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Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation.  相似文献   
3.

This study aimed to determine the seroprevalence and determinants of hepatitis B virus (HBV) infection among university students in Bangladesh. This cross-sectional study was conducted among 614 students from five universities in central Bangladesh. Data were collected on demographic information, immunization history, medical and blood transfusion history through the face-to-face interview. Blood samples were collected and screened for anti-HBsAg using ELISA, HBsAg Rapid Test-cassette, and immune chromatographic test. The overall seroprevalence of HBV infection was 5.0%, and vaccination coverage was 19.2% among the participants. Students having a history of surgery (OR 11.004, 95% CI 3.211–37.707), blood transfusion (OR 5.651, 95% CI 0.965–33.068), being married (OR 4.776, 95% CI 1.508–15.127), and not being vaccinated (OR 9.825, 95% CI 1.130–85.367) were at higher risk of being infected by HBV. This study showed the endemicity of HBV infection among the Bangladeshi population. Marriage, surgical or blood transfusion history, not being vaccinated were the determinants of HBV infection within the study population. Public health initiatives for preventing HBV infection at the university levels should be envisaged.

  相似文献   
4.
In order to better understand the role of intestinal CD1d, we sought to define the cellular localization and further characterize the biochemical structure of CD1d in human intestinal epithelial cells (IEC). Using a CD1d-specific rabbit anti-gst-CD1d antibody, immunoprecipitation of radiolabeled cell surface proteins detected a previously identified 37 kDa protein as well as a 48-50 kDa protein which were confirmed by Western blotting with a CD1d-specific mAb, D5. Immunoprecipitation of protein lysates with the CD1d-specific mAb, D5 and 51.1.3, and the beta2-microglobulin (beta2m)-specific mAb, BBM.1, followed by N-glycanase digestion and Western blotting with the D5 mAb showed that the 48-50 kDa protein was a beta2m-associated, CD1d glycoprotein. CD1d was immunolocalized to the apical and lateral regions of native small and large intestinal IEC as defined by confocal laser microscopy using the D5 mAb and the rabbit anti-gst-CD1d antibody. In addition, a large apical intracellular pool of CD1d was identified. Identical observations were made with polarized T84 cells. Selective biotin labeling of apical and basolateral cell surfaces followed by immunoprecipitation with the D5 mAb, N-glycanase digestion and avidin blotting confirmed the presence of glycosylated CD1d on both cell surfaces and immunolocalization of the 37 kDa non-glycosylated form of CD1d to the apical cell surface. These studies show that CD1d is located in an ideal position for luminal antigen sampling and presentation to subjacent intraepithelial lymphocytes.  相似文献   
5.

Background

Low birth weight (LBW) is considered as a major multifaceted public health concern. Seventy-two percent of LBW infants are born in Asia. An estimation of 8% LBW infants has been reported for Eastern Mediterranean region including Iran. This study investigated contributory factors of LBW in singleton term births in Tehran, Iran. Tehran is a multicultural metropolitan area and a sample from the general population in Tehran could be regarded as a representative sample of urban population in Iran.

Methods

This was a retrospective study using data from 15 university maternity hospitals in Tehran, Iran. Data on all singleton term births in these hospitals were extracted from case records during a one calendar year. Study variables included: maternal age, maternal educational level, history of LBW deliveries, history of preterm labor, cigarette smoking during pregnancy, number of parities, chronic diseases and residential area (Tehran versus suburbs of Tehran). In order to examine the relationship between LBW and demographic and reproductive variables the adjusted logistic regression analysis was performed.

Results

In all, data for 3734 term pregnancies were extracted. The mean age of women was 25.7 (SD = 5.3) years and 5.2% of term births were LBW. In addition to association between LBW and maternal age, significant risk factors for LBW were: history of LBW deliveries [adjusted odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.06–6.03], smoking during pregnancy (OR = 4.64, 95% CI = 1.97–10.95) and chronic diseases (OR for hypertension = 3.70, 95% CI = 2.25–6.06, OR for others = 2.04, 95% CI = 1.09–3.83).

Conclusion

The findings indicate that in addition to maternal age, history of LBW deliveries; smoking during pregnancy and chronic diseases are significant determinants of LBW in this population. This is consistent with national and international findings indicating that maternal variables and risk behaviors during pregnancy play important roles on LBW.  相似文献   
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OBJECTIVES: To investigate the correlation between in vitro susceptibility of isolates and clinical outcomes with telithromycin in respiratory tract infections. METHODS: The activity of telithromycin was determined by in vitro susceptibility testing of key respiratory tract pathogens isolated from patients with community-acquired pneumonia, acute exacerbations of chronic bronchitis or acute maxillary sinusitis enrolled in 14 Phase III/IV clinical trials evaluating the clinical efficacy of telithromycin. RESULTS: In this pooled analysis, telithromycin mode minimum inhibitory concentration (MIC) and MIC90, respectively, were: 0.016 and 0.03 mg/l against Streptococcus pneumoniae (n=626); 0.03 and 0.5 mg/l for penicillin-resistant S. pneumoniae (n=56); 0.03 and 1 mg/l for erythromycin-resistant S. pneumoniae (n=81); 2 and 4 mg/l against Haemophilus influenzae (including beta-lactamase producers; n=627); both 0.12 mg/l for Moraxella catarrhalis (n=159) and both 0.25 mg/l for Staphylococcus aureus (n=124). Telithromycin (5 or 7-10 days) resulted in overall clinical and bacteriologic success rates of 88.1% (1593/1808) and 89% (1593/1789), respectively. CONCLUSIONS: High levels of in vitro susceptibility to telithromycin are paralleled by high rates of clinical cure and bacteriologic eradication.  相似文献   
8.
The level of circulating endotoxin was determined in the sera from children hospitalized for treatment of diarrhea at the International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh. A significant level of endotoxin was detected in the sera from 23 (54%) of 42 children. On the other hand, in 32 normal controls, endotoxin was below the limits of detection of the assay. Antibiotic and fluid therapy markedly reduced the level of serum endotoxin and improved the general condition of most patients. Non-survivors (n = 5) had higher levels of circulating endotoxin before treatment than survivors (n = 37), suggesting a significant correlation between the serum endotoxin level before treatment and mortality. Malnutrition did not affect the serum endotoxin level in the patients with diarrhea. It was suggested that infection of Gram-negative bacteria might be involved in a significant number of patients with diarrhea in Bangladesh and that endotoxin might play a pathogenic role in those patients.  相似文献   
9.
This review systematically synthesized existing literature on group protocols of eye movement desensitization and reprocessing (EMDR) therapy for treating a range of mental health difficulties in adults and children. We conducted database searches on PsychINFO, EMBASE, MEDLINE, Web of Science, The Cochrane Library and Francine Shapiro Library up to May 2020, using PRISMA guidelines. Studies were included if they used at least one standardized outcome measure, if they present a quantitative data on the effect of group EMDR protocols on mental health difficulties and if they were published in English. Twenty-two studies with 1739 participants were included. Thirteen studies examined EMDR Integrative Group Treatment Protocol (IGTP), four studies examined EMDR Group Traumatic Episode Protocol (G-TEP), four studies EMDR Integrative Group Treatment Protocol for Ongoing Traumatic Stress and one study considered EMDR Group Protocol with Children. Of the 22 studies included, 12 were one-arm trials and 10 were two-arm trials. We assessed risk of bias using a revised Tool to Assess Risk of Bias in Randomized Trials (ROB 2) and Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I). Overall, the results suggested that Group EMDR protocols might be an effective tool in improving a wide range of mental health-related outcomes including posttraumatic stress disorder (PTSD), depression and anxiety. However, the included studies are limited to methodological challenges. The limitations and future directions are discussed.  相似文献   
10.
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