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81.
82.

Background

We combined hospital-based surveillance and health utilization survey data to estimate the incidence of respiratory viral infections associated hospitalization among children aged < 5 years in Bangladesh.

Methods

Surveillance physicians collected respiratory specimens from children aged <5 years hospitalized with respiratory illness and residing in the primary hospital catchment areas. We tested respiratory specimens for respiratory syncytial virus, parainfluenza viruses, human metapneumovirus, influenza, adenovirus and rhinoviruses using rRT-PCR. During 2013, we conducted a health utilization survey in the primary catchment areas of the hospitals to determine the proportion of all hospitalizations for respiratory illness among children aged <5 years at the surveillance hospitals during the preceding 12 months. We estimated the respiratory virus-specific incidence of hospitalization by dividing the estimated number of hospitalized children with a laboratory confirmed infection with a respiratory virus by the population aged <5 years of the catchment areas and adjusted for the proportion of children who were hospitalized at the surveillance hospitals.

Results

We estimated that the annual incidence per 1000 children (95% CI) of all cause associated respiratory hospitalization was 11.5 (10–12). The incidences per 1000 children (95% CI) per year for respiratory syncytial virus, parainfluenza, adenovirus, human metapneumovirus and influenza infections were 3(2–3), 0.5(0.4–0.8), 0.4 (0.3–0.6), 0.4 (0.3–0.6), and 0.4 (0.3–0.6) respectively. The incidences per 1000 children (95%CI) of rhinovirus-associated infections among hospitalized children were 5 (3–7), 2 (1–3), 1 (0.6–2), and 3 (2–4) in 2010, 2011, 2012 and 2013, respectively.

Conclusion

Our data suggest that respiratory viruses are associated with a substantial burden of hospitalization in children aged <5 years in Bangladesh.  相似文献   
83.

Purpose

Storage of cultured human oral keratinocytes (HOK) allows for transportation of cultured transplants to eye clinics worldwide. In a previous study, one-week storage of cultured HOK was found to be superior with regard to viability and morphology at 12°C compared to 4°C and 37°C. To understand more of how storage temperature affects cell phenotype, gene expression of HOK before and after storage at 4°C, 12°C, and 37°C was assessed.

Materials and Methods

Cultured HOK were stored in HEPES- and sodium bicarbonate-buffered Minimum Essential Medium at 4°C, 12°C, and 37°C for one week. Total RNA was isolated and the gene expression profile was determined using DNA microarrays and analyzed with Partek Genomics Suite software and Ingenuity Pathway Analysis. Differentially expressed genes (fold change > 1.5 and P < 0.05) were identified by one-way ANOVA. Key genes were validated using qPCR.

Results

Gene expression of cultures stored at 4°C and 12°C clustered close to the unstored control cultures. Cultures stored at 37°C displayed substantial change in gene expression compared to the other groups. In comparison with 12°C, 2,981 genes were differentially expressed at 37°C. In contrast, only 67 genes were differentially expressed between the unstored control and the cells stored at 12°C. The 12°C and 37°C culture groups differed most significantly with regard to the expression of differentiation markers. The Hedgehog signaling pathway was significantly downregulated at 37°C compared to 12°C.

Conclusion

HOK cultures stored at 37°C showed considerably larger changes in gene expression compared to unstored cells than cultured HOK stored at 4°C and 12°C. The changes observed at 37°C consisted of differentiation of the cells towards a squamous epithelium-specific phenotype. Storing cultured ocular surface transplants at 37°C is therefore not recommended. This is particularly interesting as 37°C is the standard incubation temperature used for cell culture.  相似文献   
84.
85.
A highly active and stable nano structured Pt/Mg1-xNixO catalysts was developed by a simple co-precipitation method. The obtained Pt/Mg1-xNixO catalyst exhibited cubic structure nanocatalyst with a size of 50–80 nm and realized CH4 and CO2 conversions as high as 98% at 900°C with excellent stability in the dry reforming of methane. The characterization of catalyst was performed using various kinds of analytical techniques including XRD, BET, XRF, TPR-H2, TGA, TEM, FESEM, FT-IR, and XPS analyses. Characterization of spent catalyst further confirms that Pt/Mg1-xNixO catalyst has high coke-resistance for dry reforming. Thus, the catalyst demonstrated in this study, offers a promising catalyst for resolving the dilemma between dispersion and reducibility of supported metal, as well as activity and stability during high temperature reactions.  相似文献   
86.

Background

Few studies in low-income settings analyse linear growth trajectories from foetal life to pre-adolescence. The aim of this study is to describe linear growth and stunting from birth to 10 years in rural Bangladesh and to analyse whether maternal and environmental determinants at conception are associated with linear growth throughout childhood and stunting at 10 years.

Methods and Findings

Pregnant women participating in the MINIMat trial were identified in early pregnancy and a birth cohort (n = 1054) was followed with 19 growth measurements from birth to 10 years. Analyses of baseline predictors and mean height-for-age Z-scores (HAZ) over time were modelled using GLMM. Logistic regression analysis was used to investigate the associations between baseline predictors and stunting (HAZ<-2) at 10 years. HAZ decreased to 2 years, followed by an increase up to 10 years, while the average height-for-age difference in cm (HAD) to the WHO reference median continued to increase up to 10 years. Prevalence of stunting was highest at 2 years (50%) decreasing to 29% at 10 years. Maternal height, maternal educational level and season of conception were all independent predictors of HAZ from birth to pre-adolescence (p<0.001) and stunting at 10 years. The highest probability to be stunted at 10 years was for children born by short mothers (<147.5 cm) (ORadj 2.93, 95% CI: 2.06–4.20), mothers with no education (ORadj 1.74, 95% CI 1.17–2.81) or those conceived in the pre-monsoon season (ORadj 1.94, 95% CI 1.37–2.77).

Conclusions

Height growth trajectories and prevalence of stunting in pre-adolescence showed strong intergenerational associations, social differentials, and environmental influence from foetal life. Targeting women before and during pregnancy is needed for the prevention of impaired child growth.  相似文献   
87.

Background

Reliable estimates of the burden of multidrug-resistant tuberculosis (MDR-TB) are crucial for effective control and prevention of tuberculosis (TB). Papua New Guinea (PNG) is a high TB burden country with limited information on the magnitude of the MDR-TB problem.

Methods

A cross-sectional study was conducted in four PNG provinces: Madang, Morobe, National Capital District and Western Province. Patient sputum samples were tested for rifampicin resistance by the Xpert MTB/RIF assay and those showing the presence of resistance underwent phenotypic susceptibility testing to first- and second-line anti-TB drugs including streptomycin, isoniazid, rifampicin, ethambutol, pyrazinamide, ofloxacin, amikacin, kanamycin and capreomycin.

Results

Among 1,182 TB patients enrolled in the study, MDR-TB was detected in 20 new (2.7%; 95% confidence intervals [CI] 1.1–4.3%) and 24 previously treated (19.1%; 95%CI: 8.5–29.8%) TB cases. No case of extensively drug-resistant TB (XDR-TB) was detected. Thirty percent (6/20) of new and 33.3% (8/24) of previously treated cases with MDR-TB were detected in a single cluster in Western Province.

Conclusion

In PNG the proportion of MDR-TB in new cases is slightly lower than the regional average of 4.4% (95%CI: 2.6–6.3%). A large proportion of MDR-TB cases were identified from a single hospital in Western Province, suggesting that the prevalence of MDR-TB across the country is heterogeneous. Future surveys should further explore this finding. The survey also helped strengthening the use of smear microscopy and Xpert MTB/RIF testing as diagnostic tools for TB in the country.  相似文献   
88.
This study was undertaken to investigate the development of immature oocytes after their fusion with male somatic cells expressing red fluorescence protein (RFP). RFP‐expressing cells were fused with immature oocytes, matured in vitro and then parthenogenetically activated. Somatic nuclei showed spindle formation, 1st polar body extrusion after in vitro maturation and protruded the 2nd polar body after parthenogenetic activation. RFP was expressed in the resultant embryos; two‐cell stage and blastocysts. Chromosomal analysis showed aneuploidy in 81.82% of the resulting blastocysts while 18.18% of the resulting blastocysts were diploid. Among eight RFP‐expressing blastocysts, Xist mRNAs was detected in six while Sry mRNA was detected in only one blastocyst. We propose “prematuration somatic cell fusion” as an approach to generate embryos using somatic cells instead of spermatozoa. The current approach, if improved, would assist production of embryos for couples where the male partner is sterile, however, genetic and chromosomal analysis of the resultant embryos are required before transfer to the mothers.  相似文献   
89.
90.
The purpose of this study was to investigate the effect of court size on physiological responses and physical performance of young elite basketball players. Twelve male basketball players (18.6 ± 0.5 years; 88.8 ± 14.5 kg; 192.6 ± 6.5 cm) from an under-19 team performed two small-sided games (matches) with different court areas (28x15 m and 28x9 m; 28x15 and 28x9 protocols). The number of players (3x3) was kept the same in each protocol. The players performed a repeated-sprint ability (RSA) test before and after each match. Blood lactate concentration was collected before (pre) and after (post) the matches, and the session rating of perceived exertion (session-RPE) was determined 30 minutes after the match. Best and mean time in the RSA test were not different between the 28x15 and the 28x9 match protocols (p > 0.05). A significant difference was observed for lactate concentration from pre- to post-match (p < 0.05) in both protocols (28x15 and 28x9); however, there was no significant interaction between protocols. A similar session-RPE mean score (28x15: 7.2 ± 1.4 and 28x9: 6.6 ± 1.4) was detected for both protocols (p > 0.05, ES=0.41). In summary, the results of the current study suggest that the different court areas induced similar responses. Although there was no significant difference in effort perception, players tended to perceive a greater effort in the larger court size.  相似文献   
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