Electron transfer from CdSe-ZnS core-shell quantum dots to cobalt(III) complexes.

Fluorescence quenching of CdSe-ZnS quantum dots (core-shell QDs) is shown to be affected in the presence of cobalt(III) complexes with pyridyl anchors. Steady-state and time-resolved fluorescence spectra indicate that the quenching has primarily a static component. The decrease in photoluminescence intensity can be best explained by charge transfer from the QDs to the Co(III) complexes whereas the energy transfer pathways have been methodically ruled out. The fact that quenching is a result of electron transfer is also supported by electrochemical data showing the positions of the energy levels.

Ashwagandha (Withania somnifera) and Shunthi (Zingiber officinale) in mild and moderate COVID-19: An open-label randomized controlled exploratory trial.

BACKGROUND: Ayurveda interventions have been used for prophylaxis and care during the COVID-19 pandemic in India and have shown promising results in promoting early clinical recovery from COVID-19. OBJECTIVE: To assess the efficacy and safety of Ashwagandha [Withania somnifera (L.) Dunal] tablet and Shunthi (Zingiber officinale Roscoe) capsule in mild and moderate COVID-19 compared to conventional standard care. METHODS: A randomized controlled exploratory trial was conducted at a designated COVID-19 care center in India with 60 participants having mild or moderate COVID-19. Ashwagandha, two tablets (250 mg each), and Shunthi, two capsules (500 mg each) twice daily for 15 days, were given orally to the participants in the Ayurveda group (AG) and the control group (CG) received conventional standard care. The outcome measures included clinical recovery rate, the proportion of participants with negative RT-PCR assay for COVID-19 on day 7 and day 15, mean time to attain clinical recovery, change in pro-inflammatory markers, serum IgG for COVID-19, HRCT chest findings, disease progression and incidence of adverse events (AE). RESULTS: A total of 60 participants were enrolled, and the data of 48 participants (AG = 25 and CG = 23) were considered for the statistical analysis. The mean time for clinical recovery was reduced by almost 50 % in the AG (6.9 days) compared to CG (13.0 days) (p < 0.001). The proportion of participants who attained viral clearance in AG was 76.0 % compared to 60.8 % in the CG (RR= 1.24, 95 % CI: 0.841, 1.851, p-value = 0.270). Changes in the pro-inflammatory markers, serum IgG for COVID-19, and HRCT chest findings were comparable in both groups, and no AE or disease progression was reported. CONCLUSIONS: The Ayurveda interventions, Ashwagandha and Shunthi, can effectively reduce the duration of clinical recovery and improve time for viral clearance in mild and moderate COVID-19. These interventions were observed to be safe and well-tolerated during the duration of the trial. TRIAL REGISTRATION: Clinical Trial Registry of India - CTRI/2020/08/027224.

AYUSH-64 as an adjunct to standard care in mild to moderate COVID-19: An open-label randomized controlled trial in Chandigarh, India.

OBJECTIVE: To determine the therapeutic efficacy and safety of AYUSH-64 as an add-on to standard care in mild to moderate COVID-19. DESIGN SETTING, AND INTERVENTIONS: This open-label randomized controlled parallel-group trial was conducted at a designated COVID care centre in India in 80 patients diagnosed with mild to moderate COVID-19 and randomized into two groups. Participants in the AYUSH-64 add-on group (AG) received AYUSH-64 two tablets (500 mg each) three times a day for 30 days along with standard conventional care. The control group (CG) received standard care alone. MAIN OUTCOME MEASURES: Proportion of participants who attained clinical recovery on day 7, 15, 23 and 30, proportion of participants with negative RT-PCR assay for COVID-19 at each weekly time point, change in pro-inflammatory markers, metabolic functions, HRCT chest (CO-RADS category) and incidence of Adverse Drug Reaction (ADR)/Adverse Event (AE). RESULTS: Out of 80 participants, 74 (37 in each group) contributed to the final analysis. Significant difference was observed in clinical recovery in the AG (p < 0.001 ) compared to CG. Mean duration for clinical recovery in AG (5.8 ± 2.67 days) was significantly less compared to CG (10.0 ± 4.06 days). Significant improvement in HRCT chest was observed in AG (p = 0.031) unlike in CG (p = 0.210). No ADR/SAE was observed or reported in AG. CONCLUSIONS: AYUSH-64 as adjunct to standard care is safe and effective in hastening clinical recovery in mild to moderate COVID-19. The efficacy may be further validated by larger multi-center double-blind trials.

Trinuclear {Co(2+)-M(3+)-Co(2+)} complexes catalyze reduction of nitro compounds.

This work presents synthesis and characterization of trinuclear {Co(2+)-Co(3+)-Co(2+)} and {Co(2+)-Fe(3+)-Co(2+)} complexes with accessible peripheral Co(ii) ions. Both trinuclear complexes function as efficient reusable heterogeneous catalysts for the selective reduction of assorted nitro compounds to the corresponding amines. The mechanistic investigations suggest the involvement of a Co(ii)-Co(i) cycle in the catalysis.