Genetic loci associated with skin pigmentation in African Americans and their effects on vitamin D deficiency

A recent genome-wide association study (GWAS) in African descent populations identified novel loci associated with skin pigmentation. However, how genomic variations affect skin pigmentation and how these skin pigmentation gene variants affect serum 25(OH) vitamin D variation has not been explored in African Americans (AAs). In order to further understand genetic factors that affect human skin pigmentation and serum 25(OH)D variation, we performed a GWAS for skin pigmentation with 395 AAs and a replication study with 681 AAs. Then, we tested if the identified variants are associated with serum 25(OH) D concentrations in a subset of AAs (n = 591). Skin pigmentation, Melanin Index (M-Index), was measured using a narrow-band reflectometer. Multiple regression analysis was performed to identify variants associated with M-Index and to assess their role in serum 25(OH)D variation adjusting for population stratification and relevant confounding variables. A variant near the SLC24A5 gene (rs2675345) showed the strongest signal of association with M-Index (P = 4.0 x 10⁻³⁰ in the pooled dataset). Variants in SLC24A5, SLC45A2 and OCA2 together account for a large proportion of skin pigmentation variance (11%). The effects of these variants on M-Index was modified by sex (P for interaction = 0.009). However, West African Ancestry (WAA) also accounts for a large proportion of M-Index variance (23%). M-Index also varies among AAs with high WAA and high Genetic Score calculated from top variants associated with M-Index, suggesting that other unknown genomic factors related to WAA are likely contributing to skin pigmentation variation. M-Index was not associated with serum 25(OH)D concentrations, but the Genetic Score was significantly associated with vitamin D deficiency (serum 25(OH)D levels less than 12 ng/mL) (OR, 1.30; 95% CI, 1.04–1.64). The findings support the hypothesis suggesting that skin pigmentation evolved responding to increased demand for subcutaneous vitamin D synthesis in high latitude environments.     

Effect of 24-epibrassinolide on growth, protein content and antioxidative defense system of Brassica juncea L. subjected to cobalt ion toxicity

Brassica juncea L. plants were subjected to cobalt (Co) ion (0, 5?×?10^?4, 10^?3, 1.5?×?10^?3 and 2?×?10^?3?M) toxicity and were sprayed with different concentrations of 24-epibrassinolide (24-EBL) (0, 10^?10, 10^?8 and 10^?6?M) at 15-day stage after sowing. They were sampled at 30 and 60?days after sowing and analyzed for growth parameters in terms of shoot length and number of leaves. Thereafter, leaves were excised and content of proteins and the activities of antioxidative enzymes (superoxide dismutase (SOD) (EC 1.15.1.1) catalase (CAT) (EC 1.11.1.6), ascorbate peroxidase (APOX) (EC 1.11.1.11), guaiacol peroxidase (POD) (EC 1.11.1.7) glutathione reductase (GR) (EC 1.6.4.2), monodehydroascorbate reductase (MDHAR) (EC 1.1.5.4) and dehydroascorbate reductase (DHAR) (EC 1.8.5.1)) were analyzed. The plants exposed to cobalt ion exhibited a significant decline in growth in terms of shoot length and number of leaves. However, foliar spray treatment with 24-EBL was able to alleviate the stress generated by cobalt ion and significantly improved the above parameters. The activities of antioxidative enzymes (SOD, CAT, POD, GR, APOX, MDHAR and DHAR) and protein content were also regulated considerably in leaves of plants treated with 24-EBL alone, 10^?8?M concentration being the most effective. The activities of antioxidative enzymes also increased in leaves of B. juncea plants by the application of cobalt ion to soil and consequently sprayed with 24-EBL. Similarly, the protein content was also regulated in leaves of B. juncea plants treated with 24-EBL as compared to untreated control plants, thereby revealing stress-protective properties of 24-EBL.     

Biopotency and identification of allergenic proteins in Periplaneta americana extract for clinical applications.

Commercial cockroach extracts for diagnosis and therapy show batch-to-batch variation. This study aimed to standardize Periplaneta americana extract based on major IgE binding components using hypersensitive patients' sera. Extracts were prepared in phosphate buffered saline (PBS) or NH(4)HCO(3), from freeze-dried or 37 degrees C dried material and compared with commercial extracts by immunobiochemical methods. Cockroach positive patients' sera were collected after intradermal tests and specific IgE enzyme linked immunosorbent assay (ELISA). Allergenic proteins were identified by western-blotting and potency of extracts determined by ELISA-inhibition. Adult P. americana extract from freeze dried source material in PBS (PA extract) resolved into 45 protein bands and showed 22 IgE binding components with pooled patients' sera. It required 9-12 ng self-proteins for 50% ELISA-inhibition. Individual patients' sera identified 23, 28, 35, 38, 40, 49, 72, 78 and 97 kDa as major IgE binding components in PA extract. Nymph extract exhibited similar potency and protein profile to PA extract with 72 and 78 kDa proteins present in high intensities. Commercial extracts exhibited only 6-11 IgE reactive bands compared to PA extract and required 40 folds or more protein for 50% ELISA-inhibition. PA extract from freeze-dried source material seems a potent allergen preparation with 9-major IgE binding components. It can be referred to upgrade the quality of commercial extracts exhibiting low potencies due to poor quality source material, inadequate extraction procedures and improper storage.     

Molecular mapping and transfer of a novel brown planthopper resistance gene bph42 from Oryza rufipogon (Griff.) To cultivated rice (Oryza sativa L.)

Molecular Biology Reports - Brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most destructive pests of rice accounting for 52% of annual yield loss. The breakdown of...     

Surfactant pollution,an emerging threat to ecosystem: Approaches for effective bacterial degradation

The use of surfactants in households and industries is inevitable and so is their discharge into the environment, especially into the water bodies as effluents. Being surface-active agents, their utilization is mostly seen in soaps, detergents, personal care products, emulsifiers, wetting agents, etc. Anionic surfactants are the most used class. These surfactants are responsible for the foam and froth in the water bodies and cause potential adverse effects to both biotic and abiotic components of the ecosystem. Surfactants are capable of penetrating the cell membrane and thus cause toxicity to living organisms. Accumulation of these compounds has been known to cause significant gill damage and loss of sight in fish. Alteration of physiological and biochemical parameters of water decreases the amount of dissolved oxygen and thus affecting the entire ecosystem. Microbes utilizing surfactants as substrates for energy form the basis of the biodegradation of these compounds. The main organisms for surfactant biodegradation, both in sewage and natural waters, are bacteria. Several Pseudomonas and Bacillus spp. have shown efficient degradation of anionic surfactants namely: sodium dodecyl sulphate (SDS), linear alkylbenzene sulphonate (LAS), sodium dodecylbenzenesulphonate (SDBS). Also, several microbial consortia constituting Alcaligenes spp., Citrobacter spp., etc. have shown efficacy in the degradation of surfactants. The biodegradation efficiency studies of these microbes/microbial consortia would be of immense help in formulating better solutions for the bioremediation of surfactants and help to reduce their potential environmental hazards.     

Habitat Adaptation Mediates the Influence of Leaf Traits on Canopy Productivity: Evidence from a Tropical Freshwater Swamp Forest

Ecosystems - Functional traits offer generalizability to the prediction of ecosystem processes such as production, and community-weighted mean trait values are increasingly used for such...     

Universal and cross-cancer prognostic biomarkers for predicting survival risk of cancer patients from expression profile of apoptotic pathway genes

Numerous cancer-specific prognostic models have been developed in the past, wherein one model is applicable for only one type of cancer. In this study, an attempt has been made to identify universal or multi-cancer prognostic biomarkers and develop models for predicting survival risk across different types of cancer patients. In order to accomplish this, we gauged the prognostic role of mRNA expression of 165 apoptosis-related genes across 33 cancers in the context of patient survival. Firstly, we identified specific prognostic biomarker genes for 30 cancers. The cancer-specific prognostic models achieved a minimum Hazard Ratio, HR_SKCM = 1.99 and maximum HR_THCA = 41.59. Secondly, a comprehensive analysis was performed to identify universal biomarkers across many cancers. Our best prognostic model consisted of 11 genes (TOP2A, ISG20, CD44, LEF1, CASP2, PSEN1, PTK2, SATB1, SLC20A1, EREG, and CD2) and stratified risk groups across 27 cancers (HR_OV = 1.53-HR_UVM = 11.74). The model was validated on eight independent cancer cohorts and exhibited a comparable performance. Further, we clustered cancer-types on the basis of shared survival related apoptosis genes. This approach proved helpful in development of cross-cancer prognostic models. To show its efficacy, a prognostic model consisting of 15 genes was thereby developed for LGG-KIRC pair (HR_KIRC = 3.27, HR_LGG = 4.23). Additionally, we predicted potential therapeutic candidates for LGG-KIRC high risk patients.     

<Emphasis Type="Italic">luxRI</Emphasis> homologs are universally present in the genus <Emphasis Type="Italic">Aeromonas</Emphasis>

Background  

Aeromonas spp. have been regarded as "emerging pathogens". Aeromonads possess multifactorial virulence and the production of many of these virulence determinants is associated with high cell density, a phenomenon that might be regulated by quorum sensing. However, only two species of the genus are reported to possess the luxRI quorum sensing gene homologs. The purpose of this study was to investigate if the luxRI homologs are universally present in the Aeromonas strains collected from various culture collections, clinical laboratories and field studies.