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71.
Four antimicrobial peptides were purified from Royal Jelly of honeybees, by using reverse phase-HPLC and sequenced by using Q-Tof-MS/MS: PFKLSLHL-NH(2) (Jelleine-I), TPFKLSLHL-NH(2) (Jelleine-II), EPFKLSLHL-NH(2) (Jelleine-III), and TPFKLSLH-NH(2) (Jelleine-IV). The peptides were synthesized on-solid phase, purified and submitted to different biological assays: antimicrobial activity, mast cell degranulating activity and hemolysis. The Jelleines-I-III presented exclusively antimicrobial activities against yeast, Gram+ and Gram- bacteria; meanwhile, Jelleine-IV was not active in none of the assays performed. These peptides do not present any similarity with the other antimicrobial peptides from the honeybees; they are produced constitutively by the workers and secreted into Royal Jelly.  相似文献   
72.
Autophagy is a process by which cytoplasmic material is sequestered in a double-membrane vesicle destined for degradation. Nutrient deprivation stimulates the pathway and the number of autophagosomes in the cell increases in response to such stimulus. In the current report we have demonstrated that actin is necessary for starvation-mediated autophagy. When the actin cytoskeleton is depolymerized, the increase in autophagic vacuoles in response to the starvation stimulus was abolished without affecting maturation of remaining autophagosomes. In addition, actin filaments colocalized with ATG14, BECN1/Beclin1 and PtdIns3P-rich structures, and some of them have a typical omegasome shape stained with the double FYVE domain or ZFYVE1/DFCP1. In contrast, no major colocalization between actin and ULK1, ULK2, ATG5 or MAP1LC3/LC3 was observed. Taken together, our data indicate that actin has a role at very early stages of autophagosome formation linked to the PtdIns3P generation step. In addition, we have found that two members of the Rho family of proteins, RHOA and RAC1 have a regulatory function on starvation-mediated autophagy, but with opposite roles. Indeed, RHOA has an activatory role whereas Rac has an inhibitory one. We have also found that inhibition of the RHOA effector ROCK impaired the starvation-mediated autophagic response. We propose that actin participates in the initial membrane remodeling stage when cells require an enhanced rate of autophagosome formation, and this actin function would be tightly regulated by different members of the Rho family.  相似文献   
73.
How do biogeographically different provinces arise in response to oceanic barriers to dispersal? Here, we analyse how traits related to the pelagic dispersal and adult biology of 985 tropical reef fish species correlate with their establishing populations on both sides of two Atlantic marine barriers: the Mid-Atlantic Barrier (MAB) and the Amazon–Orinoco Plume (AOP). Generalized linear mixed-effects models indicate that predictors for successful barrier crossing are the ability to raft with flotsam for the deep-water MAB, non-reef habitat usage for the freshwater and sediment-rich AOP, and large adult-size and large latitudinal-range for both barriers. Variation in larval-development mode, often thought to be broadly related to larval-dispersal potential, is not a significant predictor in either case. Many more species of greater taxonomic diversity cross the AOP than the MAB. Rafters readily cross both barriers but represent a much smaller proportion of AOP crossers than MAB crossers. Successful establishment after crossing both barriers may be facilitated by broad environmental tolerance associated with large body size and wide latitudinal-range. These results highlight the need to look beyond larval-dispersal potential and assess adult-biology traits when assessing determinants of successful movements across marine barriers.  相似文献   
74.
The glycolytic proteins in plants are coded by small multigene families, which provide an interesting contrast to the high copy number of gene families studied to date. The alcohol dehydrogenase (Adh) genes encode glycolytic enzymes that have been characterized in some plant families. Although the amino acid sequences of zinc-containing long-chain ADHs are highly conserved, the metabolic function of this enzyme is variable. They also have different patterns of expression and are submitted to differences in nonsynonymous substitution rates between gene copies. It is possible that the Adh copies have been retained as a consequence of adaptative amino acid replacements which have conferred subtle changes in function. Phylogenetic analysis indicates that there have been a number of separate duplication events within angiosperms, and that genes labeled Adh1, Adh2 and Adh3 in different groups may not be homologous. Nonsynonymous/synonymous ratios yielded no signs of positive selection. However, the coefficients of functional divergence (theta) estimated between the Adh1 and Adh2 gene groups indicate statistically significant site-specific shift of evolutionary rates between them, as well as between those of different botanical families, suggesting that altered functional constraints may have taken place at some amino acid residues after their diversification. The theoretical three-dimensional structure of the alcohol dehydrogenase from Arabis blepharophylla was constructed and verified to be stereochemically valid.  相似文献   
75.
Coral Reefs - Climate change is causing the distribution and abundance of many organisms to change. In particular, organisms typical of the tropics are increasing in abundance in many subtropical...  相似文献   
76.

Introduction

The growing number of renal transplant recipients in a sustained immunosuppressive state is a factor that can contribute to increased incidence of sepsis. However, relatively little is known about sepsis in this population. The aim of this single-center study was to evaluate the factors associated with hospital mortality in renal transplant patients admitted to the intensive care unit (ICU) with severe sepsis and septic shock.

Methods

Patient demographics and transplant-related and ICU stay data were retrospectively collected. Multiple logistic regression was conducted to identify the independent risk factors associated with hospital mortality.

Results

A total of 190 patients were enrolled, 64.2% of whom received kidneys from deceased donors. The mean patient age was 51±13 years (males, 115 [60.5%]), and the median APACHE II was 20 (16–23). The majority of patients developed sepsis late after the renal transplantation (2.1 [0.6–2.3] years). The lung was the most common infection site (59.5%). Upon ICU admission, 16.4% of the patients had ≤1 systemic inflammatory response syndrome criteria. Among the patients, 61.5% presented with ≥2 organ failures at admission, and 27.9% experienced septic shock within the first 24 hours of ICU admission. The overall hospital mortality rate was 38.4%. In the multivariate analysis, the independent determinants of hospital mortality were male gender (OR = 5.9; 95% CI, 1.7–19.6; p = 0.004), delta SOFA 24 h (OR = 1.7; 95% CI, 1.2–2.3; p = 0.001), mechanical ventilation (OR = 30; 95% CI, 8.8–102.2; p<0.0001), hematologic dysfunction (OR = 6.8; 95% CI, 2.0–22.6; p = 0.002), admission from the ward (OR = 3.4; 95% CI, 1.2–9.7; p = 0.02) and acute kidney injury stage 3 (OR = 5.7; 95% CI,1.9–16.6; p = 0.002).

Conclusions

Hospital mortality in renal transplant patients with severe sepsis and septic shock was associated with male gender, admission from the wards, worse SOFA scores on the first day and the presence of hematologic dysfunction, mechanical ventilation or advanced graft dysfunction.  相似文献   
77.
This study aimed to quantify verbascoside (VEB), perform molecular docking studies of VEB with the α-glucosidase (GL) of Bacillus stearothermophilus, and evaluate the inhibition of the enzyme by L. dulcis preparations. The substrate concentration and presence of reduced glutathione were evaluated for their effect on the in vitro inhibition of the GL enzyme. Assays were also performed in the presence and absence of simulated gastric fluid. The antidiabetic fractions 2 and 3 were the most inhibited GL, but their activity were significantly decreased in the presence of gastric fluid. Chromatographic analyses confirmed the predominant presence of VEB in the samples. The samples had VEB concentrations between 49.9 and 243.5 mg/g. Simulation of the molecular docking of VEB were consistent with its GL-inhibitory activity. It can conclude that the crude ethanol extract and fractions show inhibitory activity against the GL enzyme.  相似文献   
78.
Brood protection is a common feature of marine bivalves from higher latitudes. In this study the pallial organs of the Antarctic bivalves, Mysella charcoti (Lamy, 1906) and M. narchii Passos & Domaneschi, 2006 were investigated with respect to anatomical characters related to brooding. Both species are simultaneous hermaphrodites and their eggs contain a large amount of yolk. The number of broods ranges from 16 to 30 in M. narchii and 7–27 in M. charcoti, and ovoviviparity was observed for both. Their ctenidia differ in structure, those of M. charcoti being simpler. In M. narchii there is a large elasticity of the tissue of the marginal food grooves of ctenidia, and cilia are much more abundant on the ctenidial abfrontal surface and on the visceral mass epithelium than in M. charcoti. Anatomical characters of M. charcoti can be considered derived when compared to those of M. narchii. In conclusion, detailed anatomical characters related to brooding may be useful in future systematic studies of Antarctic Bivalvia.  相似文献   
79.
Molecular Biology Reports - Hepatocellular carcinoma is one of the most common types of cancer in the world with high mortality rate and new therapies that control of fatty acid metabolism may...  相似文献   
80.
In Vitro Cellular & Developmental Biology - Plant - Plants of the Verbenaceae family are well known for having constituents with important bioactive properties. The objective of this study was...  相似文献   
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