Genetic kinship among an isolated Adi tribe of Arunachal Pradesh: isonymy in the Adi Panggi

Isolated tribes in remote areas are important for genetic studies, and one such little known subtribe of the Adi tribe, namely, the Adi Panggi (Pangi) of the Upper Siang District of Arunachal Pradesh, India, was studied for surname distribution to deduce the deviation from random mating and genetic kinship between villages. The estimates of homonymy (homozygosity) vary between villages; husbands show wider variation (0.009 to 0.23) than wives (0.005 to 0.054). The remote villages of Sumsing and Sibum and Geku Town show lower entropy among husbands' surnames than among Panggi wives. The highest equivalent surname number was found among Sibum husbands (9.9), Panggi wives (12.6), and Panggi and non-Panggi wives (13.5). The estimates of unbiased random isonymy among husbands and wives together show the smallest values in Sibum (0.05) and the highest values in Sumsing and Ramku (0.16). The random and nonrandom components of the inbreeding coefficient show avoidance of inbreeding among the Panggi villages (-0.012 to -0.27) except in Sibum (0.012). Genetic kinship between villages based on the Mij distance shows different clusters of villages among husbands and wives. Both the Panggi wives and the Panggi and non-Panggi wives show a similar pattern of clustering between villages. The wide homonymy variation between villages among the patrilocal Adi Panggi indicates differential genetic kinetics among husbands and wives, avoidance of inbreeding, and female-oriented differential gene flow with little effect on the overall intervillage genetic kinship.     

HOMO based two electrons and one-electron oxidation in planar and nonplanar methoxy-substituted nickel tetraphenylporphyrins

A series of methoxy-substituted nickel tetra phenylporphyrins were synthesized by a direct method to correlate their electrochemical properties with nonplanar distortion of the porphyrin rings. From the newly synthesized nickel tetraphenylporphyrin complexes with o,p-dimethoxy [T(2,4-OMe)PPNi], o,m-dimethoxy [T(2,5-OMe)PPNi], m,p-dimethoxy [T(3,4-OMe)PPNi], and o,o′, p-trimethoxy [T(2,4,6-OMe)PPNi] substituted phenyl groups, the planar T(2,4,6-OMe)PPNi structure elucidated by X-ray crystallography shows two well separated one-electron oxidations at +0.85 V and +1.22 V. Among previously reported nickel tetraphenylporphyrins with p-methoxy [T(4-OMe)PPNi] and m,m′,p-trimethoxy [T(3,4,5-OMe)PPNi] substituted phenyl groups, the structurally characterized highly distorted T(3,4,5-OMe)PPNi shows a two-electron oxidation occurring at the potential of +1.05 V. Density functional theory (DFT) calculations performed on the nickel porphine systems show lowering of HOMO-LUMO gap in distorted ruffled or saddled systems with change in the energy level of HOMO and HOMO−1. While the decrease in HOMO-LUMO gap can explain the lowering in the difference between first oxidation potential and first reduction potential, Δ|Ox1 − Red1|, the degeneracy or near-degeneracy of HOMO and HOMO−1 in distorted systems explains the two-electron oxidation process due to pseudo-Jahn-Teller distortion in highly distorted nickel porphyrins.     

Functional Genetic Variants of the Catecholamine-Release-Inhibitory Peptide Catestatin in an Indian Population: ALLELE-SPECIFIC EFFECTS ON METABOLIC TRAITS*

Catestatin (CST), a chromogranin A (CHGA)-derived peptide, is a potent inhibitor of catecholamine release from adrenal chromaffin cells and postganglionic sympathetic axons. We re-sequenced the CST region of CHGA in an Indian population (n = 1010) and detected two amino acid substitution variants: G364S and G367V. Synthesized CST variant peptides (viz. CST-Ser-364 and CST-Val-367) were significantly less potent than the wild type peptide (CST-WT) to inhibit nicotine-stimulated catecholamine secretion from PC12 cells. Consistently, the rank-order of blockade of nicotinic acetylcholine receptor (nAChR)-stimulated inward current and intracellular Ca²⁺ rise by these peptides in PC12 cells was: CST-WT > CST-Ser-364 > CST-Val-367. Structural analysis by CD spectroscopy coupled with molecular dynamics simulations revealed the following order of α-helical content: CST-WT > CST-Ser-364 > CST-Val-367; docking of CST peptides onto a major human nAChR subtype and molecular dynamics simulations also predicted the above rank order for their binding affinity with nAChR and the extent of occlusion of the receptor pore, providing a mechanistic basis for differential potencies. The G364S polymorphism was in strong linkage disequilibrium with several common CHGA genetic variations. Interestingly, the Ser-364 allele (detected in ∼15% subjects) was strongly associated with profound reduction (up to ∼2.1-fold) in plasma norepinephrine/epinephrine levels consistent with the diminished nAChR desensitization-blocking effect of CST-Ser-364 as compared with CST-WT. Additionally, the Ser-364 allele showed strong associations with elevated levels of plasma triglyceride and glucose levels. In conclusion, a common CHGA variant in an Indian population influences several biochemical parameters relevant to cardiovascular/metabolic disorders.     

5-Membered NH...N hydrogen bonded molecular scaffold in a model dipeptide containing 3-aminophenylacetic acid: Crystal and solution conformations

Summary Crystallographic and spectroscopic studies of a model dipeptide containing unusual amino acid residues establish the presence of an intramolecular, 5-membered NH…N hydrogen bond involving an amide NH (from 3-amino phenyl acetic acid residue) and an amide N atom from an adjacent amino acid residue in solid state and in solution. The dipeptide also forms an infinite β-sheet ribbon structure in crystals.     

Investigation on Processing Variables for the Preparation of Fluconazole-Loaded Ethyl Cellulose Microspheres by Modified Multiple Emulsion Technique

Fluconazole-loaded ethyl cellulose microspheres were prepared by alginate facilitated (water-in-oil)-in-water emulsion technology and the effects of various processing variables on the properties of microspheres were investigated. Scanning electron microscopy revealed spherical nature and smooth surface morphology of the microspheres except those prepared at higher concentration of emulsifiers and higher stirring speeds. The size of microspheres varied between 228 and 592 μm, and as high as 80% drug entrapment efficiency was obtained depending upon the processing variables. When compared up to 2 h, the drug release in pH 1.2 HCl solution was slower than in pH 7.4 phosphate buffer saline solution. However, this trend was reversed at high shear conditions. The microspheres provided extended drug release in alkaline dissolution medium and the drug release was found to be controlled by Fickian-diffusion mechanism. However, the mechanism shifted to anomalous diffusion at high shear rates and emulsifier concentrations. The aging of microspheres did not influence the drug release kinetics. However, the physical interaction between drug and excipients affected the drug dissolution behaviors. X-ray diffractometry (X-RD) and differential scanning calorimetry (DSC) analysis revealed amorphous nature of drug in the microspheres. Fourier transform infrared (FTIR) spectroscopy indicated stable character of fluconazole in the microspheres. The stability testing data also supported the stable nature of fluconazole in the microspheres. The fluconazole extracted from 80% drug-loaded formulation showed good in vitro antifungal activity against Candida albicans. Thus, proper control of the processing variables involved in this modified multiple emulsion technology could allow effective incorporation of slightly water soluble drugs into ethyl cellulose microspheres without affecting drug stability.     

Genetic heterogeneity among three Adi tribes of Arunachal Pradesh, India

We studied the distribution of ABO blood groups among three little known subtribes of the Adi tribe, namely, the Panggi, Komkar, and Padam, of the East and Upper Siang districts of Arunachal Pradesh, India. Blood group O was the predominant group in the Komkar and Padam, whereas group A was the predominant group in the Panggi. Blood group AB was found to be the least frequent group in all three studied populations. The populations showed significant differences in blood groups A (43% in Panggi, 23% in Komkar, and 18% in Padam) and O (33% in Panggi, 54% in Komkar, and 61% in Padam). The chi-square test indicated significant deviation from Hardy-Weinberg equilibrium, suggesting high heterogeneity among the tribes.     

Potency, efficacy and durability of DNA/DNA, DNA/protein and protein/protein based vaccination using gp63 against Leishmania donovani in BALB/c mice

Background

Visceral leishmaniasis (VL) caused by an intracellular protozoan parasite Leishmania, is fatal in the absence of treatment. At present there are no effective vaccines against any form of leishmaniasis. Here, we evaluate the potency, efficacy and durability of DNA/DNA, DNA-prime/Protein-boost, and Protein/Protein based vaccination against VL in a susceptible murine model.

Methods and Findings

To compare the potency, efficacy, and durability of DNA, protein and heterologous prime-boost (HPB) vaccination against Leishmania donovani, major surface glycoprotein gp63 was cloned into mammalian expression vector pcDNA3.1 for DNA based vaccines. We demonstrated that gp63 DNA based vaccination induced immune responses and conferred protection against challenge infection. However, vaccination with HPB approach showed comparatively enhanced cellular and humoral responses than other regimens and elicited early mixed Th1/Th2 responses before infection. Moreover, challenge with parasites induced polarized Th1 responses with enhanced IFN-γ, IL-12, nitric oxide, IgG2a/IgG1 ratio and reduced IL-4 and IL-10 responses compared to other vaccination strategies. Although, vaccination with gp63 DNA either alone or mixed with CpG- ODN or heterologously prime-boosting with CpG- ODN showed comparable levels of protection at short-term protection study, DNA-prime/Protein-boost in presence of CpG significantly reduced hepatic and splenic parasite load by 10⁷ fold and 10¹⁰ fold respectively, in long-term study. The extent of protection, obtained in this study has till now not been achieved in long-term protection through HPB approach in susceptible BALB/c model against VL. Interestingly, the HPB regimen also showed marked reduction in the footpad swelling of BALB/c mice against Leishmania major infection.

Conclusion/Significance

HPB approach based on gp63 in association with CpG, resulted in robust cellular and humoral responses correlating with durable protection against L. donovani challenge till twelve weeks post-vaccination. These results emphasize the potential of DNA-prime/Protein-boost vaccination over DNA/DNA and Protein/Protein based vaccination in maintaining long-term immunity against intracellular pathogen like Leishmania.     

Changes in Bacterial Community Structure and Abundance in Agricultural Soils under Varying Levels of Arsenic Contamination

Arsenic contamination from groundwater used to irrigate crops is a major issue across several agriculturally important areas of Asia. Assessing bacterial community composition in highly contaminated sites could lead to the identification of novel bioremediation strategies. In this study, the bacterial community structure and abundance are assessed in agricultural soils with varying levels of arsenic contamination at Ambagarh Chauki block, Chhattisgarh, India, based on polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of the 16S rRNA gene and the most probable number-polymerase chain reaction (MPN-PCR). The results revealed that the bacterial communities of arsenic-contaminated soils are dominated by β-proteobacteria (36%), γ-proteobacteria (21%), δ-proteobacteria (11%), α-proteobacteria (11%), and Bacteroidetes (11%). The bacterial composition of high arsenic-contaminated soils differed significantly from that of low arsenic-contaminated soils. The Proteobacteria appeared to be more resistant to arsenic contamination, while the Bacteroidetes and Nitrospirae were more sensitive to it. The bacterial abundance determined by MPN-PCR decreased significantly as As-toxicity increased. In addition to As, other trace metals, like Pb, U, Cu, Ni, Sn, Zn and Zr, significantly ( p < 0.01) explain the changes in bacterial structural diversity in agricultural soils with different level of arsenic contamination, as determined by canonical correspondence analysis (CCA).