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941.
Glushakova A. M. Lysak L. V. Kachalkin A. V. Ivanova A. E. Umarova A. B. Abramyan I. A. Ezhelev Z. S. Maksimova I. A. 《Microbiology》2021,90(2):176-186
Microbiology - In a model experiment, the transformation of microbial complexes of cultivated saprotrophic bacteria and yeasts during freezing-thawing was studied in various natural substrates that... 相似文献
942.
Kaminsky V. V. Emelyanenko A. M. Aleshkin A. V. Emelyanenko K. A. Boinovich L. B. 《Microbiology》2021,90(5):643-646
Microbiology - The surface of the MA8 magnesium alloy, modified by laser treatment, was found to acquire superhydrophilic properties and high bactericidal activity against Escherichia coli K12... 相似文献
943.
Baikenova M. B. Chereshnev V. A. Sokolova K. V. Gette I. F. Emelyanov V. V. Danilova I. G. 《Journal of Evolutionary Biochemistry and Physiology》2021,57(4):772-781
Journal of Evolutionary Biochemistry and Physiology - Due to a high occurrence of diabetes mellitus (DM) and its complications, insulin-positive cells detected in different organs are of great... 相似文献
944.
Kolomeyets N. L. Syslonova O. V. Smirnova S. L. Peshkin E. A. Roshchevskaya I. M. 《Journal of Evolutionary Biochemistry and Physiology》2021,57(6):1351-1362
Journal of Evolutionary Biochemistry and Physiology - Changes in bioelectrical impedance of the myocardium and liver were revealed in male Wistar rats chronically exposed to doxorubicin.... 相似文献
945.
Jin Wei Mia Madel Alfajaro Peter C. DeWeirdt Ruth E. Hanna William J. Lu-Culligan Wesley L. Cai Madison S. Strine Shang-Min Zhang Vincent R. Graziano Cameron O. Schmitz Jennifer S. Chen Madeleine C. Mankowski Renata B. Filler Neal G. Ravindra Victor Gasque Fernando J. de Miguel Ajinkya Patil Huacui Chen Craig B. Wilen 《Cell》2021,184(1):76-91.e13
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946.
Amanda Tetlock Christopher K. Yost John Stavrinides Richard G. Manzon 《Applied and environmental microbiology》2012,78(21):7638-7644
Vertebrate metamorphosis is often marked by dramatic morphological and physiological changes of the alimentary tract, along with major shifts in diet following development from larva to adult. Little is known about how these developmental changes impact the gut microbiome of the host organism. The metamorphosis of the sea lamprey (Petromyzon marinus) from a sedentary filter-feeding larva to a free-swimming sanguivorous parasite is characterized by major physiological and morphological changes to all organ systems. The transformation of the alimentary canal includes closure of the larval esophagus and the physical isolation of the pharynx from the remainder of the gut, which results in a nonfeeding period that can last up to 8 months. To determine how the gut microbiome is affected by metamorphosis, the microbial communities of feeding and nonfeeding larval and parasitic sea lamprey were surveyed using both culture-dependent and -independent methods. Our results show that the gut of the filter-feeding larva contains a greater diversity of bacteria than that of the blood-feeding parasite, with the parasite gut being dominated by Aeromonas and, to a lesser extent, Citrobacter and Shewanella. Phylogenetic analysis of the culturable Aeromonas from both the larval and parasitic gut revealed that at least five distinct species were represented. Phenotypic characterization of these isolates revealed that over half were capable of sheep red blood cell hemolysis, but all were capable of trout red blood cell hemolysis. This suggests that the enrichment of Aeromonas that accompanies metamorphosis is likely related to the sanguivorous lifestyle of the parasitic sea lamprey. 相似文献
947.
Charles L. Nunn Peter H. Thrall Kelly Stewart Alexander H. Harcourt 《Evolutionary ecology》2008,22(4):519-543
Emerging infectious diseases threaten a wide diversity of animals, and important questions remain concerning disease emergence
in socially structured populations. We developed a spatially explicit simulation model to investigate whether—and under what
conditions—disease-related mortality can impact rates of pathogen spread in populations of polygynous groups. Specifically,
we investigated whether pathogen-mediated dispersal (PMD) can occur when females disperse after the resident male dies from
disease, thus carrying infections to new groups. We also examined the effects of incubation period and virulence, host mortality
and rates of background dispersal, and we used the model to investigate the spread of the virus responsible for Ebola hemorrhagic
fever, which currently is devastating African ape populations. Output was analyzed using regression trees, which enable exploration
of hierarchical and non-linear relationships. Analyses revealed that the incidence of disease in single-male (polygynous)
groups was significantly greater for those groups containing an average of more than six females, while the total number of
infected hosts in the population was most sensitive to the number of females per group. Thus, as expected, PMD occurs in polygynous
groups and its effects increase as harem size (the number of females) increases. Simulation output further indicated that
population-level effects of Ebola are likely to differ among multi-male–multi-female chimpanzees and polygynous gorillas,
with larger overall numbers of chimpanzees infected, but more gorilla groups becoming infected due to increased dispersal
when the resident male dies. Collectively, our results highlight the importance of social system on the spread of disease
in wild mammals. 相似文献
948.
Titrating the effects of mitochondrial complex I impairment in the cell physiology. 总被引:14,自引:0,他引:14
The mitochondrial oxidative phosphorylation system consists of five multimeric enzymes (complexes I-V). NADH dehydrogenase or complex I (CI) is affected in most of the mitochondrial diseases and in some neurodegenerative disorders. We have studied the physiological consequences of a partial CI inhibition at the cellular level. We used a genetic model (40% CI-inhibited human-ape xenomitochondrial cybrids) and a drug-induced model (0-100% CI-inhibited cells using different concentrations of rotenone). We observed a quantitative correlation between the level of CI impairment and cell respiration, cell growth, free radical production, lipid peroxidation, mitochondrial membrane potential, and apoptosis. We showed that cell death was quantitatively associated with free radical production rather than with a decrease in respiratory chain function. The results obtained with human xenomitochondrial cybrid cells were compatible with those observed in rotenone-induced 40% CI-inhibited cells. At high concentrations (5-6-fold higher than the concentration necessary for 100% CI inhibition), rotenone showed a second toxic effect at the level of microtubule assembly, which also led to apoptosis. The correlation found among all the parameters studied helped clarify the physiological consequences of partial CI inhibitions at the cellular level. 相似文献
949.
Epitope analysis and molecular modeling reveal the topography of the C-terminal peptide of the beta-subunit of human chorionic gonadotropin. 总被引:2,自引:0,他引:2
N Venkatesh S Krishnaswamy S Meuris G S Murthy 《European journal of biochemistry》1999,265(3):1061-1066
Human chorionic gonadotropin (hCG) belongs to a family of heterodimeric glycoprotein hormones that share a common alpha-subunit and a hormone-specific beta-subunit. Among the gonadotropin beta-subunits, greater than 85% homology exists between lutropin (hLH)beta and hCGbeta in their first 114 amino acid residues. However, unlike hLHbeta, hCGbeta contains a 31-amino acid hydrophilic stretch at its carboxyl end (CTPbeta: C-terminal peptide). Although the crystal structure of deglycosylated hCG has been solved, the topography of CTPbeta remains unknown. In this study, we have attempted to define the topology of CTPbeta using mAb probes. We investigated three epitopes on hCGalpha, which are hidden in the hCGalphabeta dimer. However, these epitopes are not hidden in hLH, which has a similar subunit interface to that of hCG, but lacks CTPbeta. This suggested that these epitopes are not masked at the subunit interface of hLH or hCG. Hence, we hypothesized that, in the case of hCG, these epitopes are masked by the CTPbeta. Consistent with this view, several treatments of hCG that removed CTPbeta unmasked these epitopes and enhanced their reactivity with the corresponding mAbs. In order to localise the position of CTPbeta on the alpha-subunit, we used an epitope-mapping strategy [N. Venkatesh & G. S. Murthy (1997) J. Immunol. Methods 202, 173-182] based on differential susceptibility of epitopes to covalent modifications. This enabled us to predict the possible topography of CTPbeta. Further, we were also able to build a model of CTPbeta, completely independently of the epitope-mapping studies, using a homology-based modeling approach [S. Krishnaswamy, I. Lakshminarayanan & S. Bhattacharya (1995) Protein Sci. 4 (Suppl. 2), 86-97]. Results obtained from these two different approaches (epitope analysis and homology modeling) agree with each other and indicate that portions of CTPbeta are in contact with hCGalpha in the native hCG dimer. 相似文献
950.
The management of chronic viral hepatitis C is evolving rapidly. Monotherapy with interferon, the accepted standard of treatment until recently, achieves only a modest sustained virological response rate of 15%. Combination treatment with alpha-2b interferon and ribavirin has been shown to increase sustained response rates to 40% in patients who have never been treated with interferon and to 50% in those who have relapsed following monotherapy with interferon. However, side effects, which have led to the discontinuation of combination treatment in a significant proportion of patients, must be carefully monitored. Treatment with interferon alpha-2b and ribavirin has now been approved in Canada, but the selection and monitoring of patients suitable for combination treatment requires special expertise. Although improvements in current therapeutic options may be possible with more frequent, higher doses or long-acting forms of interferon together with ribavirin, low sustained response rates (i.e., below 30%) for patients with hepatitis C virus genotype 1 emphasize the need for novel antiviral medications that will target the functional sites of the HCV genome. 相似文献