BackgroundSuicide among adolescents has become a serious public health issue， with suicidal ideation serving as a necessary precursor to suicide attempts and death. Previous research suggests that campus exclusion， depression， and psychological resilience are closely associated with the development of suicidal ideation in individuals. However， there is a lack of longitudinal research to deeply explore the relationship between each influencing factor and suicidal ideation. ObjectiveTo explore the impact of campus exclusion on suicidal ideation among adolescents， as well as the mediating role of depression and the moderating role of resilience， so as to provide references for formulating strategies for preventing and intervening in adolescent suicide. MethodsAUsing a longitudinal research design， in November 2023， 1 226 students from 21 classes （4 classes per grade in junior high school and 3 classes per grade in senior high school） from a junior high school and a senior high school in a certain area of Shandong Province were selected as the research subjects. The Ostracism Experience Scale for Adolescents （OES-A）， the Patients' Health Questionnaire Depression Scale-9 item （PHQ-9）， and the Resilience Scale for Chinese Adolescents （RSCA） were used for assessment. The PHQ-9 suicide ideation item was evaluated again three months after the baseline survey （the two suicide ideation evaluations were respectively denoted as T1 and T2 respectively. Spearman correlation analysis was used to examine the relationships among scale scores. Model 4 and model 59 in the SPSS macro program Process 4.2 were used to test the mediating effect of depression between school exclusion and suicide ideation， as well as the moderating effect of psychological resilience on the three paths. ResultsCorrelation analysis showed that OES-A score was positively correlated with PHQ-9 score and suicidal ideation item score （T2）， and PHQ-9 score was also positively correlated with suicidal ideation item score （T2） （r=0.361， 0.292， 0.508， P<0.01）. RSCA score was negatively correlated with OES-A， PHQ-9， and suicidal ideation （T2） scores （r=-0.500， -0.676， -0.459， P<0.01）. Campus exclusion positively predicted suicidal ideation （T2） and depression （β=0.081， 0.281， P<0.01）， while depression positively predicted suicidal ideation （T2） （β=0.108， P<0.01）. The mediation analysis revealed an effect size of 0.030 （95% CI： 0.019~0.043， P<0.01）， accounting for 37.35% of the total effect. Psychological resilience moderated the relationships between campus exclusion and depression， campus exclusion and suicidal ideation （T2）， and depression and suicidal ideation （T2） （β=-0.059， -0.049， -0.062， P<0.01）. ConclusionA moderated mediation model exists among campus exclusion， depression， resilience， and adolescent's suicidal ideation. Psychological resilience moderates the associations between campus exclusion， depression and suicidal ideation across all three paths. ［Funded by Beijing Municipal Health Commission Clinical Research Excellence Program， （number， BRWEP2024W072130101）；Beijing Municipal Hospital Management Center Summit Program， （number， DFL20221701）］

Objective: To evaluate the diagnostic performance of magnetic resonance spectroscopy (MRS) in discriminating fumarate hydratase-deficient (FH-d) uterine leiomyomas (ULs) from FH-preserved ULs. Materials and Methods: This study consisted of three stages, with independent cohorts recruited for each stage: 1) sample-size estimation was retrospectively performed on UL specimens (diameter ≥3 cm; age, 20–40 years) from our database with immunohistochemistry (IHC) for 2-succinocysteine (2-SC) as the reference, without genetic testing, 2) MRS sequence optimization in confirmed FH germline mutation participants with ultrasound-detected ULs (diameter ≥3 cm), without IHC analysis, and 3) prospective diagnostic test accuracy was evaluated in consecutive participants with ultrasound-detected ULs (diameter ≥3 cm;age, 20–40 years), using IHC for 2-SC for determining the FH status and subsequent genetic testing in those with positive 2-SC results to identify whether FH mutations were germline or somatic in origin. The choline and fumarate peaks in MRS were classified as positive, negative, or technical failure (TF). TFs were analyzed separately and excluded from the primary diagnostic accuracy calculations. T1-, T2-, and diffusion-weighted images were interpreted as hyperintense or hypointense. The enhancement rate and apparent diffusion coefficient were also acquired. Diagnostic performance was compared between MRS and various magnetic resonance imaging (MRI) features. Results: The optimal MRS parameters for the fumarate peak were echo time (TE) = 140 ms and an average of 256. Among the 360 prospective participants, 37 were confirmed to have FH-dULs. MRS showed positive fumarate peaks in 35 of 37 FH-dULs.After excluding six TFs, the positive fumarate peak on MRS showed 94.6% (35/37) sensitivity, 99.7% (316/317) specificity, and 99.2% (351/354) accuracy, all of which were significantly superior to those of other MRI features (P ≤ 0.002). Conclusion A positive fumarate peak on MRS may be a useful imaging biomarker for diagnosing FH-dULs.

[摘 要] 目的：探讨m6A调控因子在宫颈癌预后评估、免疫微环境特征及治疗反应中的作用，构建基于m6A调控因子的预后风险模型，并分析其与免疫浸润、药物敏感性及细胞间通信的关系。方法：基于TCGA和GEO数据库中宫颈鳞癌及腺癌（CESC）转录组数据，分析22个m6A调控因子的表达与突变情况；采用LASSO‑Cox回归构建m6A相关预后风险模型，并依据风险评分将患者分为高、低风险组。利用CIBERSORT和ESTIMATE算法评估两组免疫细胞浸润及微环境特征；通过oncoPredict预测抗肿瘤药物敏感性。整合单细胞转录组数据（E-MTAB-12305），采用CellChat分析细胞间通信网络。结果：共鉴定出12个在宫颈癌中差异表达的m6A调控因子。高风险组患者总生存期缩短（P < 0.05），免疫评分降低，且对紫杉醇、氟尿嘧啶、多柔比星等抗肿瘤药物敏感性较差（IC50较高）。单细胞分析显示宫颈癌组织中细胞间通信网络发生改变，其中T细胞与内皮/上皮细胞间的相互作用可能主要由CCL5‑ACKR1和MIF‑（CD74 + CXCR4）配体‑受体介导。在临床样本中，对关键的m6A调控因子进行mRNA和蛋白水平的验证，结果显示部分调控因子在宫颈癌组织中的表达水平高于正常宫颈组织（P < 0.05）。结论：m6A调控因子特征可有效预测宫颈癌患者预后，其风险评分与肿瘤免疫浸润、药物敏感性及细胞通信密切相关，为宫颈癌的预后分层及个体化治疗提供了新的分子依据。

ObjectiveThis study employs a special conformational engineering (CE) technology to construct an α-chymotrypsin-like active center, which includes a catalytic triad, an oxyanion hole, and a substrate-binding site, on silver nanoparticles (AgNPs), thereby creating an AgNP-based artificial hydrolase with high catalytic activity. This study provides a new approach for the design of highly efficient artificial enzymes and enzyme-mimicking. MethodsAgNPs were chosen as the scaffold to build the an α-chymotrypsin-like active center. A special CE procedure enables the designed peptide, Triad5, to adopt an α‑helical conformation on AgNPs, with the key catalytic residues located on one side of the α-helix forming a catalytic active center with a catalytic triad, an oxyanion hole, and a substrate-binding site. The CE procedure consists of three steps, including conformation induction via trifluoroethanol (TFE), conformation stabilization on AgNPs via Ag-S bonds, and TFE removal via lyophilization. Circular dichroism (CD) spectra were used to confirm the formation and stabilization of the α-helix conformation. Mutations of the key residues combined with stopped-flow kinetic experiments were used to demonstrate the indispensability of each key residue and the synergistic effects among the catalytic triad, the oxyanion hole, and the substrate-binding site. ResultsCD spectra show that the designed Triad5 alone is in random coil conformation; when conjugated on AgNPs, Triad5 still remains largely unstructured; but after the CE treatment, Triad5 adopts a typical α-helical conformation on AgNPs as designed, thus produces an AgNP-based artificial hydrolase, Silverzyme. Silverzyme exhibits extremely high hydrolytic activity towards p-nitrophenyl acetate (p-NPA), with an extremely high catalytic turnover number per active site of 3.5 s^-1, which is even higher than that of α-chymotrypsin. As a comparison, the AgNP-Triad5 conjugate without CE treatment shows much lower catalytic activity than Silverzyme, highlighting the important role of the right conformation of the active center for the catalytic activity and the power of the CE treatment. When the key residues of the catalytic triad of Silverzyme were mutated to alanine, the overall catalytic efficiency of this mutant dropped by about 2 orders of magnitude, unambiguously demonstrating the key role of the designed catalytic triad. Similarly, when the residues for the oxyanion hole were deleted, the mutant with the intact catalytic triad also showed significantly decreased catalytic activity, highlighting the indispensable role of the oxyanion hole for the catalytic activity. Unexpectedly, when both the catalytic triad and the oxyanion hole were kept intact, a slight change of the binding site also resulted in significantly decreased catalytic activity, indicating that the designed binding site is at the right position to align the substrate in the right orientation in the active center for catalytic hydrolysis. These results confirm the synergy among the catalytic triad, the oxyanion hole, and the substrate-binding site, indicating successful mimicking of the active center of α-chymotrypsin. Moreover, Silverzyme shows better thermal stability than α-chymotrypsin, and can even hydrolyze the tough non-activated ester diethyl phthalate, a priority pollutant by the United States Environmental Protection Agency (USEPA). ConclusionThis study successfully mimicked the complex catalytic active center of α-chymotrypsin using a conformational engineering strategy, and produced a highly active artificial hydrolase with a well-defined structure and catalytic mechanism. The findings highlight the significant potential of conformational engineering.

Objective This study conducted molecular biological identification of the viruses carried by Culex pipiens pallens specimens collected in Shunyi District, Beijing in 2023, and observed the changes in the infection rate of the viruses carried by Cx. pipiens pallens at different collection times. Methods Cx. pipiens pallens were collected using carbon dioxide mosquito traps. The mosquito samples were ground in batches and analyzed by molecular biology technologies. The virus infection rate at different collection times was analyzed statistically. Results 17 strains of Culex pipiens pallens densovirus(CppDNV)were identified from Cx. pipiens pallens samples collected in Shunyi District, Beijing, in 2023. The nucleotide sequence analysis of the virus genome coding region showed that CppDNV was a single-stranded DNA virus with a total length of 3 335 nt, encoding 2 non-structural proteins(NS1, NS2)and 1 capsid protein(VP). The nucleotide(amino acid)sequence lengths of the three proteins were 2 376 nt(791 aa),1 092 nt(363 aa)and 1 071 nt(356 aa), respectively. Phylogenetic analysis showed that CppDNV was located in genus Brevihamaparvovirus. Statistical analysis showed no significant difference in infection rates across collection times(χ2=4.429, P=0.194). Conclusions CppDNV was identified in Cx. pipiens pallens in Beijing, and it was stably maintained in this natural population.

Objective To investigate the species composition of mosquitoes and breeding conditions of larvae in the rice planting areas of Beijing, and to provide a scientific basis for mosquito control in rice fields. Methods Adult mosquitoes were collected using CO2-baited light traps, and mosquito larvae(including pupae)were sampled via the dipping method. Results A total of 4 genera and 6 species of adult mosquitoes were captured in the study area. The dominant species were Culex pipiens pallens, Cx. tritaeniorhynchus, and Anopheles sinensis. The average adult mosquito density was 5.11 specimens per trap-hour, with slightly lower density in July compared to August. For larvae and pupae,3 genera and 4 species were identified, dominated by Cx. tritaeniorhynchus, An. sinensis, and Aedes vexans. Conclusions The mosquito species composition in Beijing′s rice planting areas is diverse. Mosquito control strategies should prioritize the management of adult mosquitoes, while density control of mosquito larvae in paddy fields can be achieved through intermittent irrigation techniques.

Objective To explore the effects of gasless endoscopic thyroidectomy via axillary approach on neck function and aesthetic effect in patients with early thyroid tumor.Methods A prospective study was conducted on 116 patients with early thyroid tumor admitted to our hospital from December 2020 to December 2023.They were divided into the observation group and the control group according to block random method,with 58 cases in each group.Patients in the control group underwent open thyroidectomy,while patients in the observation group underwent gasless endoscopic thyroidectomy via axillary approach.The surgical indicators,neck function,cosmetic effect,and complications of patients in the two groups were compared.Results Compared with the control group,the observation group had a longer surgical time(P<0.05),less intraoperative bleeding and postoperative drainage volume(P<0.05).There were statistically significant differences in terms of the time point,inter-group and interaction effects of the neck injury index and the time point and inter-group effects of swallowing disorder index of patients between the two groups(P<0.05).Compared with 3 days after surgery,the neck injury index and swallowing disorder index at 6 months and 12 months after surgery of patients in both groups decreased(P<0.05),and the neck injury index and swallowing disorder index at 6 months and 12 months after surgery of patients in the observation group were lower than those in the control group(P<0.05).Compared with the control group,the observation group had better cosmetic effects(P<0.05).The total incidence of complications of patients in the observation group was lower than that in the control group(P<0.05).Conclusion Gasless endoscopic thyroidectomy via axillary approach has better efficacy for early thyroid tumor,which can effectively improve neck function and aesthetic effect,promote the recovery of patients,and has high safety and patient satisfaction.

The p21-activated kinase 4 (PAK4), a key regulator of malignancy, is negatively correlated with immune infiltration and has become an emergent drug target of cancer therapy. Given the lack of high efficacy PAK4 inhibitors, we herein reported the identification of a novel inhibitor 13 bearing a tetrahydrobenzofuro[2,3-c]pyridine tricyclic core and possessing high potency against MIA PaCa-2 and Pan02 cell lines with IC₅₀ values of 0.38 and 0.50 μmol/L, respectively. This compound directly binds to PAK4 in a non-ATP competitive manner. In the mouse Pan02 model, compound 13 exhibited significant tumor growth inhibition at a dose of 100 mg/kg, accompanied by reduced levels of PAK4 and its phosphorylation together with immune infiltration in mice tumor tissue. Overall, compound 13 is a novel allosteric PAK4 inhibitor with a unique tricyclic structural feature and high potency both in vitro and in vivo, thus making it worthy of further exploration.

Advanced atherosclerosis is the major global cause of death, as featured by the aggregation of apoptotic cells (ACs) in necrotic cores. The defective efferocytosis and dysfunctional cholesterol efflux of macrophages are the main reasons for forming necrotic cores in advanced atherosclerosis. In this study, we constructed self-assembled procyanidins (PC) NPs for loading pitavastatin (Pita). The designed HA@PC@Pita NPs with hyaluronic acid (HA) modification combined the advantages of efferocytosis restoration of Pita and cholesterol efflux enhancement of PC. In vitro assay indicated that HA@PC@Pita NPs could induce M1/M2 repolarization and upregulate ERK5/Mertk expression to restore efferocytosis of macrophages. Simultaneously, HA@PC@Pita NPs notably promoted cholesterol efflux by promoting macrophage lipophagy, a selective autophagy of lipid droplets. In vivo study showed that HA@PC@Pita NPs cleared necrotic core and enhanced plaque stability in the ApoE ^-/- mice model with advanced atherosclerosis. Taken together, this study demonstrated the potential of HA@PC@Pita NPs for the treatment of advanced atherosclerosis.

Bombesin receptor subtype-3 (BRS3) is an orphan G protein-coupled receptor (GPCR) that plays critical roles in energy homeostasis, glucose metabolism, and insulin secretion. Recent structural studies have elucidated BRS3 signaling mechanisms using synthetic ligands, including BA1 and MK-5046. However, the molecular basis of BRS3 activation by bioactive natural compounds and their derivatives, particularly those derived from traditional Chinese medicine, remains unclear. Here, we present high-resolution cryogenic electron microscopy (cryo-EM) structures of the human BRS3-G_q complex in both unliganded and active states bound by two herb-derived compounds (DSO-5a and oridonin), at resolutions of 2.9, 2.8, and 2.9 Å, respectively. These structures display distinct ligand recognition patterns between DSO-5a and oridonin. Although both compounds bind to the orthosteric pocket, they differentially engage the interaction network of BRS3, as demonstrated by mutagenesis studies assessing calcium mobilization and inositol phosphate 1 (IP1) accumulation. These findings enhance our understanding of BRS3 activation and provide valuable insights into the development of small-molecule BRS3 modulators with therapeutic potential.