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141.
Chromogranin A (CgA) is a neuroendocrine protein that undergoes proteolytic cleavage in secretory granules. The aim of the present study was to characterize the peptides WE14 and EL35 that are derived from evolutionarily conserved regions of CgA in rat and human endocrine tissues. In the rat pituitary, HPLC analysis revealed that WE14 is present as a single immunoreactive peak, whereas EL35 elutes in two molecular forms. Authentic WE14 is also produced in both rat and human adrenal glands, while EL35 displays a variable elution profile depending on the tissue extract, indicating the existence of different forms of EL35 in these tissues. Immunohistochemical labeling of the rat pituitary showed that WE14 and EL35 occur in gonadotropes and melanotropes, but not in corticotropes. A strong immunoreaction for both peptides was also observed in rat adrenochromaffin cells. In the human adrenal gland, the WE14 and EL35 antisera revealed intense labeling of adrenomedullary cells in adult and nests of chromaffin progenitor cells in fetal adrenal. Finally, WE14 and EL35 immunoreactivity was detected in pheochromocytoma tissue where WE14 occurred as a single immunoreactive form, while EL35 displayed different forms. The observations that WE14 and EL35: (1). have been preserved during vertebrate evolution, (2). are processed in a cell-specific manner, and (3). occur during ontogenesis of the adrenal gland strongly suggest that these peptides play a role in endocrine tissues. In addition, the existence of differentially processed CgA-derived peptides in normal and tumorous tissues may provide new tools for the diagnosis and prognosis of neuroendocrine tumors.  相似文献   
142.
Muscle temperature was measured by telemetry in giant Atlantic bluefin tuna whilst the tuna were free-swimming in large pounds. Muscle temperature tended to remain steady at about 24°C; water temperature ranged from 9 to 17°C. Muscle temperature was much less variable than stomach temperature in these fish. Muscle temperature varied less than 3°C whereas stomach temperature varied by as much as 14°C.  相似文献   
143.
Cellulase-free xylan-degrading enzyme preparations from Acrophialophora nainiana, Humicola grisea var. thermoidea and two Trichoderma harzianum strains were used as bleaching agents for Eucalyptus kraft pulp, prior to a chlorine dioxide and alkaline bleaching sequence. In comparison to the control sequence (performed without xylanase pretreatment), the sequence incorporating enzyme treatment was more effective. Removal of residual lignin was indicated by a reduction in kappa number. Overall, enzyme preparations from T. harzianum were marginally more effective in reducing pulp viscosity and chlorine chemical consumption and improving the brightness of the kraft pulp. However, the highest reduction in pulp viscosity was mediated by the xylanase preparation from A. nainiana. Xylanase pretreatment compares very favorably with that of chemical pulping. Journal of Industrial Microbiology & Biotechnology (2002) 28, 204–206 DOI: 10.1038/sj/jim/7000227 Received 27 April 2001/ Accepted in revised form 03 November 2001  相似文献   
144.
Patterns of human development are shifting from concentrated housing toward sprawled housing intermixed with natural land cover, and wildlife species increasingly persist in close proximity to housing, roads, and other anthropogenic features. These associations can alter population dynamics and evolutionary trajectories. Large carnivores increasingly occupy urban peripheries, yet the ecological consequences for populations established entirely within urban and exurban landscapes are largely unknown. We applied a spatial and landscape genetics approach, using noninvasively collected genetic data, to identify differences in black bear spatial genetic patterns across a rural‐to‐urban gradient and quantify how development affects spatial genetic processes. We quantified differences in black bear dispersal, spatial genetic structure, and migration between differing levels of development within a population primarily occupying areas with >6 houses/km2 in western Connecticut. Increased development disrupted spatial genetic structure, and we found an association between increased housing densities and longer dispersal. We also found evidence that roads limited gene flow among bears in more rural areas, yet had no effect among bears in more developed ones. These results suggest dispersal behavior is condition‐dependent and indicate the potential for landscapes intermixing development and natural land cover to facilitate shifts toward increased dispersal. These changes can affect patterns of range expansion and the phenotypic and genetic composition of surrounding populations. We found evidence that subpopulations occupying more developed landscapes may be sustained by male‐biased immigration, creating potentially detrimental demographic shifts.  相似文献   
145.
The response of sole and intercropped cereal to nitrogen fertilization was compared in three contrasting cropping systems, sorghum/pigeonpea, maize/groundnut, and sorghum/cowpea. The cereal in these systems responded to nitrogen similarly as in sole cropping, although different legumes affected the cereal differently. There was no current season benefit from the legume, whether it matured earlier or later than the cereal, and for high yields the cereal in intercropping needs fertilizer application. Response to nitrogen varied with the amount and distribution of seasonal rainfall. With increased nitrogen fertilizer applied to the intercropped cereal, the legume yields were suppressed. The optimum dose for the intercropped cereal was similar to that for sole cropping but it was 50% less in a dry year particularly, on a shallow Alfisol. The combined yields of both crops made intercropping more profitable than sole cropping. The relative advantage of intercropping was high in the sorghum/pigeonpea system (40 to 70%) because of the greater temporal difference between species, and moderate in the maize/groundnut (13 to 35%), and sorghum/cowpea (18 to 25%) systems. Although the relative advantage of intercropping (expressed as Land Equivalent Ratio (LER)) decreased with N, the economic value, of the advantage was little affected within the optimum N range because absolute yields increased with fertilization.  相似文献   
146.
Summary As part of a research program to determine the fate of N fertilizers applied to dryland sorghum in the semi-arid tropics,15N balance studies were conducted with various N sources in the greenhouse. Two American soils, Houston Black clay (Udic Pellustert) and Windthorst sandy loam (Udic Paleustalf), similar in properties to the Vertisol and Alfisol in the semi-arid tropics of India, were employed. Experiments were conducted with large pots containing 20 or 60 kg of soil which was subjected to several watering regimes. The15N not accounted for in the plant and soil was presumably lost. Losses of N on calcareous Houston Black clay were greatest for broadcast urea, 16%–28%. Amendment of broadcast urea with 2% phenyl phosphorodiamidate, a urease inhibitor, reduced N losses only slightly to 15%–20%. Point placement of urea at a 6 cm soil depth reduced losses to 1%–11%. Granule size had no effect on N loss from point-placed urea. Ammonia volatilization was apparently the main N loss mechanism, since N losses from sodium nitrate were less than 7%, except when the soil surface was waterlogged. N losses on the Windthorst soil averaged 30% from urea and 11% from ammonium nitrate. Amendment of urea with urea phosphate to form a 27% N and 13% P product reduced fertilizer N losses but did not increase grain yield on Windthorst soil. N losses were also less from ammonium nitrophosphate than from urea. Band and point placement of urea 6 cm below the soil surface were equally effective in reducing N loss on Houston Black clay. The findings give credence to the recommendation of deep band placement for urea in the semi-arid tropics.  相似文献   
147.
In Brazil, the epicenter of the Zika crisis, brown, black, and indigenous poor women living in municipalities with scarce resources were disproportionally affected. The gendered consequences of the epidemic exposed how intersectional lenses are central to understand the impact of public health emergencies in the lives of women and girls. The demand for Zika-affected children and women to be research participants is relevant for an ethical analysis of participant protection procedures during a crisis. We investigated how women experienced research participation by analyzing their narratives. Two-year-long longitudinal qualitative study in Brazilian sites located in the epidemic's epicenter was performed using mixed methods: ethnography with women from two distinct states and individual semi-structured interviews with five women in different Zika-affected states, four of which were community leaders. All women in the study were mothers or grandmothers of Zika-affected children. Thematic analysis was used for data evaluation. Women perceived being pressured to participate in research and a lack of benefit sharing. Structural determinants of gender inequality, such as its effect on power distribution, were found to impact research participant protection. Formal procedures for research protocols approvals were insufficient in protecting participants because these instruments were unable to account for structural aspects. Communitarian mobilization, through WhatsApp groups, was found to be an important mechanism to create conditions to challenge oppressive structures. Strengthening public health, effective community-based participation in research planning and implantation of ethical strategies that promotes gender equality can have transformative effect on unequal power structures and promote participant protection.  相似文献   
148.
Alternariosis is a fungal infection usually described in immunodeficient patients. We report a case of cutaneous alternariosis in a renal transplant recipient caused by Alternaria alternata. The patient was treated with intralesional amphothericin B and surgical excision of one non-responding lesion was performed.  相似文献   
149.
150.
Huntington's disease (HD) is caused by an expansion of CAG repeats in the HTT gene, leading to expression of mutant huntingtin (mHTT) and selective striatal neuronal loss, frequently associated with mitochondrial dysfunction and decreased support of brain-derived neurotrophic factor (BDNF). New neurons derived from the subventricular zone (SVZ) are apparently not able to rescue HD pathological features. Thus, we analyzed proliferation, migration and differentiation of adult SVZ-derived neural stem/progenitor cells (NSPC) from mild (6 month-old (mo)) and late (10 mo) symptomatic HD YAC128 mice expressing full-length (FL)-mHTT versus age-matched wild-type (WT) mice. SVZ cells derived from 6 mo YAC128 mice exhibited higher migratory capacity and a higher number of MAP2 + and synaptophysin + cells, compared to WT cells; MAP2 labeling was enhanced after exposure to BDNF. However, BDNF-evoked neuronal differentiation was not observed in 10 mo YAC128 SVZ-derived cells. Interestingly, 6 mo YAC128 SVZ-derived cells showed increased intracellular Ca2+ levels in response to KCl, which was potentiated by BDNF, evidencing the presence of differentiated neurons. In contrast, KCl depolarization-induced intracellular Ca2+ increase in 10 mo YAC128 SVZ-derived cells was shown to be increased only in BDNF-treated YAC128 SVZ-derived cells, suggestive of decreased differentiation capacity. In addition, BDNF-untreated NSPC from 10 mo YAC128 mice exhibited lower mitochondrial membrane potential and increased mitochondrial Ca2+ accumulation, in relation with NSPC from 6 mo YAC128 mice. Data evidence age-dependent reduced migration and decreased acquisition of a neuronal phenotype, accompanied by decreased mitochondrial membrane potential in SVZ-derived cells from YAC128 mice through HD symptomatic phases.  相似文献   
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