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991.
The clinical management of human brucellosis is still challenging and demands in vitro active antibiotics capable of targeting the pathogen-harboring intracellular compartments. A sustained release of the antibiotic at the site of infection would make it possible to reduce the number of required doses and thus the treatment-associated toxicity. In this study, a hydrophobically modified gentamicin, gentamicin-AOT [AOT is bis(2-ethylhexyl) sulfosuccinate sodium salt], was either microstructured or encapsulated in poly(lactic-co-glycolic acid) (PLGA) nanoparticles. The efficacy of the formulations developed was studied both in vitro and in vivo. Gentamicin formulations reduced Brucella infection in experimentally infected THP-1 monocytes (>2-log10 unit reduction) when using clinically relevant concentrations (18 mg/liter). Moreover, in vivo studies demonstrated that gentamicin-AOT-loaded nanoparticles efficiently targeted the drug both to the liver and the spleen and maintained an antibiotic therapeutic concentration for up to 4 days in both organs. This resulted in an improved efficacy of the antibiotic in experimentally infected mice. Thus, while 14 doses of free gentamicin did not alter the course of the infection, only 4 doses of gentamicin-AOT-loaded nanoparticles reduced the splenic infection by 3.23 logs and eliminated it from 50% of the infected mice with no evidence of adverse toxic effects. These results strongly suggest that PLGA nanoparticles containing chemically modified hydrophobic gentamicin may be a promising alternative for the treatment of human brucellosis.  相似文献   
992.
We analyzed the developmental history of the subplate and related cellular compartments of the prenatal and early postnatal human cerebrum by combining postmortem histological analysis with in vivo MRI. Histological analysis was performed on 21 postmortem brains (age range: 26 postconceptional weeks to 6.5 years) using Nissl staining, AChE-histochemistry, PAS–Alcian blue histochemistry, Gallyas’ silver impregnation, and immunocytochemistry for MAP2, synaptophysin, neurofilament, chondroitin sulfate, fibronectin, and myelin basic protein. The histological findings were correlated with in vivo MRI findings obtained in 30 age-matched fetuses, infants, and children. We analyzed developmental reorganization of major cellular (cell bodies, growing axons) and extracellular (extracellular matrix) components of the subplate and the developing cortex/white matter interface. We found that perinatal and postnatal reorganization of these tissue components is protracted (extending into the second year of life) and characterized by well-delineated, transient and previously undescribed structural and molecular changes at the cortex/white matter interface. The findings of this study are clinically relevant because they may inform and guide a proper interpretation of highly dynamic and hitherto puzzling changes of cortical thickness and cortical/white matter interface as described in current in vivo MRI studies.  相似文献   
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No previous study had applied the modified Wingate rowing test to young athletes (i.e. children and adolescents). The aims of this study were to evaluate the trial-to-trial reliability of a rowing-modified Wingate test in a group of 12–14-year-old rowers (n = 98) and to compare anaerobic power values among the 12-, 13-, and 14-year-old rowers after accounting for differences in physical maturity and body size. Each subject performed two “all-out” 30-s trials on a Concept II rowing ergometer. The trials were separated by a 15-min active recovery period, which included walking and stretching and ensured the participants’ full recovery. The test proved to be highly reliable, with coefficients of variations of 2.4 and 2.9% (CI = 2.1–3.4%) and intraclass correlation coefficients of 0.994 and 0.996 (CI = 0.991–0.997) for mean power and peak power, respectively. The ANCOVA analyses accounting for differences in body size and level of physical maturity (assessed using indices of pubic hair) and the Bonferroni post hoc tests identified the 14-year-olds as having significantly greater adjusted mean power and peak power values (P < 0.01) than the other two age groups, while the differences between the 12- and 13-year-olds in terms of mean power and peak power were not significant. Our findings indicate (1) that the rowing-modified Wingate test may be reliably used for the assessment of specific anaerobic performance in 12–14-year-old rowers and (2) that factors other than physical maturity and body size are partly responsible for the increase in anaerobic power during growth.  相似文献   
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Literature concerning laxative abuse among young women with bulimia is reviewed. Laxative abuse appears to be much more common among females with bulimia than among females who do not meet criteria for bulimia. Patients with bulimia most commonly abuse stimulant-type laxatives. The abuse of laxatives is associated with potentially serious sequellae involving the gastrointestinal tract as well as generalized systemic effects. The different types of laxatives, their mechanisms of action, and the medical complications of laxative abuse are reviewed. Recommendations regarding laxative withdrawal are offered.  相似文献   
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Childhood malnutrition, associated with poor diet, is a clear public health threat in Sri Lanka, with high rates of under‐nutrition and micronutrient deficiencies coupled with the growing risk of overweight/obesity in urban locations. This study explored the dietary diversity and food intake of urban living Sri Lankan preschool children. A cross‐sectional analysis of the baseline data from a cohort study was conducted with parents/caregivers of children aged 2–6 years, from 21 preschool centres in Kurunegala District, Sri Lanka. Demographic and socio‐economic factors, dietary diversity score (DDS) (n = 597) and food intake (n = 458) (using a food frequency questionnaire) were assessed. Children had a mean DDS of 4.56 ± 0·85 out of 9, with most (91.1%) in the medium DDS category (DDS of 3.1–6.0), consuming rice as most common food. Lentils were consumed more than any meat or alternative food groups at all DDS levels. Child DDS differs with parent/caregiver age and ethnicity. Mean daily intakes of fruit (1.02) and vegetables (0.84) servings align with approximately half of national recommendations, with less than 20% of children meeting daily recommendations. More than one‐third consumed sugary snacks and confectionaries daily and 1 in 10 had them twice a day. Around 40% reported watching television while eating the evening meal. Despite the majority having reasonable DDSs (medium category), findings highlighted inadequate intakes of fruits and vegetables, excessive intakes of sugary snacks and unhealthy dietary and social behaviours, suggests the need for population‐based interventions to promote healthier dietary habits.  相似文献   
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