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.

[Central mechanism of acupuncture intervention in anxiety and depression under fMRI].

Despite the significant efficacy of acupuncture in alleviating anxiety and depression, the mechanism remains unclear. In recent years, functional magnetic resonance imaging (fMRI) technology has provided a visual method for deciphering the mechanism of acupuncture in treating anxiety and depression. This paper summarized the clinical studies about the imaging changes of anxiety and depression during the treatment with acupuncture under fMRI. The available studies demonstrated that acupuncture may act on functional nuclei and brain regions such as hippocampus, amygdala, cingulate gyrus, frontal lobe, and temporal lobe. The paper can lay a foundation for the further study of the central mechanism of acupuncture in the treatment of anxiety and depression.

Demethylbellidifolin prevents nitroglycerin tolerance via improved aldehyde dehydrogenase 2 activity.

The aim of this study was to investigate the effect of demethylbellidifolin (DMB), a major xanthone compound of Swertia davidi franch, on nitroglycerin (NTG) tolerance. In the in vivo portion of the study, pretreatment of Sprague-Dawley rats with NTG (10 mg/kg) for 8 days caused tolerance to the depressor effect of NTG. This was evident because the depressor effect of NTG (150 microg/kg, I. V.) was almost completely abolished in the tolerant rats. The tolerance could be diminished by treatment with DMB. In the in vitro study, the exposure of aortic rings of Sprague-Dawley rats to NTG (10 microM) for 30 min caused tolerance to the vasodilating effect of NTG. The tolerance is evident because of a substantial right shift of the NTG concentration-relaxation curves. This shift was reduced by pretreatment of the aortic rings with DMB. In cultured human umbilical vein endothelial cells (HUVECs), incubation of NTG for 16 h increased reactive oxygen species (ROS) production, attenuated cyclic guanosine monophosphate (cGMP) levels and decreased the activity of aldehyde dehydrogenase 2 (ALDH-2), the main enzyme responsible for NTG bioactivation. All the effects mentioned above were prevented by co-incubation with DMB. In conclusion, DMB prevents NTG tolerance via increasing ALDH-2 activity through decreasing ROS production.

Involvement of the endothelial DDAH/ADMA pathway in nitroglycerin tolerance: the role of ALDH-2.

Previous studies have shown that nitroglycerin (GTN) tolerance is closely related to an oxidative stress-induced decrease in activity of mitochondrial isoforms of aldehyde dehydrogenase (ALDH-2), and prolonged GTN treatment causes endothelial dysfunction. Asymmetric dimethylarginine (ADMA), a major endogenous NO synthase (NOS) inhibitor, could inhibit NO production and induce oxidative stress in endothelial cells. ADMA and its major hydrolase dimethylarginine dimethylaminohydrolase (DDAH) have recently been thought of as a novel regulatory system of endothelium function. The aim of the present study was to determine whether the DDAH/ADMA pathway is involved in the development of GTN tolerance in endothelial cells. Tolerance, reflected by the decrease in cyclic GMP (cGMP) production, was induced by exposure of human umbilical vein endothelial cells (HUVECs) to GTN (10 microM) for 16 h. While the treatment increased reactive oxygen species (ROS) production/malondialdehyde (MDA) concentration and decreased ALDH-2 activity as well as cGMP production, it markedly increased the level of ADMA in culture medium and decreased DDAH activity in endothelial cells. Exogenous ADMA significantly enhanced ROS production/MDA concentration and inhibited ALDH-2 activity, and overexpression of DDAH2 could significantly suppress GTN-induced oxidative stress and inhibition of ALDH-2 activity, which is also attenuated by L-arginine. Therefore, our results suggest for the first time that the endothelial DDAH/ADMA pathway plays an important role in the development/maintenance of GTN tolerance.

Reversal of tolerance to nitroglycerin with vinpocetine: a role of calcitonin gene-related peptide.

Previous studies have shown that the development of tolerance to nitroglycerin is related to reduction of endogenous calcitonin gene-related peptide (CGRP) release. In the present study, Nitroglycerin caused a concentration-dependent relaxation concomitantly with a significant increase in the release of CGRP in the isolated rat thoracic aorta, an effect that was reduced by preincubation with capsaicin. Pretreatment with nitroglycerin significantly decreased its vasodilation and depressor effect and the release of CGRP, which was restored in the presence of vinpocetine, an inhibitor of phosphodiesterase. The present results suggest that reversal of tolerance to nitroglycerin with vinpocetine is related to the increased release of CGRP in the rat.

Decrease in endogenous CGRP release in nitroglycerin tolerance: role of ALDH-2.

In the present study, we tested whether the decreased release of calcitonin gene-related peptide (CGRP) observed in nitroglycerin tolerance is associated with the decrease in aldehyde dehydrogenase (ALDH-2) activity. We further investigated the possible involvement of reactive oxygen species in the decrease in ALDH-2 activity. Tolerance was induced by exposure of isolated rat thoracic aortas and human umbical vein endothelial cells (HUVEC) to nitroglycerin in vitro or by pretreatment with nitroglycerin for 8 days in vivo. Pretreatment with ALDH-2 inhibitors and nitroglycerin significantly attenuated vasodilator responses to nitroglycerin concomitantly with a decrease in the release of CGRP from the isolated thoracic aorta. Nitroglycerin produced a depressor effect concomitantly with an increase in plasma concentrations of CGRP, and the effect of nitroglycerin was attenuated after pretreatment with an inhibitor of ALDH-2 or nitroglycerin for 8 days. Exposure of HUVEC to nitroglycerin for 16 h increased reactive oxygen species production and decreased ALDH-2 activity as well as cGMP production in a time-and concentration-dependent manner. Pretreatment with an ALDH-2 inhibitor also significantly decreased the cGMP production. However, tolerance to nitroglycerin in HUVEC was restored in the presence of N-acetylcysteine or captopril. The present results suggest that nitrate tolerance is, at least partially, associated with a decrease in endogenous CGRP release via a decrease in ALDH-2 activity as a result of stimulation of reactive oxygen species production.

Osteoporosis: prevalence in Taiwanese women.

The aim of this study is to understand the current status of bone mineral density (BMD) among Taiwanese women and to determine the relationship between bone mass, weight, height and body mass index (BMI), and the proportion of osteoporosis sufferers, based on World Health Organization standards, in each age group. A total of 4689 women underwent lumbar vertebrae (L2-L4) BMD measurements, and 3529 women underwent femoral neck bone mineral density measurements. BMD was measured using dual-energy X-ray absorptiometry. Standards were based on the BMD of the 20- to 40-year-old age group, as were relationships between height, weight, BMI, and BMD. Pearson correlation revealed a positive relationship between body weight, BMI, and BMD in the femoral neck; other correlations were insignificant. The defined BMD value for a diagnosis of osteoporosis was 0.827 g/cm(2) for lumbar vertebrae and 0.605 g/cm(2) for the femoral neck. The proportion of osteoporosis calculated for each age group in the lumbar vertebrae group was: 40-49 years old, 8.25%; 50-59 years old, 8.62%; 60-69 years old, 14.14%; 70-79 years old, 14.25%; >80 years old, 16.07%. For the femoral neck group, the values were: 40-49 years old, 5.24%; 50-59 years old, 5.28%; 60-69 years old, 11.17%; 70-79 years old, 17.30%; >80 years old, 24%. The total proportion of osteoporosis in the lumbar vertebrae was 10.08%, and in the femoral neck, 7.45%. The BMD of Taiwanese women shows a positive relationship to body weight and BMI in the femoral neck group but not in the lumbar vertebrae group. The proportion of osteoporosis by age group in this cohort was lower than that among Western women.