Elucidating the structural, anticancer, and antibacterial traits of Punica granatum peel extracts-mediated Ag and Ag/GO nanocomposites.

Ag nanoparticles and Ag/GO nanocomposites have been synthesized by facile, eco-friendly, and cost-effective green approach using the peel extracts of Punica granatum. The synthesized Silver Nanoparticles and Silver Graphene Oxide nanocomposites were characterized by UV-visible spectroscopy, X-ray diffraction, transmission electron microscopy, and Fourier transform infrared analysis. AgNPs revealed spherical morphology with particle size ranging from 30 to 40 nm. Scanning electron microscopy results revealed silver nanoparticles with an average size of 35 nm being uniformly distributed over GO sheets. The surface plasmon band appears at 433 nm for AgNPs and 458 nm for Ag/GO nanocomposites. The green synthesized nanoparticles were found to have excellent antibacterial efficacy against both gram positive (Staphylococcus aureus, Bacillus subtilis) and gram negative (Klebsiella pneumoniae, Escherichia coli) bacterial strains. The results showed that Ag/GO nanocomposites showed better antibacterial activity than pure AgNPs with maximum inhibitory zone of 28 mm for Escherichia coli. This attributes to the role of GO sheets in preventing AgNPs from agglomerating and oxidizing. The anticancer activity of AgNPs and Ag/GO nanocomposites were tested against human breast cancer cell line (MCF-7) which demonstrated a dose dependent activity with half minimum inhibitory concentration of 100 and 150 µg/ml.

Clinico-pathological features in fatal COVID-19 infection: a preliminary experience of a tertiary care center in North India using postmortem minimally invasive tissue sampling.

OBJECTIVES: To study the histopathology of patients dying of COVID-19 using post-mortem minimally invasive sampling techniques. METHODS: This was a single-center observational study conducted at JPNATC, AIIMS. Thirty-seven patients who died of COVID-19 were enrolled. Post-mortem percutaneous biopsies were taken from lung, heart, liver, kidney and stained with hematoxylin and eosin. Immunohistochemistry was performed using CD61 and CD163. SARS-CoV-2 virus was detected using IHC with primary antibodies. RESULTS: The mean age was 48.7 years and 59.5% were males. Lung histopathology showed diffuse alveolar damage in 78% patients. Associated bronchopneumonia was seen in 37.5% and scattered microthrombi in 21% patients. Immunopositivity for SARS-CoV-2 was observed in Type II pneumocytes. Acute tubular injury with epithelial vacuolization was seen in 46% of renal biopsies. Seventy-one percent of liver biopsies showed Kupffer cell hyperplasia and 27.5% showed submassive hepatic necrosis. CONCLUSIONS: Predominant finding was diffuse alveolar damage with demonstration of SARS-CoV-2 protein in the acute phase. Microvascular thrombi were rarely identified in any organ. Substantial hepatocyte necrosis, Kupffer cell hypertrophy, microvesicular, and macrovesicular steatosis unrelated to microvascular thrombi suggested that liver might be a primary target of COVID-19.