Gastric cancer remains one of the most prevalent and lethal malignancies of the digestive tract worldwide,underscoring the urgent need for more effective targeted therapeutic strategies.Poly(ADP-ri-bose)polymerase(PARP)inhibitors have demonstrated remarkable efficacy in tumors with homologous recombination repair(HRR)deficiency;however,their clinical application in gastric cancer remains limited.Clinical evidence suggests that patients harboring Helicobacter pylori infection in combination with HRR gene mutations exhibit a significantly elevated risk of developing gastric cancer,thereby supporting the potential benefit of PARP inhibition in this setting.In this study,a kinase inhibitor library was screened in combination with the PARP inhibitor olaparib in gastric cancer cells.And we identify the cy-clin-dependent kinase 8/19(CDK8/19)inhibitor Senexin A as a compound that synergistically enhances the cytotoxic effect of PARP inhibition(P<0.05).Phenotypic validation using CCK-8 and colony for-mation assays demonstrated that the combination treatment significantly suppressed cellular proliferation and clonogenic potential compared to either monotherapy(P<0.0001).Mechanistically,alkaline comet assays revealed a significant increase in DNA damage in the combination treatment group relative to either single-agent group(P<0.0001),suggesting that the synergistic effect results from the exacerbation of DNA damage via impaired DNA repair mechanisms.In addition,treatment with CDK8/19 inhibitors a-lone markedly increased the formation of γH2AX and 53BP1 foci in irradiated gastric cancer cells(P<0.0001),indicating inhibition of DNA damage repair pathways.Transcriptome sequencing further re-vealed that CDK8/19 inhibition impacts critical cellular pathways,including DNA repair,cell cycle reg-ulation,and RNA splicing.Co-immunoprecipitation assays confirmed that inhibition of CDK8/19 kinase activity significantly reduces the phosphorylation level of PARP1,suggesting a potential regulatory inter-action.Immunohistochemical analysis of tumor and adjacent non-tumor tissues from gastric cancer pa-tients demonstrated that CDK8 is significantly overexpressed in tumor tissues,supporting its potential as both a prognostic biomarker and a therapeutic target.Collectively,this study elucidates a mechanistic ba-sis by which CDK8/19 inhibition enhances the sensitivity of gastric cancer cells to PARP inhibitors.These findings provide a strong rationale for the combined use of CDK8/19 and PARP inhibitors as a tar-geted therapeutic strategy and offer promising translational implications for advancing personalized medi-cine in gastric cancer treatment.

Glycoengineering was carried out in the mammalian cell line CHO for the production of pro-tein-based drugs.Firstly,the genome sequence of the Rosa26 locus of CHO cells was determined,the gRNA sequences were designed,and the landing pad was integrated into the Rosa26 locus of CHO cells by CRISPR/Cas9 technology.Three targeting vectors co-expressed by glycosyltransferases,which are β-1,4 galactosyltransferase(B4GALT1),α-2,6-sialyltransferase 1(ST6GAL1)and N-acetaminoglycosyl-transferase Ⅲ(GnT Ⅲ),were constructed by overlapping PCR and seamless ligation technology,and the three glycosyltransferase genes were integrated into the CHO Rosa26 locus by Cre enzyme-mediated cassette exchange technology.PCR confirmed that three glycosyltransferases had been successfully site-directed integrated into the Rosa26 site.The mRNA expression levels of the three glycosyltransferases were more than 50 000-fold by qRT-PCR,and the protein expression levels of the three glycosyltrans-ferases were more than 4-fold via western blotting(P＜0.001).A CHO-engineered cell line with three glycosyltransferases integrated into Rosa26 site was successfully constructed.

Gastric cancer remains one of the most prevalent and lethal malignancies of the digestive tract worldwide,underscoring the urgent need for more effective targeted therapeutic strategies.Poly(ADP-ri-bose)polymerase(PARP)inhibitors have demonstrated remarkable efficacy in tumors with homologous recombination repair(HRR)deficiency;however,their clinical application in gastric cancer remains limited.Clinical evidence suggests that patients harboring Helicobacter pylori infection in combination with HRR gene mutations exhibit a significantly elevated risk of developing gastric cancer,thereby supporting the potential benefit of PARP inhibition in this setting.In this study,a kinase inhibitor library was screened in combination with the PARP inhibitor olaparib in gastric cancer cells.And we identify the cy-clin-dependent kinase 8/19(CDK8/19)inhibitor Senexin A as a compound that synergistically enhances the cytotoxic effect of PARP inhibition(P<0.05).Phenotypic validation using CCK-8 and colony for-mation assays demonstrated that the combination treatment significantly suppressed cellular proliferation and clonogenic potential compared to either monotherapy(P<0.0001).Mechanistically,alkaline comet assays revealed a significant increase in DNA damage in the combination treatment group relative to either single-agent group(P<0.0001),suggesting that the synergistic effect results from the exacerbation of DNA damage via impaired DNA repair mechanisms.In addition,treatment with CDK8/19 inhibitors a-lone markedly increased the formation of γH2AX and 53BP1 foci in irradiated gastric cancer cells(P<0.0001),indicating inhibition of DNA damage repair pathways.Transcriptome sequencing further re-vealed that CDK8/19 inhibition impacts critical cellular pathways,including DNA repair,cell cycle reg-ulation,and RNA splicing.Co-immunoprecipitation assays confirmed that inhibition of CDK8/19 kinase activity significantly reduces the phosphorylation level of PARP1,suggesting a potential regulatory inter-action.Immunohistochemical analysis of tumor and adjacent non-tumor tissues from gastric cancer pa-tients demonstrated that CDK8 is significantly overexpressed in tumor tissues,supporting its potential as both a prognostic biomarker and a therapeutic target.Collectively,this study elucidates a mechanistic ba-sis by which CDK8/19 inhibition enhances the sensitivity of gastric cancer cells to PARP inhibitors.These findings provide a strong rationale for the combined use of CDK8/19 and PARP inhibitors as a tar-geted therapeutic strategy and offer promising translational implications for advancing personalized medi-cine in gastric cancer treatment.

This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Glycoengineering was carried out in the mammalian cell line CHO for the production of pro-tein-based drugs.Firstly,the genome sequence of the Rosa26 locus of CHO cells was determined,the gRNA sequences were designed,and the landing pad was integrated into the Rosa26 locus of CHO cells by CRISPR/Cas9 technology.Three targeting vectors co-expressed by glycosyltransferases,which are β-1,4 galactosyltransferase(B4GALT1),α-2,6-sialyltransferase 1(ST6GAL1)and N-acetaminoglycosyl-transferase Ⅲ(GnT Ⅲ),were constructed by overlapping PCR and seamless ligation technology,and the three glycosyltransferase genes were integrated into the CHO Rosa26 locus by Cre enzyme-mediated cassette exchange technology.PCR confirmed that three glycosyltransferases had been successfully site-directed integrated into the Rosa26 site.The mRNA expression levels of the three glycosyltransferases were more than 50 000-fold by qRT-PCR,and the protein expression levels of the three glycosyltrans-ferases were more than 4-fold via western blotting(P＜0.001).A CHO-engineered cell line with three glycosyltransferases integrated into Rosa26 site was successfully constructed.

BACKGROUND: Atrial fibrillation (AF) is a common cardiac arrhythmia in the elderly. This study aimed to evaluate urban-rural disparities in its prevalence and management in elderly Chinese. METHODS: Consecutive participants aged ≥ 65 years attending outpatient clinics were enrolled for AF screening using handheld single-lead electrocardiogram (ECG) from April 2017 to December 2022. Each ECG rhythm strip was reviewed from the research team. AF or uninterpretable single-lead ECGs were referred for 12-lead ECG. Primary study outcome comparison was between rural and urban areas for the prevalence of AF. The Student's t-test was used to compare mean values of clinical characteristics between rural and urban participants, while the Pearson's chi-square test was used to compare between-group proportions. Multivariate stepwise logistic regression analysis was performed to estimate the association between AF and various patient characteristics. RESULTS: The 29,166 study participants included 13,253 men (45.4%) and had a mean age of 72.2 years. The 7073 rural participants differed significantly (P ≤ 0.02) from the 22,093 urban participants in several major characteristics, such as older age, greater body mass index, and so on. The overall prevalence of AF was 4.6% (n = 1347). AF was more prevalent in 7073 rural participants than 22,093 urban participants (5.6% vs. 4.3%, P < 0.01), before and after adjustment for age, body mass index, blood pressure, pulse rate, cigarette smoking, alcohol consumption and prior medical history. Multivariate logistic regression analysis identified overweight/obesity (OR = 1.35, 95% CI: 1.17-1.54) in urban areas and cigarette smoking (OR = 1.62, 95% CI: 1.20-2.17) and alcohol consumption (OR = 1.42, 95% CI: 1.04-1.93) in rural areas as specific risk factors for prevalent AF. In patients with known AF in urban areas (n = 781) and rural areas (n = 338), 60.6% and 45.9%, respectively, received AF treatment (P < 0.01), and only 22.4% and 17.2%, respectively, received anticoagulation therapy (P = 0.05). CONCLUSIONS In China, there are urban-rural disparities in AF in the elderly, with a higher prevalence and worse management in rural areas than urban areas. Our study findings provide insight for health policymakers to consider urban-rural disparity in the prevention and treatment of AF.

BACKGROUND: Both medication and non-medication therapies are effective approaches to control blood pressure (BP) in hypertension patients. However, the association of joint changes in antihypertensive medication use and healthy lifestyle index (HLI) with BP control among hypertension patients is seldom reported, which needs to provide more evidence by prospective intervention studies. We examined the association of antihypertensive medication use and HLI with BP control among employees with hypertension in China based on a workplace-based multicomponent intervention program. METHODS: Between January 2013 and December 2014, a cluster randomized clinical trial of a workplace-based multicomponent intervention program was conducted in 60 workplaces across 20 urban areas in China. Workplaces were randomly divided into intervention (n = 40) and control (n = 20) groups. Basic information on employees at each workplace was collected by trained professionals, including sociodemographic characteristics, medical history, family history, lifestyle behaviors, medication status and physical measurements. After baseline, the intervention group received a 2-year intervention to achieve BP control, which included: (1) a workplace wellness program for all employees; (2) a guidelines-oriented hypertension management protocol. HLI including nonsmoking, nondrinking, adequate physical activity, weight within reference range and balanced diet, were coded on a 5-point scale (range: 0-5, with higher score indicating a healthier lifestyle). Antihypertensive medication use was defined as taking drug within the last 2 weeks. Changes in HLI, antihypertensive medication use and BP control from baseline to 24 months were measured after the intervention. RESULTS: Overall, 4655 employees were included (age: 46.3 ± 7.6 years, men: 3547 (82.3%)). After 24 months of the intervention, there was a significant improvement in lifestyle [smoking (OR = 0.65, 95% CI: 0.43-0.99; P = 0.045), drinking (OR = 0.52, 95% CI: 0.40-0.68; P < 0.001), regular exercise (OR = 3.10, 95% CI: 2.53-3.78; P < 0.001), excessive intake of fatty food (OR = 0.17, 95% CI: 0.06-0.52; P = 0.002), restrictive use of salt (OR = 0.26, 95% CI: 0.12-0.56; P = 0.001)]. Compare to employees with a deteriorating lifestyle after the intervention, those with an improved lifestyle had a higher BP control. In the intervention group, compared with employees not using antihypertensive medication, those who consistent used (OR = 2.34; 95% CI: 1.16-4.72; P = 0.017) or changed from not using to using antihypertensive medication (OR = 2.24; 95% CI: 1.08-4.62; P = 0.030) had higher BP control. Compared with those having lower HLI, participants with a same (OR = 1.38; 95% CI: 0.99-1.93; P = 0.056) or high (OR = 1.79; 95% CI: 1.27~2.53; P < 0.001) HLI had higher BP control. Those who used antihypertensive medication and had a high HLI had the highest BP control (OR = 1.88; 95% CI: 1.32-2.67, P < 0.001). Subgroup analysis also showed the consistent effect as the above. CONCLUSION These findings suggest that adherence to antihypertensive medication treatment and healthy lifestyle were associated with a significant improvement in BP control among employees with hypertension.

Apurinic/apyrimidinic endonuclease 1(APE 1)is a multifunctional protein that plays important roles in DNA repair and regulation of gene expression.Because APE 1 is overexpressed in various cancers,it can serve as a cancer biomarker for aiding clinical diagnosis,guiding therapy,and monitoring prognosis.On this basis,a label-free fluorescent probe was designed based on the primer exchange reaction(PER)strategy for highly sensitive detection of APE 1 activity.In the absence of APE 1,the structure of catalytic hairpin(HP)was stable and could not form G-quadruplex.Therefore,the background fluorescence of this sensing system was very low due to the dissociation of thioflavin T(ThT).In the presence of APE 1,the apurinic/apyrimidinic(AP)site of HP was cleaved by APE 1 and a short nucleic acid fragment that acted as a primer to initiate PER was generated.After PER reaction,a large number of G-quadruplex were produced,which could specifically bind with ThT and resulted in significant increase of fluorescence signal.The combination of low background design of HP and PER amplification made this biosensor had high sensitivity with a detection limit(3σ)of 0.0008 U/mL.Furthermore,the primer sequence was directly generated by the cleavage of APE 1 without additional addition,which not only increased the specificity of the reaction,but also simplified the experiment procedure.Moreover,the use of label-free fluorescence signal reduced the cost of the experiment,and realized rapid detection of APE 1.Finally,this sensor was used to detect APE 1 in human serum samples with spiked recoveries of 91%-104%,proving great potential in study of biological enzyme.

PURPOSE: To investigate the incidence and influencing factors of bone loss in patients with spinal cord injury (SCI). METHODS: A retrospective case-control study was conducted. Patients with SCI in our hospital from January 2019 to March 2023 were collected. According to the correlation between bone mineral density (BMD) at different sites, the patients were divided into the lumbar spine group and the hip joint group. According to the BMD value, the patients were divided into the normal bone mass group (t > -1.0 standard deviation) and the osteopenia group (t ≤ -1.0 standard deviation). The influencing factors accumulated as follows: gender, age, height, weight, cause of injury, injury segment, injury degree, time after injury, start time of rehabilitation, motor score, sensory score, spasticity, serum value of alkaline phosphatase, calcium, and phosphorus. The trend chart was drawn and the influencing factors were analyzed. SPSS 26.0 was used for statistical analysis. Correlation analysis was used to test the correlation between the BMD values of the lumbar spine and bilateral hips. Binary logistic regression analysis was used to explore the influencing factors of osteoporosis after SCI. p < 0.05 was considered statistically significant. RESULTS: The incidence of bone loss in patients with SCI was 66.3%. There was a low concordance between bone loss in the lumbar spine and the hip, and the hip was particularly susceptible to bone loss after SCI, with an upward trend in incidence (36% - 82%). In this study, patients with SCI were divided into the lumbar spine group (n = 100) and the hip group (n = 185) according to the BMD values of different sites. Then, the lumbar spine group was divided into the normal bone mass group (n = 53) and the osteopenia group (n = 47); the hip joint group was divided into the normal bone mass group (n = 83) and the osteopenia group (n = 102). Of these, lumbar bone loss after SCI is correlated with gender and weight (p = 0.032 and < 0.001, respectively), and hip bone loss is correlated with gender, height, weight, and time since injury (p < 0.001, p = 0.015, 0.009, and 0.012, respectively). CONCLUSIONS The incidence of bone loss after SCI was high, especially in the hip. The incidence and influencing factors of bone loss in the lumbar spine and hip were different. Patients with SCI who are male, low height, lightweight, and long time after injury were more likely to have bone loss.
Humans ; Spinal Cord Injuries/complications* ; Male ; Female ; Retrospective Studies ; Incidence ; Adult ; Bone Density ; Middle Aged ; Case-Control Studies ; Osteoporosis/etiology* ; Lumbar Vertebrae ; Bone Diseases, Metabolic/etiology* ; Aged ; Risk Factors