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61.
Please cite this paper as: Allison et al. (2010) Feasibility of elementary school children’s use of hand gel and facemasks during influenza season. Influenza and Other Respiratory Viruses 4(4), 223–229. Background The feasibility of non-pharmacologic interventions to prevent influenza’s spread in schools is not well known. Objectives To determine the acceptability of, adherence with, and barriers to the use of hand gel and facemasks in elementary schools. Patients and Methods Intervention: We provided hand gel and facemasks to 20 teachers and their students over 4 weeks. Gel use was promoted for the first 2 weeks; mask use was promoted for the second 2 weeks. Outcomes: Acceptability, adherence, and barriers were measured by teachers’ responses on weekly surveys. Mask use was also measured by observation. Results The weekly survey response rate ranged from 70% to 100%. Averaged over 2 weeks, 89% of teachers thought gel use was not disruptive (week 1 – 17/20, week 2 – 16/17), 95% would use gel next winter (week 1 – 19/20, week 2 – 16/17), and 97% would use gel in a pandemic (week 1 – 20/20, week 2 – 16/17). Averaged over 2 weeks, 39% thought mask use was not disruptive (week 1 – 6/17, week 2 – 6/14), 35% would use masks next winter (week 1 – 5/17, week 2 – 6/14), and 97% would use masks in a pandemic (week 1 – 16/17, week 2 – 14/14). About 70% estimated that their students used hand gel ≥4×/day for both weeks (week 1 – 14/20, week 2 – 13/17). Students’ mask use declined over time with 59% of teachers (10/17) estimating regular mask use during week 1 and 29% (4/14) during week 2. By observation, 30% of students wore masks in week 1, while 15% wore masks in week 2. Few barriers to gel use were identified; barriers to mask use were difficulty reading facial expressions and physical discomfort. Conclusions Hand gel use is a feasible strategy in elementary schools. Acceptability and adherence with facemasks was low, but some students and teachers did use facemasks for 2 weeks, and most teachers would use masks in their classroom in a pandemic.  相似文献   
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63.
Children born very prematurely who show intrauterine growth retardation (IUGR) are suggested to be at risk of developing high blood pressure as adults. Renal function may already be impaired by young adult age. To study whether very preterm birth affects blood pressure in young adults, we measured 24-h ambulatory blood pressure (Spacelabs™ 90207 device) and renin concentration in 50 very premature individuals (<32 weeks of gestation), either small (SGA) or appropriate (AGA) for gestational age (21 SGA, 29 AGA), and 30 full-term controls who all were aged 20 years at time of measurement. The mean (standard deviation) daytime systolic blood pressure in SGA and AGA prematurely born individuals, respectively, was 122.7 (8.7) and 123.1 (8.5) mmHg. These values were, respectively, 3.6 mmHg [95% confidence interval (CI) −0.9 to 8.0] and 4.2 mmHg (95% CI 0.4−8.0) higher than in controls [119.6 (7.6)]. Daytime diastolic blood pressure and nighttime blood pressure did not differ between groups. We conclude that individuals born very preterm have higher daytime systolic blood pressure and higher risk of hypertension at a young adult age.  相似文献   
64.
DNA fingerprinting of sister blastomeres from human IVF embryos   总被引:2,自引:0,他引:2  
BACKGROUND: Previously published single cell DNA fingerprinting systems have been plagued by high rates of allele drop-out (ADO) and preferential amplification (PA) preventing clinical application in preimplantation genetic diagnosis. METHODS: Tetranucleotide microsatellite markers with high heterozygosity, known allelic size ranges and minimal PCR stutter artefacts were selected for chromosomes X, 13, 18 and 21 and optimized in a multiplex fluorescent (FL)-PCR format. FL-PCR products were analysed using the ABI Prism 377 DNA sequenator and Genescan software. Validation of the DNA fingerprinting system was performed on single diploid (n = 50) and aneuploid (n = 25) buccal cells and embryonic blastomeres (n = 21). RESULTS: The optimized pentaplex PCR DNA fingerprinting system displayed a high proportion of successful amplifications (>91%) and low ADO and PA (<6%) when assessed on 50 human buccal cells. DNA fingerprints of single cells from a subject with Down's syndrome detected the expected tri-allelic pattern for the chromosome 21 marker, confirming trisomy 21. In a blind study on 21 single blastomeres, all embryos were identifiable by their unique DNA fingerprints and shared parental alleles. CONCLUSIONS: A highly specific multiplex FL-PCR based on the amplification of five highly polymorphic microsatellite markers was developed for single cells. This finding paves the way for the development of a more complex PCR DNA fingerprinting system to assess aneuploidy and single gene mutations in IVF embryos from couples at genetic risk.  相似文献   
65.
CD97 expression is related closely to the dedifferentiation and tumor stage in thyroid carcinomas. We systematically examined the role of CD97 and its closest relative, EMR2, in normal and malignant gastric, esophageal, and pancreatic tissue. The normal tissues were EMR2-, whereas CD97 was expressed slightly in the parietal cells of gastric mucosa and in exocrine pancreatic cells. Interestingly, intralobular and interlobular pancreatic ducts were CD97+. All tumors were EMR2-. CD97 was expressed by 44 of 50 gastric, 14 of 18 pancreatic, and 10 of 13 esophageal carcinomas. Of the 44 gastric cancers, 27 showed disseminated or scattered tumor cells at the invasion front with stronger CD97 expression than tumor cells located in solid tumor formations. There was no correlation between CD97 levels in the tumors or soluble CD97 in the serum samples and the clinicopathologic features of the patients. Taken together, significant numbers of gastric, esophageal, and pancreatic carcinomas are CD97+, whereas its homolog, EMR2, does not have any role in such tumors.  相似文献   
66.
To assess the importance of B cell control of T cell differentiation, we analyzed the course of the T helper type 1 (T(H)1)-driven disease experimental autoimmune encephalomyelitis in mice with an altered B cell compartment. We found that recovery was dependent on the presence of autoantigen-reactive B cells. B cells from recovered mice produced interleukin 10 (IL-10) in response to autoantigen. With a bone marrow chimeric system, we generated mice in which IL-10 deficiency was restricted to B cells but not T cells. In the absence of IL-10 production by B cells, the pro-inflammatory type 1 immune response persisted and mice did not recover. These data show that B cell-derived IL-10 plays a key role in controlling autoimmunity.  相似文献   
67.
Cellular attachment factors like the C-type lectins DC-SIGN and DC-SIGNR (collectively referred to as DC-SIGN/R) can augment viral infection and might promote viral dissemination in and between hosts. The lectin LSECtin is encoded in the same chromosomal locus as DC-SIGN/R and is coexpressed with DC-SIGNR on sinusoidal endothelial cells in liver and lymphnodes. Here, we show that LSECtin enhances infection driven by filovirus glycoproteins (GP) and the S protein of SARS coronavirus, but does not interact with human immunodeficiency virus type-1 and hepatitis C virus envelope proteins. Ligand binding to LSECtin was inhibited by EGTA but not by mannan, suggesting that LSECtin unlike DC-SIGN/R does not recognize high-mannose glycans on viral GPs. Finally, we demonstrate that LSECtin is N-linked glycosylated and that glycosylation is required for cell surface expression. In summary, we identified LSECtin as an attachment factor that in conjunction with DC-SIGNR might concentrate viral pathogens in liver and lymph nodes.  相似文献   
68.
The identification of common genetic variants such as single nucleotide polymorphisms (SNPs) in the human genome has become central in human population genetics and evolution studies, as well as in the study of the genetic basis of complex traits and diseases. Crucial for the accurate identification of genetic variants is the availability of high quality genomic DNA (gDNA). Since popular sources of gDNA (buccal cells, lymphocytes, hair bulb) often do not yield sufficient quantities of DNA for molecular genetic applications, whole genome amplification methods have recently been introduced to generate a renewable source of double-stranded linear DNA. Here, we assess the fidelity of one method, multiple displacement amplification (MDA), which utilizes bacteriophage Phi29 DNA polymerase to generate amplified DNA from an original source of gDNA, in a representative SNP discovery and genetic association study at the melanocortin 1 receptor (MC1R) locus, a highly polymorphic gene in humans involved in skin and hair pigmentation. We observed that MDA has high fidelity for novel SNP discovery and can be a valuable tool in generating a potentially indefinite source of DNA. However, we observed an allele amplification bias that causes genotype miscalls at heterozygous sites. At loci with multiple polymorphic sites in linkage disequilibrium, such as at MC1R, this bias can create a significant number of heterozygote genotype errors that subsequently misrepresents haplotypes.  相似文献   
69.

Background  

Childhood obesity is a substantial public health problem. The extent to which health state preferences (utilities) are related to a child's weight status has not been reported. The aims of this study were (1) to use a generic health state classification system to measure health related quality of life and calculate health utilities in a convenience sample of children and adolescents and (2) to determine the extent to which these measures are associated with weight status and body mass index (BMI).  相似文献   
70.
Pseudomonas chlororaphis phage 201varphi2-1 is a relative of Pseudomonas aeruginosa myovirus phiKZ. Phage 201 phi2-1 was examined by complete genomic sequencing (316,674 bp), by a comprehensive mass spectrometry survey of its virion proteins and by electron microscopy. Seventy-six proteins, of which at least 69 have homologues in phiKZ, were identified by mass spectrometry. Eight proteins, in addition to the major head, tail sheath and tail tube proteins, are abundant in the virion. Electron microscopy of 201 phi2-1 revealed a multitude of long, fine fibers apparently decorating the tail sheath protein. Among the less abundant virion proteins are three homologues to RNA polymerase beta or beta' subunits. Comparison between the genomes of 201 phi2-1 and phiKZ revealed substantial conservation of the genome plan, and a large region with an especially high rate of gene replacement. The phiKZ-like phages exhibited a two-fold higher rate of divergence than for T4-like phages or host genomes.  相似文献   
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