Patients with a deficiency of natural killer cell activity lack the VEP13-positive lymphocyte subpopulation

Many patients with B-type chronic lymphocytic leukemia (CLL) exhibit a profound defect in their natural killer (NK) cell activity, the basis of which is still obscure. Hence, we analyzed the NK cells from peripheral blood samples from 11 patients with CLL for phenotype and function, after removal of the leukemic cells with a monoclonal antibody (BA-1) plus complement. Phenotypic analysis of these nonleukemic cells with monoclonal antibodies (MoAbs) against NK cells revealed that the CLL patients had higher percentages of HNK-1-positive cells (23.5% compared to controls with 14.7%). In contrast, VEP13- positive cells were absent or low in seven patients (0.8% compared to controls with 11.2%) and normal in four patients (10.5%). When testing NK cell activities against K562 or MOLT 4 target cells, patients with no or minimal numbers of VEP13-positive cells were found to be deficient, while patients with normal percentages of VEP13-positive cells had NK cell activity comparable to controls. Isolation by fluorescence-activated cell sorter of HNK-1-positive cells from patients lacking VEP13-positive cells and NK cell activity indicated that the majority of the HNK-1-positive cells in these patients had the large granular lymphocyte morphology that is characteristic of NK cells. Thus, the deficiency of NK cell activity in CLL patients appears to result from the absence of cells carrying the VEP13 marker.     

Effectiveness of a school-based physical activity-related injury prevention program on risk behavior and neuromotor fitness a cluster randomized controlled trial

Background

To investigate the effects of a school-based physical activity-related injury prevention program, called 'iPlay', on risk behavior and neuromotor fitness.

Methods

In this cluster randomized controlled trial 40 primary schools throughout the Netherlands were randomly assigned in an intervention (n = 20) or control group (n = 20). The study includes 2,210 children aged 10-12 years. The iPlay-intervention takes one school year and consists of a teacher manual, informative newsletters and posters, a website, and simple exercises to be carried out during physical education classes. Outcomes measures were self-reported injury preventing behavior, self-reported behavioral determinants (knowledge, attitude, social-influence, self-efficacy, and intention), and neuromotor fitness.

Results

The iPlay-program was not able to significantly improve injury-preventing behavior. The program did significantly improve knowledge and attitude, two determinants of behavior. The effect of the intervention-program on behavior appeared to be significantly mediated by knowledge and attitude. Improved scores on attitude, social norm, self-efficacy and intention were significantly related to changes in injury preventing behavior. Furthermore, iPlay resulted in small non-significant improvements in neuromotor fitness in favor of the intervention group.

Conclusion

This cluster randomized controlled trial showed that the iPlay-program did significantly improved behavioral determinants. However, this effect on knowledge and attitude was not strong enough to improve injury preventing behavior. Furthermore, the results confirm the hypothetical model that injury preventing behavior is determined by intention, attitude, social norm and self-efficacy.

Trial number

ISRCTN78846684     

Heme oxygenase-1 system and gastrointestinal tumors

Heme oxygenase-1(HO-1) system catabolizes heme into three products:carbon monoxide,biliverdin/bilirubin and free iron.It is involved in many physiological and pathophysiological processes.A great deal of data has demonstrated the roles of HO-1 in the formation,growth and metastasis of tumors.The interest in this system by investigators involved in gastrointestinal tumors is fairly recent,and few papers on HO-1 have touched upon this subject.This review focuses on the current understanding of the physiologic...     

Karyotyping or rapid aneuploidy detection in prenatal diagnosis? The different views of users and providers of prenatal care

Developments in prenatal diagnosis raise the question which test strategy should be implemented. However, preferences of women and caregivers are underexposed. This study investigates what kind of prenatal test pregnant women and caregivers prefer and if differences between the groups exist, using self-report questionnaires. Women preferred either karyotyping (50%) or rapid aneuploidy detection (43%). Caregivers opted for the latter (78%). A test targeted on Down syndrome was the least preferred in both groups. We recommend the use of individualised choice for genetic test in prenatal diagnosis, overcoming the existing differences in preferences between women and caregivers.     

Hydrogen peroxide alters sternohyoid muscle function

Upper airway (UA) dilator muscles are critical for the maintenance of airway patency. Injury or fatigue to this group of muscles, as observed in patients with obstructive sleep apnoea (OSA) and animal models of OSA, may leave the UA susceptible to collapse. Although the mechanisms underlying respiratory muscle dysfunction are not completely understood, there is strong evidence suggesting a link between increased production of reactive oxygen species and altered muscle function. The aim of this study was to examine the effects of H₂O₂ on rat sternohyoid muscle function in vitro. Sternohyoid contractile and endurance properties were examined at 35°C under control or hypoxic conditions. Studies were conducted in the presence of varying concentrations of H₂O₂ (0, 0.01, 0.1 and 1 mM). Muscle function was also examined in the presence of antioxidants [desferoxamine (DFX), catalase] and the reducing agent dithiothreitol (DTT). H₂O₂ decreased muscle endurance in a concentration‐dependent manner. This was partially reversed by catalase, DFX and DTT. Our results suggest that oxidants may contribute to UA respiratory muscle dysfunction with implications for the control of UA patency in vivo.     

Dietary behavior and knowledge of dental erosion among Chinese adults

Objectives  

To study the dietary behavior and knowledge about dental erosion and self-reported symptoms that can be related to dental erosion among Chinese adults in Hong Kong.     

Generation Scotland: Donor DNA Databank; A control DNA resource

Background  

Many medical disorders of public health importance are complex diseases caused by multiple genetic, environmental and lifestyle factors. Recent technological advances have made it possible to analyse the genetic variants that predispose to complex diseases. Reliable detection of these variants requires genome-wide association studies in sufficiently large numbers of cases and controls. This approach is often hampered by difficulties in collecting appropriate control samples. The Generation Scotland: Donor DNA Databank (GS:3D) aims to help solve this problem by providing a resource of control DNA and plasma samples accessible for research.