882 resultados para metabolism and cognition
Resumo:
Oceans are experiencing increasing acidification in parallel to a distinct warming trend in consequence of ongoing climate change. Rising seawater temperatures are mediating a northward shift in distribution of Atlantic cod (Gadus morhua), into the habitat of polar cod (Boreogadus saida), that is associated with retreating cold water masses. This study investigates the competitive strength of the co-occurring gadoids under ocean acidification and warming (OAW) scenarios. Therefore, we incubated specimens of both species in individual tanks for 4 months, under different control and projected temperatures (polar cod: 0, 3, 6, 8 °C, Atlantic cod: 3, 8, 12, 16 °C) and PCO2 conditions (390 and 1170 µatm) and monitored growth, feed consumption and standard metabolic rate. Our results revealed distinct temperature effects on both species. While hypercapnia by itself had no effect, combined drivers caused nonsignificant trends. The feed conversion efficiency of normocapnic polar cod was highest at 0 °C, while optimum growth performance was attained at 6 °C; the long-term upper thermal tolerance limit was reached at 8 °C. OAW caused only slight impairments in growth performance. Under normocapnic conditions, Atlantic cod consumed progressively increasing amounts of feed than individuals under hypercapnia despite maintaining similar growth rates during warming. The low feed conversion efficiency at 3 °C may relate to the lower thermal limit of Atlantic cod. In conclusion, Atlantic cod displayed increased performance in the warming Arctic such that the competitive strength of polar cod is expected to decrease under future OAW conditions.
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Preeclampsia (PE) is a pregnancy complication that is new-onset of hypertension and proteinuria after 20 weeks of gestation. However, subclinical renal dysfunction may be apparent earlier in gestation prior to the clinical presentation of PE. Although the maternal syndrome of PE resolves early postpartum, women with a history of PE are at higher risk of renal dysfunction later in life. Mineral metabolism, such as phosphate balance is heavily dependent on renal function, yet, phosphate handling in women with a history of PE is largely unknown. To investigate whether women with a history of PE would exhibit changes in phosphate metabolism compared to healthy parous women, phosphate loading test was used. Women with or without a history of PE, who were 6 months to 5 years postpartum, were recruited for this study. Blood and urine samples were collected before and after the oral dosing of 500mg phosphate solution. Biochemical markers of phosphate metabolism and renal function were evaluated. In order to assess the difference in renal function alteration between first trimester women who were or were not destined to develop PE, plasma cystatin C concentration was analysed. After phosphate loading, women with a history of PE had significantly elevated serum phosphate at both 1- and 2-hour, while controls had higher urine phosphate:urine creatinine excretion ratio at 1-hour than women with a history of PE. Women with a history of PE had no changes in intact parathyroid hormone (iPTH) concentration throughout the study period, whereas controls had elevated iPTH at 1-hour from baseline. In terms of renal function in the first trimester, there was no difference in plasma cystatin C concentration between women who were or were not destined to develop PE. The elevation of serum phosphate in women with a history of PE could be due to the delay in phosphate excretion. Prolong elevation of serum phosphate can have serious consequences later in life. Thus, oral phosphate challenge may serve as a useful method of early screening for altered phosphate metabolism and renal function.
Resumo:
Preeclampsia (PE) is a pregnancy complication that is new-onset of hypertension and proteinuria after 20 weeks of gestation. However, subclinical renal dysfunction may be apparent earlier in gestation prior to the clinical presentation of PE. Although the maternal syndrome of PE resolves early postpartum, women with a history of PE are at higher risk of renal dysfunction later in life. Mineral metabolism, such as phosphate balance is heavily dependent on renal function, yet, phosphate handling in women with a history of PE is largely unknown. To investigate whether women with a history of PE would exhibit changes in phosphate metabolism compared to healthy parous women, phosphate loading test was used. Women with or without a history of PE, who were 6 months to 5 years postpartum, were recruited for this study. Blood and urine samples were collected before and after the oral dosing of 500mg phosphate solution. Biochemical markers of phosphate metabolism and renal function were evaluated. In order to assess the difference in renal function alteration between first trimester women who were or were not destined to develop PE, plasma cystatin C concentration was analysed. After phosphate loading, women with a history of PE had significantly elevated serum phosphate at both 1- and 2-hour, while controls had higher urine phosphate:urine creatinine excretion ratio at 1-hour than women with a history of PE. Women with a history of PE had no changes in intact parathyroid hormone (iPTH) concentration throughout the study period, whereas controls had elevated iPTH at 1-hour from baseline. In terms of renal function in the first trimester, there was no difference in plasma cystatin C concentration between women who were or were not destined to develop PE. The elevation of serum phosphate in women with a history of PE could be due to the delay in phosphate excretion. Prolong elevation of serum phosphate can have serious consequences later in life. Thus, oral phosphate challenge may serve as a useful method of early screening for altered phosphate metabolism and renal function.
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The richness of dance comes from the need to work with an individual body. Still, the body of the dancer belongs to plural context, crossed by artistic and social traditions, which locate the artists in a given field. We claim that role conflict is an essential component of the structure of collective artistic creativity. We address the production of discourse in a British dance company, with data that spawns from the ethnography ‘Dance and Cognition’, directed by David Kirsh at the University of California, together with WayneMcGregor-Random Dance. Our Critical Discourse Analysis is based on multiple interviews to the dancers and choreographer. Our findings show how creativity in dance seems to be empirically observable, and thus embodied and distributed shaped by the dance habitus of the particular social context.
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To further investigate the importance of insulin signaling in the growth, development, sexual maturation and egg production of adult schistosomes, we have focused attention on the insulin receptors (SjIRs) of Schistosoma japonicum, which we have previously cloned and partially characterised. We now show, by Biolayer Interferometry, that human insulin can bind the L1 subdomain (insulin binding domain) of recombinant (r)SjIR1 and rSjIR2 (designated SjLD1 and SjLD2) produced using the Drosophila S2 protein expression system. We have then used RNA interference (RNAi) to knock down the expression of the SjIRs in adult S. japonicum in vitro and show that, in addition to their reduced transcription, the transcript levels of other important downstream genes within the insulin pathway, associated with glucose metabolism and schistosome fecundity, were also impacted substantially. Further, a significant decrease in glucose uptake was observed in the SjIR-knockdown worms compared with luciferase controls. In vaccine/challenge experiments, we found that rSjLD1 and rSjLD2 depressed female growth, intestinal granuloma density and faecal egg production in S. japonicum in mice presented with a low dose challenge infection. These data re-emphasize the potential of the SjIRs as veterinary transmission blocking vaccine candidates against zoonotic schistosomiasis japonica in China and the Philippines.
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Introduction: Obestatin is a controversial gastrointestinal peptide purported to have metabolic actions.
Objectives: This study investigated whether treatment with a stable obestatin analogue (PEG-OB(Cys10, Cys13)) changed plasma metabolite levels firstly in lean and subsequently in diet-induced obesity (DIO) C57BL6/J mice.
Methods: Untargeted LC-HRMS metabolomics experiments were carried out in ESI + mode with plasma extracts from both groups of animals. Data were normalised, multivariate and univariate statistical analysis performed and metabolites of interest putatively identified.
Results: In lean mice, 39 metabolites were significantly changed by obestatin treatment and the majority of these were increased, including various C16 and C18 moieties of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and monoacylglycerol, along with vitamin A, vitamin D3, tyrosine, acetylcarnitine and 2α-(hydroxymethyl)-5α-androstane-3β,17β-diol. Decreased concentrations of glycolithocholic acid, 3-dehydroteasterone and various phospholipids were observed. In DIO mice, 25 metabolites were significantly affected and strikingly, the magnitudes of changes here were generally much greater in DIO mice than in lean mice, and in contrast, the majority of metabolite changes were decreases. Four metabolites affected in both groups included glycolithocholic acid, and three different long-chain (C18) phospholipid molecules (phosphatidylethanolamine, platelet activating factor (PAF), and monoacylglycerol). Metabolites exclusively affected in DIO mice included various phosphatidylcholines, lysophosphatidylcholines and fatty acyls, as well as creatine and oxidised glutathione.
Conclusion: This investigation demonstrates that obestatin treatment affects phospholipid turnover and influences lipid homeostasis, whilst providing convincing evidence that obestatin may be acting to ameliorate diet-induced impairments in lipid metabolism, and it may influence steroid, bile acid, PAF and glutathione metabolism.
Resumo:
Scavenger receptor BI (SR-BI) is the major receptor for high-density lipoprotein (HDL)
cholesterol (HDL-C). In humans, high amounts of HDL-C in plasma are associated with a
lower risk of coronary heart disease (CHD). Mice that have depleted Scarb1 (SR-BI
knockout mice) have markedly elevated HDL-C levels but, paradoxically, increased
atherosclerosis. The impact of SR-BI on HDL metabolism and CHD risk in humans remains
unclear. Through targeted sequencing of coding regions of lipid-modifying genes in 328
individuals with extremely high plasma HDL-C levels, we identified a homozygote for a lossof-function
variant, in which leucine replaces proline 376 (P376L), in SCARB1, the gene
encoding SR-BI. The P376L variant impairs posttranslational processing of SR-BI and
abrogates selective HDL cholesterol uptake in transfected cells, in hepatocyte-like cells
derived from induced pluripotent stem cells from the homozygous subject, and in mice.
Large population-based studies revealed that subjects who are heterozygous carriers of
the P376L variant have significantly increased levels of plasma HDL-C. P376L carriers have
a profound HDL-related phenotype and an increased risk of CHD (odds ratio = 1.79, which is
statistically significant).
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[EN]GH is main regulator of body growth and composition, somatic development, intermediate metabolism and gender-dependent dimorphism in mammals. The liver is a direct target of estrogens because it expresses estrogen receptors which are connected with development, lipid metabolism and insulin sensitivity, hepatic carcinogenesis, protection from drug-induced toxicity and fertility. In addition, estrogens can modulate GH actions in liver by acting centrally, regulating pituitary GH secretion, and, peripherally, by modulating GHR-JAK2-STAT5 signalling pathway
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On 2 July 2009, the EFSA Panel on Dietetic products, Nutrition and Allergies (NDA) endorsed a draft Opinion on Dietary Reference Values for fats to be released for public consultation. This Scientific Report summarises the comments received through the public consultation and outlines how these were taken into account in the final opinion. EFSA had received contributions from 40 interested parties (individuals, non-governmental organisations, industry organisations, academia and national assessment bodies). The main comments which were received during the public consultation related to: the availability of more recent data, the nomenclature used, the use of a non-European food composition data base, the impact of genetic factors in modulating the absorption, metabolism and health effects of different fatty acids, the definition of “nutritionally adequate diet”, the use of Dietary Reference Values in the labelling of foods, the translation of advice into food-based dietary guidelines, nutrient goals and recommendations, certain risk management issues, and to Dietary Reference Values of fats, individual fatty acids, and cholesterol. All the public comments received that related to the remit of EFSA were assessed and the Opinion on Dietary Reference Values for fats has been revised taking relevant comments into consideration.
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Developing a theoretical framework for pervasive information environments is an enormous goal. This paper aims to provide a small step towards such a goal. The following pages report on our initial investigations to devise a framework that will continue to support locative, experiential and evaluative data from ‘user feedback’ in an increasingly pervasive information environment. We loosely attempt to outline this framework by developing a methodology capable of moving from rapid-deployment of software and hardware technologies, towards a goal of realistic immersive experience of pervasive information. We propose various technical solutions and address a range of problems such as; information capture through a novel model of sensing, processing, visualization and cognition.
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Thesis (Ph.D.)--University of Washington, 2016-06
Resumo:
Seals must manage their energy reserves carefully while they fast on land to ensure that they go to sea with sufficient fuel to sustain them until they find food. Glucocorticoids (GCs) have been implicated in the control of fuel metabolism and termination of fasting in pinnipeds. Here we tested the hypothesis that dexamethasone, an artificial GC, increases fat and protein catabolism, and induces departure from the breeding colony in wild, fasting grey seal pups. A single intramuscular dose of dexamethasone completely suppressed cortisol production for 24–72 h, demonstrating activation of GC receptors. In experiment 1, we compared the effects of a single dose of dexamethasone or saline administered 10 days after weaning on fasting mass and body composition changes, cortisol, blood urea nitrogen (BUN) and glucose levels, and timing of departure from the colony. In experiment 2, we investigated the effects of dexamethasone on short-term (5 days) changes in mass loss, body composition and BUN levels. In experiment 1, dexamethasone induced a short-lived increase in mass loss, but there was no difference in timing of departure between dexamethasone- and saline-treated pups (N=10). In experiment 2, dexamethasone increased protein and water loss and prevented a decrease in BUN levels (N=11). Our data suggest changes in cortisol contribute to regulation of protein catabolism in fasting seal pups, irrespective of the sex of the animal, but do not terminate fasting. By affecting the rate of protein depletion, lasting changes in cortisol levels could influence the amount of time seal pups have to find food, and thus may have important consequences for their survival.
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Leptin is a multifunctional hormone, produced predominantly in adipocytes. It regulates energy balance through its impact on appetite and fat metabolism, and its concentration indicates the size of body fat reserves. Leptin also plays a vital role in stretch-induced surfactant production during alveolar development in the fetus. The structure, expression pattern, and role of leptin have not previously been explored in marine mammals. Phocid seals undergo cyclical changes in body composition as a result of prolonged fasting and intensive foraging bouts and experience rapid, dramatic, and repeated changes in lung volume during diving. Here, we report the tissue-specific expression pattern of leptin in these animals. This is the first demonstration of leptin expression in the lung tissue of a mature mammal, in addition to its expression in the blubber and bone marrow, in common with other animals. We propose a role for leptin in seal pulmonary surfactant production, in addition to its likely role in long-term energy balance. We identify substitutions in the phocine leptin sequence in regions normally highly conserved between widely distinct vertebrate groups, and, using a purified seal leptin antiserum, we confirm the presence of the leptin protein in gray seal lung and serum fractions. Finally, we report the substantial inadequacies of using heterologous antibodies to measure leptin in unextracted gray seal serum.
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Intellectual disability and cerebellar atrophy occur together in a large number of genetic conditions and are frequently associated with microcephaly and/or epilepsy. Here we report the identification of causal mutations in Sorting Nexin 14 (SNX14) found in seven affected individuals from three unrelated consanguineous families who presented with recessively inherited moderate-severe intellectual disability, cerebellar ataxia, early-onset cerebellar atrophy, sensorineural hearing loss, and the distinctive association of progressively coarsening facial features, relative macrocephaly, and the absence of seizures. We used homozygosity mapping and whole-exome sequencing to identify a homozygous nonsense mutation and an in-frame multiexon deletion in two families. A homozygous splice site mutation was identified by Sanger sequencing of SNX14 in a third family, selected purely by phenotypic similarity. This discovery confirms that these characteristic features represent a distinct and recognizable syndrome. SNX14 encodes a cellular protein containing Phox (PX) and regulator of G protein signaling (RGS) domains. Weighted gene coexpression network analysis predicts that SNX14 is highly coexpressed with genes involved in cellular protein metabolism and vesicle-mediated transport. All three mutations either directly affected the PX domain or diminished SNX14 levels, implicating a loss of normal cellular function. This manifested as increased cytoplasmic vacuolation as observed in cultured fibroblasts. Our findings indicate an essential role for SNX14 in neural development and function, particularly in development and maturation of the cerebellum.
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The Picornaviridae family consists of positive-strand RNA viruses that are the causative agents of a variety of diseases in humans and animals. Few drugs targeting picornaviruses are available, making the discovery of new antivirals a high priority. Here, we identified and characterized three compounds from a library of kinase inhibitors that block replication of poliovirus, coxsackievirus B3, and encephalomyocarditis virus. The antiviral effect of these compounds is not likely related to their known cellular targets because other inhibitors targeting the same pathways did not inhibit viral replication. Using an in vitro translation-replication system, we showed that these drugs inhibit different stages of the poliovirus life cycle. A4(1) inhibited the formation of a functional replication complex, while E5(1) and E7(2) affected replication after the replication complex had formed. A4(1) demonstrated partial protection from paralysis in a murine model of poliomyelitis. Poliovirus resistant to E7(2) had a single mutation in the 3A protein. This mutation was previously found to confer resistance to enviroxime-like compounds, which target either PI4KIIIβ (major enviroxime-like compounds) or OSBP (minor enviroxime-like compounds), cellular factors involved in lipid metabolism and shown to be important for replication of diverse positive-strand RNA viruses. We classified E7(2) as a minor enviroxime-like compound, because the localization of OSBP changed in the presence of this inhibitor. Interestingly, both E7(2) and major enviroxime-like compound GW5074 interfered with the viral polyprotein processing. Multiple attempts to isolate resistant mutants in the presence of A4(1) or E5(1) were unsuccessful, showing that effective broad-spectrum antivirals could be developed on the basis of these compounds. Studies with these compounds shed light on pathways shared by diverse picornaviruses that could be potential targets for the development of broad-spectrum antiviral drugs.