ObjectiveTo evaluate the feasibility of constructing tissue engineering cardiac patch with photooxidationfixed acellular bovine pericardium.MethodsFresh bovine pericardia were treated by dye-mediated photooxidation after decellularization.Some of them were seeded with bone marrow stromal cells(MSCs) isolated from male SD rats to construct cardiac patches.Myocardial infarction(MI) model was made in female SD rats by left anterior descending coronary ligation(LAD).One week later, the confirmed MI rats were divided into three groups randomly, group MI (n = 15)without any treatment; group P (n = 18) with photooxidated pericardia implantation ; group P + C (n = 18) with seeded pericardia implantation.A sham group (n = 10) was also performed with opening and closing chest twice only.The heart were explanted at 2 or 4 weeks after implantation, and examined histologically and immunohistochemically.The heart function was evaluated by echocardiography at 4 weeks before excising the rats.ResultsThere were no cells or cell debris remained in bovine pericardium tissue.The fiber structure became condensed after photooxidation.The seeded cells formed a continuous layer on the surface of the tissue.The pericardial degradation level and newly formed microvessel density were larger in group P + C than in group P after 2 [ (13.7 ±5.2)个/mm2 vs (7.1 ±3.1)个/mm2, P＜0.05]and4 [(22.6 ±4.9)个/mrn2 vs (14.1 ±5.3)个/mm2, P＜0.05]weeks.Four weeks after transplantation, cardiac echocardiography showed left ventricular ejection fraction(LVEF) was lower in group MI (44.8 ± 4.4) ％ and group P (48.4 ± 5.0) ％ compared with group P + C (49.3 ± 4.8) ％, left ventricular fractional shorterning(LVFS) was lower in group MI (18.0 ± 2.2) ％ and group P (19.8 ± 2.5) ％ compared with group P + C (20.4 ±2.5) ％, the difference between P + C and MI was significant.ConclusionTransplantation of the tissue engineered bovine pericardial patches with dye-mediated photooxidation can improve heart function in MI rats.This kind of patches demonstrates a promising prospect in the future.

Objective To explore the characteristic manifestations of breast malignant isodense masses using mammography. Methods 121 breast isodense masses with pathological confirmations were collected.Compared indicators with pathological findings were the tumor size,shape,edge,structure changes around the mass,axillary lymph nodes,skin changes,nipple changes,suspi-cious malignant calcification.χ2 test and Logistic regression analysis were used to evaluate the diagnostic values of each indicator.Re-sults In the 121 isodense masses,73 were benign,48 were malignant tumors.According to χ2 test analysis,factors impacted the nature of mass including:tumor morphology (χ2 =14.376,P =0.002),tumor edge (χ2 = 21.555,P =0.000),structure twisted surrounding the mass (χ2 =26.939,P =0.000),axillary lymph nodes (χ2 =1 6.285,P =0.000),skin thickening (χ2 =4.698,P =0.030).According to multivariate binary Logistic regression analysis,risk factors of the Logistic regression model included:edge infiltrating of mass (P =0.014),structure twisted surrounding the mass (P =0.003),axillary lymph nodes (P =0.026).Conclusion The characteristic manifestations of breast malignant isodense masses include edge infiltrating,structure twisted surrounding the mass,axillary lymph nodes.These manifestations are of great significance in differential diagnosis of breast isodense masses.

Objective To evaluate the necessity of prophylactic uterine artery embolization (UAE) before curettage in treatment of cesarean scar pregnancy (CSP).Methods A total of 142 patients with CSP were enrolled and divided into 3 groups according to Adler grading standard,including little vascularity (grade 0-Ⅰ,n=40),moderate vascularity (grade Ⅱ,n=41) and rich vascularity groups (grade Ⅲ,n=61).All patients were treated with curettage or prophylactic UAE before curettage.The differences of age,times of cesarean section,time to last cesarean section,intraoperative blood loss and success rate of therapy were compared between different treatment methods in each group.Results There was no statistical difference of age,times of cesarean section,time to last cesarean section,intraoperative blood loss and success rate of therapy between curettage and prophylactic UAE before curettage in little vascularity group and moderate vascularity group (all P＞0.05).Compared with curettage,the success rate of prophylactic UAE before curettage was higher and the intraoperative blood loss was lower in rich vascularity group (both P＜0.05).There was no statistical difference of age,times of cesarean section nor time to last cesarean section in rich vascularity group (all P＞0.05).Conclusion It is necessary to perform prophylactic UAE before curettage for cesarean scar pregnancy patient with rich vascularity,which is helpful to reduction of intraoperative blood loss.

Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-β-lactamase 1 (NDM-1) are a type of newly discovered antibioticresistant bacteria. The rapid pandemic spread of NDM-1 bacteria worldwide (spreading to India, Pakistan, Europe, America, and Chinese Taiwan) in less than 2 months characterizes these microbes as a potentially major global health problem. The drug resistance of NDM-1 bacteria is largely due to plasmids containing the blaNDM-1 gene shuttling through bacterial populations. The NDM-1 enzyme encoded by the blaNDM-1 gene hydrolyzes β-lactam antibiotics, allowing the bacteria to escape the action of antibiotics. Although the biological functions and structural features of NDM-1 have been proposed according to results from functional and structural investigation of its homologues, the precise molecular characteristics and mechanism of action of NDM-1 have not been clarified. Here, we report the three-dimensional structure of NDM-1 with two catalytic zinc ions in its active site. Biological and mass spectroscopy results revealed that D-captopril can effectively inhibit the enzymatic activity of NDM-1 by binding to its active site with high binding affinity. The unique features concerning the primary sequence and structural conformation of the active site distinguish NDM-1 from other reported metallo-β-lactamases (MBLs) and implicate its role in wide spectrum drug resistance. We also discuss the molecular mechanism of NDM-1 action and its essential role in the pandemic of drug-resistant NDM-1 bacteria. Our results will provide helpful information for future drug discovery targeting drug resistance caused by NDM-1 and related metallo-β-lactamases.
Amino Acid Sequence ; Anti-Bacterial Agents ; metabolism ; Binding Sites ; Captopril ; chemistry ; pharmacology ; Catalytic Domain ; Crystallography, X-Ray ; Drug Resistance, Bacterial ; Enterobacteriaceae ; enzymology ; Molecular Sequence Data ; Sequence Alignment ; Sequence Homology, Amino Acid ; beta-Lactamases ; chemistry ; metabolism

Objective To investigate the relationship between interventricular septum thickness(IVS) and renal function in patients with diabetes mellitus.Methods Two hundred and sixty-five patients of type 2 diabetes without dialysis were enrolled in a cross-sectional study.According to their IVS,the patients were divided into normal group (IVS≤ 11 mm) and higher IVS group (IVS ＞ 11 mm).All patients according to evaluated glomerular filtration rate (eGFR) level were divided into eGFR≥60 ml· min-1 · (1.73 m2) 1 group and eGFR ＜ 60 ml· min-1 · (1.73 m2)-1 group.The demographic characteristic,biochemical examination,eGFR,and proteinuria of different groups were compared.Pearson or spearman correlation was used to analyze the relationship between eGFR,IVS and other parameters.eGFR ＜ 60 ml · min-1 · (1.73 m2)-1 and IVS thickening were analyzed by binary logistic regression.Risk factors affect the prognosis of renal function in patients with diabetes mellitus were analyzed by Cox regression analysis.Results Compared with normal group,patients in the higher IVS group had higher systolic pressure (P=0.002),their level of Scr,BUN,24 h urinary protein were increased (all P ＜ 0.05),while the level of eGFR,albumin (ALB),hemoglobin (Hb) and fasting blood glucose were decreased (all P ＜ 0.05).The prevalence of hypertension was increased (81.16％ vs 58.67％,x2=11.273,P=0.001),and there was also a difference in the proportion of patients in each stage of CKD (x2=34.593,P ＜ 0.001).Correlation analysis showed that IVS was positively correlated with BMI,systolic BP,Scr,BUN,24 h urinary albumin,24 h urinary protein (all P ＜ 0.05),while negative correlation was observed between the thickened degree of IVS and Hb,albumin,eGFR and total calcium (all P ＜ 0.05).It's worth noting that IVS also correlated with history of hypertension and degree of renal injury (all P ＜ 0.01).Logistic regression analysis showed that longer duration of diabetes,higher systolic pressure and BUN were independent risk factors for eGFR ＜ 60 ml·min-1·(1.73 m2)-1 (all P ＜ 0.05),while higher Hb and Alb were independent protective factors for eGFR ＜ 60 ml· min-1· (1.73 m2)-1 (all P ＜ 0.05).Logistic regression analysis also showed that the baseline increased Scr was independent risk factor for interventricular thickening (P ＜ 0.05),while the increase of fasting blood-glucose was independent protective factor for interventricular thickening (P ＜ 0.05).Cox regression analysis showed that interventricular thickening was an independent risk factor in predicting the progression of type 2 diabetes (HR=1.396,95％ CI=1.098-1.774,P=0.006).Conclusion Interventricular septum thickness is closely related to the state of renal function,as well as is an independent risk factor to predict kidney function decline in patients with type 2 diabetes.

OBJECTIVE To set up normal ranges for indexes in embryo-fetal development toxicity studies in Sprague-Dawley(SD)rats and to establish a background database to provide reference for the embryo-fetal development toxicity evaluation of drugs.METHODS The data on embryonic develop-ment and fetal growth from embryo-fetal development toxicity studies(11 items)conducted by our center between 2013 and 2022 was statistically analyzed,involving 205 pregnant rats and 3037 fetuses in total,with the mean and standard deviation,coefficient of variation and 95%confidence interval calculated.The indexes included body mass,body mass gain and food consumption during pregnancy,pregnancy outcomes(pregnancy rate,average corpora lutea,average Implant sites,average live conceptuses,live conceptuse rate,resorption rate and dead conceptuse rate),fetal growth and development(fetal mass,placental mass and sex ratio),appearance abnormality rate,visceral abnormality rate,and skeletal abnormality rate.RESULTS The mass of pregnant rats trended up during gestation,with significant increases in the late period.Food consumption increased along with gestation.Caesarean section was conducted on gestation day 20,and the pregnancy rate was 93.2%.The average corpora lutea,Implant sites and live conceptuses were 18.0±3.2,15.9±2.8 and 14.8±3.0,respectively.The live conceptuse rate was 93.4%while the total dead embryo rate was 6.6%.The average mass of fetuses and placenta were respectively 3.6±0.3 and(0.6±0.3)g,and the fetal sex ratio(male/female)was 0.94.The incidence of fetal appearance abnormalities was about 0.2%,and that of soft tissue abnormalities was approximately 0.8%.The rate of skeletal abnormalities was about 1.2%,with higher incidence of non-ossification and incomplete ossification mostly identified on sternum and hyoid bone.The numbers of ossifications of metacarpal bones,metatarsal bones and sacrococcygeal vertebrae were 7.0±0.7,8.0±0.1 and 7.4±0.5,respectively.The rate of ossification of sternumⅠtoⅣwas higher,with an average of about 98.6%-99.9%.The ossification rates of sternum Ⅴ and Ⅵ were(68.0±28.4)%and(82.8±23.9)%.CONCLUSION The background database of indexes in the embryo-fetal development toxicity study on SD rats is established for our GLP laboratory,which provides reference for reproductive toxicity studies.

【Objective】 To investigate the effects of preoperative lipid metabolism level on the postoperative prognosis of non-muscular invasive bladder cancer (NMIBC). 【Methods】 Clinical data of NMIBC patients who underwent surgical treatment in our hospital during Mar.2014 and May 2021 were retrospectively analyzed. Based on receiver operating characteristic (ROC) curve, the optimal cutoff values of all lipid metabolism indicators were determined and patients were classified accordingly. The independent risk factors for postoperative recurrence were identified with Cox regression model. The survival was analyzed with Kaplan-Meier, and recurrence-free survival (RFS) was compared using log-rank tests. A recurrence risk prediction model was established based on the high-density lipoprotein (HDL) and other clinic pathological factors and the accuracy of prediction was evaluated with the area under the ROC curve (AUC). 【Results】 Cox multivariate analysis showed HDL, tumor number, tumor size and histological grade were independent risk factors for recurrence (P<0.05). Kaplan-Meier analysis showed that RFS was significantly longer in the high-HDL group than in the low-HDL group (P<0.001). Incorporating HDL, tumor number, tumor size, histological grade, and tumor stage into the recurrence risk model, the AUC was 0.706, and internal cross validation showed the AUC was 0.711. 【Conclusion】 Preoperative HDL is an independent risk factor affecting the RFS of patients with NMIBC, and combining it with clinic pathological factors will improve the prediction of tumor recurrence.

[Objective] To analyze factors influencing the postoperative progression-free survival (PFS) in patients with renal cell carcinoma (RCC), construct a nomogram model for predicting PFS, and compare it with other predictive models. [Methods] A retrospective analysis was conducted on the general and clinical data of 263 RCC patients who underwent surgery at the Department of Urology, the Second Affiliated Hospital of Xi'an Jiaotong University, during Apr.2014 and Nov.2021.Patients were divided into the progression group (n=34) and non-progression group (n=229). The data of the two groups were analyzed to identify prognostic variables associated with PFS, and a nomogram model was constructed.The performance of this model was compared with that of the University of California, Los Angeles Integrated Staging System (UISS) score, tumor staging, tumor size, tumor pathological grade, and tumor necrosis scoring system (SSIGN score), and Leibovich score by plotting receiver operating characteristic (ROC) curve and calculating the area under the curve (AUC). Calibration curve of the nomogram was used to validate the model's performance, and K-fold cross-validation was employed to assess its external validity. [Results] Multivariate Cox regression analysis revealed that age (HR=2.255, 95%CI: 1.032-4.926), T stage (HR=5.766, 95%CI: 2.351-14.142), pathological grade (HR=3.100, 95%CI: 1.445-6.651), and pathological necrosis (HR=2.656, 95%CI: 1.253-5.629) were independent risk factors of PFS (P<0.05). The nomogram model based on these four independent variables had AUCs (95%CI) of 0.750 (0.630-0.870), 0.803 (0.705-0.902), and 0.847 (0.757-0.937) for 1, 3, and 5 years, respectively, which were higher than those of UISS score, SSIGN score, and Leibovich score.The calibration curve of the nomogram showed good consistency between predicted and actual probabilities.In K-fold cross-validation, the average AUCs of the nomogram at 1, 3, and 5 years were 0.761, 0.808, and 0.842, indicating good external validity of the nomogram. [Conclusion] The nomogram based on age, T stage, pathological grade and pathological necrosis can accurately predict the risk of postoperative PFS in RCC patients at 1, 3, and 5 years, which can aid clinicians in the early identification of high-risk progression.

Protein phosphatase 2A (PP2A) accounts for the majority of total Ser/Thr phosphatase activities in most cell types and regulates many biological processes. PP2A holoenzymes contain a scaffold A subunit, a catalytic C subunit, and one of the regulatory/targeting B subunits. How the B subunit controls PP2A localization and substrate specificity, which is a crucial aspect of PP2A regulation, remains poorly understood. The kinetochore is a critical site for PP2A functioning, where PP2A orchestrates chromosome segregation through its interactions with BubR1. The PP2A-BubR1 interaction plays important roles in both spindle checkpoint silencing and stable microtubule-kinetochore attachment. Here we present the crystal structure of a PP2A B56-BubR1 complex, which demonstrates that a conserved BubR1 LxxIxE motif binds to the concave side of the B56 pseudo-HEAT repeats. The BubR1 motif binds to a groove formed between B56 HEAT repeats 3 and 4, which is quite distant from the B56 binding surface for PP2A catalytic C subunit and thus is unlikely to affect PP2A activity. In addition, the BubR1 binding site on B56 is far from the B56 binding site of shugoshin, another kinetochore PP2A-binding protein, and thus BubR1 and shugoshin can potentially interact with PP2A-B56 simultaneously. Our structural and biochemical analysis indicates that other proteins with the LxxIxE motif may also bind to the same PP2A B56 surface. Thus, our structure of the PP2A B56-BubR1 complex provides important insights into how the B56 subunit directs the recruitment of PP2A to specific targets.
Amino Acid Motifs ; Binding Sites ; Cell Cycle Proteins ; chemistry ; Crystallography, X-Ray ; Humans ; Multienzyme Complexes ; chemistry ; Protein Phosphatase 2 ; chemistry ; Protein Structure, Quaternary ; Protein-Serine-Threonine Kinases ; chemistry

Genome packaging is a fundamental process in a viral life cycle and a prime target of antiviral drugs. Herpesviruses use an ATP-driven packaging motor/terminase complex to translocate and cleave concatemeric dsDNA into procapsids but its molecular architecture and mechanism are unknown. We report atomic structures of a herpesvirus hexameric terminase complex in both the apo and ADP•BeF3-bound states. Each subunit of the hexameric ring comprises three components-the ATPase/terminase pUL15 and two regulator/fixer proteins, pUL28 and pUL33-unlike bacteriophage terminases. Distal to the nuclease domains, six ATPase domains form a central channel with conserved basic-patches conducive to DNA binding and trans-acting arginine fingers are essential to ATP hydrolysis and sequential DNA translocation. Rearrangement of the nuclease domains mediated by regulatory domains converts DNA translocation mode to cleavage mode. Our structures favor a sequential revolution model for DNA translocation and suggest mechanisms for concerted domain rearrangements leading to DNA cleavage.