L-phosphinothricin (L-PPT) is an efficient broad-spectrum herbicide. To realize the multi-enzyme catalytic preparation of L-PPT, we constructed an engineered strain Escherichia coli YM-1 for efficient expression of D-amino acid transaminase, which could catalyze the generation of the intermediate 2-oxo-4-[(hydroxymethylphosphonyl)] butyric acid (PPO) from D-phosphinothricin (D-PPT). In addition, E. coli pLS was constructed to co-express glutamate dehydrogenase and glucose dehydrogenase, which not only catalyzed the generation of L-PPT from PPO but also regenerated the coenzyme nicotinamide adenine dinucleotide phosphate (NADPH). A fed-batch fermentation process was then established for E. coli YM-1 and pLS, and the apparent activities of D-amino acid transaminase and glutamate dehydrogenase were increased by 22.68% and 100.82%, respectively, compared with those in shake flasks. The process parameters were optimized for the catalytic preparation of L-PPT by whole-cell cascade of E. coli YM-1 and pLS with D, L-PPT as the substrate. After reaction for 8 h, 91.36% conversion of D-PPT was achieved, and the enantiomeric excess of L-PPT reached 90.22%. The findings underpin the industrial production of L-PPT.
Escherichia coli/enzymology* ; Aminobutyrates/metabolism* ; Glutamate Dehydrogenase/biosynthesis* ; Glucose 1-Dehydrogenase/biosynthesis* ; Herbicides/metabolism* ; Multienzyme Complexes/metabolism* ; Transaminases/metabolism* ; Phosphinic Acids/metabolism*

Objective To investigate the expression of trophoblast cell-surface antigen 2(TROP2)in salivary ade-noid cystic carcinoma(SACC)in order to analyze its relationship with TROP2 expression and clinicopathological features,as well as to clarify the correlation between TROP2 expression and the prognosis of patients with SACC.Methods With approval from the ethics committee,the expression of TROP2 in 85 SACC and paracancer tissue sam-ples was detected by using the immunohistochemical method,and the relationship between TROP2 expression and clini-copathological characteristics was analyzed.The Kaplan-Meier method was used to analyze the relationship between TROP2 protein expression and 5-year disease-free survival(DFS)in 40 patients with SACC.Furthermore,the logistic re-gression model was used to analyze the prognostic factors of patients with SACC.Results The low or no expression rate of TROP2 in SACC tissues was significantly higher than that in paracancer tissues(P＜0.001).Low or no expres-sion of TROP2 was significantly positively correlated with tumor growth and clinical staging in patients with SACC(P＜0.05).Kaplan-Meier survival analysis showed that the DFS of patients with SACC with low or no expression of TROP2 protein was significantly lower than those of patients with high expression of TROP2 protein(P＜0.05),and the progno-sis was poor.The logistic regression model showed that low or no expression of TROP2 protein(OR=5.37;95%CI:1.03-28.08;P=0.046)and Ⅲ-Ⅳ clinical staging(OR=6.89;95%CI:1.37～34.77;P=0.019)were risk factors affect-ing the prognosis of patients with SACC.Conclusion Low or no expression of TROP2 protein in SACC tissues leads to poor prognosis of patients and is positively correlated with tumor growth and clinical staging.In addition,low or no ex-pression of TROP2 can be used as an independent prognostic risk factor for poor prognosis in patients with SACC,and TROP2 is a marker of poor prognosis in patients with SACC.

Objective:To explore the relationship between the triglyceride glucose (TyG) index and the risk of developing hypertension among rural Chinese adults.Methods:A prospective cohort study was conducted from 2007 to 2008, involving 20 194 adults selected through random cluster sampling from a rural community in Luoyang City, Henan Province. Follow-ups were carried out in 2013-2014 and 2018-2020. After excluding participants with hypertension at baseline, those with missing TyG index data, individuals who passed away during follow-up, and those with incomplete hypertension status at the second visit, 9 802 participants were included in the analysis. Baseline and follow-up assessments included questionnaire interviews, physical measurements (including blood pressure), and blood sample collection for fasting lipid and glucose levels. Participants were divided into four groups according to TyG index quartiles, and a modified Poisson regression model was utilized to assess the association between TyG index quartiles and hypertension risk.Results:The study cohort comprised 9 802 participants with a median age of 48 (39, 57) years, including 3 803 males (38.80%). Participants were distributed across TyG index quartiles as follows: TyG<8.2 group (2 224 individuals), TyG 8.2-8.5 group (2 653 individuals), TyG 8.6-8.9 (2 441 individuals), and TyG≥9.0 (2 484 individuals). Over a follow-up period of (11.1±1.3) years, 3 378 subjects developed hypertension, resulting in a cumulative incidence of 34.46% (3 378/9 802). The risk of hypertension increased with higher TyG index quartiles ( Ptrend<0.05). Compared to the TyG<8.2, the TyG 8.2-8.5 ( RR=1.11, 95% CI 1.01-1.22, P=0.023), TyG 8.6-8.9 ( RR=1.16, 95%CI 1.06-1.27, P=0.023), and TyG≥9.0 ( RR=1.20, 95%CI 1.10-1.31, P=0.023) exhibited increased hypertension risk after adjusting for age, gender, educational level, and other potential confounders. Subgroup analyses based on gender and age at baseline yielded results consistent with the main analysis. Conclusions:The TyG index is positively correlated with the risk of developing hypertension in the rural adult population.

Parkinson's disease is a neurodegenerative disease associated with abnormal copper metabolism in the brain,which leads to misfolding and aggregation of α-synuclein-copper complexes,which is an important pathological sign of Parkinson's disease.Copper metabolism,i.e.,cellular metabolic processes involving copper ions,is closely related to the pathogenesis of α-synuclein aggregation,dopamine metabolism,mitochondrial dysfunction,oxidative stress,and ferroptosis in Parkinson's disease.In this review,we summarize the molecular metabolic mechanism of copper toxicity by studying the pathological role of copper metabolism in Parkinson's disease,to support our further understanding of the mechanism of action and drug development.

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 compatible stability of esketamine hydrochloride,sufentanil citrate,butorphanol tartrate,and metoclopramide in 0.9%sodium chloride injection,and to provide a reference for the rational use of medication for postoperative analgesia.Methods The four drugs were compounded by simulating the clinical concentrations of the drugs,and the samples were taken at 0,4,8,12,24 and 48 h under light-shielded and light-exposed conditions at room temperature.The appearance,pH value,relative drug content,and insoluble particles were determined.Results The appearance of esketamine hydrochloride,sufentanil citrate,butorphanol tartrate,and metoclopramide concoction was clear at 48 h.The pH values were in the range of 4.69 to 4.79,and the relative drug content of the four drugs were in the range of 95%to 105%.The number of insoluble particles exceeded the specified range in the Chinese Pharmacopoeia(2020 edition)at 4 h and 8 h.Conclusions Under light-shielded and light-exposed conditions at room temperature,the appearance,pH value and relative drug content of the compounded solution remained stable for 48 h.However,the number of insoluble particles exceeded the specified standard.Therefore,it is not recommended to mix the above 4 drugs with 0.9%sodium chloride injection for use in analgesic pumps.

Objective:To elucidate the epidemiological characteristics and changing trends of liver failure in order to provide evidence-based strategies for prevention and treatment.Methods:The epidemiological information of inpatients with liver failure admitted and treated at Beijing You'an Hospital from 2012 to 2021 was retrospectively collected. The trend test was used to analyze age, gender, as well as the year-by-year changes in the underlying acute and chronic etiology of acute liver failure (ALF), sub-acute liver failure (SALF), acute-on-chronic liver failure (ACLF), and chronic liver failure (CLF).Results:During the study period, information on a total of 8512 inpatients, aged 51.3±13.5 years and mainly male (71.9%) with liver failure, was collected. The highest to lowest proportions of liver failure types were ACLF 4 023 (47.3%), CLF 3 571(42.0%), SALF 670 (7.9%), and ALF 248 (2.9%). The top five causes of liver failure in the overall population, accounting for 87.6% of the total, were hepatitis B 3 199 (37.58%), alcoholic liver disease 2 237 (26.28%), cryptogenic liver disease 906(10.61%), hepatitis B + alcoholic liver disease 603 (7.08%), drugs 488 (5.73%), The top three etiologies of patients with different types of liver failure were acute etiologies for acute liver failure (ALF), followed by drugs 107 (43.1%), hepatitis B 47(19.0%), and unknown etiology 36 (14.5%); sub-acute liver failure (SALF), followed by drugs 381(56.9%), unknown etiology 106 (15.8%), and sepsis 56 (8.4%); and acute-on-chronic liver failure (ACLF), followed by drugs 2 092(52.0%), alcoholic liver disease 813(20.2%), and cryptogenic liver disease 398(9.9%); and chronic etiologies for chronic liver failure (CLF), followed by alcoholic liver disease 1 410(39.5%), hepatitis B 1 028(28.8%), and cryptogenic liver disease 364(10.2%). Longitudinal analysis showed that the average age of patients with liver failure increased year by year, but the sex ratio trend did not change significantly, with male patients predominating throughout. The proportion of drug-induced liver failure in patients with ALF and SALF increased year by year, and the difference in the trend test was statistically significant ( P < 0.05). The proportion of patients with chronic etiologies of ACLF and CLF decreased year by year among hepatitis B, while the proportion of alcoholic liver disease, autoimmune liver disease, and cryptogenic liver disease increased year by year (the difference was statistically significant, P < 0.05). Conclusion:The etiological spectrum of liver failure is changing in our country. Although hepatitis B is still the main cause of liver failure, its proportion shows a decreasing trend year by year, with the exception of ACLF, which is no longer the primary etiology of other types of liver failure, while drug-induced liver disease, alcoholic liver disease, autoimmune liver disease, and cryptogenic liver disease are increasing year by year and will become the focus of liver disease prevention and treatment in the future.

Objective To analyze the risk factors of heart failure in patients with coronary heart disease(CHD),and to construct and verify a nomogram prediction model for the risk of heart failure in patients with CHD.Methods The clinical data of 453 patients with CHD who were hospitalized in the Second Affiliated Hospital of Shenyang Medical College from January to December 2022 were retrospectively analyzed,including 278 patients with CHD combined with heart failure and 175 patients without heart failure.The patients were divided into training group(318 cases)and validation group(135 cases)according to the ratio of 7:3.R software was applied to perform LASSO regression to screen the risk factors,and Logistic regression to establish a prediction model and construct a nomogram.The calibration curve and receiver operating characteristic(ROC)curve were used to evaluate the calibration and discrimination of the model.Results LASSO regression analysis ultimately screened five risk factors from 22 variables,and Logistic regression results showed that age,smoking,history of myocardial infarction,New York Heart Association(NYHA)cardiac function class Ⅳ,and left ventricular ejection fraction(LVEF)were all independent risk factors for heart failure in CHD patients(P＜0.05).The model formula was Z=-2.927+0.045 × age+0.886 × smoking+0.808 × history of myocardial infarction-2.829 × NYHA cardiac function class Ⅳ+0.037×LVFF.Internal validation of the model showed that area under the curve was 0.727(95％CI:0.588-0.752),the sensitivity was 40.4％,the specificity was 84.3％,and the Youden index was 0.247.According to the calibration curve,the predicted value of the calibration curve was highly consistent with the actual value,and the Brier score was 0.106.Conclusion The risk prediction model for heart failure in patients with CHD based on LASSO regression has good discrimination and prediction efficiency,which can be used as an evaluation tool for medical staff to predict the risk of patients.

Objective To analyze the impact of controlled hypotension (CH) by cerebral oxygen saturation (rSO₂) monitoring on brain protection and cognitive function in anesthetized patients. Methods A total of 200 patients undergoing rSO₂-monitored CH were enrolled. Patients were divided into normal group (n=137) and postoperative neurocognitive disorder (PND) group (n=63) based on whether they developed PND after surgery. Preoperative clinical data were collected. Univariate analysis was performed to identify factors influencing the occurrence of PND in rSO₂-monitored CH patients. Multivariate binary logistic regression analysis was used to screen for independent risk factors. A predictive model was constructed based on the identified independent risk factors, and its predictive value was evaluated using receiver operating characteristic (ROC) curve analysis. Results Age, intraoperative blood loss, vascular surgery, 20-minute rSO₂ monitoring values, 20-minute central venous pressure (CVP), history of hypertension, stroke and operative time were identified as factors affecting the occurrence of PND in rSO₂-monitored CH patients (P < 0.05). Independent risk factors for PND included age >55 years, high CVP during 20 minutes of surgery, low rSO₂ monitoring values during 20 minutes and undergoing vascular surgery (P < 0.05). ROC curve analysis showed that the area under the curve (AUC) for the predictive model was 0.855. Conclusion Clinically, the risk of PND in rSO₂-monitored CH patients (age >55 years, undergoing vascular surgery) can be reduced by controlling intraoperative CVP to minimize blood loss and by timely adjustment of treatment plans based on rSO₂ monitoring results.

Objective:To evaluate the right ventricular function in patients with dilated cardiomyopathy (DCM) by four-dimensional automatic right ventricular quantitative analysis (4D Auto RVQ), and compare with the right ventricular ejection fraction measured by cardiac magnetic resonance (CMR-RVEF), and to explore the clinical application value of 4D Auto RVQ technique in evaluating the right ventricular function of patients with DCM.Methods:A prospective study was conducted to select 52 patients with DCM who were treated in Fuwai Central China Cardiovascular Hospital of Zhengzhou University from March to October 2022 as DCM group, and 52 healthy volunteers were selected as the control group during the same period. The four-dimensional right ventricular ejection fraction (4D-RVEF), right ventricular stroke volume index (RVSVI), right ventricular end-diastolic volume index (RVEDVI), right ventricular end-systolic volume index (RVESVI), four-dimensional right ventricular basal diameter (4D-RVDd-base), four-dimensional right ventricular middle diameter (4D-RVDd-mid), four-dimensional right ventricular long axis diameter (4D-RVLd), four-dimensional tricuspid annular plane systolic excursion (4D-TAPSE) and four-dimensional right ventricular fractional area change (4D-RVFAC) were obtained by 4D Auto RVQ technique. The differences of the above parameters between DCM group and control group were compared.Pearson linear correlation analysis was used to evaluate the correlation between echocardiographic parameters and CMR-RVEF. The ROC curve was used to find the most sensitive parameters for evaluating right ventricular function, and the area under the ROC curve ( AUC ) was calculated and compared.Results:Compared with the control group, RVEDVI, RVESVI, 4D-RVDd-base and 4D-RVDd-mid in the DCM group were increased, and the absolute values of 4D-RVEF, 4D-TAPSE, 4D-RVFAC, right ventricular global longitudinal strain(RVGLS) and right ventricular free wall longitudinal strain(RVFWLS) were decreased (all P<0.05). Correlation analysis showed that 4D-RVEF was positively correlated with CMR-RVEF ( r=0.711, P<0.05). ROC curve analysis showed that 4D-RVEF was superior to other parameters in evaluating right ventricular function in DCM patients (AUC: 0.916). Conclusions:4D Auto RVQ technique can quantitatively evaluate right ventricular function in DCM patients. 4D-RVEF has a significant correlation with CMR-RVEF, and 4D-RVEF has the best efficacy in evaluating right ventricular function in DCM patients.