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91.
Apoptosis in the ovary: molecular mechanisms 总被引:19,自引:0,他引:19
Hussein MR 《Human reproduction update》2005,11(2):162-177
Cell death was first described in rabbit ovaries (Graaffian follicles), the phenomenon being called 'chromatolysis' rather than apoptosis. In humans, the ovarian endowment of primordial follicles is established during fetal life. Apoptotic cell death depletes this endowment by at least two-thirds before birth, executed with the help of several players and pathways conserved from worms to humans. To date, apoptosis has been reported to be involved in oogenesis, folliculogenesis, oocyte loss/selection and atresia. Several pro-survival and pro-apoptotic molecules are involved in ovarian apoptosis with the delicate balance between them being the determinant for the final destiny of the follicular cells. This review critically analyses the current knowledge about the biological roles of these molecules and their relevance to the dynamics of follicle development. It also presents the existing literature and assesses the gaps in our knowledge. 相似文献
92.
Zusammenfassung Es wird über einen Fall akuter Erythroleukämie mit G-Trisomie berichtet und die mögliche Bedeutung hereditärer Faktoren für die Manifestation akuter Leukämien diskutiert.
Summary The cytogenetic analyses of direct bone marrow preparations in a 53 years old male with acute erythroleukaemia of 9 months disease history, revealed persistently a G-trisomy in a dominant cell line with 47 chromosomes. The peripheral blood culture preparations with phytohaemagglutinin exhibited normal diploid cell line.The frequent occurrence of akute leukaemia in Down's syndrome tempts to implicate that leukaemia with G-Trisomy having no signs of Down's syndrome is a somatic mutation initiated by some unknown hereditary recessive genes mechanisms.相似文献
93.
94.
K A Hussein D S Sanders P E Preece S M Hunter S M Nicoll 《Diagnostic cytopathology》1989,5(2):217-220
Aspirate from an argyrophil carcinoma ("carcinoid") of the breast showed malignant dispersed epithelial cells. With Diff-Quik, the cytoplasm was seen to be abundant, with prominent eosinophilic granularity. The nuclei were fairly uniform, round or oval, and eccentric and had a finely stippled chromatin pattern. On histology, the tumor appeared typical for argyrophil carcinoma, and staining with Grimelius for argyrophilic granules was positive. Membrane-bound neurosecretory granules were seen on electron microscopy. 相似文献
95.
Many human autoimmune diseases, including those of the thyroid gland, are affected by immune changes during pregnancy and the postpartum period. To investigate this influence, we have developed an animal model of pregnancy thyroiditis by using thyroglobulin (Tg)-induced experimental autoimmune thyroiditis (EAT). We now report a study of the post-partum period in mice with EAT. At 5 weeks postpartum, which was 9 weeks after the completion of a Tg immunization regime, the mean thyroiditis grade was significantly increased in the postpartum group from 0.23 to 0.43 (p<0.05) and the thyroiditis Index, which reflected both the frequency and severity of thyroiditis, was similarly increased compared to controls (29.0 vs 9.0). When Tg immunized CBA/J (H-2k) female mice were mated with BALB/c (H-2d) males, there was a similar increase in the severity of thyroiditis in the postpartum period as seen with CBA/J males suggesting that allogeneic factors were not able to further this postpartum exacerbation. Spleen cell IL-4 secretion was enhanced in the postpartum but only in the presence of thyroiditis indicating enhanced activity of Th2 immune responses. There were no differences in IFN-gamma secretion, titers of anti-Tg, CD8+ & CD4+ T cells and T cell chemokine receptor (CCR5, CCR3) expression between non-pregnant control mice with thyroiditis and postpartum thyroiditis. In summary, we found that the severity of EAT during the postpartum was significantly greater than in non-pregnant control mice and was associated with enhanced Th2 immune responses. The allogenicity of the pregnancy had no influence on these findings. The lack of allogenic impact was in contrast to earlier observations in pregnancy itself where an exacerbation of thyroiditis was male strain-dependent and involved primarily Th1 responses. This indicated that the postpartum exacerbation of autoimmune thyroid disease was not a simple response to fetal antigens but secondary to unique postpartum factors. 相似文献
96.
Jones DC Gelder CM Ahmad T Campbell IA Barnardo MC Welsh KI Marshall SE Bunce M 《Tissue antigens》2001,58(1):19-23
Mycobacterium malmoense is an opportunistic mycobacterium that occasionally causes disease in non-immunosuppressed individuals. As only a few individuals exposed to these organisms actually develop clinical disease, it is possible there is a genetic component to susceptibility. CD1 molecules are capable of presenting antigens from more virulent mycobacteria to T cells; therefore, we were interested in discovering whether recently described polymorphisms in CD1 molecules modulated susceptibility to M. malmoense pulmonary disease. The CD1 system comprises five genes (CD1A, -B, -C, -D, and -E) located on chromosome 1 (1q22-23). CD1 molecules are structurally and functionally related to major histocompatibility complex (MHC) class I molecules and are expressed on dedicated antigen-presenting cells. The primary function of CD1 molecules is to present lipid and glycolipid antigens to T cells. We have developed an allele-specific polymerase chain reaction-sequence-specific primer (PCR-SSP) method of CD1 genotyping. Using this method, we compared the allele and haplotype frequencies of CD1 in 49 HIV-negative patients with M. malmoense pulmonary disease with those in 342 normal controls. The CD1A and CD1E alleles were nominally identified as CD1A*01, CD1A*02, CD1E*01 and CD1E*02, and the control gene frequencies were found to be 5%, 95%, 67% and 33%, respectively. No significant difference was observed between the patient and control cohorts. Positive linkage disequilibrium values of 0.73 were observed between CD1A*02 and CD1E*01 (P<0.0001; chi2 test), and 0.94 between CD1A*01 and CD1E*02 (P<0.0001; chi2 test). Typing was also performed for two previously described CD1D alleles (CD1D*01 and CD1D*02), although only CD1D*01 was detected. 相似文献
97.
G N Gephardt L F Shah R R Tubbs M Ahmad 《Archives of pathology & laboratory medicine》1990,114(9):961-965
Four cases of Wegener's granulomatosis involving lung are reported in which immunomicroscopy demonstrated that the parenchymal and vascular infiltrates were composed primarily of T cells and monocytes. No IgG, IgA, IgM, or C3 was identified in pulmonary vessels or alveolar septa. Ultrastructural studies failed to demonstrate dense deposits in alveolar septal capillaries or interstitium. These findings indicate that a cellular immune mechanism is active in these forms of pulmonary vasculitis and that immune complex deposition does not play a role. 相似文献
98.
Cerebral Processing of Acute Skin and Muscle Pain in Humans 总被引:12,自引:0,他引:12
99.
Inflammation: the link between insulin resistance, obesity and diabetes 总被引:41,自引:0,他引:41
Recent data have revealed that the plasma concentration of inflammatory mediators, such as tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), is increased in the insulin resistant states of obesity and type 2 diabetes, raising questions about the mechanisms underlying inflammation in these two conditions. It is also intriguing that an increase in inflammatory mediators or indices predicts the future development of obesity and diabetes. Two mechanisms might be involved in the pathogenesis of inflammation. Firstly, glucose and macronutrient intake causes oxidative stress and inflammatory changes. Chronic overnutrition (obesity) might thus be a proinflammatory state with oxidative stress. Secondly, the increased concentrations of TNF-alpha and IL-6, associated with obesity and type 2 diabetes, might interfere with insulin action by suppressing insulin signal transduction. This might interfere with the anti-inflammatory effect of insulin, which in turn might promote inflammation. 相似文献
100.
Mahmud Ahmad Hasan Abbas Sayedul Haque 《American journal of medical genetics. Part A》1993,46(4):369-371
A Pakistani kindred comprising 5 generations contained 9 males and 4 females with alopecia universalis as a single abnormality without any associated defects. The skin biopsy from the scalp showed hair follicles without hair. Analysis of the pedigree is strongly suggestive of autosomal recessive inheritance, and consanguineous loops could account for all affected persons being homozygous for the abnormal allele. © 1993 Wiley-Liss, Inc. 相似文献