Academic literature on the topic 'Metabolism'
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Journal articles on the topic "Metabolism"
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Anton-Păduraru, Dana-Teodora. "URGENŢE METABOLICE – PARTEA I." Romanian Journal of Pediatrics 64, no. 1 (March 31, 2015): 44–47. http://dx.doi.org/10.37897/rjp.2015.1.9.
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Frecvent, bolnavii cu afecţiuni metabolice (boli datorate dezechilibrelor electrolitice, disfuncţii endocrine, boli înnăscute de metabolism) prezintă simptome similare cu ale altor urgenţe, în particular în perioada de nou-născut şi sugar. Autorii prezintǎ principalele urgenţe: în cazul dezechilibrelor electrolitice – hipoglicemia, hiponatremia, acidoza metabolicǎ şi hipocalcemia neonatalǎ; în cazul disfuncţiilor endocrine – insuficienţa suprarenalianǎ şi criza hipopituitarǎ neonatalǎ; în bolile înnăscute de metabolism – acidoza, hiperglicemia/ hipoglicemia, hiperamoniemia, simptomele clinice asociate acestora şi tratamentul recomandat.
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Kordyum, E. L., and О. М. Nedukha. "Proposals for the ISS: «Starch» Experiment Structural-metabolic aspects of carbohydrate metabolism in microgravity." Kosmìčna nauka ì tehnologìâ 6, no. 4 (July 30, 2000): 97. http://dx.doi.org/10.15407/knit2000.04.972.
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Strashok, L. A., O. V. Buznytska, and О. М. Meshkova. "Indicators of lipid metabolism disorders in the blood serum of adolescents with metabolic syndrome." Ukrainian Biochemical Journal 92, no. 6 (December 24, 2020): 137–42. http://dx.doi.org/10.15407/ubj92.06.137.
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Šnejdrlová, Michaela. "Metabolism and sex, sex and metabolism." Urologie pro praxi 18, no. 1 (March 1, 2017): 22–25. http://dx.doi.org/10.36290/uro.2017.006.
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Wahyono, Sri, Sulistyoweni Widanarko, Setyo S. Moersidik, and Surna T. Djajadiningrat. "METABOLISME PENGELOLAAN SAMPAH ORGANIK MELALUI TEKNOLOGI KOMPOSTING DI WILAYAH INTERNAL PERKOTAAN." Jurnal Teknologi Lingkungan 13, no. 2 (December 13, 2016): 179. http://dx.doi.org/10.29122/jtl.v13i2.1417.
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Kegiatan komposting sampah kota umumnya tidak berjalan sinambung karena kegagalan pasar, lemahnya dukungan pemerintah, lemahnya manajemen dan ketidaklayakan teknik yang digunakan. Penelitian ini bertujuan menyusun konsep metabolisme pengelolaan sampah organik melalui teknologi komposting di wilayah internal perkotaan. Metodologi penelitian ini dilakukan dengan metode kuntitatif dan eksploratif deskriptif melalui analisis matematis, analisis multikriteria pengambilan keputusan, analisis aliran material, dan analisis finansial. Penelitian menyimpulkan bahwa metabolisme pengelolaan sampah organik melalui teknologi komposting di wilayah internal perkotaan adalah metabolism sistem fisik, sosial, dan ekonomi dari kegiatan pengelolaan sampah organik yang bercirikan metabolisme antropogenik untuk keberlanjutan kota sedang. Kata kunci: Pengelolaan sampah organik, metabolisme, aliran material, komposting, analisis multikriteria. AbstractComposting of municipal solid waste activities generally do not run continuously because of market failure, lack of government support, poor management and inability of the techniques used. This study aims to develop the concept of the metabolism of organic waste management through composting technology in internal urban areas. Theresearch methodology was conducted by the method of quantitative and descriptive explorative through mathematical analysis, multicriteria decision analysis, material flow analysis, and financial analysis. The study concluded that the metabolism of organic waste management through composting technology in internal urban areas is themetabolism system of physical, social, economic and environmental of organic waste management activities characterized by anthropogenic metabolism to the sustainability of medium cities. Key words: Organic waste management, metabolism, material flow, composting, analysis of multicriteria
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Litvyak, V. S., and V. V. Litvyak. "Possible Explanation of Metabolism Process." Nutrition and Food Processing 5, no. 1 (February 1, 2022): 01–13. http://dx.doi.org/10.31579/2637-8914/073.
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Until now, there is no hypothesis explaining metabolic processes. At present, only timid assumptions have been put forward about the possibility of the existence of biotransmutation in microorganisms. We have proposed a hypothesis explaining metabolic processes in a living organism. The main stages of the organization of energy flows of matter (action or effort) and antimatter (counteraction or anti-effort) are shown step by step on the basis of their interaction: the forces of complementary and related attraction. Demonstrated the formation of particle-nucleons (looped energy sweats) → electrons → electromagnetic waves → hydrogen proton → development of the hydrogen atom. The periodic table of chemical elements is considered as the gradual development of the hydrogen atom. According to the hypothesis put forward, any «living» body (subcellular organelles, cell, tissue, organ, organ systems, organism: bacteria, plants, fungi, animals, humans) is a set of proteins-enzymes, hormones and other biologically active substances (water, fats, carbohydrates, vitamins, etc.), is intended for the maximum possible acceleration of atomic (or corpuscular) synthesis (conflict-free ordering of previously separated energy flows of action and reaction) as a result of metabolic processes. The whole variety of chemical reactions (compounds, decomposition, substitution, ion exchange, redox, etc.) can be considered as a means for the classification (separation) of different types of electrons and protons, as well as for their delivery to the place of transmutation (active center of the protein -enzyme or hormone) along pathways built from biologically active substances (water, vitamins, fats, etc.). Any failures in the transmutation process immediately manifest themselves in the form of various pathological conditions (diseases). Consideration of «living» organisms as objects carrying out transmutation of chemical elements will make it possible to understand fundamentally new biochemistry, metabolic processes, therapeutic approaches to the treatment of various diseases, dietology, nutritional science, food quality and safety, etc.
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Bayer, Milan. "Phospho-calcium metabolism disorders." Česko-slovenská pediatrie 80, no. 2 (May 20, 2025): 68–75. https://doi.org/10.55095/cspediatrie2025/008.
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Pospisilik, J. Andrew. "Metabolism shaping chromatin shaping metabolism." Cellular and Molecular Life Sciences 70, no. 9 (March 9, 2013): 1493–94. http://dx.doi.org/10.1007/s00018-013-1292-6.
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Umbu Henggu, Krisman, and Yopi Nurdiansyah. "Review dari Metabolisme Karbohidrat, Lipid, Protein, dan Asam Nukleat." QUIMICA: Jurnal Kimia Sains dan Terapan 3, no. 2 (August 2, 2022): 9–17. http://dx.doi.org/10.33059/jq.v3i2.5688.
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Artikel review ini mengulas tentang prinsip dan proses metabolisme karbohidrat, lipid, protein dan asam nukeat pada organisme. Telaah pustaka yang disajikan dalam review ini bersumber pada jurnal ilmiah maupun buku terakreditasi yang relevan. Lintasan metabolisme karbohidrat, lipid, protein, asam nukleat terdiri atas tiga bentuk lintasan yakni katabolik, anabolik dan amfibolik. Lintasan tersebut umumnya terjadi pada mitokondria melalui siklus Krebs. Katabolisme protein, karbohidrat dan lemak dapat menjadi derivat asam amino, glukosa, gliserol dan asam lemak yang mampu dikonversi menjadi energi maupun cadangan energi untuk proses pertumbuhan dan perkembangan sel. Demikian sebaliknya proses anabolisme dapat memanfaatkan derivat makro molekul (asam amino, glukosa, fruktosa, asam lemak) menjadi makro molekul (protein, karbohidrat dan lipid). Proses metabolisme karbohidrat secara khusus melalui glikolisis, glikogenesis dan glukoneogenesis. Sedangkan metabolisme lemak melalui proses asetil-KoA terkarboksilase dan menghasilkan malonil-KoA hingga berlanjut pada proses pembentukan asam lemak melalui proses enzimatis (elongase dan desaturase). Demikian pula pada metabolisme protein yang diawali dengan pemecahan makro molekul dalam bentuk peptida menjadi monomer terkecil (asam amino) secara enzimatis (melibatkan enzim protease) dan menjadi salah satu sumber energi dalam pembentukan ATP untuk perkembangan sel. Sebaliknya anabolisme protein tersebut didasari oleh proses transmisi dan aminasi. Metabolisme asam nukleat melibatkan proses sintesis purin dan pirimidin sebagai nukleotida secara de novo. Proses metabolisme asam nukleat melaui proses enzimatik (housekeeping) yang sangat bertanggungjawab terhadap fungsi katabolisme dan anabolisme.
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Hao, Min, De Ji, Lin Li, Lianlin Su, Wei Gu, Liya Gu, Qiaohan Wang, Tulin Lu, and Chunqin Mao. "Mechanism of Curcuma wenyujin Rhizoma on Acute Blood Stasis in Rats Based on a UPLC-Q/TOF-MS Metabolomics and Network Approach." Molecules 24, no. 1 (December 27, 2018): 82. http://dx.doi.org/10.3390/molecules24010082.
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Rhizome of Curcuma wenyujin, which is called EZhu in China, is a traditional Chinese medicine used to treat blood stasis for many years. However, the underlying mechanism of EZhu is not clear at present. In this study, plasma metabolomics combined with network pharmacology were used to elucidate the therapeutic mechanism of EZhu in blood stasis from a metabolic perspective. The results showed that 26 potential metabolite markers of acute blood stasis were screened, and the levels were all reversed to different degrees by EZhu preadministration. Metabolic pathway analysis showed that the improvement of blood stasis by Curcuma wenyujin rhizome was mainly related to lipid metabolism (linoleic acid metabolism, ether lipid metabolism, sphingolipid metabolism, glycerophospholipid metabolism, and arachidonic acid metabolism) and amino acid metabolisms (tryptophan metabolism, lysine degradation). The component-target-pathway network showed that 68 target proteins were associated with 21 chemical components in EZhu. Five metabolic pathways of the network, including linoleic acid metabolism, sphingolipid metabolism, glycerolipid metabolism, arachidonic acid metabolism, and steroid hormone biosynthesis, were consistent with plasma metabolomics results. In conclusion, plasma metabolomics combined with network pharmacology can be helpful to clarify the mechanism of EZhu in improving blood stasis and to provide a literature basis for further research on the therapeutic mechanism of EZhu in clinical practice.
Dissertations / Theses on the topic "Metabolism"
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Beard, Katherine F. M. "Investigating metabolite channelling in primary plant metabolism." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:8172377f-5eca-4825-b6f1-5c10f02bede5.
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The tricarboxylic acid (TCA) cycle is one of the central pathways in respiration and also plays an important role in a variety of metabolic processes including the synthesis of secondary metabolites and the provision of carbon skeletons for ammonium assimilation and amino acid biosynthesis. Effective regulation of these multiple demands on the TCA cycle is likely to be very important for plant fitness. One way that this regulation could be achieved is through metabolite channelling. This occurs when metabolites are transferred between enzyme active sites without diffusing into the bulk aqueous phase of the cell, and is known to be important in regulating demands in metabolic pathways. Although there is evidence that metabolite channelling exists in animals, there have been no attempts to investigate it in plant. The first aim of this thesis was therefore to investigate whether metabolite channelling exists in the plant TCA cycle. Isotope dilution experiments were developed to investigate metabolite channelling, and were able to show that metabolite channelling was present between certain enzymes of the TCA cycle in both S. tuberosum and A. thaliana mitochondria. The second aim of the thesis was investigate whether metabolite channelling is important in regulating the TCA cycle in plant mitochondria. The pattern of metabolite channelling did not change in mitochondria isolated from the light and the dark, or from mitochondria with increased or decreased TCA cycle rates, but it was not possible to say whether the metabolite channelling altered in a quantitative fashion. Overall the thesis provides the first direct evidence of channelling in the TCA cycle in plants, and further work should help to elucidate what role, if any, it plays.
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Eichler, Paula. "Diminuição da proteína GLUT4 em tecido adiposo de ratos tratados com injeções subcutâneas de óleos de soja ou de girassol." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-16092008-115901/.
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Tratamos ratos por 7 dias com injeções subcutâneas de óleos de soja (S) ou de girassol (G). Verificamos o desenvolvimento de resistência insulínica, com diminuição de GLUT4 e de sua translocação no tecido adiposo de ratos tratados com estes óleos, apesar de aumento no RNAm de GLUT4 no músculo e no tecido adiposo. O tratamento com girassol diminuiu RNAm de GLUT1 no adiposo, onde também diminuiu a quantidade de RNAm de NF-<font face=\"symbol\">kB. (outros fatores transcricionais não apresentaram alteração: PPAR<font face=\"symbol\">g, MEF2A e MF2D). Dosamos ácidos graxos no plasma, fígado (sem alterações), músculo (palmitoléico aumentou no grupo G; linolênico diminuiu no S e G e araquidônico aumentou no S) e adiposo (palmítico e esteárico aumentaram e linoleico diminuiu nos grupos S e G, além de aumentar a proporção saturados/ insaturados).<br>We treated rats for 7 days with subcutaneous soybean (SB) oil or sunflower (SF)oil injections. Insulin resistance was developed, with a decrease in GLUT4 quantity and translocation in adipose tissue in the rats treated with those oils, despite GLUT4 mRNA increase in muscle and adipose tissue. Sunflower treatment led to decrease in GLUT1mRNA in adipose tissue, where NF- <font face=\"symbol\">kB mRNA was also decreased (other transcriptional factors did not change: PPAR<font face=\"symbol\">g, MEF2A e MF2D). Fatty acids were measured in the plasma, the liver (no changes), muscle (palmitoleic increased in SF, linolenic decreased in SB and SF and arachidonic increased in SB) and adipose tissue (palmitic and stearic increased and linoleico decreased in SB and SF, besides increasing in saturated/ unsaturated ratio.
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Bojanowska, Magdalena. "Wpływ opóźniania terminu pierwszego unasieniania krów z zaburzeniami metabolizmu energetycznego na ich płodność." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2018. http://dlibra.utp.edu.pl/Content/1229.
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Zasadnicznym celem przeprowadzonych badań była ocena skuteczności wykorzystania danych z okresowej kontroli użytkowości mlecznej w typowaniu krów z zaburzeniami metabolizmu energetycznego i wpływie opóżnienia u nich terminu pierwszej inseminacji na wskaźniki rozrodcze stada<br>The aim of the research was to assess the effectiveness of the use of data from periodic control of dairy utility in the selection of cows with energy metabolism disturbances and the impact of their delay in the first insemination on the reproductive indicators of the herd
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Valor, Ivars Teresa. "The effects of prescribed burning on the vigour of Mediterranean pine species." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/664281.
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La crema prescrita consisteix en l’ús planificat del foc en condicions ambientals adequades per tal d’aconseguir objectius de gestió prèviament definits. S’executa amb l’objectiu de reduir el risc d’incendis tot i que també s’utilitza per a la gestió de pastures i la conservació de la biodiversitat. La crema sota arbrat pot reduir el risc d’incendi de capçades, però també pot afectar el metabolisme primari i secundari de l’arbre. Tanmateix, les cremes haurien de minimitzar els efectes negatius del foc als arbres i maximitzar els positius. Així doncs, és important comprendre de quina manera els components específics del règim de foc, com són la intensitat del foc, severitat i estació de crema, afecten el funcionament de l’arbre. L’objectiu d’aquesta tesi és comprendre la influència que els factors del règim de cremes prescrites tenen en el metabolisme primari i secundari de tres espècies de pi amb tolerància al foc contrastada: Pinus nigra ssp. salzmannii (Dunal) Franco, P. sylvestris L. i P. halepensis Mill., utilitzant una combinació de tècniques dendrocronològiques, isotòpiques i de quantificació terpènica.
El creixement post-crema va dependre del temps transcorregut des de la crema, l’espècie, la resistència de l’arbre, la severitat del foc i del creixement de l’arbre abans de la crema. L’any de la crema, el creixement es va reduir en P. halepensis i no es va veure afectat en P. nigra i P. sylvestris. Amb el pas del temps, el creixement es va incrementar en P. nigra, es va recuperar en P. halepensis i es va reduir en P. sylvestris. La probabilitat de morir va ser menor en P. nigra que en P. sylvestris. L’estació de crema va emergir com un factor important per explicar la mortalitat inicial: la probabilitat que un pi mori és més alta a la primavera que a la tardor per a un cert nivell de capçada socarrimada. La mortalitat tardana va ser més alta a les cremes de tardor que a les de primavera degut als majors temps de combustió registrats a la base dels troncs.
Una reducció rellevant de la competència arbrada va augmentar significativament el creixement mitjançant un efecte positiu en la fusta de tardor de P. nigra i P. sylvestris, a mesura que el dany causat pel foc a la tija va disminuir. A més, vam demostrar que una crema executada just després d’un any sec no redueix la resiliència dels pins en comparació amb la dels pins no cremats. En P. halepensis, una reducció significativa de la competència va resultar en majors creixements amb el pas del temps, especialment en pins amb un menor volum de capçada socarrimada. Aquest augment va coincidir amb un any sec i es va associar amb una major conductància estomàtica, el que suggereix que la disponibilitat d’aigua va millorar després de la crema. La crema també va afectar al metabolisme secundari, específicament a la quantitat i al tipus de terpens segons l’espècie de pi i la severitat. A major volum de capçada socarrimada, la concentració de terpens a l’acícula dels pins 24 h post-crema fou major, però 1 any després es va produir una notable disminució. Aquesta reducció va ser més pronunciada en pins beneficiats per l’augment de la disponibilitat de recursos després de la crema, el que suggereix que els productes assimilats pels pins es van assignar al creixement en lloc de a mecanismes de defensa.
Aquesta tesi proporciona informació valuosa per ajudar en la millora de la planificació de les cremes als boscos de pi mediterranis, en termes d’intensitat, severitat i estació de crema, oferint una nova finestra d’oportunitat per a l’ús de la crema prescrita com a eina de gestió forestal.<br>Prescribed burning is the planned use of fire to meet clear management objectives under suitable environmental conditions. It is usually executed to reduce fire hazard, but also to manage range and conserve biodiversity. Prescribed burning applied under a forest canopy can reduce crown fire hazard; however, underburning might affect the primary and secondary metabolism of trees. Planning underburning to reduced fire hazard, while minimizing the negative effects and maximizing the positive effects on trees, requires understanding how specific components of the fire regime, such as fire intensity, severity and season, affect tree performance. The goal of this doctoral thesis is to understand the influence of prescribed burning regime factors and related fire impacts on the primary and secondary metabolisms of three pine species with contrasting fire tolerances: Pinus nigra ssp. salzmannii (Dunal) Franco, P. sylvestris L. and P. halepensis Mill., using a combination of dendrochronological, isotope and terpene quantification techniques.
Post-burning growth variations depended on the time since burning, the pine species, tree resistance, fire severity and tree performance before burning. In the year of burning, growth was reduced in P. halepensis and unaffected in P. nigra and P. sylvestris. However, as time passed, growth increased in P. nigra, recovered in P. halepensis and decreased in P. sylvestris. P. nigra had a lower probability of dying than P. sylvestris. Burning season emerged as an important factor for explaining initial post-burning pine mortality, since for a certain level of crown injury the probability of a pine dying was higher in spring than in fall. In contrast, delayed pine mortality was higher in fall than in spring burns probably due to the longer combustion times recorded during the fall burns at the base of the trunk.
A relevant release of tree competition increased growth through a positive effect on the latewood of P. nigra and P. sylvestris as stem injury decreased. Moreover, we showed that burning just after a dry year did not reduce the growth resilience of pines in comparison with unburned pines. In P. halepensis a relevant competition release, especially in pines with lower crown volume scorched, resulted in higher growth rates as time since burning increased. This growth response coincided with a dry year and was associated with higher stomatal conductance, suggesting that water availability was enhanced after burning. Burning also affected the secondary metabolism of pines, and specifically the amount and type of terpene production depending on the pine species and fire severity. Thus, as crown injury increased, needle terpene concentration 24h post-burning also augmented. However, a remarkable decrease occurred at one year post-burning. This reduction was more pronounced in pines benefited by the increase in resource availability after burning, suggesting that pines were allocating assimilates to growth rather than to defence.
From a fuel management point of view, this thesis provides valuable information that can be used to better plan prescribed burning in Mediterranean Pinus forests, in terms of required fire intensity, severity and burning season, offering a new window of opportunity for the use of prescribed burning as a forest management tool.
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Treitinger, Aricio. "Alterações metabólicas e do sistema de defesa antioxidante no plasma e em células mononucleares decorrentes da infecção pelo vírus da imunodeficiência humana." Universidade de São Paulo, 1996. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-10032015-110940/.
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No presente trabalho analisou-se um total de 101 indivíduos, sendo 26 não infectados e 75 infectados pelo HIV e classificados de acordo com o Walter Reed Army Institute (28 pacientes WR 1, 31 pacientes WR 2 e 16 pacientes WR 3/4). 05 indivíduos infectados pelo HIV apresentaram, nos estágios iniciais, uma diminuição progressiva do peso corporal, dos níveis séricos de uréia, albumina, colesterol total, HOL colesterol e LOL colesterol. Já os níveis séricos de proteínas totais, globulinas, IgG, IgA, α1 glicoproteína ácida, haptoglobina e as atividades enzimáticas da AST e da LD apresentaram elevação nos indivíduos infectados e em conseqüência da evolução da infecção. Os triglicérides demonstraram apenas tendência para aumento dos níveis séricos nos indivíduos estadiados como WR3/4. Os níveis de ferro sérico encontraram-se diminuídos nos indivíduos estadiados como WR 3/4, enquanto que a concentração de transferrina apresentou-se diminuída apenas no Grupo WR 2. Houve uma tendência para a elevação progressiva dos níveis médios de ferritina com a evolução da doença. Nenhuma alteração foi verificada nos níveis de proteína \"C\" reativa. A EC-SOO apresentou diminuição dos níveis de atividade nos indivíduos infectados pelo HIV, enquanto que em células mononucleares a SOD apresentou atividade diminuída nos indivíduos estadiados como WR 3/4. A GSH-Px não apresentou alteração de sua atividade em decorrência da infecção pelo HIV. Os níveis plasmáticos do α-tocoferol e do ascorbato apresentaram tendência para diminuição, enquanto o β-caroteno não apresentou alteração nos grupos estudados. Estes resultados sugerem que a haptoglobina, as globulinas e a IgA podem ser utilizadas para a avaliação da evolução da infecção pelo HIV. Por outro lado, os níveis dos constituintes do sistema de defesa antioxidante analisados indicam que os indivíduos soropositivos encontram-se menos protegidos contra a ação de espécies reativas de oxigênio, o que favoreceria a presença de um estresse oxidativo e a replicação viral.<br>A total number of 101 individuals, including 26 controls and 75 patients classified according to the Walter Reed Army Institute (28 WR 1, 31 WR 2 and 16 WR 3/4) was studied. HIV infected individuals presented, during the early stages, a progressive reduction of body weigth, as well as urea, albumin, total cholesterol, HDL cholesterol and LDL cholesterol in blood serum. However, increased serum levels of total protein, globulin, IgG, IgA, α1 acid glycoprotein, haptoglobin, AST and LD were observed in HIV infected individuals during the evolution of infection. Decreased serum iron and a trend for increasing triglyceride was shown only for those individuals classified as WR 3/4. Transferrin was diminished only in the WR 2 group. A trend for enhancing serum ferritin following the progession of HIV infection was also observed. No alteration was observed on the levels of reactive \"C\" protein. Decreased EC-SOD activities were observed in HIV infected individuals as compared to controls, whereas in mononuclear cells the SOD activity was diminished only in WR 3/4 patients. HIV infection did not alter GSH-Px activity. A trend for decreasing α-tocopherol and ascorbate plasma levels was shown during the evolution of HIV infected patients, while no difference was observed for β-carotene levels in the studied groups. The above results suggest that haptoglobin, globulins and IgA can be used to assess the evolution of the HIV infection. Moreover, the decreased levels of the antioxidant defense system components observed in HIV infected patients may indicate that they are under an oxidative stress that could favor HIV replication.
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Mc, Grail Fernández Kimberley Anne. "Targeting NRAS mutant melanomas through metabolic stress." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/673108.
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Al melanoma cutani, els gens que presenten una major incidència mutacional són els gens BRAF i NRAS. Alteracions en aquests gens resulten en l'activació constitutiva de la via de RAS-ERK1/2, contribuint activament així en el desenvolupament i la progressió tumoral del melanoma. Tot i que ambdues mutacions donen lloc a alteracions de la mateixa via de senyalització, està àmpliament descrit que els tumors que es generen d’aquestes constitueixen dues entitats diferents tant a nivell molecular com des del punt de vista de la clínica. Una qüestió rellevant al voltant rau en el fet que mentre els melanomes mutats en BRAF disposen de teràpies específiques dirigides contra aquest oncogèn, els melanomes que presenten mutacions en NRAS no tenen tractaments específics. Com a conseqüència, aquests pacients són tractats amb teràpies antitumorals més genèriques, amb taxes de resposta molt menors i a més amb una elevada toxicitat. En aquest context, desemmascar les diferències moleculars existents entre els tumors amb mutacions en BRAF i en NRAS és essencial per a l'establiment de noves estratègies terapèutiques dirigides a pacients que presenten mutacions en NRAS.
Resultats obtinguts amb anterioritat al nostre grup de recerca, juntament amb els d'altres investigacions, han confirmat la presència de diferents patrons metabòlics subjectes a la regulació per BRAFV600E. No obstant això, gairebé no existeix evidència al voltant del paper de les mutacions en NRAS a la regulació metabòlica. L'establiment de característiques metabòliques específiques de melanomes amb mutacions en NRAS podria contribuir al desenvolupament de nous enfocaments terapèutics dirigits contra aquest tipus de tumor.
Durant el desenvolupament d'aquest estudi hem investigat les implicacions moleculars derivades de la manca de glucosa en cèl·lules de melanoma mutades en NRASQ61 i BRAFV600E, per tal d'establir si la presència de característiques metabòliques depenent de NRAS podria ser explotada per al desenvolupament de noves teràpies contra aquest tipus de tumor. En aquest estudi, hem demostrat la presència de patrons metabòlics sota el control d'NRASQ61. Les cèl·lules que presenten mutacions en NRASQ61 mostren una resposta diferencial a l'estrès metabòlic en comparació amb les cèl·lules mutades en BRAFV600E, donant com a resultat la hiperactivació de la via de RAS-ERK1/2 i a la sensibilització d'aquestes cèl·lules a l'inhibidor multi-cinasa Sorafenib. PFKFB2, PFKFB3 i PFK-1 són elements clau en la regulació d'aquest procés. Amb això, proposem una nova aproximació terapèutica per al tractament dirigit dels melanomes mutats en NRASQ61, establerta per la combinació de 2-deoxi-D-glucosa (2DG) i Sorafenib. Després dels resultats obtinguts, podem concloure que els tumors que presenten mutacions en NRAS i BRAF són entitats diferents a diferents nivells, no només a nivell clínic i molecular, sinó també a nivell metabòlic, el que implica l'existència de noves finestres terapèutiques per al tractament de tumors que presenten mutacions en NRAS.<br>Los genes BRAF y NRAS presentan una mayor incidencia mutacional en melanoma cutáneo. Alteraciones en estos genes resultan en la activación constitutiva de la vía de RAS-ERK1/2, lo que contribuye activamente al desarrollo y la progresión tumoral del melanoma. Aunque ambas mutaciones dan lugar a alteraciones de la misma vía de señalización, ha sido ampliamente descrito que los tumores que se generan de las mismas, constituyen dos entidades diferentes tanto a nivel molecular como desde el punto de vista clínico. Una cuestión relevante reside en el hecho de que mientras los melanomas mutados en BRAF disponen de terapias específicas dirigidas contra el oncogén, los melanomas que presentan mutaciones en NRAS carecen de tratamientos específicos. Como consecuencia, estos pacientes son tratados con tratamientos antitumorales más genéricos, que desembocan en tasas de respuesta mucho menores y en una elevada toxicidad. En este contexto, el desenmascaramiento de las diferencias moleculares existentes entre los tumores con mutaciones en BRAF y en NRAS es esencial para el establecimiento de nuevas estrategias terapéuticas dirigidas a pacientes que presentan mutaciones en NRAS.
Resultados obtenidos previamente en nuestro grupo de investigación, sumados a los de otras investigaciones, han confirmado la presencia de diferentes patrones metabólicos sujetos a la regulación por BRAFV600E. Sin embargo, apenas existe evidencia sobre el papel de las mutaciones en NRAS en la regulación metabólica. El establecimiento de características metabólicas específicas de melanomas con mutaciones en NRAS podría contribuir al desarrollo de nuevos enfoques terapéuticos dirigidos contra este tipo de tumor.
Durante el desarrollo de este estudio hemos investigado las implicaciones moleculares derivadas de la falta de glucosa en células de melanoma mutadas en NRASQ61 y BRAFV600E, con el fin de establecer si la presencia de características metabólicas dependientes de NRAS podría ser explotada para el desarrollo de nuevas terapias contra este tipo de tumor. En este estudio, hemos demostrado la presencia de patrones metabólicos bajo el control de NRASQ61. Las células que presentan mutaciones en NRASQ61 muestran una respuesta diferencial al estrés metabólico, en comparación con las células mutadas en BRAFV600E, que desemboca en la hiperactivación de la vía de RAS-ERK1/2 y en la sensibilización de estas células al inhibidor multi-quinasa Sorafenib. PFKFB2, PFKFB3 y PFK-1 son elementos clave en la regulación de este proceso. Adicionalmente, proponemos una nueva aproximación terapéutica para el tratamiento dirigido de los melanomas mutados en NRASQ61, basada en la combinación de 2-deoxi-D-glucosa (2DG) y Sorafenib. Tras los resultados obtenidos, podemos concluir que los tumores que presentan mutaciones en NRAS y BRAF son entidades diferentes a distintos niveles, no solo a nivel clínico y molecular, sino también a nivel metabólico, lo que implica la existencia de nuevas ventanas terapéuticas para el tratamiento de tumores que presentan mutaciones en NRAS.<br>BRAF and NRAS are the most commonly found mutated genes in cutaneous melanoma. Alterations in these genes result in the constitutive activation of the RAS-ERK1/2 pathway, contributing to tumor development and progression. Beside both genes are consecutive located in the same signaling cascade, BRAF and NRAS mutated tumors are considered two different entities at clinical and molecular levels, resulting in distinct signaling patterns and different biological behavior. Furthermore, while there is a first line of treatment using targeted therapy against BRAF mutant melanomas, NRAS mutant tumors remain without specific line of treatment, showing low response rates and high toxicity to the currently applied therapies. Thus, the understanding of the molecular differences between BRAF and NRAS mutant tumors is essential to improve therapeutic opportunities for the treatment of patients carrying NRAS mutations.
Previous results in our group, together with additional investigations, have highlighted the presence of different metabolic settings subjected to BRAFV600E oncogene regulation. However, little is known about the role of NRAS mutations in metabolic rewiring. Deciphering metabolic settings in NRAS mutant melanomas could provide new avenues for the establishment of specific therapeutic approaches against these, until now, untargetable tumors.
In this study, we have investigated the molecular implications of glucose starvation in NRASQ61 and BRAFV600E mutant cells in order to establish whether the presence of NRAS-dependent metabolic settings can be exploited for the development of targeted therapies against NRAS mutant melanomas. Overall, in this study we have demonstrated the presence of NRASQ61 oncogene-dependent metabolic settings. NRASQ61 mutant cells show a differential response to metabolic stress when compared to BRAFV600E mutant cells, which results in the hyperactivation of the RAS-ERK1/2 pathway and the sensitization to the multikinase inhibitor Sorafenib. PFKFB2, PFKFB3 and PFK-1 are key players in the regulation of this process. We also propose a novel approach for the specific targeting of NRASQ61 mutant melanomas based on the combination of 2-deoxy-D-glucose (2DG) and Sorafenib. We conclude that NRAS and BRAF mutant tumors are different entities at different levels, not only at molecular and clinical levels but also at metabolic level and this fact provides a new therapeutic window for the targeting of NRAS mutant tumors.<br>Universitat Autònoma de Barcelona. Programa de Doctorat en Bioquímica, Biologia Molecular i Biomedicina
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Mota, Martorell Natàlia. "Oxidative stress homeostasis and longevity in mammals." Doctoral thesis, Universitat de Lleida, 2021. http://hdl.handle.net/10803/672775.
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Les espècies més longeves han evolucionat disminuint la producció endògena d’espècies reactives d’oxigen i proveint-se d’estructures resistents a la oxidació. Per tant, aquelles espècies que viuen més gaudeixen de mitocòndries metabòlicament més eficients i estructuralment més estables. De fet, característiques fenotípiques de la longevitat inclouen la reducció del contingut del complex I i dels aminoàcids sulfurats. Aleshores, l’activitat de determinades vies de senyalització intracel·lulars juga un paper clau regulant l’expressió de gens associats a un fenotip longeu.
En aquest context, aquesta tesi pretén determinar i) la modulació de determinades subunitats del complex I associada a la longevitat; ii) els canvis en el contingut dels aminoàcids sulfurats i els seus intermediaris metabòlics en teixits post-mitòtics i iii) plasma d’espècies més longeves; iv) la regulació del contingut dels diferents elements específics del complex 1 de mTOR en termes de longevitat; i v) l’existència un perfil metabòlic associat a humans de longevitat extrema.
Els resultats obtinguts mostren l’existència de perfils metabòlics associats a la longevitat de les espècies que, en alguns casos, són diferents a aquells perfils associats a la longevitat individual. A més, les espècies més longeves han evolucionat disminuint el contingut de determinades subunitats del complex I que podrien ésser responsables de la menor producció d’espècies reactives d’oxigen. Per altra banda, existeixen factors genètics que podrien determinar l’activitat basal de mTORC1, i que podrien, almenys en part, explicar el fenotip associat a la longevitat. Per tant, sembla que l’assoliment d’una major longevitat implica una adaptació metabòlica i estructural.<br>Las especies más longevas han evolucionado disminuyendo la producción endógena de especies reactivas de oxígeno y proveyéndose de estructuras resistentes a la oxidación. Por lo tanto, aquellas especies que viven más disfrutan de mitocondrias metabólicamente más eficientes y estructuralmente más estables. De hecho, características fenotípicas de la longevidad incluyen la reducción del contenido del complejo I y de amino ácidos sulfurados. Por lo tanto, la activad de determinadas vías de señalización intracelular juegan un papel clave regulando la expresión de genes asociados a un fenotipo longevo.
En este contexto, esta tesis pretende determinar i) la modulación de determinadas subunidades del complejo I asociada a la longevidad; ii) los cambios en el contenido de amino acido sulfurados y de sus intermediarios metabólicos en tejidos post-mitóticos y iii) plasma de especies más longevas; iv) la regulación del contenido de distintos elementos específicos del complejo 1 de mTOR en términos de longevidad; y v) la existencia de un perfil metabólico asociado a humanos de longevidad extrema.
Los resultados obtenidos muestran la existencia de perfiles metabólicos asociados a la longevidad de las especies que, en algunos casos, son diferentes a aquellos perfiles asociados a la longevidad individual. Además, las especies más longevas han evolucionado disminuyendo el contenido de determinadas subunidades del complejo I que podrían ser responsables de la menor producción de especies reactivas de oxígeno. Por otra parte, existen factores genéticos que podrían determinar la actividad basal de mTOR, y que podrían, al menos en parte, explicar el fenotipo asociado a la longevidad. Por lo tanto, parece que lograr una mayor longevidad implica una adaptación metabólica y estructural.<br>Long-lived species have evolved by decreasing the rate of endogenous reactive oxygen species production and providing them of oxidation-resistant structures. Hence, species that live longer benefit from metabolically efficient and structurally stable mitochondria. In fact, phenotypic traits of longevity include reduced content of complex I and sulphur-containing amino acids. Then, the activity of selected intracellular signalling pathways plays a key role regulating the expression of genes associated to a longevity phenotype.
In this context, this thesis aims to determine i) the modulation of specific complex I subunits associated to longevity; ii) the changes on sulphur amino acids content and its metabolic intermediates in post-mitotic tissues and ii) plasma from long-lived species; iv) the content regulation of the different mTOR complex 1 specific forming elements in terms of longevity; and v) the existence of a metabolic profile associated to human extreme longevity.
The obtained results reveal the existence of metabolic profiles associated to species longevity that, in some cases, differ from those profile associated to individual longevity. Furthermore, longer lived species have evolved reducing the content of specific complex 1 subunits that might be responsible for the limited reactive oxygen species production. Otherwise, genetic factors that might determine the basal activity of mTORC1 exist, and that could, at least In part, explain the longevity associated phenotype. Thus, it seems that the achievement of an extended longevity implies a metabolic and structural adaptation.
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Aarts, Michelle M. "Metabolism and immune effects of sulfamethoxazole and hydroxylamine metabolite." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21080.pdf.
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Jorge, Letícia Galhardo. "Desempenho fotossintético, perfil e atividade do óleo essencial de Xylopia aromatica (Lam.) Mart. nas fases vegetativa e reprodutiva no cerrado paulista." Botucatu, 2020. http://hdl.handle.net/11449/192182.
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Orientador: Carmen Silvia Fernandes Boaro<br>Resumo: Espécies vegetais são capazes de produzir diversidade de substâncias, que desempenham funções importantes para sua sobrevivência e adaptação ao ecossistema. O metabolismo primário, é essencial para o crescimento, desenvolvimento, maturação e reprodução de qualquer espécie. O metabolismo especializado, dependente do primário, é responsável por originar o óleo essencial, que são misturas de metabólitos especializados voláteis, representados principalmente por monoterpenos e sesquiterpenos. Cada espécie vegetal produz um óleo essencial de composição característica específica, podendo ser influenciado por fatores bióticos e abióticos. A fenologia pode influenciar processos bioquímicos e rotas metabólicas capazes de modificar a formação de substâncias biologicamente ativas, alterando diretamente o conteúdo e a qualidade dos óleos essenciais. Sendo assim, o objetivo deste trabalho foi avaliar se as fases fenológicas, vegetativa e reprodutiva modificam o desempenho fotossintético e o perfil do óleo essencial de Xylopia aromatica (Lam.) Mart., influenciando sua atividade biológica na defesa antioxidante e ação antifúngica. As variáveis, fluorescência da clorofila a, trocas gasosas, carboidratos, atividade enzimática e peroxidação lipídica, potencial água, conteúdo relativo de água das folhas, extração, rendimento, caracterização química e atividade antifúngica do óleo essencial de Xylopia aromatica foram avaliadas em 24 plantas, 12 no estádio vegetativo e 12 no reprodutivo, coletadas... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: Research aimed at the knowledge of plant species allows the elaboration of projects that aim at the understanding of development, conservation of biodiversity and sustainable exploitation of natural resources. The primary metabolism, represented by photosynthesis and the specialized one, that synthesizes the essential oil, can be influenced by the environmental and phenological conditions, which can influence the chemical profile of the essential oil and the biological activity in the vegetal defense, including against fungi, bacteria and virus. Compounds from the specialized metabolism present biological activity and potential for the production of bactericides and fungicides. Therefore, it is necessary to know the stage of development of plant species in which the substances of interest, with economic potential, are more concentrated, thus orienting, if appropriate, the collection period, aiming at the conservation and sustainable use. There are scientific studies that reveal biological activity of essential oils, as observed for the genus Xylopia, but none of them relates the primary and specialized metabolism to the stage of development in which the species is found. In this way, the objective of this research was to evaluate if the phenological, vegetative and reproductive phases of Xylopia aromatica (Lam.) Mart. modify the photosynthetic performance and the profile of the essential oil, which may influence its biological activity in the antioxidant defense and antifunga... (Complete abstract click electronic access below)<br>Mestre
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Vidal, Alabró Anna. "Estudi de l’activació de la glucocinasa (GKA456V) en fetge perivenós." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/32022.
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La GK és clau en la regulació del metabolisme glucídic tant per la seva funció al pàncrees en què determina la secreció d’insulina, com per la seva funció al fetge on controla les vies d’utilització i d’emmagatzematge de glucosa. Per aquest motiu és una bona diana per a la teràpia de la diabetis, i diverses companyies farmacèutiques estan desenvolupant activadors sintètics de la GK (GKA) pel tractament de la diabetis de tipus 2.
Els estudis de GKAs existents avaluen l’activació de la GK a nivell sistèmic i no es coneixen els seus efectes específis sobre la GK al fetge. Per indagar-los, com que no disposàvem d’un GKA específic per a la GK del fetge, ens vam proposar la sobrexpressió d’una forma de GK amb una mutació activadora (GK-A456V) que confereix característiques cinètiques a l’enzim idèntiques a les obtingudes amb els GKAs. L’introduírem al fetge perivenós mitjançant transfecció gènica hidrodinàmica (perquè és la zona on s’expressa majoritàriament l’enzim salvatge en condicions fisiològiques). Un dels controls emprats en l’estudi fou la sobrexpressió de la GK salvatge també a la zona perivenosa, que ens permetria comparar els resultats d’aquesta sobrexpressió local de la GK amb la sobrexpressió no zonal descrita a la bibliografia.
Per una banda, avaluàrem els efectes de la sobrexpressió i de l’activació de la GK hepàtica en el context d’un animal sa a llarg termini, per determinar si hi havia risc de resistència a insulina (com s’esdevé en alguns models de sobrexpressió no zonal de GK al fetge). Tant l’activació com la sobrexpressió de GK al fetge perivenós a curt termini comportaren una disminució de la glicèmia i de la insulinèmia. No obstant, en avaluar-ho a llarg termini, la sobrexpressió de GK generà un fenotip de resistència a insulina exclusivament al fetge. En canvi, la GK-A456V comportà un fenotip amb un perfil metabòlic similar als animals controls, sense alteracions dels nivells de glúcids i lípids (sèrics i hepàtics). Al fetge, malgrat que no provocava canvis en el metabolisme glucídic i lipídic, l’activació de la GK va promoure la desregulació per GKRP i la inducció de la glucosa-6-fosfatasa. Per altra banda, la presència de la GK activada al fetge resultà en una activació del catabolisme al teixit adipós.
Per altra banda, vam emprar un model de diabetis de tipus 1 per determinar els efectes de la GK-A456V sobre el fenotip diabètic independentment de la insulina, amb la finalitat de valorar l’activació de la GK hepàtica com a tractament alternatiu als GKAs sistèmics. La sobrexpressió perivenosa de GK, tot i que comportà un increment del metabolisme de glucosa al fetge (increment del glicogen hepàtic, de ub-PFK-2, de L-PK, c-myc) i una disminució de la gluconeogènesi (reducció dels nivells de PEPCK), va provocar dislipidèmia com a resultat de la disminució de la β-oxidació d’àcids grassos (reducció dels nivells de Cpt-1) i una inducció de la lipogènesi hepàtica (augment de FAS, ACC, ChREBP). Altres models de sobrexpressió de GK, descrits a la literatura, que no tenien en compte el concepte de zonació hepàtica, també presentaven alteracions en el metabolisme lipídic. En canvi, l’activació de la GK comportà una rellevant disminució de la hiperglicèmia diabètica tot i tenir un lleu efecte sobre l’activació del metabolisme de glucosa i sobre la inhibició de la gluconeogènesi. Sobretot és interessant que la millora de la hiperglicèmia diabètica no va acompanyada d’alteracions del metabolisme lipídic.
En conjunt, aquest treball suggereix que l’activació de la GK exclusivament al fetge és una estratègia terapèutica millor per a la diabetis que la sobrexpressió de la GK.<br>Synthetic glucokinase activators have been used in the context of type 2 diabetes therapy, mainly for their insulin secretagogue activity. However, the impact of these drugs on liver GK has not been studied in vivo. Since GK activators and activating GK mutations confer identical kinetic properties to GK, we hypothesize that hepatic overexpression of a mutated form of GK, GKA456V, described in a patient with Persistent Hyperinsulinemic Hypoglycemia of Infancy (PHHI), shall mimic the liver-specific effects of GK-activating drugs.
GKA456V was overexpressed in the liver of streptozotocin diabetic mice and also in healthy mice. Metabolite profiling in serum and liver extracts, together with key components of glucose and lipid homeostasis, were analyzed and compared to GK wild-type transfected animals. Cell compartmentalization of mutant and wild-type GK was also examined in vivo.
In the type 1 diabetic mice, GKA456V overexpression markedly reduced blood glucose in the absence of dislipidemia, in contrast to wild-type GK-overexpressing mice. Enhanced glucose utilization did not correlate with glycogen synthesis or lactate production. PEPCK mRNA was not affected, whereas the mRNA for the catalytic subunit of glucose-6-phosphatase was upregulated ~4-fold in the liver of GKA456V treated animals. Moreover, GKA456V was not translocated to the nucleus after a short fast, confirming that this activating mutation disrupted GKRP regulation.
In healthy mice, the overexpression of hepatic GK resulted in insulin resistance. Otherwise, GKA456V overepxressing animals were not insulin resistant. They showed increased mRNA and protein content of the catalytic subunit of glucose-6-phosphatase in the liver, and an idnuction of catabolism in their adipose tissue.
Our results validate liver specific GK activation as a strategy for diabetes therapy and provide new insights into the complex GK regulatory network.
Books on the topic "Metabolism"
1
American, Chemical Society Symposium "Biosynthesis and Metabolismof Secondary-Metabolite Natural Products" (1991 Atlanta Ga ). Secondary-metabolite biosynthesis and metabolism. New York: London, 1992.
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Petroski, Richard J., and Susan P. McCormick, eds. Secondary-Metabolite Biosynthesis and Metabolism. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-3012-1.
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J, Petroski Richard, McCormick Susan P, and American Chemical Society, eds. Secondary-metabolite biosynthesis and metabolism. New York: Plenum Press, 1992.
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Jiang, Xian-Cheng, ed. Sphingolipid Metabolism and Metabolic Disease. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-0394-6.
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R, Verpoorte, and Alfermann A. W, eds. Metabolic engineering of plant secondary metabolism. Dordrecht: Kluwer Academic Publishers, 2000.
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Verpoorte, Robert, and A. W. Alfermann, eds. Metabolic Engineering of Plant Secondary Metabolism. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-015-9423-3.
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McCandless, David W., ed. Cerebral Energy Metabolism and Metabolic Encephalopathy. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-1209-3.
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1941-, McCandless David W., ed. Cerebral energy metabolism and metabolic encephalopathy. New York: Plenum Press, 1985.
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(Firm), Knovel, ed. Metabolic engineering of plant secondary metabolism. Dordrecht: Kluwer Academic Publishers, 2000.
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Verpoorte, Robert. Metabolic Engineering of Plant Secondary Metabolism. Dordrecht: Springer Netherlands, 2000.
Find full textBook chapters on the topic "Metabolism"
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Guo, Shenghao, Yanni Gu, Jiayin Qu, and Anne Le. "Bridging the Metabolic Parallels Between Neurological Diseases and Cancer." In The Heterogeneity of Cancer Metabolism, 229–48. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-65768-0_17.
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AbstractDespite the many recent breakthroughs in cancer research, oncology has traditionally been seen as a distinct field from other diseases. Recently, more attention has been paid to repurposing established therapeutic strategies and targets of other diseases towards cancer treatment, with some of these attempts generating promising outcomes [1, 2]. Recent studies using advanced metabolomics technologies [3] have shown evidence of close metabolic similarities between cancer and neurological diseases. These studies have unveiled several metabolic characteristics shared by these two categories of diseases, including metabolism of glutamine, gamma-aminobutyric acid (GABA), and N-acetyl-aspartyl-glutamate (NAAG) [4–6]. The striking metabolic overlap between cancer and neurological diseases sheds light on novel therapeutic strategies for cancer treatment. For example, 2-(phosphonomethyl) pentanedioic acid (2-PMPA), one of the glutamate carboxypeptidase II (GCP II) inhibitors that prevent the conversion of NAAG to glutamate, has been shown to suppress cancer growth [6, 7]. These promising results have led to an increased interest in integrating this metabolic overlap between cancer and neurological diseases into the study of cancer metabolism. The advantages of studying this metabolic overlap include not only drug repurposing but also translating existing knowledge from neurological diseases to the field of cancer research. This chapter discusses the specific overlapping metabolic features between cancer and neurological diseases, focusing on glutamine, GABA, and NAAG metabolisms. Understanding the interconnections between cancer and neurological diseases will guide researchers and clinicians to find more effective cancer treatments.
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Sackmann-Sala, Lucila, D. R. Bailey Miles, and John J. Kopchick. "Metabolism and Metabolic Regulation." In Laron Syndrome - From Man to Mouse, 451–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-11183-9_52.
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Verpoorte, R. "Secondary Metabolism." In Metabolic Engineering of Plant Secondary Metabolism, 1–29. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-015-9423-3_1.
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Günther, Ulrich L., Mei G. Chong, Tatiana Volpari, Katarzyna M. Koczula, Karen Atkins, Christopher M. Bunce, and Farhat L. Khanim. "Metabolic Fluxes in Cancer Metabolism." In Tumor Cell Metabolism, 315–48. Vienna: Springer Vienna, 2015. http://dx.doi.org/10.1007/978-3-7091-1824-5_14.
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Saghiv, Moran S., and Michael S. Sagiv. "Metabolism." In Basic Exercise Physiology, 33–147. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-48806-2_2.
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Davidson, Debra J. "Metabolism." In Environment and Society, 47–70. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-76415-3_3.
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Leong, Wen B., Shahrad Taheri, Anna M. Stone, and G. Neil Thomas. "Metabolism." In Encyclopedia of Behavioral Medicine, 1377–81. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-39903-0_472.
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Khanfer, Riyad, John Ryan, Howard Aizenstein, Seema Mutti, David Busse, Ilona S. Yim, J. Rick Turner, et al. "Metabolism." In Encyclopedia of Behavioral Medicine, 1231–35. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4419-1005-9_472.
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Cárdenas, María Luz, and Athel Cornish-Bowden. "Metabolism." In Encyclopedia of Astrobiology, 1–3. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_963-2.
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Kooyman, Gerald L. "Metabolism." In Zoophysiology, 119–28. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83602-2_10.
Full textConference papers on the topic "Metabolism"
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Amaya, Hisashi, and Hideaki Miyuki. "Laboratory Reproduction of Potential Ennoblement of Stainless Steels in Natural Seawater." In CORROSION 1999, 1–15. NACE International, 1999. https://doi.org/10.5006/c1999-99168.
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Abstract The localized corrosion susceptibility of stainless steels, such as type 316L, immersed in natural seawater is higher than those in synthetic seawater. It is widely observed that the corrosion potential of stainless steels in natural seawater becomes noble over +0.3V vs SCE. This phenomenon is caused by the influence of the microorganisms in the natural seawater, and therefore it is considered as Microbially Influenced Corrosion (MIC). In this paper, the laboratory reproduction of the corrosion potential ennoblement was examined on the basis of the metabolize of aerobic bacteria (pH, dissolved oxygen and metabolite). The electrochemical measurements in natural seawater and synthetic seawater with bacterial mediums were carried out. The corrosion potential of stainless steels became noble in only natural seawater, and cathodic current density increased around corrosion potential, these results suggest that the presence of oxidizer on the metal surface which has higher redox potential than that of oxygen. As the corrosion potential became noble during the logarithmic phase of bacterial growth in the result of the examination with isolated bacteria, it is suggested that the aerobic metabolism of bacteria effects the ennoblement of corrosion potential. The ennoblement was also reproduced in laboratory by the addition of oxidase simulated the metabolism of aerobic bacteria. The oxidase produced the peroxide by the reduction of oxygen which has higher redox potential than that of oxygen, therefore it is considered that the corrosion potential ennoblement is caused by the peroxide generated by the metabolism of aerobic bacteria included in the biofilm formed on the surface of the stainless steels in natural seawater.
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Rogers, Hannah, and Adam Bencard. "Metabolism and Art." In 28th International Symposium on Electronic Art. Paris: Ecole des arts decoratifs - PSL, 2024. http://dx.doi.org/10.69564/isea2023-25-short-rogers-et-al-metabolism-and-art.
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SHORT PAPER. Metabolic arts should be added to the emerging interdiscipline of metabolic humanities and this paper will discuss ways of defining metabolism that might be productive in helping to produce tools and touchstones for metabolic readings of contemporary art before presenting examples of artworks which might be interestingly illuminated by light of this sign, taking time to relish the process of these materially oriented internal analysis coupled with how the work might be considered in terms of its broader implications for the concept of metabolism.
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Amaral, Cisnara Pires, Eduarda Pires Amaral, and Cézane Priscila Reuter. "Cellular metabolism, genetics and lifestyle." In VI Seven International Multidisciplinary Congress. Seven Congress, 2024. http://dx.doi.org/10.56238/sevenvimulti2024-107.
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The text addresses the intersection between metabolism, DNA and nutrition in contemporary life, highlighting how these topics are widely discussed and associated by the beauty and health industry. Concerns about aging and cellular maintenance have become central, driving research and practices that aim to understand and influence metabolic and genetic processes. The discussion emphasizes the importance of lifestyle in modifying genes and promoting a healthy life.
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El-fadl, Rihab, Nasser Rizk, Amena Fadel, and Abdelrahman El Gamal. "The Profile of Hepatic Gene Expression of Glucose Metabolism in Mice on High Fat Diet." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0213.
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Obesity is a growing problem worldwide, and recent data indicated that 20% of the populations would be obese. Obesity arises as a multifactorial disease caused by inherited traits that interact with lifestyle factors such as diet and physical activity. The liver plays an essential role in the gluco-regulation via regulating glucose, lipid and protein metabolism. The process of glucose metabolism is controlled by a range of molecular mechanisms and genes which affect the metabolism of the liver during intake of high fat diet (HFD). The objective of this research is to investigate the profile of hepatic gene expression of glucose metabolism in mice on HFD treated with leptin (5 mg/kg BW Ip injection). Ten wild type CD1 mice fed on HFD is used for this study, where groups are control (vehicle - leptin) and test group (vehicle + leptin). Body weight (BW) was measured, and blood chemistry, insulin and leptin were measured at the end of the experiments. Total RNA was isolated from the liver tissue, and RTPCR profiler array technology was used to evaluate the mRNA expression of 84 essential genes of hepatic glucose metabolism. The data of the BW and blood chemistry are not significantly different between the two groups. Leptin treatment enhanced the metabolic pathways and the candidate genes of the different metabolic pathway; glycogen metabolism such as Gys1, Gys2 and Pygm, pentose phosphate shunt such as Rpia and suppressed the glycolysis such as Aldob, and TCA cycle such as Mdh1b. In conclusion, this study has shown that leptin could affect the profile of the hepatic mouse genes of glucose metabolism in the early stages of HFD to induce obesity
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Dorokhina, Yu A., and G. F. Ryzhkova. "Morphological and biochemical parameters of blood in rabbits when using energymetabolic compositions." In SPbVetScience. FSBEI HE St. Petersburg SUVM, 2023. http://dx.doi.org/10.52419/3006-2022-7-18-23.
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Modern animal husbandry can no longer be imagined without special biologically active additives and a variety of protein, vitamin and mineral complexes. Among all additives, a special place is occupied by energy-metabolic compositions that give animals all the most necessary and important substances. The composition of the EC includes: yantaric acid is a universal intracellular metabolite, widely involved in metabolic reactions in the body; citric acid is the main intermediate product of the metabolic cycle of tricarboxylic acids, plays an important role in the system of biochemical reactions of cellular respiration of living organisms; iodinol – uniquea fecal medicinal substance, it determines high biological activity, regulates immunity and metabolism in the body; cyanocoalamin (vitamin B12) - prevents the appearance of anemia, enhances immunity, plays an important role in regulating the function of hematopoietic organs; glycerin has antiseptic and preservative properties.
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Kisljakova, A. A. "ASSESSMENT OF INDICATORS OF METABOLIC DISORDERS IN WORKERS OCCUPATIONALLY EXPOSED BY POWER FREQUENCY ELECTRIC AND MAGNETIC FIELDS." In The 4th «OCCUPATION and HEALTH» International Youth Forum (OHIYF-2022). FSBSI «IRIOH», 2022. http://dx.doi.org/10.31089/978-5-6042929-6-9-2022-1-110-114.
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Study is directed to power frequency (PF) electric and magnetic field (EF and PF) occupational exposure possible effects to carbohydrate and lipid metabolism. As part of the periodic medical examination based in the FSBI «Izmerov Research Institute of Occupational Health», 144 men occupationally exposed by PF electromagnetic field (EMF) were examined. The control group consisted of 40 practically healthy men who were not in contact with the studied harmful factor. Based on the results of therapeutic examination and the results of a biochemical blood test, a metabolic syndrome (MS) was established in some of the persons. It was revealed that 55.5% of the employees of the main group have MS, more than 80% of men have a violation of lipid metabolism, and 43% of the subjects - carbohydrate metabolism. Higher indicators of carbohydrate metabolism were revealed in the group of primary exposure PF EMF magnetic component. Only. The group of primary exposure to both components of PF EMF (EF and MF) had higher levels of lipid metabolism. Obtained results indicate a negative effect of PF EMF occupational exposure to lipid and carbohydrate metabolism.
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Machado, Luiza, Camila Santos, Bianca Leonardi, Andréia Rocha, Igor Fontana, Bruna Bellaver, Gianina Venturin, et al. "ACUTE PERIPHERAL INFLAMMATION IMPACT ON CEREBRAL GLUCOSE METABOLISM." In XIII Meeting of Researchers on Alzheimer's Disease and Related Disorders. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1980-5764.rpda072.
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Background: Neuroinflammation is a phenomenon already described in Alzheimer’s disease (AD). However, the effect of peripheral inflammation in AD is less understood. We recently demonstrated that severe sepsis causes acute brain metabolic disturbances. Nevertheless, whether mild acute peripheral inflammation affects brain metabolism remains unclear. Objective: We aimed at investigating the impact of mild acute peritonitis on glucose brain metabolism. Methods: Adult male wistar rats (n=6, per group) received a single intraperitoneal injection of 500 ml of carrageenan (CG, 500 µg of carrageenan i.p.) or saline (CO). Brain glucose metabolism was assessed using (18F) FDG-PET 4h after i.p. injections, which represents the first peak of inflammation. The peripheral inflammatory process was evaluated by analyzing the peritoneal lavage in a flow cytometer 48h after the injections, during the second peak of inflammation. Results: The CG animals presented a 5-fold increase in macrophages numbers (p0,05). However, carrageenan-induced inflammation did not cause acute changes in brain glucose metabolism (p>0,05). Conclusion: Mild acute peripheral inflammation does not change brain glucose metabolism. Further evaluations aiming to investigate long-term consequences of sustained mild inflammation are needed.
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Hassenkam, Tue, Ester Tsai, Henning Osholm, Kim Dalby, David Mackenzie, Mirko Holler, Dario Ferreira, Daniel Grolimund, Stephan Bruns, and Minik T. Rosing. "Eoarchean Iron Metabolism?" In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.973.
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Occhipinti, Annalisa, and Claudio Angione. "A Computational Model of Cancer Metabolism for Personalised Medicine." In Building Bridges in Medical Science 2021. Cambridge Medicine Journal, 2021. http://dx.doi.org/10.7244/cmj.2021.03.001.3.
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Cancer cells must rewrite their ‘‘internal code’’ to satisfy the demand for growth and proliferation. Such changes are driven by a combination of genetic (e.g., genes’ mutations) and non-genetic factors (e.g., tumour microenvironment) that result in an alteration of cellular metabolism. For this reason, understanding the metabolic and genomic changes of a cancer cell can provide useful insight on cancer progression and survival outcomes. In our work, we present a computational framework that uses patient-specific data to investigate cancer metabolism and provide personalised survival predictions and cancer development outcomes. The proposed model integrates patient-specific multi-omics data (i.e., genomic, metabolomic and clinical data) into a metabolic model of cancer to produce a list of metabolic reactions affecting cancer progression. Quantitative and predictive analysis, through survival analysis and machine learning techniques, is then performed on the list of selected reactions. Since our model performs an analysis of patient-specific data, the outcome of our pipeline provides a personalised prediction of survival outcome and cancer development based on a subset of identified multi-omics features (genomic, metabolomic and clinical data). In particular, our work aims to develop a computational pipeline for clinicians that relates the omic profile of each patient to their survival probability, based on a combination of machine learning and metabolic modelling techniques. The model provides patient-specific predictions on cancer development and survival outcomes towards the development of personalised medicine.
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Krupin, Evgeniy. "METABOLISM IN DOGS AND WAYS TO PREVENT ITS DISORDERS: A BRIEF REVIEW." In XIV All-Russian Scientific and Practical Conference of Young Scientists “Achievements and Prospects of Development of the Agroindustrial Complex of Russia” with international participation, dedicated to the 300th anniversary of the Russian Academy of Sciences., 141–43. TRIA FRC Kazan Scientific Center of RAS, 2024. https://doi.org/10.37071/conferencearticle_67337e410aaa31.57079936.
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The article presents a review of scientific results obtained by various scientists investigating metabolism in domestic and service dogs, possible disorders and their diagnostic markers, ways of prevention of metabolic disorders
Reports on the topic "Metabolism"
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Corscadden, Louise, and Anjali Singh. Metabolism And Measurable Metabolic Parameters. ConductScience, December 2022. http://dx.doi.org/10.55157/me20221213.
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Metabolism is the sum of chemical reactions involved in sustaining the life of organisms.[1] It constantly provides your body with the energy to perform essential functions. The process is categorized into two groups:[2] Catabolism: It’s the process of breaking down molecules to obtain energy. For example, converting glucose to pyruvate by cellular respiration. Anabolism: It’s the process of synthesis of compounds required to run the metabolic process of the organisms. For example, carbohydrates, proteins, lipids, and nucleic acids.[2] Metabolism is affected by a range of factors, such as age, sex, muscle mass, body size, and physical activity affect metabolism or BMR (the basal metabolic rate). By definition, BMR is the minimum amount of calories your body requires to function at rest.[2] Now, you have a rough idea about the concept. But, you might wonder why you need to study it. What and how metabolic parameters are measured to determine the metabolism of the organism? Find the answer to all these questions in this article.
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Popov, V. S., N. V. Vorobeva, and G. A. Svazlian. The relationship of energy metabolism and metabolism in pigs. Вестник Курской государственной сельскохозяйственной академии, 2019. http://dx.doi.org/10.18411/issn1997-0749.2019-03-74-79.
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Glaser, M. Cellular energy metabolism. Office of Scientific and Technical Information (OSTI), June 1991. http://dx.doi.org/10.2172/5714213.
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Kokurina, Olga Yu. SOCIETAL-METABOLIC SYSTEM OF THE STATE: EXPERIENCE OF SYNTHETIC RESEARCH. THE ELECTRONIC MANUAL. SIB-Expertise, December 2023. http://dx.doi.org/10.12731/er0756.18122023.
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This electronic manual presents a number of theoretical and methodological tools based on the key concept: “societal (social) metabolism.” In summary, the synthetic concept of societal metabolism goes beyond the perspective of traditional social sciences by contextualizing the biophysical dimension of metabolic exchange between society and nature. Distancing from reductionist approaches, the interdisciplinary concept of societal metabolism recognizes the importance of mutual connections and interactions of factors of material and social exchange, within the framework of established individual and group social practices in the life of society. The electronic manual will be useful to undergraduate and graduate students studying social and political sciences, and to anyone interested in the theory and practice of applying interdisciplinary approaches to social science problems.
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Croteau, R. [Regulation of terpene metabolism]. Office of Scientific and Technical Information (OSTI), January 1991. http://dx.doi.org/10.2172/6984681.
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Croteau, R. [Regulation of terpene metabolism]. Office of Scientific and Technical Information (OSTI), November 1989. http://dx.doi.org/10.2172/6984921.
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Croteau, Rodney. Regulation of Terpene Metabolism. Office of Scientific and Technical Information (OSTI), March 2004. http://dx.doi.org/10.2172/822599.
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Croteau, R. [Regulation of terpene metabolism]. Office of Scientific and Technical Information (OSTI), January 1992. http://dx.doi.org/10.2172/6687649.
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Starr, Robert C., Brennon R. Orr, M. Hope Lee, and Mark Delwiche. Final Project Report - Coupled Biogeochemical Process Evaluation for Conceptualizing Trichloriethylene Co-Metabolism: Co-Metabolic Enzyme Activity Probes and Modeling Co-Metabolism and Attenuation. Office of Scientific and Technical Information (OSTI), February 2010. http://dx.doi.org/10.2172/972652.
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Schaffer, Arthur A., D. Mason Pharr, Joseph Burger, James D. Burton, and Eliezer Zamski. Aspects of Sugar Metabolism in Melon Fruit as Determinants of Fruit Quality. United States Department of Agriculture, September 1994. http://dx.doi.org/10.32747/1994.7568770.bard.
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The cucurbit family, including melon, translocates the galactosyl-sucrose oligosaccharides, raffinose and stachyose, in addition to sucrose, from the source leaves to the fruit sink. The metabolism of these photoassimilates in the fruit sink controls fruit growth and development, including the horticulturally important phenomenon of sucrose accumulation, which determines melon fruit sweetness. During this research project we have characterized the complete pathway of galactosyl sucrose metabolism in developing fruit, from before anthesis until maturity. We have also compared the metabolic pathway in scurose accumulating genotypes, as compared to non-accumulating genotypes. Furthermore, we studied the pathway in different fruit tissues, in response to pollination, and also analyzed the response of the individual steps of the pathway to perturbations such as low temperature and leaf removal. The results of our studies have led to the conclusion that generally galactosyl-sucrose metabolism functions as a coordinately controlled pathway. In one case, as an immediate response to the absence of pollination, the activity of a single enzyme, UDPglu pyrophosphorylase, was drastically reduced. However, during young fruit development, sucrose accumulation, and in response to perturbations of the system, groups of enzymes, rather than single enzymes, respond in a concerted manner. Our research has characterized in detail the initial enzymes of galactosyl-sucrose metabolism, including the galactosidases, galactokinase and the UDPgal- and UDPglu pyrophosphorylases. We have discovered a novel alkaline a-galactoside which hydrolyzes both stachyose and reaffinose and thereby may have solved the dilemma of cytosolic-sucrose metabolism, since prior to this research there was no known alkaline a-galactosidase capable of hydrolyzing raffinose.