Specific role of NAD+ biosynthesis reduction mediated mitochondrial dysfunction in vascular endothelial injury induced by chronic intermittent hypoxia.

OBJECTIVE: Cardiovascular diseases (CVD) are prevalent among those with obstructive sleep apnea (OSA) and are the leading cause of death in these individuals. However, due to clinical confounders, the mechanism by which OSA induces CVD is still unclear. Previous studies have shown that chronic intermittent hypoxia (CIH) and high cholesterol diet (HCD) induce distinct characteristics of atherosclerotic plaques, highlighting the specific mechanisms involved in CIH-induced vascular endothelial injury. MATERIALS AND METHODS: This study aims to investigate whether nicotinamide adenine dinucleotide (NAD+) biosynthesis reduction-mediated mitochondrial dysfunction is responsible for vascular endothelial injury induced by CIH and to elucidate its specific role in this process. Models were established to stimulate human umbilical vein endothelial cells (HUVECs) with CIH and oxidized low-density lipoprotein (ox-LDL), and the NAD+ biosynthesis-related indicators, such as NAD+ levels and nicotinamide phosphoribosyltransferase (NAMPT) enzyme activity, were measured in this model. Additionally, interventions were performed by supplementing NAD+ levels with nicotinamide mononucleotide (NMN), inhibiting NAD+ synthesis with FK866, and evaluating mitochondrial function, oxidative stress status, vascular constriction and dilation function, and endothelial adhesion function in these models. A comparative study was conducted to assess the effects of these interventions. RESULTS: We found that under CIH conditions, NAMPT enzyme activity was inhibited, leading to a reduction in NAD+ biosynthesis and a decrease in NAD+/NADH ratio. At the same time, CIH caused mitochondrial dysfunction in HUVECs, including a decrease in adenosine triphosphate (ATP) content and mitochondrial membrane potential, as well as the activity of respiratory chain complex I and III, induced an increase in oxidative stress levels in endothelial cells, impaired vascular constriction and dilation function, and significantly increased expression of adhesion factors. The impact of CIH on endothelial cell-related mitochondrial function and endothelial function was restored by supplementing NMN. Although ox-LDL also causes multi-level endothelial injury, it does not involve the NAD+ pathway, as there were no significant changes in the related indicators, and the impaired endothelial function under ox-LDL conditions was not restored by supplementing NMN. CONCLUSIONS: CIH-induced vascular endothelial injury may be associated with NAD+ biosynthesis reduction-mediated mitochondrial dysfunction. Supplementing NAD+ precursors to increase its levels may be a potential intervention to ameliorate CIH-induced vascular endothelial injury, while it does not have a significant effect on endothelial injury caused by ox-LDL.

Prevalence and risk factors of otitis media with effusion in children with obstructive sleep apnea.

OBJECTIVE: The aim of this study was to investigate the correlation between obstructive sleep apnea (OSA) and otitis media with effusion (OME) in Chinese children and identify risk factors for OME to support the development of standardized diagnostic and treatment methods. PATIENTS AND METHODS: Clinical data of 1,021 children with OSA admitted to our hospital between January 2019 and December 2020 were collected. The prevalence of OME was assessed based on age groups and different grades of adenoid hypertrophy (AH). Multivariate logistic regression was performed to determine risk factors for OME in this population. RESULTS: Among the patients, only 73 (6.15%) reported hearing loss as the main complaint, while 178 (17.43%) were diagnosed with OME after the examination. Acoustic immittance showed higher detection rates for OME compared to those of otoscopy and pure tone audiometry. In addition, the incidence of OME did not increase with AH grade but was higher in children with OSA with AH grade IV. Multivariate regression analysis showed that the younger age group (2-5 years), AH grade IV, nasal inflammatory disease, and passive smoking were significant risk factors for OSA and OME. However, sex, age of 6-12 years, and presence of chronic tonsillitis/tonsillar hypertrophy had no significant impact on the prevalence of OME. CONCLUSIONS: OME is highly prevalent in children with OSA. Clinicians should be vigilant in diagnosing OME, should conduct routine audiological examinations, and actively screen for middle ear fluid in all children with OSA, especially in younger children (2-5 years) with nasal mucosa inflammation and a history of passive smoking. This will help improve the detection rate of OME, as early intervention is paramount for preventing complications.

[Well-differentiated liposarcoma of the retropharyngeal space: a case report].

Liposarcomas represent a significant proportion of softtissue sarcomas. However, rare cases of primary liposarcoma of the throat have been reported in the literature and they are exceedingly rare in the retropharyngeal space. The present study report a case of a 60 year old patient with retropharyngeal liposarcoma. Uniquely, because the patient has a hashimoto's thyroiditis, therefore the patient presented with typically worsening poor breathing.

[Cervical pharyngeal syndrome: a case report].

Summary Cervical pharyngeal syndrome is characterized by the symptom such as sore throat, foreign body sensation or swallowing discomfort which caused by the pathological changes of cervical intervertebral disc and intervertebral structure nonspecific injury. Because of the lack of obvious specificity, it is easy to misdiagnose. Here, we reported a case of cervical pharyngeal syndrome. The symptom were obviously improved after conservative treatment, but the follow-up time is short, and further follow-up is needed. In the process of diagnosis and treatment, in order to reduce misdiagnosis and mistreatment, we should strengthen the understanding of the disease, broaden the clinical thinking, and understand the anatomical relationship between the pharynx and the surrounding organs.

Pregnancy outcome in gestational diabetes.

OBJECTIVE: To assess maternal and neonatal outcomes of gestational diabetes mellitus (GDM) following glycemic screening and diabetic management, with special focus on concurrent GDM and pre-eclampsia. METHODS: A retrospective chart review of 782 women diagnosed with and treated for GDM at a Chinese university teaching hospital. Data on maternal and neonatal outcome, glycemic control, concurrent pre-eclampsia, and diabetic management were collected and analyzed. RESULTS: The incidence of GDM was 3.8%. Of the affected women, 62.9% were managed with diet only and the remainder received insulin treatment. Overall, 80.7% had good glycemic control. Poor glycemic control and concurrent pre-eclampsia correlated with maternal and neonatal complications. CONCLUSION: Aggressive management for tight glycemic control improves maternal and neonatal outcomes in women with GDM.