Global, regional, and national prevalence of hearing loss from 1990 to 2019: A trend and health inequality analyses based on the Global Burden of Disease Study 2019.

As a severe public health issue, hearing loss has caused an increasingly disease burden, especially in the elderly population. Hearing loss may inevitably induce asymmetric hearing, which makes it difficult for elderly individuals to locate sound sources, therefore resulting in increased postural instability and falling risk. To emphasize the public health emergence of hearing loss, we investigated the temporal trend of prevalence of hearing loss over the last 30 years and further predicted its changes in the next 20 years, decomposed the trend according to demographic factors and epidemiological changes, and quantified the cross-country healthy inequalities, using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. In 2019, there were more than 140 million cases of hearing loss worldwide, a 93.89% increase from 70 million cases in 1990. The age-standardized rate (ASR) also increased with an estimated annual percentage change of 0.08% per year. Population growth and aging are the major drivers contributing to the changes, accounting for 60.83% and 35.35%. Of note, the contribution of aging varies showing a gradual increasing trend with sociodemographic index (SDI) elevating. Also notable, there were significant health inequalities across 204 countries and territories, with slope index of inequality rising over time. Projection of the global burden of hearing loss from 2020 to 2040 indicated progressive increases in both case number and ASR. These reflect the heavy disease burden of hearing loss that needed more targeted and efficient strategies in its prevention and management.

Biodegradable hydrogels with photodynamic antibacterial activity promote wound healing and mitigate scar formation.

Bacterial proliferation and the disordered extracellular matrix (ECM) at the wound site are the major reasons for delayed healing and abnormal scarring. The development of new multifunctional dressing materials that can effectively prevent scar formation without delaying wound healing remains a challenge. In this study, we construct a verteporfin-loaded biodegradable hydrogel (VP-gel) using hyaluronic acid and thiol-terminated 4-arm polyethylene glycol (PEG). The injectable VP-gel sustainably releases small doses of verteporfin in the wound microenvironment that generates reactive oxygen species (ROS) under red light irradiation to kill bacteria efficiently. Importantly, the sustained release of VP could also regulate TGF-ß family-induced cellular responses and the downstream signaling molecule Smad2 in fibroblasts to reduce myofibroblast differentiation, promoting ECM reconstruction and scarless wound healing. Immunohistochemical examination of wound healing and histomorphology in a mouse full-thickness wound model demonstrates excellent acceleration effects of VP-gel for infected wound healing. Therefore, VP-gel with anti-scarring and antibacterial activity, as well as enhanced infection wound healing ability shows great potential in the clinical treatment of scar healing for infected wounds.