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The study aimed to clarify the role of apoptosis in pentachlorophenol (PCP) induced testicular, ovarian and renal cell genotoxicity of Heteropneustes fossilis. It was further intended to find the target germ cell type and assess the cellular and nuclear damage. Treatment of PCP was used for multiduration on the germinal tissues and they were processed to detect structural changes by light and electron microscopic evaluation and kidney cells for subsequent detection of DNA fragmentation by agarose gel electrophoresis. Findings suggest functional and morphological changes in the tissues are due to apoptosis, as evidenced by some biochemical and cytological signs. Histological observation on germinal epithelium reveals cell suicidal symptoms such as vacuolization, liquefied regions in the cytoplasm of oocytes, margination of nuclei, clumping of chromatin, and compaction of cytoplasmic organelle. Biochemical manifestation concurrent to this, is; cleavage of kidney cell DNA into low molecular weight fragments confirming apoptosis. Subsequently, it is further cleaved into nucleosome size fragments or its multiples. Ultra-structural histopathology and DNA studies conclusively lead to the PCP induced apoptosis in the exposed cell types. Results further support the usefulness of this assay in the related studies and its feasibility in generating a base line data.  相似文献   
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Diabetic patients usually avoid germinated endosperm of sugar palm (GESP) and elephant foot yam tuber (EFYT), fearing that these may further deteriorate existing hyperglycemia. In the present study, this suspicion was investigated by analyzing the nutrients and following the animal experiments by supplementary feeding powder of GESP, EFYT, and their mixture in addition to the regular diet for the six consecutive weeks. Next three weeks, the powder was withdrawn, and fasting blood glucose (FBG) levels were recorded from the beginning. The results clearly showed that these foodstuffs significantly (P < 0.001) reduced FBG levels of alloxan-induced diabetic rats. The mixture of GESP & EFYT showed the maximum antidiabetic effects followed by GESP and EFYT, respectively. GESP, as well as the mixture, returned the FBG levels of diabetic rats within the normal range by the end of the 6th week, even after withdrawing the powder, but not by the EFYT. These results suggested that the foodstuffs may restore the damaged pancreatic β-cell functions by the end of the 6th week. Nutrient contents like fiber, zinc, as well as antidiabetogenic phytochemicals present in these foodstuffs, could perform these functions.  相似文献   
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As part of a clinical study designed to modulate oestrogen and progestogen receptor (ER and PR) binding site concentrations prior to chemotherapy ER and PR levels have been estimated immediately before treatment, after ethynyloestradiol (EE, 10 micrograms/day, 1 week) and after medroxyprogesterone acetate (MPA, 500 mg/day i.m., 2 weeks) in tumour tissue from 14 women with advanced breast cancer. There was no consistent change after EE treatment. MPA tended to decrease ER and PR levels, though some increases were also seen. Responses (10 complete and 3 partial remissions) to sequential cyclical hormono-chemotherapy were not related to ER or PR levels prior to chemotherapy.  相似文献   
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Abstract— The lipid composition of chick brain and sciatic nerve was determined during development. It was confirmed that the addition of CaCl2 to solvents during the extraction of lipids from brain results in much higher yields of diphosphoinositides particularly from unmyelinated embryo brain. Unlike the earlier report for rat brain, the recovery of triphosphoinositides was also Substantially increased. The amount of CaCl2, required to achieve optimal recoveries decreased with increasing age and addition of more than this optimal amount depressed the yields of polyphosphoinositides, particularly triphosphoinositides. CaCl2, addition did not improve the yield of diphosphoinositides from sciatic nerve of any age but drastically reduced recovery of triphosphoinositidcs. Differenccs in the effect of CaCl2 were not the result of variation in the tissue concentrations of calcium or magnesium.
The lipid composition of sciatic nerve closely reflected that of the myelin. Both polyphosphoinositides were absent initially and their accumulation paralleled that of cerebrosides and sulfatides. The concentration of diphosphoinositides remained constant after the period of most active myelination while triphosphoinositides and the galactolipids continued to increase suggesting maturational changes in the myelin composition. The pattern of deposition in chick brain was similar except for the much greater contribution of non-myelin structures. Both polyphosphoinositides were present in equimolar amounts in pre-myelination embryonic tissue. The concentration of diphosphoinositides increased during active myelination only while triphosphoinositides continued to increase thereafter.  相似文献   
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