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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   
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ObjectiveTo ascertain antimicrobial susceptibility profile of Proteus mirabilis (P. mirabilis) from clinical urine specimens at a university hospital in the spate of its recorded increasing resistance patterns.MethodsThe study was retrospective in nature. Data generated from urine cultures of patients at University of Calabar Teaching Hospital for a period of five years (2004–2009) were compiled. Relevant information obtained were age and gender of patients, organisms recovered and their antibiotic susceptibility patterns. P. mirabilis was identified using standard laboratory procedures.ResultsP. mirabilis showed the highest resistance against ampicillin, cloxacillin, amoxicillin, tetracycline, co-trimoxazole, erythromycin and chloramphenicol (100%–37.2%) while colistin, ofloxacin, ciprofloxacin, ceftriaxone, nalidixic acid and nitrofurantoin recorded the highest activity (59.1%–96.9%) with no drug recording 100% activity. The resistance of the nosocomial isolates of the organism were significantly higher than the community acquired isolates against that of the common antibiotics in use (P<0.05).ConclusionsExtreme caution should be exercised in antibiotic administration in hospital setting and the potential benefits adequately assessed while control of nosocomial infections be given a priority so as to limit the spread of resistant bacteria.  相似文献   
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ObjectivePoor oral status, represented by partial/complete tooth loss, may lead to changes in food choice, which may ultimately lead to underweight, overweight, or obesity. The aim of this study is to evaluate whether poor oral status is associated with underweight or overweight/obesity, regardless of physical activity.MethodsThis cross-sectional study is part of a major project, The Frailty in Brazilian Elderly Study, carried out in Campinas, Brazil (2008–2009). The sample was composed of 900 independent-living older adults. Complete data were available for 875 individuals including sociodemographic, self-reported amount of medications used and eating difficulty questionnaire, smoking habit, depressive symptoms, physical activity, oral examination, and anthropometric assessments according to the WHO criteria. Body mass index was used as an outcome. Multinomial logistic regression was adjusted for confounding variables.ResultsThe mean age of the sample was 72.7 y (±5.81) and the prevalence of edentulism was 47.7%. Edentate individuals not wearing dentures were more likely to be underweight [odds ratio (OR) = 3.94, 95% confidence interval (CI) 1.14–13.64] and overweight/obese (OR = 2.88, 95%CI 1.12–7.40). Males (OR = 0.56, 95%CI 0.36–0.85) and those not using medications (OR = 0.41 95%CI 0.24–0.70) were less likely to be overweight/obese. Individuals who smoke (OR = 2.62, 95%CI 1.26–5.44) were more likely to be underweight. Older individuals with family income between 3.1 and 5 minimum wage (OR = 1.69, 95%CI 1.00–2.87) were more likely to be overweight/obese.ConclusionTo our knowledge, this is one of the first studies associating poor oral health, represented by edentulism not rehabilitated with dentures, with unfavorable body mass, regardless of the two major confounders, physical activity and depression symptoms.  相似文献   
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Mitogen‐activated protein kinases (MAPKs) regulate normal brain functioning, and their dysfunction is implicated in a number of brain disorders. Thus, there is great interest in understanding the signalling systems that control MAPK functioning. One family of proteins that contribute to this process, the mitogen‐activated protein kinase phosphatases (MKPs), directly inactivate MAPKs through dephosphorylation. Recent studies have identified novel functions of MKPs in foetal development, the immune system, cancer and synaptic plasticity and memory. In the present study, we performed an unbiased investigation using MKP‐2?/? mice to assess whether MKP‐2 plays a global role in modulating brain function. Local cerebral glucose utilization is significantly increased in the ventral tegmental area (VTA) of MKP‐2?/? mice, with connectivity analysis revealing alterations in VTA functional connectivity, including a significant reduction in connectivity to the nucleus accumbens and hippocampus. In addition, spontaneous excitatory postsynaptic current frequency, but not amplitude, onto putative dopamine neurons in the VTA is increased in MKP‐2?/? mice, which indicates that increased excitatory drive may account for the increased VTA glucose utilization. Consistent with modified VTA function and connectivity, in behavioural tests MKP‐2?/? mice exhibited increased sucrose preference and impaired amphetamine‐induced hyperlocomotion. Overall, these data reveal that MKP‐2 plays a role in modulating VTA function and that its dysfunction may contribute to brain disorders in which altered reward processing is present.  相似文献   
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