Comparative assessment of two in-house-built isothermal assays for visual detection of African swine fever virus.

Owing to the lack of effective vaccines, current control measures and eradication strategies for the African swine fever virus (ASFV) rely on early detection and stringent stamping-out procedures. In the present study, we developed two independent isothermal amplification assays, namely, loop-mediated isothermal amplification (LAMP) and polymerase spiral reaction (PSR), for quick visualization of the ASFV genome in clinical samples. Additionally, a quantitative real-time PCR (qRT-PCR)-based hydrolysis probe assay was developed for comparative assessment of sensitivity with the developed isothermal assays. The analytical sensitivity of the LAMP, PSR, and qRT-PCR was found to be 2.64 ×105 copies/µL, 2.64 ×102 copies/µL, and 2.64 ×101 copies/µL, respectively. A total of 165 clinical samples was tested using the developed visual assays. The relative accuracy, relative specificity, and relative diagnostic sensitivity for LAMP vs PSR were found to be 95.37% vs 102.48%, 97.46% vs 101.36%, and 73.33% vs 113.33%, respectively.

Computational assessment of Withania somnifera phytomolecules as putative inhibitors of Mycobacterium tuberculosis CTP synthase PyrG.

Genome evolution of Mycobacterium tuberculosis (Mtb) produces new strains resistant to various pre-existing anti-tubercular drugs. Hence, there is an urgent need to explore potent compounds with the most negligible side effects and effective Mtb inhibition. Mtb PyrG (CTP synthase) is a crucial enzyme for the conversion of the uridine triphosphate (UTP) into cytidine triphosphate (CTP) and is essential for the growth of Mtb. Thus, in this study, phytochemicals of Withania somnifera (W. somnifera) were screened to find the potential inhibitors against Mtb PyrG. Molecular docking resulted in the identification of quercetin 3-rutinoside-7-glucoside, rutin, chlorogenic acid and isochlorogenic acid C with a substantial docking score (from -12.6 to -10.8 kcal/mol) contributed by significant intermolecular interactions. Furthermore, 100 ns molecular dynamics simulation, ADME analysis and free binding energy calculations support the stability of docked complexes and drug-likeness for selected compounds, respectively. Collectively, these findings suggest that phytochemicals present in W. somnifera can be considered for further evaluation against Mtb in a series of in vitro and in vivo models.Communicated by Ramaswamy H. Sarma.

Low-cost fabrication and characterization process for development of a sensitive optical fiber structure.

The structure of silica single-mode fiber (SMF) must be modified in order to develop optical fiber-based biosensors. To reduce the diameter of the optical fiber, a low-cost chemical etching method is very popular. The proposed chemical etching method is a simple, rapid, and cost-effective technique for removing the silica cladding up to a desired diameter. In the laboratory, hydrofluoric acid (HF acid, 40% concentration) is used for etching. A variation on etching is also proposed and tested with 40% HF as well as with magnetic stirring at the different speeds. The etching experiments are also carried out at different temperatures. The etching results of silica fiber are presented through a step-by-step procedure using a rapid and resource-efficient method for the fabrication of optical fiber-based biosensors. The etched diameter characterization is done using a calibrated compound microscope. The sensing experiment with unetched and etched optical fiber is also performed for the detection of different concentrations of glucose biomolecules.