Статті в журналах з теми "Mousse de biomasse"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Mousse de biomasse.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 статей у журналах для дослідження на тему "Mousse de biomasse".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Switalski, Aaron B., and Heather L. Bateman. "Anthropogenic water sources and the effects on Sonoran Desert small mammal communities." PeerJ 5 (November 10, 2017): e4003. http://dx.doi.org/10.7717/peerj.4003.
Анотація:
Anthropogenic water sources (AWS) are developed water sources used as a management tool for desert wildlife species. Studies documenting the effects of AWS are often focused on game species; whereas, the effects on non-target wildlife are less understood. We used live trapping techniques to investigate rodent abundance, biomass, and diversity metrics near AWS and paired control sites; we sampled vegetation to determine rodent-habitat associations in the Sauceda Mountains of the Sonoran Desert in Arizona. A total of 370 individual mammals representing three genera and eight species were captured in 4,800 trap nights from winter 2011 to spring 2012. A multi-response permutation procedure was used to identify differences in small mammal community abundance and biomass by season and treatment. Rodent abundance, biomass, and richness were greater at AWS compared to control sites. Patterns of abundance and biomass were driven by the desert pocket mouse (Chaetodipus penicillatus) which was the most common capture and two times more numerous at AWS compared to controls. Vegetation characteristics, explored using principal components analysis, were similar between AWS and controls. Two species that prefer vegetation structure, Bailey’s pocket mouse (C. baileyi) and white-throated woodrat (Neotoma albigula), had greater abundances and biomass near AWS and were associated with habitat having high cactus density. Although small mammals do not drink free-water, perhaps higher abundances of some species of desert rodents at AWS could be related to artificial structure associated with construction or other resources. Compared to the 30-year average of precipitation for the area, the period of our study occurred during a dry winter. During dry periods, perhaps AWS provide resources to rodents related to moisture.
2
Generali, Luigi, Carlo Bertoldi, Alessandro Bidossi, Clara Cassinelli, Marco Morra, Massimo Del Fabbro, Paolo Savadori, Nidambur Vasudev Ballal, and Luciano Giardino. "Evaluation of Cytotoxicity and Antibacterial Activity of a New Class of Silver Citrate-Based Compounds as Endodontic Irrigants." Materials 13, no. 21 (November 6, 2020): 5019. http://dx.doi.org/10.3390/ma13215019.
Анотація:
In the present study, the cytotoxicity and the antimicrobial activity of two silver citrate-based irrigant solutions were investigated. Cytotoxicity of various concentrations (0.25%, 0.5%, 1%, 2.5%, 5%) of both solutions (BioAKT and BioAKT Endo) was assessed on L-929 mouse fibroblasts using the MTT assay. For the quantitative analysis of components, an infrared (I.R.) spectroscopy was performed. The minimum inhibitory and minimal bactericidal concentrations (M.I.C. and M.B.C., respectively) were ascertained on Enterococcus faecalis strain ATCC 4083. For biofilm susceptibility after treatment with the irrigating agent, a minimum biofilm eradication concentration (M.B.E.C.) and confocal laser scanning microscope (C.L.S.M.) assays were performed. Quantification of E. faecalis cell biomass and percentage of live and dead cells in the biomass was appraised. Normality of data was analyzed using the D’Agostino & Pearson’s test and the Shapiro–Wilk test. Statistical analysis was performed using one-way analysis of variance (ANOVA) and Tukey’s test. Both silver citrate solutions showed mouse fibroblasts viability >70% when diluted to 0.25% and 0.5%. Conversely, at higher concentrations, they were extremely cytotoxic. F.T.-IR spectroscopy measurements of both liquids showed the same spectra, indicating similar chemical characteristics. No substantial contrast in antimicrobial activity was observed among the two silver citrate solutions by using broth microdilution methods, biofilm susceptibility (MBEC-HTP device), and biomass screening using confocal laser scanning microscopy (C.L.S.M.) technique. Both solutions, used as root canal irrigants, exhibited significant antimicrobial activity and low cytocompatibility at dilutions greater than 0.5%.
3
Lebaron, P., P. Bauda, N. Frank, M. C. Lett, B. Roux, J. C. Hubert, Y. Duval-Iflah, et al. "Recombinant plasmid mobilization betweenE.colistrains in seven sterile microcosms." Canadian Journal of Microbiology 43, no. 6 (June 1, 1997): 534–40. http://dx.doi.org/10.1139/m97-076.
Анотація:
Transfer by mobilization of a pBR derivative recombinant plasmid lacking transfer functions (oriT+, tra−, mob−) from one E. coli K12 strain to another was investigated in seven sterile microcosms corresponding to different environments. These microcosms were chosen as representative of environments that genetically engineered microorganisms (GEMOs) encounter after accidental release, namely attached biomass in aquatic environments (biofilm), soil, seawater, freshwater, wastewater, mouse gut, and mussel gut. GEMOs survived in the same way as the host strains in all microcosms. Recombinant DNA mobilization occurred in the mouse gut, in sterile soil, and in biofilm. The plasmid transfer rates principally reflected the environmental conditions encountered in each microcosm.Key words: recombinant DNA, plasmid transfer, mobilization, conjugation, microcosm.
4
Thouas, George A., John Sheridan, and Kerry Hourigan. "A Bioreactor Model of Mouse Tumor Progression." Journal of Biomedicine and Biotechnology 2007 (2007): 1–9. http://dx.doi.org/10.1155/2007/32754.
Анотація:
The present study represents an investigation of a novel stirred bioreactor for culture of a transformed cell line under defined hydrodynamic conditions in vitro. Cell colonies of the EL-4 mouse lymphoma cell line grown for the first time in a rotating disc bioreactor (RDB), were observed to undergo changes in phenotype in comparison to standard, static flask cultures. RDB cultures, with or without agitation, promoted the formation of adherent EL-4 cell plaques that merged to form contiguous tumor-like masses in longer-term cultures, unlike the unattached spheroid aggregates of flask cultures. Plaques grown under agitated conditions were further altered in morphology and distribution in direct response to fluid mechanical stimuli. Plaque colonies growth in RDBs with or without agitation also exhibited significant increases in production of interleukin-4 (IL-4) and lactate, suggesting an inducible “Warburg effect.” Increases in cell biomass in RDB cultures were no different to flask cultures, though a trend toward a marginal increase was observed at specific rotational speeds. The RDB may therefore be a suitable alternative method to study mechanisms of tumor progression and invasiveness in vitro, under more complex physicochemical conditions that may approximate natural tissue environments.
5
Gorbunova, A. Yu, E. P. Sannikova, I. I. Gubaidullin, O. M. Ignatova, M. Yu Kopaeva, N. V. Bulushova, and D. G. Kozlov. "Co-Purification of Recombinant Modified Glucagon-Like and Glucose-Dependent Insulinotropic Peptide to Create a Two-Component Drug for the Treatment of Type 2 Diabetes Mellitus and Obesity." Biotekhnologiya 37, no. 6 (2021): 74–83. http://dx.doi.org/10.21519/0234-2758-2021-37-6-74-83.
Анотація:
In addition to the previously developed recombinant modified human glucagon-like peptide 1 (rmglp1, Glypin), a recombinant modified human glucose-dependent insulinotropic peptide (RMGIP) has been obtained. A new universal reverse-phase HPLC technique has been proposed allowing quantitative analysis of rmGlp1 and rmGip separately and as part of a two-component preparation. The data show that the design of recombinant human rmGip according to the Glypine formula makes it possible to produce one-component and two-component preparations containing various rmGip and rmGlp1 protein ratios ranging from 1:0 to 20:1, using cell biomass samples mixed in predetermined proportions. Studies of human rmGip activity in a mouse model revealed reduced specific activity and signs of weak antagonistic effects. In this regard, there is a need for further study of human rmGip activity in a mouse model, including the use of alternative mouse or rat rmGip. type 2 diabetes mellitus; two-component drug, glucose-dependent insulinotropic peptide, glucagon-like peptide-1 The work was supported by the Internal Grant from National Research Center Kurchatov Institute.
6
Ferreiro, Elisabete, Inês R. Pita, Sandra I. Mota, Jorge Valero, Nuno R. Ferreira, Tito Fernandes, Vittorio Calabrese, Carlos A. Fontes-Ribeiro, Frederico C. Pereira, and Ana Cristina Rego. "Coriolus versicolor biomass increases dendritic arborization of newly-generated neurons in mouse hippocampal dentate gyrus." Oncotarget 9, no. 68 (August 31, 2018): 32929–42. http://dx.doi.org/10.18632/oncotarget.25978.
7
Wong, Allan HK, Donald J. McQueen, D. Dudley Williams, and Eric Demers. "Transfer of mercury from benthic invertebrates to fishes in lakes with contrasting fish community structures." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 6 (June 1, 1997): 1320–30. http://dx.doi.org/10.1139/f97-035.
Анотація:
We examined the flow of mercury (Hg) from benthic invertebrates to fishes in lakes with contrasting fish community structure. The study was carried out in two whole lakes in southcentral Ontario in 1992. Both were remote from direct sources of contamination and were chosen because of their physical and chemical similarities. Although the fish communities in the two lakes were qualitatively similar, the total number of fishes in Ranger Lake was an order of magnitude smaller than that in Mouse Lake. As a result of the lower net predation from benthivorous fishes, documented in earlier studies, Ranger Lake benthic invertebrate populations were significantly higher. However, benthic invertebrate taxa in Mouse Lake were generally larger and had higher Hg concentrations. This was partly attributed to the stunted growth of Mouse Lake fishes, which did not allow them to prey on larger benthos as a result of gape limitations. Despite the lower Hg concentrations in Ranger Lake benthos, total benthic invertebrate Hg pools were higher in this lake as a result of its higher total benthic invertebrate biomass. However, the transfer of total Hg from benthic invertebrates to fishes was higher in Mouse Lake due to the higher consumption rates of benthivorous fishes.
8
Wiscovitch-Russo, Rosana, Harinder Singh, Lauren M. Oldfield, Alexey V. Fedulov, and Norberto Gonzalez-Juarbe. "An optimized approach for processing of frozen lung and lavage samples for microbiome studies." PLOS ONE 17, no. 4 (April 5, 2022): e0265891. http://dx.doi.org/10.1371/journal.pone.0265891.
Анотація:
The respiratory tract has a resident microbiome with low biomass and limited diversity. This results in difficulties with sample preparation for sequencing due to uneven bacteria-to-host DNA ratio, especially for small tissue samples such as mouse lungs. We compared effectiveness of current procedures used for DNA extraction in microbiome studies. Bronchoalveolar lavage fluid (BALF) and lung tissue samples were collected to test different forms of sample pre-treatment and extraction methods to increase bacterial DNA yield and optimize library preparation. DNA extraction using a pre-treatment method of mechanical lysis (lung tissue) and one-step centrifugation (BALF) increased DNA yield and bacterial content of samples. In contrast, a significant increase of environmental contamination was detected after phenol chloroform isoamyl alcohol (PCI) extraction and nested PCR. While PCI has been a standard procedure used in microbiome studies, our data suggests that it is not efficient for DNA extraction of frozen low biomass samples. Finally, a DNA Enrichment kit was tested and found to improve the 16S copy number of lung tissue with a minor shift in microbial composition. Overall, we present a standardized method to provide high yielding DNA and improve sequencing coverage of low microbial biomass frozen samples with minimal contamination.
9
Memon, Tosifa A., Nam D. Nguyen, Katherine L. Burrell, Abigail F. Scott, Marysol Almestica-Roberts, Emmanuel Rapp, Cassandra E. Deering-Rice, and Christopher A. Reilly. "Wood Smoke Particles Stimulate MUC5AC Overproduction by Human Bronchial Epithelial Cells Through TRPA1 and EGFR Signaling." Toxicological Sciences 174, no. 2 (January 16, 2020): 278–90. http://dx.doi.org/10.1093/toxsci/kfaa006.
Анотація:
Abstract Mucus hypersecretion is a pathological feature of acute inflammatory and chronic obstructive pulmonary diseases. Exposure to air pollutants can be a cause of pathological mucus overproduction, but mechanisms by which different forms of air pollutants elicit this response are not fully understood. In this study, particulate matter (PM) generated from burning pine wood and other types of biomass was used to determine mechanisms by which these forms of PM stimulate mucin gene expression and secretion by primary human bronchial epithelial cells (HBECs). Biomass PM < 2.5 μm generated from pine wood and several other fuels stimulated the expression and secretion of the gel-forming glycoprotein MUC5AC by HBECs. Muc5ac gene induction was also observed in mouse airways following subacute oropharyngeal delivery of pine wood smoke PM. In HBECs, MUC5AC was also induced by the transient receptor potential ankyrin-1 (TRPA1) agonists’ coniferaldehyde, a component of pine smoke PM, and allyl isothiocyanate, and was attenuated by a TRPA1 antagonist. Additionally, inhibition of epidermal growth factor receptor (EGFR/ErbB1) and the EGFR signaling partners p38 MAPK and GSK3β also prevented MUC5AC overexpression. Collectively, our results suggest that activation of TRPA1 and EGFR, paired with alterations to p38 MAPK and GSK3β activity, plays a major role in MUC5AC overproduction by bronchial epithelial cells exposed to biomass smoke PM. These results reveal specific processes for how biomass smoke PM may impact the human respiratory system and highlight potential avenues for therapeutic manipulation of lung diseases that are affected by air pollutants.
10
Kečkéšová, Lucia, and Michal Noga. "The diet of the Common Kestrel in the urban environment of the city of Nitra." Slovak Raptor Journal 2, no. 1 (January 1, 2008): 81–85. http://dx.doi.org/10.2478/v10262-012-0021-7.
Анотація:
The diet of the Common Kestrel in the urban environment of the city of Nitra The diet of the urban Common Kestrel population was studied in Nitra during 2003-2005. Totally, 671 prey items were identified by the analysis of pellets and prey remains collected under the nesting sites. Insect, mainly represented by order Coleoptera, was found to be the most abundant prey. Regarding biomass, the Common Vole (Microtus arvalis) was predominated. In comparison with other articles published, the studied sample was rather rich in the Lesser White-toothed Shrew (Crocidura suaveolens) and the House Mouse (Mus cf. musculus).
11
Ait Kacem, Hicham, Mehdi Maanan, and Hassan Rhinane. "The value of carbon sequestration and storage in coastal habitats areas in North West of Morocco." E3S Web of Conferences 240 (2021): 01003. http://dx.doi.org/10.1051/e3sconf/202124001003.
Анотація:
Morocco, like the rest of the world, is experiencing a climate change that threatens a number of wetlands. Marine ecosystems contribute to the regulation of the Earth’s climate, but their degradation releases large quantities of greenhouse gases (GHGs) such as carbon dioxide (CO2) into the atmosphere. This paper aimed to map and model changes in carbon storage and sequestration for coastal habitats using the INVEST model, using the Sidi Moussa-Oualidia lagoon complex as a case study. To achieve this objective, several data were used, namely, land use and land cover maps between 2003 and 2020, as well as data on the amount of carbon stored in the three basins; biomass, sediment carbon (soil) and dead carbon (litter), and the annual rate of carbon accumulation in biomass and sediment. The results obtained in this work allowed us to compare the two former and current carbon stock and net sequestration scenarios and to evaluate the social cost of carbon in the study area. This study can facilitate the development of a coastal rehabilitation strategy to take advantage of the benefits of these wetlands and, at the same time, to conserve the ecosystem services provided by these environments, including the CBCS.
12
Sullivan, Thomas P., and Druscilla S. Sullivan. "Dynamics of Peripheral Populations of Great Basin Pocket Mice, Perognathus parvus, and Western Harvest Mice, Reithrodontomys megalotis, in Southern British Columbia." Canadian Field-Naturalist 122, no. 4 (October 1, 2008): 345. http://dx.doi.org/10.22621/cfn.v122i4.642.
Анотація:
The Great Basin Pocket Mouse (Perognathus parvus) and Western Harvest Mouse (Reithrodontomys megalotis) are two peripheral species occurring in the southern Okanagan Valley of British Columbia, Canada. Both species are listed as vulnerable to extirpation because of habitat loss, primarily due to conversion of natural habitat to agricultural uses and suburban expansion. Population dynamics of these two species were studied in three habitat types: old field, sagebrush, and pine forest. The Great Basin Pocket Mouse occurred at densities ranging from 12 to 28/ha in sagebrush habitats and at 2-8/ha in old fields and Ponderosa Pine forest. The Western Harvest Mouse occurred at variable densities up to 10/ha in old fields and up to 5/ha in sagebrush habitats. Mean number of lactating females for Great Basin Pocket Mice ranged from 4-8 in sagebrush, 1-5 in old fields and pine forests combined. Mean juvenile survival to adulthood ranged from 3.28 young Great Basin Pocket Mice per pregnant female in sagebrush, 4.67 in old field, and 1.82 in pine forest habitats. Mean juvenile survival to adulthood of Western Harvest Mice ranged from 1.46-1.72 young per female in old field and sagebrush habitats. Conservation of habitat features (high biomass and structural diversity of grasses and forbs) in linear habitats has the potential to maintain populations of Western Harvest Mice. The Great Basin Pocket Mouse needs features of sagebrush and old field habitats that need to be conserved as natural non-linear components in mosaics of natural and anthropogenic habitats. Both species could act as “indicators” of habitat integrity for a wide range of other vertebrate, invertebrate, and plant species in the Okanagan Valley.
13
Ley, Ruth E., J. Kirk Harris, Joshua Wilcox, John R. Spear, Scott R. Miller, Brad M. Bebout, Julia A. Maresca, Donald A. Bryant, Mitchell L. Sogin, and Norman R. Pace. "Unexpected Diversity and Complexity of the Guerrero Negro Hypersaline Microbial Mat." Applied and Environmental Microbiology 72, no. 5 (May 2006): 3685–95. http://dx.doi.org/10.1128/aem.72.5.3685-3695.2006.
Анотація:
ABSTRACT We applied nucleic acid-based molecular methods, combined with estimates of biomass (ATP), pigments, and microelectrode measurements of chemical gradients, to map microbial diversity vertically on a millimeter scale in a hypersaline microbial mat from Guerrero Negro, Baja California Sur, Mexico. To identify the constituents of the mat, small-subunit rRNA genes were amplified by PCR from community genomic DNA extracted from layers, cloned, and sequenced. Bacteria dominated the mat and displayed unexpected and unprecedented diversity. The majority (1,336) of the 1,586 bacterial 16S rRNA sequences generated were unique, representing 752 species (≥97% rRNA sequence identity) in 42 of the main bacterial phyla, including 15 novel candidate phyla. The diversity of the mat samples differentiated according to the chemical milieu defined by concentrations of O2 and H2S. Bacteria of the phylum Chloroflexi formed the majority of the biomass by percentage of bulk rRNA and of clones in rRNA gene libraries. This result contradicts the general belief that cyanobacteria dominate these communities. Although cyanobacteria constituted a large fraction of the biomass in the upper few millimeters (>80% of the total rRNA and photosynthetic pigments), Chloroflexi sequences were conspicuous throughout the mat. Filamentous Chloroflexi bacteria were identified by fluorescence in situ hybridization within the polysaccharide sheaths of the prominent cyanobacterium Microcoleus chthonoplastes, in addition to free living in the mat. The biological complexity of the mat far exceeds that observed in other polysaccharide-rich microbial ecosystems, such as the human and mouse distal guts, and suggests that positive feedbacks exist between chemical complexity and biological diversity.
14
Brown, Peter R., Micah J. Davies, Grant R. Singleton, and J. David Croft. "Can farm-management practices reduce the impact of house mouse populations on crops in an irrigated farming system?" Wildlife Research 31, no. 6 (2004): 597. http://dx.doi.org/10.1071/wr03063.
Анотація:
The impacts of a range of farm-management practices on house mouse (Mus domesticus) populations were tested in a large replicated field study in a complex irrigated farming system in southern New South Wales, Australia. An advisory panel, made up of farmers, extension officers, industry representatives and scientists developed a series of best-practice farm-management actions to minimise the impact of mice. Twelve experimental sites were split into six treated sites, where farmers were encouraged to conduct the recommended practices, and six untreated sites, where farmers conducted their normal farming practices. Mouse abundance was generally low to moderate for the 4-year project (5–60% adjusted trap success). We found significant reductions in population abundance of mice on treated sites when densities were moderate, but no differences when densities were low. Biomass of weeds and grasses around the perimeter of crops were significantly lower on treated sites because of applications of herbicide sprays and grazing by sheep. We could not detect any significant difference in mouse damage to crops between treated and untreated sites; however, levels of damage were low (<5%). Yields of winter cereals and rice crops were significantly higher on treated sites by up to 40%. An analysis of benefits and costs of conducting farming practices on treated sites compared with untreated sites showed a 2 : 1 benefit to cost ratio for winter cereals, 9 : 1 for rice and 4 : 1 for soybeans.
15
Damon, Andrea L., Lesley E. Scudder, Dmitri V. Gnatenko, Varsha Sitaraman, Patrick Hearing, Jolyon Jesty, and Wadie F. Bahou. "Altered bioavailability of platelet-derived factor VIII during thrombocytosis reverses phenotypic efficacy in haemophilic mice." Thrombosis and Haemostasis 100, no. 12 (2008): 1111–22. http://dx.doi.org/10.1160/th08-04-0242.
Анотація:
SummaryEctopic delivery of factor VIII (FVIII) to megakaryocytes (Mk) represents a viable approach for localized tenase generation by concentrating the FVIIIa/FIXa enzymecofactor complex onto activated platelet membranes. We utilized a core rat platelet factor 4 (PF4) promoter for Mk/platelet-restricted expression of human B-domain-deleted (hBDD) FVIII within the background of a haemophilia A mouse (rPF4/hBDD/FVIII-/-). Platelets from rPF4/hBDD/FVIII-/- mice contained ∼122 mU FVIII:C/1x109 platelets/ml with no detectable plasmatic FVIII:C,and with no effect on α-granule-derived platelet factorV/Va function.Paired tenase assays (± thrombin) confirmed that platelet (pt) FVIII (unlike platelet FV) required thrombin cleavage for complete activation. rPF4/hBDD/FVIII-/- mice exposed to a thrombocytotic stimulus (thrombopoietin, TPO) demonstrated a statistically-significant 66% reduction in molar ptFVIII activity with a non-significant reduction in total ptFVIII biomass. Decreased molar ptFVIII concentration correlated with loss of phenotypic correction as evaluated using a haemostatic tail-snip assay. Comparative studies using a transgenic mouse expressing human amyloid-β-precursor protein (hAβPP) from the rPF4 promoter confirmed diminished hAβPP expression without affecting endogenous α-granule PF4, establishing generalizability of these observations.While Mk/plateletreleased ptFVIII (unlike pFV) is proteolytically inactive, we also conclude that thrombocytotic stimuli negatively affect ptFVIII bioavailability and phenotypic efficacy, results which correlate best with molar ptFVIII concentration, and not systemically available ptFVIII.
16
McConkey, Kim R., and David J. Chivers. "Low mammal and hornbill abundance in the forests of Barito Ulu, Central Kalimantan, Indonesia." Oryx 38, no. 4 (October 2004): 439–47. http://dx.doi.org/10.1017/s0030605304000821.
Анотація:
Faunal surveys in Kalimantan have been biased towards primates in protected forests close to the coast. Relatively little has been documented on other animal species, particularly in the vast interior forests. The results of a 1996–97 census of nine large mammal and eight hornbill species in tropical lowland forest in Barito Ulu, Central Kalimantan are reported here. Pigs Sus barbatus had the highest biomass, but this was due to large numbers migrating through the study area over 4 months and the resident population is probably low. Langurs Presbytis rubicunda and hybrid gibbons Hylobates mulleri × agilis had the highest biomass of all resident species. Orang-utans Pongo pygmaeus were absent from the area during the study period and pig-tailed macaques Macaca nemestrina were rarely seen. The resident hornbill species (Anthracoceros malayanus, Anorrhinus galeritus, Buceros vigil and B. rhinoceros) had high densities compared to that reported from lowland areas, but overall hornbill density was low due to the absence of the nomadic Aceros corrugatus and A. undulatus, except during peak fruit abundance. Sun bears Helarctos malayanus, long-tailed macaques M. fascicularis, muntjacs Muntiacus spp. and mouse deer Tragulus spp. were at low densities. Density of two large squirrel species, Ratufa affinis and Sundasciurus hippiurus, was lower than has been reported in Sarawak, but the density of Prevost's squirrel Callosciurus prevostii was higher. We discuss hunting pressure, isolation, low abundance of large fruit trees, poor soils, and specific habitat preferences as possible explanations for the low mammal and hornbill density at Barito Ulu.
17
Milani, Chiara, Francesca Farina, Laura Botto, Luca Massimino, Elena Lonati, Elisabetta Donzelli, Elisa Ballarini, et al. "Systemic Exposure to Air Pollution Induces Oxidative Stress and Inflammation in Mouse Brain, Contributing to Neurodegeneration Onset." International Journal of Molecular Sciences 21, no. 10 (May 24, 2020): 3699. http://dx.doi.org/10.3390/ijms21103699.
Анотація:
In northern Italy, biomass burning-derived (BB) particles and diesel exhaust particles (DEP) are considered the most significant contributors to ultrafine particle (UFP) emission. However, a comparison between their impact on different brain regions was not investigated until now. Therefore, male BALB/c mice were treated with a single or three consecutive intratracheal instillations using 50 µg of UFPs in 100 µL of isotonic saline solution or 100 µL of isotonic saline solution alone, and brains were collected and analyzed. Proteins related to oxidative stress and inflammation, as well as Alzheimer’s disease markers, were examined in the hippocampus, cerebellum, and the rest of the brain (RoB). Histopathological examination of the brain was also performed. Moreover, correlations among different brain, pulmonary, and cardiovascular markers were performed, allowing us to identify the potentially most stressful UFP source. Although both acute exposures induced inflammatory pathways in mouse brain, only DEP showed strong oxidative stress. The sub-acute exposure also induced the modulation of APP and BACE1 protein levels for both UFPs. We observed that DEP exposure is more harmful than BB, and this different response could be explained by this UFP’s different chemical composition and reactivity.
18
Lowrie, F. M., J. M. Behnke, and C. J. Barnard. "Density-dependent effects on the survival and growth of the rodent stomach wormProtospirura muricolain laboratory mice." Journal of Helminthology 78, no. 2 (June 2004): 121–28. http://dx.doi.org/10.1079/joh2003230.
Анотація:
AbstractThe spirurid nematode,Protospirura muricola, is of intrinsic interest as a rodent model of gastric nematode infections. Since worm burdens can be very heavy in nature, density dependent processes may constrain parasite growth. Laboratory mice (BKW) were exposed to varying doses of infective larvae ofP. muricolain the range 5 to 40 third-stage larvae (L3), in four separate experiments in which progressively higher doses were utilized. All mice were culled 60 days after infection and a total of 518 worms (226 male and 292 female worms) was recovered, measured and weighed. Overall survival was 58.9%, but survival declined significantly with increasing dose by approximately 21% (from 66% at 5 L3 per mouse to 52% at 40 L3 per mouse). The length and weight of worms correlated positively in both sexes. Total worm biomass increased linearly with increasing numbers of worms. However, whilst the length and weight of male worms declined with increasing worm burden (8.4 and 24.6% respectively), female worms were less affected, only length showing a significant reduction with increasing parasite burden (16.0%). Therefore, increasing worm burdens impeded growth ofP. muricola, but reduction in length and weight were relatively small in relation to the overall size of this nematode. Increasing worm burdens were associated with loss of host weight and reduction in stomach weight and worm burdens in excess of 20 exerted a measurable cost to the host, which in the field, may be associated with loss of overall host fitness.
19
Trung, Nguyen Thi, and Truong Nam Hai. "Study on using the hybrid cell a6g11c9 to produce the anti-a monoclonal antibody that agglunating a antigen on the surface of red blood cells." TAP CHI SINH HOC 40, no. 1 (December 6, 2017): 25–31. http://dx.doi.org/10.15625/0866-7160/v40n1.9154.
Анотація:
Almost of the ABO blood grouping reagents is being trading derive from the monoclonal antibodies. There are two methods to produce the monoclonal antibodies from hybridoma lines, which were in vitro method (hybridoma cultured in the medium) and in vivo method (hybridoma cultured in the mice intra-abdominal). In Vietnam, Nguyen Thi Trung and co-authors was succesfully screened in hybridoma cell line A6G11C9 which generating of the anti A monoclonal antibody agglutinated A antigen on the surface of red blood cells. The fusion of mouse lymohocyte B generated anti-A antibody with mouse myeloma sp2/0 is formed that hybrid cell lines. The anti-A monoclonal antibody is produced from hybridoma cell line A6G11C9 have been highly intensive confirmed. It is capability of growth and anti B monoclonal antibody producing stability through the generations. In this study, the process to produce large amounts of monoclonal antibodies from B4D10C9 hybridoma by in vitro method are published. Firstly, hybridoma cells are stored in liquid nitrogen to wake by culture in medium. Then, First, hybrid cells are stored frozen in liquid nitrogen to wake cultured cells. Then, they were first inoculated to produce enough biomass to serve a larger scale. Cell biomass continues to be second inoculated into DMEM containing 10% fetal bovin serum for 10 days. The culture medium contained anti-A monoclonal antibodies were collected by centrifugation to remove cells. The anti-A monoclonal antibody levels in culture medium was concentrated and remove phenol red indicator by the precipitation with NH4SO4 50% saturated. The anti-A monoclonal antibody solution at 5 times concentrated have been better agglutinated with erythrocytes containing A antigen than monoclonal antibody solution non-concentration. 150 ml of concentrated antibodies were produced. Antibody titer of the anti-A monoclonal antibodies in the concentrated 5 times solution was 1/512. The intensity of the reaction anti-A monclonal antibody with red blood cell containing A antigen was 4+. Citation: Nguyen Thi Trung, Truong Nam Hai, 2018. Study on using the hybrid cell a6g11c9 to produce the anti-a monoclonal antibody that agglunating a antigen on the surface of red blood cells. Tap chi Sinh hoc, 40(1): x-xx. DOI: 10.15625/0866-7160/v40n1.9154. *Corresponding author: tnhai@ibt.ac.vn Received 12 January 2017, accepted 20 December 2017
20
Watt, Matthew J., Ashlee K. Clark, Luke A. Selth, Vanessa R. Haynes, Natalie Lister, Richard Rebello, Laura H. Porter, et al. "Suppressing fatty acid uptake has therapeutic effects in preclinical models of prostate cancer." Science Translational Medicine 11, no. 478 (February 6, 2019): eaau5758. http://dx.doi.org/10.1126/scitranslmed.aau5758.
Анотація:
Metabolism alterations are hallmarks of cancer, but the involvement of lipid metabolism in disease progression is unclear. We investigated the role of lipid metabolism in prostate cancer using tissue from patients with prostate cancer and patient-derived xenograft mouse models. We showed that fatty acid uptake was increased in human prostate cancer and that these fatty acids were directed toward biomass production. These changes were mediated, at least partly, by the fatty acid transporter CD36, which was associated with aggressive disease. Deleting Cd36 in the prostate of cancer-susceptible Pten−/− mice reduced fatty acid uptake and the abundance of oncogenic signaling lipids and slowed cancer progression. Moreover, CD36 antibody therapy reduced cancer severity in patient-derived xenografts. We further demonstrated cross-talk between fatty acid uptake and de novo lipogenesis and found that dual targeting of these pathways more potently inhibited proliferation of human cancer-derived organoids compared to the single treatments. These findings identify a critical role for CD36-mediated fatty acid uptake in prostate cancer and suggest that targeting fatty acid uptake might be an effective strategy for treating prostate cancer.
21
Happo, Mikko S., Oskari Uski, Pasi I. Jalava, Joachim Kelz, Thomas Brunner, Pasi Hakulinen, Jorma Mäki-Paakkanen, et al. "Pulmonary inflammation and tissue damage in the mouse lung after exposure to PM samples from biomass heating appliances of old and modern technologies." Science of The Total Environment 443 (January 2013): 256–66. http://dx.doi.org/10.1016/j.scitotenv.2012.11.004.
22
Catauro, Michelina, Giovanni Dal Poggetto, Severina Pacifico, Fernanda Andreola, Isabella Lancellotti, and Luisa Barbieri. "A New System of Sustainable Silico-Aluminous and Silicate Materials for Cultivation Purpose within Sustainable Buildings: Chemical-Physical, Antibacterial and Cytotoxicity Properties." Applied Sciences 12, no. 1 (January 3, 2022): 434. http://dx.doi.org/10.3390/app12010434.
Анотація:
In this study, we compared the chemical-physical, antibacterial, and cytotoxicity properties of silico-aluminous and silicate materials for outdoor (green roof, planted walls) and indoor (urban farms, indoor microgreen gardens) cultivation purpose in a context of sustainable construction. Glasses and lightweight aggregates were tailored starting from waste, by-product, and post-consumer and bioproducts (packaging glass cullet, cattle bone flour ash, vegetable biomass ash, spent coffee ground, degreased from biomass of prepupae of Black Soldier Flies) mixed together with a national ferruginous red clay, quarry scrap pumice and, if necessary, with K2CO3 of reagent grade. The first type of material was obtained by melting at 1200 °C and the second one by powder sintering at 1000 °C. All specimens, subjected to antibacterial test, showed both low zone of inhibitions towards two Gram-negative and two Gram-positive bacterial strains. A cytotoxicity test on mouse embryonic fibroblast NIH-3T3 cell line directly exposed to the investigated materials was performed at three different exposure times (1 h, 3 h, and 6 h). Data acquired highlighted that the materials positively affected redox mitochondrial activity of the fibroblast cells. The concentrations of leachate heavy metals detected on selected materials in water at room temperature after 24 h were lower than the European law limit and an interesting release of P, K, and N nutrients was noted for those formulations designed for agronomic purposes. pH, falling on average within the 6.5–7.5 range, is optimal for most crops, and the specific conductivity <2 dS/m indicates no depression danger for crops. Both bulk density <1200 kg/m3 and porosity over 50% seem to ensure good performance of lightening, drainage, water reservation, and oxygenation of the roots.
23
Mohanty, Soumitra, Prajna Jena, Ranjit Mehta, Rashmirekha Pati, Birendranath Banerjee, Satish Patil, and Avinash Sonawane. "Cationic Antimicrobial Peptides and Biogenic Silver Nanoparticles Kill Mycobacteria without Eliciting DNA Damage and Cytotoxicity in Mouse Macrophages." Antimicrobial Agents and Chemotherapy 57, no. 8 (May 20, 2013): 3688–98. http://dx.doi.org/10.1128/aac.02475-12.
Анотація:
ABSTRACTWith the emergence of multidrug-resistant mycobacterial strains, better therapeutic strategies are required for the successful treatment of the infection. Although antimicrobial peptides (AMPs) and silver nanoparticles (AgNPs) are becoming one of the popular antibacterial agents, their antimycobacterial potential is not fully evaluated. In this study, we synthesized biogenic-silver nanoparticles using bacterial, fungal, and plant biomasses and analyzed their antibacterial activities in combination with AMPs against mycobacteria.Mycobacterium smegmatiswas found to be more susceptible to AgNPs compared toM. marinum. We found that NK-2 showed enhanced killing effect with NP-1 and NP-2 biogenic nanoparticles at a 0.5-ppm concentration, whereas LLKKK-18 showed antibacterial activity only with NP-2 at 0.5-ppm dose againstM. smegmatis. In case ofM. marinumNK-2 did not show any additive activity with NP-1 and NP-2 and LLKKK-18 alone completely inhibited the bacterial growth. Both NP-1 and NP-2 also showed increased killing ofM. smegmatisin combination with the antituberculosis drug rifampin. The sizes and shapes of the AgNPs were determined by transmission electron microscopy and dynamic light scattering. AgNPs showed no cytotoxic or DNA damage effects on macrophages at the mycobactericidal dose, whereas treatment with higher doses of AgNPs caused toxicity and micronuclei formation in cytokinesis blocked cells. Macrophages actively endocytosed fluorescein isothiocyanate-labeled AgNPs resulting in nitric oxide independent intracellular killing ofM. smegmatis. Apoptosis and cell cycle studies showed that treatment with higher dose of AgNPs arrested macrophages at the G1-phase. In summary, our data suggest the combined effect of biogenic-AgNPs and antimicrobial peptides as a promising antimycobacterial template.
24
Janus, Łukasz, Julia Radwan-Pragłowska, Marek Piątkowski, and Dariusz Bogdał. "Coumarin-Modified CQDs for Biomedical Applications—Two-Step Synthesis and Characterization." International Journal of Molecular Sciences 21, no. 21 (October 29, 2020): 8073. http://dx.doi.org/10.3390/ijms21218073.
Анотація:
Waste biomass such as lignin constitutes a great raw material for eco-friendly carbon quantum dots (CQDs) synthesis, which find numerous applications in various fields of industry and medicine. Carbon nanodots, due to their unique luminescent properties as well as water-solubility and biocompatibility, are superior to traditional organic dyes. Thus, obtainment of CQDs with advanced properties can contribute to modern diagnosis and cell visualization method development. In this article, a new type of coumarin-modified CQD was obtained via a hybrid, two-step pathway consisting of hydrothermal carbonization and microwave-assisted surface modification with coumarin-3-carboxylic acid and 7-(Diethylamino) coumarin-3-carboxylate. The ready products were characterized over their chemical structure and morphology. The nanomaterials were confirmed to have superior fluorescence characteristics and quantum yield up to 18.40%. They also possessed the ability of biomolecules and ion detection due to the fluorescence quenching phenomena. Their lack of cytotoxicity to L929 mouse fibroblasts was confirmed by XTT assay. Moreover, the CQDs were proven over their applicability in real-time bioimaging. Obtained results clearly demonstrated that proposed surface-modified carbon quantum dots may become a powerful tool applicable in nanomedicine and pharmacy.
25
Ito, Akira, and Tsuneo Kamiyama. "Cortisone-sensitive, innate resistance to Hymenolepis nana infection in congenitally athymic nude rats." Journal of Helminthology 61, no. 2 (June 1987): 124–28. http://dx.doi.org/10.1017/s0022149x0000986x.
Анотація:
ABSTRACTThe innate resistance of the unnatural rat host to the mouse tapeworm Hymenolepis nana is cortisone sensitive but thymus independent. When congenitally athymic nude rats were orally given eggs, cysticercoids, or adult worms of H. nana, no lumenal adults were established except when they were treated with cortisone acetate during the expected lumenal development. The effect of cortisone to promote adult maturation in the rats was compared in nude and normal rats given eggs of H. nana. The fecundity of the worm (assessed by the fresh worm biomass and the number of infective eggs produced) was much higher in cortisone-treated nude rats than in cotrisone-trated norml rats. When the nude rats recostituted with thymocytes were given eggs and treated with cortisone, the fecundity of H. nana dropped to the same level as in cortisone-treated normal rats. It is strongly suggested that the unnatural rat host has thymus-independent cortisone sensitive resistance to an intial infection (which is the main component of the innate resistance and blocks the lumenal establishment of this parasite) and thymus-dependent resistance (which suppresses the established worm' fecudity and may be ascribed to acquired resistance to the ongoing infection).
26
Ramírez-Hernández, Gustavo, and L. Gerardo Herrera M. "Nutritional importance of seeds and arthropods to painted spiny pocket mice (Lyomis pictus): the effects of season and forest degradation." Canadian Journal of Zoology 88, no. 12 (December 2010): 1226–34. http://dx.doi.org/10.1139/z10-087.
Анотація:
Temporal and spatial fluctuations in food abundance may affect the feeding habits of vertebrates in tropical dry forests. We explored the effects of season and forest degradation in dietary patterns of the painted spiny pocket mouse ( Lyomis pictus (Thomas, 1893)) (Heteromyidae) in a Mexican tropical dry forest. We used carbon (13C, 12C) and nitrogen (15N, 14N) stable isotope analyses to test the hypotheses that (i) L. pictus would increase its use of arthropods during the rainy season when seeds are less available on the forest floor and (ii) that L. pictus would increase its use of arthropods in degraded forest compared with conserved forest. Our hypotheses were wrong because assimilated biomass was derived almost exclusively from seeds in both seasons and the importance of arthropods was marginal in both sites. Examination of food remains in feces and cheek pouches confirmed these trophic patterns. Seed hoarding during the season of high seed availability probably allows L. pictus to subsist on a seed-based diet throughout the year in conserved and disturbed forests. This behavioral trait would enable L. pictus to maintain its specialized feeding habit in environments threatened by habitat degradation.
27
Wu, Liu, Sun, Lin, Zhan, and Fu. "Preparation of Selenium-Enriched Yeast by Re-Using Discarded Saccharomyces cerevisiae from the Beer Industry for Se-Supplemented Fodder Applications." Applied Sciences 9, no. 18 (September 9, 2019): 3777. http://dx.doi.org/10.3390/app9183777.
Анотація:
Both inorganic and organic selenium (Se) can prevent and treat various diseases caused by Se deficiency. However, organic Se has less toxicity and a higher absorption rate than inorganic Se. In this study, inorganic Se (Na2SeO3) was bio-transformed into Se-enriched discarded beer yeast (Se-enriched DB-yeast) through fermentation accumulation by re-using discarded Saccharomyces cerevisiae from the beer industry for Se-enriched fodder application. Through a single-factor experiment and L9(34)-orthogonal test for optimization of fermentation conditions, the Se content and biomass of Se-enriched DB-yeast were calculated as 14.95 mg/L and 7.3 g/L, respectively, under the optimized condition. The total amino-acid content of Se-enriched DB-yeast was increased by 9.9% compared with that from DB yeast. Additionally, alkaline amino-acid content was increased, whereas acidic amino-acid and sulfur-containing amino-acid contents were decreased. Reducing capacity, hydroxyl radical removal capacity, and sulfhydryl content after treatment with H2O2 of the Se-enriched DB-yeast extracted protein were obviously increased compared with those of the DB-yeast extracted protein. Mouse and genetically improved farmed tilapia (Oreochromis niloticus) (GIFT) bioassays showed that the Se sedimentation of organs and serum indexes after feeding Se-enriched DB-yeast-containing fodder were higher than those of DB-yeast-containing fodder. The half lethal dose (LD50) of Se-enriched DB-yeast (9260.0 mg/kg body weight (BW), 18.97 mg/kg of Se content, non-toxic level) was considerably higher than that of Na2SeO3 (20.0 mg/kg BW, 5.08 mg/kg of Se content, highly toxic level) against mouse. Therefore, Se-enriched yeast prepared by re-using discarded S. cerevisiae from beer industry fermentation accumulation has the potential to be a safe and effective Se-enriched fodder additive.
28
Casas-Arrojo, Virginia, Juan Decara, María de los Ángeles Arrojo-Agudo, Claudia Pérez-Manríquez, and Roberto T. Abdala-Díaz. "Immunomodulatory, Antioxidant Activity and Cytotoxic Effect of Sulfated Polysaccharides from Porphyridium cruentum. (S.F.Gray) Nägeli." Biomolecules 11, no. 4 (March 24, 2021): 488. http://dx.doi.org/10.3390/biom11040488.
Анотація:
Porphyridium cruentum is a unicellular microalga that can synthesize and secrete to the culture medium-high amounts of polysaccharides. In this study, the immunomodulatory, cytotoxic effect and antioxidant activity of the sulfated polysaccharides (PcSPs) were determinate. The PcSPs were precipitated with 2% Cetylpyridinium bromide hydrate and ethanol and purified by dialysis. The extract was lyophilized for its characterization by Fourier transform-Infrared (FT-IR) spectroscopy and gas chromatography–mass spectrometry (GC-MS). The antioxidant activity of PcSPs were examined with assay 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and compared with that of the biomass, observing significant differences between the results obtained from the PcSPs and biomass. To determine their ability to induce cytokine production Tumor Necrosis Factor alpha (TNF-α) and interleukina-6 (IL-6), the immunomodulatory activity of the PcSPs has been evaluated. In the mouse macrophage cell line (RAW 264.7), PcSPs are potent inducers of IL-6 cytokines but mainly of TNF-α. The cytotoxic capacity of PcSPs was measured by the MTT colorimetric assay in colorectal carcinoma (HTC-116), human leukemia (U-937 and HL-60), breast cancer (MCF-7), lung cancer (NCI-H460) and human gingival fibroblasts (HGF-1) cell lines. The IC50 value of 2311.20 µg mL−1, 1676.74 µg mL−1, 1089.63 µg mL−1, 5498.14 µg mL−1 and 2861.49 µg mL−1 respectively in the tumor lines and 5022.55 µg mL−1 in gingival fibroblasts were obtained. Our study suggested that PcSPs from P. cruentum have a moderate immunomodulatory and cytotoxic effect. The results obtained indicate that the polysaccharides from P. cruentum are potent inducers of IL-6 cytokines and, most importantly, of TNF-α. PcSPs showed no evidence of antigenic activity or hypersensitivity when administered intraperitoneally in mice. Furthermore, the in vivo study revealed an improvement of local inflammatory response against stress in the peritoneum. These findings suggest that the PcSPs from P. cruentum might have potential as a valuable ingredient in nutraceutical products.
29
Kang, Sini, Rui Li, Hui Jin, Hyun Ju You, and Geun Eog Ji. "Effects of Selenium- and Zinc-Enriched Lactobacillus plantarum SeZi on Antioxidant Capacities and Gut Microbiome in an ICR Mouse Model." Antioxidants 9, no. 10 (October 21, 2020): 1028. http://dx.doi.org/10.3390/antiox9101028.
Анотація:
Selenium and zinc are essential trace minerals for humans with various biological functions. In this study, selenium- and zinc-tolerant lactic acid bacteria (LAB) isolates were screened out from human fecal samples. Amongst three hundred LAB isolates, the Lactobacillus plantarum SeZi strain displayed the tolerance against selenium and zinc with the greatest biomass production and bioaccumulation of selenium and zinc. To further assess the characteristics of this strain, the lyophilized L. plantarum SeZi were prepared and administered to Institute of Cancer Research (ICR) mice. The mice were divided into four groups, provided with normal chow (Con), or normal chow supplemented with Na2SeO3 and ZnSO4∙7H2O (SZ), L. plantarum SeZi (Lp), or selenium- and zinc-enriched L. plantarum SeZi (SZ + Lp), respectively. After 4 weeks of oral administration, the concentrations of selenium and zinc in blood were significantly increased in the SZ + Lp group when compared to the control or SZ group (p < 0.05). The increased selenium level led to an enhanced glutathione peroxidase activity and decreased blood malondialdehyde level in the SZ + Lp group (p < 0.05). Meanwhile, the results of bacterial community and microbial metabolic pathway analysis via 16S rRNA gene amplicon sequencing showed that L. plantarum SeZi significantly promoted the utilization of selenocysteine, seleno-cystathionine and seleno-methionine in the selenocompounds metabolism. Here, the in vivo antioxidant capacities of the selenium- and zinc-enriched lactobacillus strain showed us the utilization of a unique probiotic as a Se/Zn supplement with high availability, low toxicity, and additional probiotic advantages.
30
Huang, Chun-Yin, Yu-Ting Weng, Po-Chen Li, Nien-Tsu Hsieh, Chun-I. Li, Hsiao-Sheng Liu, and Ming-Fen Lee. "Calcitriol Suppresses Warburg Effect and Cell Growth in Human Colorectal Cancer Cells." Life 11, no. 9 (September 14, 2021): 963. http://dx.doi.org/10.3390/life11090963.
Анотація:
Increasing lines of evidence indicate that the biologically active form of vitamin D, calcitriol (1,25-dihydroxyvitamin D3), prevents cancer progression by reducing cell proliferation, increasing cell differentiation, and inhibiting angiogenesis, among other potential roles. Cancer cells in solid tumors preferably undergo the “Warburg effect” to support cell growth by upregulating glycolysis, and the glycolytic intermediates further serve as building blocks to generate biomass. The objective of the current study is to investigate whether calcitriol affects glucose metabolism and cell growth in human colorectal cancer cells. Calcitriol reduced the expression of cyclin D1 and c-Myc. In addition, calcitriol reduced the expression of glucose transporter 1 (GLUT1) and key glycolytic enzymes and decreased extracellular acidification rate but increased oxygen consumption rate in human colorectal cancer cells. In a subcutaneous HT29 xenograft NOD/SCID mouse model, the volume and weight of the tumors were smaller in the calcitriol groups as compared with the control group, and the expression levels of GLUT1 and glycolytic enzymes, hexokinase 2 and lactate dehydrogenase A, were also lower in the calcitriol groups in a dose-responsive manner. Our data indicate that calcitriol suppresses glycolysis and cell growth in human colorectal cancer cells, suggesting an inhibitory role of the biologically active form of vitamin D in colorectal cancer progression.
31
Gallo, Nunzia, Maria Lucia Natali, Alessandra Quarta, Antonio Gaballo, Alberta Terzi, Teresa Sibillano, Cinzia Giannini, et al. "Aquaponics-Derived Tilapia Skin Collagen for Biomaterials Development." Polymers 14, no. 9 (May 2, 2022): 1865. http://dx.doi.org/10.3390/polym14091865.
Анотація:
Collagen is one of the most widely used biomaterials in health-related sectors. The industrial production of collagen mostly relies on its extraction from mammals, but several issues limited its use. In the last two decades, marine organisms attracted interest as safe, abundant, and alternative source for collagen extraction. In particular, the possibility to valorize the huge quantity of fish industry waste and byproducts as collagen source reinforced perception of fish collagen as eco-friendlier and particularly attractive in terms of profitability and cost-effectiveness. Especially fish byproducts from eco-sustainable aquaponics production allow for fish biomass with additional added value and controlled properties over time. Among fish species, Oreochromis niloticus is one of the most widely bred fish in large-scale aquaculture and aquaponics systems. In this work, type I collagen was extracted from aquaponics-raised Tilapia skin and characterized from a chemical, physical, mechanical, and biological point of view in comparison with a commercially available analog. Performed analysis confirmed that the proprietary process optimized for type I collagen extraction allowed to isolate pure native collagen and to preserve its native conformational structure. Preliminary cellular studies performed with mouse fibroblasts indicated its optimal biocompatibility. All data confirmed the eligibility of the extracted Tilapia-derived native type I collagen as a biomaterial for healthcare applications.
32
Liu, Boyi, Yan Tai, Satyanarayana Achanta, Melanie M. Kaelberer, Ana I. Caceres, Xiaomei Shao, Jianqiao Fang, and Sven-Eric Jordt. "IL-33/ST2 signaling excites sensory neurons and mediates itch response in a mouse model of poison ivy contact allergy." Proceedings of the National Academy of Sciences 113, no. 47 (November 7, 2016): E7572—E7579. http://dx.doi.org/10.1073/pnas.1606608113.
Анотація:
Poison ivy-induced allergic contact dermatitis (ACD) is the most common environmental allergic condition in the United States. Case numbers of poison ivy ACD are increasing due to growing biomass and geographical expansion of poison ivy and increasing content of the allergen, urushiol, likely attributable to rising atmospheric CO2. Severe and treatment-resistant itch is the major complaint of affected patients. However, because of limited clinical data and poorly characterized models, the pruritic mechanisms in poison ivy ACD remain unknown. Here, we aim to identify the mechanisms of itch in a mouse model of poison ivy ACD by transcriptomics, neuronal imaging, and behavioral analysis. Using transcriptome microarray analysis, we identified IL-33 as a key cytokine up-regulated in the inflamed skin of urushiol-challenged mice. We further found that the IL-33 receptor, ST2, is expressed in small to medium-sized dorsal root ganglion (DRG) neurons, including neurons that innervate the skin. IL-33 induces Ca2+ influx into a subset of DRG neurons through neuronal ST2. Neutralizing antibodies against IL-33 or ST2 reduced scratching behavior and skin inflammation in urushiol-challenged mice. Injection of IL-33 into urushiol-challenged skin rapidly exacerbated itch-related scratching via ST2, in a histamine-independent manner. Targeted silencing of neuronal ST2 expression by intrathecal ST2 siRNA delivery significantly attenuated pruritic responses caused by urushiol-induced ACD. These results indicate that IL-33/ST2 signaling is functionally present in primary sensory neurons and contributes to pruritus in poison ivy ACD. Blocking IL-33/ST2 signaling may represent a therapeutic approach to ameliorate itch and skin inflammation related to poison ivy ACD.
33
Berry, David, Esther Mader, Tae Kwon Lee, Dagmar Woebken, Yun Wang, Di Zhu, Marton Palatinszky, et al. "Tracking heavy water (D2O) incorporation for identifying and sorting active microbial cells." Proceedings of the National Academy of Sciences 112, no. 2 (December 30, 2014): E194—E203. http://dx.doi.org/10.1073/pnas.1420406112.
Анотація:
Microbial communities are essential to the function of virtually all ecosystems and eukaryotes, including humans. However, it is still a major challenge to identify microbial cells active under natural conditions in complex systems. In this study, we developed a new method to identify and sort active microbes on the single-cell level in complex samples using stable isotope probing with heavy water (D2O) combined with Raman microspectroscopy. Incorporation of D2O-derived D into the biomass of autotrophic and heterotrophic bacteria and archaea could be unambiguously detected via C-D signature peaks in single-cell Raman spectra, and the obtained labeling pattern was confirmed by nanoscale-resolution secondary ion MS. In fast-growingEscherichia colicells, label detection was already possible after 20 min. For functional analyses of microbial communities, the detection of D incorporation from D2O in individual microbial cells via Raman microspectroscopy can be directly combined with FISH for the identification of active microbes. Applying this approach to mouse cecal microbiota revealed that the host-compound foragersAkkermansia muciniphilaandBacteroides acidifaciensexhibited distinctive response patterns to amendments of mucin and sugars. By Raman-based cell sorting of active (deuterated) cells with optical tweezers and subsequent multiple displacement amplification and DNA sequencing, novel cecal microbes stimulated by mucin and/or glucosamine were identified, demonstrating the potential of the nondestructive D2O-Raman approach for targeted sorting of microbial cells with defined functional properties for single-cell genomics.
34
Ma, Zhou, Chen, Urriola, Shurson, Ruan, and Chen. "Metabolomic Evaluation of Scenedesmus sp. as a Feed Ingredient Revealed Dose-Dependent Effects on Redox Balance, Intermediary and Microbial Metabolism in a Mouse Model." Nutrients 11, no. 9 (August 21, 2019): 1971. http://dx.doi.org/10.3390/nu11091971.
Анотація:
Scenedesmus is a common green algae genus with high biomass productivity, and has been widely used in biofuel production and waste water management. However, the suitability and metabolic consequences of using Scenedesmus as an animal feed ingredient have not been examined in detail. In this study, the influences of consuming Scenedesmus on the metabolic status of young mice were investigated through growth performance, blood chemistry, and liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. Compared to the control diet, feeding a diet containing 5% Scenedesmus improved growth performance while the diet containing 20% Scenedesmus suppressed it. Among common macronutrients-derived blood biochemicals, serum triacylglycerols and cholesterol levels were dramatically decreased by feeding the 20% Scenedesmus diet. Metabolomic analysis of liver, serum, feces, and urine samples indicated that Scenedesmus feeding greatly affected the metabolites associated with amino acid, lipid, purine, microbial metabolism, and the endogenous antioxidant system. The growth promotion effect of feeding the 5% Scenedesmus diet was associated with elevated concentrations of antioxidants, an expanded purine nucleotide cycle, and modified microbial metabolism, while the growth suppression effect of feeding the 20% Scenedesmus diet was correlated to oxidative stress, disrupted urea cycle, upregulated fatty acid oxidation, and an imbalanced lipidome. These correlations among Scenedesmus dietary inclusion rate, individual metabolite markers, and growth performance suggest the need to define the dietary inclusion rate threshold for using Scenedesmus and other microalgae supplements as feed ingredients, and also warrant further mechanistic investigations on the biological processes connecting specific constituents of Scenedesmus with the metabolic effects observed in this study.
35
Newsome, Seth D., Kelli L. Feeser, Christina J. Bradley, Caitlin Wolf, Cristina Takacs-Vesbach, and Marilyn L. Fogel. "Isotopic and genetic methods reveal the role of the gut microbiome in mammalian host essential amino acid metabolism." Proceedings of the Royal Society B: Biological Sciences 287, no. 1922 (March 4, 2020): 20192995. http://dx.doi.org/10.1098/rspb.2019.2995.
Анотація:
Intestinal microbiota perform many functions for their host, but among the most important is their role in metabolism, especially the conversion of recalcitrant biomass that the host is unable to digest into bioavailable compounds. Most studies have focused on the assistance gut microbiota provide in the metabolism of carbohydrates, however, their role in host amino acid metabolism is poorly understood. We conducted an experiment on Mus musculus using 16S rRNA gene sequencing and carbon isotope analysis of essential amino acids (AA ESS ) to quantify the community composition of gut microbiota and the contribution of carbohydrate carbon used by the gut microbiome to synthesize AA ESS that are assimilated by mice to build skeletal muscle tissue. The relative abundances of Firmicutes and Bacteroidetes inversely varied as a function of dietary macromolecular content, with Firmicutes dominating when mice were fed low-protein diets that contained the highest proportions of simple carbohydrates (sucrose). Mixing models estimated that the microbial contribution of AA ESS to mouse muscle varied from less than 5% (threonine, lysine, and phenylalanine) to approximately 60% (valine) across diet treatments, with the Firmicute-dominated microbiome associated with the greatest contribution. Our results show that intestinal microbes can provide a significant source of the AA ESS their host uses to synthesize structural tissues. The role that gut microbiota play in the amino acid metabolism of animals that consume protein-deficient diets is likely a significant but under-recognized aspect of foraging ecology and physiology.
36
Vial, Flavie, David W. Macdonald, and Daniel T. Haydon. "Response of endemic afroalpine rodents to the removal of livestock grazing pressure." Current Zoology 57, no. 6 (December 1, 2011): 741–50. http://dx.doi.org/10.1093/czoolo/57.6.741.
Анотація:
Abstract The Bale Mountains of Ethiopia represent the world’s largest continuous extent of afroalpine habitat. With a peak combined density of over 8000 individuals/km2, the endemic giant mole rat Tachyoryctes macrocephalus, Blick’s grass rat Arvicanthis blicki and the brush-furred mouse Lophuromys melanonyx are the dominant wild herbivores within this ecosystem and may be affected by the presence of high densities of domestic livestock. The purpose of this study was to establish whether these endemic rodent populations could respond to the removal of grazing pressure inside three 0.25 hectare livestock exclosures (paired with grazed control plots) and to determine whether such response was mediated through concomitant changes in the vegetation structure. We hypothesised that livestock grazing negatively affects endemic rodent populations through competition or increased predation risk and we predicted an increase in rodent biomass following the removal of grazing pressure. We found no evidence of rodent populations responding to the removal of livestock after fourteen months. The short-term nature of the experimental design, environmental fluctuations and the ecosystem’s inherent stochasticity may explain the apparent lack of a significant response. However, while this study is inconclusive, it emphasises the need for more long-term experimental investigations to assess the effects of domestic grazers on vegetation and on dependent communities. The effects of rapidly increasing livestock numbers in the Bale Mountains will require continued close monitoring of vegetation and endemic animal communities as the afroalpine is altered by external biotic and abiotic forces.
37
Thiam, Mahamadou, Antony Champion, Diaga Diouf, and Mame Ourèye SY. "NaCl Effects on In Vitro Germination and Growth of Some Senegalese Cowpea (Vigna unguiculata (L.) Walp.) Cultivars." ISRN Biotechnology 2013 (July 25, 2013): 1–11. http://dx.doi.org/10.5402/2013/382417.
Анотація:
Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important grain legumes in sub-Saharian regions. It contributes to man food security by providing a protein-rich diet. However, its production is limited by abiotic stresses such as salinity. This study aims to evaluate the salt tolerance of 15 cowpea cultivars, at germination stage. The seed germination process consisted of sowing them in agarified water (8 g·L−1) supplemented with 6 different concentrations of NaCl (0, 10, 50, 100, 150, and 200 mM). Results highlighted that high salt concentrations drastically reduced germination and significantly delayed the process for all varieties. A cowpea varietal effect towards the salt tolerance was noticed. Genotypes Diongoma, 58-78, and 58-191 were more salt-tolerant cultivars while Mougne and Yacine were more salt-sensitive ones as confirmed in the three groups of the dendrogram. NaCl effects on the early vegetative growth of seedlings were assessed with a tolerant (58-191) and a susceptible (Yacine) cultivar. Morphological (length and dry biomass) and physiological (chlorophyll and proline contents) parameter measurements revealed a negative effect of high (NaCl). However, 58-191 was much more salt tolerant, and the chlorophyll and proline contents were higher than those of Yacine genotype at increasing salt concentrations.
38
Heiden, Matthew Vander. "Cellular Bioenergetics in Lymphoid Neoplasia." Blood 118, no. 21 (November 18, 2011): SCI—25—SCI—25. http://dx.doi.org/10.1182/blood.v118.21.sci-25.sci-25.
Анотація:
Abstract Abstract SCI-25 Many cancer cells metabolize glucose by aerobic glycolysis, a phenomenon characterized by increased glycolysis with lactate production and decreased oxidative phosphorylation. We have argued that alterations in cell metabolism associated with cancer may be selected by cancer cells to meet the distinct metabolic needs of proliferation. Unlike metabolism in differentiated cells, which is geared toward efficient ATP generation, the metabolism in cancer cells must be adapted to facilitate the accumulation of biomass. Cancer cells divert a larger fraction of their nutrient metabolism to pathways other than mitochondrial respiration regardless of oxygen availability. Nevertheless, oxygen levels still influence how nutrients are metabolized. We have found that the source of carbon used in various anabolic processes varies based on oxygen levels. Furthermore, the enzymes used to metabolize nutrients can also differ based on the cellular context. This includes regulation of isocitrate dehydrogenase, an enzyme that is mutated in some cancers. There is also strong selection for use of the M2 isoform of pyruvate kinase (PK-M2) to metabolize glucose in cancer cell lines. However, evidence from mouse models suggests that PK-M2 is dispensable for glucose metabolism by many tumors in vivo, suggesting an alternate pathway to convert phosphoenolpyruvate to pyruvate can be used to metabolize glucose. This regulation of pyruvate kinase also plays an important role in hematopoietic stem cell biology. Together, these findings argue that distinct metabolic phenotypes exist among proliferating cells, and both environmental and genetic factors influence how metabolism is regulated to support cell growth. Disclosures: Vander Heiden: Agios Pharmaceuticals: Consultancy, Equity Ownership.
39
Hidalgo, Daniel, Jacob Bejder, Ramona Pop, Kyle Gellatly, Yung Hwang, S. Maxwell Scalf, Anna Eastman, et al. "Epor Stimulates Rapid Cycling and Larger Red Cells during Mouse and Human Erythropoiesis." Blood 138, Supplement 1 (November 5, 2021): 852. http://dx.doi.org/10.1182/blood-2021-154403.
Анотація:
Abstract Erythroid terminal differentiation (ETD) entails cell divisions coupled to decreasing cell size. The tight link between the number of cell divisions and red cell size is apparent in nutritional deficiencies or genetic variants in which fewer cycles result in larger red cells. Here we investigated novel EpoR functions, finding that EpoR signaling disrupts the relationship between cell cycle number and cell size, simultaneously promoting rapid cycling and the formation of larger red cells. EpoR is essential for erythroblast survival, but it is unclear whether it has other non-redundant functions. To address this, we developed a genetic system in which we rescue mouse Epor -/- fetal liver progenitors from apoptosis by transduction with the anti-apoptotic protein Bcl-x L, and compare their ensuing differentiation with that of Epor -/- progenitors rescued with EpoR (Fig 1a). We found that the Bcl-x L survival signal, in the absence EpoR, supported formation of enucleated red cells. However, key ETD features were abnormal. First, Bcl-x L-transduced Epor -/- erythroblasts underwent slower and fewer cell cycles (Figure 1b), differentiating prematurely into enucleated red cells. Premature induction of the cyclin-dependent-kinase inhibitor p27 KIP1 was in part responsible for the fewer cycles in the absence of EpoR signaling. We confirmed that EpoR also stimulates rapid cycling in wild-type erythroblasts in vivo, using a mouse transgenic for a live-cell reporter of cell cycle speed. Second, using imaging flow cytometry, we found that Bcl-x L-transduced Epor -/- erythroblasts were smaller than EpoR-transduced Epor -/- cells (Fig 1c,d). By doubly transducing Epor -/- erythroblasts with both Bcl-x L and EpoR, we verified that EpoR absence, and not Bcl-x L overexpression, is responsible for the smaller size of Bcl-x L-transduced Epor -/- erythroblasts and reticulocytes. Bcl-x L-transduced Epor -/- erythroblasts failed to upregulate the transferrin receptor, suggesting that iron deficiency may be responsible for their smaller size. However, neither iron supplementation, nor transduction with the transferrin receptor, rescued their smaller size. Iron regulates cell size through Heme-regulated eIF2α kinase (HRI). To definitively test the role of iron and HRI, we generated mice doubly deleted for both EpoR and HRI. We then rescued both Epor -/- and Epor -/-Hri -/- -fetal liver cells in parallel, by transduction with either Bcl-x L or EpoR. In agreement with the known role of HRI as a negative regulator of erythroblast size, both Bcl-x L- transduced and EpoR-transduced erythroblasts were larger on the Epor -/-Hri -/- genetic background. However, the difference in size between Bcl-x L and EpoR-rescued erythroblasts persisted in Epor -/-Hri -/- erythroblasts and reticulocytes (Fig 1c,d), conclusively showing that EpoR signaling regulates cell size independently of the HRI pathway. EpoR promoted increased erythroblast and reticulocyte cell size in wild-type mice in vitro and in vivo, in response to Epo concentrations ranging from 10 to 10,000 mU/ml. We also evaluated the effect of Epo on red cell size in humans, in two independent studies, where healthy volunteers were administered Epo for either 3 weeks (20 IU /kg every 48 hours, 25 subjects, Study #1) or for 7 weeks (weekly Epo dosing that increased hemoglobin by 10 -15%; 24 subjects, Study #2). In a third intervention, 21 subjects participated in a randomized double-blind placebo-controlled crossover study in which 900 ml of whole blood was withdrawn from the treatment group by venipuncture. In all three studies, the increase in MCV in the treatment groups persisted long after Epo and reticulocyte levels returned to baseline (Figure 2). There was no correlation between MCV and the reticulocyte count, whose time courses were clearly divergent (r < 0.1, Pearson's product-moment correlation). Further, computational simulation suggests that the extent and duration of the increase in MCV is unlikely to be the result of skewing of the circulating red cell population in favor of younger, larger red cells. Our work reveals a paradoxical EpoR-driven increase in erythroblast cycling simultaneously with increased erythroblast and red cell size. It suggests that EpoR alters the relationship between cell cycle and biomass in erythroblasts. It further suggests that hypoxia, anemia and other high-Epo syndromes are new diagnostic interpretations of increased MCV in the clinic. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.
40
Murtoniemi, Timo, Aino Nevalainen, and Maija-Riitta Hirvonen. "Effect of Plasterboard Composition on Stachybotrys chartarum Growth and Biological Activity of Spores." Applied and Environmental Microbiology 69, no. 7 (July 2003): 3751–57. http://dx.doi.org/10.1128/aem.69.7.3751-3757.2003.
Анотація:
ABSTRACT The effects of plasterboard composition on the growth and sporulation of Stachybotrys chartarum as well as on the inflammatory potential of the spores were studied. S. chartarum was grown on 13 modified plasterboards under saturated humidity conditions. The biomass was estimated by measuring the ergosterol content of the S. chartarum culture while the spore-induced cytotoxicity and production of nitric oxide (NO), tumor necrosis factor alpha (TNF-α), and interleukin-6 in mouse macrophages was used to illustrate the bioactivity of spores. The ergosterol content of S. chartarum correlated with the number of spores collected from plasterboards. The growth and sporulation decreased compared to that of the reference board in those cases where (i) the liner was treated with biocide, (ii) starch was removed from the plasterboard, or (iii) desulfurization gypsum was used in the core. Spores collected from all the plasterboards were toxic to the macrophages. The biocide added to the core did not reduce the growth; in fact, the spores collected from that board evoked the highest cytotoxicity. The conventional additives used in the core had inhibitory effects on growth. Recycled plasterboards used in the core and the board lacking the starch triggered spore-induced TNF-α production in macrophages. In summary, this study shows that the growth of a strain of S. chartarum on plasterboard and the subsequent bioactivity of spores were affected by minor changes to the composition of the core or liners, but it could not be totally prevented without resorting to the use of biocides. However, incomplete prevention of microbial growth by biocides even increased the cytotoxic potential of the spores.
41
Yin, Qi, Siwen Wu, Lei Wu, Zhenling Wang, Yandong Mu, Rui Zhang, Chunyan Dong, et al. "A novel in silico antimicrobial peptide DP7 combats MDR Pseudomonas aeruginosa and related biofilm infections." Journal of Antimicrobial Chemotherapy 75, no. 11 (July 31, 2020): 3248–59. http://dx.doi.org/10.1093/jac/dkaa308.
Анотація:
Abstract Background Antimicrobial peptides are promising alternative antimicrobial agents to combat MDR. DP7, an antimicrobial peptide designed in silico, possesses broad-spectrum antimicrobial activities and immunomodulatory effects. However, the effects of DP7 against Pseudomonas aeruginosa and biofilm infection remain largely unexplored. Objectives To assess (i) the antimicrobial activity of DP7 against MDR P. aeruginosa; and (ii) the antibiofilm activity against biofilm infection. Also, to preliminarily investigate the possible antimicrobial mode of action. Methods The MICs of DP7 for 104 clinical P. aeruginosa strains (including 57 MDR strains) and the antibiofilm activity were determined. RNA-Seq, genome sequencing and cell morphology were conducted. Both acute and chronic biofilm infection mouse models were established. Two mutants, resulting from point mutations associated with LPS and biofilms, were constructed to investigate the potential mode of action. Results DP7, at 8–32 mg/L, inhibited the growth of clinical P. aeruginosa strains and, at 64 mg/L, reduced biofilm formation by 43% to 68% in vitro. In acute lung infection, 0.5 mg/kg DP7 exhibited a 70% protection rate and reduced bacterial colonization by 50% in chronic infection. DP7 mainly suppressed gene expression involving LPS and outer membrane proteins and disrupted cell wall structure. Genome sequencing of the DP7-resistant strain DP7R revealed four SNPs controlling LPS and biofilm production. gshA44 and wbpJ139 mutants displayed LPS reduction and motility deficiency, conferring the reduction of LPS and biofilm biomass of strain DP7R and indicating that LPS was a potential target of DP7. Conclusions These results demonstrate that DP7 may hold potential as an effective antimicrobial agent against MDR P. aeruginosa and related infections.
42
Wang, Ying-Hua, William J. Israelsen, Dongjun Lee, Vionnie W. C. Yu, Nathaniel T. Jeanson, Clary B. Clish, Lewis C. Cantley, Matthew G. Vander Heiden, and David T. Scadden. "Differential Dependence On Aerobic Glycolysis In Normal and Malignant Hematopoietic Stem and Progenitor Cells To Sustain Daughter Cell Production." Blood 122, no. 21 (November 15, 2013): 793. http://dx.doi.org/10.1182/blood.v122.21.793.793.
Анотація:
Abstract How glucose is metabolized can influence cell function, but whether differences in glucose metabolism reflect, or dictate, cell state is not clear and is of particular interest given the association of cancer with aerobic glycolysis. Studies on cancer cell lines have indicated that increased glucose uptake with lactate production regardless of oxygen concentration, a phenomenon also known as the Warburg effect, is promoted in part by expression of the M2 isoform of pyruvate kinase (PKM2) and the muscle form of lactate dehydrogenase A (LDHA). Normal somatic cells thought to also preferentially use glycolytic metabolism are tissue stem cells, particularly the self-renewing hematopoietic stem cells (HSC) resident in the hypoxic microenvironment of the bone marrow. It remains to be defined, however whether proliferating hematopoietic progenitor cells rely on aerobic glycolysis and whether malignant and normal hematopoietic cells are dependent on the same metabolic regulation. We observed that PKM2 and LDHA are the predominant isoforms expressed by all BM hematopoietic cells. To further understand the role of glycolytic metabolism in hematopoiesis and hematological malignancy, we utilized a mouse strain that allows conditional deletion of the PKM2 specific exon 10. Deletion of PKM2 in hematopoetic cells leads to expression of PKM1, accompanied with partial inhibition of lactate production and decreased glycolytic intermediates in the hematopoietic stem/progenitor cell (HSPC) population. Loss of PKM2 compromises the long-term repopulation capacity of HSPCs as revealed by serial transplantation assay. Interestingly, the repopulating defects resulting from PKM2 depletion appear to involve progenitors, perhaps due to inadequate biomass generation necessary for robust cell proliferation. To confirm that the effect of PKM2 deletion on HSPC function is due to metabolic changes rather than other putative PKM2 functions, we engineered a mouse strain that allowed conditional knockout of LDHA to more potently impair aerobic glycolysis. LDHA deletion completely inhibited lactate production, enhanced ROS levels in hematopoietic cells and impaired long-term BM repopulating activity. In contrast to PKM2 deletion that affects progenitor but not stem cells, LDHA depletion impacts both stem cell maintenance and progenitor cell proliferation. Deletion of either PKM2 or LDHA markedly suppressed leukemia initiation by either putative stem cell (BCR-ABL) or progenitor (MLL-AF9) transforming alleles. Therefore, modulating aeroblic glycolysis has effects on normal hematopoietic cells that depend upon cell state and negatively impacts leukemic growth regardless of cell state. The differential sensitivity of normal and malignant cells to modulation of aerobic glycolysis suggests a potential therapeutic opportunity for leukemia intervention. Disclosures: No relevant conflicts of interest to declare.
43
Shafait, Faisal, Euan S. Harvey, Mark R. Shortis, Ajmal Mian, Mehdi Ravanbakhsh, James W. Seager, Philip F. Culverhouse, Danelle E. Cline, and Duane R. Edgington. "Towards automating underwater measurement of fish length: a comparison of semi-automatic and manual stereo–video measurements." ICES Journal of Marine Science 74, no. 6 (February 27, 2017): 1690–701. http://dx.doi.org/10.1093/icesjms/fsx007.
Анотація:
Abstract Underwater stereo–video systems are widely used for counting and measuring fish in aquaculture, fisheries, and conservation management. Length measurements are generated from stereo–video recordings by a software operator using a mouse to locate the head and tail of a fish in synchronized pairs of images. This data can be used to compare spatial and temporal changes in the mean length and biomass or frequency distributions of populations of fishes. Since the early 1990s stereo–video has also been used for measuring the lengths of fish in aquaculture for quota and farm management. However, the costs of the equipment, software, the time, and salary costs involved in post processing imagery manually and the subsequent delays in the availability of length information inhibit the adoption of this technology. We present a semi-automatic method for capturing stereo–video measurements to estimate the lengths of fish. We compare the time taken to make measurements of the same fish measured manually from stereo–video imagery to that measured semi-automatically. Using imagery recorded during transfers of Southern Bluefin Tuna (SBT) from tow cages to grow out cages, we demonstrate that the semi-automatic algorithm developed can obtain fork length measurements with an error of less than 1% of the true length and with at least a sixfold reduction in operator time in comparison to manual measurements. Of the 22 138 SBT recorded we were able to measure 52.6% (11 647) manually and 11.8% (2614) semi-automatically. For seven of the eight cage transfers recorde,d there were no statistical differences in the mean length, weight, or length frequency between manual and semi-automatic measurements. When the data were pooled across the eight cage transfers, there was no statistical difference in mean length or weight between the stereo–video-based manual and semi-automated measurements. Hence, the presented semi-automatic system can be deployed to significantly reduce the cost involved in adoption of stereo–video technology.
44
Man, Cheuk-Him, David T. Scadden, Francois Mercier, Nian Liu, Wentao Dong, Gregory Stephanopoulos, Li Jiang, Yookyung Jung, Charles Lin, and Anskar Y. H. Leung. "Epigenetic Activation of the pH Regulator MCT4 in Acute Myeloid Leukemia Exploits a Fundamental Metabolic Process of Enhancing Cell Growth through Proton Shifting." Blood 134, Supplement_1 (November 13, 2019): 3765. http://dx.doi.org/10.1182/blood-2019-123604.
Анотація:
Acute myeloid leukemia (AML) cells exhibit metabolic alterations that may provide therapeutic targets not necessarily evident in the cancer cell genome. Among the metabolic features we noted in AML compared with normal hematopoietic stem and progenitors (HSPC) was a strikingly consistent alkaline intracellular pH (pHi). Among candidate proton regulators, monocarboxylate transporter 4 (MCT4) mRNA and protein were differentially increased in multiple human and mouse AML cell lines and primary AML cells. MCT4 is a plasma membrane H+and lactate co-transporter whose activity necessarily shifts protons extracellularly as intracellular lactate is extruded. MCT4 activity is increased when overexpressed or with increased intracellular lactate generated by glycolysis in the setting of nutrient abundance. With increased MCT4 activity, extracellular lactate and protons will increase causing extracellular acidification while alkalinizing the intracellular compartment. MCT4-knockout (MCT4-KO) of mouse and human AMLdid not induce compensatory MCT1 expression, reduced pHi, suppressed proliferation and improved animal survival. Growth reduction was experimentally defined to be due to intracellular acidification rather than lactate accumulation by independent modulation of those parameters. MCT4-KOmetabolic profiling demonstrated decreased ATP/ADP and increased NADP+/NADPH suggesting suppression of glycolysis and the pentose phosphate pathway (PPP) that was confirmed by stable isotopic carbon flux analyses. Notably,the enzymatic activity of purified gatekeeper enzymes, hexokinase 1 (HK1), pyruvate kinase M2 isoform (PKM2) and glucose-6-phosphate dehydrogenase (G6PDH) was sensitive to pH with increased activity at the leukemic pHi (pH 7.6) compared to normal pHi (pH 7.3). Evaluating MCT4 transcriptional regulation, we defined that activating histonemarks, H3K27ac and H3K4me3, were enriched at the MCT4 promoter region as were transcriptional regulators MLL1 and Brd4 by ChIP in AML compared with normal cells. Pharmacologic inhibition of Brd4 suppressed Brd4 and H3K27ac enrichment and MCT4 expression in AML and reduced leukemic cell growth. To determine whether MCT4 based pHi changes were sufficient to increase cell proliferation, we overexpressed MCT4 in normal HSPC and demonstrated in vivo increases in growth in conjunction with pHi alkalization. Some other cell types also were increased in their growth kinetics by MCT4 overexpression and pHi increase. Therefore, proton shifting may be a means by which cells respond to nutrient abundance, co-transporting lactate and protons out of the cell, increasing the activity of enzymes that enhance PPP and glycolysis for biomass generation. Epigenetic changes in AML appear to exploit that process by increasing MCT4 expression to enforce proton exclusion thereby gaining a growth advantage without dependence on signaling pathways. Inhibiting MCT4 and intracellular alkalization may diminish the ability of AML to outcompete normal hematopoiesis. Figure Disclosures Scadden: Clear Creek Bio: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Novartis: Other: Sponsored research; Editas Medicine: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Bone Therapeutics: Consultancy; Fog Pharma: Consultancy; Red Oak Medicines: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; LifeVaultBio: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Magenta Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Agios Pharmaceuticals: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Fate Therapeutics: Consultancy, Equity Ownership.
45
Bienek, Diane R., Anthony A. Giuseppetti, Stanislav A. Frukhtbeyn, Rochelle D. Hiers, Fernando L. Esteban Florez, Sharukh S. Khajotia, and Drago Skrtic. "Physicochemical, Mechanical, and Antimicrobial Properties of Novel Dental Polymers Containing Quaternary Ammonium and Trimethoxysilyl Functionalities." Journal of Functional Biomaterials 11, no. 1 (December 18, 2019): 1. http://dx.doi.org/10.3390/jfb11010001.
Анотація:
The aims of this study were to evaluate the physicochemical and mechanical properties, antimicrobial (AM) functionality, and cytotoxic potential of novel dental polymers containing quaternary ammonium and trimethoxysilyl functionalities (e.g., N-(2-(methacryloyloxy)ethyl)-N,N-dimethyl-3-(trimethoxysilyl)propan-1-aminium iodide (AMsil1) and N-(2-(methacryloyloxy)ethyl)-N,N-dimethyl-11-(trimethoxysilyl)undecan-1-aminium bromide (AMsil2)). AMsil1 or AMsil2 were incorporated into light-cured (camphorquinone + ethyl-4-N,N-dimethylamino benzoate) urethane dimethacrylate (UDMA)/polyethylene glycol-extended UDMA/ethyl 2-(hydroxymethyl)acrylate (EHMA) resins (hereafter, UPE resin) at 10 or 20 mass %. Cytotoxic potential was assessed by measuring viability and metabolic activity of immortalized mouse connective tissue and human gingival fibroblasts in direct contact with monomers. AMsil–UPE resins were evaluated for wettability by contact angle measurements and degree of vinyl conversion (DVC) by near infra-red spectroscopy analyses. Mechanical property evaluations entailed flexural strength (FS) and elastic modulus (E) testing of copolymer specimens. The AM properties were assessed using Streptococcus mutans (planktonic and biofilm forms) and Porphyromonas gingivalis biofilm. Neither AMsil exhibited significant toxicity in direct contact with cells at biologically relevant concentrations. Addition of AMsils made the UPE resin more hydrophilic. DVC values for the AMsil–UPE copolymers were 2–31% lower than that attained in the UPE resin control. The mechanical properties (FS and E) of AMsil–UPE specimens were reduced (11–57%) compared to the control. Compared to UPE resin, AMsil1–UPE and AMsil2–UPE (10% mass) copolymers reduced S. mutans biofilm 4.7- and 1.7-fold, respectively (p ≤ 0.005). Although not statistically different, P. gingivalis biofilm biomass on AMsil1–UPE and AM AMsil2–UPE copolymer disks were lower (71% and 85%, respectively) than that observed with a commercial AM dental material. In conclusion, the AM function of new monomers is not inundated by their toxicity towards cells. Despite the reduction in mechanical properties of the AMsil–UPE copolymers, AMsil2 is a good candidate for incorporation into multifunctional composites due to the favorable overall hydrophilicity of the resins and the satisfactory DVC values attained upon light polymerization of AMsil-containing UDMA/PEG-U/EHMA copolymers.
46
van Bruggen, Armando, Sanne Endstra, Gerritje J. W. van der Windt, and Arnon P. Kater. "Impaired Metabolic Fitness in T Cells in Chronic Lymphocytic Leukemia." Blood 128, no. 22 (December 2, 2016): 2528. http://dx.doi.org/10.1182/blood.v128.22.2528.2528.
Анотація:
Abstract Quiescent T cells primarily use oxidative phosphorylation (OXPHOS) to generate ATP, while in response to activation T cells switch to high rates of aerobic glycolysis, also known as the Warburg effect. While less efficient in overall ATP production, this switch to aerobic glycolysis is essential to produce cellular biomass needed for proliferation, and is required for T cell effector functions. In chronic lymphocytic leukemia (CLL) acquired T cell dysregulation occurs independent of treatment with functional impairment and exhaustion of T cells. As tumor-imposed metabolic restrictions in mouse models can mediate T cell hyporesponsiveness during cancer, we hypothesized that in the context of CLL T cell metabolism might be altered. Comparison of gene expression profiles of T cells from patients with CLL and age-matched healthy donors (HD) revealed a highly significant increase in the expression of genes in the OXPHOS pathway (P=3.4*10-15) in the CD8 T cell compartment. In corroboration with these array results, we found that in naïve CD8 T cells in CLL, mitochondrial mass and respiration were significantly increased. In addition, increased mitochondrial ROS production was observed in the naïve CD8 T cell subset. Using Seahorse EFA technology on sorted CD8 T cells from CLL and age-matched HD, we found increased oxygen consumption rates in CLL derived CD8 T cells, indicating increased OXPHOS, while the spare respiratory capacity was lower in these cells, indicating impeded ability to cope with cellular stress. Extracellular acidification rates (ECAR; indicating glycolysis), and uptake of fluorescently labeled glucose were similar in CD8 T cells from CLL patients and HD. Next, we studied the metabolic plasticity of CLL derived T cells by stimulation of PBMCs from CLL patients and age-matched HD using anti-CD3/CD28 antibodies. Two days after stimulation, CLL derived T cells had diminished expression of activation markers CD25 and CD38, which correlated with reduced uptake of fluorescently labeled glucose. Moreover, preliminary Seahorse analysis of the immediate response to stimulation with anti-CD3/CD28 showed a reduced increase in ECAR in CLL derived CD8 T cells, indicating an impairment of the glycolytic switch in these cells. Taken together, these results demonstrate that the metabolic fitness of CD8 T cells is impaired in CLL at resting state and after activation. Boosting T cell metabolism in CLL might therefore improve existing immunotherapies in CLL such as CAR-T cell therapy. This work is funded by VENI and VIDI grants from the Dutch Organisation for Scientific Research, and a Marie Curie Career Integration Grant from the European Union. Disclosures Kater: Celgene: Research Funding.
47
Colard, Martin, Michaël Dussiot, Anaïs Martinez, Carole Peyssonnaux, Patrick Mayeux, Fleur Samantha Benghiat, Pierre Buffet, Olivier Hermine, and Pascal Amireault. "Erythropoietin Downregulates Red Blood Cell Clearance in Mice." Blood 134, Supplement_1 (November 13, 2019): 3524. http://dx.doi.org/10.1182/blood-2019-126768.
Анотація:
Purpose Equilibrium between red blood cells (RBC) production and clearance maintains an appropriate circulating RBC biomass. During anemia or hypoxia, a well-characterized hypoxia-dependent induction of erythropoietin (EPO) synthesis leads to an increase in RBC production. At the other extremity of the RBC lifespan, age-related modifications of RBC properties are expected to be recognized by the mononuclear phagocytic system (MPS) and trigger their clearance. We reasoned that, like RBC production, RBC clearance might be physiologically regulated by hypoxia and therefore that its downregulation could contribute to maintain an appropriate RBC biomass. A mouse model was used to explore specific hypotheses on potential regulatory mechanisms involved in RBC clearance. Material and methods Two steps in vivo biotinylation was used to evaluate the impact of EPO on 3 RBC subpopulations: a young subpopulation (<25 days at treatment initiation) representing the RBC produced, one of intermediate age (25-34 days at treatment initiation) which is neither produced nor eliminated, and an old one (> 34 days at treatment initiation) that is steadily cleared. A model of RBC banking (leucocyte depleted and stored in CPDA solution) was used to evaluate the clearance after transfusion of fluorescently-labeled storage-damaged RBC by flow cytometry. Different recipient models were used to evaluate the impact of specific parameters on RBC clearance including: phlebotomy-induced anemia, normobaric hypoxia, erythropoiesis-stimulating agent (ESA) treatment (darbepoietin), splenectomy, doxorubicin-induced inhibition of erythropoiesis and EPO neutralization (anti-EPO rabbit serum) either alone or in combination. Results Decreased clearance of the oldest subpopulation was observed 2 days after ESA treatment and before the increase in RBC production (7 days). After 20 days of treatment, an increased number of RBC from the oldest subpopulation was detected in circulation confirming that senescent RBC clearance is sensitive to EPO signaling. After transfusion, clearance of storage-damaged RBC is reduced by 30% in anemic recipients when compared to non-anemic recipients. RBC clearance is significantly reduced in hypoxic non-anemic recipients, as soon as 6 hours after the initiation of hypoxia, suggesting that hematocrit per se does not affect RBC clearance. In ESA-treated non-anemic non-hypoxic mice, RBC clearance is also reduced showing that EPO signaling is sufficient. To investigate the role of the spleen in this process, splenectomy was combined with the previous models. As expected, RBC clearance was reduced by 20% in splenectomized recipients. RBC clearance is however even more decreased when splenectomy is combined with anemia, hypoxia or ESA treatment compared to splenectomized or control mice, suggesting that EPO downregulation of RBC clearance is not restricted to the spleen. Erythropoiesis inhibition did not alter the anemia-induced downregulation of RBC clearance ruling out the possibility that an erythroid factor is involved in the process. Finally, neutralization of circulating EPO not only abolishes the reduction of RBC clearance observed in anemic recipients, but also increases RBC clearance in both anemic and non-anemic recipients. Taken together these results indicate that EPO regulates RBC clearance during anemia and in steady state (Figure). Conclusion RBC clearance is downregulated during anemia/hypoxia and EPO is sufficient and necessary to mediate this physiological function. RBC clearance downregulation preceded the increase in production rate induced by ESA treatment suggesting it is a very early physiological response to maintain oxygen supply during anemia. The lifespan of a circulating RBC is therefore adaptable and could be regulated by 2 factors: the RBC pro- and anti-phagocytic properties on one side and, on the other side, the MPS level of activity and sensitivity toward these RBC properties. In case of anemia or hypoxia, increased EPO level would act on the RBC itself, on the activity/sensitivity of the MPS or both to downregulate RBC clearance until the equilibrium between oxygen need and supply is restored. Future studies will evaluate if the pathological dysregulation of this mechanism participates in the pathogenesis of anemia or, modulate transfusion efficacy and burden in chronically transfused patients. Figure Disclosures Buffet: Zimmer Biomet: Research Funding. Hermine:Celgene: Research Funding; Novartis: Research Funding; AB science: Consultancy, Equity Ownership, Honoraria, Research Funding. Amireault:Zimmer Biomet: Research Funding.
48
Damon, Andrea L., Jolyon Jesty, Lesley E. Scudder, Dmitri V. Gnatenko, and Wadie F. Bahou. "Megakaryocyte/Platelet-Restricted FVIII Expression Using a Platelet Factor 4 Promoter: Determination of Activation State and In Vivo Efficacy during Thrombocytosis." Blood 110, no. 11 (November 16, 2007): 1142. http://dx.doi.org/10.1182/blood.v110.11.1142.1142.
Анотація:
Abstract Ectopic delivery of coagulation factor VIII (FVIII) to megakaryocytes (Mk) represents a viable approach for localized tenase generation by effectively concentrating the FVIIIa/FIXa enzyme-cofactor complex onto the negatively-charged phospholipid surface of activated platelets. While phenotypic correction has been demonstrated using hemophilia A (FVIII−/−) murine models in vivo, the activation state of platelet FVIII (pFVIII), optimal promoter choice, and phenotypic correction in the setting of a thrombocytotic stimulus remain unestablished. Preliminary microarray experiments using human platelets (N=5) demonstrated that the Mk-specific platelet factor 4 (PF4) transcripts were among the most abundant, prompting use of the 1.1 Kb PF4 promoter for Mk/platelet-restricted expression of human B-domain-deleted (hBDD) FVIII within the background of an exon 17-deleted mouse model of hemophilia A (PF4/hBDD/FVIII−/−). A chromogenic tenase assay using gel-filtered platelets from PF4/hBDD/FVIII−/− mice confirmed the presence of functional FVIII equivalent to 73 mU·1x109 platelets·mL−1 (N = 10 mice). In contrast, FVIII was not detectable in PF4/hBDD/FVIII−/− plasma (assay sensitivity <20 pM) or in platelets from FVIII−/− mice. The ectopic pFVIII did not affect the release and/or function of other a-granule storage proteins as established by parallel measurements of platelet factor V (FV) using a prothrombinase assay. Paired tenase assays (± thrombin) confirmed that pFVIII (unlike pFV) required thrombin cleavage for complete activation. To delineate the effects of a thrombocytotic stimulus on pFVIII expression and/or function, PF4/hBDD/FVIII−/− (N = 10) or FVIII−/− control mice (N = 5) were injected with thrombopoietin (TPO; 10μg/kg/day for 5 days) resulting in an 87% average increase in platelet count. Day 10 tenase assay of TPO-injected PF4/hBDD/FVIII−/− mice demonstrated a 66% reduction in pFVIII activity (25 mU FVIII·1x109 platelets·mL−1), unassociated with altered expression of a-granule-stored amyloid-b-precursor protein (AbPP) as a control for storage granule content; plasmatic FVIII remained undetectable. In contrast, the decrease in total platelet FVIII biomass was less pronounced in TPO-treated PF4/hBDD/FVIII−/− mice, representing a 35% reduction from 147.6 mU to 96 mU after TPO stimulation. The decreased pFVIII in TPO-stimulated PF4/hBDD/FVIII−/− mice correlated with loss of phenotypic correction as evaluated using tail bleeding survival rates: wild-type mice (100%; N= 5), FVIII−/− (0%; N=5), PF4/hBDD/FVIII−/− (TPO-naïve 60%; N=11), PF4/hBDD/FVIII−/− (TPO-treated 0%; N=7) (p value between PF4/hBDD/FVIII−/− mice with and without TPO stimulation = 0.002). While these data establish that Mk-directed pFVIII (unlike pFV) is proteolytically inactive upon platelet activation, they also imply that thrombocytotic stimuli negatively affect the pFVIII bioavailability and phenotypic efficacy. As importantly, the hemostatic efficacy of platelet FVIII correlates best with localized platelet FVIII delivery (FVIII concentration/platelet) and not the systemic platelet FVIII bioavailability.
49
Riedl, Ruth A., Colin M. L. Burnett, Nicole A. Pearson, John J. Reho, Mohamad Mokadem, Robert A. Edwards, Tammy L. Kindel, John R. Kirby, and Justin L. Grobe. "Gut Microbiota Represent a Major Thermogenic Biomass." Function 2, no. 3 (March 22, 2021). http://dx.doi.org/10.1093/function/zqab019.
Анотація:
Abstract Evidence supports various roles for microbial metabolites in the control of multiple aspects of host energy flux including feeding behaviors, digestive efficiency, and energy expenditure, but few studies have quantified the energy utilization of the biomass of the gut microbiota itself. Because gut microbiota exist in an anoxic environment, energy flux is expected to be anaerobic; unfortunately, commonly utilized O2/CO2 respirometry-based approaches are unable to detect anaerobic energy flux. To quantify the contribution of the gut microbial biomass to whole-animal energy flux, we examined the effect of surgical reduction of gut biomass in C57BL/6J mice via cecectomy and assessed energy expenditure using methods sensitive to anaerobic flux, including bomb and direct calorimetry. First, we determined that cecectomy caused an acceleration of weight gain over several months due to a reduction in combined total host plus microbial energy expenditure, as reflected by an increase in energy efficiency (ie, weight gained per calorie absorbed). Second, we determined that under general anesthesia, cecectomy caused immediate changes in heat dissipation that were significantly modified by short-term pretreatment with dietary or pharmaceutical interventions known to modify the microbiome, and confirmed that these effects were undetectable by respirometry. We conclude that while the cecum only contributes approximately 1% of body mass in the mouse, this organ contributes roughly 8% of total resting energy expenditure, that this contribution is predominantly anaerobic, and that the composition and abundance of the cecal microbial contents can significantly alter its contribution to energy flux.
50
Upadhyaya, Hari D., Lihua Wang, Chudamani Sharma Prakash, Yanlong Liu, Li Gao, Ruirui Meng, K. Seetharam, et al. "Genome-Wide Association Mapping Identifies an SNF4 Ortholog that Impacts Biomass, Plant Height, SSC and Juice Yield in Sorghum and Sugarcane." Journal of Experimental Botany, March 15, 2022. http://dx.doi.org/10.1093/jxb/erac110.
Анотація:
Abstract Sorghum is feed/industrial crop in the developed countries and a staple food in the rest of the world. In this study, we evaluated the sorghum mini core (MC) collection for days to 50% flowering (DF), biomass (BM), plant height (PH), soluble solid content (SSC) and juice weight (JW) and the sorghum reference set (RS) for DF and PH in 7-12 testing environments and performed association mapping with 6,094,317 SNP markers in the MC and 265,500 SNPs for the RS. We identified in the MC panel three QTLs for DF, one for PH, one for BM, and two for JW. In the RS panel we identified another PH QTL on chromosome 6 also associated with DF, BM, JW, and SSC in the MC panel. Transgenic studies of three genes selected from the locus revealed that Sobic.006G061100 (SbSNF4-2) increased BM, SSC, JW, and PH when overexpressed in both sorghum and sugarcane and delayed flowering in transgenic sorghum. SbSNF4-2 encodes a γ subunit of the evolutionarily conserved AMPK/SNF1/SnRK1 heterotrimeric complexes and overexpression of human or mouse γ2 in heart or the whole body also increases heart or body biomass. SbSNF4-2 and its orthologs will be valuable in genetic enhancement of biomass and sugar yield in plants.