Evaluation of biogenically synthesized MgO NPs anticancer activity against breast cancer cells.

Background: Magnesium is recognized to have pharmacological potential, and its nanoformulation is anticipated to offer significant therapeutic effects, particularly against cancer. In this study, we analyzed the anticancer effect of biogenically synthesized magnesium oxide nanoparticles (MgO NPs) against breast cancer cells (MDA-MB-231). Methods: Different biological evaluations, such as cytotoxicity, cellular morphology, induction of apoptosis, generation of ROS, cell adhesion and cellular migration were estimated using well established methodology. Results: The biogenic MgO NPs exhibited increased cytotoxicity, induced apoptosis, enhanced formation of ROS, promoted cell adhesion and inhibited cellular migration in a dose-dependent manner, showing its therapeutic potential against MDA-MB-231 cells. Conclusion: The current study observed strong anticancer activity of MgO NPs against studied cancer cell lines. However, our study must be validated in an appropriate animal/xenograft model to authenticate the effectiveness of MgO NPs against breast cancer.

COVID-19 infection, and reinfection, and vaccine effectiveness against symptomatic infection among health care workers in the setting of omicron variant transmission in New Delhi, India.

Background: Surge of SARS CoV-2 infections ascribed to omicron variant began in December 2021 in New Delhi. We determined the infection and reinfection density in a cohort of health care workers (HCWs) along with vaccine effectiveness (VE) against symptomatic infection within omicron transmission period (considered from December 01, 2021 to February 25, 2022. Methods: This is an observational study from the All India Institute of Medical Sciences, New Delhi. Data were collected telephonically. Person-time at risk was counted from November 30, 2021 till date of infection/ reinfection, or date of interview. Comparison of clinical features and severity was done with previous pandemic periods. VE was estimated using test-negative case-control design [matched pairs (for age and sex)]. Vaccination status was compared and adjusted odds ratios (OR) were computed by conditional logistic regression. VE was estimated as (1-adjusted OR)X100-. Findings: 11474 HCWs participated in this study. The mean age was 36⋅2 (±10⋅7) years. Complete vaccination with two doses were reported by 9522 (83%) HCWs [8394 (88%) Covaxin and 1072 Covishield (11%)]. The incidence density of all infections and reinfection during the omicron transmission period was 34⋅8 [95% Confidence Interval (CI): 33⋅5-36⋅2] and 45⋅6 [95% CI: 42⋅9-48⋅5] per 10000 person days respectively. The infection was milder as compared to previous periods. VE was 52⋅5% (95% CI: 3⋅9-76⋅5, p = 0⋅036) for those who were tested within 14-60 days of receiving second dose and beyond this period (61-180 days), modest effect was observed. Interpretation: Almost one-fifth of HCWs were infected with SARS CoV-2 during omicron transmission period, with predominant mild spectrum of COVID-19 disease. Waning effects of vaccine protection were noted with increase in time intervals since vaccination. Funding: None.