Deposition of Sol–Gel ZnO:Mg Films and Investigation of Their Structural and Optical Properties

This work presents a facile sol–gel method for the deposition of ZnO and ZnO:Mg films. The films are spin coated on silicon and quartz substrates. The impact of magnesium concentrations (0, 0.5, 1, 2 and 3 wt%) and post-annealing treatments (300–600 °C) on the film’s structural, vibrational and optical properties is investigated. Undoped ZnO films crystallize in the wurtzite phase, with crystallite sizes ranging from 9.1 nm (300 °C) to 29.7 nm (600 °C). Mg doping deteriorates the film crystallization and shifting of 002 peak towards higher diffraction angles is observed, indicating the successful incorporation of Mg into the ZnO matrix. ZnO:Mg films (2 wt%) possess the smallest crystallite size, ranging from 6.2 nm (300 °C) to 25.2 nm (600 °C). The highest Mg concentration (3 wt%) results into a segregation of the MgO phase. Lattice constants, texture coefficients and Zn–O bond lengths are discussed. The diminution of the c lattice parameter is related to the replacement of Zn²⁺ by Mg²⁺ in the ZnO host lattice. The vibrational properties are studied by Fourier transform infrared (FTIR) spectroscopy. IR lines related to Mg–O bonds are found for ZnO:Mg films with dopant concentrations of 2 and 3 wt%. The optical characterization showed that the transmittance of ZnO:Mg thin films increased from 74.5% (undoped ZnO) to about 89.1% and the optical band gap energy from 3.24 to 3.56 eV. Mg doping leads to a higher refractive index compared to undoped ZnO films. The FESEM (field emission scanning electron microscopy) technique is used for observation of the surface morphology modification of ZnO:Mg films. The doped ZnO films possess a smoother grained surface structure, opposite to the wrinkle-type morphology of undoped sol–gel ZnO films. The smoother surface leads to improved transparency of ZnO:Mg films.     

Circulating glutamate level as a potential biomarker for abdominal obesity and metabolic risk

Background and aimCirculating level of glutamate, a by-product of the catabolism of branched-chain amino acids, has been positively correlated with visceral adipose tissue accumulation and waist circumference (WC). The aim of the present study was to assess the potential of using glutamate level to identify individuals with abdominal obesity and a high cardiometabolic risk.Methods and resultsThe study sample included 99 men and 99 women. Fasting serum glutamate was measured using the Biocrates p180 kit. Anthropometric and metabolic variables were used to identify individuals with abdominal obesity (WC ≥ 95 cm in both sexes), the hypertriglyceridemic waist (HTW) phenotype and the metabolic syndrome (MetS). Mean (±SD) age was 34.1 ± 10.1 years, mean BMI was 29.0 ± 6.2 kg/m² and mean WC was 92.7 ± 16.5 cm. Glutamate was strongly correlated with WC (r = 0.66 for men; r = 0.76 for women, both p < 0.0001) and multiple markers of metabolic dysfunction, particularly fasting triglyceride level (r = 0.59 for men; r = 0.57 for women, both p < 0.0001), HDL-cholesterol level (r = ?0.45, p < 0.0001 in both sexes) and the HOMA-IR index (r = 0.65 for men; r = 0.60 for women, both p < 0.0001). Logistic regressions showed that glutamate had an excellent accuracy to identify individuals with abdominal obesity (ROC_AUC: 0.90 for both sexes), a good accuracy to identify those with the HTW phenotype (ROC_AUC: 0.82 for men; 0.85 for women) and fair-to-good accuracy for the MetS (ROC_AUC: 0.78 for men; 0.89 for women).ConclusionGlutamate level may represent an interesting potential biomarker of abdominal obesity and metabolic risk.     

Tissue microarray analysis as a screening tool for neuroendocrine carcinoma of the breast

Neuroendocrine carcinoma of the breast (NCB) is a fairly recent diagnostic entity added by WHO in 2003. Since then, studies have indicated that NCB potentially displays a worse prognosis than invasive ductal carcinoma. However, due to a lack of standard use of immunohistochemical staining for neuroendocrine markers and the fact that NCB may only show slight neuroendocrine morphology that can easily be overlooked, NCB is often underdiagnosed. Consequently, there is a need for fast and reliable detection method for NCB. Here, we take a first step toward finding an easy way of identifying NCB by investigating the usefulness of tissue microarray (TMA) analysis as a screening tool. We present our findings with regard to sensitivity and specificity compared with whole‐mount sections. The material consists of 240 cases of breast cancer divided into 20 TMA blocks that were all immunohistochemically stained for the neuroendocrine markers chromogranin A and synaptophysin. Cases positive in more than 50% of the tumor cells were accepted in accordance with WHO (2003) standards of NCB. Sensitivity and specificity for TMA sections vs whole‐mount sections were found to be 100% and 97.8%, respectively, suggesting that TMA analysis is a reliable method for NCB detection.     

Fine and gross motor skills differ between healthy-weight and obese children

Within the obesity literature, focus is put on the link between weight status and gross motor skills. However, research on fine motor skills in the obese (OB) childhood population is limited. Therefore, the present study focused on possible weight related differences in gross as well as fine motor skill tasks. Thirty-four OB children (12 ♀ and 22 ♂, aged 7–13 years) were recruited prior to participating in a multidisciplinary treatment program at the Zeepreventorium (De Haan, Belgium). Additionally, a control group of 34 age and gender-matched healthy-weight (HW) children was included in the study. Anthropometric measures were recorded and gross and fine motor skills were assessed using the Bruininks–Oseretsky Test of Motor Proficiency, second edition (BOT-2). Results were analyzed by independent samples t-tests, multivariate analysis of variance, and a chi-squared test. Being OB was detrimental for all subtests evaluating gross motor skill performance (i.e., upper-limb coordination, bilateral coordination, balance, running speed and agility, and strength). Furthermore, OB children performed worse in fine motor precision and a manual dexterity task, when compared to their HW peers. No group differences existed for the fine motor integration task. Our study provides evidence that lower motor competence in OB children is not limited to gross motor skills alone; OB children are also affected by fine motor skill problems. Further investigation is warranted to provide possible explanations for these differences. It is tentatively suggested that OB children experience difficulties with the integration and processing of sensory information. Future research is needed to explore whether this assumption is correct and what the underlying mechanism(s) could be.     

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.

     

Epstein‐Barr virus load in the peripheral blood of patients with rheumatoid arthritis: Accurate quantification using real‐time polymerase chain reaction

Objective

To determine whether patients with rheumatoid arthritis (RA) have elevated Epstein‐Barr virus (EBV) load in their peripheral blood mononuclear cells (PBMCs) and whether it is correlated with the HLA–DR genes they express, we developed an accurate EBV DNA quantitative assay using real‐time polymerase chain reaction (PCR) with fluorescent probes.

Methods

We studied the EBV DNA load in the PBMCs of 84 patients with RA, 69 normal controls, and 22 patients with rheumatic conditions other than RA. A 214‐bp segment from the long internal repeat of EBV was amplified from 500 ng of PBMC DNA (150,000 cells) and quantified by real‐time PCR with fluorescent probes.

Results

We demonstrated that in patients with RA, the EBV DNA load in PBMCs is increased almost 10‐fold compared with that in normal controls. The EBV load is stable over time and is not obviously influenced by disease‐modifying antirheumatic drugs or HLA–DR.

Conclusion

Patients with RA have elevated EBV load in their peripheral blood.

     

Delayed leukoencephalopathy from suspected polymer embolism after neuroendovascular procedures

As the neurointervention field grows, a new side effect emerges. Delayed leukoencephalopathy (DL) is believed to be an inflammatory or allergic reaction to polymer material that is shed from catheters during endovascular procedures. We present four cases of DL after aneurysm treatment in two patients, endovascular stroke treatment and diagnostic arteriography. We present our diagnostic process, including biopsy results in two patients, our anti-inflammatory treatment and outcomes together with a review of the literature. In our series, prognosis was variable with ongoing seizures in two patients. Our literature review reveals that asymptomatic shedding of polymer material is common, occurring in a third of endovascular stroke procedures, whereas symptomatic DL occurs in <0.5% of therapeutic neuroendovascular procedures. Clinicians should be aware of this rare complication, and oral glucocorticoids seem to be a reasonable first-line treatment strategy.