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11.

Objectives

To determine the burden and molecular epidemiology of rotavirus gastroenteritis in children hospitalized with severe acute watery diarrhea in Pakistan prior to introduction of rotavirus vaccine.

Methods

A cross-sectional study was carried out over a period of two years from 2006 – 2008 at five sentinel hospitals in the cities of Karachi, Lahore, Rawalpindi, and Peshawar. Stool samples collected from children under five years of age hospitalized with severe acute watery diarrhea were tested for rotavirus antigen via enzyme immunoassay (EIA) (IDEA REF K6020 Oxoid Ltd (Ely), Cambridge, United Kingdom). A subset of EIA positive stool samples were further processed for genotyping.

Results

6679 children were enrolled and stool specimens of 2039 (30.5%) were positive for rotavirus. Rotavirus positivity ranged from 16.3% to 39.4% in the 5 hospitals with highest positivity in Lahore. 1241 (61%) of all rotavirus cases were in infants under one year of age. Among the strains examined for G-serotypes, the occurrence of G1, G2, G9 and G4 strains was found to be 28%, 24%, 14% and 13%, respectively. Among P-types, the most commonly occurring strains were P6 (31.5%) followed by P8 (20%) and P4 (12%). Prevalent rotavirus genotype in hospitalized children of severe diarrhea were G1P[8] 11.6% (69/593), followed by G2P[4] 10.4% (62/593), and G4P[6] 10.1% (60/593).

Conclusions

Approximately one third of children hospitalized with severe gastroenteritis in urban centers in Pakistan have rotavirus. Introduction of rotavirus vaccine in Pakistan''s national immunization program could prevent many severe episodes and diarrheal deaths.  相似文献   
12.
Mutations in the coding region of the methyl-CpG-binding protein 2 ( MECP2) gene cause Rett syndrome and have also been reported in a number of X-linked mental retardation syndromes. Furthermore, such mutations have recently been described in a few autistic patients. In this study, a large sample of individuals with autism was screened in order to elucidate systematically whether specific mutations in MECP2 play a role in autism. The mutation analysis of the coding sequence of the gene was performed by denaturing high-pressure liquid chromatography and direct sequencing. Taken together, 14 sequence variants were identified in 152 autistic patients from 134 German families and 50 unrelated patients from the International Molecular Genetic Study of Autism Consortium affected relative-pair sample. Eleven of these variants were excluded for having an aetiological role as they were either silent mutations, did not cosegregate with autism in the pedigrees of the patients or represented known polymorphisms. The relevance of the three remaining mutations towards the aetiology of autism could not be ruled out, although they were not localised within functional domains of MeCP2 and may be rare polymorphisms. Taking into account the large size of our sample, we conclude that mutations in the coding region of MECP2 do not play a major role in autism susceptibility. Therefore, infantile autism and Rett syndrome probably represent two distinct entities at the molecular genetic level.  相似文献   
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The cell-free extracts from animal Xenopus laevis egg could induce chromatin decon-densation and pronuclear formation from demembranated plant (Orychophragmus violaceus) sperm. The demembranated Orychophragmus violaceus sperm began to swell in 30 min incubation, and then were gradually decondensed. The reassembly of nuclear envelope in the reconstituted nuclei had been visualized by means of electron microscopy and fluorescent microscopy. Membrane vesicles fused to form the double envelope around the periphery of the decondensed chromatin. The morphology of the newly formed nucleus, with a double membrane, was similar to those nuclei after fertilization. Transmission electron microscope micrograph of the whole mount prepared nuclear matrix-lamina showed the reconstituted nucleus to be filled with a dense network.  相似文献   
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Institutionalized older people are prone to oral health problems and their negative impact due to frailty, disabilities, multi-morbidity, and multiple medication use. Until recently, no evidence-based oral health care guideline for institutionalized older people has been available. For that reason, the Dutch Association of Nursing Home Physicians developed the Oral health care Guideline for Older people in Long-term care Institutions (OGOLI), meeting the requirements of the AGREE instrument for assessing a guideline's quality. This short report presents the keynotes and the content of the Oral health care Guideline. Most recommendations are based on expert opinions. Only 4 recommendations (education, pneumonia, use of an electric toothbrush, and fluoride rinsing in case of a sudden increase of oral plaque amount) are based on evidence level A2 conclusions. This emphasizes the need for further research on oral health of institutionalized older people.  相似文献   
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To assist community planners in allocating scarce resources in a mass casualty event, the Department of Health and Human Services' Agency for Healthcare Research and Quality (AHRQ) and the Office of the Assistant Secretary for Preparedness and Response collaborated with leading experts on a series of issue papers on preparedness and response. These papers were presented at an expert meeting in Washington, DC, in June 2006. The papers, revised based on meeting discussions, have been published by AHRQ as Mass Medical Care with Scarce Resources: A Community Planning Guide.  相似文献   
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