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Background : Extending the dosing interval of a primary series of mRNA COVID-19 vaccination has been employed to reduce myocarditis risk in adolescents, but previous evaluation of impact on vaccine effectiveness (VE) is limited to risk after second dose. Methods: We quantified the impact of the dosing interval based on case notifications and vaccination uptake in Hong Kong from January to April 2022, based on calendar-time proportional hazards models and matching approaches. Results: We estimated that the hazard ratio (HR) and odds ratio (OR) of infections after the second dose for extended (28 days or more) versus regular (21–27 days) dosing intervals ranged from 0.86 to 0.99 from calendar-time proportional hazards models, and from 0.85 to 0.87 from matching approaches, respectively. Adolescents in the extended dosing groups (including those who did not receive a second dose in the study period) had a higher hazard of infection than those with a regular dosing interval during the intra-dose period (HR 1.66; 95% CI 1.07, 2.59; p = 0.02) after the first dose. Conclusions: Implementing an extended dosing interval should consider multiple factors including the degree of myocarditis risk, the degree of protection afforded by each dose, and the extra protection achievable using an extended dosing interval. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress and the resulting inflammation are essential pathological processes in acute lung injury (ALI). Nuclear factor erythroid 2-related factor 2 (Nrf2), a vital transcriptional factor, possesses antioxidative potential and has become a primary target to treat many diseases. Oridonin (Ori), isolated from the plant Rabdosia Rrubescens, is a natural substance that possesses antioxidative and anti-inflammatory effects. Our aim was to study whether the anti-inflammatory and antioxidant effects of Ori on LPS-induced ALI were mediated by Nrf2. Methods: MTT assays, Western blotting analysis, a mouse model, and hematoxylin-eosin (H & E) staining were employed to explore the mechanisms by which Ori exerts a protective effect on LPS-induced lung injury in RAW264.7 cells and in a mouse model. Results: Our results indicated that Ori increased the expression of Nrf2 and its downstream genes (HO-1, GCLM), which was mediated by the activation of Akt and MAPK. Additionally, Ori inhibited LPS-induced activation of the pro-inflammatory pathways NLRP3 inflammasome and NF-κB pathways. These two pathways were also proven to be Nrf2-independent by the use of a Nrf2 inhibitor. In keeping with these findings, Ori alleviated LPS-induced histopathological changes, the enhanced production of myeloperoxidase and malondialdehyde, and the depleted expression of GSH and superoxide dismutase in the lung tissue of mice. Furthermore, the expression of LPS-induced NLRP3 inflammasome and NF-κB pathways was more evident in Nrf2-deficient mice but could still be reversed by Ori. Conclusions: Our results demonstrated that Ori exerted protective effects on LPS-induced ALI via Nrf2-independent anti-inflammatory and Nrf2-dependent antioxidative activities. [ABSTRACT FROM AUTHOR]

Background: The new HIV treatment guidelines in China recommend antiretroviral therapy (ART) for all people living with HIV, but significant gaps in implementation still exist. Pre-exposure prophylaxis (PrEP) can effectively reduce the risk of HIV transmission among men who have sex with men (MSM). This study assessed the epidemiological impact and cost effectiveness of PrEP, enhanced biomedical interventions and their combination among MSM in China.Methods: A deterministic mathematical model was developed and projected over 20 years to assess the impact of the PrEP, biomedical interventions and their combinations. Incidence and prevalence of HIV were measured, and cost-effectiveness was assessed using incremental cost (international dollars, Int.$) per quality-adjusted life year (QALY) gained.Results: A total of 0.78 million new HIV infections were estimated to occur over the next 20 years if no additional interventions are implemented among MSM. The PrEP-only strategy covering 25-75% of HIV-negative high-risk MSM can prevent 0.09-0.20 million (12.1-25.7%) new infections, at a cost of 17,277-18,452 Int.$/QALY. The optimal cost-effectiveness path is from test-and-treat to the combination strategy of test-and-treat and PrEP. Some strategies could almost eliminate new HIV infections over the next 20 years.Conclusions: PrEP, test-and-treat, and their combinations among MSM are effective and cost-effective relative to current policy. PrEP is an important and cost-effective addition to current policy in China. [ABSTRACT FROM AUTHOR]