Polar and Non-Polar Zn1−xMgxO:Sb Grown by MBE

The article presents a systematic study of Sb-doped Zn_1−xMg_xO layers, with various concentrations of Mg, that were successfully grown by plasma-assisted MBE on polar a- and c-oriented and non-polar r-oriented sapphire substrates. X-ray diffraction confirmed the polar c-orientation of alloys grown on c-and a-oriented sapphire and non-polar structures grown on r-oriented substrates. A uniform depth distribution of the Sb dopant at level of 2 × 10²⁰ cm⁻³ was determined by SIMS measurements. Raman spectroscopy revealed the presence of Sb-related modes in all samples. It also showed that Mg alloying reduces the compressive strain associated with Sb doping in ZnO. XPS analysis indicates that the chemical state of Sb atoms in ZnMgO is 3+, suggesting a substitutional position of Sb_Zn, probably associated with two V_Zn vacancies. Luminescence and transmission spectra were measured to determine the band gaps of the Zn_1−xMg_xO layers. The band gap energies extracted from the transmittance measurements differ slightly for the a, c, and r substrate orientations, and the differences increase with increasing Mg content, despite identical growth conditions. The differences between the energy gaps, determined from transmission and PL peaks, are closely correlated with the Stokes shift and increase with the Mg content in the analyzed series of ZnMgO layers.     

Effects of the Malnutrition—Eat Additional Meal (MEAM) Diet on the Serum Levels of Albumin and C-Reactive Protein in Hemodialysis Patients

The main objective of this project was to evaluate the efficiency of two kinds of nutritional intervention implemented in hemodialysis patients for 24 weeks (traditional nutritional intervention without a meal served before dialysis for group HG1, and nutritional intervention involving a meal served before dialysis for group HG2), and their impact on nutritional status and serum concentrations of C-reactive protein (CRP). Nutritional status and serum biochemical parameters were analyzed in the control group (CG, n = 70) and in two homogeneous groups of patients, HG1 (n = 35) and HG2 (n = 35). There was an interesting trend in both groups of patients connected with increased intake, mainly of energy and protein. In HG1, the greatest increase in energy intake was observed on Sundays, and in HG2 on the days with dialysis. In HG2, after 24 weeks of the nutritional intervention, an increase in serum albumin (p = 0.0157) and a decrease in CRP concentration (p = 0.0306) were observed, whereas in HG1 there was a decrease in serum albumin concentration (p = 0.0043) with no significant change in CRP concentration. The nutritional intervention applied, called the Malnutrition—Eat Additional Meal (MEAM) diet with an easily digestible meal served before dialysis, was aimed at improving the patients’ nutritional status and the obtained results indicate the need not only for substantial reeducation of hemodialysis patients in the area of their diet, but also for undertaking further research and discussions on the possibility of ensuring adequate meals for hemodialysis patients before the dialysis procedure.     

A gene in the telomeric HLA complex distinct from HLA–A is involved in predisposition to juvenile idiopathic arthritis

Objective

Juvenile idiopathic arthritis (JIA) is associated with particular alleles at 3 different HLA loci: HLA–A, HLA–DR/DQ, and HLA–DP. These associations are independent of each other (i.e., they cannot be explained by the known linkage disequilibrium between alleles at these loci). The purpose of this study was to look for additional JIA susceptibility genes in the HLA complex.

Methods

One hundred two Norwegian JIA patients and 270 healthy individuals, all carrying the DQ4;DR8 haplotype, were investigated by scanning ∼10 megabases of DNA covering the HLA complex with microsatellite polymorphisms. An expectation‐maximization algorithm was used to estimate haplotype frequencies, and the distribution of microsatellite alleles on the high‐risk DQ4;DR8 haplotype was compared between patients and controls, to exclude effects secondary to linkage disequilibrium with these susceptibility genes.

Results

Allele 5 at the microsatellite locus D6S265 (D6S265* 5), 100 kb centromeric of HLA–A, showed a strong positive association with the disease (odds ratio 4.7, corrected P < 10⁻⁶). Haplotype analysis demonstrated that the D6S265*5 association was not caused by linkage disequilibrium to the gene encoding HLA–A*02, which has previously been reported to be associated with JIA. Instead, our data suggested that a gene in linkage disequilibrium with D6S265*5, but distinct from HLA–A*02, is involved in the predisposition to JIA.

Conclusion

We found that D6S265*5 could be a marker for an additional susceptibility gene in JIA which is distinct from A*02, adding to the risk conferred by DQ4;DR8.

     

Whole-body MRI for cancer surveillance in ataxia–telangiectasia: A qualitative study of the perspectives of people affected by A-T and their families

Background/Objectives

Ataxia–telangiectasia (A-T) is a complex inherited disease associated with an increased risk of malignancy. Surveillance guidelines have demonstrated significant health benefits in other cancer predisposition syndromes. However, evidence-based guidelines for cancer screening are not currently used in the United Kingdom for people affected by A-T. This study aims to understand how people with A-T and their parents feel about cancer surveillance using whole-body magnetic resonance imaging (MRI) to inform the future development of cancer surveillance guidelines.

Design/Methods

We conducted semistructured interviews with people affected by A-T. Data were analysed inductively using thematic analysis.

Results

Nine parents of children with A-T and four adults with A-T were interviewed. Five main themes emerged from the data, including (1) cancer screening was considered invaluable with the perceived value of early detection highlighted; (2) the cancer fear can increase anxiety; (3) the perceived limitations around current practice, with the responsibility for monitoring falling too strongly on parents and patients; (4) the need for effective preparation for cancer screening, including clear communication and (5) the challenges associated with MRI screening, where specific recommendations were made for improving the child's experience.

Conclusion

This study suggests that stakeholders are positive about the perceived advantages of a cancer screening programme. Ongoing support and preparation techniques should be adopted to maximise adherence and minimise adverse psychosocial outcomes.

Patient or Public Contribution

People with A-T and parents of people with A-T were actively involved in this study by giving their consent to be interviewed. An independent parent representative contributed to the study, supporting the research team in interpreting and commenting on the appropriateness of the language used in this report.     

A genetic association between juvenile rheumatoid arthritis and a novel interleukin-1α polymorphism

Objective. The genetic factors that predispose to the development of juvenile rheumatoid arthritis (JRA) and its complications are not completely understood. The cytokine interleukin-1 (IL-1) has been implicated in the pathogenesis of JRA and other inflammatory diseases. This study was performed to test whether polymorphisms of the IL-1α gene might be associated with JRA. Methods. We sequenced the 5' regulatory region (containing the promoter) of the human IL-1α gene in 18 normal subjects. This revealed a C (IL-1A1) to T (IL-1A2) transition polymorphism at position -889. We studied the frequencies of both alleles in patients with JRA (n = 269) and controls (n = 99). Results. An increased gene carriage of IL-1A2 was found in patients with early-onset, pauciarticular JRA (EOPA-JRA; n = 103) compared with controls (0.66 versus 0.49; P = 0.01, odds ratio [OR] = 2.1). Within this subset of JRA, the association with IL-1A2 was particularly strong in the patients in whom chronic iridocyclitis developed (n = 28) compared with those without chronic iridocyclitis (0.89 versus 0.57; P = 0.002, OR = 6.2). Within the group of EOPA-JRA patients, IL-1A2 was also associated with elevation of the erythrocyte sedimentation rate (P < 0.0025). Conclusion. This is the first report of a cytokine gene association with JRA, and we conclude that IL-1α itself, or a gene for which the IL-1α polymorphism is a marker, may contribute to the pathogenesis of EOPA-JRA and the ocular complications found in this group.     

Hla class ii alleles and heterogeneity of juvenile rheumatoid arthritis. drb1*0101 may define a novel subset of the disease

Objective. To examine the distribution of HLA class II alleles in clinically distinct juvenile rheumatoid arthritis (JRA) subsets. Methods. We typed 298 patients and 181 controls for HLA–DRB1, DQA1, DQB1, and DPB1 alleles using polymerase chain reaction and oligonucleotide probe techniques. Results. Each JRA subset was characterized by a distinct distribution of HLA class II alleles. For the persistently pauciarticular and rheumatoid factornegative polyarticular JRA subsets, certain combinations of DRB1 and DPB1 alleles were characteristic. In patients without antinuclear antibodies and chronic iridocyclitis, there was an increase of DRB1*0101/02 and DQA1*0101. Conclusion. Findings of HLA typing support clinical subdivisions of the disease and suggest the existence of a novel DRB1*0101/02 and DQA1*0101 associated disease subset.