Trust performance in managing inflammatory arthritis over time in England and Wales: a latent class analysis approach.

Objectives: To evaluate trust-level performance in time to initiation of DMARD therapy in patients with early inflammatory arthritis (EIA), with identification of the change in performance trajectories over time and investigation of trust characteristics associated with this change. Methods: We included 130 trusts from the UK contributing to the National Early Inflammatory Arthritis Audit (NEIAA) from 2018 to 2020. The primary outcome was days from referral to initiation of DMARD therapy in patients with EIA. Latent class growth mixture models were applied to identify distinct groups of trusts with similar trajectories of performance change over time. We used mixed effects linear and multinomial logistic regression models to evaluate the association between delay in treatment and trust-level characteristics. Results: The mean time to DMARD initiation was 53 days (s.d. 18), with an average 0.3-day decrease with each month over time. Four latent trajectories were identified in our cohort, with >77% of individual trusts showing ongoing improvements in decreasing treatment waiting times. Prior to separating by latent class, time to DMARD initiation was shorter in trusts with higher rheumatology staffing, a local EIA treatment pathway and those with access to musculoskeletal ultrasound. Trusts with more nurses in the rheumatology department were less likely to be in the worst performance group [odds ratio 0.69 (95% CI 0.49, 0.93)]. Conclusion: In this cohort study, we observed a reduction in treatment waiting time over time. Trusts with better staffed and improved EIA clinical structure are likely to initiate definitive treatment earlier in patients with EIA.

ROS-induced oxidative stress and mitochondrial dysfunction: a possible mechanism responsible for noise-induced ribbon synaptic damage.

Evidence suggests that damage to the ribbon synapses (RS) may be the main cause of auditory dysfunction in noise-induced hearing loss (NIHL). Oxidative stress is implicated in the pathophysiology of synaptic damage. However, the relationship between oxidative stress and RS damage in NIHL remains unclear. To investigate the hypothesis that noise-induced oxidative stress is a key factor in synaptic damage within the inner ear, we conducted a study using mice subjected to single or repeated noise exposure (NE). We assessed auditory function using auditory brainstem response (ABR) test and examined cochlear morphology by immunofluorescence staining. The results showed that mice that experienced a single NE exhibited a threshold shift and recovered within two weeks. The ABR wave I latencies were prolonged, and the amplitudes decreased, suggesting RS dysfunction. These changes were also demonstrated by the loss of RS as evidenced by immunofluorescence staining. However, we observed threshold shifts that did not return to baseline levels following secondary NE. Additionally, ABR wave I latencies and amplitudes exhibited notable changes. Immunofluorescence staining indicated not only severe damage to RS but also loss of outer hair cells. We also noted decreased T-AOC, ATP, and mitochondrial membrane potential levels, alongside increased hydrogen peroxide concentrations post-NE. Furthermore, the expression levels of 4-HNE and 8-OHdG in the cochlea were notably elevated. Collectively, our findings suggest that the production of reactive oxygen species leads to oxidative damage in the cochlea. This mitochondrial dysfunction consequently contributes to the loss of RS, precipitating an early onset of NIHL.

Horizontal ridge augmentation in the maxillary aesthetic region using the autogenous circular cortical-lamina anchoring technique: A case series study.

AIM: This case series aimed to evaluate the effectiveness of the autologous circular cortical lamina-anchoring (CCA) technique for horizontal bone augmentation in the maxillary aesthetic region. MATERIALS AND METHODS: A total of 25 patients with 28 implants underwent horizontal bone augmentation using CCA followed by implant placement and crown delivery. The primary outcome measures were alveolar ridge width (ARW) and buccal bone thickness (BBT), whereas the secondary outcome measures included marginal bone loss (MBL), mid-facial mucosal margin loss (MML), clinical assessment of peri-implant and aesthetic parameters, patient-reported outcome measures (PROMs), and implant survival rates. RESULTS: All 25 patients with 28 implants completed the treatment, no dropouts occurred. After CCA, the mean ARW at 1, 2, and 4 mm below the alveolar crest significantly increased from 2.38 ± 0.48, 2.85 ± 0.51, and 3.21 ± 0.53 mm to 6.80 ± 0.48, 6.99 ± 0.50, and 8.08 ± 0.52 mm, respectively. At the 3-year follow-up, the mean BBT0 , BBT2 , and BBT4 slightly decreased from 2.51 ± 0.26, 2.63 ± 0.31, and 2.75 ± 0.29 mm to 2.43 ± 0.27, 2.51 ± 0.30, and 2.64 ± 0.28 mm, respectively. Although the overall MBL was <0.15 mm, the results were statistically significant. The mean MML at the 3-year follow-up was 0.02 mm. All implant sites showed acceptable peri-implant and aesthetic outcomes. Incisions healed without complications, and no significant differences in PROMs observed at any time point. The 3-year follow-up showed a 100% implant survival rate. CONCLUSION: The autologous CCA technique is a useful method for increasing ARW and maintaining BBT in the maxillary aesthetic region.

Genetic determinants of IgG antibody response to COVID-19 vaccination.

Human humoral immune responses to SARS-CoV-2 vaccines exhibit substantial inter-individual variability and have been linked to vaccine efficacy. To elucidate the underlying mechanism behind this variability, we conducted a genome-wide association study (GWAS) on the anti-spike IgG serostatus of UK Biobank participants who were previously uninfected by SARS-CoV-2 and had received either the first dose (n = 54,066) or the second dose (n = 46,232) of COVID-19 vaccines. Our analysis revealed significant genome-wide associations between the IgG antibody serostatus following the initial vaccine and human leukocyte antigen (HLA) class II alleles. Specifically, the HLA-DRB1∗13:02 allele (MAF = 4.0%, OR = 0.75, p = 2.34e-16) demonstrated the most statistically significant protective effect against IgG seronegativity. This protective effect was driven by an alteration from arginine (Arg) to glutamic acid (Glu) at position 71 on HLA-DRß1 (p = 1.88e-25), leading to a change in the electrostatic potential of pocket 4 of the peptide binding groove. Notably, the impact of HLA alleles on IgG responses was cell type specific, and we observed a shared genetic predisposition between IgG status and susceptibility/severity of COVID-19. These results were replicated within independent cohorts where IgG serostatus was assayed by two different antibody serology tests. Our findings provide insights into the biological mechanism underlying individual variation in responses to COVID-19 vaccines and highlight the need to consider the influence of constitutive genetics when designing vaccination strategies for optimizing protection and control of infectious disease across diverse populations.

No Waning of Pneumococcal Vaccine Responses over Time in People with Inflammatory Arthritis: Findings from a Single Centre Cohort.

BACKGROUND: Vaccination against pneumococcus reduces the risk of infective events, hospitalisation, and death in individual with inflammatory arthritis, particularly in those on immunomodulating therapy who are at risk of worse outcomes from pneumococcal disease. The objective of this study was to investigate the serological protection following vaccination against pneumococcal serovars over time. Methods: This was a single centre, retrospective cohort study of individuals with rheumatoid arthritis, psoriatic arthritis, or axial spondylarthritis who had previously received the PPSV23 polysaccharide pneumococcal vaccine (Pneumovax). Data were retrieved between January 2021 to August 2023. Dates of previous pneumococcal vaccination were identified using linked primary care records. Serum serotype levels were collected. The primary outcome was serological response defined as a titre ≥0.35 mcg/mL in at least five from a total of 12 evaluated pneumococcal serovars, examined using a Luminex platform. Multivariate logistic regression models adjusting for age, gender, ethnicity, co-morbidities, and the use of prednisolone, conventional synthetic and biological DMARDs were used to determine the odds of a sustained serological response according to time categorised into ≤5 years, 5-10 years, and ≥10 years since vaccination. Results: Serological response was measured in 296 individuals with inflammatory arthritis, with rheumatoid arthritis the most common diagnosis (74% of patients). The median time between pneumococcal vaccine administration and serological assessment was 6 years (interquartile range 2.4 to 9.9). A positive serological response to at least 5 serovars was present in 195/296 (66%) of patients. Time since vaccination did not significantly associate with serological protection compared with those vaccinated <5 years, the adjusted ORs of vaccine response was 1.15 (95% CI 0.64 to 2.07) in those 5-10 years and 1.26 (95% CI: 0.64 to 2.48) in those vaccinated over 10 years ago. No individual variable from the multivariate model reached statistical significance as an independent predictor of vaccine response, although steroid use at the time of vaccine had a consistent detrimental impact on serological immunity. Conclusions: We demonstrated that antibody titres following vaccination against pneumococcal serovars do not appear to wane over time. It appears more critical to focus on maximising the initial vaccine response, which is known to be diminished in this patient population.

Genetic basis of pregnancy-associated decreased platelet counts and gestational thrombocytopenia.

ABSTRACT: Platelet count reduction occurs throughout pregnancy, with 5% to 12% of pregnant women being diagnosed with gestational thrombocytopenia (GT), characterized by a more marked decrease in platelet count during pregnancy. However, the underlying biological mechanism behind these phenomena remains unclear. Here, we used sequencing data from noninvasive prenatal testing of 100 186 Chinese pregnant individuals and conducted, to our knowledge, the hitherto largest-scale genome-wide association studies on platelet counts during 5 periods of pregnancy (the first, second, and third trimesters, delivery, and the postpartum period) as well as 2 GT statuses (GT platelet count < 150 × 109/L and severe GT platelet count < 100 × 109/L). Our analysis revealed 138 genome-wide significant loci, explaining 10.4% to 12.1% of the observed variation. Interestingly, we identified previously unknown changes in genetic effects on platelet counts during pregnancy for variants present in PEAR1 and CBL, with PEAR1 variants specifically associated with a faster decline in platelet counts. Furthermore, we found that variants present in PEAR1 and TUBB1 increased susceptibility to GT and severe GT. Our study provides insight into the genetic basis of platelet counts and GT in pregnancy, highlighting the critical role of PEAR1 in decreasing platelet counts during pregnancy and the occurrence of GT. Those with pregnancies carrying specific variants associated with declining platelet counts may experience a more pronounced decrease, thereby elevating the risk of GT. These findings lay the groundwork for further investigation into the biological mechanisms and causal implications of GT.

Incidence of Uveitis in Patients With Axial Spondylarthritis Treated With Biologics or Targeted Synthetics: A Systematic Review and Network Meta-Analysis.

OBJECTIVE: Anterior uveitis is a common extra-articular manifestation of axial spondyloarthritis (AxSpA). We set to evaluate the risk of anterior uveitis (AU) with biologics and synthetic disease-modifying drugs in AxSpA. METHODS: We conducted a systematic review and meta-analysis to identify phase II/III double-blinded randomized controlled trials of anti-tumor necrosis factor (TNF) monoclonal antibodies (mAb), anti-interleukin-17 (anti-IL-17), and Janus kinase inhibitors (JAKi) in AxSpA. Patient-exposure years (PEY) were calculated using the per-protocol approach. Incidence rate (IR) of AU/100 person-years were calculated by treatment group using the random effects approach. Network meta-analysis (NMA) was used to estimate risk of AU in treatment groups, expressed as IR ratios (IRRs). Bias was assessed using the Cochrane Risk of Bias-2 tool. RESULTS: Forty-four trials were included: 17 anti-TNF mAb (1,004 PEY), 9 etanercept (180 PEY), 13 anti-IL-17 (1,834 PEY), and 6 JAKi (331 PEY). The IR of AU were as follows for anti-TNF mAb: 4.1, 95% confidence interval (CI) 0-8.5; etanercept: 5.4, 95% CI 0-16.0; anti-IL-17: 2.8, 95% CI 1.6-4.1; JAKi: 1.5, 95% CI 0.0-3.0; and placebo: 10.8, 95% CI 7.4-14.1. In NMA, IRRs of treatments compared with placebo were as follows for anti-TNF mAb: 0.32, 95% CI 0.10-1.04; etanercept 0.42, 95% CI 0.08-2.38; anti-IL-17: 0.43, 95% CI 0.19-0.98; and JAKi: 0.32, 95% CI 0.06-1.67. Comparisons between anti-TNF mAb, anti-IL-17, and JAKi did not demonstrate any significant difference in AU risk. Using the surface under the cumulative ranking curve approach to rank AU risk, anti-TNF mAbs were associated with the lowest risk followed by JAKi, anti-IL-17, and etanercept. All treatments were ranked superior to placebo. CONCLUSION: Anti-TNF mAbs, JAKi, and anti-IL-17 appear protective against AU events in individuals with AxSpA, with no significant differences in risk of AU between treatments.

A Systematic Review and Meta-Analysis of Anti-Rheumatic Drugs and Pneumococcal Vaccine Immunogenicity in Inflammatory Arthritis.

BACKGROUND: Pneumococcal pneumonia is an important cause of morbidity and mortality amongst patients with inflammatory arthritis. Vaccination is recommended by the National Institute for Health and Care Excellence (NICE) but it remains unclear how vaccine efficacy is impacted by different immunosuppressive agents. Our objective was to compare the chance of a seroconversion following vaccination against pneumococcus in patients with inflammatory arthritis to that in the general population, as well as to compare the chance of seroconversion across different targeted therapies. METHODS: We searched MEDLINE, Embase and the Cochrane Library databases from inception until 20 June 2023. We included randomized controlled trials and observational studies. Aggregate data were used to undertake a pairwise meta-analysis. Our primary outcome of interest was vaccine seroconversion. We accepted the definition of serological response reported by the authors of each study. RESULTS: Twenty studies were identified in the systematic review (2807 patients) with ten reporting sufficient data to be included in the meta-analysis (1443 patients). The chance of seroconversion in patients receiving targeted therapies, relative to the general population, was 0.61 (95% CI 0.35 to 1.08). The reduced odds of response were skewed strongly by the effects of abatacept and rituximab with no difference between patients on TNF inhibitors (TNFis) or IL-6 inhibition and healthy controls. Within different inflammatory arthritis populations the findings remained consistent, with rituximab having the strongest negative impact on vaccine response. TNF inhibition monotherapy was associated with a greater chance of vaccine response compared with methotrexate (2.25 (95% CI 1.28 to 3.96)). JAK inhibitor (JAKi) studies were few in number and did not present comparable vaccine response endpoints to include in the meta-analysis. The information available does not suggest any significant detrimental effects of JAKi on vaccine response. CONCLUSION: This updated meta-analysis confirms that, for most patients with inflammatory arthritis, pneumococcal vaccine can be administered with confidence and that it will achieve comparable seroconversion rates to the healthy population. Patients on rituximab were the group least likely to achieve a response and further research is needed to explore the value of multiple-course pneumococcal vaccination schedules in this population.

D-galactose-induced mitochondrial oxidative damage and apoptosis in the cochlear stria vascularis of mice.

BACKGROUND: Age-related hearing loss, known as presbycusis, is the result of auditory system degeneration. Numerous studies have suggested that reactive oxygen species (ROS) and mitochondrial oxidative damage play important roles in the occurrence and progression of aging. The D-galactose (D-gal)-induced aging model is well known and widely utilized in aging research. Our previous studies demonstrate that administration of D-gal causes mitochondrial oxidative damage and causes subsequent dysfunction in the cochlear ribbon synapses, which in turn leads to hearing changes and early stage presbycusis. Stria vascularis (SV) cells are vital for hearing function. However, it is unclear to what extent D-gal induces oxidative damage and apoptosis in the cochlear SV of mice. In addition, the source of the causative ROS in the cochlear SV has not been fully investigated. METHODS: In this study, we investigated ROS generation in the cochlear SV of mice treated with D-gal. Hearing function was measured using the auditory brainstem response (ABR). Immunofluorescence was used to examine apoptosis and oxidative damage. Transmission electron microscopy was also used to investigate the mitochondrial ultrastructure. DNA fragmentation was determined using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay. Mitochondrial membrane potential (MMP) and ATP were also measured. RESULTS: We found that D-gal-treated mice exhibited a significant shift in the mean amplitude and latency of the ABR; a remarkable increase in the levels of NADPH oxidase (NOX-2), Uncoupling protein 2 (UCP2) and cleaved caspase-3 (c-Cas3) was observed, as well as an increase in the number of TUNEL-positive cells were observed in the SV of mice. Both the expression of the DNA oxidative damage biomarker 8-hydroxy-2-deoxyguanosine (8-OHdG) and a commonly occurring mitochondrial DNA deletion were markedly elevated in the SV of mice that had been treated with D-gal to induce aging. Conversely, the ATP level and MMP were significantly reduced in D-gal-induced aging mice. We also found alterations in the mitochondrial ultrastructure in the SV of aging mice, which include swollen and distorted mitochondrial shape, shortened and thickened microvilli, and the accumulation of lysosomes in the SV. CONCLUSION: Our findings suggest that the impairment of cochlear SV during presbycusis may be caused by mitochondrial oxidative damage and subsequent apoptosis.

Blockage of calcium-sensing receptor improves chronic intermittent hypoxia-induced cognitive impairment by PERK-ATF4-CHOP pathway.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is involved in cognitive impairment of children. Chronic intermittent hypoxia (CIH) is considered as the critical pathophysiological mechanism of OSAHS. Calcium sensitive receptor (CaSR) mediated apoptosis in many neurological disease models by endoplasmic reticulum stress (ERS)-related pathway. However, little is known about the role of CaSR in OSAHS-induced cognitive dysfunction. In this study, we explored the effect of CaSR on CIH-induced cognitive impairment and possible mechanisms on regulation of PERK-ATF4-CHOP pathway in vivo and in vitro. CIH exposed for 9 h in PC12 cells and resulted in the cell apoptosis, simulating OSAHS-induced neuronal injury. CIH upregulated the level of CaSR, p-PERK, ATF4 and CHOP, contributing to the cell apoptosis. Treated with CaSR inhibitor (NPS-2143) or p-PERK inhibitor (GSK2656157) before CIH exposure, CIH-induced PC12 cell apoptosis was alleviated via inhibition of CaSR by downregulating p-PERK, ATF4 and CHOP. In addition, we established CIH mice model. With CIH exposure for 4 weeks in mice, more spatial memory errors were observed during 8-arm radial maze test. CIH significantly increased apoptotic cells in hippocampus via upregulating cleaved Caspase-3 and downregulating ratio of Bcl-2 to Bax. Besides, treatment of CaSR inhibitor alleviated the hippocampal neuronal apoptosis following CIH with downregulated p-PERK, ATF4 and CHOP, suggesting that CaSR contributed to CIH-induced neuronal apoptosis in hippocampus via ERS pathway. Sum up, our results demonstrated that CaSR accelerated hippocampal apoptosis via PERK-ATF4-CHOP pathway, holding a critical function on CIH-mediated cognitive impairment. Conversely, inhibition of CaSR suppressed PERK-ATF4-CHOP pathway and alleviated cognitive impairment.

A Dynamic Prediction Model Supporting Individual Life Expectancy Prediction Based on Longitudinal Time-Dependent Covariates.

In the field of clinical chronic diseases, common prediction results (such as survival rate) and effect size hazard ratio (HR) are relative indicators, resulting in more abstract information. However, clinicians and patients are more interested in simple and intuitive concepts of (survival) time, such as how long a patient may live or how much longer a patient in a treatment group will live. In addition, due to the long follow-up time, resulting in generation of longitudinal time-dependent covariate information, patients are interested in how long they will survive at each follow-up visit. In this study, based on a time scale indicator-restricted mean survival time (RMST)-we proposed a dynamic RMST prediction model by considering longitudinal time-dependent covariates and utilizing joint model techniques. The model can describe the change trajectory of longitudinal time-dependent covariates and predict the average survival times of patients at different time points (such as follow-up visits). Simulation studies through Monte Carlo cross-validation showed that the dynamic RMST prediction model was superior to the static RMST model. In addition, the dynamic RMST prediction model was applied to a primary biliary cirrhosis (PBC) population to dynamically predict the average survival times of the patients, and the average C-index of the internal validation of the model reached 0.81, which was better than that of the static RMST regression. Therefore, the proposed dynamic RMST prediction model has better performance in prediction and can provide a scientific basis for clinicians and patients to make clinical decisions.

Analysis of dynamic restricted mean survival time based on pseudo-observations.

In clinical follow-up studies with a time-to-event end point, the difference in the restricted mean survival time (RMST) is a suitable substitute for the hazard ratio (HR). However, the RMST only measures the survival of patients over a period of time from the baseline and cannot reflect changes in life expectancy over time. Based on the RMST, we study the conditional restricted mean survival time (cRMST) by estimating life expectancy in the future according to the time that patients have survived, reflecting the dynamic survival status of patients during follow-up. In this paper, we introduce the estimation method of cRMST based on pseudo-observations, the statistical inference concerning the difference between two cRMSTs (cRMSTd), and the establishment of the robust dynamic prediction model using the landmark method. Simulation studies are conducted to evaluate the statistical properties of these methods. The results indicate that the estimation of the cRMST is accurate, and the dynamic RMST model has high accuracy in coefficient estimation and good predictive performance. In addition, an example of patients with chronic kidney disease who received renal transplantations is employed to illustrate that the dynamic RMST model can predict patients' expected survival times from any prediction time, considering the time-dependent covariates and time-varying effects of covariates.

Prevalence of Nonsteroidal Antiinflammatory Drugs Prescribed for Osteoarthritis: A Systematic Review and Meta-Analysis of Observational Studies.

OBJECTIVE: Our systematic review aimed to investigate the proportion of participants with osteoarthritis who were prescribed nonsteroidal antiinflammatory drugs (NSAIDs) by their health care provider. METHODS: Electronic databases were searched for observational studies reporting NSAID prescribing to participants with diagnosed osteoarthritis of any region. Risk of bias was assessed using a tool designed for observational studies measuring prevalence. Random and fixed-effects meta-analysis was used. Meta-regression investigated study-level factors associated with prescribing. The overall evidence quality was assessed using Grading of Recommendations Assessment, Development, and Evaluation criteria. RESULTS: Fifty-one studies were included, published between 1989 and 2022, with 6,494,509 participants. The mean age of participants was 64.7 years (95% confidence interval [95% CI] 62.4, 67.0; n = 34 studies). Most studies were from Europe and Central Asia (n = 23 studies), and North America (n = 12 studies). Most studies were judged to be at low risk of bias (75%). Heterogeneity was eliminated when removing studies with a high risk of bias, to give a pooled estimate of NSAIDs prescribing to participants with osteoarthritis of 43.8% (95% CI 36.8, 51.1; moderate quality of evidence). Meta-regression determined that prescribing was associated with year (decreased prescribing over time; P = 0.05) and geographic region (P = 0.03; higher in Europe and Central Asia and in South Asia than in North America) but not with clinical setting. CONCLUSION: Data from over 6.4 million participants with osteoarthritis between 1989 and 2022 indicate that NSAID prescribing has decreased over time and that prescribing differs between geographic locations.

Analysis of epidemiological trends of and associated factors for tooth loss among 35- to 44-year-old adults in Guangdong, Southern China, 1995-2015: a population-based cross-sectional survey.

BACKGROUND: Tooth loss is a known marker of oral and systemic health, but large-scale population-based and cross-sectional multi-year comparative studies on tooth loss have yet to be much studied in China. This study explores the changing trends in tooth loss status and the associated factors influencing the prevalence of tooth loss over the past two decades in Guangdong, Southern China. METHODS: Data from three cross-sectional, representative oral epidemiological surveys in Guangdong Province were analyzed, including 400 in 1995, 720 in 2005, and 288 in 2015, for a total of 1408 participants. Sample selection is based on the National Census of China published by the National Bureau of Statistics. In this study, each year, the number of missing teeth (MT) and the prevalence of tooth loss (MT > 0) were calculated. Basic demographic information, socioeconomic status, caries and periodontal status, personal lifestyle factors, and dental health care behaviors were analyzed by multivariate logistic regression to estimate their associations with tooth loss. Statistical significance was evaluated with 2-sided tests with a significance level of P < 0.05. RESULTS: This study found that the mean number of missing teeth and the prevalence of tooth loss among adults aged 35-44 years in Guangdong Province did not change significantly in the first decade (1995-2005) but decreased significantly in the second decade (2005-2015) (0.94 and 40.8% in 1995, 0.99 and 42.9% in 2005, and 0.63 and 33.3% in 2015, respectively). The mean number of MT by tooth position was highest for the first and second molars, and both were larger in the mandible than in the maxilla. In 1995, populations with low educational attainment and the presence of caries or periodontal pocket (periodontal probing depth ≥ 4 mm) were associated with a higher chance of MT > 0. In 2005, those with low educational attainment, the presence of caries, and 40-44 years old were associated with a higher chance of MT > 0. Moreover, in 2015, females, rural residents, and those with caries or periodontal pocket were associated with a higher chance of MT > 0. CONCLUSIONS: Although tooth retention has improved recently (2005-2015) and the preventive effect of education level on tooth loss has increased over time, efforts to prevent tooth loss in adults need to be strengthened. Particular attention should be given to preventive interventions for women, rural residents, and those suffering from caries or periodontal pocket.

Inhibition of Calcium-Sensing Receptor Alleviates Chronic Intermittent Hypoxia-Induced Cognitive Dysfunction via CaSR-PKC-ERK1/2 Pathway.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is typically characterized by chronic intermittent hypoxia (CIH), associated with cognitive dysfunction in children. Calcium-sensing receptor (CaSR) mediates the apoptosis of hippocampal neurons in various diseases. However, the effect of CaSR on OSAHS remains elusive. In the present study, we investigated the role of CaSR in CIH-induced memory dysfunction and underlying mechanisms on regulation of PKC-ERK1/2 signaling pathway in vivo and in vitro. CIH exposures for 4 weeks in mice, modeling OSAHS, contributed to cognitive dysfunction. CIH accelerated apoptosis of hippocampal neurons and resulted in the synaptic plasticity deficit via downregulated synaptophysin (Syn) protein level. The mice were intraperitoneally injected with CaSR inhibitor (NPS2143) 30 min before CIH exposure and the results demonstrated CaSR inhibitor alleviated the apoptosis and synaptic plasticity deficit in the hippocampus of CIH mice. We established intermittent hypoxia PC12 cell model and found that the activation of CaSR accelerated CIH-induced PC12 apoptosis and synaptic plasticity deficit by upregulated p-ERK1/2 and PKC. Overall, our findings revealed that CaSR held a critical function on CIH-induced cognitive dysfunction in mice by accelerating hippocampal neuronal apoptosis and reducing synaptic plasticity via augmenting CaSR-PKC-ERK1/2 pathway; otherwise, inhibition of CaSR alleviated CIH-induced cognitive dysfunction.