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111.
Lin Yu-Jia Roa-Ureta Ruben H. Basali Abdullajid Usama Alcaria Joselito Francis Albaran Lindo Reynaldo Qurban Mohammad A. Prihartato Perdana K. Qasem Ali Rabaoui Lotfi 《Coral reefs (Online)》2021,40(6):1741-1756
Coral Reefs - The Arabian Gulf is a natural laboratory to examine how subtropical coral reef ecosystems might change in responding to recurring heating events because of uniquely high water... 相似文献
112.
113.
Karoline Ceron Luiz Gustavo R. Oliveira‐Santos Camila S. Souza Daniel O. Mesquita Francis L. S. Caldas Andra C. Araujo Diego J. Santana 《Oikos》2019,128(11):1537-1548
Life on Earth is supported by an infinite number of interactions among organisms. Species interactions in these networks are influenced by latitude, evolutionary history and species traits. We performed a global‐scale literature analysis to build up a database of interactions between anuran communities and their preys, from a wide range of geographical areas, using a network approach. For this purpose, we compiled a total of 55 weighted anuran–prey interaction networks, 39 located in the tropics and 16 in temperate areas. We tested the influence of latitude, as well as anuran taxonomic, functional and phylogenetic richness on network metrics. We found that anuran–prey networks are not nested, exhibit low complementary specialization and modularity and high connectance when compared to other types of networks. The main effects on network metrics were related to latitude, followed by anuran taxonomic, functional and phylogenetic richness, a pattern similar to the emerging in mutualistic networks. Our study is the first integrated analysis of the structural patterns in anuran–prey antagonistic interaction networks in different parts of the world. We suggest that different processes, mediated mainly by latitude, are modeling the architecture of anuran–prey networks across the globe. 相似文献
114.
Muhali Olaide Jimoh Anthony Jide Afolayan Francis Bayo Lewu 《Saudi Journal of Biological Sciences》2020,27(12):3570-3580
This study investigated variations in the concentration of nutrients, antinutrients and mineral content of Amaranthus caudatus harvested from different soil types at various stages of maturity. Four out the five soils namely; sandy clay loam, silty clay loam, clayey loam and loam were experimentally formulated from primary particles of silt, clay and sand in line with the United State Department of Agriculture’s (USDA) soil triangle protocol. The unfractionated soil was used as the control. After harvesting at pre-flowering (61 days after planting), flowering (71 days after planting) and post-flowering (91 days after planting) stages, nutrient and antinutrient analyses were carried out following Association of Official Analytical Chemists (AOAC) and other referenced methods while the Inductively Coupled Plasma- Optical Emission Spectrometer was used to determine mineral compositions of the plant samples. The results of the study revealed that particle size and physicochemical properties of the soil influenced the number of minerals deposited in plant tissues. It was further observed that the nutritional properties of the plant change as plant ages. For an optimal yield of vitamins A and E, clayey loam proved to be the best soil particularly when A. caudatus is harvested before flowering but for vitamin C, sandy clayey loam yielded the highest output at the same stage. Similarly, clayey loam and loam soils yielded the highest proximate compositions at flowering and pre-flowering; however, mineral elements (micro and macro) were highest in control and loam soils. 相似文献
115.
Glycerol-3-phosphate dehydrogenase (G3PDH; E.C.1.1.1.8) was purified from liver and skeletal muscle of black-tailed prairie
dogs (Cynomys ludivicianus), a hibernating species. Native and subunit molecular masses of the dimeric enzyme were 77 and 40 kD, respectively, and both
tissues contained a single isozyme with a pI of 6.4. Kinetic parameters of purified G3PDH from prairie dog liver and muscle
were characterized at 22 and 5 °C and compared with rabbit muscle G3PDH. Substrate affinities for hibernator muscle G3PDH
were stable (NAD) or increased significantly (Km G3P and DHAP decreased) at low temperature whereas Km NAD and DHAP of rabbit G3PDH increased. Prairie dog G3PDH showed greater conservation of Km G3P over a wide temperature range as well as greater thermal stability and resistance to chemical denaturation by guanidine
hydrochloride than the rabbit enzyme. In addition, using the protein sequence of the hibernating thirteen-lined ground squirrel
(Ictidomys tridecemlineatus) and bioinformatics tools, the deduced protein structure of G3PDH was compared between heterothermic and homeothermic mammals.
Structural and functional characteristics of G3PDH from the hibernating species would support enzyme function over a wide
range of core body temperatures over cycles of torpor and arousal. 相似文献
116.
ABSTRACT: BACKGROUND: HBB, IL4, IL12, TNF, LTA, NCR3 and FCGR2A polymorphisms have been associated with malaria resistance in humans, whereas cytophilic immunoglobulin G (IgG) antibodies are thought to play a critical role in immune protection against asexual blood stages of the parasite. Furthermore, HBB, IL4, TNF, and FCGR2A have been associated with both malaria resistance and IgG levels. This suggests that some malaria resistance genes influence the levels of IgG subclass antibodies. METHODS: In this study, the effect of HBB, IL4, IL12, TNF, LTA, NCR3 and FCGR2A polymorphisms on the levels of IgG responses against Plasmodium falciparum blood-stage extract was investigated in 220 individuals living in Burkina Faso. The Pearson's correlation coefficient among IgG subclasses was determined. A family-based approach was used to assess the association of polymorphisms with anti-P. falciparum IgG, IgG1, IgG2, IgG3 and IgG4 levels. RESULTS: After applying a multiple test correction, several polymorphisms were associated with IgG subclass or IgG levels. There was an association of i) haemoglobin C with IgG levels; ii) the FcgammaRIIa H/R131 with IgG2 and IgG3 levels; iii) TNF-863 with IgG3 levels; iv) TNF-857 with IgG levels; and, v) TNF1304 with IgG3, IgG4, and IgG levels. CONCLUSION: Taken together, the results support the hypothesis that some polymorphisms affect malaria resistance through their effect on the acquired immune response, and pave the way towards further comprehension of genetic control of an individual's humoral response against malaria. 相似文献
117.
T cell-induced secretion of MHC class II-peptide complexes on B cell exosomes 总被引:4,自引:0,他引:4 下载免费PDF全文
Antigen-specific interactions between B cells and T cells are essential for the generation of an efficient immune response. Since this requires peptide–MHC class II complexes (pMHC-II) on the B cell to interact with TCR on antigen-specific T cells, we have examined the mechanisms regulating the persistence, loss, and secretion of specific pMHC-II complexes on activated B cells. Using a mAb that recognizes specific pMHC-II, we found that activated B cells degrade approximately 50% of pMHC-II every day and release 12% of these pMHC-II from the cell on small membrane vesicles termed exosomes. These exosomes directly stimulate primed, but not naïve, CD4 T cells. Interestingly, engagement of antigen-loaded B cells with specific CD4 T cells stimulates exosome release in a manner that can be mimicked by pMHC-II crosslinking. Biochemical studies revealed that the pMHC-II released on exosomes was previously expressed on the plasma membrane of the B cells, suggesting that regulated exosome release from activated B cells is a mechanism to allow pMHC-II to escape intracellular degradation and decorate secondary lymphoid organs with membrane-associated pMHC-II complexes. 相似文献
118.
Michel de Bandt Bruno Fautrel Jean Francis Maillefert Jean Marie Berthelot Bernard Combe René-Marc Flipo Frédéric Lioté Olivier Meyer Alain Saraux Daniel Wendling Xavier Le Loët Francis Guillemin 《Arthritis research & therapy》2009,11(5):1-8
Introduction
The aim of this study was to determine a low disease activity threshold - a 28-joint disease activity score (DAS28) value - for the decision to maintain unchanged disease-modifying antirheumatic drug (DMARD) treatment in rheumatoid arthritis patients, based on expert opinion.Methods
Nine hundred and sixty-seven case scenarios with various levels for each component of the DAS28 (resulting in a disease activity score between 2 and 3.2) were presented to 44 panelists. For each scenario, panelists had to decide whether or not DMARD treatment (excluding steroids) could be maintained unchanged. In each scenario, for decision, the participants were given the DAS28 parameters, without knowledge of the resultant DAS28. The relationship between panelists' decision, DAS28 value, and components of the score were analysed by multiple logistic regression analysis. Each panelist analysed 160 randomised scenarios. Intra-rater and inter-rater reproducibility were assessed.Results
Forty-four panelists participated in the study. Inter-panelist agreement was good (κ = 0.63; 95% confidence interval = 0.61 to 0.65). Intra-panelist agreement was excellent (κ = 0.87; 95% confidence interval = 0.82 to 0.92). Quasi-perfect agreement was observed for DAS28 ≤ 2.4, less pronounced between 2.5 and 2.9, and almost no agreement for DAS28 > 3.0. For values below 2.5, panelists agreed to maintain unchanged DMARDs; for values above 2.5, discrepancies occurred more frequently as the DAS28 value increased. Multivariate analysis confirmed the relationship between panelist's decision, DAS28 value and components of the DAS28. Between DAS28 of 2.4 and 3.2, a major determinant for panelists' decision was swollen joint count. Female and public practice physicians decided more often to maintain treatment unchanged.Conclusions
As a conclusion, panelists suggested that in clinical practice there is no need to change DMARD treatment in rheumatoid arthritis patients with DAS28 ≤ 2.4. 相似文献119.
About 200 micromammal isolated teeth (rodents, lagomorphs) originating from the middle Orleanian locality of Béon 2 (Montréal-du-Gers, SW France) are described. The rodent fauna is dominated by myomorphs (7 species), including the cricetid Democricetodon aff. hispanicus Fahlbusch, the melissiodontid Melissiodon sp., the glirids Peridyromys murinus (Pomel), Pseudodryomys aff. ibericus, Pseudodryomys aff. simplicidens, and Glirudinus modestus (Dehm), and the eomyid Ligerimys aff. florancei. Sciuromorphs are represented only by Heteroxerus rubricati Crusafont, Villalta and Truyols. Within lagomorphs, 2 dental morphs referred to the ochotonid Prolagus Pomel are identified in Béon 2. They correspond to Prolagus oeningensis (König) and P. aff. vasconiensis. On a biostratigraphical point of view, this study confirms the location of Béon 2 at the early part of the MN4; this locality is older than other regional sites such as Pellecahus, Béon 1, La Romieu, and Bézian (MN4b), and it is coeval to Artenay, in the Loire basin. In particular, glirids and lagomorphs from Béon 2 testify to close relationships with micromammal localities referred to the MN3 biozone. 相似文献
120.