Computational Study of ADD1 Gene Polymorphism Associated with Hypertension

We have determined the non-synonymous single-nucleotide polymorphisms (nsSNPs) of ?? adducin 1 (ADD1) gene and its variations in different populations to understand its role in hypertension. Out of 1,113 SNPs, 9 are found to be non-synonymous, of which 7 showed significant damaging effect and one of them showed SNP variability with large differences among the minor allele frequency observed in various populations. The amino acid change found for rs4961 is from glycine to tryptophan, i.e., from an alkyl amino acid to an aromatic amino acid. This residual change is observed in the coiled region of the protein and is also predicted to be disordered by computational algorithm. Protein disorder plays an important role in structural and functional genomics. Hence, because of the complete change in side chains of the amino acid residues occurring in the coiled and disordered region of the protein, the structure of the protein might be altered and the function might be affected, leading to the risk for hypertension.     

Decitabine augments cytotoxicity of cisplatin and doxorubicin to bladder cancer cells by activating hippo pathway through RASSF1A

During the past decade, microRNAs have continuously been suggested as a promising therapeutic tool due to their beneficial effects, such as their multi-targets and multi-functions in pathologic conditions. As a pathologic phenotype is generally regulated by multiple signaling pathways, in this study we identified a microRNA regulating multiple target genes within cardiac hypertrophic signaling pathways. microRNA-133a is known to play a crucial role in cardiac hypertrophy. However, the role of microRNA-133a, which may regulate several signaling pathways in norepinephrine-induced cardiac hypertrophy via multi-targeting, has not been investigated. In the current study, we showed that microRNA-133a can protect cardiomyocyte hypertrophy against norepinephrine stimulation in neonatal rat ventricular cardiomyocytes via new targets, PKCδ and Gq, all of which are related to downstream signaling pathways of the α₁-adrenergic receptor. Taken together, these results suggest the advantages of the therapeutic use of microRNAs as an effective potential drug regulating multiple signaling pathways under pathologic conditions.     

Dengue virus 2 capsid protein chaperones the strand displacement of 5′-3′ cyclization sequences

By virtue of its chaperone activity, the capsid protein of dengue virus strain 2 (DENV2C) promotes nucleic acid structural rearrangements. However, the role of DENV2C during the interaction of RNA elements involved in stabilizing the 5′-3′ panhandle structure of DENV RNA is still unclear. Therefore, we determined how DENV2C affects structural functionality of the capsid-coding region hairpin element (cHP) during annealing and strand displacement of the 9-nt cyclization sequence (5CS) and its complementary 3CS. cHP has two distinct functions: a role in translation start codon selection and a role in RNA synthesis. Our results showed that cHP impedes annealing between 5CS and 3CS. Although DENV2C does not modulate structural functionality of cHP, it accelerates annealing and specifically promotes strand displacement of 3CS during 5′-3′ panhandle formation. Furthermore, DENV2C exerts its chaperone activity by favouring one of the active conformations of cHP. Based on our results, we propose mechanisms for annealing and strand displacement involving cHP. Thus, our results provide mechanistic insights into how DENV2C regulates RNA synthesis by modulating essential RNA elements in the capsid-coding region, that in turn allow for DENV replication.     

Structure-Activity Relationship and Mode of Action of a Frog Secreted Antibacterial Peptide B1CTcu5 Using Synthetically and Modularly Modified or Deleted (SMMD) Peptides

All life forms are equipped with rapidly acting, evolutionally conserved components of an innate immune defense system that consists of a group of unique and diverse molecules known as host defense peptides (HDPs). A Systematic and Modular Modification and Deletion (SMMD) approach was followed to analyse the structural requirement of B1CTcu5, a brevinin antibacterial peptide amide identified from the skin secretion of frog Clinotarsus curtipes, India, to show antibacterial activity and to explore the active core region. Seventeen SMMD-B1CTcu5 analogs were designed and synthesised by C and N-terminal amino acid substitution or deletion. Enhancement in cationicity by N-terminal Lys/Arg substitution or hydrophobicity by Trp substitution produced no drastic change in bactericidal nature against selected bacterial strains except S. aureus. But the sequential removal of N-terminal amino acids had a negative effect on bactericidal potency. Analog B1CTcu5-LIAG obtained by the removal of four N-terminal amino acids displayed bactericidal effect comparable to, or in excess of, the parent peptide with reduced hemolytic character. Its higher activity was well correlated with the improved inner membrane permeabilisation capacity. This region may act as the active core of B1CTcu5. Presence of C-terminal disulphide bond was not a necessary condition to display antibacterial activity but helped to promote hemolytic nature. Removal of the C-terminal rana box region drastically reduced antibacterial and hemolytic activity of the peptide, showing that this region is important for membrane targeting. The bactericidal potency of the D-peptide (DB1CTcu5) helped to rule out the stereospecific interaction with the bacterial membrane. Our data suggests that both the C and N-terminal regions are necessary for bactericidal activity, even though the active core region is located near the N-terminal of B1CTcu5. A judicious modification at the N-terminal region may produce a short SMMD analog with enhanced bactericidal activity and low toxicity against eukaryotic cells.     

Mutations in both gp120 and gp41 Are Responsible for the Broad Neutralization Resistance of Variant Human Immunodeficiency Virus Type 1 MN to Antibodies Directed at V3 and Non-V3 Epitopes

The escape of human immunodeficiency virus type 1 from effects of neutralizing antibodies was studied by using neutralization-resistant (NR) variants generated by growing the neutralization-sensitive (NS) wild-type MN virus in the presence of human serum with neutralizing antibodies, more than 99% of which were directed at the V3 region of gp120. The variants obtained had broad neutralization resistance to human sera, without limitation with respect to the V3 specificity of the sera. The molecular basis for the resistance was evaluated with molecularly cloned viruses, as well as with pseudoviruses expressing envelope glycoproteins of the NS and NR phenotypes. Nucleotide sequence analyses comparing NS and NR clones revealed a number of polymorphisms, including six in the V1/V2 region, two in C4/V5 of gp120, three in the leucine zipper (LZ) domain of gp41, and two in the second external putative α-helix region of gp41. A series of chimeras from NS and NR env genes was constructed, and each was presented on pseudoviruses to locate the domain(s) which conferred the phenotypic changes. The neutralization phenotypes of the chimeric clones were found to be dependent on mutations in both the C4/V5 region of gp120 and the LZ region of gp41. Additionally, interaction between mutations in gp120 and gp41 was demonstrated in that a chimeric env gene consisting of a gp120 coding sequence from an NS clone and a gp41 sequence from an NR clone yielded a pseudovirus with minimal infectivity. The possible significance of predicted amino acid changes in these domains is discussed. The results indicate that polyvalent antibodies predominantly directed against V3 can induce NR through selection for mutations that alter interactions of other domains in the envelope complex.     

Microbial production of 1,3-propanediol: Recent developments and emerging opportunities

1,3-Propanediol, a valuable bifunctional molecule, can be produced from renewable resources using microorganisms. It has several promising properties for many synthetic reactions, particularly for polymer and cosmetic industries. By virtue of being a natural product, relevant biochemical pathways can be harnessed into fermentation processes to produce 1,3-propanediol. Various strategies for the microbial production of 1,3-propanediol are reviewed and compared in this article with their promises and constraints. Furthermore, genetic and metabolic engineering could significantly improve product yields and overcome the limitations of fermentation technology. Present review gives an overview on 1,3-propanediol production by wild and recombinant strains. It also attempts to encompass the various issues concerned in utilization of crude glycerol for 1,3-propanediol production, with particular emphasis laid on biodiesel industries. This review also summarizes the present state of strategies studied for the downstream processing and purification of biologically produced 1,3-propanediol. The future prospect of 1,3-propanediol and its potential as a major bulk chemical are discussed under the light of the current research.     

Curcumin treatment modulates collagen metabolism in isoprot3erenol induced myoxardial necrosis in rats

This study was carried out to evaluate whether curcumin, a potent antioxidant, had any specific role in the synthesis and degradation of collagen in rat heart with mocardial necrosis, induced by isoproterenol.HCI (ISO). Myocardial necrosis was induced by administration of ISO (30 mg/100 g body weight subcutaneously twice at an interval of 24 h) and studies on collagen metabolism were carried out with curcumin (200 mg/kg) pre-and co-treatment with ISO. The incorporation of ₁₄C-proline into collagen was studied as an index of collagen synthesis. The heart weight /body weight ratio,heart RNA/DNA ratio and protein were found to increase significantly in ISO administered animals. Curcumin pre- and co-treatment with ISO reversed these changes and attenuated the development of cardiac hypertrophy two weeks after the second dose of ISO. Increased fractional synthesis rate and enhanced degradation of newly synthesized collagen were observed in ISO administered animals. Curcumin pre- and co-treatment with ISO was noticed to decrease the degree of degradation of the existing collagen matrix and collagen synthesis, two weeks after the second dose of ISO. The observed effects could be due to free radical scavenging capacity and inhibition of lysosomal enzyme release by curcumin.     

LED-Fluorescence Microscopy for Diagnosis of Pulmonary Tuberculosis under Programmatic Conditions in India

Background

Light-emitting diode fluorescence microscopy (LED-FM) has been shown to be more sensitive than conventional bright field microscopy using Ziehl-Neelsen (ZN) stain in detecting sputum smear positive tuberculosis in controlled laboratory conditions. In 2012, Auramine O staining based LED-FM replaced conventional ZN microscopy in 200 designated microscopy centres (DMC) of medical colleges operating in collaboration with India’s Revised National Tuberculosis Control Programme. We aimed to assess the impact of introduction of LED-FM services on sputum smear positive case detection under program conditions.

Methods

This was a before and after comparison study. In 15 randomly selected medical college DMCs, all presumptive TB patients who underwent sputum smear examination in the years 2011 (before LED-FM) and 2012 (after LED-FM) were compared. An additional 15 comparable DMCs that implemented conventional ZN sputum smear microscopy were also selected for comparison between 2011 and 2012.

Results

The proportion of presumptive TB patients (PTP)found sputum smear positive increased by 30%- from 13.6% (3432/25159) in 2011 to 17.8% (4706/26426) in 2012 (P value <0.01) in the sites that implemented LED-FM microscopy, whereas in DMCs where the ZN staining procedure is followed the proportion of sputum smear positive had remained unchanged (13.0%versus 12.6%;P value0.31).

Conclusion

Use of LED-FM significantly increased the proportion of smear positive cases among presumptive TB patients under routine program conditions in high workload laboratories. The study provides operational evidence needed to scale-up the use of LED-FM in similar settings in India and beyond.     

Synthesis and cytotoxic activity of heterocyclic ring-substituted betulinic acid derivatives

A new series of betulinic acid derivatives have been synthesized by introducing heterocyclic ring between C-2 and C-3 positions of betulinic acid. Further modifications were also carried out by reduction of C-20(29) unsaturated bond and substitution of C-28 carboxyl group by ester and amide linkage to enhance the selectivity. Compound 11 resulted in IC(50) of 2.44, 2.5, and 2.7 microg/ml on MIAPaCa, PA-1, and SW620 cancer cell lines, respectively. Compound 38 resulted in IC(50) of 0.67 microg/ml on MIAPaCa cell line.