Current understanding on micro RNAs and its regulation in response to Mycobacterial infections

MicroRNAs (miRNAs) are evolutionarily conserved, naturally abundant, small, regulatory non-coding RNAs that inhibit gene expression at the post-transcriptional level in a sequence-specific manner. Due to involvement in a broad range of biological processes and diseases, miRNAs are now commanding considerable attention. Although much of the focus has been on the role of miRNAs in different types of cancer, recent evidence also points to a critical role of miRNAs in infectious disease, including those of bacterial origin. Now, miRNAs research is exploring rapidly as a new thrust area of biomedical research with relevance to deadly bacterial diseases like Tuberculosis (caused by Mycobacterium tuberculosis). The purpose of this review is to highlight the current developments in area of miRNAs regulation in Mycobacterial diseases; and how this might influence the diagnosis, understanding of disease biology, control and management in the future

Mutations in rpoB gene and their association with Rifampicin resistance levels in clinical isolates of Mycobacterium tuberculosis

Present study was aimed to identify most frequent mutations in rpoB gene region and to evaluate the association between mutations in rpoB gene and resistance levels to Rifampicin in clinical isolates of Mycobacterium tuberculosis of different geographical regions of India. A total of 100 clinical isolates of Mycobacterium tuberculosis were included in this study. Drug susceptibility testing against first line anti-tuberculosis drugs was performed on LJ medium by conventional minimal inhibitory concentration (MIC) method and the mutation(s) in rpoB gene of M. tuberculosis isolates were analyzed by sequencing method. Of the 100 M. tuberculosis isolates, 31 (31.0%) and 18 (18.0%) were found resistant and susceptible for all four first-line anti-tuberculosis drugs. The genetic mutations were observed in 96% (72/75) rifampicin-resistant M. tuberculosis isolates, while 4% (3/75) of rifampicin resistant isolates did not have any mutation in rpoB gene. The mutation TCG531TTG (Ser531Leu) was found as most common and frequent mutation in 69.3% (52/75) of rifampicin resistant isolates of M. tuberculosis with MIC level (≥ 512mg/l). The mutation at codon 511 was associated with low degree (128mg/l) of rifampicin resistance, deletions at codons 514-516 or substitution at codon 516 were found to be associated with moderate degree (256mg/l) of rifampicin resistance and mutations at codon 526, 531 were associated with the high degree (512mg/l) of rifampicin resistance in M. tuberculosis isolates of Indian origin. The findings of this study will be useful for the development of raid and more specific indigenous molecular tools for the early diagnosis of multidrug-resistant tuberculosis in the country.

STUDIES ON MICROBIOLOGICAL QUALITY OF SPROUTS OF MUNG BEAN (VIGNA RADIATE L.)

Sprouts are now well known for their high nutritive value and digestibility. They are rich in enzymes, bioavailable vitamins, minerals, amino acids and fibers. Sprouts are low in fat and calories, being rich in nutrients and known to promote health, sprouts now a days are available in most of the grocery stalls. Survey of sprouted seeds available at retail venders has shown the presence of pathogenic bacteria like E. coli 0157, Salmonella and Listeria monocytogens, which is of concern for health conscious public. In the present study an attempt has been made to identify and examine the microorganisms present in seed sprouts of mung bean. Key Words: Mung Bean Sprouts, Morphological Identification, Biochemical Characteristics

Mutations in RpoB Gene and Their Association with Rifampicin-resistance Levels in Clinical Isolates of Mycobacterium Tuberculosis

Present study was aimed to identify most frequent mutations in rpoB gene region and to evaluate the association between mutations in rpoB gene and resistance levels to Rifampicin in clinical isolates of Mycobacterium tuberculosis of different geographical regions of India. A total of 100 clinical isolates of Mycobacterium tuberculosis were included in this study. Drug susceptibility testing against first line anti-tuberculosis drugs was performed on LJ medium by conventional minimal inhibitory concentration (MIC) method and the mutation(s) in rpoB gene of M. tuberculosis isolates were analyzed by sequencing method. Of the 100 M. tuberculosis isolates, 31 (31.0%) and 18 (18.0%) were found resistant and susceptible for all four first-line anti-tuberculosis drugs. The genetic mutations were observed in 96% (72/75) rifampicin-resistant M. tuberculosis isolates, while 4% (3/75) of rifampicin-resistant isolates did not have any mutation in rpoB gene. The mutation TCG531TTG (Ser531Leu) was found as most common and frequent mutation in 69.3% (52/75) of rifampicin-resistant isolates of M. tuberculosis with MIC level (≥ 512mg/l). The mutation at codon 511 was associated with low degree (128mg/l) of rifampicin-resistance, deletions at codons 514-516 or substitution at codon 516 were found to be associated with moderate degree (256mg/l) of rifampicin-resistance and mutations at codon 526, 531 were associated with the high degree (512mg/l) of rifampicin-resistance in M. tuberculosis isolates of Indian origin. The findings of this study will be useful for the development of raid and more specific indigenous molecular tools for the early diagnosis of multidrug-resistant tuberculosis in the country

Assessment of the N-PCR Assay in Diagnosis of Pleural Tuberculosis: Detection of M.tuberculosis in Pleural Fluid and Sputum Collected in Tandem

The nonspecific clinical presentation and paucibacillary nature of tuberculous pleuritis remains a challenge for diagnosis. Diagnosis of tuberculous pleural effusion depends on the demonstration of the presence of tubercle bacilli in the sputum, pleural fluid, or pleural biopsy specimen, or demonstration of granuloma in pleura by histological examination. We examined the clinical utility of the diagnosis of pleural tuberculosis using the in house N-PCR assay, AFB smear microscopy and culture. Besides pleural fluid the inclusion of sputum in the efficacy of diagnosis of pleural tuberculosis was scrutinized.Pleural fluid and sputum samples of 58 tuberculous and 42 non-tuberculous pleural effusion patients were processed for AFB smear microscopy, culture and the N-PCR assay. Mycobacteria were detected exclusively in tuberculous pleural effusion samples. None of the non-tuberculous pleural effusion samples were positive for mycobacteria. Comparative analysis showed that the N-PCR assay had the highest sensitivity. Inclusion of sputum along with pleural fluid increased N-PCR sensitivity from 51.7 to 70.6% (p<0.0001).This improved sensitivity was reflected in AFB smear microscopy and isolation by culture. The sensitivity enhanced on inclusion of sputum from 3.4 (p = 0.50) to 10.3% (p = 0.038) for AFB smear microscopy and for isolation of mycobacteria from 10.3(p = 0.03) to 22.4% (p = 0.0005). Thirteen isolates were obtained from 58 pleural tuberculosis patients. Eleven mycobacterial isolates were identified as M. tuberculosis and two as M. fortuitum and M. chelonae. Complete concordance was seen between the biochemical identification of isolates and the N-PCR identification of mycobacterial species prior to isolation.To the best of our knowledge this is the first PCR based report on utility of sputum for diagnosis of pleural tuberculosis. The present study demonstrates that a combination of pleural fluid with sputum sample and N-PCR improved the diagnosis of pleural tuberculosis

Prevalence and genotypes of Mycobacterium avium subspecies paratuberculosis in large ruminants of Eastern Uttar Pradesh, North India

Uttar Pradesh is the fourth largest, most populous and leading milk and meat producing state in India. Despite the huge livestock population, information on the status of paratuberculosis homogeneity and heterogeneity of Mycobacterium avium subspecies paratuberculosis (MAP) isolates of eastern Uttar Pradesh is non-existent. Present study was aimed to estimate the presence of MAP in large ruminants (Cattle and Buffaloes) of eastern Uttar Pradesh. A total 108 fecal samples were collected from farmer’s herds of large ruminants (cattle and buffaloes) from different geographical regions (Chandauli, Mughalsarai, Gazipur, and Naugarh) of eastern Uttar Pradesh and screened for the presence of MAP infection using microscopic examination, direct IS900 PCR and culture on Herrold egg yolk (HEY) medium. The isolates recovered on HEY medium were subjected to molecular identification and genotyping using IS900 PCR and IS1311 PCR-REA method, respectively. Of the 108 fecal samples, 25 (23.14%) and 11 (10.18%) samples were positive for the presence of acid-fast bacilli and growth on HEY medium, respectively. Species-wise, 17.5, 7.5% and 26.5, 11.7% fecal samples from cattle and buffaloes were found positive for the presence of acid-fast bacilli and growth on HEY medium, respectively. Isolates recovered on HEY medium with mycobactin J were positive for IS900 sequence and genotyped as Bison Type using IS1311 PCR-REA method. Present study is the first report on the presence of MAP infection and ‘Bison Type’ genotype of MAP in eastern Uttar Pradesh. These findings will be useful for the intervention of effective control measures in order to reduce the prevalence of MAP infection in domestic livestock species and prevent its spread to the human population in the regions

Electromagnetic interference shielding performance of carbon nanostructure reinforced, 3D printed polymer composites

We report the electrical, mechanical and electromagnetic interference (EMI) shielding performance of polypropylene random copolymer (PPR)/multi-wall carbon nanotube (MWCNT) nanocomposites enabled via customized fused filament fabrication process. The electro-conductive PPR/MWCNT filament feedstocks were fabricated via shear-induced melt-blending process that allows 3D printing of nanoengineered composites even at higher MWCNT loading (up to 8 wt%). The uniform dispersion of MWCNTs in PPR matrix confirmed via Raman spectroscopy and scanning electron microscopy facilitates better mechanical, electrical and EMI shielding performance. The results furthermore show enhanced shielding properties and higher attenuation for the nanocomposites printed in 90° direction (~ − 37 dB for 8 wt% MWCNT loading). Effective interfacial adhesion between the beads with lesser extent of voids (confirmed via micro-computed tomography) endorsed low transmission loss in nanocomposites printed in 90° direction compared to samples printed in 0° direction. Surface architected structure (frustum shape) reveals higher specific shielding effectiveness (maximum ~ − 40 dBg−1cm3, + 38%) over the plain structure. The realization of excellent shielding effectiveness (~ 99.9% attenuation) of additive manufacturing-enabled PPR/MWCNT nanocomposites demonstrates their potential for lightweight and strong EMI shields

Prevalence and Genotypes of Mycobacterium Avium Subspecies Paratuberculosis in Large Ruminants of Eastern Uttar Pradesh, North India

Uttar Pradesh is the fourth largest, most populous and leading milk and meat producing state in India. Despite the huge livestock population, information on the status of paratuberculosis homogeneity and heterogeneity of Mycobacterium avium subspecies paratuberculosis (MAP) isolates of eastern Uttar Pradesh is non-existent. Present study was aimed to estimate the presence of MAP in large ruminants (Cattle and Buffaloes) of eastern Uttar Pradesh. A total 108 fecal samples were collected from farmer's herds of large ruminants (cattle and buffaloes) from different geographical regions (Chandauli, Mughalsarai, Gazipur, and Naugarh) of eastern Uttar Pradesh and screened for the presence of MAP infection using microscopic examination, direct IS900 PCR and culture on Herrold egg yolk (HEY) medium. The isolates recovered on HEY medium were subjected to molecular identification and genotyping using IS900 PCR and IS1311 PCR-REA method, respectively. Of the 108 fecal samples, 25 (23.14%) and 11 (10.18%) samples were positive for the presence of acid-fast bacilli and growth on HEY medium, respectively. Species-wise, 17.5, 7.5% and 26.5, 11.7% fecal samples from cattle and buffaloes were found positive for the presence of acid-fast bacilli and growth on HEY medium, respectively. Isolates recovered on HEY medium with mycobactin J were positive for IS900 sequence and genotyped as Bison Type using IS1311 PCR-REA method. Present study is the first report on the presence of MAP infection and ‘Bison Type' genotype of MAP in eastern Uttar Pradesh. These findings will be useful for the intervention of effective control measures in order to reduce the prevalence of MAP infection in domestic livestock species and prevent its spread to the human population in the regions

Revisiting Prostate Cancer in India: A Genomic View

In the recent past, there has been a rise in Prostate Cancer (PCa) in Asia, particularly India.  Although systematic reviews on PCa have dealt on the genetics, genomics and the environmental influence in causal of PCa, no predictive analytics in comparing the PCa from Caucasian, American to Asian population was attempted. In this review article, we have attempted to elaborate this aspect of PCa and deliberated on challenges related to next generation sequencing methods of PCa’s manifestation when compared to the west

Whole Genome Sequencing of Mycobacterium tuberculosis Clinical Isolates From India Reveals Genetic Heterogeneity and Region-Specific Variations That Might Affect Drug Susceptibility

Whole genome sequencing (WGS) of Mycobacterium tuberculosis has been constructive in understanding its evolution, genetic diversity and the mechanisms involved in drug resistance. A large number of sequencing efforts from across the globe have revealed genetic diversity among clinical isolates and the genetic determinants for their resistance to anti-tubercular drugs. Considering the high TB burden in India, the availability of WGS studies is limited. Here we present, WGS results of 200 clinical isolates of M. tuberculosis from North India which are categorized as sensitive to first-line drugs, mono-resistant, multi-drug resistant and pre-extensively drug resistant isolates. WGS revealed that 20% of the isolates were co-infected with M. tuberculosis and non-tuberculous mycobacteria species. We identified 12,802 novel genetic variations in M. tuberculosis isolates including 343 novel SNVs in 38 genes which are known to be associated with drug resistance and are not currently used in the diagnostic kits for detection of drug resistant TB. We also identified M. tuberculosis lineage 3 to be predominant in the northern region of India. Additionally, several novel SNVs, which may potentially confer drug resistance were found to be enriched in the drug resistant isolates sampled. This study highlights the significance of employing WGS in diagnosis and for monitoring further development of MDR-TB strains