Evaluation of antipyretic activity of leaf extracts of Mallotus peltatus (Geist) Muell. arg. var acuminatus: a folk medicine.

A study was carried out to evaluate the anti-pyretic potential of the methanol extract of Mallotus peltatus (Geist) Muell. Arg. var acuminatus leaf, a folk medicine of Onge tribes of Bay Islands, on normal body temperature and yeast-induced pyrexia in Wister albino rats. The leaf extract at oral doses of 100, 200 and 300 mg kg(-1), p.o., showed significant reduction in normal body temperature and yeast-provoked elevated temperature in a dose-dependent manner and the anti-pyretic effect was comparable to that of standard anti-pyretic agent paracetamol (150 mg kg(-1), p.o.). The effect also extended up to 5 hours after the drug administration.     

Synthesis of c-2, 3, 17 and 19-oxygenated androgens

The synthesis of C19-androgens oxygenated at carbons 2, 3, 17 and 19 and of their deuterium or deuterium-tritium labeled analogs is described.     

Assemblage structure of stream fishes in the Western Ghats (India)

Macro and microhabitat analyses were applied to characterise the fish assemblage structure in 10 streams of the Western Ghat mountains of Peninsular India. Macrohabitat features, such as channel gradient, stream depth, stream width, riparian cover, instream cover, habitat types and substrates, were used. Microhabitat requirements of the abundant cyprinids (35 species) were also analysed. Macrohabitat assessment indicated that a high habitat diversity was associated with a high species diversity, and that habitat volume was a major determining factor for species diversity and abundance. In all streams, cyprinids were the dominant group in the assemblage and almost all cyprinids were confined to pools with a varied habitat diversity. Riffle dwelling species included ancient forms such as Glyptothorax madraspatnum, G. trewasae and Homaloptera santhamparaiensis. Suitable microhabitats for dominant cyprinid species were pools and riffle edges. Big-sized barbs and mahseers such as Hypselobarbus dobsoni, H. curmuca, H. dubius, Labeo calbasu, Puntius sarana, Tor khudree and Tor khudree malabaricus were confined to deep pools with a large area. Smaller Puntius species like P. fasciatus, P. melanampyx, P. narayani, P. sophore, P. ticto and P. vittatus lived in shallow backwater pools and pools with low flow. Species like P. arulius tambiraparniei, P. amphibius, P. bimaculatus and P. filamentosus were found towards shallow pools with moderate flow. Surface-dwelling species such as Danio aequipinnatus, Rasbora daniconius, Salmostoma spp. and Barilius spp. preferred deepwater habitats with high flow. Habitat-based multivariate analysis revealed four guilds: surface dwellers, column dwellers, generalized bottom dwellers and specialized bottom dwellers.     

Assessment of antibacterial activity of silver nanoparticles on Pseudomonas aeruginosa and its mechanism of action

Antimicrobial activity of silver nanoparticles is gaining importance due its broad spectrum of targets in cell compared to conventional antimicrobial agents. In this context, a UV photo-reduction method was used for the synthesis and the nanoparticles were characterized by UV–Visible spectroscopy, transmission electron microscopy, atomic force microscopy and thermogravimetric analysis techniques. The antibacterial activity of the synthesized silver nanoparticles was evaluated both in liquid and solid growth media employing various susceptibility assays on Pseudomonas aeruginosa, a ubiquitous bacterium. The dose dependent growth suppression by nanoparticles was studied with well diffusion method. By broth dilution method, the minimum inhibitory concentration (MIC) was found to be 2 μg/ml. It was observed that the bactericidal effect depends both on nanoparticle concentration and number of bacteria present. In our study, we could demonstrate the complete antibiofilm activity of silver nanoparticles at a concentration as low as 1 μg/ml. Our observations substantiated the association of reactive oxygen species and cell membrane damage in the antibacterial mechanism of silver nanoparticles. Our findings suggested that these nanoparticles can be exploited towards the development of potential antibacterial coatings for various biomedical and environmental applications.     

Microsatellites in palm (Arecaceae) sequences

Microsatellites are the most promising co-dominant markers, widely distributed throughout the genome. Identification of these repeating genomic subsets is a tedious and iterative process making computational approaches highly useful for solving this biological problem. Here 38,083 microsatellites were localized in palm sequences. A total of 2, 97,023 sequences retrieved from public domains were used for this study. The sequences were unstained using the tool Seqclean and consequently clustered using CAP3. SSRs are located in the sequences using the microsatellite search tool, MISA. Repeats were detected in 33,309 sequences and more than one SSR had appeared in 3,943 sequences. In the present study, dinucleotide repeats (49%) were found to be more abundant followed by mononucleotide (30%) and trinucleotide (19%). Also among the dinucleotides, AG/GA/TC/CT motifs (55.8%) are predominantly repeating within the palm sequences. Thus in future this study will lead to the development of specific algorithm for mining SSRs exclusively for palms.     

Glutathione S-transferase pi (GST-pi) inhibition and anti-inflammation activity of the ethyl acetate extract of Streptomyces sp. strain MJM 8637

To investigate the anti-cancer properties of soil-borne actinobacteria, MJM 8637, the glutathione S-transferase pi (GST-pi) assay, anti-tumor necrosis factor (TNF)-α assay, the level of antioxidant potential by DPPH radical scavenging activity, NO scavenging activity, and ABTS radical scavenging activity in ethyl acetate extract were determined. The 16S rDNA sequencing analysis revealed that Streptomyces sp. strain MJM 8637, which was isolated from Hambak Mountain, Korea, has 99.5% similarity to Streptomyces atratus strain NBRC 3897. The physiological and the morphological characteristics of the strain MJM 8637 were also identified. The ethyl acetate extract of MJM 8637 inhibited TNF-α production approximately 61.8% at concentration 100 μg/ml. The IC₅₀ value of the strain MJM 8637 extract on GST-pi was identified to be 120.2 ± 1.6 μg/ml. In DPPH, NO, and ABTS radical scavenging assays, the IC₅₀ values of the strain MJM 8637 extract were found to be 977.2 μg/ml, 1143.7 μg/ml, and 454.4 μg/ml, respectively. The ethyl acetate extract of the strain MJM 8637 showed 97.2 ± 1.3% of cell viability at 100 μg/ml in RAW 264.7 cell viability assay. The results obtained from this study suggest that the ethyl acetate extract of Streptomyces sp. strain MJM 8637 could be considered as a potential source of drug for the cancers that have multidrug resistance with its GST-pi inhibition and anti-inflammation activities, and low cytotoxicity.     

Probiotic Characterization of Lactobacillus paracasei subsp. paracasei KNI9 Inhibiting Adherence of Yersinia enterocolitica on Caco-2 Cells In Vitro

The study was aimed to characterize the probiotic properties of Lactobacillus paracasei subsp. paracasei strain KNI9 and its antagonistic activity against Yersinia enterocolitica subsp. enterocolitica. The strain KNI9 was susceptible to antibiotics such as chloramphenicol, tetracycline, erythromycin, and streptomycin recommended by European food safety authority (EFSA). Strain KNI9 exhibited tolerance to simulated oro-gastrointestinal (OGT) condition, adherence to Caco-2 cells, and antimicrobial activity against intestinal enteric pathogens such as Yersinia enterocolitica subsp. enterocolitica, Shigella boydii, and Listeria monocytogenes. Furthermore, the strain KNI9 inhibited the adherence and invasiveness of Y. enterocolitica subsp. enterocolitica to Caco-2 cell line. These results indicate that the L. paracasei subsp. paracasei KNI9 could be further developed into a potential probiotic strain after appropriate in vivo studies.

     

The C3/465 glycan hole cluster in BG505 HIV-1 envelope is the major neutralizing target involved in preventing mucosal SHIV infection

Stabilized HIV-1 envelope (Env) trimers elicit tier 2 autologous neutralizing antibody (nAb) responses in immunized animals. We previously demonstrated that BG505 SOSIP.664.T332N gp140 (BG505 SOSIP) immunization of rhesus macaques (RM) provided robust protection against autologous intra-vaginal simian-human immunodeficiency virus (SHIV) challenge that was predicted by high serum nAb titers. Here, we show that nAb in these protected RM targeted a glycan hole proximal to residue 465 in gp120 in all cases. nAb also targeted another glycan hole at residues 241/289 and an epitope in V1 at varying frequencies. Non-neutralizing antibodies directed at N611-shielded epitopes in gp41 were also present but were more prevalent in RM with low nAb titers. Longitudinal analysis demonstrated that nAb broadened in some RM during sequential immunization but remained focused in others, the latter being associated with increases in nAb titer. Thirty-eight monoclonal antibodies (mAbs) isolated from a protected RM with an exceptionally high serum neutralization titer bound to the trimer in ELISA, and four of the mAbs potently neutralized the BG505 Env pseudovirus (PV) and SHIV. The four neutralizing mAbs were clonally related and targeted the 465 glycan hole to varying degrees, mimicking the serum. The data demonstrate that the C3/465 glycan hole cluster was the dominant neutralization target in high titer protected RM, despite other co-circulating neutralizing and non-neutralizing specificities. The isolation of a neutralizing mAb family argues that clonotype expansion occurred during BG505 SOSIP immunization, leading to high titer, protective nAb and setting a desirable benchmark for HIV vaccines.