The Influence of Melatonin and Light on VEGF Secretion in Primary RPE Cells

(1) Background: Retinal pigment epithelial cells (RPE) cells constitutively secrete vascular endothelial growth factor (VEGF) in the retina, protecting the neuronal cells and the choroid. Increased VEGF secretion, however, can result in neovascularization and edema. Many factors regulate VEGF secretion. In this study, we investigated the effect of external stimuli in relation to diurnal rhythm on constitutive VEGF secretion. (2) Methods: Single-eye RPE cell culture was prepared from porcine eyes. RPE cells were cultured in darkness, treated with daylight or room light, and treated with melatonin at different time frames, either respectively or in combination. Supernatants were collected and VEGF content evaluated using ELISA. Expression of the clock protein BMAL1 was evaluated with Western blot. (3) Results: VEGF secretion of the RPE shows a diurnal rhythm. While the rhythm is not influenced by either light or melatonin, the amount of secreted VEGF can be increased by nocturnal melatonin, especially in combination with morning daylight. These findings disclose another layer of VEGF regulation in the retina

Bulk single crystals and physical properties of β-(AlxGa1-x)2O3(x = 0-0.35) grown by the Czochralski method

We have systematically studied the growth, by the Czochralski method, and basic physical properties of a 2 cm and 2 in. diameter bulk β-(AlxGa1-x)2O3 single crystal with [Al] = 0-35 mol. % in the melt in 5 mol. % steps. The segregation coefficient of Al in the Ga2O3 melt of 1.1-1.2 results in a higher Al content in the crystals than in the melt. The crystals were also co-doped with Si or Mg. [Al] = 30 mol. % in the melt (33-36 mol. % in the crystals) seems to be a limit for obtaining bulk single crystals of high structural quality suitable for homoepitaxy. The crystals were either semiconducting (no intentional co-dopants with [Al] = 0-30 mol. % and Si-doped with [Al] = 15-20 mol. %), degenerately semiconducting (Si-doped with [Al] ≤ 15 mol. %), or semi-insulating ([Al] ≥ 25 mol. % and/or Mg-doped). The full width at half maximum of the rocking curve was 30-50 arcsec. The crystals showed a linear but anisotropic decrease in all lattice constants and a linear increase in the optical bandgap (5.6 eV for [Al] = 30 mol. %). The room temperature electron mobility at similar free electron concentrations gradually decreases with [Al], presumably due to enhanced scattering at phonons as the result of a larger lattice distortion. In Si co-doped crystals, the scattering is enhanced by ionized impurities. Measured electron mobilities and bandgaps enabled to estimate the Baliga figure of merit for electronic devices

Advances in Electronic-Nose Technologies Developed for Biomedical Applications

The research and development of new electronic-nose applications in the biomedical field has accelerated at a phenomenal rate over the past 25 years. Many innovative e-nose technologies have provided solutions and applications to a wide variety of complex biomedical and healthcare problems. The purposes of this review are to present a comprehensive analysis of past and recent biomedical research findings and developments of electronic-nose sensor technologies, and to identify current and future potential e-nose applications that will continue to advance the effectiveness and efficiency of biomedical treatments and healthcare services for many years. An abundance of electronic-nose applications has been developed for a variety of healthcare sectors including diagnostics, immunology, pathology, patient recovery, pharmacology, physical therapy, physiology, preventative medicine, remote healthcare, and wound and graft healing. Specific biomedical e-nose applications range from uses in biochemical testing, blood-compatibility evaluations, disease diagnoses, and drug delivery to monitoring of metabolic levels, organ dysfunctions, and patient conditions through telemedicine. This paper summarizes the major electronic-nose technologies developed for healthcare and biomedical applications since the late 1980s when electronic aroma detection technologies were first recognized to be potentially useful in providing effective solutions to problems in the healthcare industry

Genetics of autoimmune hypoparathyroidism

Primary hypoparathyroidism not only occurs as an isolated idiopathic autoimmune disease (idiopathic hypoparathyroidism) but also as a component disease within the scope of autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). Hypoparathyroidism constitutes the major endocrine component disease in APECED occurring in 80-90% of patients and manifests during childhood. The inheritance of APECED, monogenic and autosomal-recessive, is due to a defect in a single gene, called autoimmune regulator gene (AIRE) which has been identified in 1997 and mapped to chromosome 21. So far, 45 different mutations have been detected throughout the entire coding region of the AIRE gene. Two mutations in exon 6 (R257X) and exon 8 (13-bp deletion), occur most frequently in European and North American populations, respectively. They are responsible for the expression of a truncated autoimmune regulator protein. There is evidence that the AIRE protein has a central role in maintenance of immune tolerance. It has multiple domains which are discussed to be involved in transcriptional activity, nuclear transport, DNA binding, and homomultimerization. Mutational analysis of AIRE gene allows to identify patients at risk for APECED. On the other hand, it can help to distinguish patients with APECED from those with isolated hypoparathyroidism, and thereby, avoiding family members not having APECED of unnecessary follow-up. However, the absence of a mutation in the AIRE gene does not exclude the APECED. Therefore, diagnosis is dependent on the determination of the clinical picture of the syndrom

Functional and Postural Lateral Preferences in Humans: Interrelations and Life-Span Age Differences

This study aimed to provide data on lateral preferences among older subjects, to analyze age differences, and to determine interrelations between lateral preferences. Four functional preferences (handedness, footedness, eyedness, earedness) and three postural lateral preferences (hand-clasping, arm-folding, leg-crossing) were assessed in 628 Germans (252 men, 376 women) aged between19 and 90 years. Sex differences, age differences, and associations between lateralities were analyzed applying chi-square tests. Logistic regression analyses considering age, sex, and interactions between variables were applied to analyze combined effects on laterality measures. Right-sided preference for handedness, footedness, eyedness, earedness, and leg-crossing characterized 86.8%, 77.1%, 70.9%, 67.8%, and 56.6%, respectively, of subjects, while a left-sided preference for hand-clasping and armfolding characterized 56.4% and 60.2%, respectively, of all participants. Results are within the range of other populations. Only footedness differed between the sexes: there were more left-footed men. Older cohorts showed a rightward shift in handedness, eyedness, earedness, and leg-crossing, the opposite for arm-folding. No age-related differences exist in footedness or hand-clasping. Logistic regression models indicate no interaction between age and sex for each laterality measure. The four functional lateralities are significantly interrelated. All also are positively associated with leg-crossing. Conversely, the postural lateralities generally are not correlated, although leg-crossing and arm-folding are, inversely. The observed relationships among lateralities support the hypothesis that handedness, footedness, legcrossing, and earedness might be aspects of a larger phenotype that is independent of hand-clasping and arm-folding

Effect of diurnal variation on body composition under consideration of selected chronobiological marker systems

Diurnal variation in body composition in relation to chronobiological parameters was analyzed in 27 healthy students (22-29 years) four times over one day from 5:35 to 0:15 h. Body composition was determined by multifrequency bioimpedance analysis at fixed frequencies (1, 5, 50, 100 kHz). Resistance (R) and reactance (Xc) were measured. Total, extra and intracellular body water (TBW, ECW, ICW), lean body mass (LBM), and fat mass (FM) were derived, and blood pressure and body temperature were measured. Friedman's ANOVA with post hoc Wilcoxon matched pairs tests revealed a diurnal variability. R and Xc declined in the course of the day. Weight, TBW, ECW, ICW, LBM and ECM increased, whereas height decreased. Chronobiology did not significantly influence FM. Body composition variables displayed inverse associations to RRdiastolic. The diurnal decrease is probably influenced by food and fluid intake. the representative values for body composition should be the morning measures