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151.
There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.   相似文献   
152.
153.
Mosquito densoviruses generally establish persistent infections in mosquito cell lines including the C6/36 Aedes albopictus cell line. In contrast, the closely related Haemagogus equinus densovirus (HeDNV) causes dramatic cytopathic effects in the C6/36 Aedes albopictus cell line. Infection of C6/36 cells by HeDNV causes internucleosomal fragmentation of host chromosomal DNA, changes in cellular morphology (membrane budding, apoptotic bodies), caspase activation and exposure of phosphatidylserine on the cellular membrane. This is accompanied by a higher rate of infection and more vigorous production of virus in these cells. These observations are consistent with the induction of apoptosis during infection. In contrast, expression of AeDNV proteins in C6/36 cells does not cause obvious cytopathic effects although NS1 expression causes accumulation of cells in G2 phase. C6/36 cells persistently infected with AeDNV were not protected from superinfection with HeDNV. Thus, there does not seem to be an antiviral state induced by AeDNV persistent infection.  相似文献   
154.
Maternal uniparental disomy for the entire chromosome 7 hasso far been reported in three patients with intrauterine andpostnatal growth retardation. Two were detected because theywere homozygous for a cystic fibrosis mutation for which onlythe mother was heterozygous, and one because he was homozygousfor a rare COL1A2 mutation. We investigated 35 patients witheither the Silver-Russell syndrome or primordial growth retardationand their parents with PCR markers to search for uniparentaldisomy 7. Four of 35 patients were found to have maternal disomy,including three with isodisomy and one with heterodisomy. Thedata confirm the hypothetical localization of a maternally imprintedgene (or more than one such gene) on chromosome 7. It is suggestedto search for UPD 7 in families with an offspring with sporadicSilver-Russell syndrome or primordial growth retardation.  相似文献   
155.
Research into Alzheimer’s disease (AD) has been guided by the view that deposits of fibrillar amyloid-β peptide (Aβ) are neurotoxic and are largely responsible for the neurodegeneration that accompanies the disease. This ‘amyloid hypothesis’ has claimed support from a wide range of molecular, genetic and animal studies. We critically review these observations and highlight inconsistencies between the predictions of the amyloid hypothesis and the published data. We show that the data provide equal support for a ‘bioflocculant hypothesis’, which posits that Aβ is normally produced to bind neurotoxic solutes (such as metal ions), while the precipitation of Aβ into plaques may be an efficient means of presenting these toxins to phagocytes. We conclude that if the deposition of Aβ represents a physiological response to injury then therapeutic treatments aimed at reducing the availability of Aβ may hasten the disease process and associated cognitive decline in AD.  相似文献   
156.
Neurocysticercosis, a parasitic infection of the human central nervous system caused by Taenia solium, is a leading cause of seizures. Seizures associated with neurocysticercosis are caused mainly by the host inflammatory responses to dying parasites in the brain parenchyma. We previously demonstrated sequential expression of Th1 cytokines in early-stage granulomas, followed by expression of Th2 cytokines in later-stage granulomas in murine cysticercosis. However, the mechanism leading to this shift in cytokine response in the granulomas is unknown. Neuropeptides modulate cytokine responses and granuloma formation in murine schistosomiasis. Substance P (SP) induces Th1 cytokine expression and granuloma formation, whereas somatostatin inhibits the granulomatous response. We hypothesized that neuropeptides might play a role in regulation of the granulomatous response in cysticercosis. To test this hypothesis, we compared expression of SP and expression of somatostatin in murine cysticercal granulomas by using in situ hybridization and immunohistochemistry. We also compared expression with granuloma stage. Expression of SP mRNA was more frequent in the early-stage granulomas than in the late-stage granulomas (34 of 35 early-stage granulomas versus 1 of 13 late-stage granulomas). By contrast, somatostatin was expressed primarily in later-stage granulomas (13 of 14 late-stage granulomas versus 2 of 35 early-stage granulomas). The median light microscope grade of SP mRNA expression in the early-stage granulomas was significantly higher than that in the late-stage granulomas (P = 0.008, as determined by the Wilcoxon signed rank test). By contrast, somatostatin mRNA expression was higher at later stages (P = 0.008, as determined by the Wilcoxon signed rank test). SP and somatostatin are therefore temporally expressed in granulomas associated with murine cysticercosis, which may be related to differential expression of Th1 and Th2 cytokines.  相似文献   
157.
We present a girl with mild manifestations of the Brachmann-de Lange syndrome (BDLS) with gradual change of the phenotype. Her findings support the hypothosis of variability of the phenotypic spectrum of the disorder.  相似文献   
158.
159.
The dopamine hypothesis of schizophrenia proposed that dopaminergic pathways are involved in the etiology of the disease. In particular, interest among psychiatrists has focused on the D2 receptor because of its affinity to antipsychotic drugs. Recently a new dopamine receptor gene has been cloned, and named the dopamine D3 receptor. The D3 receptor is a potential site for antipsychotic drug action and may be involved in the pathophysiology of schizophrenia. We have carried out a linkage study between the susceptibility gene for schizophrenia and polymorphism of the dopamine D3 receptor gene in two Japanese pedigrees. The LOD scores were negative for, all genetic models and for all affective status at a recombination fraction θ = 0. Linkage of DRD3 has been excluded for the model 1 (dominant model) and the model13 (recessive model). The LOD score was - 3.43 at θ = 0 for model 1 (dominant model) and broad definition of affected status. These results were consistent with previous studies. © 1994 Wiley-Liss, Inc.  相似文献   
160.
This study compared the ability of foetal thymic epithelium depleted of lymphocytes and dendritic cells, by low temperature or deoxyguanosine (dGuo) treatment in organ culture, to reconstitute T-cell function in nude mice. It is shown that renal capsule grafts of either type could promote the development of functional T lymphocytes in the periphery, as judged by in vivo assays. Both syngeneic and allogeneic thymic epithelium endowed nude mice with the capacity to mount IgG antibody and delayed-type hypersensitivity (DTH) responses to the T-dependent antigen ovalbumin (OVA). Functional reconstitution was accompanied by the appearance of Thy-1-bearing cells in the spleens of thymic grafted nude mice. The results from allogeneically grafted recipients show that a substantial population of peripheral T cells was present that collaborated with B cells and other antigen-presenting cells (APC) which do not express major histocompatibility complex (MHC) molecules of the thymus donor haplotype.  相似文献   
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