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91.
Cattle are an important reservoir of Escherichia coli O157:H7 leading to contamination of food and water, and subsequent human disease. This pathogen colonizes its hosts by producing several proteins such as Tir and EspA that are secreted by a type III secretion system. These proteins play a role in colonization of the intestine, suggesting that they might be useful targets for the development of a vaccine to reduce levels of this organism in cattle. Vaccination of cattle with proteins secreted by E. coli O157:H7 significantly reduced the numbers of bacteria shed in feces, the numbers of animals that shed, and the duration of shedding in an experimental challenge model. Vaccination of cattle also significantly (P=0.04) reduced the prevalence of E. coli O157:H7 in a clinical trial conducted in a typical feedlot setting. This strategy suggests it is possible to vaccinate cattle to decrease the level of E. coli O157:H7 shedding for the purpose of reducing the risk of human disease.  相似文献   
92.
Introduction: End-stage renal disease (ESRD) patients treated by haemodialysis (HD) have impaired endothelium-dependent vasodilatation and increased intima-media thickness (IMT) of the carotid artery The aim of the study was to analyse the relationships between parameters of chronic HD treatment and non-invasive assessments of preclinical atherosclerosis (endothelial dysfunction and carotid IMT) in ESRD patients on HD. Methods: Fifty-two (19 females, 33 males) adult patients on chronic maintenance (4.65 ± 3.29 years) HD aged 59.88 ± 15.49 years were investigated. Ultrasonographic studies were performed with a 7.5 MHz high-resolution probe. The common carotid artery IMT was measured. Brachial artery diameter was analysed to the rest. In order to assess flow-mediated dilatation (FMD), hyperaemia was induced by a pneumatic cuff, and an analysis of the diameter was performed 1, 2, 3 and 4 min after cuff deflation. Results: Significant differences were found in the average carotid IMT value between subjects with delivered dialysis dose (Kt/V) ≥1.2 and <1.2 (0.89 ± 0.21 vs 1.04 ± 0.11, P = 0.0045). A correlation between Kt/V and IMT (r = 0.366, P = 0.004) was demonstrated. FMD values of the brachial artery did not correlate with Kt/V. A correlation between low molecular weight heparin per kg of body mass and maximal percent of FMD was demonstrated (r = −0.242, P = 0.049). The maximal percent of brachial FMD was correlated with absolute difference between pre- and postdialysis pulse pressure values (r = −0.265, P = 0.033). In a partial correlation with haemoglobin as control, a variable significant correlation between total erythropoietin dose and maximal carotid IMT (r = −0.262, P = 0.036) was found. In a multiple linear regression model, Kt/V was independently correlated with carotid IMT values (β = −0.227, P = 0.0335). Conclusion: This study has demonstrated the association between HD procedure and early atherosclerosis markers. HD treatment has to be considered as potential modifying factor in atherosclerosis development.  相似文献   
93.
There are conflicting results of published studies about prognostic value of various factors in purulent renal infections. The purpose of this study was to identify and quantify potential risk factors for early and late treatment failure in such infections. A retrospective review of 75 renal suppurative infections, at three tertiary Serbian Clinics of Urology, was conducted. We considered numerous potential risk factors in a multivariate analysis. This series was comprised of 49 women and 26 men, with mean age of 56.7 years. There were 38 and 37 patients who experienced successful and unfavorable early treatment outcome, respectively. Overall mortality rate was 9.3%. Comorbidity [odds ratio (OR) = 1.6], complex suppurative pathological findings (OR = 3.6), presence of Pseudomonas spp. (OR = 6.7), multiple bacterial strains (OR = 2.7), and positive culture itself (OR = 3.6) were the predictors of poor early prognosis. A urological intervention and presence of pyonephrosis significantly increased the chance for good initial outcome (OR = 0.32 and 0.37, respectively). In the late treatment failure analysis presence of comorbidities (OR = 5.8) and treatment complications (OR = 7.5) significantly increased chance for fatal outcome. Patients’ baseline health status and complexity of suppuration itself were the most important predictors of clinical outcomes. Surgical drainage dominated over antimicrobial therapy.  相似文献   
94.
95.
Objective: To analyse the incidence, clinical presentation, and outcome of heart insufficiency in patients with chronic arteriovenous fistulas (AVF). Methodology: From 1991 to 2000 we treated 49 patients with traumatic AVF. The present study included 19 patients with AVF present for 6 months or longer, as it was presumed that these AVF will have an impact on cardiac overload. There were 16 male and three female patients with a mean age of 36 years (17–59). The time from injury to admission varied from 6 months to 33 years. Cardiological examination checked for dyspnoea and palpitation. ECG, chest X‐ray and ECHO‐cardiography were also performed. All AVF were deleted, magistral vessels reconstructed, non‐magistral obliterated, either surgically or by percutaneous embolization. Results: Mean follow up was 44.2 months (3–93). Serious heart insufficiency was seen in two patients only, with AVF in the subclavial vessels. Both suffered from serious heart disease prior to the therapeutic procedures that resulted in iatrogenic AVF, so it was difficult to connect heart insufficiency to the AVF alone. Despite surgical closure of AVF and intensive medical treatment, signs of heart insufficiency remained in both patients. Signs of cardiac overload were seen in six patients with long‐standing AVF in major vessels. Except for one patient who refused surgical closure of femoral AVF, the remaining five were symptom free for cardiac overload during the follow‐up period. Conclusion: In our series, heart insufficiency was an infrequent complication in long‐standing AVF, even when major vessels were involved.  相似文献   
96.
The main biologically active components of plants belonging to the genus Allium, responsible for their biological activities, including anti-inflammatory, antioxidant and immunomodulatory, are organosulfur compounds. The aim of this study was to synthetize the mixture of dipropyl polysulfides (DPPS) and to test their biological activity in acute hepatitis. C57BL/6 mice were administered orally with DPPS 6 h before intravenous injection of Concanavalin A (ConA). Liver inflammation, necrosis and hepatocytes apoptosis were determined by histological analyses. Cytokines in liver tissue were determined by ELISA, expression of adhesive molecules and enzymes by RT PCR, while liver mononuclear cells were analyzed by flow cytometry. DPPS pretreatment significantly attenuated liver inflammation and injury, as evidenced by biochemical and histopathological observations. In DPPS-pretreated mice, messenger RNA levels of adhesion molecules and NADPH oxidase complex were significantly reduced, while the expression of SOD enzymes was enhanced. DPPS pretreatment decreased protein level of inflammatory cytokines and increased percentage of T regulatory cells in the livers of ConA mice. DPPS showed hepatoprotective effects in ConA-induced hepatitis, characterized by attenuation of inflammation and affection of Th17/Treg balance in favor of T regulatory cells and implicating potential therapeutic usage of DPPS mixture in inflammatory liver diseases.  相似文献   
97.
AIM: To present the technique and efficacy of extended ankle and foot fasciotomy, as a surgical limb-salvage procedure associated with the successful revascularization after the gold interval. METHOD: A retrospective review of six patients at the age of 16- 79 years (mean 39) in the period from 1996 to 2003, treated with the extended ankle and foot fasciotomy. There were four males undergoing the delayed treatment of war injuries to the lower extremity, and two females with atherosclerotic occlusive disease (a. illiacae dex and a. poplitealis dex.). The average ishemic time in the wounded patients was 22 hours (range, 14-30 hours), and ischemic time in occlusive disease (range, 48-72 hours). Clinical signs, indications, surgical access and the technique of extended ankle and foot fasciotomy was reported. RESULTS: The obtained results were classified as early and late.There was no cases with lethal outcome. Incisional wounds closed 15 days after the intervention, using secondary suture or skin transplant sec. Thiersch. The satisfactory functional results were achieved in 4 of the patients, 1 had a small edema, while amputation was performed in 1 patient. CONCLUSION: In cases of prolonged foot ischemia with edema and paresthesia in the toes, extended ankle and foot fasciotomy should be performed as a surgical limb-salvage procedure.  相似文献   
98.
BACKGROUND/AIM: Modern treatment of cystic echinococcosis, except for surgical treatment and percutaneous drainage of cyst considers also administration of albendazole as a type of individual therapy. However, clinicians fear of the serious adverse effects of high doses of albendazole, first of all the elevation of serum transaminases activity, very frequently results in subdosing of albendazole and wrong conclusions its efficacy and safety. The aim of this study was to investigate adverse effects of a longterm, continual administration of high doses of albendazole in the treatment of patients with echinococcal disease. METHODS: A total of 42 patients (mean age 40.4 +/- 18.3 years) with echinococcal disease were included in the study. They were treated with continual administration of high doses of albendazole within the period of 4 to 6 months. The subgroups of 27 and 15 patients were treated with 15-20 mg/kg/day and with 21-25 mg/kg/day albendazole, respectively. The patients in the control group (18 with surgical treatment, 6 with percutaneous drainage of cyst) were treated with 800 mg albendazole per day (< 15 mg/kg body weight) in the cycles of 28 days (1-3 cycles) and a two-week pause between them. RESULTS: In the study group adverse effects of albendazole were registered in 20 (47.6%), whereas in the control group in 6 (30.0%) of the patients. In both subgroups elevated activity of serum transaminases were found more frequently in the study group compared to the control one (35.7% vs 25%, p < 0.05), especially in the patients who were treated with higher doses of albendazole. The patients in the study group, compared to the patients in the control group had significantly higher mean activity of serum alanin aminotransferase in the course of the second and third month of the therapy (p < 0.05). Administration of albendazole due to adverse effects was stopped in 3 (7.1%) of the patients in the study group. Two (4.8%) of them had a very high activity of serum transaminases and one had a muscle pains and high activity of serum creatine kinase. After the interruption of the therapy we documented a nonnalization of serum enzyme levels in all the patients. CONCLUSION: Longterm, continual administration of high doses of albendazole in the patients with echinococcal disease results in significant elevation of serum transaminases activity, compared to the patients treated with albendazole in the cycles, but in the majority of the patients serum transaminases activity was normalizated by the end of a 6-month period.  相似文献   
99.
OBJECTIVE: The autonomous proliferative response of endothelial cells to hypoxia has been shown to be dependent on activation of NAD(P)H oxidase, on the cytosolic Ca2+ load, and, consequently, on nuclear translocation of extracellular signal-regulated kinase (ERK)1/2 during transient hypoxia. The aim of the present study was to investigate whether poly(ADP-ribose) polymerase (PARP) is a downstream signal of NAD(P)H oxidase, mediating cytosolic Ca2+ load and hence nuclear translocation of ERK1/2 and endothelial cell proliferation. METHODS: Porcine aortic endothelial cells were incubated under hypoxic conditions for 40 min. Cytosolic [Ca2+] and reactive oxygen species (ROS) formation were measured in fura-2- and DCF-loaded cells, respectively. PARP activation was detected by immunocytochemistry, and endothelial cell proliferation was determined 24 h after 60 min of transient hypoxia. RESULTS: Inhibition of NAD(P)H oxidase with antisense oligonucleotide against the p22(phox) subunit, MEK/ERK signalling with UO 126 (30 microM), or PARP with PJ 34 (10 microM) leads to a marked reduction in hypoxia-induced cytosolic Ca2+ load and activation of PARP. Hypoxia-induced translocation of ERK1/2 and endothelial cell proliferation were also prevented when NAD(P)H oxidase or PARP were inhibited; however, hypoxic ROS formation was not affected in the presence of PARP inhibitor. CONCLUSION: PARP represents a downstream effector of NADP(H) oxidase and acts as a necessary intermediate step for the hypoxic proliferative response of endothelial cells.  相似文献   
100.
This prospective study was conducted with the aim of examining the efficacy of lowering dialysate calcium (dCa) in order to: (i) stimulate bone turnover in hemodialysis patients with biochemical signs of adynamic bone disease (ABD) (hypercalcemia, normal alkaline phosphatase and intact parathyroid hormone (iPTH) <150 pg/mL); and (ii) diminish hypercalcemia in patients with secondary hyperparathyroidism (sHPT) (hypercalcemia, high alkaline phosphatase and iPTH > 400 pg/mL), thus permitting the use of calcium-containing phosphorus binders and vitamin D metabolites. Patients were divided into: an ABD-treated group (24 patients), a sHPT-treated group (18 patients), an ABD-control group (12 patients) and a sHPT-control group (11 patients). For the ABD- and sHPT-treated patients, hemodialysis was conducted with dCa 1.5 mmol/L for three months and then with dCa 1.25 mmol/L for an additional three months, while in the control groups hemodialysis was conducted with dCa 1.75 mmol/L during the entire study. Reduction of dCa in patients with ABD caused a slight but insignificant decrease of Ca, but a significant and permanent increase of bone-specific alkaline phosphatase and intact parathyroid hormone level serum levels. Reduction of dCa in patients with sHPT slightly but insignificantly decreased Ca and intact parathyroid hormone level values. Nevertheless, this enabled the calcium-based phosphate binder dose to be raised and vitamin D3 metabolites to be introduced. Logistic regression analysis indicated that milder bone disease (both ABD and sHPT) was associated with more the favorable effect of dCa reduction. Thus, low dCa stimulated parathyroid glands and increased bone turnover in ABD patients, and enabled better control of mineral metabolism in sHPT patients.  相似文献   
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