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61.
Apoptosis is a ubiquitous physiological mechanism of cell death regulating tissue mass and architecture. An attempt was made in the present study to see the occurrence of apoptotic cell death in three different treatment groups of rabbits viz. Control, HFD fed and HFD + Selenium fed. Apoptotic activity as checked by in situ DNA end labelling (TUNEL Assay) revealed excessive staining, mostly concentrated in plaque region both in fibrous as well as atheromatous plaque in HFD fed animals. However, in selenium (Se) supplemented animals, very little TUNEL staining could be seen, and even that confined to endothelial cells only. The control group on the other hand was totally devoid of any staining. Transmission Electron Microscopic (TEM) study also depicted the occurrence of apoptosis in aortic cells of HFD fed animals and very little in Se supplemented animals. Apoptotic activity has been discussed in relation to oxidative stress in HFD fed group. bcl-2, though an antiapoptotic oncoprotein, was found to be expressed more in atherogenic group as compared to control/HFD + Se treatment. On the whole, the study highlighted the occurrence of apoptotic process in atherosclerosis and the role of Se, a potent antioxidant, in inhibition of apoptotic process in HFD fed animals.  相似文献   
62.
The spindle checkpoint transiently prevents cell cycle progression of cells that have incurred errors or failed to complete steps during mitosis, including those involving kinetochore function. The molecular nature of the primary signal transmitted from defective kinetochores and how it is detected by the spindle checkpoint are unknown. We report biochemical evidence that Bub1, a component of the spindle checkpoint, associates with centromere (CEN) DNA via Skp1, a core kinetochore component in budding yeast. The Skp1's interaction with Bub1 is required for the mitotic delay induced by kinetochore tension defects, but not for the arrest induced by spindle depolymerization, kinetochore assembly defects, or Mps1 overexpression. We propose that the Skp1-Bub1 interaction is important for transmitting a signal to the spindle checkpoint pathway when insufficient tension is present at kinetochores.  相似文献   
63.
Macrocyclic complexes of Mn(II) were synthesized by template condensation using 2,6-diaminopyridine and diethylenetriamine with malonic, succinic, glutaric and adipic acids. The reaction proceeded smoothly to completion. These 16- to 24-membered N(6), but behaving as tetradentate, macrocyclic complexes were characterized by elemental analyses, molecular weight determinations, infrared, electronic, mass and X-ray spectral analyses. The elemental analyses are consistent with the formation of complexes [Mn(N(6)L(n))Cl(2)]. All the complexes are stable and monomeric in nature, as indicated by the molecular weight determinations. The spectral studies confirmed the proposed framework of the new macrocyclic complexes and indicated an octahedral geometry around the central metal atom. The complexes were screened in vitro against a number of pathogenic fungi and bacteria to assess their growth-inhibiting potential. The testicular sperm density, sperm morphology, sperm motility, density of cauda epididymis, spermatozoa and fertility in mating trials and the biochemical parameters of the reproductive organs of the rat were examined and are discussed.  相似文献   
64.

Background  

Sweat gland adenocarcinoma is a rare malignancy with high metastatic potential seen more commonly in later years of life. Scalp is the most common site of occurrence and it usually spreads to lymph nodes. Liver, lung and bones are the distant sites of metastasis with fatal results. The differentiation between apocrine and eccrine metastatic sweat gland carcinoma is often difficult. The criteria's are inadequate to be of any practical utility.  相似文献   
65.
Adrenomedullin expression in pathogen-challenged oral epithelial cells   总被引:4,自引:0,他引:4  
Adrenomedullin, a multifunctional peptide, is expressed by many surface epithelial cells and, previously, we have demonstrated that adrenomedullin has antimicrobial activity. The oral cavity contains an epithelium that is permanently colonized by microflora, yet infections in a host are rare. We exposed oral keratinocytes to whole, live cells from four microorganisms commonly isolated from the oral cavity, Porphyromonas gingivalis, Streptococcus mutans, Candida albicans and Eikenella corrodens. There was upregulation of protein and gene expression in these cells in response to bacterial suspensions, but not with the yeast, Candida albicans. We propose there is a potential role for microbial products in enhancing mucosal defense mechanisms and that adrenomedullin participates in the prevention of local infection, thus contributing to host defense mechanisms.  相似文献   
66.
Detection of Theileria annulata carrier cattle by PCR   总被引:2,自引:0,他引:2  
A simple method for treating bovine blood samples for direct detection of T. annulata in carriers, after polymerase chain reaction (PCR) amplification of small subunit ribosomal RNA (SSU rRNA) gene is described. The threshold of detection of the PCR-assay was an erythrocytic parasitaemia of 0.00008% corresponding to 16 infected bovine erythrocytes. In 50 known carriers, 42 were positive in PCR, in which 8 cattle revealed presence of T. annulata in stained blood smear under microscope.  相似文献   
67.
Genetic testing for mutations in BRCA1 and BRCA2, two genes predisposing to breast and ovarian cancers, is available to women with a relevant family history. The aim of this study was to estimate the positive and negative predictive value of clinical sequence analysis of these genes. A reference graph showing positive and negative predictive values over a range of pre-test risk was derived, taking into account the sensitivity and specificity of a full-sequence analysis test. High positive and negative predictive values were found for women with pre-test risk between 4% and 40%, a range of risk commonly seen in clinical testing. The predictive value of full sequence and single-site analysis of BRCA1 and BRCA2, therefore, compares favorably with other diagnostic medical tests. Our results provide a numerical estimate of the predictive value of BRCA testing, and as such, provide a valuable tool to healthcare providers and families as they interpret BRCA1 and BRCA2 test results.  相似文献   
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Seed germination studies onTrichodesma amplexicaule were carried out. Seeds show abnormal behaviour of germination which is termed "Chalazal germination". This abnormal behaviour of germination is due to the presence of an obturator at the micropylar end. Seeds showed maximum (60 per cent) germination with 110 min concentrated H2SO4 treatment.  相似文献   
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