Conformationally constrained analogues of 2-arachidonoylglycerol

Novel monocyclic analogues of 2-arachidonoylglycerol (2-AG) were designed in order to explore the pharmacophoric conformations of this endocannabinoid ligand at the key cannabinergic proteins. All 2-arachidonoyl esters of 1,2,3-cyclohexanetriol [meso-7 (AM5504), (+/-)-8 (AM5503), and meso-9 (AM5505)] were synthesized by regioselective acylation of 2,3-dihydroxycyclohexanone followed by selective reductions. The optically active isomers (+)-8 (AM4434) and (-)-8 (AM4435) were synthesized from (2S,3S)- and (2R,3R)-2,3-dihydroxycyclohexanone, respectively, via a chemoenzymatic route. These head group constrained and conformationally restricted analogues of 2-AG as well as the 1-keto precursors were evaluated as substrates for the endocannabinoid deactivating hydrolytic enzymes monoacylglycerol lipase (MGL) and fatty acid amide hydrolase (FAAH), and also were tested for their affinities for CB1 and CB2 cannabinoid receptors. The observed biochemical differences between these ligands can help define the conformational requirements for 2-AG activity at each of the above endocannabinoid protein targets.     

Comparative in vivo expression of amastigote up regulated Leishmania genes in three different forms of Leishmaniasis

In Old World Leishmania infections in India, Leishmania donovani is responsible for visceral leishmaniasis (VL) and post kala-azar dermal leishmaniasis (PKDL) while L. tropica is responsible for cutaneous leishmaniasis (CL) in humans. The molecular differences between the two species of Leishmania and within the same species causing distinct pathologies that govern the outcome of infection and pathogenesis in the human host are unknown. Quantitative expression of selected genes was evaluated directly in lesion tissues of VL, PKDL and CL patients. Assessment of in vivo mRNA level highlighted substantial differences in gene expression patterns, providing an indication of the genes involved in pathogenesis in the three different forms of Leishmaniasis.     

Prevalence of Tobacco Use in Urban,Semi Urban and Rural Areas in and around Chennai City,India

Background

Tobacco use leads to many health complications and is a risk factor for the occurrence of cardio vascular diseases, lung and oral cancers, chronic bronchitis etc. Almost 6 million people die from tobacco-related causes every year. This study was conducted to measure the prevalence of tobacco use in three different areas around Chennai city, south India.

Methods

A survey of 7510 individuals aged > = 15 years was undertaken covering Chennai city (urban), Ambattur (semi-urban) and Sriperumbudur (rural) taluk. Details on tobacco use were collected using a questionnaire adapted from both Global Youth Tobacco Survey and Global Adults Tobacco Survey.

Results

The overall prevalence of tobacco use was significantly higher in the rural (23.7%) compared to semi-urban (20.9%) and urban (19.4%) areas (P value <0.001) Tobacco smoking prevalence was 14.3%, 13.9% and 12.4% in rural, semi-urban and urban areas respectively. The corresponding values for smokeless tobacco use were 9.5%, 7.0% and 7.0% respectively. Logistic regression analysis showed that the odds of using tobacco (with smoke or smokeless forms) was significantly higher among males, older individuals, alcoholics, in rural areas and slum localities. Behavioural pattern analysis of current tobacco users led to three groups (1) those who were not reached by family or friends to advice on harmful effects (2) those who were well aware of harmful effects of tobacco and even want to quit and (3) those are exposed to second hand/passive smoking at home and outside.

Conclusions

Tobacco use prevalence was significantly higher in rural areas, slum dwellers, males and older age groups in this region of south India. Women used mainly smokeless tobacco. Tobacco control programmes need to develop strategies to address the different subgroups among tobacco users. Public health facilities need to expand smoking cessation counseling services as well as provide pharmacotherapy where necessary.     

PARTIAL PURIFICATION,CHARACTERIZATION, AND KINETIC STUDIES OF A LOW-MOLECULAR-WEIGHT,ALKALI-TOLERANT CHITINASE ENZYME FROM Bacillus subtilis JN032305, A POTENTIAL BIOCONTROL STRAIN

A new alkalophilic low-molecular-mass chitinase of 14 kD from the potent biocontrol agent Bacillus subtilis JN032305 was partially purified and enzymology of the chitinase was studied. The enzyme showed optimal pH of 9.0 and temperature of 50°C. The enzyme was found stable during the 60-min incubation at 50°C. The chitinase was inhibited by group specific agents like IAA, DAN, TLCK, and SDS and metal ions Mg²⁺, Ca²⁺, Fe²⁺, Mn²⁺, Ba²⁺, and Hg²⁺, whereas Zn²⁺ did not show significant inhibitory effect against the chitinase. PMSF partially inhibited the enzyme. Substrates specificity tests indicated that the enzyme showed 75% of relative activity on glycol chitin, 58% on carboxymethylcellulose (CMC), 33% on chitin flakes, and 166% laminarin compared to that on colloidal chitin. The enzyme also hydrolyzed 4-methylumbelliferyl-N-acetyl-D-glucosaminide, indicating its chitobiase activity. The chitinase of this study has broad specificity, which could hydrolyze not only the glycosidic bond in GlcNAc–GlcNAc but also that of related carbohydrates with glycosidic linkages. The partially purified chitinase not only showed antifungal activity against Rhizoctonia solani and Colletotrichum gloeosporioides, two potent phytopathogens of chilli, but also increased the germination of chilli seeds when infected with the two potent phytopathogenic fungi.     

Biolytic extraction of poly(3-hydroxybutyrate) from Bacillus megaterium Ti3 using the lytic enzyme of Streptomyces albus Tia1

The applicability of Streptomyces sp. cell lytic enzymes for devising a simple and competent biological polyhydroxyalkanoate (PHA) recovery approach from Bacillus megaterium cells was investigated. B. megaterium strain Ti3 produced 50% (w/w) PHA using glucose as carbon source. The intracellular PHA was recovered employing a non-PHA accumulating actinomycetes (Tia1) identified as Streptomyces albus, having potent lytic activity against living and heat inactivated B. megaterium. Interestingly, maximum biomass (2.53?±?0.6?g/L by 24?h) of the lytic actinomycete was obtained in PHA production medium itself thus circumventing the prior actinomycete acclimatization just by co-inoculation with B. megaterium as an inducer. Maximum lytic activity was observed at pH 6.0, 40?°C, 220?mg of biomass and 33.3?mL of concentrated culture filtrate in a 100?mL reaction mixture. Preliminary biochemical investigations confirmed the proteolytic and caseinolytic nature of the lytic enzyme. PHA yield of 0.55?g/g by co-inoculation extraction approach was comparable with the conventional sodium hypochlorite based extraction method. Interestingly, S. albus also demonstrated a broad spectrum lytic potential against varied Gram-negative and Gram-positive PHA producers highlighting the extensive applicability of this biolytic PHA recovery approach. The lytic enzyme retained almost 100% relative activity on storage at ?20?°C upto two months. ¹H Nuclear magnetic resonance analysis of the extracted polymer confirmed it as a homopolymer composed of 3-hydroxybutyrate monomeric units. This is the first report on Streptomyces sp. based biological and eco-friendly, intracellular PHA recovery from Bacillus spp.     

Molecular profiling of sepsis in mice using Fourier Transform Infrared Microspectroscopy

Sepsis is a life threatening condition resulting from a high burden of infection. It is a major health care problem and associated with inflammation, organ dysfunction and significant mortality. However, proper understanding and delineating the changes that occur during this complex condition remains a challenge. A comparative study involving intra‐peritoneal injection of BALB/c mice with Salmonella Typhimurium (infection), lipopolysaccharide (endotoxic shock) or thioglycollate (sterile peritonitis) was performed. The changes in organs and sera were profiled using immunological assays and Fourier Transform Infrared (FTIR) micro‐spectroscopy. There is a rapid rise in inflammatory cytokines accompanied with lowering of temperature, respiratory rate and glucose amounts in mice injected with S. Typhimurium or lipopolysaccharide. FTIR identifies distinct changes in liver and sera: decrease in glycogen and protein/lipid ratio and increase in DNA and cholesteryl esters. These changes were distinct from the pattern observed in mice treated with thioglycollate and the differences in the data obtained between the three models are discussed. The combination of FTIR spectroscopy and other biomarkers will be valuable in monitoring molecular changes during sepsis.

Intra‐peritoneal infection with high dose of Salmonella Typhimurium leads to rapid increase in inflammatory cytokines, e.g. Tnfα (A). FTIR analysis of liver (B) and sera (C) identifies several metabolic changes: glycogen, protein/lipid, cholesteryl esters and DNA.     

Folding of a universal ribozyme: the ribonuclease P RNA

Ribonuclease P is among the first ribozymes discovered, and is the only ubiquitously occurring ribozyme besides the ribosome. The bacterial RNase P RNA is catalytically active without its protein subunit and has been studied for over two decades as a model system for RNA catalysis, structure and folding. This review focuses on the thermodynamic, kinetic and structural frameworks derived from the folding studies of bacterial RNase P RNA.