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81.
Benzler Martin Benzler Jonas Stoehr Sigrid Hempp Cindy Rizwan Mohammed Z. Heyward Phil Tups Alexander 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2019,189(3-4):413-424
Journal of Comparative Physiology B - Saturated fatty acids are implicated in the development of metabolic diseases, including obesity and type 2 diabetes. There is evidence, however, that... 相似文献
82.
Rebholz-Schuhmann D Kirsch H Arregui M Gaudan S Riethoven M Stoehr P 《Bioinformatics (Oxford, England)》2007,23(2):e237-e244
To allow efficient and systematic retrieval of statements from Medline we have developed EBIMed, a service that combines document retrieval with co-occurrence-based analysis of Medline abstracts. Upon keyword query, EBIMed retrieves the abstracts from EMBL-EBI's installation of Medline and filters for sentences that contain biomedical terminology maintained in public bioinformatics resources. The extracted sentences and terminology are used to generate an overview table on proteins, Gene Ontology (GO) annotations, drugs and species used in the same biological context. All terms in retrieved abstracts and extracted sentences are linked to their entries in biomedical databases. We assessed the quality of the identification of terms and relations in the retrieved sentences. More than 90% of the protein names found indeed represented a protein. According to the analysis of four protein-protein pairs from the Wnt pathway we estimated that 37% of the statements containing such a pair mentioned a meaningful interaction and clarified the interaction of Dkk with LRP. We conclude that EBIMed improves access to information where proteins and drugs are involved in the same biological process, e.g. statements with GO annotations of proteins, protein-protein interactions and effects of drugs on proteins. AVAILABILITY: Available at http://www.ebi.ac.uk/Rebholz-srv/ebimed 相似文献
83.
Enantiodifferentiation of methyl mandelate by β-Cyclodextrin in the liquid phase is explored in detail. Temperature dependent studies using a β-cyclodextrin chiral stationary phase provided differential binding enthalpies and entropies. NMR studies revealed where around the host molecule the guest tends to reside. Molecular dynamics simulations correctly predict the retention order and provide an atomistic account of how chiral discrimination takes place. It is found that short range dispersion forces rather than long range coulombic forces are responsible for both complexation and for enantiodiscrimination. The intermolecular hydrogen bonds are not discriminating and the idea that a tight fit of included species within a cyclodextrin cavity be a requirement for chiral discrimination is questioned. © 1996 Wiley-Liss, Inc. 相似文献
84.
Cheryl A. D. Wilga Ashley A. Stoehr Danielle C. Duquette Rebecca M. Allen 《Environmental Biology of Fishes》2012,95(1):155-167
Feeding behavior in the species of captive chondrichthyans is studied to clarify the functional mechanisms responsible for feeding ecology. Kinematics and pressure in the buccal, hyoid and pharyngeal regions were quantified in Squalus acanthias, Chiloscyllium plagiosum and Leucoraja erinacea using sonomicrometry and pressure transducers. Means and coefficients of variation were analyzed by species and by behavior to test for stereotypy and flexibility in the feeding mechanism. Several instances of mechanical stereotypy as well as flexibility were found in the feeding kinematics and pressure of the three chondrichthyan species. In general, Squalus acanthias shows more stereotyped feeding behavior than C. plagiosum and L. erinacea. Different aspects of feeding behavior stand out among the three species. Chiloscyllium plagiosum generates lowest pressures, S. acanthias achieves the greatest area changes, and L. erinacea has longer durations for manipulating prey. Capture events are functionally and behaviorally stereotyped while processing events are functionally and behaviorally flexible with the ability to use suction or compression to process the same food item. Squalus acanthias is a functional specialist and C. plagiosum is functionally a generalist, with both species exhibiting behavioral flexibility. Leucoraja erinacea is a functional and behavioral generalist. Using functional morphology to explain mechanical stereotypy and flexibility in the feeding behavior of three suction feeding chondrichthyan species has allowed a better understanding of specialist and generalist trophic behaviors. 相似文献
85.
Termite cohabitation: the relative effect of biotic and abiotic factors on mound biodiversity
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ALESSANDRA MARINS DIOGO COSTA LAURA RUSSO COLIN CAMPBELL OG DESOUZA OTTAR N. BJØRNSTAD KATRIONA SHEA 《Ecological Entomology》2016,41(5):532-541
1. Termites are important ecosystem engineers that improve primary productivity in trees and animal diversity outside their mounds. However, their ecological relationship with the species nesting inside their mounds is poorly understood. 2. The presence of termite cohabitant colonies inside 145 Cornitermes cumulans mounds of known size and location was recorded. Using network‐theoretical methods in conjunction with a suite of statistical analyses, the relative influence of biotic and abiotic drivers of termite within‐mound diversity on the composition and species richness of the termite community was investigated, specifically builder presence and physical aspects of the mound. 3. We found that richness inside the mound increases with mound size, and the species similarity between mounds decreases with distance. The physical attributes (abiotic drivers) of termite mounds (size and relative distance to other mounds) are the strongest predictors of termite species richness and composition. The biotic driver (presence of a builder colony) has an important, though smaller, negative effect on within‐mound termite species richness. 4. The findings suggest that the termites' physical manipulation of their environment is an important driver of within‐mound community diversity. More generally, the approach taken here, using a combination of statistical and network‐theoretical methods, can be used to determine the relative importance of abiotic and biotic drivers of diversity in a wide range of communities of interacting species. 相似文献
86.
ABSTRACT There are many challenges facing natural resources programs in North American higher education today. Pressures exerted by a new generation of students, changing workplace requirements (including undergraduate core-knowledge requirements), and an increasingly specialized professoriate are great but not insurmountable. We discuss each of these issues and pose potential solutions to address each including adopting new pedagogical techniques for content delivery (e.g., adapting courses to be inclusive of new technologies), revising curriculum to meet the needs of a new suite of learners (e.g., developing curricula that allow structured flexibility of choices, designing a core curriculum that is a mix of single-discipline courses and courses that integrate across disciplines), and new strategies for faculty engagement in discipline-specific survey courses. By remaining deliberate and effective in our pursuit of quality higher education we have the opportunity to ensure we are delivering the best possible education to the future professionals of our disciplines. 相似文献
87.
Kinga Tóth Ferenc Sipos Alexandra Kalmár árpád V. Patai Barnabás Wichmann Robert Stoehr Henriette Golcher Vera Schellerer Zsolt Tulassay Béla Molnár 《PloS one》2012,7(9)
Background
Methylated Septin 9 (SEPT9) is a sensitive biomarker for colorectal cancer (CRC) from peripheral blood. However, its relationship to cancer localization, guaiac-based fecal occult blood test (gFOBT) and carcinoembryonic antigen (CEA) have not been described.Methodology/Principal Findings
Plasma samples were collected for SEPT9 analysis from patients with no evidence of disease (NED) (n = 92) before colonoscopy and CRC (n = 92) before surgical treatment. DNA was isolated and bisulfite-converted using Epi proColon kit 2.0. Qualitative determination was performed using Epi proColon 2.0 RT-PCR assay. Samples for gFOBT and CEA analysis were collected from NED (n = 17 and 27, respectively) and CRC (n = 22 and 27, respectively). SEPT9 test was positive in 15.2% (14/92) of NED and 95.6% (88/92) of CRC, including 100% (67/67) from stage II to stage IV CRC and 84% (21/25) of stage I CRC when a sample was called positive if 1 out of 3 PCR replicates was positive. In a second analysis (2 out of 3 PCR replicates) specificity improved to 99% (91/92) of NEDs, at a sensitivity of 79.3% (73/92) of SEPT9 positives in CRC. gFOBT was positive in 29.4% (5/17) of NED and 68.2% (15/22) of CRC and elevated CEA levels were detected in 14.8% (4/27) of NED and 51.8% (14/27) of CRC. Both SEPT9 (84.8%) and CEA (85.2%) showed higher specificity than gFOBT (70.6%). SEPT9 was positive in 96.4% (54/56) of left-sided colon cancer (LSCC) cases and 94.4% (34/36) of right-sided colon cancer (RSCC) cases. gFOBT was positive in 83.3% (10/12) of cases with LSCC and 50% (5/10) of cases with RSCC, elevated CEA was detected 60% (9/15) of LSCC and 41.7% (5/12) of RSCC.Conclusions/Significance
The high degree of sensitivity and specificity of SEPT9 in plasma makes it a better method to detect CRC than gFOBT and CEA, even for the more difficult to detect RSCC. 相似文献88.
Bielohuby M Menhofer D Kirchner H Stoehr BJ Müller TD Stock P Hempel M Stemmer K Pfluger PT Kienzle E Christ B Tschöp MH Bidlingmaier M 《American journal of physiology. Endocrinology and metabolism》2011,300(1):E65-E76
Low-carbohydrate/high-fat diets (LC-HFDs) in rodent models have been implicated with both weight loss and as a therapeutic approach to treat neurological diseases. LC-HFDs are known to induce ketosis; however, systematic studies analyzing the impact of the macronutrient composition on ketosis induction and weight loss success are lacking. Male Wistar rats were pair-fed for 4 wk either a standard chow diet or one of three different LC-HFDs, which only differed in the relative abundance of fat and protein (percentages of fat/protein in dry matter: LC-75/10; LC-65/20; LC-55/30). We subsequently measured body composition by nuclear magnetic resonance (NMR), analyzed blood chemistry and urine acetone content, evaluated gene expression changes of key ketogenic and gluconeogenic genes, and measured energy expenditure (EE) and locomotor activity (LA) during the first 4 days and after 3 wk on the respective diets. Compared with chow, rats fed with LC-75/10, LC-65/20, and LC-55/30 gained significantly less body weight. Reductions in body weight were mainly due to lower lean body mass and paralleled by significantly increased fat mass. Levels of β-hydroxybutyate were significantly elevated feeding LC-75/10 and LC-65/20 but decreased in parallel to reductions in dietary fat. Acetone was about 16-fold higher with LC-75/10 only (P < 0.001). In contrast, rats fed with LC-55/30 were not ketotic. Serum fibroblast growth factor-21, hepatic mRNA expression of hydroxymethylglutaryl-CoA-lyase, peroxisome proliferator-activated receptor-γ coactivator-1α, and peroxisome proliferator-activated receptor-γ coactivator-1β were increased with LC-75/10 only. Expression of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase was downregulated by 50-70% in LC-HF groups. Furthermore, EE and LA were significantly decreased in all groups fed with LC-HFDs after 3 wk on the diets. In rats, the absence of dietary carbohydrates per se does not induce ketosis. LC-HFDs must be high in fat, but also low in protein contents to be clearly ketogenic. Independent of the macronutrient composition, LC-HFD-induced weight loss is not due to increased EE and LA. 相似文献
89.
Nawroth R Stellwagen F Schulz WA Stoehr R Hartmann A Krause BJ Gschwend JE Retz M 《PloS one》2011,6(11):e27509
Aberrant activation and mutation status of proteins in the phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) and the mitogen activated protein kinase (MAPK) signaling pathways have been linked to tumorigenesis in various tumors including urothelial carcinoma (UC). However, anti-tumor therapy with small molecule inhibitors against mTOR turned out to be less successful than expected. We characterized the molecular mechanism of this pathway in urothelial carcinoma by interfering with different molecular components using small chemical inhibitors and siRNA technology and analyzed effects on the molecular activation status, cell growth, proliferation and apoptosis. In a majority of tested cell lines constitutive activation of the PI3K was observed. Manipulation of mTOR or Akt expression or activity only regulated phosphorylation of S6K1 but not 4E-BP1. Instead, we provide evidence for an alternative mTOR independent but PI3K dependent regulation of 4E-BP1. Only the simultaneous inhibition of both S6K1 and 4E-BP1 suppressed cell growth efficiently. Crosstalk between PI3K and the MAPK signaling pathway is mediated via PI3K and indirect by S6K1 activity. Inhibition of MEK1/2 results in activation of Akt but not mTOR/S6K1 or 4E-BP1. Our data suggest that 4E-BP1 is a potential new target molecule and stratification marker for anti cancer therapy in UC and support the consideration of a multi-targeting approach against PI3K, mTORC1/2 and MAPK. 相似文献
90.
Catia C. Proenca Natacha Stoehr Mario Bernhard Shanon Seger Christel Genoud Ana Roscic Paolo Paganetti Shanming Liu Leon O. Murphy Rainer Kuhn Tewis Bouwmeester Ivan Galimberti 《PloS one》2013,8(7)
The accumulation of aggregated mutant huntingtin (mHtt) inclusion bodies is involved in Huntigton’s disease (HD) progression. Medium sized-spiny neurons (MSNs) in the corpus striatum are highly vulnerable to mHtt aggregate accumulation and degeneration, but the mechanisms and pathways involved remain elusive. Here we have developed a new model to study MSNs degeneration in the context of HD. We produced organotypic cortico-striatal slice cultures (CStS) from HD transgenic mice mimicking specific features of HD progression. We then show that induction of autophagy using catalytic inhibitors of mTOR prevents MSNs degeneration in HD CStS. Furthermore, disrupting autophagic flux by overexpressing Atg4b in neurons and slice cultures, accelerated mHtt aggregation and neuronal death, suggesting that Atg4b-dependent autophagic flux influences HD progression. Under these circumstances induction of autophagy using catalytic inhibitors of mTOR was inefficient and did not affect mHtt aggregate accumulation and toxicity, indicating that mTOR inhibition alleviates HD progression by inducing Atg4b-dependent autophagic flux. These results establish modulators of Atg4b-dependent autophagic flux as new potential targets in the treatment of HD. 相似文献