Five treatment procedures evaluated for the elimination of ascorbate interference in the enzymatic determination of urinary oxalate

We evaluated the efficacies of five treatment procedures for eliminating ascorbate interference in the enzymatic determination of urinary oxalate. Aliquots of urine samples, containing different amounts of added ascorbate and oxalate, were individually subjected to ferric chloride, sodium nitrite, sodium periodate, charcoal, or ascorbate oxidase treatment to eliminate ascorbate interference. Oxalate contents of the urine samples were then determined by a banana oxalate oxidase-horseradish peroxidase-linked assay with 3-methyl-2-benzothiazolinone hydrazone and 3-(dimethylamino)benzoic acid as chromogens. Only those urine samples treated with ascorbate oxidase or charcoal consistently gave recovery of oxalate close to 100%. Treatment with other reagents, though improving the recovery of oxalate, gave inconsistent results. On the basis of these data, we describe procedures for simply and reliably assaying oxalate by using banana oxalate oxidase.     

Vision centre helps reduce blindness and vision impairment. Proof of concept in a four-year longitudinal study in an urban area in India

Purpose:To estimate the prevalence of blindness and severe visual impairment (SVI) by using a door-to-door screening and vision center (VC) examination strategy in an urban area in western Maharashtra (Pune), India and repeat the exercise after 4 years to study its impact.Methods:Four trained community health workers measured the visual acuity and performed an external ocular examination in patients’ homes. People with vision <6/18 were requested to visit the VC for a comprehensive eye examination by an optometrist. An ophthalmologist examined people whose vision did not improve to 6/12. A home examination was done for people who did not visit the VC despite two requests. The same population was examined twice in an interval of 4 years.Results:In the study, 44,535 people in 2015–16 and 98.14% (n = 43,708) of them in 2018–19 were examined. Blindness (vision < 3/60 in better eye), and moderate-to-severe visual impairment (MSVI, vision 6/18–6/60 in better eye) were 0.26% and 1.3%, respectively, in the first cohort, and 0.16% and 1.1%, respectively, in the second cohort (P < 0.001). When the worse eye was considered, the prevalence of blindness reduced from 0.72% to 0.44%, SVI reduced from 0.1% to 0.07%, and MVI decreased from 1.7% to 1.49% between 2015 and 2019 (P < 0.001). Females (P < 0.001) and older individuals (P < 0.001) were more likely to have blindness or SVI. In the VC, 8211 people were examined in 4 years.Conclusion:The reduction of blindness and MSVI in the urban area of Pune can be partly ascribed to the presence of a VC and attendant screening in this locality.     

Volatile organic compounds from fungi isolated after hurricane katrina induce developmental defects and apoptosis in a Drosophila melanogaster model

In previous work, our laboratory developed a Drosophila model for studying the adverse effects of fungal volatile organic compounds (VOCs) emitted by growing cultures of molds. In this report, we have extended these studies and compared the toxic effects of fungal VOCs emitted from living cultures of four molds isolated after Hurricane Katrina from a flooded home in New Orleans. Strains of Aspergillus, Mucor, Penicillium, and Trichoderma were grown with wild‐type larvae and the toxic effects of volatile products on the developmental stages of Drosophila larvae were evaluated. Furthermore, heterozygous mutants of Drosophila carrying the apoptotic genes, reaper and dronc, were used to assess the role of apoptosis in fungal VOCs mediated toxicity. Third‐instar larvae of Drosophila carrying these apoptotic genes were exposed to fungal VOCs emitted from growing mold cultures for 10 days. The larval strains carrying apoptopic genes survived longer than the control wild type larvae; moreover, of those that survived, heterozygous reaper and dronc strains progressed to pupae and adult phases more rapidly, suggesting that fungal VOCs may induce apoptotic changes in flies. These data lend support to the use of Drosophila as an inexpensive and genetically versatile toxicological model to investigate the mechanistic basis for some of the human illnesses/symptoms associated with exposure to mold‐contaminated indoor air, especially after hurricanes. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 614–620, 2015.     

Multivariate analyses of the EEG in normal adolescents

We investigated the computerized electroencephalography (cEEG) in a group of 85 normal adolescents. The spatial frequency of the cEEG was analyzed using various multivariate statistical techniques. The factor analyses revealed three factors that accounted for most of the variability in the data and that could be interpreted as a low versus high frequency, a beta frequency, and a frontal versus posterior factor. The cluster analysis revealed various EEG patterns that distinguished among subgroups of normal individuals.