DNA polymerase theta (Polθ), also known as DNA polymerase θ, is the member of the DNA polymerase A family and plays a crucial role in the repair of DNA double-strand breaks (DSB). Polθ has 3 distinct structural domains: the N-terminal helicase-like domain with a conserved sequence, the C-terminal polymerase domain, and the central domain, which is a disordered sequence connecting these two regions. Notably, Polθ is the only known polymerase in eukaryotes that possesses helicase activity. However, it is also an error-prone polymerase. When DNA DSBs occur, a specialized network consisting of at least 4 pathways, including classical-non homologous end joining (C-NHEJ), homologous recombination (HR), single-strand annealing (SSA), and alternative-end joining (Alt-EJ), is responsible for repairing DNA damage caused by DSBs. In the absence of major DNA repair pathways like HR, cells rely on Alt-EJ pathway mediated by Polθ to repair damaged DNA and maintain genomic stability. Nevertheless, due to the low fidelity of Polθ, Alt-EJ repair often leads to errors. Depletion of Polθ has shown to increases DSB formation and compromise genomic stability. Conversely, overexpression of Polθ has been associated with increases DNA damage markers and impairs cell cycle progression. As a result, the impact of Polθ on genome stability remains controversial. Furthermore, overexpression of Polθ is frequently observed in cancer and is associated with a characteristic mutational signature and poor prognosis. Depleting Polθ in an HR-deficient background has been shown to impair cell viability, suggesting a synthetic lethal (SL) relationship between Polθ and HR factors. In recent years, targeted chemotherapy drugs that inhibit tumor growth have gained significant attention. However, off-target effects and drug resistance pose challenges for clinical application, particularly with poly-ADP-ribose polymerase inhibitor (PARPi). Blocking Polθ activity in HR-deficient tumor cells has been found to reverse PARPi resistance, making Polθ a very promising therapeutic target in cancer treatment. The availability of crystal structures for both helicase and polymerase domain has facilitated the design of potent inhibitors of Polθ. Currently, several highly specific and effective small molecule inhibitors targeting Polθ, such as Novobiocin, RP-6685, and ART558, have been reported to effectively block various cancers with HR deficiency. The initial success of these inhibitors points to new directions for treating BRCA1/2-mutated tumors. Additionally, reducing the Alt-EJ repair pathway mediated by Polθ can improve HR repair efficiency and increase the chance of exogenous gene target integration (TI), suggesting potential new applications for Polθ inhibitors. This article reviews the recent research progress on the molecular function of Polθ and its involvement in the Alt-EJ pathway modification mechanism, providing insights for a deeper understanding of this field.

Analyze the changes in phenolic components and gene expression profiles of Tetrastigma hemsleyanum leaves with supplemental blue light, and screen differentially expressed genes related to phenolic metabolism, providing a basis for improving the quality of T. hemsleyanum leaves. Using the leaves of T. hemsleyanum under supplemental blue light and visible light as research materials, the content of phenolic components such as neochlorogenic acid, chlorogenic acid, and 3-O-coumaroyl quinic acid was significantly increased by supplemental blue light. A total of 102 949 unigenes were obtained from the transcriptome, including 14 564 differentially expressed unigenes. They can be divided into 52 subclasses by gene ontology (GO) function, kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis showed that these differentially expressed unigenes were significantly enriched in phenolic metabolic pathways such as phenylpropane biosynthesis, flavonoid biosynthesis and isoflavone biosynthesis. A total of 63 differentially expressed unigenes were identified in the pathways related to the biosynthesis of phenolic cpmponents, including 19 key enzymes such as phenylalanine ammonia-lyase (PAL), cinnamyl-alcohol dehydrogenase (CAD), flavonol synthase (FLS), and so on. This study greatly enriched the genetic data information of T. hemsleyanum and laid a foundation for analyzing the mechanism of blue light promoting the biosynthesis of phenols and molecular breeding of T. hemsleyanum.

Inflammatory bowel disease (IBD) is characterized by chronic relapsing intestinal inflammation and encompasses ulcerative colitis (UC) and Crohn's disease (CD). IBD has emerged as a global healthcare problem. Clinically efficacious therapeutic agents are deficient. This study concentrates on models of ulcerative colitis with the objective of discovering novel therapeutic strategies. Previous investigations have established that schisandrin A demonstrates anti-inflammatory effects in vitro, concurrently enhancing the transcriptional activity of farnesoid X receptor (FXR). FXR inversely modulates the transcriptional activity of NF-κB, which has an important role in regulating inflammatory responses. Consequently, the current study was to explore the safeguarding influence of schisandrin A on ulcerative colitis and delineate the mechanism by which it regulates this effect through the FXR signaling pathway. The effect of schisandrin A on the mRNA levels of inflammatory factors was evaluated in RAW264.7 cells. The dual luciferase reporter gene assay was used to verify the relationship between schisandrin A and FXR targeting. The animal experiments were performed in accordance with the regulations of the Animal Ethics Committee of Shanghai University of Traditional Chinese Medicine (approval No. PZSHUTCM2304250005). Acute ulcerative colitis was induced in wild-type or FXR knockout C57BL/6 mice by drinking 3% dextran sodium sulfate (DSS) for 7 days, and schisandrin A was administered via gavage for a continuous treatment period of 7 days. The body weight and faecal were monitored daily. The mRNA levels of inflammatory factors in colon tissue and FXR target genes were measured by RT-qPCR. The findings revealed that schisandrin A, in vitro, impeded the lipopolysaccharide (LPS)-induced elevation in mRNA levels of inflammatory factors and schisandrin A could augment transcriptional activity of FXR. In wild-type mice, schisandrin A significantly improved weight loss, colon shortening, loose stools and blood in stools in mice with acute ulcerative colitis, and schisandrin A significantly reduced the expression of pro-inflammatory factors genes and significantly increased the expression of FXR target genes in colon tissues. In FXR knockout mice, the administration of schisandrin A failed to yield ameliorative effect on acute ulcerative colitis in mice. In conclusion, schisandrin A can reduce intestinal inflammation through the FXR signaling pathway to alleviate acute ulcerative colitis in mice. Implications arise that Schisandra lignans could serve as lead compounds for drug development aimed at inflammatory bowel disease.

To address the key challenges in multivariate statistical modeling,a higher-order derivative approach combined with vector space angle multiplicative error correction was proposed for establishing an acid value prediction ordinary least squares(OLS)regression model based on attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy.By using acid values measured by potentiometric titration as reference,ATR-FTIR spectroscopy was utilized for direct calibration and prediction of acid values on 96 kinds of lubricating oil samples from a wind turbine.Firstly,the simulated hyperbolic(SH)method was employed to obtain accurate fourth derivative spectrum,resolving overlapping bands and enhancing spectral selectivity.Then,from the calibration set(48 samples),informative spectral regions were identified based on correlation coefficients.Next,the sample with the highest acid value was selected as the reference and1/(1+tan(θ/2))was used as the metric relation of the spectrum to suppress the multiplicity error caused by factors such as the change of effective optical path in ATR-FTIR spectroscopy.After pretreatment of the spectrum by the method of fourth-order derivative combined with angular quantity,the number of variables decreased from 1737 to 8,and the matrix condition number decreased from 1.85×1015 to 56.34,which effectively eliminated the collinearity issue for OLS regression.Direct OLS modeling on spectral preprocessed data achieved a determination coefficient of 0.981 for 47 validation samples,with a relative error range of-8.38%-8.22%,outperforming the commonly used partial least squares(PLS)method(Determination coefficient of 0.865,relative error of-27.82%-22.38%).It was proved that effective data preprocessing significantly improved the prediction accuracy of the model.Furthermore,when the number of calibration set was compressed to 25 and the number of validation set was expanded to 70,the model retained 8 variables with a condition number of 42.60,the determination coefficient of validation set was 0.972,and the relative error ranged from-10.80%to 12.31%.Comparing with the PLS method(Determination coefficient of 0.724,relative error of-34.26%-53.84%),the improvement was more obvious,which showed that the method could still have high prediction accuracy even with fewer modeling samples as well as robustness against multiplicative error interference.

Objective To analyze the risk factors of gastrointestinal bleeding in patients with type A aortic dissection(TAAD)after Sun's operation.Methods The clinical data of 87 patients who underwent TAAD Sun's operation in our hospital from March 2021 to June 2022 were retrospectively analyzed.They were divided into the bleeding group and the non-bleeding group according to whether there was gastrointestinal bleeding after operation.The clinical data of patients in the two groups was compared and analyzed.The binary Logistic regression analysis was used to analyze the risk factors of gastrointestinal bleeding.The clinical predictor of postoperative gastrointestinal bleeding was analyzed by receiver operating characteristic(ROC)curve.Results In this study,there were 40 cases of postoperative gastrointestinal bleeding(the bleeding group)and 47 cases of non-bleeding(the non-bleeding group).Compared with the non-bleeding group,the bleeding group had a shorter onset time,a higher proportion of patients with hypertension history,a higher preoperative creatinine abnormality rate,more intraoperative blood loss,longer postoperative mechanical ventilation time,higher postoperative infection rate,and higher poor prognosis rate,with statistically significant differences(P<0.05).There was no statistically significant difference in the gender,age,gastrointestinal diseases history,smoking history,preoperative platelets,preoperative international normalized ratio(INR),preoperative alanine aminotransferase(ALT),preoperative aspartate aminotransferase(AST),preoperative γ-glutamyl transpeptidase(GGT),preoperative dissection involving abdominal aorta,operation time,intraoperative cardiopulmonary bypass time,intraoperative circulatory arrest time,intraoperative aortic occlusion time or intraoperative blood transfusion rate.Logistic regression analysis showed that hypertension history(OR=2.468,95%CI:0.862 to 7.067,P=0.037),preoperative creatinine>105 μmol/L(OR=3.970,95%CI:1.352 to 11.659,P=0.011),long postoperative mechanical ventilation time(OR=1.015,95%CI:0.094 to 1.018,P=0.041)and postoperative infection(OR=3.435,95%CI:0.991 to 11.900,P=0.012)were the independent risk factors for postoperative gastrointestinal bleeding in TAAD patients.ROC curve showed that the postoperative mechanical ventilation time exceeding 64 hours were the clinical predictor of postoperative gastrointestinal bleeding in TAAD patients.Conclusion The prognosis of TAAD patients with postoperative gastrointestinal bleeding after Sun's operation is poor.Hypertension history,preoperative acute renal insufficiency,long postoperative mechanical ventilation time and postoperative infection are closely related to postoperative gastrointestinal bleeding in TAAD patients after operation,which should be paid more attention to,and corresponding evaluation,early identification and early intervention should be made to improve the prognosis of patients.

This study was aimed at examining the influence of meteorological factors on scrub typhus in Xiamen.Scrub ty-phus monitoring data and meteorological factors were collected in Xiamen from 2005 to 2023.Spearman correlation analysis and nonlinear regression were used to analyze the correlation between scrub typhus incidence and meteorological factors.The inci-dence of scrub typhus first increased and subsequently decreased in Xiamen from 2005 to 2023.The highest incidence was be-tween 2014 and 2016,and the peak incidence was from June to October.The monthly incidence of scrub typhus positively cor-related with daily minimum temperature(r=0.637,P＜0.001,daily average temperature(r=0.627,P＜0.001),daily maxi-mum temperature(r=0.612,P＜0.001),sunshine duration(r=0.405,P＜0.001),average relative humidity(r=0.346,P＜0.001),and daily rainfall(r=0.207,P=0.002),and negatively correlated with average atmospheric pressure(r=-0.549,P＜0.001),whereas no correlation was observed with the average wind speed in Xiamen.The regression equation of scrub ty-phus monthly incidence and meteorological parameters was y=-433.869-11.503x1+0.381x1 2+9.150x2-0.197x2 2+3.936 x3-0.132x3 2+0.881x4+0.035x4 2-1.048x5+0.009x5 2+0.186x6-0.023x6 2+0.421x7+6.210×10-5x8-1.051 × 10-10x8 2 in Xiamen,and the R2 was 0.473,thus indicating good model fit.Scrub typhus incidence correlated with the daily minimum av-erage temperature,average temperature,daily maximum tem-perature,sunshine duration,daily rainfall,relative humidity,and average atmospheric pressure in Xiamen.Various meteoro-logical factors had differing effects on scrub typhus.

Tamoxifen(TAM)has been widely used for the treatment of ER+breast cancer.However,the inevitable emergence of resistance to tamoxifen obstructs the successful treatment of this cancer.The tumor suppressor gene N-myc downstream-regulated gene 2(NDRG2)plays a significant role in the de-velopment of ER+breast cancer.However,it is unclear whether NDRG2 participates in mediating TAM resistance in ER+breast cancer.Here,we investigate the expression of NDRG2 mRNA and protein in TAM-sensitive and TAM-resistant ER+breast cancer cells.The results of immunoblotting experiments re-vealed a negative correlation between NDRG2 expression and TAM resistance ability in ER+breast cancer cells(P＜0.001).CCK-8 cell viability assays and soft agar colony formation assays showed that NDRG2 overexpression in TAM resistant cells significantly reduced the TAM IC50 value and the soft agar colony formation rate(P＜0.001).For the mechanism,the ERAD reporter protein assays showed that NDRG2 overexpression upregulated the expression of the ERAD reporter protein CD3ε-YFP and increased the lev-els of spliced XBP1s mRNA,leading to severe endoplasmic reticulum stress in TAM resistant cells(P＜0.001).Immunoblot analysis confirmed that overexpression of NDRG2 significantly increased the level of phosphorylation of the endoplasmic reticulum stress sensor IRE 1α and the expression levels of its down-stream protein factors,including ERdj4,P58IPK,EDEM and PDIA5(P＜0.001).The in vivo xenograft tumor experiments in mice further verified that NDRG2 overexpression significantly inhibited the growth of resistant tumors,which enhanced the therapeutic effect of TAM(P＜0.001).These findings indicate that increasing NDRG2 expression and triggering severe endoplasmic reticulum stress upon TAM treatment can reverse the resistance of ER+breast cancer cells to TAM and inhibits the growth of ER+breast canc-er tumors.Our results provide valuable new insights and potential targets for improving the clinical man-agement of TAM-resistance and prognosis in ER+breast cancer.

Objective:To analyze the clinical and genetic characteristics of acute myeloid leukemia,myelodysplasia-related(AML-MR)patients and evaluate their prognostic risk stratification,to guide clinical treatment decisions and improve understanding of the biological characteristics and disease progression.Methods:The study analyzed cellular and molecular genetic information of 307 AML-MR patients,diagnosed based on clinical history,bone marrow morphology,cytogenetics,and molecular genetic abnormalities.The risk stratification followed the 2022 ELN guidelines.Results:57 cases(18.6％)met the AML-MR diagnostic criteria based on morphology and clinical history,110 cases(37.2％)met the AML-MR diagnostic criteria based on cytogenetic results,and 210 cases(74.5％)met the AML-MR diagnostic criteria based on molecular testing results.Among different type of mutations,ASXL1 mutation was the most frequent,followed by SRSF2 and BCOR mutations.Except for 2 cases with incomplete data that could not be classified.263(86.2％)of the 305 patients were classified as poor prognosis,20(6.6％)were classified as good prognosis group,and 22(7.2％)were classified as intermediate prognosis group.Conclusion:Molecular genetic information plays a crucial role in diagnosing AML-MR,highlighting the importance of genetics in diagnosis and prognosis.Most AML-MR patients fall into poor prognosis categories,necessitating early intensive and targeted therapy for better survival outcomes.

Objective:The study aimed to analyze the clinical and endoscopic characteristics of adult celiac disease (CD) to provide a scientific basis for more effective CD diagnosis and treatment.Methods:In this cross-sectional study, the clinical and endoscopic data of 96 adult CD patients treated in the Department of Gastroenterology of the People′s Hospital of Xinjiang Uygur Autonomous Region from March 2016 to December 2021 were retrospectively collected and analyzed.Results:A total of 96 CD patients were diagnosed, including 33 men and 63 women. The average age was 47±14 years (range, 18-81 years). The disease occurred mainly in the age group of 31-60 years. The median course of the disease was 2.0 (0.2-40.0) years. There were 41 (42.7%) classical and 55 (57.3%) non-classical CD patients. All patients with classical CD showed chronic diarrhea, often accompanied by abdominal pain (46.3%, 19/41), abdominal distension (17.1%, 7/41), anemia (65.9%, 27/41), and chronic fatigue (48.8%, 20/41). The main manifestations of non-classical CD were chronic abdominal pain (58.2%, 32/55), abdominal distension (32.7%, 18/55), anemia (40.0%, 22/55), and osteopenia/osteoporosis (38.2%, 21/55). Compared with non-classical CD, anemia developed more frequently in classical CD, and the difference was statistically significant ( P = 0.012). The incidence of complications in CD patients was 36.5% (35/96), and the main complications were thyroid disease (19.8%, 19/96), connective tissue disease (6.2%, 6/96), and kidney disease (6.2%, 6/96). There was no significant difference between classical and non-classical CD ( P>0.05). The frequency of endoscopic manifestations in CD patients was 84.4% (81/96). Duodenal bulb endoscopy showed nodular changes (72.9%, 70/96), grooved changes (10.4%, 10/96), and focal villous atrophy (9.4%, 9/96). The main manifestations of descending endoscopy were the decrease, flattening, or disappearance of duodenal folds (43.8%, 42/96), scallop-like changes (38.5%, 37/96), and nodular changes (34.4%, 33/96). Conclusions:Adult CD patients are mostly female. CD occurred mainly in the age group of 31-60 years. The clinical manifestations were mainly those of non-classical CD. Some patients often had other autoimmune diseases. Patients with characteristic endoscopic manifestations should be warned about the possibility of developing CD. Clinicians should strengthen the understanding of CD and reduce the related rates of missed diagnosis.

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased (OR=0.921, 95%CI: 0.889-0.954). Compared with the lowest quartile(Q₁) of blood selenium, the ORs (95%CI) of Q₃ and Q₄ blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment (P_nonlinear>0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.
Aged, 80 and over ; Female ; Humans ; Selenium ; Cohort Studies ; Cross-Sectional Studies ; Metals/analysis* ; Cognitive Dysfunction/epidemiology* ; China/epidemiology*