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81.
BACKGROUND: Public places, including schools, have been identified as sources of exposure to allergens derived from mites, cockroach, cat, and dog and to endotoxin. OBJECTIVES: The purposes of this study were to assess and compare exposure to allergens and endotoxin in 4 types of public child-care facilities in Brazil and to investigate whether the presence of children and the performance of cleaning procedures could have an influence on allergen and endotoxin levels. METHODS: We have analyzed dust from bedding, floors, chairs, and tables of daycare centers (DCs), preschools, kindergartens, and elementary schools (ESs). Major allergens from mites, cockroach, cat, and dog were quantitated by means of ELISA, and endotoxin content was determined by using the Limulus Amebocyte Lysate assay. RESULTS: Group 1 mite allergens were greater than 2 microg/g in 67% of DC and preschool samples and in 8.9% and 2.2% of kindergarten and ES samples, respectively. The presence of bedding in DCs and preschools accounted for increased levels of mite allergens in these settings. Levels of Bla g 1 were higher in ES floors compared with those found in DC and preschool floors. Low levels (<1 microg/g) of Fel d 1 e Can f 1 were found in most samples. Levels of endotoxin in DCs and preschools were 3 times higher than in ESs. CONCLUSIONS: DCs and schools in Brazil should be considered as important sources of exposure to dust mites and cockroach allergens and to endotoxin. Recommendations for mite allergen avoidance should include appropriate care of bedding in DCs and preschools.  相似文献   
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Photodynamic therapy (PDT) has been used for local treatment of several types of tumors. Light penetration of biological tissue is one limiting factor in PDT, decreasing the success rates of the treatment of invasive and solid tumors. In those cases, a possible solution is to use interstitial PDT, in which both diffuser optical fibers are inserted into the tumor. The uniformity of the diffuser emission plays a crucial role in planning the delivery of the appropriate light fluence and in ensuring treatment success. In this study, we characterized a diffuser optical fiber concerning its homogeneity. We showed that the diffuser emission can be inhomogeneous and that the necrosis generated by interstitial PDT using such a diffuser for illumination is asymmetrical in volume as a result. This observation has relevant consequences in achieving success in PDT and phototherapies in general, as the delivered light fluence depends on adequate previous knowledge of the irradiation profile.  相似文献   
84.

Objective

To identify factors associated with total sedentary time and screen time in children aged 9–11 years.

Methods

For seven consecutive days, 328 children (51.5% boys) used accelerometers to monitor total sedentary time. Screen time was calculated by the self-reporting method. Individual, family, family environment, and school environment questionnaires were filled out. Body composition was measured using a Tanita scale.

Results

The mean sedentary time was 500 min/day (boys: 489, girls: 511, p = 0.005), and mean screen time was 234 min/day (boys: 246, girls: 222, p = 0.053). In both genders, factors associated with sedentary time were healthy dietary pattern and moderate-to-vigorous physical activity. In boys, only moderate-to-vigorous physical activity was significant; in girls, the healthy dietary pattern, moderate-to-vigorous physical activity, and transportation to school were significant. As for the screen time, the associated factors were body mass index and healthy dietary pattern (both genders). In boys, the associated factors were body mass index, healthy dietary pattern, and television in the bedroom. In girls, the associated factors were healthy dietary pattern, transportation to school, and physical activity policies or practice at school.

Conclusion

Several associated factors were identified in the association between total sedentary time and screen time in children; however, only the healthy dietary pattern was common between sedentary time and screen time.  相似文献   
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The question of whether HIV-1 RNA in cerebrospinal fluid (CSF) is derived from viral replication in the central nervous system or simply reflects the transit of infected lymphocytes from the blood compartment has long been a matter of debate. Some studies found no correlation between CSF and plasma viral load, whereas others did. The lack of a correlation between the two compartments suggests that the presence of HIV-1 RNA is not simply due to the passive passage of the virus from blood to CSF but rather due to intrathecal replication. To evaluate the correlation between plasma and CSF HIV-1 RNA levels and to identify situations in which there is no correlation between the two compartments, seventy patients were prospectively studied. The association between CSF and plasma viral load was evaluated in the total population and in subgroups of patients with similar characteristics. A correlation between the CSF and plasma compartments was observed for patients undergoing highly active antiretroviral therapy (HAART), those with a CD4 T lymphocyte count lower than 200 cells/mm3, and those with increased CSF protein content. On the other hand, no correlation was observed for patients without adequate virological control, who had a CD4 count higher than 200 cells/mm3 and who did not use HAART. The correlation between the two compartments observed in some patients suggests that CSF HIV-1 RNA levels may reflect plasma levels in these subjects. In contrast, the lack of a correlation between the two compartments in patients who were not on HAART and who had normal CSF proteins and a poor virological control possibly indicates compartmentalization of the virus in CSF and, consequently, plasma-independent intrathecal viral replication.  相似文献   
87.

OBJECTIVES:

The aims of the Online Latin American Survey of Anaphylaxis (OLASA) were to identify the main clinical manifestations, triggers, and treatments of severe allergic reactions in patients who were seen by allergists from July 2008 to June 2010 in 15 Latin American countries and Portugal (n = 634).

RESULTS:

Of all patients, 68.5% were older than 18 years, 41.6% were male, and 65.4% experienced the allergic reaction at home. The etiologic agent was identified in 87.4% of cases and predominantly consisted of drugs (31.2%), foods (23.3%), and insect stings (14.9%). The main symptom categories observed during the acute episodes were cutaneous (94.0%) and respiratory (79.0%). The majority of patients (71.6%) were treated initially by a physician (office/emergency room) within the first hour after the reaction occurred (60.2%), and 43.5% recovered in the first hour after treatment. Most patients were treated in an emergency setting, but only 37.3% received parenteral epinephrine alone or associated with other medication. However, 80.5% and 70.2% were treated with corticosteroids or antihistamines (alone or in association), respectively. A total of 12.9% of the patients underwent reanimation maneuvers, and 15.2% were hospitalized. Only 5.8% of the patients returned to the emergency room after discharge, with 21.7% returning in the first 6 hours after initial treatment.

CONCLUSION:

The main clinical manifestations of severe allergic reactions were cutaneous. The etiologic agents that were identified as causing these acute episodes differed according to age group. Following in order: drugs (31.2%), foods (23.3% and insect stings (14.9%) in adults with foods predominance in children. Treatment provided for acute anaphylactic reactions was not appropriate. It is necessary to improve educational programs in order to enhance the knowledge on this potentially fatal emergency.  相似文献   
88.
The aim of the present retrospective study was to evaluate the influence of age and gender on upper and lower airway width and upper lip length. In this study, 390 lateral cephalograms were divided into 13 age groups (ranging from 6 to 18 years) and were analyzed. The intergroup differences were analyzed using a MANOVA (Multivariate Analysis of the Variance), and the intragroup differences were analyzed using an ANOVA (Analysis of the Variance) and Tukey's test. The results of the present study indicated that although the airway width and the upper lip length increased with age, the lower airway width exhibited variable growth between the ages of six and eighteen years. The airway width was significantly greater in females than males, whereas the upper airway width was similar between these two genders. The lip length was significantly shorter in females than males. The lower airway width and upper lip length were significantly different between males and females, whereas the upper airway width was similar for the genders. The upper airway width and upper lip exhibited incremental growth between the ages of six and eighteen years. The upper lip closely followed the growth pattern of the upper airway width; the growth plateaued between the ages of 6 and 9 years, increased from 9 to 16 years and plateaued from 16 to 18 years.  相似文献   
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