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Introduction: Developing nations have a huge burden of tuberculosis (TB), because of which many cases are undetected and diagnosed only on autopsies. The purpose of this study was to find these cases in a series of consecutive autopsies conducted at a tertiary care centers., Materials and Methods: This retrospective study of 7-year duration from 2014 to 2020 consisted of reviewing 767 autopsies. The records of cases where a diagnosis of TB were established on histopathology were noted and evaluated., Results: Of 767 autopsies, TB was the diagnosis on histopathology in 72 cases. Of the 72 cases, 53 cases were undiagnosed antemortem and incidentally detected on autopsy. The study showed a male predominance with a 1.52:1 male-to-female ratio. The most common age group involved was the second decade. The study constitutes 26 cases of isolated pulmonary TB, 23 cases of disseminated TB, three cases of solitary renal TB, and one case of hepatic TB. The liver was the most commonly involved organ along with the lung in cases of disseminated TB, followed by the spleen, kidney, pancreas, intestine, brain, and heart., Discussion: Epidemiology and research on TB may be affected by these hidden cases which are unraveled incidentally on autopsy. These cases must always be reported and brought to the attention of clinicians for nation's better public health., Competing Interests: None

The main emphasis herein is on the eco-friendly synthesis and assessment of the antimicrobial potential of silver nanoparticles (AgNPs) and a cytotoxicity study. Silver nanoparticles were synthesised by an extracellular method using bacterial supernatant. Biosynthesised silver nanoparticles were characterised by UV-vis spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential analysis. The synthesised silver nanoparticles exhibited a characteristic peak at 420 nm. TEM analysis depicted the spherical shape and approximately 20 nm size of nanoparticles. Silver nanoparticles carry a charge of -33.75 mV, which confirms their stability. Biogenic polyvinyl pyrrolidone-coated AgNPs exhibited significant antimicrobial effects against all opportunistic pathogens (Gram-positive and Gram-negative bacteria, and fungi). Silver nanoparticles equally affect the growth of both Gram-positive and Gram-negative bacteria, with a maximum inhibition zone observed at 22 mm and a minimum at 13 mm against Pseudomonas aeruginosa and Fusarium graminearum, respectively. The minimum inhibitory concentration (MIC) of AgNPs against P. aeruginosa and Staphylococcus aureus was recorded at between 15 and 20 μg/ml. Synthesised nanoparticles exhibited a significant synergistic effect in combination with conventional antibiotics. Cytotoxicity estimates using C2C12 skeletal muscle cell line via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and lactate dehydrogenase assay were directly related to the concentration of AgNPs and length of exposure. On the basis of the MTT test, the IC50 of AgNPs for the C2C12 cell line was approximately 5.45 μg/ml concentration after 4 h exposure., (© 2021 The Authors. IET Nanobiotechnology published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.)

Emergence of resistant microbes to conventional antibiotics and increased emphasis on health-care costs has raised the concern for the development of new effective antimicrobial reagents. Silver nanoparticles being an excellent broad-spectrum antibacterial agent could be considered as a suitable alternative for existing antibiotic. This study demonstrates the extra-cellular synthesis of stable silver nanoparticles using supernatant of Lysinibacillus varians. The synthesized silver nanoparticles were characterized by using UV-visible spectrum analysis, X-ray diffraction, Transmission electron microscopy (TEM) and FT-IR analysis. The synthesized silver nanoparticles showed a peak around 420 nm. TEM analysis revealed that the size of silver nanoparticles was in the range of 10-20 nm. Silver nanoparticles carry a charge of -39.86 mV, which confirmed the stability of silver nanoparticles. The biologically synthesized silver nanoparticles showed antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. Therefore, the current study reveals an efficient and eco-friendly synthesis of silver nanoparticles by L. varians with potent antimicrobial activity.

Pseudomonas isolates obtained from the rhizosphere of chickpea (Cicer arietinum L.) and green gram (Vigna radiata) were found to produce significant amount of indole acetic acid (IAA) when grown in a LB medium broth supplemented with L-tryptophan. Seed bacterization of chickpea cultivar C235 with different Pseudomonas isolates showed stunting effect on the development of root and shoot at 5 and 10 days of seedling growth except the strains MPS79 and MPS90 that showed stimulation of root growth, and strains MPS104 and MRS13 that showed shoot growth stimulation at 10 days. Exogenous treatment of seeds with IAA at 0.5 and 1.0 μM concentration caused similar stunting effects on root and shoot growth compared to untreated control both at 5 and 10 days of observation, whereas higher concentration of IAA (10.0 μM) inhibited the growth of seedlings. Coinoculation of chickpea with IAA-producing Pseudomonas strains increased nodule number and nodule biomass by Mesorhizobium sp. Cicer strain Ca181. The plant dry weights of coinoculated treatments showed 1.10 to 1.28 times increase in comparison to Mesorhizobium-inoculated plants alone and 3.62 to 4.50 times over uninoculated controls at 100 days of plant growth. The results indicated the potential usefulness of allelopathic rhizosphere bacteria and growth-mediating IAA in enhancement of nodulation and stimulation of plant growth in chickpea.

Pseudomonas strains CPS63 and MPS78 produced 18.1 and 19.2 μg ml(-1) of indole acetic acid (IAA) at 2 days of growth. Low producers as well as over producer IAA mutants were derived from Pseudomonas strains CPS63 and MPS78 by Tn5 mutagenesis. Inoculation of selected IAA mutants on green gram (Vigna radiata) seeds showed stunting effect on root and shoot growth of seedlings at 5 and 10 days. Coinoculation studies of Pseudomonas strains with Bradyrhizobium strain S24 and IAA over producer mutants, i.e. CPS63-20 and MPS78-107 resulted in more nodule formation in green gram as compared to wild type Bradyrhizobium strain at 50 days of growth. Significant gains in plant dry weights, i.e. 2.0-3.06 times increase in comparison to uninoculated control plants, were observed on coinoculation of IAA low producer mutants CPS63-27, MPS78-92 and MPS78-166. Better performance of IAA low producer mutants in enhancing plant dry weights of green gram than to IAA over producer mutants indicated that overproduction of IAA by bacteria might inhibit shoot growth in green gram.

Rhizobacteria belonging to Bacillus sp. were isolated from the rhizosphere of chickpea (Cicer arietinum). Ten Bacillus strains were studied for their antifungal activity, effect on seedling emergence and plant growth promotion. Two Bacillus strains CBS127 and CBS155 inhibited the growth of all the four pathogenic fungi tested on nutrient agar medium plates in vitro. Seed inoculation with different Bacillus strains showed stimulatory effect on root and shoot growth at 10 d of observation in comparison to control whereas four Bacillus strains CBS24, CBS127, CBS129 and CBS155 caused retardation of shoot growth at 10 d. Maximum nodule-promoting effect was observed with Bacillus strains CBS106, CBS127 and CBS155. The symbiotic effectiveness of Mesorhizobium sp. Cicer strain Ca181 was further improved on coinoculation with six Bacillus strains i.e. CBS9, CBS17, CBS20, CBS106, CBS127 and CBS155 at 80 d of plant growth under sterile conditions and shoot dry weight ratios increased 1.62 to 1.74 times those of Mesorhizobium-inoculated treatments, suggesting the usefulness of introduced rhizobacteria in improving crop productivity.