A common mechanism of Sec61 translocon inhibition by small molecules.

The Sec61 complex forms a protein-conducting channel in the endoplasmic reticulum membrane that is required for secretion of soluble proteins and production of many membrane proteins. Several natural and synthetic small molecules specifically inhibit Sec61, generating cellular effects that are useful for therapeutic purposes, but their inhibitory mechanisms remain unclear. Here we present near-atomic-resolution structures of human Sec61 inhibited by a comprehensive panel of structurally distinct small molecules-cotransin, decatransin, apratoxin, ipomoeassin, mycolactone, cyclotriazadisulfonamide and eeyarestatin. All inhibitors bind to a common lipid-exposed pocket formed by the partially open lateral gate and plug domain of Sec61. Mutations conferring resistance to the inhibitors are clustered at this binding pocket. The structures indicate that Sec61 inhibitors stabilize the plug domain in a closed state, thereby preventing the protein-translocation pore from opening. Our study provides the atomic details of Sec61-inhibitor interactions and the structural framework for further pharmacological studies and drug design.

Co-translational biogenesis of lipid droplet integral membrane proteins.

Membrane proteins destined for lipid droplets (LDs), a major intracellular storage site for neutral lipids, are inserted into the endoplasmic reticulum (ER) and then trafficked to LDs where they reside in a hairpin loop conformation. Here, we show that LD membrane proteins can be delivered to the ER either co- or post-translationally and that their membrane-embedded region specifies pathway selection. The co-translational route for LD membrane protein biogenesis is insensitive to a small molecule inhibitor of the Sec61 translocon, Ipomoeassin F, and instead relies on the ER membrane protein complex (EMC) for membrane insertion. This route may even result in a transient exposure of the short N termini of some LD membrane proteins to the ER lumen, followed by putative topological rearrangements that would enable their transmembrane segment to form a hairpin loop and N termini to face the cytosol. Our study reveals an unexpected complexity to LD membrane protein biogenesis and identifies a role for the EMC during their co-translational insertion into the ER.

A high-resolution PheWAS approach to alcohol-related polygenic risk scores reveals mechanistic influences of alcohol reinforcing value and drinking motives.

AIMS: This study uses a high-resolution phenome-wide approach to evaluate the motivational mechanisms of polygenic risk scores (PRSs) that have been robustly associated with coarse alcohol phenotypes in large-scale studies. METHODS: In a community-based sample of 1534 Europeans, we examined genome-wide PRSs for the Alcohol Use Disorders Identification Test (AUDIT), drinks per week, alcohol use disorder (AUD), problematic alcohol use (PAU), and general addiction, in relation to 42 curated phenotypes. The curated phenotypes were in seven categories: alcohol consumption, alcohol reinforcing value, drinking motives, other addictive behaviors, commonly comorbid psychiatric syndromes, impulsivity, and personality traits. RESULTS: The PRS for each alcohol phenotype was validated via its within-sample association with the corresponding phenotype (adjusted R2s = 0.35-1.68%, Ps = 0.012-3.6 × 10-7) with the exception of AUD. All PRSs were positively associated with alcohol reinforcing value and drinking motives, with the strongest effects from AUDIT-consumption (adjusted R2s = 0.45-1.33%, Ps = 0.006-3.6 × 10-5) and drinks per week PRSs (adjusted R2s = 0.52-2.28%, Ps = 0.004-6.6 × 10-9). Furthermore, the PAU and drinks per week PRSs were positively associated with adverse childhood experiences (adjusted R2s = 0.6-0.7%, Ps = 0.0001-4.8 × 10-4). CONCLUSIONS: These results implicate alcohol reinforcing value and drinking motives as genetically-influenced mechanisms using PRSs for the first time. The findings also highlight the value of dissecting genetic influence on alcohol involvement through diverse phenotypic risk pathways but also the need for future studies with both phenotypic richness and larger samples.

[An analysis on clinical characteristics and prognosis-related risk factors in patients with drug-induced liver injury].

Objective: To explore the drugs and clinical characteristics causing drug-induced liver injury (DILI) in recent years, as well as identify drug-induced liver failure, and chronic DILI risk factors, in order to better manage them timely. Methods: A retrospective investigation and analysis was conducted on 224 cases diagnosed with DILI and followed up for at least six months between January 2018 and December 2020. Univariate and multivariate logistic regression analyses were used to identify risk factors for drug-induced liver failure and chronic DILI. Results: Traditional Chinese medicine (accounting for 62.5%), herbal medicine (accounting for 84.3% of traditional Chinese medicine), and some Chinese patent medicines were the main causes of DILI found in this study. Severe and chronic DILI was associated with cholestatic type. Preexisting gallbladder disease, initial total bilirubin, initial prothrombin time, and initial antinuclear antibody titer were independent risk factors for DILI. Prolonged time interval between alkaline phosphatase (ALP) and alanine aminotransferase (ALT) falling from the peak to half of the peak (T(0.5ALP) and T(0.5ALT)) was an independent risk factor for chronic DILI [area under the receiver operating characteristic curve (AUC) = 0.787, 95%CI: 0.697~0.878, P < 0.001], with cutoff values of 12.5d and 9.5d, respectively. Conclusion: Traditional Chinese medicine is the main contributing cause of DILI. The occurrence risk of severe DILI is related to preexisting gallbladder disease, initial total bilirubin, prothrombin time, and antinuclear antibodies. T(0.5ALP) and T(0.5ALT) can be used as indicators to predict chronic DILI.

[Technological development of robot-assisted radical prostatectomy].

The surgical outcomes of robot-assisted radical prostatectomy have shown remarkable improvement over the last two decades since its advent, due to advances in surgical concepts, techniques, and equipment. Today, ongoing research aims to compare the benefits and drawbacks of various surgical approaches, such as anterior, posterior, lateral, transvesical, and transperineal approaches, in terms of tumor control, functional recovery, and complication reduction in order to achieve the goal of pentafecta (no postoperative complications and negative surgical margins in addition to trifecta) to the maximum extent. It is imperative to explore and integrate novel technologies such as 5G remote surgery and artificial intelligence into the clinical practice of robot-assisted radical prostatectomy while ensuring patient safety, which has immense potential for substantial benefits to patients with prostate cancer.

[Functional outcomes of robot-assisted radical prostatectomy with preservation of pelvic stabilized structure and early elevated retrograde liberation of neurovascular bundle].

Objectives: To examine the functional outcomes of robot-assisted radical prostatectomy (RARP) with preservation of pelvic floor stabilized structure and early elevated retrograde liberation of the neurovascular bundle (PEEL). Methods: This study was a retrospective cohort study. Between June 1, 2022, and March 20, 2023, 27 cases of RARP with PEEL and 153 cases of RARP with preservation of pelvic floor stabilized structure (PPSS) were included in this study. All patients were males, aged (62.5±5.2) years (range: 50 to 73 years). There were 18 cases of ≤T2b stage and 9 cases of T2c stage. After 1∶1 propensity score matching, the postoperative functional outcomes of 27 cases of RARP with PEEL and 27 cases of RARP with PPSS were compared. All surgeries were performed by a single surgeon and included patients were clinically staged as cT1-2N0M0 without preoperative urinary incontinence or erectile dysfunction. In RARP with PEEL, the prostate was cut near the midline at the front when dissecting the neurovascular bundle, dissection was performed between the visceral layer of the pelvic fascia and the prostatic fascia, preserving the parietal layer and the visceral layer of the pelvic fascia, and the neurovascular bundle was retrogradely released from the apex. The cumulative probability curve was plotted using the Kaplan-Meier method and the Log-rank test was used to compare the differences in functional outcomes between the two groups. Univariate and multivariate analysis with the Cox proportional hazards model was used to compare postoperative urinary continence and sexual function. Results: The recovery time of continence and potency was significantly longer in the PPSS group than in the PEEL group (all P<0.05). The continence rate of the PEEL group was significantly higher than that of the PPSS group (92.59% vs. 68.10%, P=0.026) at 3 months after surgery. The potency rate of the PEEL group was also significantly higher than that of the PPSS group (40.70% vs. 15.10%, P=0.037) at 3 months after surgery. In the univariate analysis, compared to the PPSS technique, the PEEL technique was associated with a shorter recovery time of continence (HR=1.94, 95%CI: 1.08 to 3.48, P=0.027) and a shorter recovery time of potency (HR=2.06, 95%CI: 1.03 to 4.13, P=0.042). In the multivariate analysis, the PEEL technique was an independent prognosis factor for postoperative recovery of continence (HR=2.05, 95%CI: 1.01 to 4.17, P=0.047) and potency (HR=3.57, 95%CI: 1.43 to 8.92, P=0.007). All the cases of the PPSS group and the PEEL group were performed successfully with negative surgical margins. Conclusion: Compared with PPSS, PEEL may be more conducive to the recovery of urinary continence and sexual function after RARP.

Ipomoeassin-F inhibits the in vitro biogenesis of the SARS-CoV-2 spike protein and its host cell membrane receptor.

In order to produce proteins essential for their propagation, many pathogenic human viruses, including SARS-CoV-2, the causative agent of COVID-19 respiratory disease, commandeer host biosynthetic machineries and mechanisms. Three major structural proteins, the spike, envelope and membrane proteins, are amongst several SARS-CoV-2 components synthesised at the endoplasmic reticulum (ER) of infected human cells prior to the assembly of new viral particles. Hence, the inhibition of membrane protein synthesis at the ER is an attractive strategy for reducing the pathogenicity of SARS-CoV-2 and other obligate viral pathogens. Using an in vitro system, we demonstrate that the small molecule inhibitor ipomoeassin F (Ipom-F) potently blocks the Sec61-mediated ER membrane translocation and/or insertion of three therapeutic protein targets for SARS-CoV-2 infection; the viral spike and ORF8 proteins together with angiotensin-converting enzyme 2, the host cell plasma membrane receptor. Our findings highlight the potential for using ER protein translocation inhibitors such as Ipom-F as host-targeting, broad-spectrum antiviral agents.This article has an associated First Person interview with the first author of the paper.

Posttranslational insertion of small membrane proteins by the bacterial signal recognition particle.

Small membrane proteins represent a largely unexplored yet abundant class of proteins in pro- and eukaryotes. They essentially consist of a single transmembrane domain and are associated with stress response mechanisms in bacteria. How these proteins are inserted into the bacterial membrane is unknown. Our study revealed that in Escherichia coli, the 27-amino-acid-long model protein YohP is recognized by the signal recognition particle (SRP), as indicated by in vivo and in vitro site-directed cross-linking. Cross-links to SRP were also observed for a second small membrane protein, the 33-amino-acid-long YkgR. However, in contrast to the canonical cotranslational recognition by SRP, SRP was found to bind to YohP posttranslationally. In vitro protein transport assays in the presence of a SecY inhibitor and proteoliposome studies demonstrated that SRP and its receptor FtsY are essential for the posttranslational membrane insertion of YohP by either the SecYEG translocon or by the YidC insertase. Furthermore, our data showed that the yohP mRNA localized preferentially and translation-independently to the bacterial membrane in vivo. In summary, our data revealed that YohP engages an unique SRP-dependent posttranslational insertion pathway that is likely preceded by an mRNA targeting step. This further highlights the enormous plasticity of bacterial protein transport machineries.

Association between chronic disease and depression among older adults in China: the moderating role of social participation.

OBJECTIVES: Depression is an increasingly serious mental health problem worldwide. Therefore, this study aimed to explore the association between chronic disease and depression and to further test the moderating role of social participation in this association. STUDY DESIGN: This is a cross-sectional study. METHODS: We screened 6421 subjects from the 2018 wave of the China Health and Retirement Longitudinal Study database. Social participation and depressive symptoms were assessed using the 12-item self-made scale and 10-item Center for Epidemiological Studies Depression Scale, respectively. Hierarchical regression was used to determine the main effect of chronic disease and depression and the moderating effect of social participation on the relationship between chronic disease and depression. RESULTS: In this study, 3172 (49.40%) eligible participants were male, 4680 (72.90%) older adults were concentrated in the 65-74 years group, and 68.20% reported good health status. In addition, gender, area, education level, marital status, health status, health insurance, health service utilization, and physical activity intensity were significant factors associated with participants' depression status (P < 0.05). The results also showed that a higher number of chronic diseases were associated with a higher depression score after adjusting for confounders (single disease: ß = 0.074, P < 0.001; multimorbidity: ß = 0.171, P < 0.001) and that social participation played a moderating role in this association (ß = -0.030, P < 0.05). CONCLUSIONS: This study tentatively suggests that a higher number of chronic diseases are associated with rising depression scores in the older Chinese population. In addition, the moderating effect of social participation suggests that more active social engagement should be promoted in this population to alleviate the depressive mood.

Neutral particles pushed or pulled by laser pulses: erratum.

We present an erratum to our Letter [Opt. Lett.41, 230 (2016)10.1364/OL.41.000230]. This erratum corrects three typing errors. The corrections have no influence on the results and conclusions of the original Letter.

Hyperhidrosis in Parkinson's disease: a 3-year prospective cohort study.

BACKGROUND: Although hyperhidrosis is a common symptom in patients with Parkinson's disease (PD), no study has yet examined it longitudinally. OBJECTIVES: We conducted a 3-year prospective cohort study to investigate the development, evolution and correlates of hyperhidrosis in patients with PD. METHODS: A total of 224 patients with early-stage PD were enrolled at baseline and followed up annually for three consecutive years. Hyperhidrosis was assessed using hyperhidrosis question (item 30) of the Non-Motor Symptoms Scale (NMSS). The generalized estimating equations model was applied to investigate the correlates of both presence and severity of hyperhidrosis. RESULTS: The frequency of hyperhidrosis in PD had an overall increasing tendency from 24.1% at baseline to 34.4% after 3 years, although hyperhidrosis was not always persistent in all patients over the 3-year study period. The presence of hyperhidrosis was found to be associated with dyskinesia (OR 2.27 [1.02-5.04], P = 0.045), the sexual function domain subscore of the NMSS (OR 1.04 [1.01-1.07], P = 0.016), the Hamilton Anxiety Rating Scale (HARS) score (OR 1.08 [1.03-1.13], P = 0.001) and the Unified Parkinson's Disease Rating Scale part III score (OR 1.02 [1.00-1.04], P = 0.036). Only the HARS score was associated with the severity of hyperhidrosis (B 0.08 [0.03-0.12], P = 0.001). CONCLUSIONS: Hyperhidrosis is common in PD, and its frequency increases along with disease duration. Hyperhidrosis in PD is associated not only with motor severity and motor complication such as dyskinesia, but also with non-motor symptoms such as sexual dysfunction and anxiety.

Synthesis, Biological Evaluation and Docking Studies of Ring-Opened Analogues of Ipomoeassin F.

The plant-derived macrocyclic resin glycoside ipomoeassin F (Ipom-F) binds to Sec61α and significantly disrupts multiple aspects of Sec61-mediated protein biogenesis at the endoplasmic reticulum, ultimately leading to cell death. However, extensive assessment of Ipom-F as a molecular tool and a therapeutic lead is hampered by its limited production scale, largely caused by intramolecular assembly of the macrocyclic ring. Here, using in vitro and/or in cellula biological assays to explore the first series of ring-opened analogues for the ipomoeassins, and indeed all resin glycosides, we provide clear evidence that macrocyclic integrity is not required for the cytotoxic inhibition of Sec61-dependent protein translocation by Ipom-F. Furthermore, our modeling suggests that open-chain analogues of Ipom-F can interact with multiple sites on the Sec61α subunit, most likely located at a previously identified binding site for mycolactone and/or the so-called lateral gate. Subsequent in silico-aided design led to the discovery of the stereochemically simplified analogue 3 as a potent, alternative lead compound that could be synthesized much more efficiently than Ipom-F and will accelerate future ipomoeassin research in chemical biology and drug discovery. Our work may also inspire further exploration of ring-opened analogues of other resin glycosides.

Spastic paraplegia as the only symptom in two adult-onset patients carrying a novel pathogenic variant in PYCR2.

A novel pathogenic PYCR2 variant and corresponding brain images in two patients characterized by spastic paraplegia.

Wuyiencin produced by Streptomyces albulus CK-15 displays biocontrol activities against cucumber powdery mildew.

AIMS: Wuyiencin is a nucleoside antibiotic produced by Streptomyces albulus CK-15. The aim of this study was to determine whether wuyiencin can be used, as a suitable alternative to chemical pesticides, to protect cucumbers (Cucumis sativus L.) from powdery mildew caused by Sphaerotheca fuliginea. Further, the mechanisms underlying the control of cucumber powdery mildew by S. albulus CK-15 were preliminarily elucidated. METHODS AND RESULTS: Wuyiencin solutions of different concentrations were used to treat infected cucumber plants under greenhouse conditions. The results indicated that wuyiencin could significantly reduce powdery mildew disease incidence, with a maximum prevention efficacy of 94·38%. Further, scanning electron micrographs and enzyme assays showed that wuyiencin inhibited S. fuliginea spore growth and elicited the activity of plant systemic resistance-related enzymes. Additionally, real-time quantitative reverse transcription PCR suggested that wuyiencin can activate a salicylic acid-dependent plant defence response. CONCLUSIONS: Wuyiencin produced by S. albulus CK-15 possessed antifungal effects and was able to mitigate cucumber powdery mildew disease via antagonistic action. Wuyiencin also induced defence responses in the plants. SIGNIFICANCE AND IMPACT OF THE STUDY: These results reinforce the biotechnological potential of wuyiencin as both an antagonistic agent and an inducer of plant systemic resistance.

Effect modification of the association between diurnal temperature range and hospitalisations for ischaemic stroke by temperature in Hefei, China.

OBJECTIVES: Diurnal temperature range (DTR) is an important indicator of global climate change. Many epidemiological studies have reported the associations between high DTR and human health. This study investigated the association between DTR and hospitalisations for ischaemic stroke in Hefei, China. STUDY DESIGN: This is an ecological study. METHODS: Data of daily hospital admissions for ischaemic stroke and meteorological variables from 1 January 2009 to 31 December 2017 were collected in Hefei, China. A generalised additive model combined with distributed lag non-linear model was used to quantify the effects of DTR on ischaemic stroke. The interactive effect between DTR and temperature was explored with a non-parametric bivariate response surface model. RESULTS: High DTR was associated with hospitalisations for ischaemic stroke. The adverse effect of extremely high DTR (99th percentile [17.1 °C]) occurred after 8 days (relative risk [RR] = 1.021, 95% confidence interval [CI] = 1.002, 1.041) and the maximum effect appeared after 12 days (RR = 1.029, 95% CI = 1.011, 1.046). The overall trend of the effect of DTR on ischaemic stroke was decreasing. In addition, there was a significant interactive effect of high DTR and low temperature on ischaemic stroke. CONCLUSIONS: This study suggests that the impact of high DTR should be considered when formulating targeted measures to prevent ischaemic stroke, especially for those days with high DTR and low mean temperature.

High-throughput sequencing reveals crucial miRNAs in skeletal muscle development of Bian chicken.

1. Growth performance is significant for chickens. MicroRNAs (miRNAs) have been found to play important roles in the post-transcriptional regulation of skeletal muscle growth. However, the mechanism of miRNAs in this process has not been elucidated.2. This study involved collecting leg muscle from slow- and fast-growing groups of Bian chicken at 16 weeks of age for high-throughput sequencing. A total of 42 differentially expressed miRNAs (DEMs) were identified. Among them, 22 DEMs were up-regulated and 20 DEMs were down-regulated.3. Biological process terms, relating to growth, were found by GO enrichment for target genes of DEMs and KEGG pathway analysis of target genes. This revealed some significantly enriched pathways closely related to skeletal muscle development, such as the calcium signalling pathway, ECM-receptor interaction, lysine degradation, apoptosis and tight junctions. Network interaction analysis of DEMs and target genes showed that the top fifty hub genes were targeted by thirteen DEMs.4. Four important miRNAs (novel_miR_158, novel_miR_144, novel_miR_291, and miR-205a) as well as some other valuable miRNAs, such as gga-miR-214 and gga-miR-3525 were identified. The qPCR results of five DEMs were highly consistent with that of sequencing between the two groups, which proved the reliability of miRNA-seq.5. The study will help to improve the molecular mechanism of miRNAs in chickens and guide future experiments concerning miRNA function in chicken growth.

[Analysis of screening results and risk factors of high-risk populations of lung cancer in Nanchang city from 2018 to 2019].

Objective: To collate and analyze the screening results of high-risk lung cancer populations in communities in Nanchang from 2018 to 2019, and to explore the lung-positive nodules and risk factors for lung cancer. Methods: Data of the screening subjects in 8 administrative districts and 15 street health service centers in Nanchang city, Jiangxi province from November 2018 to October 2019 were collected, people at high risk of lung cancer was assessed, clinical screening of high-risk groups of lung cancer was conducted by low-dose helical computed tomography (LDCT), and risk factors for suspected lung cancer and lung-positive nodules were analyzed. Results: Of the 25 871 people participated in screening, 5 220 were at high risk for lung cancer and 15 374 without other malignant tumors were at high risk. There were 2 417 cases participated in clinical LDCT screening, including 193 cases of lung-positive nodules, 67 cases of suspected lung cancer, 912 cases of other lung diseases, the positive rate of lung cancer or lung-positive nodules was 10.76% (260/2 417). Univariate analysis showed that age, coarse grain intake, oil intake, housing heating, passive smoking, alcohol consumption and mental trauma were associated with positive pulmonary nodules or lung cancer (all P<0.05). Multivariate analysis showed that gender, age, housing heating, smoking and drinking were related to the occurrence of lung nodules or lung cancer (all P<0.05). Conclusions: Men are more likely to develop lung cancer or lung-positive nodules than women. The age is an independent risk factor for lung-positive nodules or lung cancer. In a certain range, age will increase the incidence of lung cancer, housing heating may be the protective factor for lung cancer, while smoking and drinking are risk factors.

[The relationship of resilience with cognitive function in patients with first-episode schizophrenia].

Objective: To investigate the correlation between resilience and cognitive function in patients with schizophrenia. Methods: Fifty-nine patients with first-episode schizophrenia and 86 healthy controls were enrolled. Patients with schizophrenia were enrolled from the psychiatric outpatient and inpatient Department of the Third Affiliated Hospital of Sun Yat-sen University from September 2017 to January 2020, while healthy controls were recruited through advertising. The levels of resilience and cognitive function were compared between the two groups.Meanwhile, the partial correlation analysis of resilience and cognitive function of the two groups was performed. Results: There was no statistically significant difference in gender, marriage and age between the two groups (all P>0.05), and there were 39 males and 20 females with an average age of (23.8±7.4) years in the schizophrenia group, while 47 males and 39 females with an average age of (22.9±4.7) years in the healthy control group. However, there was a significant difference inyears of education between the two groups (P<0.05). The total score of resilience [(56.9±16.7) vs(68.0±14.4)] and scores ofthree factorsin patients with schizophrenia were significantly lower than that in healthy controls(all P<0.05). The total score of MATRICS Consensus Cognitive Battery (MCCB)[(23±12) vs (42±11)] and each subscale score in patients with schizophrenia were significantly lower than that in healthy controls(all P<0.05). Partial correlation analysis showed that the total score of resilience and tenacity were correlated with symbol coding of schizophrenia(partial correlation coefficients were 0.286, 0.289, respectively, both P<0.05). The total score of resilience and the scores of tenacity, strength and optimism were all correlated with emotion management ability of schizophrenia(partial correlation coefficients were 0.334, 0.271, 0.382, 0.308, respectively, all P<0.05). In the healthy controls, the total score of resilience, tenacity and optimism were correlated with symbol coding(partial correlation coefficients were 0.268, 0.225, 0.291, respectively, all P<0.05). Strength and optimism were correlated with Hopkins verbal learning test (HVLT)(partial correlation coefficients were 0.268, 0.225, respectively, both P<0.05). Strength was correlated with spatial span, continuous performance test(partial correlation coefficients were 0.244, 0.217, respectively, bothP<0.05). The total scores of resilience and tenacity, strength and optimism were correlated with emotional management ability(partial correlation coefficients were 0.306, 0.230, 0.286, 0.289, respectively, all P<0.05), while the total scores of resilience, strength and optimism were correlated with the total score of MCCB(partial correlation coefficients were 0.291, 0.359, 0.287, respectively, all P<0.05). Conclusion: The current study suggests that resilience and cognitive function of patients with first-episode schizophrenia areimpaired significantly. Resilience in patients with schizophrenia isrelated to partial neurocognitive function and emotion management ability in social cognitive function.

[mTOR signaling pathway-mediated autophagy involved in inhibition of osteoblast differentiation induced by cadmium in human bone marrow mesenchymal stem cells].

Objective: To investigate the role of autophagy mediated by mTOR signaling pathway in the inhibition of osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) induced by cadmium. Methods: HBMSCs were divided into 0, 2.5 or 5.0 µmol/L groups according to the exposure dose of cadmium chloride (CdCl2), and each group was treated for 1 day, 4 days and (or) 7 days. The ALP activity and mRNA and protein expression levels of osteogenesis markers (ALP, RUNX2 and OSTERIX), autophagy-related proteins (LC3 and Beclin-1) and mTOR signaling pathway related proteins (mTOR, p-mTOR and p-p70S6K) expression, alkaline phosphatase staining and alizarin red staining were detected. MHY 1485 was selected as the signaling pathway activator. The control group, CdCl2 group (5.0 µmol/L), MHY 1485 group and CdCl2+MHY 1485 combined treatment group were set. After 7 days of treatment, the expression levels of autophagy related proteins and mTOR signaling pathway related proteins of hBMSCs in each group were detected. Results: There was no significant difference in ALP activity between 0, 2.5 and 5.0 µmol/L groups on day 1 and 4 (P>0.05); On day 7, compared with the 0 µmol/L group, the ALP activity, expression of osteogenic markers (ALP, RUNX2, OSTERIX) and mTOR signaling pathway related proteins (mTOR, p-mTOR, p-p70S6K) expression decreased in the 2.5 and 5.0 µmol/L group (P<0.05). Compared with the 0 µmol/L group, the staining of the 2.5 and 5.0 µmol/L groups became lighter, and the formation of ALP and mineralized nodules was reduced. Compared with the CdCl2 group, the autophagy related protein expression in the CdCl2+MHY 1485 combined treatment group decreased, and the mTOR signaling pathway related protein expression increased. The difference was statistically significant (P<0.05). Conclusion: The inhibition of osteogenic differentiation of hBMSCs by cadmium may be related to autophagy mediated by mTOR signaling pathway.

Analytical strategies to include the X-chromosome in variance heterogeneity analyses: Evidence for trait-specific polygenic variance structure.

Genotype-stratified variance of a quantitative trait could differ in the presence of gene-gene or gene-environment interactions. Genetic markers associated with phenotypic variance are thus considered promising candidates for follow-up interaction or joint location-scale analyses. However, as in studies of main effects, the X-chromosome is routinely excluded from "whole-genome" scans due to analytical challenges. Specifically, as males carry only one copy of the X-chromosome, the inherent sex-genotype dependency could bias the trait-genotype association, through sexual dimorphism in quantitative traits with sex-specific means or variances. Here we investigate phenotypic variance heterogeneity associated with X-chromosome single nucleotide polymorphisms (SNPs) and propose valid and powerful strategies. Among those, a generalized Levene's test has adequate power and remains robust to sexual dimorphism. An alternative approach is a sex-stratified analysis but at the cost of slightly reduced power and modeling flexibility. We applied both methods to an Estonian study of gene expression quantitative trait loci (eQTL; n = 841), and two complex trait studies of height, hip, and waist circumferences, and body mass index from Multi-Ethnic Study of Atherosclerosis (MESA; n = 2,073) and UK Biobank (UKB; n = 327,393). Consistent with previous eQTL findings on mean, we found some but no conclusive evidence for cis regulators being enriched for variance association. SNP rs2681646 is associated with variance of waist circumference (p = 9.5E-07) at X-chromosome-wide significance in UKB, with a suggestive female-specific effect in MESA (p = 0.048). Collectively, an enrichment analysis using permutated UKB (p < 0.1) and MESA (p < 0.01) datasets, suggests a possible polygenic structure for the variance of human height.