1.DNA Polymerase θ: a Multifunctional and Error-prone DNA End Repair Enzyme
Yao WANG ; Guo-Jiang CHEN ; Jian-Nan FENG ; Yan-Chun SHI ; Jing WANG ; Yuan-Qiang ZHENG
Progress in Biochemistry and Biophysics 2024;51(3):493-503
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.
2.Analysis of the biosynthesis pathways of phenols in the leaves of Tetrastigma hemsleyanum regulated by supplemental blue light based on transcriptome sequencing
Hui-long XU ; Nan YANG ; Yu-yan HONG ; Meng-ting PAN ; Yu-chun GUO ; Shi-ming FAN ; Wen XU
Acta Pharmaceutica Sinica 2024;59(10):2864-2870
Analyze the changes in phenolic components and gene expression profiles of
3.Schisandrin A ameliorates DSS-induced acute ulcerative colitis in mice via regulating the FXR signaling pathway
Jia-rui JIANG ; Kua DONG ; Yu-chun JIN ; Xin-ru YANG ; Yi-xuan LUO ; Shu-yang XU ; Xun-jiang WANG ; Li-hua GU ; Yan-hong SHI ; Li YANG ; Zheng-tao WANG ; Xu WANG ; Li-li DING
Acta Pharmaceutica Sinica 2024;59(5):1261-1270
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
4.Prediction of Wind Turbine Lubricating Oil's Acid Value by Ordinary Least Square Method Based on Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy Through Higher-Order Derivative Combined with Angular Metric
Chun-Hui GE ; Yan-Jun LIU ; Meng-Shi CHEN ; Ce YANG ; Pei-Pei LIANG ; Zhi-Xiang YAO ; Kai ZHANG
Chinese Journal of Analytical Chemistry 2024;52(9):1254-1265,中插1-中插4
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.
5.Risk factors of gastrointestinal bleeding after type A aortic dissection
Shi-Si LI ; Chun-Shui LIANG ; Tian-Bo LI ; Yun ZHU ; Han-Ting LIU ; Xing-Lu WANG ; Si ZHANG ; Rui-Yan MA
Journal of Regional Anatomy and Operative Surgery 2024;33(6):497-500
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.
6.Effects of climate change on scrub typhus in Xiamen
Xue-Mei KE ; Jiao-Na CHEN ; Shan-Shan MA ; Si-Han WU ; Chun-Xiang CAI ; Xiao-Yan WANG ; Shi-Jie HUANG
Chinese Journal of Zoonoses 2024;40(10):965-970
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.
7.NDRG2 Activates Endoplasmic Reticulum Stress via IRE1α-XBP1 to Reverse Tamoxifen Resistance in ER+Breast Cancer
Shou-Ying WANG ; Yan-Yan DU ; Peng CAO ; Wen-Yu LIU ; Jun-Yu QI ; Wei-Ye SHI ; Chun-Xiao ZHANG ; Xiao-Lei ZHOU
Chinese Journal of Biochemistry and Molecular Biology 2024;40(10):1409-1416
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.
8.Diagnosis and Risk Stratification of Acute Myeloid Leukemia,Myelodysplasia-Related
Hui YANG ; Rui GUO ; Yu SHI ; Chun QIAO ; Yan WANG ; Yu-Jie WU ; Hai-Rong QIU
Journal of Experimental Hematology 2024;32(5):1372-1376
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.
9.Insomnia Burden among Informal Caregivers of Hospitalized Lung Cancer Patients and Its Influencing Factors.
Chun Yan LI ; Yu Jian SONG ; Lan ZHAO ; Mu Hong DENG ; Rui Xin LI ; Xiao Ling ZHANG ; Qiong Xuan LI ; Ying SHI ; Heng Yu LUAN ; Yuan Yuan SUN ; Yi HU ; Xiao Yong SAI
Biomedical and Environmental Sciences 2023;36(8):715-724
OBJECTIVE:
This study aimed to reveal the insomnia burden and relevant influencing factors among informal caregivers (ICs) of hospitalized patients with lung cancer.
METHODS:
A cross-sectional study on ICs of hospitalized patients with lung cancer was conducted from December 31, 2020 to December 31, 2021. ICs' burden was assessed using the Caregiver Reaction Assessment (CRA), Hospital Anxiety and Depression Scale (HADS), and Insomnia Severity Index (ISI). Linear and logistic regression models were used to identify the influencing factors.
RESULTS:
Among 289 ICs of hospitalized patients with lung cancer, 83 (28.72%), 53 (18.34%), and 14 (4.84%) ICs experienced mild, moderate, and severe insomnia, respectively. The scores concerning self-esteem, lack of family support, financial problems, disturbed schedule, and health problems were 4.32 ± 0.53, 2.24 ± 0.79, 2.84 ± 1.14, 3.63 ± 0.77, and 2.44 ± 0.95, respectively. ICs with higher Activities of Daily Living Scale (ADLS) scores were associated with a lower risk of insomnia, with an odd ratio ( OR) and 95% confidence interval ( CI) of 0.940 (0.898-0.983). Among the ICs, female gender ( OR = 2.597), alcohol consumption ( OR = 3.745), underlying medical conditions ( OR = 11.765), long-term caregiving experience ( OR = 37.037), and higher monthly expenses ( OR = 5.714) were associated with a high risk of insomnia.
CONCLUSION
Of the hospitalized patients with lung cancer, 51.9% experienced insomnia. Patients' ADL, ICs gender, alcohol consumption, underlying medical conditions, caregiving duration, and monthly expenses were influencing factors. Therefore, prompt screening and early intervention for ICs of patients with lung cancer is necessary.
Humans
;
Female
;
Caregivers
;
Activities of Daily Living
;
Cross-Sectional Studies
;
Sleep Initiation and Maintenance Disorders/epidemiology*
;
Lung Neoplasms/epidemiology*
10.Cholesterol paradox in the community-living old adults: is higher better?
Sheng-Shu WANG ; Shan-Shan YANG ; Chun-Jiang PAN ; Jian-Hua WANG ; Hao-Wei LI ; Shi-Min CHEN ; Jun-Kai HAO ; Xue-Hang LI ; Rong-Rong LI ; Bo-Yan LI ; Jun-Han YANG ; Yue-Ting SHI ; Huai-Hao LI ; Ying-Hui BAO ; Wen-Chang WANG ; Sheng-Yan DU ; Yao HE ; Chun-Lin LI ; Miao LIU
Journal of Geriatric Cardiology 2023;20(12):837-844
OBJECTIVE:
To evaluate the associations of lipid indicators and mortality in Beijing Elderly Comprehensive Health Cohort Study.
METHODS:
A prospective cohort was conducted based on Beijing Elderly Comprehensive Health Cohort Study with 4499 community older adults. After the baseline survey, the last follow-up was March 31, 2021 with an average 8.13 years of follow-up. Cox proportional hazard model was used to estimate the hazard ratios (HR) with 95% CI for cardiovascular disease (CVD) death and all-cause death in associations with baseline lipid indicators.
RESULTS:
A total of 4499 participants were recruited, and the mean levels of uric acid, body mass index, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, total cholesterol (TC), triglyceride, and low-density lipoprotein cholesterol (LDL-C) showed an upward trend with the increasing remnant cholesterol (RC) quarters (Ptrend < 0.05), while the downward trend was found in high-density lipoprotein cholesterol (HDL-C). During the total 36,596 person-years follow-up, the CVD mortality and all-cause mortality during an average 8.13 years of follow-up was 3.87% (95% CI: 3.30%-4.43%) and 14.83% (95% CI: 13.79%-15.86%) with 174 CVD death participants and 667 all-cause death participants. After adjusting for confounders, the higher level of TC (HR = 0.854, 95% CI: 0.730-0.997), LDL-C (HR = 0.817, 95% CI: 0.680-0.982) and HDL-C (HR = 0.443, 95% CI: 0.271-0.724) were associated with lower risk of CVD death, and the higher level of HDL-C (HR = 0.637, 95% CI: 0.501-0.810) were associated with lower risk of all-cause death. The higher level of RC (HR = 1.276, 95% CI: 1.010-1.613) increase the risk of CVD death. Compared with the normal lipid group, TC ≥ 6.20 mmol/L group and LDL-C ≥ 4.10 mmol/L group were no longer associated with lower risk of CVD death, while RC ≥ 0.80 mmol/L group was still associated with higher risk of CVD death. In normal lipid group, the higher levels of TC, LDL-C and HDL-C were related with lower CVD death.
CONCLUSIONS
In community older adults, higher levels of TC and HDL-C were associated with lower CVD mortality in normal lipid reference range. Higher RC was associated with higher CVD mortality, which may be a better lipid indicator for estimating the CVD death risk in older adults.

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