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1
Yuen, C. B., and Teresa Li. "Value of Professional Property Managers in Residential Project Development." Nang Yan Business Journal 4, no. 1 (June 1, 2016): 56–67. http://dx.doi.org/10.1515/nybj-2016-0005.
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Abstract Property management has often been described as an after-sale service because the participation of professional property managers is only required upon completion of the building. Recently, however, property management has become an integral part of project development based on its value. These days, managing recreational facilities such as residents’ clubs, gyms and swimming pools, given the frequent use of electronic installations, no longer falls under basic caretaking services. The early detection of hidden problems such as poor quality concealed cables, conduits and pipes and the improper selection of building materials saves time and money in subsequent maintenance and repair work, simultaneously reducing any inconvenience experienced by end-users due to a breakdown in services or defective rectification. Environmental protection and energy conservation are becoming increasingly important in our daily lives, and thus are unavoidable agendas in the design and construction of buildings, be they domestic, commercial or industrial. The input of professional property managers based on their foresight and past work experience with end-users is crucial to the success of such schemes. This paper reviews the value of professional property managers in residential project development.
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Pietkun-Greber, Izabela, and Dariusz Suszanowicz. "The consequences of the inappropriate use of ventilation systems operating in indoor swimming pool conditions - analysis." E3S Web of Conferences 45 (2018): 00064. http://dx.doi.org/10.1051/e3sconf/20184500064.
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Increasingly more leisure facilities, such as water parks or indoor swimming pools are being built in Poland nowadays. In order to ensure the air quality required by standards for such leisure facilities it is necessary to fit them with effectively functioning ventilation. For the removal of excess humidity, as well as chlorine ions occurring as a result of the disinfection of water as well as the carbon dioxide emitted by people using the facility, the ventilation system needs to be appropriately designed and efficient. For this reason, studies into the air quality in such facilities were undertaken. The paper presents the causes and consequences of the inappropriate operation and maintenance of ventilation systems in swimming pools. The study found that the causes of deterioration in the technical condition of the system which was operated in an environment with chlorine ions were: an inappropriate manufacture of its components and the wrong choice of construction materials for the given environment of operation. Furthermore, failure to follow the manufacturer's guidelines for the operation and maintenance of the components of the ventilation system greatly precipitated its degradation and the occurrence of sick building syndrome in the swimming pool. Solutions were found and proposed in order to improve the efficiency of the ventilation system in the given swimming-pool facility.
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Joce, R. E., J. Bruce, D. Kiely, N. D. Noah, W. B. Dempster, R. Stalker, P. Gumsley, et al. "An outbreak of cryptosporidiosis associated with a swimming pool." Epidemiology and Infection 107, no. 3 (December 1991): 497–508. http://dx.doi.org/10.1017/s0950268800049190.
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SUMMARYIn August 1988 an increase was noted in the number of cases of cryptosporidiosis identified by the microbiology laboratory at Doncaster Royal Infirmary. By 31 October, 67 cases had been reported. Preliminary investigations implicated the use of one of two swimming pools at a local sports centre and oocysts were identified in the pool water. Inspection of the pool revealed significant plumbing defects which had allowed ingress of sewage from the main sewer into the circulating pool water. Epidemiological investigation confirmed an association between head immersion and illness. The pools were closed when oocysts were identified in the water and extensive cleaning and repair work was undertaken. The pool water was retested for cryptosporidial oocysts and found to be negative before the pool re-opened.
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PODEWILS, L. J., L. ZANARDI BLEVINS, M. HAGENBUCH, D. ITANI, A. BURNS, C. OTTO, L. BLANTON, et al. "Outbreak of norovirus illness associated with a swimming pool." Epidemiology and Infection 135, no. 5 (November 1, 2006): 827–33. http://dx.doi.org/10.1017/s0950268806007370.
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SUMMARYOn 3 February 2004, the Vermont Department of Health received reports of acute gastroenteritis in persons who had recently visited a swimming facility. A retrospective cohort study was conducted among persons attending the facility between 30 January and 2 February. Fifty-three of 189 (28%) persons interviewed developed vomiting or diarrhoea within 72 h after visiting the facility. Five specimens tested positive for norovirus and three specimen sequences were identical. Entering the smaller of the two pools at the facility was significantly associated with illness (RR 5·67, 95% CI 1·5–22·0,P=0·012). The investigation identified several maintenance system failures: chlorine equipment failure, poorly trained operators, inadequate maintenance checks, failure to alert management, and insufficient record keeping. This study demonstrates the vulnerability of recreational water to norovirus contamination, even in the absence of any obvious vomiting or faecal accident. Our findings also suggest that norovirus is not as resistant to chlorine as previously reported in experimental studies. Appropriate regulations and enforcement, with adequate staff training, are necessary to ensure recreational water safety.
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Elmas, Sait, Aneta Pospisilova, Aneta Anna Sekulska, Vasil Vasilev, Thomas Nann, Stephen Thornton, and Craig Priest. "Photometric Sensing of Active Chlorine, Total Chlorine, and pH on a Microfluidic Chip for Online Swimming Pool Monitoring." Sensors 20, no. 11 (May 30, 2020): 3099. http://dx.doi.org/10.3390/s20113099.
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A microfluidic sensor was studied for the photometric detection of active chlorine, total chlorine, and pH in swimming pool samples. The sensor consisted of a four-layer borosilicate glass chip, containing a microchannel network and a 2.2 mm path length, 1.7 mL optical cell. The chip was optimised to measure the bleaching of methyl orange and spectral changes in phenol red for quantitative chlorine (active and total) and pH measurements that were suited to swimming pool monitoring. Reagent consumption (60 mL per measurement) was minimised to allow for maintenance-free operation over a nominal summer season (3 months) with minimal waste. The chip was tested using samples from 12 domestic, public, and commercial swimming pools (indoor and outdoor), with results that compare favourably with commercial products (test strips and the N,N’-diethyl-p-phenylenediamine (DPD) method), precision pH electrodes, and iodometric titration.
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Karni, Eyal. "Retractable Spatial Structures for Swimming Pool Enclosures." International Journal of Space Structures 10, no. 4 (December 1995): 231–36. http://dx.doi.org/10.1177/026635119501000405.
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Retractable spatial structures are modern buildings designed to comply with the user's flexibility needs – concerning the complete or partial opening of a building's enclosure. Most sport activities are usually preferred, by spectators as well as by competitors, to be held in open air. Swimming, a popular sport activity, is highly sensitive to cold and wind. The need for retractable structures arises since weather conditions vary with seasons while current market demand is for year-round activity. Designing retractable enclosures for swimming pools involves specific criteria, resulting from the safety and operational demands of such facilities. The variety of swimming pool geometries and the nature of the user's needs has resulted in numerous solutions of retractable enclosures, varying in size, geometry, structural systems, building technology, opening and closing techniques, building materials, maintenance and cost. This paper addresses current solutions of light-weight retractable spatial structures – designed to enclose swimming pool facilities. Swimming pool types are described, followed by a list of design criteria. Classification of structural methods is then brought forward, represented by specific projects and drawings.
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Adriaenssens, S. "Feasibility Study of Medium Span Spliced Spline Stressed Membranes." International Journal of Space Structures 23, no. 4 (November 2008): 243–51. http://dx.doi.org/10.1260/026635108786959889.
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This papers examines the feasibility of 3 medium span (16m – 32m) spliced spline stressed membranes. Medium span slender arch systems have been used for canopy structures of stadia cladding such as the Gottlieb-Daimler Stadium. Lateral bracing by the membrane means that the arch can be slender and flexible. Flexibility and lightness fit in well with the design of pre-stressed structures that are themselves flexible and adjust to applied loads. The presented membrane structures are designed bearing in mind their deployability (as necessary for temporary tents) and offer a good simple alternative to medium span high maintenance pneumatics covering squash courts or swimming pools.
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Berg, Alvyn P., Ting-An Fang, and Hao L. Tang. "Variability of residual chlorine in swimming pool water and determination of chlorine consumption for maintaining hygienic safety of bathers with a simple mass balance model." Journal of Water and Health 17, no. 2 (December 26, 2018): 227–36. http://dx.doi.org/10.2166/wh.2018.217.
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Abstract Trial-and-error chlorination as a conventional practice for swimming pool water disinfection may fail to consistently maintain the pool's residual chlorine within regulatory limits. This study explored the variability of residual chlorine and other common water quality parameters of two sample swimming pools and examined the potential of using a mass balance model for proactive determination of chlorine consumption to better secure the hygienic safety of bathers. A lightly loaded Pool 1 with a normalized bather load of 0.038 bather/m3/day and a heavily loaded Pool 2 with a normalized bather load of 0.36 bather/m3/day showed great variances in residual free and combined chlorine control by trial-and-error methods due to dynamic pool uses. A mass balance model based on chemical and physical chlorine consumption mechanisms was found to be statistically valid using field data obtained from Pool 1. The chlorine consumption per capita coefficient was determined to be 4120 mg/bather. The predictive method based on chlorine demand has a potential to be used as a complementary approach to the existing trial-and-error chlorination practices for swimming pool water disinfection. The research is useful for pool maintenance to proactively determine the required chlorine dosage for compliance of pool regulations.
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SMARAND, Bogdan, Ana-Ruxandra TOMA, and Ana-Maria DUMITRESCU. "SISTEM AUTOMAT DE MONITORIZARE ȘI DOZARE A APEI DINTR-UN BAZIN." "ACTUALITĂŢI ŞI PERSPECTIVE ÎN DOMENIUL MAŞINILOR ELECTRICE (ELECTRIC MACHINES, MATERIALS AND DRIVES - PRESENT AND TRENDS)" 2020, no. 1 (February 10, 2021): 1–9. http://dx.doi.org/10.36801/apme.2020.1.2.
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Measurement, dosing, and control systems for liquids are based on applications dedicated to measuring the amount of liquid, controlled filling of enclosures and disinfection of liquids and surfaces. The applications of such a system are multiple, from maintaining the quality of drinking water to the maintenance of swimming pools and can be extended to the food and pharmaceutical industries. This paper presents an experimental setup for monitoring and controlling water in an aquarium, and it was made with commercially available elements, which have a low cost and with microcontrollers specific to the development boards. The system is controlled with the help of development boards and has a didactic purpose, the paper presenting the process of choosing the components and the development of the application.
10
Santarius, Megan, Chang Ho Lee, and Richard A. Anderson. "Supervised membrane swimming: small G-protein lifeguards regulate PIPK signalling and monitor intracellular PtdIns(4,5)P2 pools." Biochemical Journal 398, no. 1 (July 27, 2006): 1–13. http://dx.doi.org/10.1042/bj20060565.
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Regulation of PIPK (phosphatidylinositol phosphate kinase) and PtdIns(4,5)P2 signalling by small G-proteins and their effectors is key to many biological functions. Through selective recruitment and activation of different PIPK isoforms, small G-proteins such as Rho, Rac and Cdc42 modulate actin dynamics and cytoskeleton-dependent cellular events in response to extracellular signalling. These activities affect a number of processes, including endocytosis, bacterial penetration into host cells and cytolytic granule-mediated targeted cell killing. Small G-proteins and their modulators are also regulated by phosphoinositides through translocation and conformational changes. Arf family small G-proteins act at multiple sites as regulators of membrane trafficking and actin cytoskeletal remodelling, and regulate a feedback loop comprising phospholipase D, phosphatidic acid, PIPKs and PtdIns(4,5)P2, contributing to enhancement of PtdIns(4,5)P2-mediated cellular events and receptor signalling. Na+, Kir (inwardly rectifying K+), Ca2+ and TRP (transient receptor potential) ion channels are regulated by small G-proteins and membrane pools of PtdIns(4,5)P2. Yeast phosphatidylinositol 4-phosphate 5-kinases Mss4 and Its3 are involved in resistance against disturbance of sphingolipid biosynthesis and maintenance of cell integrity through the synthesis of PtdIns(4,5)P2 and downstream signalling through the Rom2/Rho2 and Rgf1/Rho pathways. Here, we review models for regulated intracellular targeting of PIPKs by small G-proteins and other modulators in response to extracellular signalling. We also describe the spatial and temporal cross-regulation of PIPKs and small G-proteins that is critical for a number of cellular functions.
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Harrell, W. Andrew. "Lifeguards' Vigilance: Effects of Child-Adult Ratio and Lifeguard Positioning on Scanning by Lifeguards." Psychological Reports 84, no. 1 (February 1999): 193–97. http://dx.doi.org/10.2466/pr0.1999.84.1.193.
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Observers recorded visual scanning by four lifeguards at three indoor public swimming pools. Scanning increased as a positive function of the ratio of children to adult swimmers, i.e., scanning was greater when the ratio was high, suggesting that lifeguards became more concerned about the risks to children and the ability of nearby adult swimmers to monitor these children when the number of children significantly exceeded the number of adults. Absolute numbers of children, however, decreased number of scans, possibly because of greater number of incidents and rule violations requiring lifeguards' attention which competed with watching the pool. Lifeguards were more likely to scan a pool area when they were in elevated towers versus standing on the pool decks. Lifeguards' scanning declined later in the day, possibly due to fatigue or because of competing activities of pool maintenance.
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Coggins, Si’Ana A., Bijan Mahboubi, Raymond F. Schinazi, and Baek Kim. "SAMHD1 Functions and Human Diseases." Viruses 12, no. 4 (March 31, 2020): 382. http://dx.doi.org/10.3390/v12040382.
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Deoxynucleoside triphosphate (dNTP) molecules are essential for the replication and maintenance of genomic information in both cells and a variety of viral pathogens. While the process of dNTP biosynthesis by cellular enzymes, such as ribonucleotide reductase (RNR) and thymidine kinase (TK), has been extensively investigated, a negative regulatory mechanism of dNTP pools was recently found to involve sterile alpha motif (SAM) domain and histidine-aspartate (HD) domain-containing protein 1, SAMHD1. When active, dNTP triphosphohydrolase activity of SAMHD1 degrades dNTPs into their 2′-deoxynucleoside (dN) and triphosphate subparts, steadily depleting intercellular dNTP pools. The differential expression levels and activation states of SAMHD1 in various cell types contributes to unique dNTP pools that either aid (i.e., dividing T cells) or restrict (i.e., nondividing macrophages) viral replication that consumes cellular dNTPs. Genetic mutations in SAMHD1 induce a rare inflammatory encephalopathy called Aicardi–Goutières syndrome (AGS), which phenotypically resembles viral infection. Recent publications have identified diverse roles for SAMHD1 in double-stranded break repair, genome stability, and the replication stress response through interferon signaling. Finally, a series of SAMHD1 mutations were also reported in various cancer cell types while why SAMHD1 is mutated in these cancer cells remains to investigated. Here, we reviewed a series of studies that have begun illuminating the highly diverse roles of SAMHD1 in virology, immunology, and cancer biology.
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Allin, C. J., and R. W. Wilson. "Behavioural and metabolic effects of chronic exposure to sublethal aluminum in acidic soft water in juvenile rainbow trout (Oncorhynchus mykiss)." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 4 (April 1, 1999): 670–78. http://dx.doi.org/10.1139/f99-002.
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Triplicate groups of 15 softwater-acclimated juvenile rainbow trout (Oncorhynchus mykiss) were randomly allocated to one of three treatments: pH 6.5 with no aluminum, pH 5.2 with no aluminum, and pH 5.2 with 30 µg labile aluminum·L-1. The aluminum dose was sublethal and continued for 34 days. Treatment effects on swimming behaviour, metabolism, feeding, food conversion efficiency, and blood parameters were determined. Fish exposed to aluminum displayed hypoactivity that was statistically distinct from both control groups from day 1 onwards. Exposure to acid alone elicited no behavioural effects. There were no significant differences in metabolic rates between the treatment groups. Feeding rates of the fish exposed to aluminum became depressed, reaching a minimum on day 15, and gradually recovered thereafter, but never to the preexposure levels. Swimming behaviour was a more sensitive index of exposure to aluminum than feeding. Fish exposed to aluminum had significantly fewer red blood cells and lower haematocrit than the controls, indicating haemodilution. Aluminum is known to act as a respiratory toxicant, restricting aerobic scope. In addition, these data suggest that fish respond to aluminum exposure by reducing metabolically costly activities such as routine swimming behaviour to allow for the increased maintenance costs associated with acclimation and damage repair.
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Heberden, Christine. "Modulating adult neurogenesis through dietary interventions." Nutrition Research Reviews 29, no. 2 (July 1, 2016): 163–71. http://dx.doi.org/10.1017/s0954422416000081.
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AbstractThree areas in the brain continuously generate new neurons throughout life: the subventricular zone lining the lateral ventricles, the dentate gyrus in the hippocampus and the median eminence in the hypothalamus. These areas harbour neural stem cells, which contribute to neural repair by generating daughter cells that then become functional neurons or glia. Impaired neurogenesis leads to detrimental consequences, such as depression, decline of cognitive abilities and obesity. Adult neurogenesis is a versatile process that can be modulated either positively or negatively by many effectors, external or endogenous. Diet can modify neurogenesis both ways, either directly by ways of food-borne molecules, or possibly by the modifications induced on gut microbiota composition. It is therefore critical to define dietary strategies optimal for the maintenance of the stem cell pools.
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Essers, Jeroen, Arjan F. Theil, Céline Baldeyron, Wiggert A. van Cappellen, Adriaan B. Houtsmuller, Roland Kanaar, and Wim Vermeulen. "Nuclear Dynamics of PCNA in DNA Replication and Repair." Molecular and Cellular Biology 25, no. 21 (November 1, 2005): 9350–59. http://dx.doi.org/10.1128/mcb.25.21.9350-9359.2005.
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ABSTRACT The DNA polymerase processivity factor proliferating cell nuclear antigen (PCNA) is central to both DNA replication and repair. The ring-shaped homotrimeric PCNA encircles and slides along double-stranded DNA, acting as a “sliding clamp” that localizes proteins to DNA. We determined the behavior of green fluorescent protein-tagged human PCNA (GFP-hPCNA) in living cells to analyze its different engagements in DNA replication and repair. Photobleaching and tracking of replication foci revealed a dynamic equilibrium between two kinetic pools of PCNA, i.e., bound to replication foci and as a free mobile fraction. To simultaneously monitor PCNA action in DNA replication and repair, we locally inflicted UV-induced DNA damage. A surprisingly longer residence time of PCNA at damaged areas than at replication foci was observed. Using DNA repair mutants, we showed that the initial recruitment of PCNA to damaged sites was dependent on nucleotide excision repair. Local accumulation of PCNA at damaged regions was observed during all cell cycle stages but temporarily disappeared during early S phase. The reappearance of PCNA accumulation in discrete foci at later stages of S phase likely reflects engagements of PCNA in distinct genome maintenance processes dealing with stalled replication forks, such as translesion synthesis (TLS). Using a ubiquitination mutant of GFP-hPCNA that is unable to participate in TLS, we noticed a significantly shorter residence time in damaged areas. Our results show that changes in the position of PCNA result from de novo assembly of freely mobile replication factors in the nucleoplasmic pool and indicate different binding affinities for PCNA in DNA replication and repair.
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De Filippis, Patrizia, Cinzia Mozzetti, Massimo Amicosante, Gian Loreto D'Alò, Alessandra Messina, Donatella Varrenti, Roberto Giammattei, et al. "Occurrence of Legionella in showers at recreational facilities." Journal of Water and Health 15, no. 3 (March 20, 2017): 402–9. http://dx.doi.org/10.2166/wh.2017.296.
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Critical environments, including water systems in recreational settings, represent an important source of Legionella pneumophila infection in humans. In order to assess the potential risk for legionellosis, we analyzed Legionella contamination of water distribution systems in 36 recreational facilities equipped with swimming pools. One hundred and sixty water samples were analyzed from shower heads or taps located in locker rooms or in bathrooms. By culture method and polymerase chain reaction, 41/160 samples were positive for Legionella from 12/36 recreational centers. Hotels (57.1%) and sports centers (41.2%) were the most contaminated. L. pneumophila serotypes 2–14 (25/41) were more frequently found than serotype 1 (10/41). Samples at temperature ≥30 °C were more frequently positive than samples at temperature <30 °C (n = 39 vs n = 2, p < 0.00001). The presence of L. pneumophila was investigated by comparison with heterotrophic plate count (HPC), an indicator of water quality. The presence of L. pneumophila was associated more frequently with high and intermediate HPC load at 37 °C, therefore should be considered a potential source when HPC at 37 °C is >10 CFU/mL. Maintenance, good hygiene practices, interventions on the hydraulic system and regular controls must be implemented to minimize exposure to L. pneumophila infection risk.
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Morris, Gerald W., Tyler A. Iams, Kira G. Slepchenko, and Edward E. McKee. "Origin of pyrimidine deoxyribonucleotide pools in perfused rat heart: implications for 3′-azido-3′-deoxythymidine-dependent cardiotoxicity." Biochemical Journal 422, no. 3 (August 27, 2009): 513–20. http://dx.doi.org/10.1042/bj20082427.
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In adult non-replicating tissues such as heart, demand for dNTPs (deoxynucleoside triphosphates) is low but essential for mitochondrial DNA replication and nuclear DNA repair. dNTPs may be synthesized from salvage of deoxyribonucleosides or by reduction of ribonucleotides. We have hypothesized that the cardiac mitochondrial toxicity of the nucleoside analogue AZT (3′-azido-3′-deoxythymidine; known as zidovudine) is caused by inhibition of thymidine kinase 2 of the salvage pathway and subsequent TTP pool depletion. The extent to which this hypothesis has merit depends on how much the heart relies on thymidine phosphorylation for maintenance of the TTP pool. In the present study, we used isotopic tracing to demonstrate that both TTP and dCTP are solely synthesized by phosphorylation of thymidine and deoxycytidine respectively, with no evidence for synthesis from other precursors. We have also shown that UTP and CTP are synthesized by phosphorylation of uridine and cytidine respectively, with no detectable role for the de novo pyrimidine synthesis pathway. Lastly, we have demonstrated that AZT decreased the TTP pool by 50% in 30 min of perfusion, while having no effect on other dNTPs. In summary, the present study demonstrated that adult rat heart has a limited mechanism for dCTP and TTP synthesis and thus these pools may be more sensitive than replicating cells to drugs such as AZT that affect the salvage pathway.
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Mardawa, I. Gede, Ervina Ahyudanari, and Suryawan Murtiadi. "Karakteristik Marshall pada Campuran Aspal Dingin dengan Asbuton Akibat Dari Penggunaan Aditif Wetfix-BE." JURNAL SAINS TEKNOLOGI & LINGKUNGAN 6, no. 1 (June 7, 2020): 50. http://dx.doi.org/10.29303/jstl.v6i1.149.
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West Nusa Tenggara Province consists of two main islands namely Lombok and Sumbawa. Regency Roads on Lombok Island, especially rural roads, has been severely damaged due to lack of routine maintenance. The types of damage that occur are cracks, small holes, and even large pools that endanger road users. This study aims to obtain a mixture of new materials in order to obtain an easy and fast repair method without reducing the quality during its intended life. In the meantime, repairing with CAD (cold asphalt mixture) requires curing time of 3x24 hours to achieve standard material quality with Marshall Characteristics according to the 2010 Bina Marga Specifications. This study combines CAD using BP (rejuvenating agent) and Wetfix-BE additive to get optimal results without curing process. The BP used is asphalt mixture, kerosene, and bunker oil stirred in a mixing machine into one unit. The results showed the optimum concentration of this mixture was 0.3% wet-be additive, 4.50% BP in CAD with asbuton proportion of 25%. In the fatigue test with a cyclic loading of 100 kPa, the pavement mixture is able to resist a fully loaded truck of 7731 times. In conclusion, this mixture combination is able to speed up the asphalt binding time by making briquettes according to the 2018 Highways Specifications without going through the long curing process.
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Löllgen, Stefanie, and Hans Weiher. "The role of the Mpv17 protein mutations of which cause mitochondrial DNA depletion syndrome (MDDS): lessons from homologs in different species." Biological Chemistry 396, no. 1 (January 1, 2015): 13–25. http://dx.doi.org/10.1515/hsz-2014-0198.
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Abstract Mitochondrial DNA depletion syndromes (MDDS) are severe pediatric diseases with diverse clinical manifestations. Gene mutations that underlie MDDS have been associated with alterations in the mitochondrial DNA (mtDNA) replication machinery or in mitochondrial deoxyribonucleoside triphosphate pools. However, the nuclear gene MPV17, whose mutated forms are associated with hepatocerebral MDDS in humans, plays a so-far unknown role in mtDNA maintenance. A high degree of conservation has been determined between MPV17 and its mouse (Mpv17), zebrafish (tra) and yeast (SYM1) homologs, respectively, whereby mutants in these cause very different phenotypes. While dysfunction in this gene in humans causes fatal liver disease, kidney pathology is induced in mice. Moreover, in zebrafish inactivation of the Mpv17 homolog was detected as a viable dyscolouration mutant. Knock out of the yeast ortholog results in a temperature-sensitive metabolic growth phenotype. Detailed analyses on common denominators between these different phenotypes strengthen the hypothesis that the Mpv17 protein forms a channel in the inner mitochondrial membrane, allowing small molecules – in vertebrates probably nucleotides, and in yeast probably intermediates of the tricarboxylic acid cycle – to pass. Moreover, a function modifying the pathologic manifestations of MPV17-related disease in mice has been identified. This signaling pathway remarkably involves the non-mitochondrial catalytic subunit of DNA-dependent protein kinase (PRKDC), important in double-strand break repair resistance against reactive oxygen-induced genotoxic stress.
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Laczko, Rozalia, and Katalin Csiszar. "Lysyl Oxidase (LOX): Functional Contributions to Signaling Pathways." Biomolecules 10, no. 8 (July 22, 2020): 1093. http://dx.doi.org/10.3390/biom10081093.
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Cu-dependent lysyl oxidase (LOX) plays a catalytic activity-related, primary role in the assembly of the extracellular matrix (ECM), a dynamic structural and regulatory framework which is essential for cell fate, differentiation and communication during development, tissue maintenance and repair. LOX, additionally, plays both activity-dependent and independent extracellular, intracellular and nuclear roles that fulfill significant functions in normal tissues, and contribute to vascular, cardiac, pulmonary, dermal, placenta, diaphragm, kidney and pelvic floor disorders. LOX activities have also been recognized in glioblastoma, diabetic neovascularization, osteogenic differentiation, bone matrix formation, ligament remodeling, polycystic ovary syndrome, fetal membrane rupture and tumor progression and metastasis. In an inflammatory context, LOX plays a role in diminishing pluripotent mesenchymal cell pools which are relevant to the pathology of diabetes, osteoporosis and rheumatoid arthritis. Most of these conditions involve mechanisms with complex cell and tissue type-specific interactions of LOX with signaling pathways, not only as a regulatory target, but also as an active player, including LOX-mediated alterations of cell surface receptor functions and mutual regulatory activities within signaling loops. In this review, we aim to provide insight into the diverse ways in which LOX participates in signaling events, and explore the mechanistic details and functional significance of the regulatory and cross-regulatory interactions of LOX with the EGFR, PDGF, VEGF, TGF-β, mechano-transduction, inflammatory and steroid signaling pathways.
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Strømland, Øyvind, Marc Niere, Andrey A. Nikiforov, Magali R. VanLinden, Ines Heiland, and Mathias Ziegler. "Keeping the balance in NAD metabolism." Biochemical Society Transactions 47, no. 1 (January 9, 2019): 119–30. http://dx.doi.org/10.1042/bst20180417.
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Abstract Research over the last few decades has extended our understanding of nicotinamide adenine dinucleotide (NAD) from a vital redox carrier to an important signalling molecule that is involved in the regulation of a multitude of fundamental cellular processes. This includes DNA repair, cell cycle regulation, gene expression and calcium signalling, in which NAD is a substrate for several families of regulatory proteins, such as sirtuins and ADP-ribosyltransferases. At the molecular level, NAD-dependent signalling events differ from hydride transfer by cleavage of the dinucleotide into an ADP-ribosyl moiety and nicotinamide. Therefore, non-redox functions of NAD require continuous biosynthesis of the dinucleotide. Maintenance of cellular NAD levels is mainly achieved by nicotinamide salvage, yet a variety of other precursors can be used to sustain cellular NAD levels via different biosynthetic routes. Biosynthesis and consumption of NAD are compartmentalised at the subcellular level, and currently little is known about the generation and role of some of these subcellular NAD pools. Impaired biosynthesis or increased NAD consumption is deleterious and associated with ageing and several pathologies. Insults to neurons lead to depletion of axonal NAD and rapid degeneration, partial rescue can be achieved pharmacologically by administration of specific NAD precursors. Restoring NAD levels by stimulating biosynthesis or through supplementation with precursors also produces beneficial therapeutic effects in several disease models. In this review, we will briefly discuss the most recent achievements and the challenges ahead in this diverse research field.
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Park, Ji Hye, Robert S. Welner, Daniel G. Tenen, and Catherine T. Yan. "Lig4 Is Essential for Maintaining HSC Homeostasis." Blood 124, no. 21 (December 6, 2014): 606. http://dx.doi.org/10.1182/blood.v124.21.606.606.
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Abstract Blood cells of all lineages are generated from small pools of long-term hematopoietic stem cells (LT-HSCs) that continually replenish throughout life. LT-HSCs regulate the balanced turnover of all mature blood lineages by switching between self-renewal, differentiation and quiescence, thereby maintaining hematopoietic homeostasis in steady state and in response to injury. In any given cell, some DNA damage may remain despite the action of DNA repair processes, including in LT-HSCs. Over time, HSCs lose their long-term capability to self-renew due to misrepair of DNA breaks and increased accumulation of DNA damage, resulting in loss of regenerative plasticity and immune fitness. The accrual of DNA damage is the principal factor that contributes to functional decline in HSC renewal and in the immune system during ageing. In recent studies, the capacity of aging HSCs to self-renew is shown to be dependent on DNA repair pathways, with non-homologous end-joining (NHEJ) as the principle pathway implicated in DNA repair in quiescent HSCs from ex-vivo cell-based assays. Although NHEJ in particular has been implicated in this process in LT-HSCs, there has so far been very little evidence of this activity in vivo. DNA Ligase IV (Lig4), which catalyzes the end-ligation of broken DNA ends mediated by NHEJ, has no known functions outside of NHEJ. Because a deficiency in Lig4 in mice is embryonic lethal, here we assessed the role of Lig4 in HSC homeostasis by assaying HSC functions in a knockin mouse model of a hypomorphic homozygous R278H mutation in Lig4 that had been identified in the first DNA Lig4 Syndrome patient. The R278H mutation significantly impairs the end-ligation function of the Lig4 protein, and mice homozygous for the R278H mutation (Lig4R/R) showed diminished DSB repair capacity and age-dependent lymphopenia that implicated potential HSC defects. Consistent with a defect in NHEJ, we show the Lig4 R278H mutation severely limited HSC self-renewal. Lig4R/R HSC reconstitutions were skewed towards the myeloid lineage and resulted in severely reduced chimerism, confirming the capacity of HSCs to self-renew requires functional DNA repair. Next, we examined if there is increased DNA damage with/without ionizing irradiation (IR). Lig4R/R LT-HSCs showed an increase in reactive oxygen species (ROS), abnormal cycling and increased apoptosis from accumulated DNA damage in steady state and slow DNA double strand breaks (DSBs) repair kinetics in response to low dose IR because of improper Lig4 function. This led us to check the LT-HSC pool more carefully. It has been shown that the HSC pool is intact and phenotypically increased with age. Strikingly, we found that the HSCs in both young and old Lig4R/R mice are markedly reduced to 20% of wild-type levels. The severe LT-HSC reduction and lethality of disease in Lig4R/Rmice was completely rescued by transplantation with wild type bone marrow. These evidences support the notion of a critical role for Lig4 in maintenance of the LT-HSC pool. In a recent study, it was reported that the steady state pool of murine adult LT-HSCs can be further distinguished into quiescent (~20%) and variably cycling (~80%) populations. Since LT-HSCs in young Lig4R/R mice are maintained in steady state at 20% of WT HSCs, we hypothesized that the reduced pool of LT-HSCs in the Lig4R/R mice is caused by the loss of cycling LT-HSCs that continually replenish blood lineages during aging. To compare these populations, microarray analysis was done on the pool of WT and Lig4R/R LT-HSCs, versus sorted populations of quiescent and variably cycling LT-HSCs. Microarray analysis clearly showed that the Lig4R/RLT-HSCs correlated with the quiescent LT-HSCs, indicating NHEJ regulates the homeostasis of the faster cycling LT-HSC pool. Our study suggest that the slowest cycling LT-HSCs serve to replenish the overall LT-HSC pool and HSC homeostasis is maintained by capacity of faster cycling LT-HSC pool to revert to quiescence in response to stress/injury. Additionally, defective NHEJ depletes the faster cycling LT-HSC pool and underlies early HSC exhaustion in Lig4R/R mice. Our findings demonstrate for the first time a physiological role for Lig4 in the maintenance of HSC homeostasis. Disclosures No relevant conflicts of interest to declare.
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Akhtyamov, I. F., V. I. Aidarov, and E. R. Khasanov. "Current methods of rehabilitation after arthroscopic reconstruction of the anterior cruciate ligament of the knee joint (review of literature)." Genij Ortopedii 27, no. 1 (February 2021): 121–27. http://dx.doi.org/10.18019/1028-4427-2021-27-1-121-127.
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Introduction The leading method for treating patients with injuries of the anterior cruciate ligament is its reconstruction. Although this operation is a common procedure, the issues of rehabilitation have not been fully studied. The aim of study Collection and analysis of available published studies on current methods of rehabilitation treatment after arthroscopic reconstruction of the anterior cruciate ligament. Materials and methods We analyzed the publications that were devoted to current methods of rehabilitation treatment of patients after arthroscopic reconstruction of the anterior cruciate ligament. The materials were searched for in the PubMed and Web of Science databases using the keywords “anterior cruciate ligament reconstruction”, “anterior cruciate ligament rehabilitation”. Inclusion criteria were compliance with the general topic, relevance, introduction of new rehabilitation treatments. Studies published earlier than the last 10 years were excluded. Results The analysis found that the main rehabilitation treatments used in patients after reconstruction of the anterior cruciate ligament are of protective character (wearing a functional orthosis or other immobilizing appliance, dosed walking with crutches) and physical activity (complex of exercises, swimming). The most effective way to prevent contractures is early activation of the limb and the maintenance of muscle tone. In turn, the main task of immobilization is prevention or relief of pain. Our study proposes the authors’ methods of rehabilitation which can be used for restorative treatment and accelerate the process of ligament repair. The work includes rehabilitation procedures performed at home after reconstruction of the anterior cruciate ligament under the supervision of a rehabilitation instructor. Discussion Rehabilitation of patients after reconstruction of the anterior cruciate ligament is a necessary complement to surgical treatment. Fast recovery of patients and a full return to an active lifestyle depend on a proper rehabilitation program.
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Sun, Zhihong, Yan Shen, and Ülo Niinemets. "Responses of isoprene emission and photochemical efficiency to severe drought combined with prolonged hot weather in hybrid Populus." Journal of Experimental Botany 71, no. 22 (September 30, 2020): 7364–81. http://dx.doi.org/10.1093/jxb/eraa415.
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Abstract Isoprene emissions have been considered as a protective response of plants to heat stress, but there is limited information of how prolonged heat spells affect isoprene emission capacity, particularly under the drought conditions that often accompany hot weather. Under combined long-term stresses, presence of isoprene emission could contribute to the maintenance of the precursor pool for rapid synthesis of essential isoprenoids to repair damaged components of leaf photosynthetic apparatus. We studied changes in leaf isoprene emission rate, photosynthetic characteristics, and antioxidant enzyme activities in two hybrid Populus clones, Nanlin 1388 (relatively high drought tolerance) and Nanlin 895 (relatively high thermotolerance) that were subjected to long-term (30 d) soil water stress (25% versus 90% soil field capacity) combined with a natural heat spell (day-time temperatures of 35–40 °C) that affected both control and water-stressed plants. Unexpectedly, isoprene emissions from both the clones were similar and the overall effects of drought on the emission characteristics were initially minor; however, treatment effects and clonal differences increased with time. In particular, the isoprene emission rate only increased slightly in the Nanlin 895 control plants after 15 d of treatment, whereas it decreased by more than 5-fold in all treatment × clone combinations after 30 d. The reduction in isoprene emission rate was associated with a decrease in the pool size of the isoprene precursor dimethylallyl diphosphate in all cases at 30 d after the start of treatment. Net assimilation rate, stomatal conductance, the openness of PSII centers, and the effective quantum yield all decreased, and non-photochemical quenching and catalase activity increased in both control and water-stressed plants. Contrary to the hypothesis of protection of leaf photosynthetic apparatus by isoprene, the data collectively indicated that prolonged stress affected isoprene emissions more strongly than leaf photosynthetic characteristics. This primarily reflected the depletion of isoprene precursor pools under long-term severe stress.
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Coetzee, N., O. Edeghere, J. M. Orendi, R. Chalmers, and L. Morgan. "A swimming pool-associated outbreak of cryptosporidiosis in Staffordshire, England, October to December 2007." Eurosurveillance 13, no. 45 (November 6, 2008). http://dx.doi.org/10.2807/ese.13.45.19028-en.
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In October 2007 an increase in laboratory-confirmed cryptosporidiosis cases in Staffordshire, England prompted an outbreak investigation. Case ascertainment included interviewing suspected cases and contacts and obtaining faecal specimens from those with diarrhoea for laboratory identification. Over a three-month period we identified 57 cases of cryptosporidiosis (39 confirmed) distributed across 36 households. The majority of cases (69%) were younger than 20 years. The most plausible exposure was multiple swimming episodes (56% of cases) in 13 local public swimming pools. One large swimming pool was most frequently visited by swimmers and considered a significant contributor to transmission because of substandard filtration and maintenance systems. Control measures focused on inspecting and improving operating standards at swimming pools, hygiene information to swimmers, and early detection and exclusion of cases. The rapid case investigation described in this paper provided adequate information for the early detection and control of a typical seasonal swimming pool related cryptosporidiosis outbreak. Ensuring adequate filtration standards at public swimming pools particularly before the high use periods of late summer and autumn remains a priority.
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Furdal, Kim. "Halbyggeri mellem fag, politik og økonomi." Forum for Idræt 20, no. 1 (August 17, 2004). http://dx.doi.org/10.7146/ffi.v20i1.31709.
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Sports hall construction caught between the profession, politics and the purseThis article looks at the political processes that from 1948 onwards led to the eventual construction of Aabenraa Swimming Pool and Sports Centre in the period 1971-73. The article concludes that it was the persistent demands of local people effectively supported by sporting organisations that at several crucial points made local politicians work towards the establishment of a swimming pool and in the end of a sports centre. As a result of the very slow political decision-making process, the politicians’ wishes and requirements for a swimming pool were overtaken not only by technological developments but also by the increasing demands of the welfare state for public bathing facilities, and this led in the mid-1960s to a violent schism in the town council. While at the end of the 1950s open air bathing and swimming pools could be regarded as providing the basic framework for elementary swimming instruction to prevent people drowning at the seaside, swimming pools developed during the 1960s into the welfare state’s alternative to public beaches. When in 1968 it at last became possible to unite the different views as to the purpose of the swimming pool, Friluftsloven (the Open Air Act) of the same year ended up playing a central role in the construction and maintenance of the centre. This, combined with ideologically based requirements that sport should be party to financing the construction of sports centres, still plays a decisive role today in determining the degree to which sports associations can make more substantial sporting investments in, for example, competitive sport.
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Aguiar, Ana, Caroline Oliveira Silveira, Mari Todero Winck, and Marilise Rott. "Susceptibility of Acanthamoeba to multipurpose lens-cleaning solutions." Acta Parasitologica 58, no. 3 (January 1, 2013). http://dx.doi.org/10.2478/s11686-013-0143-9.
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AbstractThe present study investigated the susceptibility of Acanthamoeba spp. trophozoites to two multipurpose systems for cleaning and maintenance of contact lenses. Three strains of trophozoites from the ATCC (A. castellani T4, A. castellani Neff, and A. polyphaga) and two Acanthamoeba isolates obtained from swimming pools (PT5 and PO1) were placed in monoxenic culture. To test their survival in cleaning solutions for contact lenses, the trophozoites were exposed for 4 and 24 h to two multipurpose solutions (A and B), and were then inoculated into a new monoxenic culture. Amoebic growth on the plates was observed after 72 h of incubation. Trophozoites from all three ATCC strains and one isolate from a swimming pool (PO1) grew in all plates after 4 h of exposure to solutions A and B. After 24 h, the ATCC strains and the PO1 isolate showed growth in most of the plates treated. Only the PT5 isolate showed susceptibility to both solutions over the time intervals tested. The two solutions were not completely effective against most strains and isolates over the time intervals tested. These results are important, since species of Acanthamoeba are widely distributed in the environment and are potential agents of eye pathologies.
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Parsidi. "Pentingnya Housekeeping bagi Suatu Hotel." Media Wisata 2, no. 2 (May 22, 2021). http://dx.doi.org/10.36276/mws.v2i2.34.
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The general public tends to think of Housekeeping as the Department that: makes the head, empties the ashtray and waste basked, tidies up the bathroom and leaves fresh towels. The truth of the matter is of course that it takes more manpower to accomplish. Housekeeping's almost countless function than those of any other Department in the lodging industry. Housekeeping's responsibility may begin with fabrics, and progress to the selection and purchase of all furniture and furnishings; it encompasses not only their cleaning but their maintenance, repair, refurbishment and eventual replacement. Areas of concern include: sleeping rooms, meeting rooms, halls and elevator, all considered "front of the house" The designation also includes all other public areas from lobbies to washrooms to restaurant and cocktail lounges. Outdoor areas such as pools and patios. Housekeeping also oversees almost the entire "back of the house", from locker rooms to employee dining, virtually everything.
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Schmidt, Tobias T., Sushma Sharma, Gloria X. Reyes, Anna Kolodziejczak, Tina Wagner, Brian Luke, Anders Hofer, Andrei Chabes, and Hans Hombauer. "Inactivation of folylpolyglutamate synthetase Met7 results in genome instability driven by an increased dUTP/dTTP ratio." Nucleic Acids Research, October 24, 2019. http://dx.doi.org/10.1093/nar/gkz1006.
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Abstract The accumulation of mutations is frequently associated with alterations in gene function leading to the onset of diseases, including cancer. Aiming to find novel genes that contribute to the stability of the genome, we screened the Saccharomyces cerevisiae deletion collection for increased mutator phenotypes. Among the identified genes, we discovered MET7, which encodes folylpolyglutamate synthetase (FPGS), an enzyme that facilitates several folate-dependent reactions including the synthesis of purines, thymidylate (dTMP) and DNA methylation. Here, we found that Met7-deficient strains show elevated mutation rates, but also increased levels of endogenous DNA damage resulting in gross chromosomal rearrangements (GCRs). Quantification of deoxyribonucleotide (dNTP) pools in cell extracts from met7Δ mutant revealed reductions in dTTP and dGTP that cause a constitutively active DNA damage checkpoint. In addition, we found that the absence of Met7 leads to dUTP accumulation, at levels that allowed its detection in yeast extracts for the first time. Consequently, a high dUTP/dTTP ratio promotes uracil incorporation into DNA, followed by futile repair cycles that compromise both mitochondrial and nuclear DNA integrity. In summary, this work highlights the importance of folate polyglutamylation in the maintenance of nucleotide homeostasis and genome stability.
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Letyushev, A. N., and T. F. Stepanova. "Activity of the Epidemic Process of Enterobiasis in the Russian Federation." ЗДОРОВЬЕ НАСЕЛЕНИЯ И СРЕДА ОБИТАНИЯ - ЗНиСО / PUBLIC HEALTH AND LIFE ENVIRONMENT, May 2020, 57–64. http://dx.doi.org/10.35627/2219-5238/2020-326-5-57-64.
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Relevance: The article describes the results of studying the activity of the epidemic process of enterobiasis, the most common parasitic disease in the Russian Federation. Our objective was to give a comprehensive assessment of the epidemic process of enterobiasis in the country based on the official data on the incidence of pinworm infection in the population and the results of parasitological studies of environmental media conducted in 2010–2017. Materials and methods: Using the methods of variation statistics, we estimated the dynamics of enterobiasis incidence and prevalence rates, studied the differences in the prevalence of enterobiasis detected during testing of suspected cases and of the general population for preventive purposes and epidemic reasons. Results: We established the role of pinworm infection in the structure of parasitic diseases, identified age groups and regions with the highest incidence and prevalence rates of enterobiasis. We observed significant differences in the prevalence of enterobiasis between Russian federal districts. The analysis of the ongoing sanitary parasitological studies helped reveal the regions of the country with a high and low frequency of detecting pinworm eggs in environmental media and the key factors activating the mechanism of transmission of pinworm eggs. Conclusions: We established that in some regions the pinworm infection was spread through the use of swimming pools, while in others it disseminated mainly through contaminated surfaces of various environmental media. At the same time, the estimated statistically significant decrease in the frequency of detecting pinworm eggs in swabs from environmental objects demonstrates the improvement of the sanitary and hygienic condition (maintenance) of epidemically significant facilities (educational establishments and other institutions).
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Dishakjian, Vahe, Daniel M. T. Fessler, and Adam Maxwell Sparks. "Live Fast, Die Young, and Sleep Later: Life History Strategy and Human Sleep Behavior." Evolution, Medicine, and Public Health, December 2, 2020. http://dx.doi.org/10.1093/emph/eoaa048.
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Abstract Background and objectives Life History Theory (LHT) describes trade-offs that organisms make with regard to three investment pathways: growth, maintenance, and reproduction. In light of the reparative functions of sleep, we examine sleep behaviors and corresponding attitudes as proximate manifestations of an individual’s underlying relative prioritization of short-term reproduction versus long-term maintenance. Methodology We collected survey data from 568 participants across two online studies having different participant pools. We use a mixture of segmented and hierarchical regression models, structural equation modeling, and machine learning to infer relationships between sleep duration/quality, attitudes about sleep, and biodemographic/psychometric measures of life history strategy (LHS). Results An age-mediated U- or V-shaped relationship appears when LHS is plotted against habitual sleep duration, with the fastest strategies occupying the sections of the curve with the highest mortality risk: < 6.5 hours (short sleep) and > 8.5 hours (long sleep). LH “fastness” is associated with increased sleepiness and worse overall sleep quality: delayed sleep onset latency, more wakefulness after sleep onset, higher sleep-wake instability, and greater sleep duration variability. Hedonic valuations of sleep may mediate the effects of LHS on certain sleep parameters. Conclusions and implications The costs of deprioritizing maintenance can be parameterized in the domain of sleep, where “life history fastness” corresponds with sleep patterns associated with greater senescence and mortality. Individual differences in sleep having significant health implications can thus be understood as components of lifelong trajectories likely stemming from calibration to developmental circumstances. Relatedly, hedonic valuations of sleep may constitute useful avenues for non-pharmacological management of chronic sleep disorders. LAY Summary Sleep is essential because it allows the body to repair and maintain itself. But time spent sleeping is time that cannot be spent doing other things. People differ in how much they prioritize immediate rewards, including sociosexual opportunities, versus long-term goals. In this research, we show that individual differences in sleep behaviors, and attitudes toward sleep, correspond with psychological and behavioral differences reflecting such differing priorities. Orientation toward sleep can thus be understood as part of the overall lifetime strategies that people pursue.
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Emidio, G. D., F. Konstantinidou, P. G. Artini, V. Gatta, and C. Tatone. "P–175 Possible role of NAD+ metabolism in oocyte aging: insights from gene expression profiles in reproductive aged oocytes." Human Reproduction 36, Supplement_1 (July 1, 2021). http://dx.doi.org/10.1093/humrep/deab130.174.
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Abstract Study question Does reproductive aging alter the expression of genes involved in NAD+ metabolism in the mammalian oocyte? Summary answer We found that aging alters the expression of thirty genes encoding for NAD+-producing and NAD+-consuming enzymes pathway in mouse MII oocytes. What is known already NAD, a multifunctional metabolite in living cells, is known to convert between its oxidized NAD+ and reduced NADH forms during nutrients breakdown; the intracellular NAD+/NADH redox state reflects cell ability in generating ATP energy. NAD+ is utilized by proteins that control gene expression, DNA repair, apoptosis, mitochondrial biogenesis (i.e. sirtuins). Raising NAD+ by inducing its biosynthesis leads to sirtuins activation, so directly linking the cellular redox state with signalling events. The NAD+ pool is set by a critical balance between NAD+ biosynthetic and NAD+ consuming pathways. NAD(P)H levels declined in aged oocytes and NAD+ precursors seem to counteract ovarian aging. Study design, size, duration Pools of 25 oocytes at MII stage were obtained from young (4–8 weeks) and reproductively aged (48–52 weeks) CD–1 mice and processed for the analysis of 41 genes participating in NAD+ biosynthetic and NAD+ consuming pathways NAD+ pathways. Each experiment was performed three times and data were subjected to bioinformatic analysis to unravel potential age-related effects on NAD metabolism. Participants/materials, setting, methods Mice were superovulated by intraperitoneal injection of PMSG followed by hCG 48h apart. MII oocytes were isolated by 0.3 mg/ml hyaluronidase. RNA was obtained from each sample by Arcturus PicoPure Kit, and reverse transcribed. Each cDNA was analysed in triplicate by employing a NAD Metabolism H41 Predesigned panel for use with SYBR® Green, containing 41 genes of the NAD pathway, 2 housekeeping genes and 6 control probes. Raw data were analysed by DataAssist software. Main results and the role of chance The comparison between aged and young oocytes were focused on genes showing an absolute fold change (FC) <0.7 or > 1.4, a present call in at least the 50% of experiments and a p-Value <0.05 (ANOVA). Excluding transcripts showing a concordant value < 80%, n.30 differentially expressed genes (DEGs) were found: n.26 transcripts down-expressed and n.4 genes up-regulated. Data obtained by Ingenuity Pathways Analysis (IPA) software (Ingenuity Systems) provide evidence that NAD+ biosynthesis in aged oocytes is severely compromised. Limitations, reasons for caution Our results on animal model must be taken with caution. Validation of NAD+ precursor or activators of NAD+ biosynthesis in vivo administration is required. Wider implications of the findings: Present results demonstrate that aging affect oocyte genes involved in the regulation of NAD+ availability and supports the hypothesis that modulation of NAD+ metabolism may be an “anti-aging” strategy. Overall, these data laid the foundation for a central role of NAD+ metabolism in the maintenance of oocyte competenc Trial registration number Not applicable