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441.
Yitian Zheng MD Binhao Shi MD Mengqing Ma MD Xiaoqin Wu PhD Xianhe Lin MD PhD 《Journal of cellular physiology》2019,234(5):5488-5495
Class III histone deacetylases (HDACs) belong to the proteasome family, comprising seven family members identified in mammalian cells, identified Sirt1–Sirt7. As an important member of HDACs, Sirt3 is hotly debated for its multiple functions. It was reported that Sirt3 got involved in the alleviation of multiple diseases, including myocardial infarction, neuron ischemia, hypertrophy, and diabetic myopathy. Through regulating many cellular mechanisms, such as apoptosis, autophagy, and clearance of reactive oxygen species (ROS), Sirt3 played an important role in the alleviation of myocardial ischemia–reperfusion injury. Nowadays Sirt3-induced autophagy was indicated to be involved in the process of the development of myocardial ischemia–reperfusion injury. Sirt3 could both activate and inhibit autophagy process by activating different downstream signal pathways, such as Sirt3–AMP-activated protein kinase pathway, Sirt3–Foxo3a pathway, and Sirt3–superoxide dismutase–mitochondrial ROS pathway. Whereas the Sirt3-induced autophagy in different phases of myocardial ischemia–reperfusion has not been systematically illustrated. In this review, we summarized the regulated mechanisms found in these years and listed the updated research about the relationship between Sirt3 and autophagy which are both positive and negative during myocardial ischemia–reperfusion phase. We anticipated that we may controlled the activation of autophagy by regulating the concentration of Sirt3 in myocyte. By maintaining a proper expression of autophagy in different phases of myocardial ischemia–reperfusion, we could reduce the morbidity of patients with myocardial infarction apparently in the future. 相似文献
442.
A case of mycetoma, with abscess-like lesions which appeared on the right forearm of a 43-year-old male, is briefly reported. A few whitish granules were detected in the oily-like discharge, the same as in the histologic examination. No bone involvement was discovered in X-ray examination. Actinomadura was identified in the culture. A daily dose of 4 g bactrin brought significant improvement to the patients continuing the treatment. 相似文献
443.
Hao Zhang MD Yang Gao MD Yiming Wang MD Yi Yan MD Zhijian Yang MD PHD Dengshun Miao PHD Dingguo Zhang MD PHD 《Journal of cellular biochemistry》2019,120(9):14745-14755
It is known that parathyroid hormone-related peptide (PTHrP) contains a nuclear localization sequence (NLS, 87-107), which, together with its C-terminus (107-139), has been shown to positively regulate vascular smooth muscle cell (VSMCs) proliferation and vascular neointima formation, and inhibit cellular apoptosis. The role of PTHrP in ischemic cardiac diseases remains unclear. In this study, we attempted to determine whether PTHrP 87 to 139 can play a role in promoting cardiac function via enhancing angiogenesis after myocardial infarction (MI) occurred. MI was reproduced in C57BL/6 mice using a coronary artery ligation method. In total, three groups (n = 11 per group) of animals were used, and they were received either PTHrP 87 to 139 (80 µg/kg, treatment group) or saline (MI and Sham group) subcutaneously once a day for 4 weeks after MI. To measure cardiac function, an echocardiography was generated and cardiac tissue was harvested for immunohistological studies 4 weeks after operation. Our results show that, after MI, the cardiac function of the experimental mice was significantly impaired. PTHrP 87 to 139 treatment attenuated cardiac dysfunction in MI mice. Besides, as indicated by decreased heart weight/body weight and lung weight/body weight ratio, PTHrP 87 to 139 attenuated pulmonary congestion and cardiac hypertrophy. Masson staining revealed that PTHrP 87 to 139 attenuated myocardial fibrosis after MI. Also, terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling staining and the expression of cleaved caspase 3 suggested that MI-induced myocytes apotosis was inhibited by PTHrP 87 to 139. In addition to the significantly increased capillary density, PTHrP 87 to 139 treatment also induced p-Akt and several angiogenic factors. In conclusion, PTHrP 87 to 139 treatment preserved cardiac function after MI, and stimulated angiogenesis via upregulating vascular endothelial growth factor and basic fibroblast growth factor (bFGF) in infarct border zone of ischemic myocardium,. These results suggest that PTHrP 87 to 139 is of therapeutic potential for MI. 相似文献
444.
Abstract. Rates and directions of change over a 20-yr interval in five long-unburned (> 60 yr) plant communities were studied using multivariate analyses and compositional vectors. The study sites were located in fire and summer-drought adapted, xerophytic vegetation with many endemics on acidic, nutrient-poor, sandy soils in south-central peninsular Florida. Sizes of individual stems from 72 sets of nested permanent quadrats were measured in 1969, 1979, and 1989. Patterns of vegetation change differed by community. Flatwood and bayhead quadrats showed rapid increases in densities and basal areas of Persea borbonia (red bay). In the southern ridge sandhill community, evergreen clonal Quercus species (oaks) and Pinus clausa (sand pine) increased in dominance and grasses declined. Oaks (especially Q. geminata) also increased in importance in scrubby flatwoods. Sand pine scrub was relatively stable in composition, but experienced marked structural changes due to substantial sand pine mortality (18% during 1969–1979, 39% during 1979–1989). Compositional changes in the absence of fire were greatest whereas structural changes were least in southern ridge sandhill and scrubby flatwoods, both communities which normally receive frequent, recurrent fire. Compositional changes were lowest in sand pine scrub, which is normally infrequently burned. Classic successional patterns such as species replacement, decreases in density, and increases in basal area were generally lacking. Tree densities increased in two of four community types (southern ridge sandhill, scrubby flatwoods); while basal area declined in the flatwoods/bayhead and sand pine scrub sites. Directions of compositional vectors included divergent, opposing, and complex patterns, suggesting vegetation change in the absence of fire has a strong stochastic component. 相似文献
445.
Suzette D. Tardif Cashell E. Jaquish Robert L. Toal Donna G. Layne Rachel A. Power 《Journal of medical primatology》1998,27(1):28-32
This report compares estimated gestational ages from published cubic spline curves to gestational ages estimated retrospectively from delivery dates in 28 pregnancies from ten common marmosets (Callithrix jacchus). Both CRL- and BPD-based estimates of gestational age were closely correlated with delivery-based gestational age estimates. Of the three ultrasound machines used, the one with 16 shades of gray and a sequential linear array overestimated gestational age during early pregnancy, based on CRL measures. Measures from the other two machines (64 or 264 shades of gray; linear sector and annular array or electronic phase array) were similar and resulted in a correlation of the two estimates of gestational age of 0.94 and a mean difference between the two estimates of 0.16 days with 80% of CRL-based gestational age estimates being within ± 5 days of the delivery-based estimate. The reliability of BPD-based estimates of gestational age was strongly related to pregnancy outcome. BPD-based estimates underestimated gestational age in poor outcome pregnancies (i.e., those in which infants died within 7 days of birth) but not in good outcome pregnancies. The combined CRL- and BPD-based estimates on poor outcome pregnancies suggest that there was less growth in BPD in late gestation for those pregnancies that resulted in nonviable offspring. For good outcome pregnancies, the correlation between BPD-based and delivery-based estimates of gestational age was 0.871 and the mean difference between the two estimates was ?0.06 days with 83.3% of BPD-based estimates falling within ± 5 days of delivery-based estimates. 相似文献
446.
447.
448.
William B. Collins Bruce W. Dale Layne G. Adams Darien E. Mcelwain Kyle Joly 《The Journal of wildlife management》2011,75(2):369-377
In the early 1990s the Nelchina Caribou (Rangifer tarandus) Herd (NCH) began a dramatic shift to its current winter range, migrating at least an additional 100 km beyond its historic range. We evaluated the impacts of fire and grazing history on lichen abundance and subsequent use and distribution by the NCH. Historic (prior to 1990) and current (2002) winter ranges of the NCH had similar vascular vegetation, lichen cover (P = 0.491), and fire histories (P = 0.535), but the former range had significantly less forage lichen biomass as a result of grazing by caribou. Biomass of forage lichens was twice as great overall (P = 0.031) and 4 times greater in caribou selected sites on the current range than in the historic range, greatly increasing availability to caribou. Caribou on the current range selected for stands with >20% lichen cover (P < 0.001), greater than 1,250 kg/ha (P < 0.001) forage lichen biomass and stands older than 80 yr postfire (P < 0.001). After fires, forage lichen cover and biomass seldom recovered sufficiently to attract caribou grazing until after ≥60 yr, and, as a group, primary forage lichen species did not reach maximum abundance until 180 yr postfire. Recovery following overgrazing can occur much more quickly because lichen cover, albeit mostly fragments, and organic substrates remain present. Our results provide benchmarks for wildlife managers assessing condition of caribou winter range and predicting effects of fires on lichen abundance and caribou distribution. Of our measurements of cover and biomass by species, densities and heights of trees, elevation, slope and aspect, only percentage cover by Cladonia amaurocraea, Cladina rangiferina, Flavocetraria cuculata, and lowbush cranberry (Vaccinium vitis-idaea) were necessary for predicting caribou use of winter range. © 2011 The Wildlife Society 相似文献
449.
Heather E. Johnson Trevor S. Golden Layne G. Adams David D. Gustine Elizabeth A. Lenart 《The Journal of wildlife management》2020,84(3):401-412
Increasing demands for energy have generated interest in expanding oil and gas production on the North Slope of Alaska, USA, raising questions about the resilience of barren-ground caribou (Rangifer tarandus) populations to new development. Although the amount of habitat lost directly to energy development in the Arctic will likely be relatively small, there are significant concerns about habitat that may be indirectly affected because of caribou avoidance behaviors. Behavioral responses to energy development for wildlife have been documented, but such responses are often assumed to dissipate over time, despite scant information on the ability of animals to habituate. To understand the long-term effects of energy development on barren-ground caribou, we investigated the behavior of the Central Arctic Herd in northern Alaska, which has been exposed to oil development on its summer range for approximately 40 years. Using recent (2015–2017) location data from global positioning system (GPS)-collared females, we conducted a zone of influence analysis to assess whether caribou reduced their use of habitat near energy development, and if so, the distance the effects attenuated. We conducted this analysis for the calving, post-calving, and mosquito harassment periods when caribou exhibit distinct resource selection patterns, and contrasted our results to past research that investigated the responses of the Central Arctic Herd immediately following the construction of the oil fields. Despite the long-term presence of energy development within the Central Arctic Herd summer range, we found that female caribou exhibited avoidance responses to infrastructure during all time periods, although the effects waned across the summer. Caribou reduced their use of habitat within 5 km of development during the calving period, within 2 km during the post-calving period, and within 1 km during the mosquito harassment period; these areas were predicted to overlap 12%, 15%, and 17% of important calving, post-calving, and mosquito period habitat, respectively. During the calving period, the indirect effects we observed were similar to those observed in past research, whereas during the post-calving and mosquito periods, we detected avoidance responses that had not been previously reported. These findings corroborate a growing body of evidence suggesting that habituation to industrial development in caribou in the Arctic is likely to be weak or absent, and emphasizes the value of minimizing the footprint of infrastructure within important seasonal habitat to reduce behavioral effects to barren-ground caribou. © 2019 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. 相似文献
450.
Extrachromosomal Nature of Hydrogen Sulfide Production in Escherichia coli 总被引:7,自引:1,他引:6
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Porter Layne A. S. L. Hu Albert Balows Betty R. Davis 《Journal of bacteriology》1971,106(3):1029-1030
Two strains of Escherichia coli which produce hydrogen sulfide appear to have acquired this ability via transfer of genetic material from another genus. 相似文献