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181.
Trophinin, tastin, and bystin have been identified as molecules potentially involved in human embryo implantation. Both trophoblasts and endometrial epithelial cells express trophinin, which mediates apical cell adhesion through homophilic trophinin-trophinin binding. We hypothesized that trophinin's function in embryo implantation is unique to humans and investigated the expression of trophinin, tastin, and bystin in ectopic pregnancy, a condition unique to humans. In tubal pregnancies, high levels of all three were found in both trophoblasts and fallopian tubal epithelia. Trophinin expression in maternal cells was particularly high in the area adjacent to the trophoblasts, whereas trophinin was barely detectable in intact fallopian tubes from women with in utero pregnancies or without pregnancies. When explants of intact fallopian tube were incubated with the human chorionic gonadotrophin (hCG), trophinin expression was enhanced in epithelial cells. Since the trophectoderm of the human blastocyst secretes hCG before and after implantation, these results suggest that hCG from the human embryo induces trophinin expression by maternal cells. As both beta-subunit of hCG and trophinin genes have diverged in mammals, the present study suggests a unique role of hCG and trophinin in human embryo implantation, including the pathogenesis of ectopic pregnancy.  相似文献   
182.
Loss of heterozygosity (LOH) on the long arm of chromosome 7 was examined using 5 polymorphic marker probes on 98 gastric carcinomas to elucidate a novel locus for development and progression of the tumors. Twenty-six (32%) of 82 informative cases showed LOH on 7q on at least one locus of 5 loci. Among 5 loci, LOH at D7S95 locus was most frequent, the incidence being 53% in well-differentiated gastric carcinomas and 33% in poorly differentiated and scirrhous gastric carcinomas respectively. At 3 loci, c-met, D7S63 and D7S22, the incidence of LOH was about 30% and 10% in well-differentiated and poorly differentiated gastric carcinoma cases respectively. In contrast, LOH at D7S64 was not detected in any gastric-carcinoma cases. Deletion mapping of 7q revealed that D7S95 locus was the essential region of LOH. Eight (62%) of 13 cases with LOH at D7S95 locus belonged to the most advanced stage grouping. Furthermore, 6 (75%) of 8 cases with abdominal dissemination showed LOH at D7S95. Therefore, cases with LOH at D7S95 showed significantly worse prognosis than the cases without the LOH in the stage-III and stage-IV groups. These findings overall suggest that D7S95 locus on 7q may contain a candidate suppressor gene for the progression of gastric carcinoma.  相似文献   
183.
Frequent Amplification of the Cyclin E Gene in Human Gastric Carcinomas   总被引:8,自引:0,他引:8  
We searched for genetic alterations of the cyclin D1 and cyclin E genes in 45 human gastric carcinoma tissues. Expression of cyclin E mRNA and protein was also analyzed in eight of them by Northern and Western blots and immunohistochemical staining. The cyclin E gene was amplified 3–10 fold in seven gastric cancer tissues (15.6%), of which six were advanced gastric cancers. All of the cases with the cyclin E gene amplification displayed lymph node metastasis. Moreover, the case with the gene amplification overexpressed the cyclin E mRNA and protein. One of eight gastric cancer cell lines, MKN-7, shared the cyclin E gene amplification, and all of the gastric cancer cell lines expressed high levels of the cyclin E mRNA and protein even without gene amplification. Amplification of the cyclin D1 gene was not observed in any of the gastric carcinoma tissues or gastric carcinoma cell lines. These results suggest that the gene amplification and overexpression of cyclin E play an important role in the abnormal growth and progression of gastric carcinoma.  相似文献   
184.
Community Mental Health Journal - Research suggests that the COVID-19 pandemic has had a significant impact on those already living with mental health problems, though there is also evidence of...  相似文献   
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We aimed to develop a valid model of immunosuppression induced by intense exercise in rats. Rats were divided into three groups. In the rest (Rest) group, saliva was collected from resting rats on 4 consecutive days. In the exercise (Ex) group, rats ran on a treadmill until exhaustion (exercise time: 60.0 +/- 3.7 min), and their saliva was collected before and after exercise; the salivary glands were removed after exercise. In the control (Con) group, saliva collection and gland removal were also performed, but the rats did not exercise. Secretory immunoglobulin A (SIgA) concentrations in saliva and polymeric immunoglobulin receptor (pIgR) mRNA expression in the glands were measured. There was no significant change in SIgA concentration in the Rest group over 4 days. In the Ex group, SIgA concentration decreased significantly after exercise compared with before, whereas there was no significant change in the Con group. The expression of pIgR mRNA was significantly lower in the Ex group post-exercise than in the Con group. Our procedure for saliva collection appeared suitable, and the exercise-induced SIgA suppression was probably caused by a decline in pIgR mRNA expression. We propose to use this reproducible and reliable rat model of exercise-induced SIgA suppression in future studies.  相似文献   
187.
Object Identification of the risk of rupture and vulnerability of arterial plaque is not yet clearly understood. The aim of this study was to assess the clinical features of the motion of intraplaque contents (MIC) detected by B-mode ultrasonography. The MIC is characterized by the peculiar movement of the intraplaque contents that is not synchronized with the heartbeat; however, the movement of the carotid artery (CA) wall depends on the heartbeat. Methods From January 2008 to November 2010, 1798 consecutive patients with transient ischemic attacks (TIAs) or acute ischemic stroke underwent CA ultrasonography for the examination of the MIC. Patients with CA stenosis greater than 50% were followed up until they underwent carotid endarterectomy or CA angioplasty and stent placement. If neither of these procedures were used, the patients were followed up at 90 days. Chi-square and Mann-Whitney tests were performed to compare the categorical and continuous demographic data and risk factors. The effect of the MIC on the rate of recurrent cerebral ischemia was examined using Kaplan-Meier and univariate Cox regression analyses. Results One hundred and fifteen patients had CA stenosis greater than 50%. Among these 115 patients, 58 with a total of 59 CA stenoses had MIC. Twenty-four recurrent ischemic events were associated with MIC, whereas only 6 such events occurred in the absence of MIC. The MIC decreased event-free survival (log-rank test = 15.8, p < 0.001); univariate Cox analysis confirmed that MIC increased the risk of a recurrent ischemic event (HR 5.12, 95% CI 2.08-12.58; p < 0.001). Conclusions The MIC is one of the findings of vulnerable plaques. The MIC is more useful in predicting the recurrence of TIAs or ischemic events in patients with symptomatic CA stenosis.  相似文献   
188.
Inhibition of interleukin-1°aL (IL-1°aL) activity was detected in 7 of 41 serum samples from patients with rheumatoid arthritis (RA). These 7 sera inhibited not only IL-1°aL–induced endothelial cell adherence to neutrophils, but also IL-1°bT–induced endothelial cell adherence, although to a lesser extent. These sera showed no influence on tumor necrosis factor–induced endothelial cell adherence. No inhibitory activity was found in 40 sera from normal control subjects. Studies to further examine these effects included gel filtration analysis of 2 of the RA sera. The inhibitory activity was eluted near Mr 158 kd and above Mr 250 kd. Analysis by protein A affinity chromatography showed that IL-1–inhibitory activity was present in protein A–binding fractions. Purified IgG (by DE-52 column chromatography) from RA patients was found to be as potent an inhibitor as the protein A–binding fractions, which suggests that the major inhibitory activity in RA sera is attributable to IgG molecules. These purified IgG molecules also inhibited IL-1–induced proliferation of mouse thymocytes but did not influence IL-2–dependent proliferation of the CTLL-2 murine T cell line. The 7 patients whose sera showed IL-1–inhibitory activity had mild RA and low titers of rheumatoid factor. The findings, taken together, suggest a possible regulatory role of IL-1–inhibitory IgG in RA disease activity.  相似文献   
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