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Toxocara spp. infection and the seroconversion rate in the Amazon have been poorly investigated. This study analyzed individual and household-level risk factors for the presence of IgG antibodies to Toxocara spp. in urban Amazonian children over a period of 7 years and evaluated the seroconversion rates over a 1-year follow-up. In children < 59 months of age, the overall prevalence rate was 28.08% in 2003 and 23.35% in 2010. The 2010–2011 seroconversion rates were 13.90% for children 6–59 months of age and 12.30% for children 84–143 months of age. Multilevel logistic regression analysis identified child age, previous wheezing, and current infection with hookworm as significant associated factors for Toxocara spp. seropositivity in 2003. In 2010, age, previous helminthiasis, and having a dog were associated with seropositivity, whereas having piped water inside the household was a protective factor. Control programs mainly need to target at-risk children, water quality control, and animal deworming strategies.  相似文献   
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The aim of this prospective, randomized, controlled, paired trial was to perform a comparative analysis of the preemptive analgesic effect of nimesulide and tramadol chlorhydrate during third molar surgery. The study was carried out between March and November 2009, involving 94 operations in 47 male and female patients with bilateral impacted lower third molars in comparable positions. The sample was divided into two groups. Group A received an oral dose of 100 mg of nimesulide 1 h prior to surgery. Group B received an oral dose of 100 mg of tramadol chlorhydrate 1 h prior to surgery. The following aspects were evaluated in the postoperative period: adverse effects of the drugs; amount of rescue medication used (acetaminophen 750 mg); and pain 5, 6, 24, 36, 48, 60, 72 and 84 h after surgery using a visual analog pain scale. Peak pain occurred 5 h after surgery in both groups, with a mean pain score of 2.3 in Group A and 3.0 in Group B; this difference did not achieve statistical significance (p > 0.141). Based on the sample studied, nimesulide and tramadol chlorhydrate demonstrate similar preemptive analgesic effects when used in lower third molar surgeries.  相似文献   
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Relapse is associated with a poor prognosis among drug users. Crack cocaine users are more prone to severe dependence because of the intensity of use. Additionally, initiating drug use during adolescence worsens users' prognosis due to the increased rates of impulsivity and other risk behaviors. This study aimed to identify the predictors of early relapse among adolescent crack users discharged from inpatient treatment. A cohort study was conducted with 89 psychiatric inpatients aged 12–17 years from two different hospitals in southern Brazil who met the criteria for crack abuse or dependence. Demographic data, substance use disorders, psychiatric comorbidities, and crack consumption profile were assessed during hospitalization using the Teen Addiction Severity Index, Schedule for Affective Disorders and Schizophrenia for School Age Children—Present and Lifetime, and Crack Consumption Profile. Participants were re-assessed at 1 and 3 months after hospital discharge to determine their crack cocaine use based on self-report, family/caregiver information, and urine tests, whenever possible. There were extremely high rates of relapse (valid percent) in the first and third months, 65.9 and 86.4%, respectively. Statistically significant associations were observed between relapse in the first month and length of cocaine/crack cocaine use, and length of hospital stay. Data at 3 months were not analyzed because of the small number of patients who did not relapse. The high rates and significant associations found in this study suggest that intensive outpatient treatment strategies targeting this population should be developed and implemented to prevent early relapse after detoxification. One of the possible approaches, based on recent studies, might explore motivation as a strategy to reduce the rate of early relapse.  相似文献   
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We report the case of a 47-year-old homeless male with a massive infestation of Pediculus humanus corporis on his entire body. Dermoscopy helped to diagnose pediculosis by showing the involvement of scalp, beard and the genital region in this disease.  相似文献   
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Dengue is currently a major public-health problem. Dengue virus (DENV) is classified into four distinct serotypes, DENV 1-4. After 28 years of absence, DENV-4 was again detected in Brazil in 2010 in Roraima State, and one year later, the virus was identified in the northern Brazilian states of Amazonas and Pará, followed by Rio de Janeiro and São Paulo. In Minas Gerais, the first confirmed case of DENV-4 occurred in the municipality of Frutal in 2011 and has now been isolated from a growing number of patients. Although DENV-2 is associated with the highest risk of severe forms of the disease and death due to the infection, DENV-4 has also been associated with severe forms of the disease and an increasing risk of hemorrhagic manifestations. Herein, the first fatal case of confirmed DENV-4 in Brazil is reported. The patient was an 11-year-old girl from the municipality of Montes Claros in northern Minas Gerais State, Brazil. She had idiopathic thrombocytopenic purpura as a comorbid condition and presented with a fulminant course of infection, leading to death due to hemorrhagic complications. Diagnosis was confirmed by detection of Dengue-specific antibodies using IgM capture enzyme-linked immunosorbent assay and semi-nested RT-PCR. Primary care physicians and other health-care providers should bear in mind that DENV-4 can also result in severe forms of the disease and lead to hemorrhagic complications and death, mainly when dengue infection is associated with coexisting conditions.  相似文献   
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The quest for new antiparasitic alternatives has led researchers to base their studies on insights into biology, host-parasite interactions and pathogenesis. In this context, proteases and their inhibitors are focused, respectively, as druggable targets and new therapy alternatives. Herein, we proposed to evaluate the in vitro effect of the cysteine protease inhibitor E-64 on Giardia trophozoites growth, adherence and viability. Trophozoites (105) were exposed to E-64 at different final concentrations, for 24, 48 and 72 h at 37 °C. In the growth and adherence assays, the number of trophozoites was estimated microscopically in a haemocytometer, whereas cell viability was evaluated by a dye-reduction assay using MTT. The E-64 inhibitor showed effect on growth, adherence and viability of trophozoites, however, its better performance was detected in the 100 µM-treated cultures. Although metronidazole was more effective, the E-64 was shown to be able to inhibit growth, adherence and viability rates by ≥ 50%. These results reveal that E-64 can interfere in some crucial processes to the parasite survival and they open perspectives for future investigations in order to confirm the real antigiardial potential of the protease inhibitors.  相似文献   
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