ZINC AND IMMUNE FUNCTION IN DOWN'S SYNDROME

Abstract. Björkstén, B., Bäck, O., Gustavson, K. H., Hallmans, G., Hägglöf, B. and Tarnvik, A. (Departments of Clinical Bacteriology, Dermatology, Paediatrics and Pathology, University Hospital, Umeä, Sweden). Zinc and immune function in Down's syndrome. Acta Paediatr Scand, 69: 183, 1980.—Low levels of zinc in serum and high in blood clots were found in 12 patients with Down's syndrome (DS). They also had an immune deficiency characterized by depressed neutrophil chemotaxis, skin hypersensitivity and lymphocyte responsiveness to PHA in vitro . The patients received zinc sulphate, corresponding to 135 mg Zn⁺⁺ daily. After treatment for 2 months' serum zinc levels had increased, neutrophil chemotactic responsiveness was normal in 11 of the 12 patients and there were improved lymphocyte responses to high doses of PHA in vitro . Delayed skin reactivity to DNCB was also improved in 10 of 11 patients after zinc therapy. Zinc deficiency may in part explain the increased susceptibility to infection in DS.     

Expansion of a 12-kb VNTR containing the REXO1L1 gene cluster underlies the microscopically visible euchromatic variant of 8q21.2

Copy number variants visible with the light microscope have been described as euchromatic variants (EVs) and EVs with extra G-light material at 8q21.2 have been reported only once before. We report four further patients with EVs of 8q21.2 ascertained for clinical (3) or reproductive reasons (1). Enhanced signal strength from two overlapping bacterial artificial chromosomes (BACs) and microarray analysis mapped the EV to a 284-kb interval in the reference genome. This interval consists of a sequence gap flanked by segmental duplications that contain the 12-kb components of one of the largest Variable Number Tandem Repeat arrays in the human genome. Using digital NanoString technology with a custom probe for the RNA exonuclease 1 homologue (S. cerevisiae)-like 1 (REXO1L1) gene within each 12-kb repeat, significantly enhanced diploid copy numbers of 270 and 265 were found in an EV family and a median diploid copy number of 166 copies in 216 controls. These 8q21.2 EVs are not thought to have clinical consequences as the phenotypes of the probands were inconsistent, those referred for reproductive reasons were otherwise phenotypically normal and the REXO1L1 gene has no known disease association. This EV was found in 4/3078 (1 in 770) consecutive referrals for chromosome analysis and needs to be distinguished from pathogenic imbalances of medial 8q. The REXO1L1 gene product is a marker of hepatitis C virus (HCV) infection and a possible association between REXO1L1 copy number and susceptibility to HCV infection, progression or response to treatment has not yet been excluded.     

Making short-term international medical volunteer placements work: a qualitative study

Background

International medical volunteering has grown in recent decades. It has the potential to benefit and harm the volunteer and host countries; but there is a paucity of literature on the impacts of international medical volunteering and a need to find ways to optimise the benefits of such placements.

Aim

In this study, one example of international medical volunteering was examined involving British GPs on short-term placements in Nepal. The intention was to explore the expectations and experiences of the local health workers, volunteers, and host organisation to try and understand what makes volunteer placements work.

Design

Qualitative study of key informant interviews.

Setting

Stakeholders of a short-term international medical volunteer (IMV) placement programme in Nepal.

Method

Key informant interviews were carried out via face-to-face or telephone/internet interviews with five previous volunteers, three representatives from a non-governmental organisation providing placements, and five local health workers in Nepal who had had contact with the IMVs. Interviews were recorded, transcribed, and analysed using standard thematic framework approaches.

Results

All the stakeholders had their own specific motives for participating in the IMV programme. The relationship between volunteers and the Nepalese health workers was complex and characterised by discrepant and occasionally unrealistic expectations. Managing these different expectations was challenging.

Conclusion

Contextual issues and cultural differences are important considerations in medical volunteer programmes, and this study highlights the importance of robust preparation pre-placement for the volunteer and host to ensure positive outcomes.     

Prevalence of Schistosoma intercalatum and S. haematobium Infection among Primary Schoolchildren in Capital Areas of Democratic Republic Of S?o Tomé and Príncipe,West Africa

Background

A parasitological survey of Schistosoma haematobium and S. intercalatum infection among primary schoolchildren in capital area of Democratic Republic of São Tomé and Príncipe (DRSTP) was undertaken.

Methods

Subjects with positive infection were confirmed by the detection of S. haematobium ova in the urine or S. intercalatum ova in the stool by using centrifugation concentration or merthiolate-iodine-formalin concentration method. Totally, 252 urine and stool samples, respectively, were obtained from apparently healthy schoolchildren, of which 121 from boys (9.8 ± 1.4 yr) and 131 from girls (9.7 ± 1.3 yr).

Results

None of participating schoolchildren were found having S. haematobium ova in the urinary specimen. While, among 4 primary schools studied, only schoolchildren from Saint Marçal were detected with S. intercalatum ova in the fecal specimen, making the overall prevalence of S. intercalatum infection among schoolchildren was 2.4% (6/252) and girls had insignificantly higher prevalence (3.1%, 4/131) than that (1.7%, 2/121) in boys (χ² = 0.5, P = 0.5).

Conclusion

Water control and sanitation as well as snails eliminated by molluscicides are urgently needed to reduce S. intercalatum infection in DRSTP inhabitants.