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1.
Streptococcus sanguis, usually considered a nonpathogen of the oral cavity, was isolated from blood cultures from a patient who was subsequently found to have a cecal adenocarcinoma. Further studies are needed to determine if Streptococcus sanguis infections have diagnostic implications similar to those of Streptococcus bovis. © 1995 Wiley-Liss, Inc.  相似文献   
2.
Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) are autoimmune sequelae of upper respiratory infections with group A streptococci (GAS). To gain a better understanding of the pathogenesis of these diseases, we examined the in vitro proliferative responses of peripheral blood mononuclear cells (PBMC) from RHD patients to human myocardial proteins in a T-cell Western assay. A number of myocardial proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were recognized by PBMC from both patients and controls. However, PBMC from a significant percentage of RHD patients (40%) responded to a discrete band of myocardial proteins migrating with an apparent molecular mass of 50 to 54 kDa while none of the control subject PBMC responded to this protein band (P < or = 0.0001). To further investigate the link between infections with GAS and autoimmune carditis, we studied the proliferative responses of PBMC from patients and controls to myocardial proteins before and after in vitro stimulation of the cells with opsonized GAS isolated from ARF patients. Priming of PBMC with rheumatogenic GAS caused the percentage of RHD patients responding to the 50- to 54-kDa myocardial proteins to increase from 43 to 90% (P < or = 0.0284). By contrast, PBMC from control subjects failed to recognize the 50- to 54-kDa myocardial proteins even after stimulation with the opsonized streptococci (P < or = 0.0001). The assay sensitivity was increased from 40 to 90% after priming of a patient's cells with opsonized GAS, but the positive predictive value was 100% in both unprimed and primed cultures. Antibodies generated to partially purified 50- to 54-kDa myocardial proteins did not cross-react with either streptococcal homogenates, purified M protein, myosin, laminin, or vimentin, suggesting a lack of cross-reactivity at the humoral level. This study suggests that the 50- to 54-kDa myocardial proteins contain a putative antigen that is preferentially recognized by T cells from RHD patients and demonstrates that exposure to streptococcal antigens enhances the ability of patients to recognize these proteins.  相似文献   
3.
To determine the prevalence of infection with Campylobacter fetus subsp. jejuni in Bangladesh, culture surveys were conducted among three populations. In Dacca, Campylobacter was isolated from 5.2% of 97 individuals with clinical dysentery and from 12.3% of 204 patients with only diarrhea. This difference may have resulted from a greater representation of young children in the second group. Campylobacter was isolated from 17.7% of the 141 healthy village children aged 1 to 5.5 years and from 38.8% of the 1-year-old children. More infected children (48%) had a history of recent diarrheal illness than did a group of matched controls (20%; P = 0.016). These findings suggest that campylobacter infection is common for Bangladeshi children. However, this organism may not cause diarrheal illness in all instances in which it is isolated.  相似文献   
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The anti-anginal effects of allopurinol were assessed in experimental model rats of angina and their effects were evaluated with amlodipine. In the vasopressin-induced angina model, oral administration of allopurinol in dose of 10 mg/kg revealed remarkably analogous effects in comparison with amlodipine such as dose-dependent suppression of vasopressin-triggered time, duration and severity of ST depression. In addition, allopurinol produced dose dependent suppression of plasma Malondialdehyde (MDA) level, systolic blood pressure, cardiac contractility and cardiac oxygen consumption; while in contrast, amlodipine minimally suppressed the elevation of plasma MDA level. Endothelial NO synthase (eNOS) expression, serum nitrate were strikingly increased, however lipid profile was significantly reduced. Seemingly, allopurinol was found to be more potent than amlodipine – a calcium channel antagonist. To conclude, it was explicitly observed and verified that on the ischemic electrocardiography (ECG) changes in angina pectoris model in rats, allopurinol exerts a significant protective effects, reminiscent of enhancement of vascular oxidative stress, function of endothelial cells, improved coronary blood flow in addition to the potential enhancement in myocardial stress. Moreover, our findings were in conformity with several human studies.  相似文献   
7.
The aim of this study was to evaluate the histopathological and apoptotic changes occurring in the rat ipsilateral and contralateral testes, after experimental spermatic cord torsion, and to explore and the role of poly(ADP‐ribose) polymerase (PARP) cleavage in testicular torsion–detorsion injury. A total of 37 Wistar albino rats were subjected to 720° unilateral spermatic cord torsion for 1, 2 and 4 h, followed by 4‐h reperfusion, or else to a sham operation (control group). Histology of the testicle was evaluated using haematoxylin–eosin (H&E) staining and Johnsen's scoring system. Germ cell apoptosis was evaluated via active caspase‐3 immunostaining, and PARP expression levels were evaluated via Western blotting. The mean Johnsen's tubular biopsy scores (JTBS) of the ipsilateral testicles were lower for all torsion groups than for the controls (P < 0.05), but the JTBS of the contralateral testicles were only lower in the 4‐h torsion group (P < 0.05). The mean apoptosis score (AS) of the ipsilateral and contralateral testicles was significantly higher in the torsion groups than in the sham group. AS increased correlatively with torsion time, in both testicles. The effect of testicular torsion on PARP cleavage was time dependent, with the highest effect observed after 4 h of testicular torsion (P < 0.05). Testicular torsion caused time‐dependent histological changes, apoptosis and increases in PARP cleavage. Our results suggest that testicular torsion–detorsion injury caused cell damage and germ cell apoptosis that apparently involved cleavage of PARP. Increased PARP cleavage could, in turn, lead to enhanced apoptosis.  相似文献   
8.

Objective

To assess the communication and interviewing skills of incoming residents and provide formative feedback to residents early in their training.

Design

New residents completed a 15-minute objective structured clinical examination (OSCE) assessing communication skills and a 12-question, self-administered content quiz at the start of their residency. Each resident was directly observed by a family physician in the OSCE and provided with 15 minutes of structured feedback, with an opportunity for questions and discussion. The entire process remained private and did not affect summative evaluations.

Setting

Family medicine residency training program at the University of Alberta in Edmonton.

Participants

First-year family medicine residents.

Main outcome measures

Residents’ scores on the OSCE and the content quiz; residents’ rating of the usefulness of the assessment and the likelihood it would lead to practice change.

Results

A total of 61 residents (93.8%) completed the skills assessment (50 Canadian graduates, 11 international graduates). The mean score for the content quiz was 20.6 out of a total possible score of 24. Resident scores ranged from 8 to 24. The mean score on the OSCE practice interview was 21.1 out of 30, with a range of 13 to 29. Learner feedback indicated that the skills assessment was useful (4.68 out of 6) and would lead to a change in practice (4.43 out of 6).

Conclusion

The introductory communication OSCE and quiz offer new residents an opportunity to gauge their baseline skill level, become aware of program expectations early in their training, and garner specific suggestions in a nonthreatening environment. This tailored approach helps orient residents while taking into account their previous experiences.  相似文献   
9.

Background

Prolonging atrial conduction time, as measured by tissue Doppler imaging (TDI), is an independent predictor of new onset or recurrent atrial fibrillation (AF). We investigated atrial conduction time and cardiac mechanical function in patients with impaired fasting glucose (IFG) using echocardiography.

Methods

Thirty patients with IFG (19 males and 11 females; age, 46.9?±?9.5?years) and 30 control subjects (18 males and 12 females; age, 46.7?±?8.2?years) were included. Atrial conduction time was determined from the lateral mitral annulus (PA lateral), septal mitral annulus (PA septal), and lateral tricuspid annulus (PA tricuspid) by TDI. Inter- and intra-atrial electromechanical delays (EMDs) were calculated. Left atrial (LA) volumes were determined according to the biplane area?Clength method. LA mechanical function parameters were calculated.

Results

LA passive emptying volume and LA passive emptying fraction decreased significantly in patients with IFG as compared with control subjects (p?<?0.001 and p?<?0.001, respectively). PA lateral and PA septal durations were significantly higher in patients with IFG than in the control group. However, no difference in PA tricuspid duration was observed between the two groups. Inter- and intra-atrial EMDs were significantly higher in patients with IFG as compared with the control subjects (median [interquartile range], 34.0 [17.0] vs. 17.0 [4.0], p?<?0.001 and 15.0 [8.5] vs. 7.5 [2.0], p?<?0.001, respectively). Positive correlations were detected between both inter- and intra-atrial EMD and glucose levels (r?=?0.76, p?<?0.001 and r?=?0.68, p?<?0.001, respectively). Additionally, a multiple linear regression analysis revealed that glucose levels were independently associated with inter-atrial EMD (???=?0.753, p?<?0.001).

Conclusion

We showed that IFG was associated with inter- and intra-atrial EMD. Our findings suggest that IFG is an etiological factor for the development of AF.  相似文献   
10.
Enteric pathogens associated with diarrhea were studied for two years at a diarrhea treatment center in rural Bangladesh. Enterotoxigenic Escherichia coli (ETEC) was the most frequently identified pathogen for patients of all ages. Rotavirus and ETEC were isolated from approximately 50% and approximately 25%, respectively, of patients less than two years of age. A bacterial or viral pathogen was identified for 70% of these young children and for 56% of all patients with diarrhea. Most ETEC isolates were obtained in the hot dry months of March and April and the hot wet months of August and September. Rotavirus identification peaked in the cool dry months of December and January, but infected patients were found year-round. The low case-fatality rates for patients with watery diarrhea and substantial dehydration further document the usefulness of treating patients with diarrhea with either a glucose- or sucrose-base electrolyte solution such as those used in this treatment center.  相似文献   
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