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1.
BACKGROUND: Identify risk factors for asthma in adolescents from S?o Paulo, Brazil. METHODS: total of 528 adolescents (141 asthmatics, 387 control subjects) from the ISAAC study (phase III) were submitted to a complementary questionnaire to evaluate risk factors, through response to questions regarding personal history, environment, and diet and an agreement to undergo the skin prick test (SPT) for aeroallergens. RESULTS: Positive SPT to at least one allergen occurred in 49.4% adolescents. The risk factors for asthma were: prematurity (OR: 3.84, 95% CI: 1.54-9.64), rhinitis (OR: 3.18, 95% CI: 1.71-5.91), positivity in the SPT (OR: 2.81, 95% CI: 1.48-5.32), eczema in characteristic skin-folds (OR: 2.86, 95% CI: 1.13-7.26), and an allergic mother (OR: 2.01, 95% CI: 1.02-3.93). The consumption of cooked vegetables was a protective factor for asthma (OR: 0.37, 95% CI: 0.18-0.79) CONCLUSIONS: Asthma is a multifatorial disease. An allergic mother, aeroallergen sensitization, rhinitis, eczema and prematurity were considered risk factors and the consumption of cooked vegetables was considered a protective factor for asthma in this population.  相似文献   
2.
In this report, we describe an investigation of the effects of Lutzomyia longipalpis sand fly salivary gland homogenates (SGH) on cytokine production and expression of costimulatory molecules on human monocytes, macrophages (Ms), and dendritic cells (DCs). SGH of L. longipalpis induced an increase in interleukin-6 (IL-6), IL-8 and IL-12p40 production but a decrease in tumor necrosis factor alpha and IL-10 production by lipopolysaccharida (LPS)-stimulated monocytes. We also examined the expression of costimulatory molecules on the surface of monocytes, Ms, and DCs. Whereas SGH affected the expression of these molecules on monocytes and Ms, it had little effect on these molecules on DCs. However, when DCs were generated from human monocytes in the presence of SGH, SGH inhibited the expression of costimulatory molecules. In addition, a decrease in the maturation of DCs induced by CD40L was observed in the presence of SGH. Finally, preincubating SGH with human sera containing anti-SGH-specific antibodies abolished the effects of SGH on cytokine production by LPS-stimulated monocytes.  相似文献   
3.
Asthma and rhinitis epidemiology has wide variations around the world. The aim of this review was verify the prevalence of asthma and rhinitis in South America and report differences from other regions of the world. We reviewed studies with International Study of Asthma and Allergies in Childhood (ISAAC) methodology in South America, Phases I and III. In South America the ISAAC Phase I ranked four countries among top ten in prevalence of asthma and three countries among top ten in prevalence of rhinoconjunctivitis. ISAAC Phase III showed little changes in asthma and rhinitis prevalence in South American countries. The prevalence increases of asthma and rhinitis in South American centers indicate that the burden of both is continuing to rise, but the differences in prevalence are lessening.  相似文献   
4.
Objective:To identify changes in the prevalence and severity of recurrent wheezing (RW) in infants using data obtained from two surveys administered seven years apart. Methods: A cross-sectional, international, population-based study in infants aged 12–15 months was conducted. Data were obtained from two surveys (S1 and S2, in 2005 and 2012, respectively) using the same methodology in three large Latin American cities: Curitiba (Brazil), São Paulo (Brazil), and Santiago (Chile). Results: A decrease in the overall prevalence of RW was identified between S1 (23.3%) and S2 (20.4%), p = 0.004, but it was mainly driven by the reduction observed in São Paulo; in Curitiba and Santiago, this change was not significant. The mean prevalence of the following RW severity indicators remained high and stable: severe wheezing episodes (56.9% in S1 and 54.2% in S2, p = 0.32) and emergency department (ED) visits for wheezing (S1 = 68.1%, S2 70.9%, p = 0.21). A significant increase in admissions for wheezing (21.1% to 26.7%, p = 0.004) was observed. In Curitiba and São Paulo, there were significant increases in the prevalence of physician-diagnosed asthma and in the use of inhaled corticosteroids and oral antileukotrienes. Conclusions: The prevalence and severity of RW during the first year of life remained high over time, with remarkably high rates of ED visits, admissions for wheezing and use of asthma medications. This study suggests the need for considering early asthma diagnosis and to establish an appropriate treatment in infants with recurrent and severe asthma-like symptoms.  相似文献   
5.
ObjectiveTo assess speech alterations in mouth-breathing children, and to correlate them with the respiratory type, etiology, gender, and age.MethodA total of 439 mouth-breathers were evaluated, aged between 4 and 12 years. The presence of speech alterations in children older than 5 years was considered delayed speech development. The observed alterations were tongue interposition (TI), frontal lisp (FL), articulatory disorders (AD), sound omissions (SO), and lateral lisp (LL). The etiology of mouth breathing, gender, age, respiratory type, and speech disorders were correlated.ResultsSpeech alterations were diagnosed in 31.2% of patients, unrelated to the respiratory type: oral or mixed. Increased frequency of articulatory disorders and more than one speech disorder were observed in males. TI was observed in 53.3% patients, followed by AD in 26.3%, and by FL in 21.9%. The co-occurrence of two or more speech alterations was observed in 24.8% of the children.ConclusionMouth breathing can affect speech development, socialization, and school performance. Early detection of mouth breathing is essential to prevent and minimize its negative effects on the overall development of individuals.  相似文献   
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7.
The objective of this work was to evaluate photodynamic therapy (PDT) by using a hematoporphyrin derivative as a photosensitizer and light-emitting diodes (LEDs) as light source in induced mammary tumors of Sprague–Dawley (SD) rats. Twenty SD rats with mammary tumors induced by DMBA were used. Animals were divided into four groups: control (G1), PDT only (G2), surgical removal of tumor (G3), and submitted to PDT immediately after surgical removal of tumor (G4). Tumors were measured over 6 weeks. Lesions and surgical were LEDs lighted up (200 J/cm2 dose). The light distribution in vivo study used two additional animals without mammary tumors. In the control group, the average growth of tumor diameter was approximately 0.40 cm/week. While for PDT group, a growth of less than 0.15 cm/week was observed, suggesting significant delay in tumor growth. Therefore, only partial irradiation of the tumors occurred with a reduction in development, but without elimination. Animals in G4 had no tumor recurrence during the 12 weeks, after chemical induction, when compared with G3 animals that showed 60 % recurrence rate after 12 weeks of chemical induction. PDT used in the experimental model of mammary tumor as a single therapy was effective in reducing tumor development, so the surgery associated with PDT is a safe and efficient destruction of residual tumor, preventing recurrence of the tumor.  相似文献   
8.
Finding a better first antiretroviral regimen is one of the strategies used to improve span and quality of life of HIV/AIDS patients. 891 patients were followed during 24 months or until interruption/abandonment of treatment, changing regimen or death. At the end of 6 months, 69% of the patients were still being treated with the first regimen, 54% at 12 months, 48% at 18 months and 39% at 24 months. AZT-3TC-EFV was the most prescribed regimen and with the lesser discontinuation. NNRTI regimens showed high effectiveness and durability compared to PI regimens. Irregular medication dispensation was the only risk factor for failure/interruption of treatment in multivariate analyses. Intolerance/adverse effects were mainly responsible for first regimen discontinuation, followed by abandonment/non-adherence and virologic failure. Results showed significant difference between causes of interruption of first HAART with higher percentage of intolerance/adverse effects with PI regimens and higher immunologic failure with NNRTI regimens. Even with the availability of more potent and tolerable drugs, lack of adherence to HAART and high level of adverse effects are still the most important barriers to prolonged success of treatment. This study adds relevant information about durability and effectiveness of HAART in the first decade of its use in Brazil.  相似文献   
9.
The purpose of this retrospective study was to associate the amount of keratinized gingiva present in adolescents prior to orthodontic treatment to the development of gingival recessions after the end of treatment. The sample consisted of the intra-oral photographs and orthodontic study models from 209 Caucasian patients with a mean age of 11.20 +/- 1.83 years on their initial records and 14.7 +/- 1.8 years on their final records. Patients were either Angle Class I or II and were submitted to non-extraction orthodontic treatment. Gingival recession was evaluated by visual inspection of the lower incisors and canines as seen in the initial and final study models and intra-oral photographs. The amount of recession was quantified using a digital caliper and the observed post-treatment gingival margin alterations were classified as unaltered, coronal migration of the gingival margin or apical migration of the gingival margin. The width of the keratinized gingiva was measured from the mucogingival line to the gingival margin on the pre-treatment photographs. The teeth that developed gingival recession and those that did not have their gingival margin position changed did not differ in relation to the initial amount of keratinized gingiva (3.00 +/- 0.61 and 3.5 +/- 0.86 mm, respectively). Paradoxically, teeth that presented a coronal migration of the gingival margin had a smaller initial amount of keratinized gingiva (2.26 +/- 0.31 mm). The mean amount of initial keratinized gingiva did not predispose lower incisors and canines to gingival recession.  相似文献   
10.
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