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Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases.  相似文献   
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Abstract

Monitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms.  相似文献   
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The response of tumours to adriamycin, and the cardiotoxicity of the drug, may be related to its pharmacokinetics and plasma levels. Rapid and sensitive methods of adriamycin determination in plasma and urine samples are thus needed. A comparative study shows that high-performance liquid chromatography with fluorimetric detection is a reliable and specific method, but it is relatively slow and sometimes lacks sensitivity. A commercially-available radioimmunoassay kit is convenient, but there is a cross reaction with the major metabolise adriamycinol and unless the assay is combined with an extraction step, it gives erroneously high results.  相似文献   
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Inflammatory pseudotumors have a diverse etiology, mycobacterial pseudotumor (MP) being one of them. MP is a rare entity; it has been reported infrequently in various organs and is extremely rare in the skin. We report a cutaneous MP in an immunosuppressed liver transplant recipient. The lesion consisted mostly of spindle cells, with small numbers of lymphocytes. Conventional acid-fast bacilli (AFB) stain revealed a large number of acid-fast bacilli within spindled histiocytes and the presence of Mycobacterium avium was determined by polymerase chain reaction. Given that the patient had a prior history of cutaneous squamous cell carcinoma resected and reconstructed in the same area, establishing the diagnosis was challenging. Immunohistochemical staining for lysosome-associated membrane protein was strongly positive, suggesting the presence of numerous mature lysosomes within infected spindle cells. Mycobacterial spindle cell pseudotumors can mimic malignant or benign neoplasms and should be considered in differential diagnosis of spindle cell lesions, especially in immunocompromised patients. Further studies are needed to determine mechanisms that permit the survival of mycobacteria within the lesions and that cause this unusual manifestation of infection.  相似文献   
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Many multiple sclerosis (MS) patients with normal pure tone threshold suffer from difficulties in their hearing especially speech perception in background noise, which is possibly because of incompetence of central auditory processing in this group. Three audiologic tests including gap in noise test (GIN), duration pattern sequence test (DPST) and word discrimination score (WDS) were used for comparing a number of aspects of central auditory processing between patients with MS and normal subjects. Approximate threshold and percent of correct answers in GIN test, percent of correct answers in DPST test and monosyllabic discrimination in WDS test were obtained through cross-sectional non-invasive study conducted on 26 subjects with relapsing-remitting multiple sclerosis who had mean age of 28.9 (SD 4.1) years, and 26 18–40-year-old ones with normal hearing and mean age of 27.7 (SD 5.2). Results of this study demonstrate increased approximate threshold and reduction of percent of correct answers obtained from GIN test in patients with multiple sclerosis (Pv = 0.0001). Furthermore in patients with MS, the average of correct answers in DPST was lower than normal subjects and finally performance of MS subjects in WDS test in quiet environment was correlated with GIN threshold (r = ?/624, Pr = /003). Results of the present study showed that patients with MS had defect in aspects of central auditory processing consisting of temporal resolution, auditory pattern and the memory for auditory task and difficulty in discrimination of speech in noisy environment that are related to the involvement of central nervous system.  相似文献   
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ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.  相似文献   
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A high frequency of mutations at the PTEN locus has been noticed in carcinoma of oral. However, the role of PTEN alternations and its association with outcome variables in the genesis of oral carcinoma is not understood fully. The purpose of our study was to examine the impact of PTEN and Bcl2 in the genesis of Squamous cell carcinoma of oral. Total numbers of 60 histopathologically confirmed cases of Squamous Cell Carcinoma and 15 cases of inflammatory lesion of oral specimens were studied. We assessed PTEN and bcl2 overexpression by the use of anti-PTEN and anti-bcl2 antibody through immunohistochemistry as directed by the manufacturer. There was progressive loss of PTEN expression from inflammatory lesion to OSCC (p<0.05). Significant differences were found for PTEN expression between inflammatory lesion and OSCC. The difference in expression pattern of PTEN in gender did not reach statistical significance (p>0.05). The expression of bcl2 was found to be restricted to tumor cells in well and moderately differentiated tumors. The intense expression of bcl2 was observed throughout the tumor cell in poorly differentiated tumors.The Overexpression of bcl2 and loss of PTEN expression were correlated to poor differentiation, lymph node involvement and late stages. Thus, alteration of PTEN and bcl2 is likely an important molecular event in pathogenesis and carcinogenesis of oral carcinoma.  相似文献   
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International Journal of Diabetes in Developing Countries - Diabetic retinopathy is an important problem worldwide. The purposes of this study were to measure and analyze VEGF and IGFBP3 level...  相似文献   
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