Objective: To explore a simple, effective, and safe method for excluding false positives and identifying infections by comprehensively evaluating blood donors with reactive HIV screening results, thereby providing a basis for developing management strategies for such donors. Methods: HIV testing data of blood donors from our laboratory from January 2022 to December 2024 were collected. The results of ELISA and nucleic acid testing (NAT) were combined with confirmatory results from the CDC and analyzed. Results: A total of 605 929 samples were tested for HIV over the three-year period, with 682 reactive samples (reactive rate: 11.25 per 10 000). All were sent to the CDC for Western blot (WB) confirmation, resulting in 53 confirmed positives ((confirmed positive rate: 7.77%). Among these, 619 samples showed isolated HIV Ag&Ab reactivity with non-reactive NAT (HIV Ag&Ab+-&HIV RNA or NAT NR), with a confirmed infection rate of 0%; 9 samples showed dual HIV Ag&Ab reactivity with non-reactive NAT (HIV Ag&Ab++&HIV RNA NR or NAT NR), also with 0% confirmed infection; 52 samples showed dual HIV Ag&Ab reactivity and reactive NAT (HIV Ag&Ab++&HIV RNA R or NAT R), all confirmed as positive (100% infection rate); and 2 HIV Ag&Ab dual-reactive samples without NAT detection were also confirmed infected (100%). For all four HIV Ag&Ab assays, the S/CO values in the true positive group with dual reactivity were significantly higher than those in the false-positive groups (P<0.05). The S/CO distributions for both single-reactive false positives and dual-reactive false positives were narrow, with the upper box (Q3, 75th percentile) below optimal cutoff values in all cases (The optimal cutoff values for the four reagents were 5.00, 11.67, 8.50, and 20.90, respectively). Conclusion: Blood donors with positive NAT results in HIV blood screening are permanently deferred. Donors with dual positive HIV Ag&Ab but negative NAT results are classified and managed based on the S/CO values of HIV Ag&Ab and the optimal screening thresholds. Donors with single positive HIV Ag&Ab but negative NAT results are placed under evaluation status and retain their eligibility to donate blood. Optimizing the management measures for blood donors and establishing a scientific stratified management and assessment mechanism can effectively maintain the stability of the blood donor team.

OBJECTIVE To investigate the effects of baicalin （BC） on insulin resistance in rats with gestational diabetes mellitus （GDM） and its underlying mechanism based on the adenosine monophosphate-activated protein kinase （AMPK）/suppressor of variegation 3-9 homolog 1 （SUV39H1）/histone H3 lysine 9 trimethylation （H3K9me3） axis. METHODS A GDM rat model was established by a combination of a high-fat diet and streptozotocin injection. The successfully modeled rats were divided into the GDM group， BC low-dose group， BC high-dose group， and high-dose of BC+AMPK inhibitor （Compound C） group， with 10 rats in each group. Another 10 pregnant rats fed a normal diet served as the control group. Rats in each group were given corresponding drugs/normal saline intragastrically and/or intraperitoneally， once daily for 2 consecutive weeks. After the last administration， the levels of fasting blood glucose （FBG）， pancreatic function indexes [fasting insulin （FINS）， homeostasis model assessment of insulin resistance （HOMA-IR）， insulin sensitivity index （ISI）]， blood lipid indexes （total cholesterol， triglyceride， low-density lipoprotein cholesterol）， liver function indexes （alanine transferase， aspartate transferase， alkaline phosphatase）， inflammatory indicators （C-reactive protein， interleukin-1β， interleukin-6）， metabolic regulatory protein [complement-C1q/tumor necrosis factor-related protein 3 （CTRP3）]， insulin sensitivity related factors [glucose transporter 4 （GLUT4）， adiponectin]， and oxidative stress indicators [superoxide dismutase （SOD）， catalase （CAT）， malondialdehyde （MDA）] were measured. Pathological changes in liver tissue were observed， and the expressions of proteins related to the AMPK/SUV39H1/H3K9me3 axis in liver tissue were detected. RESULTS Compared with the GDM group， rats in the BC low- and high-dose groups showed varying degrees of improvement in pathological changes such as disordered cell arrangement， vacuolar degeneration， lipid deposition， and inflammatory cell infiltration in liver tissue. Their FBG and FINS levels， HOMA-IR， the levels of blood lipid indexes， liver function indexes， inflammatory indicators and MDA， and the expressions of SUV39H1 and H3K9me3 were significantly decreased or down-regulated， while metabolic regulatory protein， insulin sensitivity-related factors and AMPK protein phosphorylation levels were significantly increased （ P ＜0.05）. The improvement was more significant in the BC high-dose group （ P ＜0.05）. Compound C could significantly reverse the ameliorative effects of high-dose BC on the above quantitative indicators （ P ＜0.05）. CONCLUSIONS BC can significantly reduce oxidative stress and inflammatory responses， increase serum levels of CTRP3， GLUT4 and adiponectin， thereby improving insulin resistance in GDM rats. These effects may be related to the activation of AMPK and inhibition of SUV39H1-mediated H3K9me3 modification.

Objective: To analyze the association between insufficient sleep and score of depressive symptoms among junior and senior high school students, so as to provide a scientific reference for targeted early intervention measures of adolescents depressive symptoms. Methods: From September to November 2023, a stratified cluster random sampling method was used to select 96 080 junior and senior high school students from 409 schools in 113 districts and counties in Shaanxi Province. A questionnaire survey was conducted using the 2023 Shaanxi Provincial Common Student Diseases and Health Influencing Factors Survey Form, and their height and weight were measured. Propensity score (PS) matched (1∶1) analysis was used to match participants with insufficient sleep to those sufficient sleep students. Through the gradual correction of the confounders, three multilevel linear models were established to analyze the association between insufficient sleep and depressive symptoms score, and subgroup analysis was conducted afterward. Results: A total of 70 135 (73.00%) students had insufficient sleep. After PS matching, 25 894 pairs were matched. Before PS matching, after adjusting for gender, educational stage, region, adolescent characteristics, boarding status, smoking, alcohol consumption, outdoor activities and body mass index grouping, linear regression analysis results showed that compared with students who got adequate sleep, students who lacked sleep had an increase of 1.39 scores ( B=1.39, 95%CI =1.28-1.51) in depressive symptoms; after PS matching, students with insufficient sleep got an increase of 1.32 scores ( B=1.32, 95%CI =1.17- 1.45 ) in depressive symptoms score compared with those who had adequate sleep (both P <0.05). Conclusions The insufficient sleep is associated with the increase of the depressive symptoms score of junior and senior high school students. It is recommended that junior and senior high school students should keep a good sleeping habit, so as to reduce the prevalence of depressive symptoms.

Objective To explore the correlation between lymph node metastasis and clinicopathological features of lung adenocarcinoma with diameter≤3 cm. Methods The clinicopathologic data of the patients with lung adenocarcinoma≤3 cm in diameter were retrospectively analyzed. The relationship between lymph node metastasis and age, gender, smoking history, pathological subtype, tumor diameter, pleural invasion, vascular invasion and other factors was analyzed. The risk factors of lymph node metastasis were analyzed by univariate and multivariate logistic regression. Results Finally 1 718 patients were collected, including 697 males and 1 021 females with an average age of (58.89±9.85) years. The total lymph node metastasis rate was 12.9%, among whom 452 patients of adenocarcinoma in situ and minimally invasive adenocarcinoma did not have lymph node metastasis, and the lymph node metastasis rate of invasive lung adenocarcinoma was 17.5%. Multivariate analysis showed that tumor diameter, micropapillary subtype, solid subtype, micropapillary component, solid component, vascular invasion and pleural invasion were independent risk factors for lymph node metastasis of invasive lung adenocarcinoma with diameter≤3 cm (P<0.05). While age, lepidic subtype and lepidic component were independent protective factors for lymph node metastasis (P<0.05). Conclusion Clinicopathological features can help predict lymph node metastasis of lung adenocarcinoma with diameter≤3 cm.

[摘 要] 目的：开发新型溶瘤呼肠孤病毒（Reo）递送系统，以克服中和抗体对Reo的中和作用并提升其肿瘤靶向性。方法：通过切向流过滤联合超高速离心法制备自然杀伤细胞外泌体（NKexo），叶酸（FA）修饰后采用挤压法包载Reo，构建FA-NKexo-Reo递送系统；通过透射电镜（TEM）、纳米粒径分析、蛋白质印迹（WB）法、核磁共振氢谱及流式细胞术等技术表征其理化性质；采用CCK-8、流式细胞术、Transwell实验及激光共聚焦显微镜评估FA-NKexo-Reo递送系统体外细胞毒性及细胞摄取能力；通过人卵巢癌裸鼠皮下移植瘤模型评价FA-NKexo-Reo的肿瘤靶向性、疗效及安全性。结果：FA-NKexo-Reo粒径为（94.0 ± 28.5）nm，Zeta电位为（-21.26 ± 1.57）mV，包封率达（49.7 ± 15.6）%；在中和抗体的存在下，FA-NKexo-Reo对卵巢癌细胞SKOV3和A2780仍可表现出显著的细胞毒性（P < 0.01）；荷瘤鼠活体成像显示FA-NKexo-Reo肿瘤靶向性显著优于NKexo组，肿瘤抑制率提升60%（P < 0.001）。结论：成功制备FA-NKexo-Reo递送系统，在中和抗体的存在下，FA-NKexo-Reo可保护并靶向递送Reo到高表达叶酸受体的卵巢癌细胞，从而增强Reo的抗肿瘤作用。

[摘 要] 目的：探讨异位表达血红蛋白亚基（HBA/HBB）对缺氧条件下嵌合抗原受体T细胞（CAR-T细胞）功能障碍的改善作用及其对肿瘤细胞的杀伤效应。方法：全基因合成技术合成靶向HER2的CAR序列，构建共表达HBA或HBB的CAR慢病毒载体，包装慢病毒后感染人原代T淋巴细胞，制备异位表达HBA/HBB的CAR-T细胞，命名为HBA CAR-T和HBB CAR-T。采用缺氧探针检测小鼠实体瘤缺氧状态。通过流式细胞术检测瘤内CAR-T细胞占比、异位表达血红蛋白亚基的CAR-T细胞阳性率及CAR-T细胞的活性氧、凋亡水平。WB法检测HBA CAR-T和HBB CAR-T内相关血红蛋白亚基表达情况，采用细胞计数板计数检测细胞增殖水平，通过萤光素酶报告基因法检测CAR-T细胞对肿瘤细胞的杀伤能力，qPCR检测CAR-T细胞中缺氧诱导因子-1α（HIF-1α）表达水平，利用MitoXpress Intra试剂盒检测CAR-T细胞内氧气含量。结果：不同细胞构建的实体瘤模型均存在明显缺氧情况，且CAR-T细胞浸润水平与缺氧程度呈显著负相关（P < 0.000 1）。HBA CAR-T与HBB CAR-T构建成功（阳性率 > 60%），相应血红蛋白亚基可稳定表达。缺氧环境下HBA CAR-T和HBB CAR-T的ROS水平、凋亡水平显著下降，增殖、对肿瘤细胞的体外杀伤能力显著强于传统CAR-T细胞（均P < 0.05）。HBA CAR-T与HBB CAR-T内HIF-1α表达降低（均P < 0.001），且缺氧程度显著降低（均P < 0.001）。结论：异位表达血红蛋白亚基可改善缺氧条件下CAR-T细胞功能障碍并增强其对肿瘤细胞的体外杀伤作用。

[摘 要] 目的：探究蟾毒灵（Buf）对卵巢癌细胞A2780和SKOV3的毒性作用及其机制，评估其与顺铂（DDP）联合应用的协同毒性。方法：常规培养A2780和SKOV3细胞。用CCK-8法、克隆形成实验检测Buf对A2780和SKOV3细胞增殖的影响及半数抑制浓度（IC50）。用不同浓度的Buf处理细胞，显微镜下观察细胞形态变化，比色法检测乳酸脱氢酶（LDH）释放水平，流式细胞术分析检测Annexin Ⅴ+PI+细胞比例，qPCR和WB法检测细胞焦亡相关分子mRNA及蛋白表达水平，通过小干扰RNA敲减A2780和SKOV3细胞中的GSDMD并进行后续功能实验进行验证。通过SynergyFinder分析Buf与DDP对于杀伤A2780和SKOV3细胞的协同效应，并通过流式细胞术、qPCR、WB进行机制探索，进一步利用流式细胞术检测Buf与DDP联用对DDP耐药A2780和SKOV3细胞的影响。结果：与对照组相比，Buf显著抑制卵巢癌细胞增殖及迁移能力（均P < 0.05），诱导LDH释放和细胞焦亡（均P < 0.05），上调核苷酸结合寡聚化结构样受体热蛋白结构域相关蛋白3（NLRP3）、半胱氨酸天冬氨酸蛋白水解酶1（CASP1）、gasdermin家族成员D（GSDMD）、白细胞介素-1β（IL-1β）及IL-18的mRNA及蛋白的表达（均P < 0.05），Buf与DDP联用具有协同抑制A2780和SKOV3细胞增殖的作用，并可进一步增强DDP耐药的A2780和SKOV3细胞对DDP的敏感性（P < 0.01或P < 0.001）。结论：Buf可通过激活NLRP3/CASP1/GSDMD信号通路诱导A2780和SKOV3细胞焦亡，并增强A2780和SKOV3细胞及DDP耐药A2780和SKOV3细胞对DDP的敏感性。

Objective: To investigate the association between sleep duration and depressive symptoms in children and adolescents, so as to provide scientific evidence for promoting mental health and preventing depression among relevant populations. Methods: A total of 2 192 children and adolescents aged 10-17 years with complete data from the 2018 China Family Panel Studies Database were included. Eight item Center for Epidemiologic Studies Depressive Scale(CES-D8) was used to assess participants depressive levels, and sleep duration was assessed via questionnaire. Multivariate Logistic regression model was used to analyze the association between different sleep duration categories and depressive symptom occurrence among children and adolescents. A restricted cubic spline(RCS) model analyzed the dose response relationship between sleep duration and the risk of depressive symptoms occurrence and segmented Logistic regression models to identify dose response effects. Results: Among the surveyed children and adolescents, 524(23.91%) exhibited depressive symptoms. Compared to those with sufficient sleep, children aged 10-12 years had a higher risk of depressive symptoms on average per day( OR =1.66, 95% CI =1.19-2.33) and during weekdays( OR =1.76, 95% CI =1.26-2.46), as well as in adolescents aged 13-17 years on a daily basis( OR =1.40，95% CI =1.06-1.85) and during weekdays( OR = 1.48，95% CI =1.12-1.95), and excessive sleep in adolescents on rest days was also significantly associated with higher risk of depressive symptoms( OR =1.65，95% CI =1.11-2.43)(all P <0.05). RCS analysis results indicate that children s sleep duration exhibits a linear negative correlation with the risk of depressive symptoms(all P nonlinear >0.05), while adolescents sleep duration showed a U shaped association with depressive symptoms(all P nonlinear <0.05) on a daily basis, during weekdays and weekends, with potential threshold effects at 10.00, 9.88, and 9.60 hours, respectively. Conclusions Sleep duration among children and adolescents is associated with depressive symptoms, with notable age related differeneces. It is recommended to develop targeted age specific interventions to reduce the risk of depressive symptoms in children and adolescents.

Objective: To investigate the association of the joint effect of body fat levels and dyslipidemia with cardiovascular structural abnormalities in children, so as to provide a scientific reference for the early prevention of cardiovascular damage. Methods: Based on the data from the second follow up (October 2021 to January 2022) of the Huantai Children Cardiovascular Health Follow up Cohort, 1 308 children with complete data were included. The fat mass percentage (FMP), fat mass index (FMI), subcutaneous fat mass (SFM) and visceral fat mass (VFM), left ventricular mass index (LVMI), relative wall thickness (RWT), thickening of carotid intima-media thickening (cIMT) , left ventricular hypertrophy (LVH) and left ventricular geometric remodeling (LVG), triglyceride (TG), total cholesterol (TC) ,high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were obtained. Multivariable Logistic regression model was used to analyze the associations of FMP, FMI, SFM and VFM with thickening of cIMT, LVH and LVG. The joint effects of these body fat indicators and dyslipidemia on the aforementioned cardiovascular outcomes were further explored. Restricted cubic spline model was used to examine the dose response relationships between body fat levels and cardiovascular structural abnormalities. Results: Elevated body fat levels were significantly associated with an increased risk of cardiovascular structural abnormalities, exhibiting J shaped dose response relationships (all P <0.05). Compared with the group with normal body fat and normolipidemia, the risks of thickening of cIMT, LVH, and LVG in the group with elevated FMP combined with dyslipidemia were higher[ OR (95% CI )=11.70 (6.49-21.27), 5.53 (2.97-10.17), 2.33 (1.30-4.05)]; in the group with elevated FMI combined with dyslipidemia, the corresponding risks were higher[ OR (95% CI )= 11.68 (6.43-21.38), 6.98 (3.73-12.92), 2.65 (1.50-4.61)]; in the group with elevated SFM combined with dyslipidemia, the corresponding risks were higher[ OR (95% CI )=10.55 (5.83-19.24), 5.11 (2.71-9.45), 1.99 (1.11- 3.46 )]; and in the group with elevated VFM combined with dyslipidemia, the corresponding risks were higher[ OR (95% CI )=12.44 (6.76-23.14), 6.17 ( 3.31 -11.38), 2.30 (1.30-3.99)] (all P <0.05). Sex stratified analyses showed that the risk of thickening of cIMT in the combined exposure group of all four body fat indicators and dyslipidemia was significantly higher in girls than in boys (all P <0.01). Conclusions Elevated body fat levels and dyslipidemia have a combined effect in children, collectively increasing the risk of cardiovascular structural abnormalities. Prevention of cardiovascular damage in children should focus on both adiposity management and blood lipid regulation.

ObjectiveBola-like short peptides exhibit novel self-assembly properties due to the formation of peptide dimers via hydrogen bonding interactions between their C-terminals. In this configuration, hydrophilic amino acids are distributed at both terminals, making these peptides behave similarly to Bola peptides. The electrostatic repulsive interactions arising from the hydrophilic amino acids at each terminal can be neutralized, thereby greatly promoting the lateral association of β-sheets. Consequently, assemblies with significantly larger widths are typically the dominant nanostructures for Bola-like peptides. To investigate the effect of hydrophilic amino acids on the self-assembly behavior of Bola-like peptides, the peptides Ac-RI₃-CONH₂ and Ac-HI₃-CONH₂ were designed and synthesized using the Bola-like peptide Ac-KI₃-CONH₂ as a template. Their self-assembly behavior was systematically examined. MethodsAtomic force microscopy (AFM) and transmission electron microscopy (TEM) were employed to characterize the morphology and size of the assemblies. The secondary structures of the assemblies were analyzed using circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy. Small-angle neutron scattering (SANS) was used to obtain detailed structural information at a short-length scale. Based on these experimental results, the effects of hydrophilic amino acids on the self-assembly behavior of Bola-like short peptides were systematically analyzed, and the underlying formation mechanism was explored. ResultsThe aggregation process primarily involved three steps. First, peptide dimers were formed through hydrogen bonding interactions between their C-terminals. Within these dimers, the hydrophilic amino acids K, R, and H were positioned at both terminals, enabling the peptides to self-assemble in a manner similar to Bola peptides. Next, β-sheets were formed via hydrogen bonding interactions along the peptide backbone. Finally, self-assemblies were generated through the lateral association of β-sheets. The results demonstrated that both Ac-KI₃-CONH₂ and Ac-RI₃-CONH₂ could self-assemble into double-layer nanotubes with diameters of approximately 200 nm. These nanotubes were formed by the edge fusion of helical ribbons, which initially emerged from twisted ribbons. Notably, the primary assemblies of these peptides exhibited opposite chirality: nanofibers formed by Ac-KI₃-CONH₂ displayed left-handed chirality, whereas those formed by Ac-RI₃-CONH₂ exhibited right-handed chirality. This reversal in torsional direction was primarily attributed to the different abilities of K and R to form hydrogen bonds with water. In contrast, Ac-HI₃-CONH₂ formed narrower twisted ribbons with a significantly reduced width of approximately 30 nm, which was attributed to the strong steric hindrance caused by the imidazole rings. The multilayer height of these ribbons was mainly due to the unique structure of the imidazole rings, which can function as both hydrogen bond donors and acceptors, thereby promoting aggregate growth in the vertical direction. ConclusionThe final morphology of the self-assemblies resulted from a delicate balance of various non-covalent interactions. By altering the types of hydrophilic amino acid residues in Bola-like short peptides, the relative strength of non-covalent interactions that drive assembly formation can be effectively regulated, allowing precise control over the morphology and chirality of the assemblies. This study provides a simple and effective approach for constructing diverse self-assemblies and lays a theoretical foundation for the development of functional biomaterials.