Hemolytic activity of and lethal toxin production by environmental strains of Vibrio parahaemolyticus.

Repeated subculturing of Kanagawa-negative strains of Vibrio parahaemolyticus on Wagatsuma agar induced the production of a hemolysin which was not the thermostable direct hemolysin. Crude hemolysin exhibited a 30 to 40% lethal toxicity in mice after intraperitoneal injection. A 21-kilodalton protein band was observed with all the environmental isolates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Results suggested that a certain percentage of environmental strains of V. parahaemolyticus is responsible for pathogenesis.     

Isolation and characterization of polyadenylate-containing RNA from Bacillus brevis.

A substantial fraction (30--40%) of pulse-labeled RNA from exponentially growing cells of Bacillus brevis contains polyadenylate sequences, as measured by adsorption to oligo(dT)-cellulose. The weight-average length of poly(A) tracts obtained after digestion with pancreatic and T1 ribonucleases is 60 nucleotide residues. Susceptibility to degradation by snake venom phosphodiesterase after ribonuclease degradation indicates that the poly(A) sequences are located near the 3' ends of the RNA chains, but that in 40% of the material at least one internal pyrimidine nucleotide residue intervenes between the poly(A) tract and the 3'-hydroxyl terminus. These pyrimidine nucleotides consist of 65% cytidylate and 35% uridylate residues. In the remaining RNA chains, the poly(A) sequence is directly at the 3'-terminus, but the possibility cannot be excluded that a small fraction of this material may contain a 3'-hydroxyl terminal guanylate residue. The weight-average sedimentation coefficient of poly(A)-containing RNA is 12.5 S, corresponding to a polynucleotide chain length of 800--900 residues. This is in a size range expected for messenger RNA, a possibility which is also supported by the observation that pulse-labeled RNA has a considerably higher poly(A) content than long-term labeled RNA.     

Synthesis of the anomers of methyl 2-acetamido-2-deoxy-d-galacto-furanoside and -pyranoside

On treatment with methanol in the presence of Amberlite IR-120 (H⁺) resin, 2-acetamido-2-deoxy-d-galactose yielded a mixture of four isomers, the methyl 2-acetamido-2-deoxy-α- and -β-d-galactofuranosides and their corresponding pyranosides. The isomers were separated preparatively on Dowex-1 ion-exchange resin, and analytically by high-pressure liquid chromatography, and identified by their m.p. and specific rotation and by assays of periodate uptake and formaldehyde liberated.     

Recent Advances in Biomaterial-Based High-Throughput Platforms

High-throughput systems allow screening and analysis of large number of samples simultaneously under same conditions. Over recent years, high-throughput systems have found applications in fields other than drug discovery like bioprocess industries, pollutant detection, material microarrays, etc. With the introduction of materials in such HT platforms, the screening system has been enabled for solid phases apart from conventional solution phase. The use of biomaterials has further facilitated cell-based assays in such platforms. Here, the authors have focused on the recent developments in biomaterial-based platforms including the fabricationusing contact and non-contact methods and utilization of such platforms for discovery of novel biomaterials exploiting interaction of biological entities with surface and bulk properties. Finally, the authors have elaborated on the application of the biomaterial-based high-throughput platforms in tissue engineering and regenerative medicine, cancer and stem cell studies. The studies show encouraging applications of biomaterial microarrays. However, success in clinical applicability still seems to be a far off task majorly due to absence of robust characterization and analysis techniques. Extensive focus is required for developing personalized medicine, analytical tools and storage/shelf-life of cell laden microarrays.     

Potent anti-mycobacterial and immunomodulatory activity of some bioactive molecules of Indian ethnomedicinal plants that have the potential to enter in TB management

Tuberculosis (TB) is one of the deadliest infectious diseases of human civilization. Approximately one-third of global population is latently infected with the TB pathogen Mycobacterium tuberculosis (M.tb). The discovery of anti-TB antibiotics leads to decline in death rate of TB. However, the evolution of antibiotic-resistant M.tb-strain and the resurgence of different immune-compromised diseases re-escalated the death rate of TB. WHO has already cautioned about the chances of pandemic situation in TB endemic countries until the discovery of new anti-tubercular drugs, that is, the need of the hour. Analysing the pathogenesis of TB, it was found that M.tb evades the host by altering the balance of immune response and affects either by killing the cells or by creating inflammation. In the pre-antibiotic era, traditional medicines were only therapeutic measures for different infectious diseases including tuberculosis. The ancient literatures of India or ample Indian traditional knowledge and ethnomedicinal practices are evidence for the treatment of TB using different indigenous plants. However, in the light of modern scientific approach, anti-TB effects of those plants and their bioactive molecules were not established thoroughly. In this review, focus has been given on five bioactive molecules of different traditionally used Indian ethnomedicinal plants for treatment of TB or TB-like symptom. These compounds are also validated with proper identification and their mode of action with modern scientific approaches. The effectiveness of these molecules for sensitive or drug-resistant TB pathogen in clinical or preclinical studies was also evaluated. Thus, our specific aim is to highlight such scientifically validated bioactive compounds having anti-mycobacterial and immunomodulatory activity for future use as medicine or adjunct-therapeutic molecule for TB management.