Showing papers by "Abhay Chowdhary published in 2020"
TL;DR: A series of substituted flavones and aurones as non-competitive H1N1 neuraminidase (NA) inhibitors and anti-influenza agents are designed and synthesized and kinetic studies illustrated that compounds 1f and 2f had non- competitive inhibition mechanism.
15 citations
TL;DR: Development of an in-house whole genome sequencing (WGS) assay and bioinformatics pipeline that helped resolve the phenotype-genotype discrepancy in a clinical isolate is reported, indicating a highly sensitive, specific, and unbiased approach for identification of all possible drug resistance-conferring mutations.
Abstract: Background Mycobacterium tuberculosis (Mtb) drug resistance is a global concern. Moreover, multiple drug resistant (MDR), extensively drug resistant (XDR), and totally drug resistant (TDR) Mtb cases are on the rise in developing countries like India. Most of these cases are identified only 3–6 months after initiation of treatment owing to incomplete/failed clinical response and incomplete information from phenotypic drug resistance assays and/or targeted Mtb mutation analysis. Here, we report the development of an in-house whole genome sequencing (WGS) assay and bioinformatics pipeline that helped resolve the phenotype-genotype discrepancy in a clinical isolate. Methodology and results A sample from a suspected drug resistant Mtb case tested by line probe assay (LPA) showed the absence of both the mutant and wild type alleles for an rpoB gene mutation site. An in-house next generation sequencing (NGS) assay was used for WGS of this isolate. Bioinformatics analysis revealed that the isolate harboured a novel insertional mutation in the 81-bp hotspot region of the rpoB gene and a S315T mutation in the katG gene, which could explain resistance to rifampicin and isoniazid, respectively. These results correlated with the clinical diagnosis, LPA, solid culture drug susceptibility testing, and pyrosequencing carried out on the sample. The WGS data also provided information regarding the isolate’s lineage and indicated an absence of known mutations conferring resistance to other antitubercular drugs. Conclusion WGS is a highly sensitive, specific, and unbiased approach for identification of all possible drug resistance-conferring mutations, which can help clinicians make more informed treatment-related decisions.
9 citations
TL;DR: HIV‐1‐infected patients develop haematological disorders such as cytopenias and it is hypothesised that there may be viral encoded, or host cellular factors which participate in the process of inhibition of haem atopoiesis.
Abstract: Introduction HIV-1-infected patients develop haematological disorders such as cytopenias. One possible explanation is the inhibition of haematopoiesis at the level of differentiation of CD34+ haematopoietic progenitor stem cells. Based on our previous studies, we hypothesised that there may be viral encoded, or host cellular factors which participate in the process of inhibition of haematopoiesis. Materials and methods Virus-depleted media from infected CD4+ T cells was prepared by filtration and added to CD34+ cell differentiation semisolid medium. We have also used the virus-depleted media to isolate host/viral factors including miRNA. Isolated miRNAs were screened for their haematopoietic inhibitory function using the miRNA mining approach. Results Addition of virus-depleted media caused a 40% inhibition of differentiation of CD34+ cells into myeloid and erythroid colony formation. Real-time RT-PCR showed miR-15a and miR-24 from both pIndie-C1 and pNL4.3 HIV-1-infected cells showed a significant differential expression when compared to control media. Conclusion In this study, we have identified two miRNAs, miR-15a and miR-24 secreted from purified HIV-1-infected CD4+ T cells that inhibited CD34+ haematopoietic progenitor stem cell differentiation into myeloid and erythroid colonies in vitro.
4 citations
TL;DR: MALDI-TOF MS-based identification is both a rapid and a viable tool for identification of clinically relevant yeast species with good correlation to conventional methods and a quick turnaround time.
Abstract: Background: India, being a country where fungal infections are rampant, is urgently in need of effective tools for early and accurate diagnosis of fungal infections. Matrix-assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) is a recent method which has shown potential in identifying clinically important bacterial pathogens as well as clinically important fungi. The main objective of this study was to compare the utility of MALDI-TOF MS for the identification of fungi against that of conventional methods. Methods: The project was carried out in a tertiary care government hospital in India. Fifty clinical isolates comprising mainly various yeast species were subjected to conventional identification (Phenotypic) as well as MALDI-TOF-MS. Their results were further compared. Results: MALDI-TOF MS showed a high concordance with conventional methods while identifying species like C. albicans, C. tropicalis, C. parapsilosis and C. neoformans, although the concordance for species such as Rhodotorula and Trichosporon could only be matched up to genus level. Conclusions: MALDI-TOF MS-based identification is both a rapid and a viable tool for identification of clinically relevant yeast species with good correlation to conventional methods and a quick turnaround time.
2 citations