152 resultados para second-hand smoke exposure


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Although several reports have demonstrated physiological and behavioral changes in adult rats due to neonatal immune challenges, little is known about their effects in adolescence. Since neonatal exposure to lipopolysaccharide (LPS) alters the neural substrates involved in cognitive disorders, we tested the hypothesis that it may also alter the response to novel environments in adolescent rats. At 3 and 5 days of age, male Wistar rats received intraperitoneal injections of either vehicle solution or E. coli LPS (0.05 mg/kg) or were left undisturbed. In the mid-adolescent period, between 40 and 46 days of age, the rats were exposed to the following behavioral tests: elevated plus-maze, open-field, novel-object exploration task, hole-board and the modified Porsolt forced swim test. The results showed that, in comparison with control animals, LPS-treated rats exhibited (1) less anxiety-related behaviors and enhanced patterns of locomotion and rearing in the plus-maze and the open-field tests, (2) high levels of exploration of both objects in the novel-object task and of corner and central holes in hole-board test, and (3) more time spent diving, an active behavior in the forced swim test. The present findings suggest that neonatal LPS exposure has long-lasting effects on the behavior profile adolescent rats exhibit in response to novelty. This behavioral pattern, characterized by heightened exploratory activity in novel environments, also suggests that early immune stimulation may contribute to the development of impulsive behavior in adolescent rats. (C) 2010 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this work we study the existence and regularity of mild solutions for a damped second order abstract functional differential equation with impulses. The results are obtained using the cosine function theory and fixed point criterions. (C) 2009 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We establish the existence of mild solutions for a class of impulsive second-order partial neutral functional differential equations with infinite delay in a Banach space. (C) 2009 Published by Elsevier Ltd

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work is concerned with implicit second order abstract differential equations with nonlocal conditions. Assuming that the involved operators satisfy sonic compactness properties, we establish the existence of local mild solutions, the existence of global mild solutions and the existence of asymptotically almost periodic solutions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we study the approximate controllability of control systems with states and controls in Hilbert spaces, and described by a second-order semilinear abstract functional differential equation with infinite delay. Initially we establish a characterization for the approximate controllability of a second-order abstract linear system and, in the last section, we compare the approximate controllability of a semilinear abstract functional system with the approximate controllability of the associated linear system. (C) 2008 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We establish existence of mild solutions for a class of abstract second-order partial neutral functional differential equations with unbounded delay in a Banach space.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

P>Background: Mould-attributed symptoms have included features which overlap with unexplained syndromes such as sick building syndrome. Objectives: We describe questionnaire and chart review findings in patients following exposure to moulds which include Stachybotrys and compare responses with two control groups. Methods: Thirty-two patients presented with symptoms attributed to mould exposures. Exposure identification for 25 patients had reported S tachybotrys chartarum as well as other mould (Aspergillus, Penicillium), 88% at work. The remaining seven had professionally visualized or self-reported/photographic exposure evidence only. A chart review was performed and a follow-up with a questionnaire, including questions on current health status, and nonspecific symptoms. Results: Cough, shortness of breath and chest tightness (at presentation) were reported in 79%, 70% and 64%, respectively, and persisted > 6 weeks in 91%. Skin test(s) were positive to fungal extract(s) in 30%. Seventeen returned questionnaires were obtained 3.1 (SD 0.5) years after the initial clinic assessment. Among this subgroup, persisting asthma-like symptoms and symptoms suggestive of sick building syndrome were frequent, and similar to a group previously assessed for darkroom disease among medical radiation technologists. The mould-exposed group more commonly reported they were bothered when walking in a room with carpets, complained of a chemical or metallic taste in their mouth, and had problems in concentration when compared with a control physiotherapist group (P < 0.005). Conclusions: Although only a minority with health concerns from indoor mould exposure had demonstrable mould-allergy, a significant proportion had asthma-like symptoms. Other symptoms were also common and persistent after the initial implicated exposure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The firefighters are at increased risk of respiratory disease as a result of exposure to smoke and dust. The aim of this study was to determine the prevalence and risk associated with respiratory symptoms among city firefighters in Sao Paulo, Brazil. Methods A cross-sectional study utilizing the European Community Respiratory Health Survey (ECRHS) questionnaire was administered to firefighters and police officers, in order to evaluate their respiratory symptoms. Results Complete respiraton, data were obtained from 1,235 firefighters and 1,839 police officers. Among the firefighters, there were 55.5% never-smokers, 22.4% current smokers and 18.2% former smokers (P < 0.05). Among the police officers, there were 63.4%, 18.6%, and 9.6% who were never-smokers, current smokers and former smokers (P < 0.05), respectively. Compared to police, firefighters experienced an increase in wheezing [OR = 1.63 (95% CI: 1.43-1.87)], wheezing with breathlessness [OR = 1.34 (95% CI: 1.10-1.64)], wheezing without a cold [OR = 1.60 (95% CI: 1.32-1.95)], waking with tightness in the chest [OR = 1.20 (95% CI: 1.02-1.42)], and rhinitis [OR = 1.12 (95% CI: 1.03-1.22)]. The prevalence of adult-onset asthma in never-smokers was 9.3% and 6.7% for firefighters and police officers [OR = 1.23 (95% CI: 1.01-1.56)]. All independent association was observed between years employed, smoking, history of rhinitis, and work as a firefighter and respiratory, and nasal symptoms. We observed a high prevalence of asthma-like symptoms in firefighters who presented respiratory symptoms beginning immediately after firefighting. Conclusion These results suggest that the prevalence of respiratory symptoms and asthma in firefighters is higher than those in police officers. Work-as a firefighter, rhinitis and vears employed were risk factors for respiratory,symptoms of asthma. Am. J. Ind. Med. 52:261 269, 2009. (C) 2008 Wiley-Liss, Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Inhaled endotoxin (lipopolysaccharide, LPS) initiates an inflammatory response and leads to the expression of CR3 (CD11b/CD18) receptors on polymorphonuclear leukocytes (PMNs). We determined if PMN activation in nasal lavage fluid (NLF) is a possible biomarker of occupational endotoxin exposure. Seven subjects exposed to endotoxin provided NLF samples that were split into three aliquots (negative control - 1 M nicotinamide; sham; positive control - 11 eta g of exogenous LPS) and PMN activation was measured using a chemiluminometer. Differences in mean PMN activation were apparent, negative control: 548 +/- 15.65 RLU 100 mu l(-1); sham: 11469 +/- 2582 RLU 100 mu l(-1); positive control: 42026 +/- 16659 RLU 100 mu l (n = 7; p < 0.05). This technique shows promise as a diagnostic method for measuring upper airway LPS exposure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Sickle-cell disease is the most prevalent genetic disease in the Brazilian population. Lower limb ulcers are the most frequent cutaneous complications, affecting 8% to 10% of the patients. These ulcers are usually deep and may take many years to heal. Evidence about the effectiveness of systemic or topical treatment of these wounds is limited, apart from stabilization of the anemia. A 28-year old woman with sickle-cell disease was admitted for treatment of three deep chronic lower leg ulcers. All wounds had tendon exposure and contained firmly adherent fibrin slough. Following surgical debridement and before grafting, the wounds were managed with three different dressings: a rayon and normal saline solution dressing, a calcium alginate dressing covered with gauze, and negative pressure therapy. All three wounds healed successfully and their grafts showed complete integration; only the rayon-dressed wound required a second debridement. The alginate and rayon-dressed wounds recurred after 9 months and required additional skin grafts. Helpful research on managing ulcers in patients with sickle-cell disease is minimal, but the results of this case study suggest that topical treatment modalities may affect outcomes. Research to explore the safety and effectiveness of NPT in patients with sickle-cell wounds is warranted.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To explore the hypothesis that air pollution promotes cardiovascular changes, Swiss mice were continuously exposed, since birth, in two open-top chambers (filtered and nonfiltered for airborne particles <= 0.3 mu m) placed 20 m from a street with heavy traffic in downtown Sao Paulo, twenty-four hours per day for four months. Fine particle (PM(2.5)) concentration was determined gravimetrically; hearts were analyzed by morphometry. There was a reduction of the PM(2.5) inside the filtered chamber (filtered = 8.61 +/- 0.79 mu g/m(3), nonfiltered = 18.05 +/- 1.25 mu g/m(3), p < .001). Coronary arteries showed no evidence of luminal narrowing in the exposed group but presented higher collagen content in the adventitia of LV large-sized and RV midsized vessels (p = .001) and elastic fibers in both tunicae adventitia and intima-media of almost all sized arterioles from both ventricles (p = .03 and p = .001, respectively). We concluded that chronic exposure to urban air since birth induces mild but significant vascular structural alterations in normal individuals, presented as coronary arteriolar fibrosis and elastosis. These results might contribute to altered vascular response and ischemic events in the adulthood.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: To evaluate the prevalence of chronic autoimmune thyroiditis (CAT) and iodine-induced hypothyroidism, hyperthyroidism (overt and subclinical). and goiter in a population exposed to excessive iodine intake for 5 years (table salt iodine concentrations: 40-100 mg/kg salt). Design: This was a population-based, cross-sectional study with 1085 participants randomly selected from a metropolitan area in Sao Paulo, Brazil, and conducted during the first semester of 2004. Methods: Thyroid ultrasound examination was performed in all participants and samples of urine and blood were collected from each subject. Serum levels of thyroid-stimulating hormone, free thyroxine, and anti-thyroid peroxidase (TPO) antibodies, urinary iodine concentration. thyroid volume, and thyroid echogenicity were evaluated. We also analyzed table salt iodine concentrations. Results: At the time the study was conducted, table salt iodine concentrations were within the new official limits (20-60 mg/kg salt). Nevertheless, in 45.6%, of the participants, urinary iodine excretion was excessive (above 300 mu g/l) and, in 14.1%, it was higher than 400 mu g/l. The prevalence of CAT (including atrophic thyroiditis) was 16.9% (183/1085), women were more affected than men (21.5 vs 9.1% respectively, P=0.02). Hypothyroidism was detected in 8.0%, (87/1085) of the Population with CAT. Hyperthyroidism was diagnosed in 3.3% of the individuals (36/1085) and goiter was identified in 3.1% (34/1085). Conclusions: Five years of excessive iodine intake by the Brazilian population may have increased the prevalence of CAT and hypothyroidism in subjects genetically predisposed to thyroid autoimmune diseases. Appropriate screening for early detection of thyroid dysfunction may be considered during excessive nutritional iodine intake.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study aimed to verify the time course of the effects of environmental levels of urban air pollution toxicity on lung arterioles. BALB/c mice (n = 56) were continuously exposed to selective chambers equipped with (filtered, F) or without (non-filtered, NF) filter devices for particles and toxic gases for 24 h/day, over 14, 21, 30 or 45 days. After exposure, we evaluated the lumen-wall relationship (an estimator of arteriolar narrowing), endothelial nitric oxide synthase (eNOS) and endothelin type A receptor (ETAr) expression in the vascular wall and inflammatory influx of the peribronchiolar area. Concentrations of fine particulate matter (PM <= 2.5 mu g/m(3)), nitrogen dioxide (NO(2)), black smoke (BS), humidity and temperature in both the environment and inside the chambers were measured daily. Filters cleared 100% of BS and 97% of PM inside the F chamber. The arteriole wall of the lungs of mice from NF chamber had an increased ETAr expression (p <= 0.042) concomitant to a decrease in the lumen/wall ratio (p = 0.02) on the early days of exposure, compared to controls. They also presented a progressive increment of inflammatory influx in the peribronchiolar area during the study (p = 0.04) and decrement of the eNOS expression on the 45th day of exposure in both vascular layers (p <= 0.03). We found that after 14 days of exposure, the ambient levels of air pollutants in Sao Paulo induced vasoconstriction that was associated with an increase in ETAr expression. These vascular results do not appear to be coupled to the progressive inflammatory influx in lung tissue, suggesting a down-regulation of vasoconstrictive mechanisms through an imbalance in the cytokines network. It is likely that these responses are protective measures that decrease tissue damage brought about by continuous exposure to air pollutants. (C) 2010 Elsevier Inc. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We analyzed the impact of chronic exposure to urban air pollution on the development of atherosclerosis. Hyperlipemic mice (LDLR(-/-)) were submitted to a high fat diet and air pollution for four months. We measured the susceptibility of LDL to oxidative modifications (TBARS), the presence of anti-oxLDL and an apoB-derived peptide (apoB-D) in blood and the degree of atherosclerosis in the aortic arch. Air pollution increased the susceptibility of LDL to oxidation as well as anti-oxLDL and anti-apo-B levels. These levels were even higher than in mice submitted to a high fat diet and non-polluted air. The lipid content of the atherosclerotic plaques in the aorta was increased in groups with a high cholesterol diet independently of the air quality. However, the thickness of the arterial wall was greater in mice fed a high lipid diet with polluted air. Thus, we conclude that urban air pollution exacerbates the susceptibility of LDL to oxidation, atherogenesis and vascular remodeling in hyperlipemic mice and that an immune response accompanies this process. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of this study was to evaluate the mid- and long-term results of percutaneous transhepatic cholangiography (PTC) and biliary drainage in children with isolated bilioenteric anastomotic stenosis (BAS) after pediatric liver transplantation. Sixty-four children underwent PTC from March 1993 to May 2008. Nineteen cholangiograms were normal; 10 showed intrahepatic biliary stenosis and BAS, and 35 showed isolated BAS. Cadaveric grafts were used in 19 and living donor grafts in 16 patients. Four patients received a whole liver, and 31 patients received a left lobe or left lateral segment. Roux-en-Y hepaticojejunostomy was performed in all patients. Indication for PTC was based on clinical, laboratory, and histopathologic findings. In patients with isolated BAS, dilation and biliary catheter placement, with changes every 2 months, were performed. Patients were separated into 4 groups according to number of treatment sessions required. The drainage catheter was removed if cholangiogram showed no significant residual stenosis and normal biliary emptying time after a minimum of 6 months. The relationship between risk factors (recipient`s weight < 10 kg, previous exposure to Cytomegalovirus, donor-recipient sex and weight relations, autoimmune disease as indication for transplantion, previous Kasai`s surgery, use of reduced liver grafts, chronic or acute rejection occurrence) and treatment was evaluated. Before PTC, fever was observed in 46%, biliary dilation in 23%, increased bilirubin in 57%, and increased gamma-glutamyltransferase (GGT) in 100% of patients. In the group with BAS, 24 of 35 (69%) patients had histopathologic findings of cholestasis as did 9 of 19 (47%) patients in the group with normal PTC. Of the 35 patients, 23 (65.7%) needed 1 (group I), 7 needed 2 (group II), 4 needed 3 (group III), and 1 needed 4 treatment sessions (group IV). The best results were observed after 1 treatment session, and the mean duration of catheter placement and replacement was 10 months. The primary patency rate was 61.2%, and the recurrence rate was 34.3% (group I). Seven patients (7 of 35; 20%) had their stricture treated with a second treatment session (group II). The average drainage time in group II was 24 months. During a period > 20 months, 4 patients (4 of 35; 11.4%) required 1 additional treatment session (group III), and 1 patient (1 of 35; 2.9%) had a catheter placed at the end of the study period (group IV). Drainage time in group I was significantly shorter than those in groups II, III, and IV (p < 0.05). There was no statistically significant relation between therapeutic response and the selected risk factors (p > 0.05). The majority of complications, such as catheter displacement and leakage, were classified as minor; however, 2 patients (5.7%) with hemobilia were noted. Complications increased according to the need for reintervention. In conclusion, balloon dilation and percutaneous drainage placement is safe and effective, and it has long-term patency for children with BAS after liver transplantation. Because of prolonged treatment time, reintervention may be necessary, thereby increasing the complication rate. Balloon dilation and percutaneous drainage placement should be considered as the first treatment option because of its minimally invasive nature.