Temperature instability of a mutation at a multidomain junction in Na,K-ATPase isoform ATP1A3 (p.Arg756His) produces a fever-induced neurological syndrome.

ATP1A3 encodes the α3 isoform of Na,K-ATPase. In the brain, it is expressed only in neurons. Human ATP1A3 mutations produce a wide spectrum of phenotypes, but particular syndromes are associated with unique substitutions. For arginine 756, at the junction of membrane and cytoplasmic domains, mutations produce encephalopathy during febrile infections. Here we tested the pathogenicity of p.Arg756His (R756H) in isogenic mammalian cells. R756H protein had sufficient transport activity to support cells when endogenous ATP1A1 was inhibited. It had half the turnover rate of wildtype, reduced affinity for Na+, and increased affinity for K+. There was modest endoplasmic reticulum retention during biosynthesis at 37 °C but little benefit from the folding drug phenylbutyrate (4-PBA), suggesting a tolerated level of misfolding. When cells were incubated at just 39 °C, however, α3 protein level dropped without loss of ß subunit, paralleled by an increase of endogenous α1. Elevated temperature resulted in internalization of α3 from the surface along with some ß subunit, accompanied by cytoplasmic redistribution of a marker of lysosomes and endosomes, lysosomal-associated membrane protein 1. After return to 37 °C, α3 protein levels recovered with cycloheximide-sensitive new protein synthesis. Heating in vitro showed activity loss at a rate 20- to 30-fold faster than wildtype, indicating a temperature-dependent destabilization of protein structure. Arg756 appears to confer thermal resistance as an anchor, forming hydrogen bonds among four linearly distant parts of the Na,K-ATPase structure. Taken together, our observations are consistent with fever-induced symptoms in patients.

Characteristics of Malassezia furfur at various pH and effects of Malassezia lipids on skin cells.

Malassezia species are commensal and opportunistic fungi found in human skin. All Malassezia species lack fatty acid synthesis genes and survive by utilizing several lipases to degrade and absorb fatty acids from external lipid sources, but little research has been done on their optimal active pH and temperature. Our skin protects itself from external stimuli and maintains homeostasis, involving bacteria and fungi such as Malassezia species that inhabit our skin. Hence, dysbiosis in the skin microbiome can lead to various skin diseases. The skin's pH is slightly acidic compared to neutral, and changes in pH can affect the metabolism of Malassezia species. We used keratinocyte cell lines to determine the effect of lipids bio-converted by Malassezia furfur, Malassezia japonica, and Malassezia yamatoensis under pH conditions similar to those of healthy skin. Lipids bio-converted from Malassezia species were associated with the regulation of transcripts related to inflammation, moisturizing, and promoting elasticity. Therefore, to determine the effect of pH on lipid metabolism in M. furfur, which is associated with seborrheic dermatitis, changes in biomass, lipid content, and fatty acid composition were determined. The results showed that pH 7 resulted in low growth and reduced lipid content, which had a negative impact on skin health. Given that bio-converted Malassezia-derived lipids show positive effects at the slightly acidic pH typical of healthy skin, it is important to study their effects on skin cells under various pH conditions. KEY POINTS: • pH 6, Malassezia spp. bio-converted lipid have a positive effect on skin cells • Malassezia spp. have different lipid, fatty acid, and growth depending on pH • Malassezia spp. can play a beneficial role by secreting lipids to the outside.

Adaptive autophagy reprogramming in Schwann cells during peripheral demyelination.

The myelin sheath is an essential structure for the rapid transmission of electrical impulses through axons, and peripheral myelination is a well-programmed postnatal process of Schwann cells (SCs), the myelin-forming peripheral glia. SCs transdifferentiate into demyelinating SCs (DSCs) to remove the myelin sheath during Wallerian degeneration after axonal injury and demyelinating neuropathies, and macrophages are responsible for the degradation of myelin under both conditions. In this study, the mechanism by which DSCs acquire the ability of myelin exocytosis was investigated. Using serial ultrastructural evaluation, we found that autophagy-related gene 7-dependent formation of a "secretory phagophore (SP)" and tubular phagophore was necessary for exocytosis of large myelin chambers by DSCs. DSCs seemed to utilize myelin membranes for SP formation and employed p62/sequestosome-1 (p62) as an autophagy receptor for myelin excretion. In addition, the acquisition of the myelin exocytosis ability of DSCs was associated with the decrease in canonical autolysosomal flux and was demonstrated by p62 secretion. Finally, this SC demyelination mechanism appeared to also function in inflammatory demyelinating neuropathies. Our findings show a novel autophagy-mediated myelin clearance mechanism by DSCs in response to nerve damage.

Deep learning for osteoarthritis classification in temporomandibular joint.

OBJECTIVES: This study aimed to develop a diagnostic support tool using pretrained models for classifying panoramic images of the temporomandibular joint (TMJ) into normal and osteoarthritis (OA) cases. SUBJECTS AND METHODS: A total of 858 panoramic images of the TMJ (395 normal and 463 TMJ-OA) were obtained from 518 individuals from January 2015 to December 2018. The data were randomly divided into training, validation, and testing sets (6:2:2). We used pretrained Resnet152 and EfficientNet-B7 as transfer learning models. The accuracy, specificity, sensitivity, area under the curve, and gradient-weighted class activation mapping (grad-CAM) of both trained models were evaluated. The performances of the trained models were compared to that of dentists (both TMD specialists and general dentists). RESULTS: The classification accuracies of ResNet-152 and EfficientNet-B7 were 0.87 and 0.88, respectively. The trained models exhibited the highest accuracy in OA classification. In the grad-CAM analysis, the trained models focused on specific areas in osteoarthritis images where erosion or osteophyte were observed. CONCLUSIONS: The artificial intelligence model improved the diagnostic power of TMJ-OA when trained with two-dimensional panoramic condyle images and can be effectively applied by dentists as a screening diagnostic tool for TMJ-OA.

Obstructive Sleep Apnea Is Associated With Late-Onset Preeclampsia in Overweight Pregnant Women in Korea.

BACKGROUND: Obstructive sleep apnea (OSA) is closely related to maternal obesity in pregnant women, and the association increases with later pregnancy. Obesity and OSA are risk factors of pregnancy-related complications, including gestational hypertension, gestational diabetes mellitus (GDM), and fetal morbidities. We aimed to determine the prevalence of OSA and to assess the impact of OSA on pregnancy-related disorders in overweight pregnant women. METHODS: Eligible participants who were overweight [body mass index (BMI) ≥ 23 kg/m²] in gestational age 30 weeks or more, assessed OSA using a portable polysomnography at home. Clinical data were collected from pregnant women and their babies. RESULTS: The average age of 51 participants was 34.5 years (27-44 years). The number of primipara was 25 (49%) and that of multipara was 26 (51%). Eight cases of GDM (15.7%) and five cases of preeclampsia (9.8%) were reported, and six patients (11.8%) experienced preterm delivery. In results of polysomnography, 14 patients (27.5%) were diagnosed as OSA. Apnea-hypopnea index moderately correlated with BMI (r = 0.515, P < 0.001). The BMI (P < 0.005) and preeclampsia rate (P < 0.017) were higher in the OSA group compared to the control group. Odds ratios (ORs) adjusting age, BMI, parity, and abortion history were calculated. The presence of OSA increased OR of preeclampsia (OR, 13.1; 95% confidence interval, 1.1-171.3). The majority of preeclampsia patients (4/5, 80%) underwent preterm delivery. CONCLUSION: OSA is an important risk factor for preeclampsia, resulting in preterm delivery. For overweight pregnant women, an OSA evaluation should be mandatory.

Association between nuclear factor of activated T cells C2 polymorphisms and treatment response in rheumatoid arthritis patients receiving tumor necrosis factor-alpha inhibitors.

OBJECTIVES: Nuclear factor of activated T cells C2 (NFATC2) is known as a member of the transcription family and enhances tumor necrosis factor-alpha (TNF-α) synthesis in human T cells at the gene transcription level. Although NFATC2 has a potential role in rheumatoid arthritis (RA) progression and treatment, no study has investigated the association between NFATC2 gene polymorphisms and response status in RA patients receiving TNF-α inhibitors. This study aimed to examine the effects of polymorphisms in NFATC2, a TNF-α transcription factor, on response to TNF-α inhibitors. METHODS: This prospective observational study was performed in two centers. Seven single nucleotide polymorphisms (SNPs) were investigated. Good responders were defined as patients with disease activity score (DAS)28 ≤3.2 after 6 months of treatment. Logistic regression analyses were used to investigate the association between genetic polymorphisms and response to the treatment. To test the model's goodness of fit, a Hosmer-Lemeshow test was performed. RESULTS: This study included 98 patients, among whom 46 showed favorable responses to the treatment. Patients with hypertension revealed an approximately three-fold lower response to TNF-α inhibitors compared to those without hypertension (23.5 vs. 76.5%; P = 0.049). After adjusting for covariates, C allele carriers of NFATC2 rs3787186 exhibited approximately three-fold lower rates of treatment response compared to those with TT genotype (P = 0.037). The Hosmer-Lemeshow test showed that the fitness of the multivariable analysis model was satisfactory (χ2 = 9.745; 8 degrees of freedom; P = 0.283). CONCLUSION: This study suggested an association between the C allele of rs3787186 and treatment response in RA patients receiving TNF-α inhibitors.

Potential neuron-autonomous Purkinje cell degeneration by 2',3'-cyclic nucleotide 3'-phosphodiesterase promoter/Cre-mediated autophagy impairments.

Studies of neuroglial interaction largely depend on cell-specific gene knockout (KO) experiments using Cre recombinase. However, genes known as glial-specific genes have recently been reported to be expressed in neuroglial stem cells, leading to the possibility that a glia-specific Cre driver results in unwanted gene deletion in neurons, which may affect sound interpretation. 2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is generally considered to be an oligodendrocyte (OL) marker. Accordingly, Cnp promoter-controlled Cre recombinase has been used to create OL-specific gene targeting mice. However, in this study, using Rosa26-tdTomato-reporter/Cnp-Cre mice, we found that many forebrain neurons and cerebellar Purkinje neurons belong to the lineages of Cnp-expressing neuroglial stem cells. To answer whether gene targeting by Cnp-Cre can induce neuron-autonomous defects, we conditionally deleted an essential autophagy gene, Atg7, in Cnp-Cre mice. The Cnp-Cre-mediated Atg7 KO mice showed extensive p62 inclusion in neurons, including cerebellar Purkinje neurons with extensive neurodegeneration. Furthermore, neuronal areas showing p62 inclusion in Cnp-Cre-mediated Atg7 KO mice overlapped with the neuronal lineage of Cnp-expressing neuroglial stem cells. Moreover, Cnp-Cre-mediated Atg7-KO mice did not develop critical defects in myelination. Our results demonstrate that a large population of central neurons are derived from Cnp-expressing neuroglial stem cells; thus, conditional gene targeting using the Cnp promoter, which is known to be OL-specific, can induce neuron-autonomous phenotypes.

A comparison of the influencing factors of chronic pain and quality of life between older Koreans and Korean-Americans with chronic pain: a correlational study.

BACKGROUND: Chronic pain is one of the most common health problems for older adults worldwide and is likely to result in lower quality of life. Living in a different culture may also influence chronic pain and quality of life in older adults. The purpose of this study was to explore how multifaceted elements affect chronic pain and quality of life in older Koreans living in Korea and in older Korean-Americans (KAs) living in the USA. METHODS: We conducted a secondary data analysis of data from 270 adults aged 65 years or over (138 Koreans and 132 KAs). We compared the effects of multifaceted elements on pain and quality of life by testing structural equation models (SEMs) for each group, using a maximum likelihood estimation and bootstrapping. RESULTS: SEMs for both Korean and KAs showed that age and depressive symptoms directly affected quality of life. The number of comorbidities and depressive symptoms had mediating effects on quality of life through chronic pain in both groups. In older Koreans only, perceived financial status directly affected quality of life. In older KAs only, sleep quality indirectly affected quality of life through chronic pain. CONCLUSION: The data showed that multimorbidity and depressive symptoms play critical roles for explaining chronic pain in older Koreans and KAs and ultimately negatively influence quality of life. Future intervention program to improve quality of life in older adults with chronic pain should consider the different cultural aspects affecting quality of life for Koreans and KAs.

COVID-19 Prognosis in Association with Antidepressant Use.

INTRODUCTION: Various subtypes of severe acute respiratory syndrome coronavirus 2 and variations among immune systems in different ethnicities need to be considered to understand the outcomes of coronavirus disease 2019 (COVID-19). This study aimed to provide evidence for the association between the use of antidepressants and the severity of COVID-19. METHODS: We used the National Health Information Data-COVID database. Patients with one or more prescriptions of any antidepressant were selected as the exposure group. Detailed analyses were performed to determine the type of medication associated with the prognosis. RESULTS: The use of selective serotonin reuptake inhibitors (SSRIs) was associated with a lower risk of severe outcomes of COVID-19, whereas the use of tricyclic antidepressants (TCAs) increased the risk of poor prognosis of COVID-19. Detailed analyses showed that escitalopram was significantly associated with better clinical outcomes, and nortriptyline was linked to more severe COVID-19 outcomes. CONCLUSION: This study revealed an association between antidepressants and COVID-19 prognosis. SSRIs were significantly associated with a lower risk of severe outcomes, whereas TCAs were related to the poor prognosis of COVID-19.

Neoadjuvant versus adjuvant chemotherapy in upper tract urothelial carcinoma: A nationwide cohort study.

PURPOSE: This study aimed to evaluate the trend of adjuvant chemotherapy (AC) and neoadjuvant chemotherapy (NAC) in patients who underwent radical nephroureterectomy with bladder cuff excision (NUx) for upper tract urothelial carcinoma (UTUC) to compare the perioperative outcomes and overall survival (OS) between AC and NAC using nationwide population-based data. MATERIALS AND METHODS: We collected data on patients diagnosed with UTUC and treated with NUx between 2004 and 2016 using the National Health Insurance Service database, and evaluated the overall treatment trends. The AC and NAC groups were propensity score-matched. Cox proportional hazard and Kaplan-Meier analyses were used to assess survival. RESULTS: Of the 8,705 enrolled patients, 6,627 underwent NUx only, 94 underwent NAC, and 1,984 underwent AC. The rate of NUx without perioperative chemotherapy increased from 70.8 to 78.2% (R2 = 0.632; p < 0.001). The rates of dialysis (p = 0.398), TUR-BT (p = 1.000), and radiotherapy (p = 0.497) after NUx were similar. In the Kaplan-Meier curve, the NAC and AC groups showed no significant difference (p = 0.480). In multivariate analysis, treatment with AC or NAC was not associated with OS (hazard ratio 0.83, 95% confidence interval 0.49-1.40, p = 0.477). CONCLUSION: The use of NUx without perioperative chemotherapy has tended to increase in South Korea. Dialysis, TUR-BT, and radiotherapy rates after NUx were similar between the NAC and AC groups. There was no significant difference in OS between the NAC and AC groups. Proper perioperative chemotherapy according to patient and tumor conditions should be determined by obtaining more evidence of UTUC.