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131.
132.

Objectives

This study analyzed the oxidative stress status in patients with recurrent aphthous stomatitis (RAS) in the presence and absence of active ulceration.

Material and methods

Oxidative stress was analyzed in peripheral mononuclear cells of 28 RAS patients with active ulceration and 29 controls. A further blood sample was collected from nine subjects randomly selected from the 28 RAS cases, during the period in which the patients did not have active oral ulceration. The reduced glutathione (GSH), malondialdehyde (MDA), and oxidized glutathione (GSSG) levels were measured in these samples.

Results

The mean MDA and GSSG levels were significantly higher in patients with active RAS than in the controls, while GSH was lower in the RAS group (p?p?Conclusions Oxidative stress was detected in our RAS patients.  相似文献   
133.
In order to describe trends in traffic accidents, mortality, vehicle types, fleet sizes, and victims' characteristics in Campinas, S?o Paulo State, Brazil, from 1995 to 2008, this study analyzed vehicle rates, traffic accident rates per inhabitant and per vehicle, case-fatality rates, proportional mortality, mortality rates, and rates ratios. The motorcycle fleet increased 241%. Although the case-fatality rate of motorcycle users from 2000 to 2008 decreased, in 2008 they accounted for 49.3% of fatal accidents on public byways in Campinas. Motorcycles were responsible for the highest run-over rate (66.7 pedestrians/1,000 accidents) and highest pedestrian fatality rate (4 deaths/1,000 accidents). Men showed much higher mortality rates than women. Pedestrian victims were mainly elderly; most vehicle occupants in traffic accidents were in the 15 to 29-year age bracket. From 2006 to 2008, nearly 80% of vehicle users 15 to 39 years of age were motorcyclists. Motorcycle accident prevention should be a priority, using multi-institutional measures.  相似文献   
134.
In the evaluation of particulate matter (PM) toxicity, one faces the challenge of identifying components that could be addressed as markers of toxicity. This study examines the use of statistical methods to determine which components present in the complex mixtures are related to toxic effects. The work is based on data previously published, where we demonstrated that particles collected in different zones of Mexico City showed different ability of inducing cell death, causing DNA damage, or creating proinflammatory effects. Empirically, we correlated those differences to variations in the concentration of transitional metals or endotoxin. In order to test those correlations, in this study we evaluated the role of the concentration of six transitional metals (Ni, V, Zn, Cu, Fe, and Pb) and endotoxin using the following tools: Pearson's regression analysis, correlation matrix between components, and multiple regression followed by a stepwise analysis. Due to collinearity found among several of the components, only Ni, Zn, and Pb were considered as independent variables. Among these, Ni and Zn show better correlations and help to explain the loss in viability, whereas Pb is the component that betters explains the proinflammatory effects. The statistical identification of composition markers facilitates the generation of a hypothesis relating the role played by the composition of PM and its biological effects.  相似文献   
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BACKGROUND: We present a series of 10 patients with osteonecrosis of the jaws (ONJ) that appeared following cancer chemotherapy. MATERIAL AND METHODS: Of the 10 cases with ONJ, six had bone metastases from breast cancers and the other four had multiple myeloma. We analysed the location of bone metastases, as well as the characteristics of the ONJ, and the drugs with which they had been treated for their bone metastases. RESULTS: Of the 10 patients, all had ONJ in the mandible; 50% also had maxillary involvement. The average number of areas of painful exposed was 2.1 per patient (range 1-5). In seven patients a tooth extraction preceded the onset of ONJ. Two patients developed oroantral communications and another a cutaneous fistula to the neck with suppuration. In all the 10 patients the histopatholological diagnosis was of chronic osteomyelitis without evidence of metastatic disease to the jaws. All the patients had received treatment for their malignant bone disease with bisphosphonates. These were the only drugs that all patients had received. CONCLUSION: ONJ appears to have a relationship with the use of bisphosphonates.  相似文献   
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The toxicity of Tityus bahiensis scorpion venom is well known, but there are little data about the damage in offspring of dams that were exposed to the venom during pregnancy. The objective of this work was to determine the toxic effects of venom in adult offspring of Wistar rats exposed to venom in utero. Dams were divided into a control group, subcutaneously injected with saline solution on the 10th (GD10) and 16th (GD16) days, and two experimental groups, subcutaneously injected with venom (2.5 mg/kg) on GD10 or GD16, respectively. Adult offspring were evaluated according to behavioral development and neuronal integrity in the hippocampus. Tests performed in the activity box and in the enriched environment demonstrated that males from GD10 had motor decrease. Females from GD10 showed a depressive-like state and were more anxious, as demonstrated by the forced swimming test and social interaction. The plus-maze discriminative avoidance task demonstrated that GD16 males had lower levels of anxiety. The number of neuronal cells was decreased in CA1, CA3 and CA4 hippocampal areas of males and females from GD10 group and in CA1 of females and CA4 of males from GD16 group. Thus, we conclude that venom exposure in pregnant dams causes subtle alteration in the behavioral and neuronal development of offspring in adult life in a gender-dependent manner.  相似文献   
140.
BACKGROUND: The management of type 2 diabetes mellitus is complicated by the presence of risk factors related to overweight and obesity, particularly visceral adiposity. However, weight loss and weight maintenance are difficult for patients with diabetes, and the benefits of dietary modifications are typically modest. Sibutramine is a serotonin- and norepinephrine-reuptake inhibitor that reduces food intake by inducing early satiety and attenuates the decrease in basal energy expenditure associated with weight loss. Previous trials of sibutramine in overweight and obese patients with type 2 diabetes have shown significant weight loss accompanied by better glycemic control. OBJECTIVE: The goal of this study was to assess the effect on body weight and glycemic control of sibutramine in combination with glibenclamide in obese Hispanic patients with type 2 diabetes. METHODS: This was a 12-month, randomized, double-blind, placebo-controlled clinical trial conducted at the Endocrinology Service, General Hospital of Mexico, Mexico City. Included were overweight or obese (body mass index [BMI] >27 kg/M2) patients with type 2 diabetes between the ages of 24 and 65 years who had been receiving glibenclamide monotherapy for at least 2 weeks and whose glucose concentrations were stable. Patients were randomized to receive sibutramine 10 mg or placebo once daily. The primary efficacy measures were change in body weight, waist circumference, and glycosylated hemoglobin (HbA1c). Anthropometrics and fasting glucose concentrations were measured monthly. HbA1c was determined at baseline and at 6 and 12 months. Laboratory parameters were measured at baseline and at the end of the study. RESULTS: Forty-four patients were randomized to receive sibutramine (28 women, 16 men; mean [SD] age, 47.6 [9.0] years), and 42 were randomized to receive placebo (31 women, 11 men; mean age, 45.8 [8.1] years). Twenty-four patients in the sibutramine group and 23 in the placebo group completed the trial. In the sibutramine group, body weight was reduced from a mean (SD) of 73.9 (10.3) kg at baseline to 69.8 (10.6) kg at month 12; BMI decreased from 29.9 (2.6) to 28.2 (2.9) kg/M2; waist circumference was reduced from 94.9 (8.4) to 90.8 (8.4) cm; the plasma fasting glucose concentration decreased from 140.4 (29.4) to 114.2 (32.0) mg/dL; and the HbA1c value was reduced from 8.9% (1.2) to 8.3% (1.2) (all, P < 0.001). In the placebo group, the corresponding changes were from 74.5 (10.3) kg at baseline to 73.1 (11.2) kg at month 12; from 30.1 (2.5) to 29.5 (2.9) kg/M2; from 94.4 (7.3) to 93.1 (8.3) cm (P < 0.05); from 140.7 (25.2) to 123.9 (38.3) mg/dL (P < 0.05); and from 9.0% (1.2) to 9.1% (1.3). In the sibutramine group, weight loss continued for up to 12 months. CONCLUSION: In this population of obese Hispanic patients with type 2 diabetes, sibutramine combined with glibenclamide therapy achieved weight loss for up to 12 months and was associated with better glycemic control than placebo.  相似文献   
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