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51.

Background

Inadequate volumes of physical activity may be associated with the increases in inappropriately high weight in children of 5 years of age and younger. Preschools have typically lacked sufficient time in daily physical activity.

Purpose

A preschool-administered physical activity treatment based on social cognitive and self-efficacy theory (Start For Life) was tested for its association with increased physical activity and reduced body mass index (BMI).

Methods

Data from accelerometer and BMI assessments over a 9-month preschool year (18 treatment and 8 control classes of 17 to 20 children each; mean age?=?4.4 years) were used to contrast the behaviorally based treatment of 30 min per day with a usual care condition of the same duration. The sample was primarily African-American. Preschool teachers administered all processes.

Results

The Start For Life treatment was associated with a significantly greater percentage of the preschool day in moderate-to-vigorous and vigorous physical activity (approximately 30 min per week more), with sedentary time unaffected. The treatment was also associated with a significant reduction in BMI, with effect sizes greatest in overweight and obese children.

Conclusions

Although results were positive in contrast to usual care and other related interventions, the specific sample requires that the Start For Life treatment undergo sufficient replication to increase confidence in generalizability of the findings to others. Although reduction in sedentary time may require a different strategy, the practical application of the present treatment suggests possibilities for addressing overweight through increasing moderate-to-vigorous physical activity in preschool settings.  相似文献   
52.
53.
Purified CD34+ Lin- Thy+ stem cells do not contain clonal myeloma cells   总被引:6,自引:0,他引:6  
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly.  相似文献   
54.
Molecular heterogeneity in acute leukemia lineage switch   总被引:1,自引:0,他引:1  
Six cases of acute leukemia that underwent lineage switch from acute lymphocytic leukemia to acute myelogenous leukemia are reported. The mean age of the patients was 24 years, time to conversion was 36 months, and survival after conversion was only 3 months. Of the three cases which showed abnormal metaphases at both diagnosis and conversion, two (cases 2, 5) showed related cytogenetic abnormalities, and the third showed (case 3) independent chromosomal changes. Molecular analysis for immunoglobulin heavy chain and T-cell receptor beta chain genes showed that five of the six cases had rearrangement of at least one of these lymphoid associated genes at conversion to acute myelogenous leukemia. The single case (case 3) in which there were no lymphoid gene rearrangements at conversion was also the only case in which independent karyotypic abnormalities at diagnosis and conversion were demonstrated. Our findings suggest that lineage switch can represent either relapse of the original clone with heterogeneity at the molecular level or the emergence of a second new leukemic clone without molecular heterogeneity.  相似文献   
55.

Aim

The aim of this study was to evaluate the use of the London Atlas of Human Tooth Development and Eruption for age estimation in Saudi Arabian children and adolescents (aged 2–20 years), for forensic odontology application.

Materials and methods

This cross-sectional survey analyzed orthopantomograms (OPGs) of the complete dentition (including root development) to estimate the deviation from chronological age. Each OPG was de-identified and analyzed individually and classified into age-groups by the lead author, using the methods of the Atlas of Tooth Development.

Results

OPGs from a total of 252 patients [110 (44%) males, 142 (56%) females] aged 2–20 years (24–240 months) were examined in this study. The average estimated and chronological ages of subjects differed significantly p < 0.001 (143 ± 55.4 vs. 145 ± 57.9 months). Most (65.5%) estimates were within 12 months of subjects’ chronological ages; 19% overestimated and 15.5% underestimated age by >12 months.

Conclusion

This study, conducted in a sub-population of different origin than the UK sample used for the development of the London Atlas, identified variation in age estimates that may have significant impacts on results. The establishment of a composite international repository of atlas-based data for diverse ethnic sub-populations would be of great value to clinicians across the globe.  相似文献   
56.
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58.

Aims  

The aim of this study was to quantify the risk of major congenital anomaly, and to assess the influence of peri-conception HbA1c and other clinical and socio-demographic factors on the risk of congenital anomaly occurrence in offspring of women with type 1 and type 2 diabetes diagnosed before pregnancy.  相似文献   
59.
60.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
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