Objective: To investigate the prevalence of undernutrition and its associated factors among left behind and non left behind primary and secondary school students in the Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES) areas of central and western China, so as to provide evidence for improving the nutritional status of children and adolescents. Methods: A survey was conducted among 123 782 students selected by random cluster sampling method in grades 3-9 from NIPRCES in central (Hebei, Shanxi, Heilongjiang, Jilin, Anhui, Jiangxi, Henan, Hunan, Hubei, and Hainan) and western (Gansu, Guangxi, Inner Mongolia, Ningxia, Tibet, Shaanxi, Guizhou, Sichuan, Xinjiang, the Xinjiang Production and Construction Corps, Yunnan, Qinghai, and Chongqing) China in 2023. Anthropometric measurements and questionnaires were used to assess nutritional and dietary status. The prevalence of undernutrition was compared between left behind and non left behind students by Chi square test, and associated factors were analyzed by three level Logistic mixed effects model. Results: The prevalence of undernutrition was 8.5% (4 326) in left behind students and 8.1% (5 905) in non left behind students. Three level Logistic mixed effect model analysis showed that whether left behind or non left behind, the undernutrition rates of primary and secondary students in western regions were higher than those of students in central regions [ OR (95% CI )=1.72(1.57-1.87),2.25(2.07- 2.43 )]; the undernutrition risk was lower for those whose fathers had a cultural level of high school or above [ OR (95% CI )=0.69(0.62-0.77),0.90(0.82-0.98)] or junior high school [ OR (95% CI )=0.72(0.66-0.79),0.92(0.85-0.99)] compared to those with primary school or below; picky eating or selective eating increased the risk of undernutrition [ OR (95% CI )=2.36(2.07-2.68),2.28(2.04-2.55)], and primary and secondary school students without nutritional content in health education classes had higher rates of undernutrition [ OR (95% CI )=1.12(1.03-1.23),1.09(1.01-1.17)](all P <0.05). Conclusion The prevalence of undernutrition is slightly higher in left behind primary and secondary students than in non left behind primary and secondary students in central and western NIPRCES areas, with variations across different characteristics.

Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.

The α7 nicotinic acetylcholine receptor (α7 nAChR) is a ligand-gated ion channel characterized by high Ca²⁺ permeability, rapid activation, and rapid desensitization. It is widely expressed in the nervous system and various non-neuronal cell types. α7 nAChR is involved in regulating neuronal excitability, synaptic transmission and plasticity, cognitive function, and inflammatory responses. These properties have made α7 nAChR a potential therapeutic target for neuropsychiatric and inflammatory diseases. In recent years, advances in cryo-electron microscopy have provided structural insights into α7 nAChR gating, ligand recognition, allosteric modulation, and allosteric activation. The receptor mainly undergoes transitions among resting, open, and desensitized states. Recent structural studies have further revealed asymmetric conformational changes and multiple intermediate states during receptor activation and recovery from desensitization. Conformational rearrangements in the extracellular domain-transmembrane domain coupling region and the pore-forming M2 helices are closely associated with channel opening and desensitization. However, structural characterization of the α7 nAChR gating cycle still largely depends on pharmacological stabilization. Open-state structures have been resolved in the presence of PNU-120596 or GAT107, whereas a high-resolution structure of the open state induced by acetylcholine alone remains to be determined. These physiological roles underpin the involvement of α7 nAChR in multiple disease processes. In the hippocampus, α7 nAChR regulates local neuronal circuits, theta oscillations, synaptic transmission, and synaptic plasticity, thereby contributing to learning, memory, attention, and other cognitive processes. In macrophages, microglia, and other immune-related cells, α7 nAChR activation regulates inflammatory responses and oxidative stress. These effects involve several signaling pathways, including Janus kinase 2 (JAK2)/STAT3, phosphoinositide 3-kinase (PI3K)/AKT, and NF-κB signaling, as well as regulation of the NLRP3 inflammasome and IL-1β production. Such anti-inflammatory effects may also contribute to α7 nAChR-mediated neuroprotection. Although several compounds targeting α7 nAChR have entered clinical studies, no α7 nAChR-selective drug has been approved for clinical use. Limited clinical translation may be related to rapid receptor desensitization, inconsistent efficacy across clinical studies, insufficient or variable target engagement, patient heterogeneity, and clinical endpoint selection. TC-5619 showed promising effects on cognitive impairment and negative symptoms in an early exploratory study of schizophrenia, but these effects were not confirmed in a subsequent, larger phase II trial. Encenicline (EVP-6124) also showed cognitive improvement in early studies, whereas two global phase III trials in schizophrenia failed to meet their co-primary cognitive and functional endpoints. Pharmacological strategies targeting α7 nAChR have expanded from orthosteric agonists to positive allosteric modulators (PAMs) and allosteric agonist-positive allosteric modulators (ago-PAMs). Orthosteric agonists directly activate the receptor by binding to the orthosteric site, but their effects are limited by rapid receptor desensitization. Type I PAMs mainly enhance agonist-evoked responses with relatively small effects on desensitization, whereas type II PAMs markedly potentiate receptor responses and reduce or delay desensitization. Ago-PAMs such as GAT107 can directly activate α7 nAChR through an allosteric mechanism while also potentiating responses to orthosteric agonists. Together, these findings have broadened the pharmacological approaches to α7 nAChR regulation. In summary, future drug development should focus on precise regulation of α7 nAChR according to receptor structure and disease mechanisms, rather than simply enhancing receptor activation. Further studies are needed to clarify how candidate ligands affect receptor gating, conformational transitions, recovery from desensitization, and downstream signaling. Pharmacological differences between neuronal and non-neuronal α7 nAChRs, between homomeric α7 and heteromeric α7β2 receptors, and between α7 nAChR and other nAChR subtypes also require further investigation. Integrating structure prediction, artificial intelligence-assisted virtual screening, molecular docking, molecular dynamics simulations, and electrophysiological validation may facilitate the discovery and optimization of new α7 nAChR modulators.

Purpose: The study aimed to comprehensively analyze testosterone and precursor concentrations in the testicular interstitial fluid (TIF) of men with azoospermia, exploring their significance in the testicular microenvironment and their correlation with testicular sperm retrieval outcomes. Materials and Methods: We analyzed 37 TIF samples, including 5 from men with obstructive azoospermia (OA) and 32 from men with non-obstructive azoospermia (NOA). Liquid chromatography with tandem mass spectrometry quantified testosterone and precursor levels. Comparative assessments of the outcomes of testicular sperm retrieval were performed between the OA and NOA groups as well as among men with NOA. Results: Men with NOA who had not undergone hormone treatment exhibited significantly higher intratesticular concentrations of testosterone (median 1,528.1 vs. 207.5 ng/mL), androstenedione (median 10.6 vs. 1.9 ng/mL), and 17-OH progesterone (median 13.0 vs. 1.8 ng/mL) than men diagnosed with OA. Notably, in the subgroup of patients with NOA subjected to medical treatment, men with successful sperm retrieval had significantly reduced levels of androstenedione (median androstenedione 5.7 vs. 18.5 ng/mL, p=0.004). Upon a more detailed analysis of these men who underwent hormone manipulation treatment, the testosterone/androstenedione ratio (indicative of HSD17B3 enzyme activity) was markedly increased in men with successful sperm retrieval (median: 365.8 vs. 165.0, p=0.008) compared with individuals with NOA who had unsuccessful sperm recovery. Furthermore, within the subset of men with NOA who did not undergo medical treatment before microdissection testicular sperm extraction but achieved successful sperm retrieval, the ratio of 17-OH progesterone/progesterone (indicative of CYP17A1 activity) was substantially higher. Conclusions The study suggests distinct testosterone biosynthesis pathways in men with compromised spermatogenesis and those with normal spermatogenesis. Among NOA men with successful retrieval after hormone optimization therapy, there was decreased androstenedione and increased HSD17B3 enzyme activity. These findings have diagnostic and therapeutic implications for the future.

Purpose: The study aimed to comprehensively analyze testosterone and precursor concentrations in the testicular interstitial fluid (TIF) of men with azoospermia, exploring their significance in the testicular microenvironment and their correlation with testicular sperm retrieval outcomes. Materials and Methods: We analyzed 37 TIF samples, including 5 from men with obstructive azoospermia (OA) and 32 from men with non-obstructive azoospermia (NOA). Liquid chromatography with tandem mass spectrometry quantified testosterone and precursor levels. Comparative assessments of the outcomes of testicular sperm retrieval were performed between the OA and NOA groups as well as among men with NOA. Results: Men with NOA who had not undergone hormone treatment exhibited significantly higher intratesticular concentrations of testosterone (median 1,528.1 vs. 207.5 ng/mL), androstenedione (median 10.6 vs. 1.9 ng/mL), and 17-OH progesterone (median 13.0 vs. 1.8 ng/mL) than men diagnosed with OA. Notably, in the subgroup of patients with NOA subjected to medical treatment, men with successful sperm retrieval had significantly reduced levels of androstenedione (median androstenedione 5.7 vs. 18.5 ng/mL, p=0.004). Upon a more detailed analysis of these men who underwent hormone manipulation treatment, the testosterone/androstenedione ratio (indicative of HSD17B3 enzyme activity) was markedly increased in men with successful sperm retrieval (median: 365.8 vs. 165.0, p=0.008) compared with individuals with NOA who had unsuccessful sperm recovery. Furthermore, within the subset of men with NOA who did not undergo medical treatment before microdissection testicular sperm extraction but achieved successful sperm retrieval, the ratio of 17-OH progesterone/progesterone (indicative of CYP17A1 activity) was substantially higher. Conclusions The study suggests distinct testosterone biosynthesis pathways in men with compromised spermatogenesis and those with normal spermatogenesis. Among NOA men with successful retrieval after hormone optimization therapy, there was decreased androstenedione and increased HSD17B3 enzyme activity. These findings have diagnostic and therapeutic implications for the future.

Objective: To understand the prevalence and related factors of depressive symptoms among primary and secondary school students in the in depth monitoring counties of China s Rural Compulsory Education Nutrition Improvement Program, so as to provide a basis for prevention and psychological intervention of depressive symptoms among children and adolescents in rural areas. Methods: In November 2022, a stratified random sampling method was adopted to collect height and weight data, basic personal and family information of 7 949 primary and secondary school students from grade three to grade nine through physical measurements and questionnaires in 56 key monitoring schools implementing the Student Nutrition Improvement Program in 7 in depth monitoring counties (Jalaid Banner in Inner Mongolia, Jinzhai County in Anhui, Mao Xian in Sichuan, Tiandeng County in Guangxi, Mian County in Shaanxi, Zhaozhou County in Heilongjiang and Youxi County in Fujian), and to obtain the information related to their depressive symptoms through the self assessment questionnaire on depression. Multivariate Logistic regression analysis was conducted to analyze the prevalence of depressive symptoms among primary and secondary school students, as well as their related factors. Results: The detection rate of depressive symptoms among primary and secondary school students in the in depth monitored counties was 23.5%. Logistic regression analysis showed that the probability of detecting depressive symptoms was higher among female students, middle school students, students whose video screen duration per day was >2 h, and students whose parents marital status was divorced or widowed ( OR =1.40, 1.64, 1.60, 1.24), and students whose sleep duration reached the recommended standard, whose parents usually accompanied them daily for time was 60-<120 min and ≥120 min, and students whose mothers literacy level was middle school graduation had lower probability of detecting depressive symptoms ( OR =0.85, 0.84, 0.71, 0.76) ( P < 0.05 ). Conclusion The detection rate of depressive symptoms among students in the in depth monitoring area is high, and targeted interventions need to be developed for students to reduce the risk of mental health problems.

BackgroundPatients with depressive disorder often exhibit impaired decision-making functions. However， the relationship between decision-making abilities and depressive and anxiety symptoms in these patients remains unclear. ObjectiveTo explore the characteristics of decision-making behavior in patients with depressive disorder， and to analyze its relationship with clinical symptoms. MethodsA total of 48 patients diagnosed with depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders， fourth edition （DSM-IV） were recruited from the Department of Psychosomatic Medicine of the Affiliated Hospital of Southwest Medical University from October 2020 to May 2023. Concurrently， 52 healthy individuals matched for age and gender were recruited from Luzhou as the control group. Beck Depression Inventory （BDI） and Beck Anxiety Inventory （BAI） were used for assessment， and decision-making behavior was evaluated using Probabilistic Reversal Learning （PRL） task. Indicators assessed included the number of trials to criterion， perseverative errors， win-stay rate and lose-shift rate. Spearman correlation analysis was used to assess the correlation between BDI and BAI scores and PRL task indicators. ResultsThe depression group showed a significantly higher lose-shift rate compared with the control group （t=3.684， P<0.01）. There were no statistically significant differences between two groups in trials to criterion， perseverative errors and win-stay rate （t=0.329， 0.132， 0.609， P>0.05）. In depression group， BDI and BAI scores were positively correlated with the win-stay rate（r=0.450， 0.398， P<0.01）. ConclusionPatients with depressive disorder are more likely to change their decision-making strategies following negative outcomes. Furthermore， the severity of depressive and anxiety symptoms is associated with a greater propensity to maintain existing decisions after receiving positive feedback. ［Funded by 2019 Joint Project of Luzhou Science and Technology Bureau-Southwest Medical University （number， 2019LZXNYDJ39］

Objective To analyze the relationships between color Doppler ultrasound parameters and insulin sensitivity index(ISI)and clinical efficacy in rats with polycystic ovary syndrome(PCOS)combined with hyperinsulinemia(HI).Methods A total of 140 3-week-old female SD SPF-grade rats were divided randomly into a PCOS without HI model(control group,n=70)and a PCOS combined with HI model(study group,n=70).After successful modeling,we used color Doppler ultrasound to detect the physical indicators,hemodynamic indicators,and ultrasound features of rat ovaries,and draw venous blood to evaluate ISI.Rats in the study group were treated with metformin by intragastric administration.The color Doppler ultrasound parameters of the good-effect and the poor-effect group were compared and a receiver operating characteristic curve(ROC)was drawn to analyze the value of the color Doppler ultrasound parameters for evaluating the curative effect of metformin in rats with PCOS combined with HI.Results The total ovarian area(TA),ovarian volume(OV),ovarian interstitial area(SA),vascularization index(VI),blood flow index(FI),fasting insulin(FINS),and fasting blood glucose(BFG)of the research group were all greater than those of the control group,while the resistance index,pulsatility index and ISI were observed significantly lower compared with contrast,there were obvious difference(P＜0.05).The color Doppler ultrasound parameters TA and SA were negatively correlated with ISI(r=-0.501,r=-0.492,respectively,P＜0.05),and ovarian RI and PI were positively correlated with ISI(r=0.504,r=0.485,respectively,P＜0.05).TA,OV,SA,VI,FI,VFI,PSV,PDV,low-density lipoprotein cholesterol,FPG,FINS,LH,and FSH were all significantly lower while RI and PI were significantly higher in the good-curative-effect group compared with the poor-curative-effect group(all P＜0.05).According to ROC curve analysis,the sensitivity and specificity of color Doppler ultrasound parameters combined with clinical efficacy were 90.9％and 90.2％,respectively,and the area under the curve(AUC)was 0.901.Conclusions Color Doppler ultrasound parameters are closely related to ISI and therapeutic efficacy in rats with PCOS combined with HI,and may thus predict clinical efficacy in patients with these conditions.

BackgroundWith the rapid development of the networking technologies， internet addiction has increasingly become a serious mental health issue. Previous studies have revealed the link between childhood trauma and internet addiction， while the mediating role of perceived stress in this link is not yet clear. ObjectiveTo investigate the role of medical students' perceived stress in the relationship between childhood trauma and internet addiction， so as to provide references for the intervention of internet addiction. MethodsFrom February to March 2023， a random sampling technique was used to select 1 232 undergraduate students from the School of Clinical Medical Sciences of Southwest Medical University as research subjects. The Childhood Trauma Questionnaire-Short Form （CTQ-SF）， Perceived Stress Scale （PSS）， Internet Gaming Disorder Scale （IGDS）， and Bergen Social Media Addiction Scale （BSMAS） were used for assessment. Pearson's correlation coefficients were calculated. The mediation effect of perceived stress in the relationship between childhood trauma and internet addiction was tested using Model 4 in the SPSS Process 4.1， and Bootstrapping procedure involving 5 000 replicates was employed to confirm the statistical significance. ResultsA total of 1 016 （82.47%） valid completed questionnaires were gathered. The CTQ-SF scores of medical students were positively correlated with PSS scores， IGD scores， and BSMAS scores （r=0.583， 0.474， 0.465， P<0.01）. PSS scores were positively correlated with IGD scores and BSMAS scores （r=0.369， 0.479， P<0.01）. Childhood trauma in medical students was found to positively predict perceived stress （β=0.191， P<0.01）， social media addiction （β=0.160， P<0.01）， and internet gaming disorder （β=0.106， P<0.01）. Perceived stress played a significant mediating role in the relationship between childhood trauma and internet gaming disorder， indirect effect value was 0.018 （95% CI： 0.009~0.027）， accounting for 16.98%. Perceived stress also exhibited a significant mediating role in the relationship between childhood trauma and social media addiction， indirect effect value was 0.063 （95% CI： 0.048~0.079）， accounting for 39.38%. ConclusionChildhood trauma in medical students may affect internet gaming disorder and social media addiction through perceived stress. ［Funded by 2022 Annual Research Project of Sichuan Applied Psychology Research Center，（number，CSXL-22102）］

Objective: To analyze the features of unhealthy lifestyle patterns among primary and secondary school students in the nutrition improvement program for rural compulsory education students (NIPRCES) areas in China in 2021 and 2023, so as to provide data support for lifestyle promotion and healthy development among primary and secondary school students. Methods: Adopting a cluster random sampling method, data on primary and secondary students aged 7-15 years from nutrition and health surveillance of China NIPRCES in 2021 and 2023 were collected. The prevalence of unhealthy lifestyles among primary and secondary students such as physical inactivity, outdoor inactivity, excessive screen time, and sleep deprivation by gender, school section, urban/rural, and region were analyzed. The reporting rates of the above indicators among primary and secondary students were compared by Chi-square test. Results: In 2021 and 2023, the rates of moderate to vigorous physical inactivity among primary and secondary school students were 79.2% and 80.4%, the rates of outdoor inactivity were 42.8% and 49.3%, the rates of excessive video time were 2.6% and 2.9%, the rates of sleep deprivation were 32.9% and 22.6%, and the differences were statistically significant( χ 2=51.86,1 071.48,18.36,3 296.99, P <0.05). In 2023, the rate of outdoor inactivity for primary and secondary students increased by 6.5 percentage points compared with 2021, and the rate of sleep deprivation decreased by 10.3 percentage points compared with that in 2021. In 2021 and 2023, the reporting rates of moderate to vigorous physical inactivity, outdoor inactivity, and sleep deprivation among girls and junior high school students were higher than those among boys ( χ 2=174.41,180.11; 175.75, 85.46 ;92.22,151.35) and elementary school students ( χ 2=136.64,5.75; 40.55,4.71;162.80,3 291.61); the reporting rates of moderate to vigorous physical inactivity( χ 2=194.43,118.60) and sleep deprivation ( χ 2=969.66,983.72) among urban students were higher than those among rural students; the reporting rates of excessive video time for boys and junior high school students were higher than those for girls ( χ 2=103.62,84.85) and elementary school students ( χ 2=810.09,626.51)( P <0.05). From a regional distribution perspective, the reporting rates of moderato to vigorous physical inactivity, outdoor inactivity, and excessive video time among primary and seconday school students in the central and western regions were lower than those in the eastern region ( χ 2= 663.44,302.78; 356.97,82.10;50.89,81.83) ( P <0.05). Conclusions Unhealthy lifestyles remain prevalent among primary and secondary students in NIPRCES areas of China. These findings underscore the need to strengthen policy implementation for promoting healthy lifestyles among primary and secondary school students.