BACKGROUND:Osteoporotic fracture is the most serious complication of osteoporosis.Previous studies have demonstrated that gut microbiota has a regulatory effect on skeletal tissue and that gut microbiota has an important relationship with osteoporotic fracture,but the causal relationship between the two is unclear. OBJECTIVE:To explore the causal relationship between gut microbiota and osteoporotic fractures using Mendelian randomization method. METHODS:The genome-wide association study(GWAS)datasets of gut microbiota and osteoporotic fracture were obtained from the IEU Open GWAS database and the Finnish database R9,respectively.Using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,Mendelian randomization analyses with random-effects inverse variance weighted,MR-Egger regression,weighted median,simple model,and weighted model methods were performed to assess whether there is a causal relationship between gut microbiota and osteoporotic fracture.Sensitivity analyses were performed to test the reliability and robustness of the results.Reverse Mendelian randomization analyses were performed to further validate the causal relationship identified in the forward Mendelian randomization analyses. RESULTS AND CONCLUSION:The results of this Mendelian randomization analysis indicated a causal relationship between gut microbiota and osteoporotic fracture.Elevated abundance of Actinomycetales[odds ratio(OR)=1.562,95%confidence interval(CI):1.027-2.375,P=0.037),Actinomycetaceae(OR=1.561,95%CI:1.027-2.374,P=0.037),Actinomyces(OR=1.544,95%CI:1.130-2.110,P=0.006),Butyricicoccus(OR=1.781,95%CI:1.194-2.657,P=0.005),Coprococcus 2(OR=1.550,95%CI:1.068-2.251,P=0.021),Family ⅩⅢ UCG-001(OR=1.473,95%CI:1.001-2.168,P=0.049),Methanobrevibacter(OR=1.274,95%CI:1.001-1.621,P=0.049),and Roseburia(OR=1.429,95%CI:1.015-2.013,P=0.041)would increase the risk of osteoporotic fractures in patients.Elevated abundance of Bacteroidia(OR=0.660,95%CI:0.455-0.959,P=0.029),Bacteroidales(OR=0.660,95%CI:0.455-0.959,P=0.029),Christensenellacea(OR=0.725,95%CI:0.529-0.995,P=0.047),Ruminococcaceae(OR=0.643,95%CI:0.443-0.933,P=0.020),Enterorhabdus(OR=0.558,95%CI:0.395-0.788,P=0.001),Eubacterium rectale group(OR=0.631,95%CI:0.435-0.916,P=0.016),Lachnospiraceae UCG008(OR=0.738,95%CI:0.546-0.998,P=0.048),and Ruminiclostridium 9(OR=0.492,95%CI:0.324-0.746,P=0.001)would reduce the risk of osteoporotic fractures in patients.We identified 16 gut microbiota associated with osteoporotic fracture by the Mendelian randomization method.That is,using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,eight gut microbiota showed positive causal associations with osteoporotic fracture and another eight gut microbiota showed negative causal associations with osteoporotic fracture.The results of this study not only identify new biomarkers for the early prediction of osteoporotic fracture and potential therapeutic targets in clinical practice,but also provide an experimental basis and theoretical basis for the study of improving the occurrence and prognosis of osteoporotic fracture through gut microbiota in bone tissue engineering.

Five flavonoid glycosides were isolated from the methanol and ethyl acetate fractions of the ethanol extract of Diphylleia sinensi by using various chromatographic methods, including silica gel, MCI gel, Sephadex LH-20, ODS and semi-preparative HPLC. The structures of the isolated compounds were identified as diphyflavonoid A (1), diphyflavonoid B (2), quercetin-3-O-β-D-glucopyranoside (3), kaempferol-3-O-β-D-glucopyranoside (4), kaempferol-3-O-(6″-O-acetyl)-β-D-glucopyranoside (5) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, and MS). Compounds 1 and 2 were two new flavonoid glycosides, and compounds 3 and 5 were isolated from the genus Diphylleia for the first time.

BACKGROUND:High-methionine diet can cause liver injury in Cbs+/-mice,and hyperhomocystinemia is related to the occurrence and progression of various liver-related diseases,such as hepatic steatosis,autoimmune hepatitis,and alcoholic fatty liver disease.MicroRNAs(miRNAs)are involved in various cellular processes including cell survival,differentiation and autophagy,which are of great significance. OBJECTIVE:To investigate the critical role of miR-144-3p on Cbs+/-mouse hepatocyte autophagy induced by high methionine die. METHODS:(1)Ten male cystathione-β-synthase normal(Cbs+/+)mice and another 10 male mice with single gene knockout(Cbs+/-)of similar body mass,4 weeks of age,were fed a high-methionine diet and executed after 12 weeks to take liver tissue.(2)Human hepatocytes(HL-7702)were cultured in vitro and divided into control[0 μmol/L homocysteine(Hcy)],Hcy(100 μmol/L Hcy),mimic-NC(transfected with mimic-NC),mimic-NC + Hcy(mimic-NC transfecton+100 μmol/L Hcy),miR-144-3p mimic(transfected with miR-144-3p mimic),and miR-144-3p mimic + Hcy(miR-144-3p mimic transfection+100 μ mol/L Hcy),inhibitor-NC(transfected with inhibitor-NC),inhibitor-NC + Hcy(inhibitor-NC transfection + 100 μmol/L Hcy),miR-144-3p inhibitor(transfected with miR-144-3p inhibitor),and miR-144-3p inhibitor + Hcy(miR-144-3p inhibitor transfection + 100 μmol/L Hcy).Quantitative real-time PCR was used to detect the expression of miR-144-3p in liver tissue and hepatocytes.After transfection of miR-144-3p mimic or inhibitor,quantitative real-time PCR and western blot were used to detect the transfection efficiency of miR-144-3p and its effect on the expression of autophagy-related proteins LC3B and p62.The levels of alanine transferase and aspartate aminotransferase in hepatocyte supernatants were determined by enzyme linked immunosorbent assay.The correlation between the expression of miR-144-3 in hepatocyte and the levels of alanine transferase and aspartate aminotransferase in hepatocyte supernatants were analyzed by Pearson correlation analysis. RESULTS AND CONCLUSION:Compared with the Cbs+/+ group and control group,the expression of miR-144-3p in the liver tissue of the Cbs+/-group and in hepatocytes of the Hcy group was decreased(P<0.01).The expression of LC3B-Ⅱ/Ⅰ was decreased in hepatocyte after transfection of miR-144-3p mimic,while the protein expression of p62 was increased(P<0.01).The opposite results were obtained after transfection of miR-144-3p inhibitor(P<0.01).Compared with the mimic-NC group,the levels of alanine transferase and aspartate aminotransferase were decreased in the miR-144-3p mimic group(P<0.01),while the opposite results were obtained in the inhibitor-NC group(P<0.01).The expression of miR-144-3p in hepatocytes was negatively correlated with the levels of alanine transferase(P<0.01,r=-0.887 6)and aspartate aminotransferase(P<0.01,r=-0.829 9)in the supernatant of hepatocytes.To conclude,Hcy promotes hepatocyte autophagy by inhibiting the expression of miR-144-3p,which subsequently aggravates liver injury.

Objective Corruption is the most common cadaver phenomenon in forensic practice and an important basis for inferring time of death(PMI),but the definition of corruption degree and the construction of model inference models have always been difficult in the practice of forensic science.Methods In this study,the late postmortem phenomena were observed.Meanwhile,the microbial flora structure of gut and gravesoil and the nature of gravesoil were detected,for analyzing the changes before and after the key moment of abdominal rupture which naturally happened during the cadaver decay.Results The results found that from the macroscopic and microscopic levels,there were significant differences in cadaver decay,including microbial flora structure and gravesoil properties before and after the key moment of the natural abdominal rupture during cadaver decay.The phenomena are highly observable and can be accurately judged by forensic examinations,as well as related means in the field of biology and physiochemistry.In this study,this critical event was called Rupture Point.Conclusion The Rupture Point can be used as an important node for the assessment of cadaver decay degree in the practice of forensic medicine.It can be utilized for a cut-off point as well when constructing PMI inference models based on microbial flora structure changes.The accuracy of PMI inference models can be improved when the models were constructed in segments.

Objective To systematically evaluate the value of optical coherence tomography angiogra-phy (OCTA) for detecting the vessel density (VD) changes after open-angle glaucoma (OAG) surgery.Meth-ods The studies on OCTA for detecting the VD changes after OAG surgery were searched in the CNKI,WanFang,VIP,SinoMed,PubMed,Embase and Web of Science databases from the database establishment to May 2024.Literature screening,data extraction and risk of bias assessment of included studies were conducted independently by two reviewers.Descriptive analysis was adopoted for the systematic evaluation,the meta a-nalysis was conducted by using the R software and mean difference (MD) and its 95％CI were calculated.Re-sults A total of 13 studies were included,involving 472 patients with 500 tested eyes.The results of meta-a-nalysis showed that compared with pre-surgery,VD around the optic nerve head (ONH) and in nasal superi-or,temporal inferior,temporal superior,superior temporal and superior nasal regions at postoperative 6 months were significantly decreased.VD in the perimacular,perimacular superior hemisphere,permacular su-perior hemisphere,perimacular superior and permacular superior regions at postoperative 6 months were sig-nificantly increased.Conclusion OCTA could effectively detect the postoperative VD changes in the patients with OAG and predict postoperative visual function changes in glaucoma,and could serve as an effective test means for assessing the clinical treatment effect of the patients with OAG.

Objective:To investigate how reactive oxygen species(ROS)regulates the signal transduction of platelet activation and apoptosis,and to explore the relationship between platelet activation and apoptosis.Methods:Platelets were directly stimulated with thrombin or pretreated with ROS inhibitor N-acetylcysteine(NAC)before being stimulated with thrombin,and then flow cytometry was used to detect the effects of thrombin and NAC on P-selectin expression,αⅡbβ3 activation,mitochondrial membrane potential depolarization,phosphatidylserine(PS)externalization,ROS expression and platelet aggregation.Results:Thrombin could induce the production of ROS in platelets in a concentration-and time-dependent manner.0.01 U thrombin induced ROS-dependent high degree of integrin αⅡbβ3 activation,P-selectin expression,and platelet aggregation.The platelets induced by different concentration gradients of thrombin exhibited ROS-dependent mitochondrial membrane potential depolarization and PS externalization in platelets.After induction with thrombin for 30 min,the activation of integrin αⅡbβ3 in platelets reached its maximum level,and after 60 minutes,the depolarization of mitochondrial membrane potential in platelets reached its maximum level.However,the expression of P-selectin,depolarization of mitochondrial membrane potential,and platelet aggregation function were all inhibited to a certain extent when the platelets were pretreated with ROS inhibitor NAC and then induced with thrombin.Conclusion:When platelets are induced by thrombin,ROS first regulates the activation of platelets,and then regulates the apoptosis of platelets.Both platelet activation and apoptosis depend on the production of ROS in platelets,and the signals of activation and apoptosis occur orderly.Inhibiting the ROS signal in platelets can effectively inhibit the activation and apoptosis of platelets.

Using the"structure-process-outcome-institution"framework,this article analyzes the conceptual connotation and manifestation of primary care resilience.The mechanism by which digital technologies embedding improve organizational resilience of primary healthcare institution was elucidated;From the resilience perspective,an action framework for reshaping the primary healthcare system by digital technologies was constructed.Research has found that:1)Organizational resilience is the core of primary healthcare resilience.2)Digital technologies mainly promote coupling coordination between resource and organization through promoting change perception,knowledge absorption,and knowledge integration,improve organizational resilience of primary healthcare institution.3)There is a bidirectional interaction between the improvement of organizational resilience and reshaping primary healthcare system;4)The relevant departments should unify instrumental rationality,institutional rationality,and value rationality to establish the embedding,governance,and evaluation framework for digital technologies to reshape the primary healthcare system.

Objective:To construct a multi-sequence MRI radiomics combined with KRAS mutation nomogram model to predict the efficacy of pathological complete response (pCR) in patients with rectal cancer after neoadjuvant chemoradiotherapy.Methods:This study was a case-control study. A total of 126 patients with rectal cancer who were treated with neoadjuvant chemoradiotherapy in the Second Affiliated Hospital of Harbin Medical University from June 2020 to December 2023 were retrospectively collected. The pathological response of the postoperative specimens was graded, with 64 cases of pCR and 62 cases of non-pCR. KRAS gene detection was performed on the pathological tissues before neoadjuvant chemoradiotherapy. Among the patients, 34 cases had KRAS mutants and 92 cases had KRAS wild-types. The 126 patients were randomly divided into a training set and a validation set at a ratio of 8∶2 by the random number method, with 101 and 25 cases, respectively. The difference in KRAS mutation status between the pCR group and the non-pCR group was compared by the χ2 test. The radiomic features were extracted from the baseline T 2WI, diffusion-weighted imaging, and apparent diffusion coefficient images of the patients. The optimal radiomic features were screened out to establish the radiomics model. The radiomics-KRAS joint model was constructed by logistic regression, and a nomogram was drawn. The application efficiency of the model was evaluated by the receiver operating characteristic curve and calibration curve. Results:There was a statistically significant difference in KRAS mutation between the pCR group and the non-pCR group in the training set ( χ2=4.69, P=0.032). Ten radiomics features were screened out in MRI images to establish the radiomics model. In the training set and validation set, the areas under the curve (AUC) of KRAS mutation, radiomics model and radiomics-KRAS nomogram model for evaluating pCR after neoadjuvant chemoradiotherapy were 0.665 (95% CI 0.592-0.757), 0.746 (95% CI 0.651-0.895) and 0.818 (95% CI 0.742-0.934), respectively, and the AUCs of the validation set were 0.613 (95% CI 0.582-0.755), 0.738 (95% CI 0.627-0.839) and 0.833 (95% CI 0.768-0.961), respectively. The results of DeLong test showed that the AUC of radiomics-KRAS nomogram model was higher than that of KRAS mutation and radiomics model, and the difference was statistically significant ( Z=0.58, 0.63, P=0.024, 0.022 in the training set; Z=0.54, 0.61, P=0.018, 0.035 in the validation set). The calibration curve showed that the predicted probability of the radiomics-KRAS nomogram model was consistent with the actual probability. Conclusions:The multi-sequence MRI radiomics combined with the KRAS mutation nomogram model has the best efficacy in predicting pCR in patients with rectal cancer after neoadjuvant chemoradiotherapy, and has good practical application value.

Purpose: The aim of this study was to assess the risk of postoperative deep vein thrombosis (DVT) in breast cancer patients with coronavirus disease 2019 (COVID-19) to determine the optimal timing for surgery in the era of “post COVID-19 pandemic.” Methods: This prospective study included breast cancer patients who contracted COVID-19 and underwent surgery from December 20th, 2022, to March 20th, 2023 (n = 577). A control group comprised patients who underwent surgery from May 1st, 2019, to October 1st, 2019 (n = 327) and had not contracted COVID-19 prior to surgery. Patients were categorized based on the timing of their surgery relative to their COVID-19 infection. Data were analyzed using logistic regression. Results: Patients with COVID-19 had a higher incidence of postoperative DVT compared to those without COVID-19 (3.64% vs. 1.21%). Multivariable logistic regression analysis indicated that the timing of surgery was significantly associated with the risk of DVT (odds ratio [OR], 2.795; 95% confidence interval [CI], 0.692–11.278; p = 0.024). Patients who underwent surgery within two weeks of COVID-19 infection experienced the highest DVT rates (OR, 10.556; 95% CI, 1.095–303.313; p = 0.003). However, the incidence decreased to 2.85% when surgery was delayed until two weeks or more after infection. The median followup period was 10 months, all patients with DVT after surgery were recovered without serious complications or death. There were no adverse effects on subsequent anti-tumor therapy. Conclusion Caution is advised when performing breast cancer surgery within two weeks after a COVID-19 infection. Although the risk of DVT remains somewhat elevated even after two weeks, surgery can be considered safe given the urgency of treatment, favorable complication outcomes, and lack of impact on subsequent adjuvant therapy.

Stable isotope tracer metabolomics tracks and analyzes the whole metabolic process of the body through the tracer atoms, which belongs to the frontier technology in the field of biomedicine. This technology is of great significance and value for explaining the pathogenesis of diseases, finding biomarkers of diseases and drug action targets. Taking the mechanism of glucose catabolism disorder in depression as an example, this paper systematically expounds the stable isotope tracer metabolomics technology and its application. The research idea of stable isotope tracer metabolomics based on unmarked metabolomics was put forward, and the research strategy of biological significance interpretation from four dimensions of metabolite isotope abundance, key metabolic enzymes, metabolic flow direction and metabolite flow was given, which broke through the bottleneck of stable isotope tracer metabolomics research technology based on overall animal experiment, and provided scientific basis for the promotion and application of this technology.