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排序方式: 共有346条查询结果,搜索用时 15 毫秒
1.
Josep C. Jiménez-Chillarón Rubén Díaz Débora Martínez Thais Pentinat Marta Ramón-Krauel Sílvia Ribó Torsten Plösch 《Biochimie》2012
Nutrition plays a key role in many aspects of health and dietary imbalances are major determinants of chronic diseases including cardiovascular disease, obesity, diabetes and cancer. Adequate nutrition is particularly essential during critical periods in early life (both pre- and postnatal). In this regard, there is extensive epidemiologic and experimental data showing that early sub-optimal nutrition can have health consequences several decades later. 相似文献
2.
P Vadas K Scott G Smith I Rajkovic E Stefanski B D Schouten R Singh W Pruzanski 《Life sciences》1992,50(11):807-811
Massive elevations of serum phospholipase A2 activity have been documented in patients with septic shock. Serum PLA2 activity correlated to the degree and duration of circulatory collapse, while purified native PLA2 reproduced hypotension in experimental animals. In a prospective study of patients with septic shock, we have determined the relationship of PLA2 enzyme activity to PLA2 immunoreactivity using radiolabelled E. coli phospholipid substrate and an ELISA specific for group II human nonpancreatic PLA2. In all patients, there was a clear concordance of the two assays. Maximal PLA2 concentration was increased a mean of 554-fold over normal levels. We found no evidence to support the presence of activating or inhibitory proteins. These data confirm that the observed increase in serum PLA2 activity in septic shock is due to intravascular release of group II nonpancreatic PLA2. 相似文献
3.
K Schulze R Kairam M Stefanski R Sciacca L S James 《Journal of applied physiology (Bethesda, Md. : 1985)》1981,50(5):1098-1103
A system of instrumentation for continuous measurement of gaseous metabolism and minute volume (VI) in the human newborn is described. O2 uptake and CO2 production are measured by open-circuit techniques utilizing a Servomex OA184 differential paramagnetic O2 analyzer and a BEckman LB-2 infrared CO2 analyzer. VI is measured with bias-flow pneumotachometry. Bench performance is described, methodological errors are defined, and clinical data are presented. The instrumentation is capable of safe, accurate, and continuous measurement of respiratory and metabolic variables in low-birth-weight infants. 相似文献
4.
IL-12, but not IL-18, is critical to neutrophil activation and resistance to polymicrobial sepsis induced by cecal ligation and puncture 总被引:2,自引:0,他引:2
Moreno SE Alves-Filho JC Alfaya TM da Silva JS Ferreira SH Liew FY 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(5):3218-3224
Sepsis is a systemic inflammatory response resulting from local infection due, at least in part, to impaired neutrophil migration. IL-12 and IL-18 play an important role in neutrophil migration. We have investigated the mechanism and relative role of IL-12 and IL-18 in polymicrobial sepsis induced by cecal ligation and puncture (CLP) in mice. Wild-type (WT) and IL-18(-/-) mice were resistant to sublethal CLP (SL-CLP) sepsis. In contrast, IL-12(-/-) mice were susceptible to SL-CLP sepsis with high bacteria load in peritoneal cavity and systemic inflammation (serum TNF-alpha and lung neutrophil infiltration). The magnitude of these events was similar to those observed in WT mice with lethal CLP sepsis. The inability of IL-12(-/-) mice to restrict the infection was not due to impairment of neutrophil migration, but correlated with decrease of phagocytosis, NO production, and microbicidal activities of their neutrophils, and with reduction of systemic IFN-gamma synthesis. Consistent with this observation, IFN-gamma(-/-) mice were as susceptible to SL-CLP as IL-12(-/-) mice. Moreover, addition of IFN-gamma to cultures of neutrophils from IL-12(-/-) mice restored their phagocytic, microbicidal activities and NO production. Mortality of IL-12(-/-) mice to SL-CLP was prevented by treatment with IFN-gamma. Thus we show that IL-12, but not IL-18, is critical to an efficient host defense in polymicrobial sepsis. IL-12 acts through induction of IFN-gamma and stimulation of phagocytic and microbicidal activities of neutrophils, rather than neutrophil migration per se. Our data therefore provide further insight into the defense mechanism against this critical area of infectious disease. 相似文献
5.
Olga Malinkiewicz Thais Grancha Agustin Molina‐Ontoria Alejandra Soriano Hicham Brine Henk J. Bolink 《Liver Transplantation》2013,3(4):472-477
Simple bilayer solar cells, using commercially available cationic cyanine dyes as donors and evaporated C60 layer as an acceptor are prepared. Cyanine dyes with absorption maxima of 578, 615 and 697 nm having either perchlorate or hexafluorophosphate counter‐ions are evaluated. The perchlorate dye leads to cells with S‐shape current‐voltage curves; only the dyes with the hexafluorophosphate counter‐ions lead to efficient solar cells. When the wide bandgap dyes are employed, S‐shape current‐voltage curves are obtained when the conductive polymer PEDOT:PSS is used as hole transport layer. Substitution of PEDOT:PSS with MoO3 leads to cells with more rectangular current–voltage curves and high fill factors. Additionally, the cells using the MoO3 layer for hole extraction lead to high open circuit voltages of 0.9 V. In the case that a low bandgap hexafluorophosphate dye is used with the HOMO above that of the PEDOT:PSS the cell performance is independent on the type of hole transport layer employed. Using this approach, bilayer solar cells are obtained with power efficiencies ranging from 1.8 to 2.9% depending on the particular dye employed. These are impressive numbers for bilayer solar cell that are partially solution processed in ambient conditions. 相似文献
6.
Daniela Josa Elaine F.F. da Cunha Teodorico C. Ramalho Thais C.S. Souza Melissa S. Caetano 《Journal of biomolecular structure & dynamics》2013,31(4):373-376
Abstract Rifamicyns (Rifs) are antibiotic widely used for the treatment of tuberculosis (TB); nevertheless, their efficacy has been limited by a high percentage of mutations, principally in the rpoB gene. In this work, the first three-dimensional molecular model of the hypothetical structures for the wild-type and D516V and H526L mutants of Mycobacterium tuberculosis (mtRNAP) were elucidated by a homology modeling method. In addition, the orientations and binding affinities of some Rifs with those new structures were investigated. Our findings could be helpful for the design of new more potent rifamycin analogs. 相似文献
7.
Thais B. Bittar Yajuan Lin Lara R. Sassano Benjamin J. Wheeler Susan L. Brown William P. Cochlan Zackary I. Johnson 《Journal of phycology》2013,49(3):523-535
Marine phytoplankton have conserved elemental stoichiometry, but there can be significant deviations from this Redfield ratio. Moreover, phytoplankton allocate reduced carbon (C) to different biochemical pools based on nutritional status and light availability, adding complexity to this relationship. This allocation influences physiology, ecology, and biogeochemistry. Here, we present results on the physiological and biochemical properties of two evolutionarily distinct model marine phytoplankton, a diatom (cf. Staurosira sp. Ehrenberg) and a chlorophyte (Chlorella sp. M. Beijerinck) grown under light and nitrogen resource gradients to characterize how carbon is allocated under different energy and substrate conditions. We found that nitrogen (N)‐replete growth rate increased monotonically with light until it reached a threshold intensity (~200 μmol photons · m?2 · s?1). For Chlorella sp., the nitrogen quota (pg · μm?3) was greatest below this threshold, beyond which it was reduced by the effect of N‐stress, while for Staurosira sp. there was no trend. Both species maintained constant maximum quantum yield of photosynthesis (mol C · mol photons?1) over the range of light and N‐gradients studied (although each species used different photophysiological strategies). In both species, C:chl a (g · g?1) increased as a function of light and N‐stress, while C:N (mol · mol?1) and relative neutral lipid:C (rel. lipid · g?1) were most strongly influenced by N‐stress above the threshold light intensity. These results demonstrated that the interaction of substrate (N‐availability) and energy gradients influenced C‐allocation, and that general patterns of biochemical responses may be conserved among phytoplankton; they provided a framework for predicting phytoplankton biochemical composition in ecological, biogeochemical, or biotechnological applications. 相似文献
8.
Gleice Cristina Leite Maura Salaroli Oliveira Lauro Vieira Perdig?o-Neto Cristiana Kamia Dias Rocha Thais Guimar?es Camila Rizek Anna Sara Levin Silvia Figueiredo Costa 《PloS one》2016,11(3)
The study investigated the effect of antibiotic combinations against 20 clinical isolates of A. baumannii (seven colistin-resistant and 13 colistin-susceptible) with different resistance mechanisms. Clinical data, treatment, and patient mortality were evaluated. The following methods were used: MIC, PCRs, and outer membrane protein (OMP) analysis. Synergy was investigated using the checkerboard and time-kill methods. Clonality was evaluated by PFGE. Based on clonality, the whole genome sequence of six A. baumannii isolates was analyzed. All isolates were resistant to meropenem, rifampicin, and fosfomycin. OXA-23 and OXA-143 were the most frequent carbapenemases found. Four isolates showed loss of a 43kDa OMP. The colistin-susceptible isolates belonged to different clones and showed the highest synergistic effect with fosfomycin-amikacin. Among colistin-resistant isolates, the highest synergistic effect was observed with the combinations of colistin-rifampicin followed by colistin-vancomycin. All colistin-resistant isolates harbored blaOXA-23-like and belonged to CC113. Clinical and demographic data were available for 18 of 20 patients. Fourteen received treatment and eight patients died during treatment. The most frequent site of infection was the blood in 13 of 14 patients. Seven patients received vancomycin plus an active drug against A. baumannii; however, mortality did not differ in this group. The synergistic effect was similar for colistin-susceptible isolates of distinct clonal origin presenting with the same resistance mechanism. Overall mortality and death during treatment was high, and despite the high synergism in vitro with vancomycin, death did not differ comparing the use or not of vancomycin plus an active drug against A. baumannii. 相似文献
9.
Thais Maia Torres Priscila Silva de Almeida-Monteiro Renata Vieira do Nascimento Vanessa Alves Pereira Yasmim Maia Ferreira Jessica Sales Lobato Romulo Roberto Ribeiro Pinheiro Yara Silvino Sales Assis Rubens Montenegro Carminda Sandra Brito Salmito-Vanderley 《Animal Reproduction》2022,19(1)
The action of substances with non-permeable cryoprotectant potential, besides glucose, has not yet been studied for the species Prochilodus brevis. The objective of this work was to evaluate the action of four non-permeable cryoprotectants on this species sperm cryopreservation. Five pools were cryopreserved in a solution of 5% glucose and 10% dimethyl sulfoxide (Me2SO) associated or not (control) with cryoprotectants egg yolk (5, 10 or 12%), soy lecithin (2.5, 7.5 or 10%), sucrose (5, 10 or 20%) and lactose (5, 8 or 15%). After thawing, samples were evaluated for sperm kinetics (total motility, motility duration, velocities, and wobble - WOB), morphology and membrane and DNA integrity. The treatments containing egg yolk improved significantly (P<0.05) results when compared the control for the membrane integrity parameter. When compared to other treatments, egg yolk, at any concentration, presented higher results (P<0.05) for membrane integrity, total motility, curvilinear velocity (VCL) and average path velocity (VAP) parameters. Egg yolk also showed the best results for WOB, but it did not differ from 5% and 8% lactose and 5% and 20% sucrose. Soy lecithin had the lowest percentages of morphologically normal sperm (P<0.05), while the other treatments did not differ from each other. There was no difference regarding DNA integrity data. Thus, 5% egg yolk is indicated as a non-permeable cryoprotectant for P. brevis, in association with 5% glucose and 10% Me2SO. 相似文献
10.
Thais R. Peclat Katie L. Thompson Gina M. Warner Claudia C.S. Chini Mariana
G. Tarrag Delaram Z. Mazdeh Chunlian Zhang Jose ZavalaSolorio Ganesh Kolumam Yao Liang Wong Robert L. Cohen Eduardo N. Chini 《Aging cell》2022,21(4)
Nicotinamide adenine dinucleotide (NAD) levels decline during aging, contributing to physical and metabolic dysfunction. The NADase CD38 plays a key role in age‐related NAD decline. Whether the inhibition of CD38 increases lifespan is not known. Here, we show that the CD38 inhibitor 78c increases lifespan and healthspan of naturally aged mice. In addition to a 10% increase in median survival, 78c improved exercise performance, endurance, and metabolic function in mice. The effects of 78c were different between sexes. Our study is the first to investigate the effect of CD38 inhibition in naturally aged animals. 相似文献