Advances in the study of postpancreatectomy acute pancreatitis / 中华外科杂志

Postpancreatectomy acute pancreatitis (PPAP) is an acute inflammation of the remnant pancreas in the early postoperative period caused by a variety of factors. With the progress of related research,PPAP has been confirmed as an independent risk factor for many severe complications such as postoperative pancreatic fistula. In some cases, it progresses to necrotizing PPAP, increasing the risk of mortality. Currently, the International Study Group for Pancreatic Surgery has standardized and graded PPAP as an independent complication, taking into account factors including serum amylase, radiological features, and clinical impact. This review summarizes how the concept of PPAP was proposed, as well as the latest progress in the research related to its etiology, prognosis, prevention, and treatment. However, given the large heterogeneity of relevant studies and the fact that they were mostly retrospective, in the future, it is necessary to place more emphasis on PPAP and elucidate the problems through more standardized studies to optimize strategies for the prevention and management of complications after pancreatic surgery.

doxorubicin induces chronic heart failure in rats by regulating mitochondrial dynamics via drp1/fundc1 pathway / 中国药理学通报

Aim To investigate the damage degree of doxorubicin hydrochloride( DOX )on cardiac function in rats, and to explore its possible mechanism. Methods Experiment 1: SD rats( n=48 )were randomly divided into control group( normal saline ), DOX 1 group( DOX cumulative dose 12 mg·kg-1 ;intraperitoneal injection ), DOX 2 group( 15 mg·kg-1 ;)and DOX 3 group( 18 mg·kg-1 ;). Cardiac structure and cardiac function were detected by echocardiography. B-type natriuretic peptide( BNP )was detected by ELISA. The morphological changes of myocardium were observed by Hematoxylin-eosin( HE )staining. The optimal dose group( DOX 2 group )was selected comprehensively. Experiment 2: SD rats( n=36 )were randomly divided into control group( normal saline ), DOX 2 group(15 mg·kg-1)and DOX 2+Mdivi-1 group( 15 mg·kg-1+daily abdominal injection of Mdivi-1(1 mg ·kg-1 ;)). Western blot was used to detect the protein expression of myocardial mitochondrial dynamics. Results Compared with the control group, hearts in DOX groups were enlarged and the heart function was reduced. Under the microscope, hypertrophy of cardiac cells and loose arrangement of cardiac fibers were observed in DOX group, and the higher the cumulative dose of DOX in rats, the more severe the degree of heart failure and the higher the mortality rate of rats. Compared with control group, the expression of mitochondrial dynamin-related protein 1( DRP1 )and related signaling pathway protein FUN14 domain containing 1( FUNDC1 )in DOX 2 group increased. The expression of optic atrophy 1( OPA1 )decreased, the expression of FUNDC1 and DRP1 protein decreased, and the expression of OPA1 protein was enhanced after the use of mitochondrial dynamics inhibitor(Mdivi-1). Conclusions DOX can cause chronic heart failure, and the mechanism may be related to DRP1/FUNDC1 mediated mitochondrial fission and fusion.

Consistency analysis and clinical guiding significance of cytomegalovirus nucleic acid and antibody detections in patients with different clinical characteristics / 北京大学学报(医学版)

OBJECTIVE@#To investigate the consistency of cytomegalovirus deoxyribo nucleic acid (CMV-DNA) and immunoglobulin M (IgM) antibody detections in patients with different clinical characteristics and their guiding value for clinical practice.@*METHODS@#From December 2014 to November 2019, a total of 507 patients who were detected with both CMV-IgM and CMV-DNA were collected in Peking University International Hospital. Their general information, such as gender, age and clinical data, including the patient's diagnosis, medication, and outcome were also collected. The groups were stratified according to whether CMV-DNA was negative or positive, CMV-IgM was negative or positive, age, gender, and whether they received immunosuppressive therapy or not. The Pearson Chi-square test or Fisher's exact test was used for comparison of the rates between the groups. P < 0.05 means the difference is statisti-cally significant.@*RESULTS@#Of the 507 patients submitted for examination, 55 (10.85%) were positive for CMV-DNA, 74 (14.60%) were positive for CMV-IgM, and 20 (3.94%) were positive for both CMV-DNA and CMV-IgM. Of the 55 patients with CMV-DNA positive, 37 were male, accounting for 67.27%. In addition, 25 patients were older than 60 years, accounting for 45.45% and 33 patients received immunosuppressive therapy, accounting for 60%. The rates were higher than that of CMV-DNA negative group, 47.35% (P=0.005), 68.14% (P=0.043), 46.02% (P=0.050), respectively. Of the patients with both CMV-DNA and IgM positive, 45% received immunosuppressive threapy, which was lower than that of CMV-DNA positive but IgM negative patients (68.57%, P=0.086), and also lower than CMV-DNA negative but IgM positive patients (68.52%, P=0.064). In the patients with both CMV-DNA and IgM positive, 91.67% showed remission after receiving ganciclovir, whereas in the patients with CMV-DNA positive but IgM negative, the rate was only 60% (P=0.067).@*CONCLUSION@#CMV-IgM antibody detection is affected by age, gender, and immune status. It is not recommended to use CMV-IgM alone to determine CMV infection in patients with immunosuppressive status and those older than 60 years. CMV-DNA and CMV-IgM combined detection may help to predict patients' immune status and outcomes of antiviral therapy.

Effect of Shenmai Injection on Long-Term Prognosis of Patients with Chronic Heart Failure: A Multicenter, Large Sample Capacity, Long-Term Follow-Up Retrospective Cohort Study / 中国结合医学杂志

OBJECTIVE@#To explore the effect of Shenmai Injection (SMI) on the long-term prognosis of patients with chronic heart failure (CHF).@*METHODS@#The Hospital Information System was used to extract data of CHF patients, and the retrospective cohort study was conducted for analysis. In non-exposed group, standardized Western medicine treatment and Chinese patent medicine or decoction were applied without combination of SMI while in the exposed group, SMI were applied for more than 7 days. Evaluation indicators are followed with New York Heart Association functional classification (NYHA classification), left ventricular ejection fraction (LVEF), N-terminal brain natriuretic peptide precursor (NT-ProBNP), cardiogenic death and heart failure (HF) readmission. Statistical analysis includes Kaplan-Meier analysis and Cox regression which are used to explore the relationship between SMI and outcome events.@*RESULTS@#A total of 1,211 eligible CHF patients were involved and finally 1,047 patients were followed up successfully. After treatment, the cases of NYHA classification decline in the exposed and non-exposed groups accounted for 64.30% and 43.45%, respectively; the improvement values of LVEF were 8.89% and 7.91%, respectively; the improvement values of NT-ProBNP were 909 pg/mL and 735 pg/mL, respectively. After exposure on SMI, the rates of cardiogenic death and HF readmission reduced from 15.43% to 10.18% and 38.93% to 32.37%. According to Kaplan-Meier analysis, the log-rank P value of SMI and cardiogenic death was 0.014, while the counterpart of SMI and HF readmission was 0.025. Cox regression analysis indicated that for cardiogenic death, age, cardiomyopathy, diabetes, and NYHA classification were risk factors while β-blockers, aldosterone receptor antagonists, Chinese patent medicine/decoction and SMI were protective factors. Likewise, for HF readmission, age, cardiomyopathy, and NYHA classification were risk factors while SMI was a protective factor.@*CONCLUSION@#Combination with SMI on the standardized Western medicine treatment can effectively reduce cardiogenic mortality and readmission rate in CHF patients, and thereby improve the long-term prognosis.

Adult Age Estimation of CT Image Reconstruction of the Laryngeal Cartilages and Hyoid Bone Based on Data Mining / 法医学杂志

Objective To explore the feasibility of the CT image reconstruction of laryngeal cartilage and hyoid bone in adult age estimation using data mining methods. Methods The neck thin slice CT scans of 413 individuals aged 18 to <80 years were collected and divided into test set and train set, randomly. According to grading methods such as TURK et al., all samples were graded comprehensively. The process of thyroid cartilage ossification was divided into 6 stages, the process of cricoid cartilage ossification was divided into 5 stages, and the synosteosis between the greater horn of hyoid and hyoid body was divided into 3 stages. Multiple linear regression model, support vector regression model, and Bayesian ridge regression model were developed for adult age estimation by scikit-learn 0.17 machine learning kit （Python language）. Leave-one-out cross-validation and the test set were used to further evaluate performance of the models. Results All indicators were moderately or poorly associated with age. The model with the highest accuracy in male age estimation was the support vector regression model, with a mean absolute error of 8.67 years, much higher than the other two models. The model with the highest accuracy in female adult age estimation was the support vector regression model, with a mean absolute error of 12.69 years, but its accuracy differences with the other two models had no statistical significance. Conclusion Data mining technology can improve the accuracy of adult age estimation, but the accuracy of adult age estimation based on laryngeal cartilage and hyoid bone is still not satisfactory, so it should be combined with other indicators in practice.

Effect of acidic culture conditions on the proliferation, apoptosis, and migration ability of human tongue squamous cell carcinoma cells and its related mechanism / 华西口腔医学杂志

OBJECTIVES@#This study aims to explore the effect of acidic culture conditions on the proliferation, apoptosis, and migration ability of human tongue squamous cell carcinoma SCC15 and CAL27 cells and its potential molecular mechanism.@*METHODS@#After acidic culture for different periods, methyl thiazolyl tetrazolium (MTT) method was adop-ted to detect the cell proliferation of SCC15 and CAL27. Flow cytometry was employed to detect the apoptosis level of SCC15 and CAL27 cells. The migration ability of SCC15 and CAL27 after acidic culture was detected by scratch hea-ling test. Real-time fluorescence quantitative polymerase chain reaction (FQ-PCR) was used to detect the mRNA expression of cyclooxygenase 2 (COX-2) and survivin in SCC15 and CAL27 cells after acidic culture.@*RESULTS@#After culture for 24 h under acidic microenvironment, SCC15 and CAL27 cells grew rapidly and reached the stationary phase after adjustment for 3 days. The apoptosis levels of SCC15 and CAL27 cells decreased after acidic culture, but the most significant reduction occurred after 6 h of acidic culture. The scratch healing rates of SCC15 and CAL27 cells increased after acidic culture. The results of FQ-PCR showed that the mRNA expression levels of COX-2 and survivin in SCC15 and CAL27 cells increased after acidic culture.@*CONCLUSIONS@#Extracellular acidic microenvironment can inhibit the apoptosis of tongue squamous carcinoma cells, promote their migration, and induce more adaptable and malignant tongue squamous carcinoma cells. The mechanism may be related to COX-2 and survivin and their signal pathways.

Experimental Research Progress of Replenishing Qi and Activating Blood Circulation Traditional Chinese Medicine on Mitochondrial Quality Control in Treatment of Chronic Heart Failure / 中国实验方剂学杂志

Heart failure is a complex clinical syndrome，which is the final result of compensatory failure of heart injury caused by various reasons. Long-term persistent cardiac stress leads to mitochondrial dysfunction，which in turn further damages cardiomyocytes and leads to disease progression. Timely removal of damaged mitochondria in cardiomyocytes and maintaining a good living environment of viable mitochondria is not only an effective means to protect cardiomyocytes，but also a new way to prevent and treat heart failure and ventricular remodeling. Mitochondrial quality control is a series of cellular activities for mitochondria to maintain their structural and functional stability，including oxidative stress response，regulation of mitochondrial dynamics，mitochondrial autophagy，intracellular calcium regulation and so on. Traditional Chinese medicine（TCM） mostly uses drugs of replenishing Qi and activating blood circulation in the treatment of chronic heart failure，and Qi and mitochondria are similar in function. According to TCM，the performance of the body as "static，descending and inhibitory" in the case of Qi deficiency can also be compared with the energy defect of mitochondria. The classical method of tonifying qi and activating blood circulation in TCM can be applied here. In recent years，TCM takes mitochondria as the target and carries out many related experimental studies from the point of view of myocardial energy supply. It is found that Chinese herbs for replenishing Qi and activating blood circulation can participate in regulating the quality control mechanism of intracellular mitochondria with multiple targets and links. It is proved by experiments that Chinese herbs for replenishing Qi and activating blood circulation can exert myocardial protective effect through this mechanism.

Evaluation of continuous metabolic syndrome score as a screening tool for metabolic syndrome in Xinjiang urban population aged 15-18 years / 中国学校卫生

Objective@#The purpose of the present study was to evaluate of continuous metabolic syndrome score (cMetS) in screening metabolic syndrome (MetS) and to determine the cut-off values in a representative sample of Xinjiang population aged 15 to 18 years old.@*Methods@#A stratified cluster sampling was used to select participants aged 15-18 years from 13 cities in Xinjiang. cMetS was calculated by summing up the Zscores of standardized waist circumference, mean arterial pressure, high-density lipoprotein, triglyceride, and fasting blood glucose by age and gender.@*Results@#Totally 16.3% of subjects were overweight, and 5.2% were obese. The proportion of overweight and obesity in males was significantly higher than that in females (18.1% vs 13.8%)(6.0% vs. 4.1%)(χ2=15.36，7.89，P<0.05). The prevalence of total MetS was 6.1%, with 6.6% and 5.4% for men and women, respectively. There was a correlation between cMetS and MetS components, and the average cMetS value increased with increasing MetS component(P<0.05). The total cut-off value of cMetS was 0.99 (sensitivity 68.0%, specificity 80.7%), and the area under the ROC curve was 84.9%. The cMetS scores for boys and girls were 0.80 and 1.48, respectively.@*Conclusion@#Compared with MetS, cMetS shows more accuracy in screening MetS among youth aged 15-18 years in both gender.

Estimation of Early Postmortem Interval of Asphyxial Death Rats at Different Ambient Temperatures by GC-MS-Based Metabolomics / 法医学杂志

Objective To establish the orthogonal partial least square （OPLS） model for the estimation of early postmortem interval （PMI） of asphyxial death rats in four ambient temperatures based on gas chromatography-mass spectrometry （GC-MS） metabolomics. Methods The 96 rats were divided into four temperature groups （5 ℃, 15 ℃, 25 ℃ and 35 ℃）. Each temperature group was further divided into 3 h, 6 h, 12 h and 24 h after death, and 6 other rats were taken as the control group. The cardiac blood was collected at the set time points for the four temperature groups and 0 h after death for the control group for the metabolomics analysis by GC-MS. By OPLS analysis, the variable importance in projection （VIP）>1 and the result of Kruskal-Wallis test P<0.001 were used to screen out the differential metabolite related to PMIs in the cardiac blood of rats of different temperature groups. Then OPLS regression models of different temperature groups were established with these metabolites. At the same time, a prediction group for investigating the prediction ability of these models was set up. Results Through the analysis of OPLS, 18, 15, 24 and 30 differential metabolites （including organic acids, amino acids, sugars and lipids） were screened out from the rats in groups of 5 ℃, 15 ℃, 25 ℃ and 35 ℃, respectively. The prediction results of the four temperature group models showed that the prediction deviation of 5 ℃ model was larger than that of other groups. The prediction results of other temperature groups were satisfactory. Conclusion There are some differences in the changes of metabolites in cardiac blood of rats at different ambient temperatures. The influence of ambient temperature should be investigated in the study of PMI estimation by metabolomics, which may improve the accuracy of PMI estimation.

Research Progress of Adult Age Determination with Imaging Methods / 法医学杂志

Adult age determination plays an important role in individual identification, criminal investigation and social welfare. The most popular adult age determination indicators are pubic symphysis, iliac auricular surface, costal cartilage, cranial sutures, teeth, laryngeal cartilage, etc. In recent years, with the progress of CT imaging and 3D reconstruction technology, the adult age determination study gradually has transferred from a time-consuming general observation of bones with complex pre-processing in the past to the non-destructive, convenient, time-saving and easy to store image analysis technology. To explore more accurate, rapid and convenient adult age determination methods, multiple imaging methods and artificial intelligence have been applied in adult age determination. This paper reviews the common methods and research progress of adult age determination at home and abroad, infers the development direction of adult age determination, in order to provide reference for the improvement and optimization of forensic adult age determination.

GeneXpert MTB/RIF evaluated in diagnosis of pulmonary tuberculosis / 上海预防医学

Objective To evaluate GeneXpert MTB/RIF in diagnosis of pulmonary tuberculosis by comparing the lab results of diagnosed patients. Methods A total of 97 diagnosed pulmonary tuberculosis patients were enrolled from July 2017 to June 2018.Sputum smear microscopy (Ziehl-Neelsen stain), sputum culture (MGIT liquid culture) and Xpert MTB/RIF were conducted in all patients.Drug susceptibility test and strain identification by PNB were done for culture positive sputum samples.Consistency rate was calculated. Results In terms of M.tuberculosis detection, sensitivity and specificity of GeneXpert were 93.44% and 55.55%, respectively, compared with bacteriological examination (consistency rate 79.38%).Consistency rate of GeneXpert and PNB is 94.55%.In terms of RIF resistance test, sensitivity and specificity of GeneXpert were 66.67% and 98.08%, respectively, compared with phenotypic drug-susceptibility testing (consistency rate 96.36%). Conclusion GeneXpert MTB/RIF can be utilized in combination with smear microscopy and liquid culture to diagnose more etiologically positive patients, and can spot RIF resistance patients early.But strain identification and drug susceptibility test are still needed for individualized therapy and optimal treatment outcome.

GeneXpert MTB/RIF evaluated in diagnosis of pulmonary tuberculosis / 上海预防医学

Objective To evaluate GeneXpert MTB/RIF in diagnosis of pulmonary tuberculosis by comparing the lab results of diagnosed patients. Methods A total of 97 diagnosed pulmonary tuberculosis patients were enrolled from July 2017 to June 2018.Sputum smear microscopy (Ziehl-Neelsen stain), sputum culture (MGIT liquid culture) and Xpert MTB/RIF were conducted in all patients.Drug susceptibility test and strain identification by PNB were done for culture positive sputum samples.Consistency rate was calculated. Results In terms of M.tuberculosis detection, sensitivity and specificity of GeneXpert were 93.44% and 55.55%, respectively, compared with bacteriological examination (consistency rate 79.38%).Consistency rate of GeneXpert and PNB is 94.55%.In terms of RIF resistance test, sensitivity and specificity of GeneXpert were 66.67% and 98.08%, respectively, compared with phenotypic drug-susceptibility testing (consistency rate 96.36%). Conclusion GeneXpert MTB/RIF can be utilized in combination with smear microscopy and liquid culture to diagnose more etiologically positive patients, and can spot RIF resistance patients early.But strain identification and drug susceptibility test are still needed for individualized therapy and optimal treatment outcome.

Predictive value of cardiac biomarkers of low cardiac output in children undergoing congenital heart surgery / 中华胸心血管外科杂志

Objective:To assess the predictive value of atrial natriuretic peptide, b-type natriuretic peptide(BNP), cardiac troponin I(cTn-I) and central venose oxygen saturation(ScvO 2)as indicators of low cardiac output syndrome(LCOS) in children with congenital heart disease undergoing cardiopulmonary bypass(CPB). Methods:After corrective surgery for congenital heart disease under CPB, 70 children(aged 5 days to 160 months) were enrolled in a prospective observational pilot study during 1-year period from April 2017 to March 2018. The patients were classified according to whether they developed low cardiac output syndrome. Biomarker levels were measured at 2, 12, 24, and 48 h post-CPB. The clinical data and outcome variables were analyzed by a multiple logistic regression model. Results:Twenty-two(31.4%) patients developed low cardiac output syndrome(group 1) and the remaining 48(68.6%) patients were included in group 2. cTn-I levels >13 ng/ml at 2 hours after CPB( OR=40.2, 95% CI: 9.4-171.4, P<0.001) and ScvO 2 levels<0.37 at 12 hours following CPB( OR=124.7, 95% CI: 28.7-538.2, P<0.001) were independent predictors of low cardiac output syndrome. Conclusion:Our results suggest that cTn-I at 2 h and ScvO 2 levels at 12 h post-CPB are evident early predictors of low cardiac output syndrome. This predictive capacity is, moreover, reinforced when cTn-I combined with ScvO 2 following CPB. These 2 cardiac biomarkers would aid in therapeutic decision-making in clinical practice and would also enable clinicians to modify the type of support to be used in the pediatric intensive care unit.

Surgical treatment of non-functional pancreatic neuroendocrine neoplasms / 中国实用外科杂志

The incidence of non-functional pancreatic neuroendocrine neoplasms(NF-pNENs)constantly increases due to the development of imaging techniques and the popularity of routine medical examination.WHO classification system,ENETS and AJCC grading systems,widely used in clinical practice,are independent prognostic factors.According to the G grading system,NF-pNENs are classified into benign,low-grade malignant and high-grade malignant tumors.Operative indications and treatments are absolutely different for each subgroup.Lymph node metastasis closely correlates with the position and size of tumor,lymphovascular invasion and Ki-67 index.Pre-operative determination of the presence of lymph node metastasis provides significant instructions for the choice of surgery since it indicates early tumor relapse and metastasis.The advance of ultrasoundguide biopsy provides more sensitive indictors for preoperative pathological grade and lymph node metastasis.Both domestic and foreign guidelines consider the tumor size as the critical factors for surgery.For those NF-pNENs2 cm,even with local vascular and organs invasion,a routine pancreatic surgery is recommended(distal pancreatectomy or pancreatic duodenectomy according to the tumor position).Lymph node sampling or regional lymphadenectomy should be routinely performed during surgeries.For those with liver metastasis,surgical resection,locoregional ablative therapy or liver transplantation is suggested according to the situation of metastatic sites.

Diagnosis,treatment and etiology of hepatic infarction and abscess after pancreaticoduodenal surgery / 中国实用外科杂志

OBJECTIVE: To explore the causes and treatment of hepatic infarction and abscessafter pancreaticoduodenal surgery.METHODS: The clinical data of 11 cases of hepatic infarction or abscess after pancreaticoduodenal surgery in Peking Union Medical College Hospital between January 2012 and December 2018 were analyzed retrospectively.RESULTS: A total of 11 patients were diagnosed of hepatic infarction or abscess after PD.The overall mortality rate was27.3%(3 of 11 patients).54.5%(6/11)had biliary fistula.Of the 11 patients,7 had proper hepatic artery and right accessory hepatic artery occlusion or stenosis,1 had abdominal trunk root stenosis before operation,and 3 had PV stenosis.Enterococcus and Klebsiella were the organisms most frequently cultured,and fungi were also the common pathogens.Antibiotics and selective percutaneous drainage were the main means of treatment.CONCLUSION: Ischemia of hepatic artery and portal vein after PD is the main cause of liver infarction and liver abscess.Biliary fistula and multiple pathogenic bacteria are often associated with high mortality.

Visually Isoattenuating Pancreatic Acinar Cell Carcinoma:Report of One Case / 中国医学科学院学报

Acinar cell carcinoma of pancreas(ACCP)is a rare pancreatic exocrine tumor that accounts for about 1% of pancreatic tumors. The typical imaging manifestations of ACCP are as follows:(1)the tumor is large in volume,partially or completely exophytic;(2)complete or incomplete capsule is visible with thin linear enhancement;(3)CT density and MRI signal:plain CT images reveals that the tumors have similar or slightly hypodense densities relative to the adjacent normal pancreas,the solid part of ACCP has low to intermediate signal intensity on T1WI and intermediate to high signal intensity on T2WI compared with the surrounding normal pancreas;(4)pattern of enhancement:tumors exhibit heterogeneous enhancement and it is less than that in the surrounding normal pancreas;(5)fissure-like,swirling necrosis that may be a characteristic change of tumor;(6)pancreatic and biliary duct dilatation is rare;(7)adjacent organs and blood vessels around the pancreas may be invaded;(8)distant metastasis of liver and other parts may be observed;(9)PET-CT shows high FDG uptake. An ACCP patient with atypical imaging manifestations was treated in Peking Union Medical College Hospital from November 2015 to August 2017. The lesion manifested iso-enhancement and many imaging examinations failed to find the tumor. The patient ultimately underwent surgery and diagnosed as ACCP by pathology.

The anomalies of choroidal and retinal blood flow in cone-rod dystrophy / 眼科新进展

Objective To study the alteration of blood flow indexes of ophthalmic artery (OA),central retinal artery (CRA) and posterior ciliary artery (PCA) of the patients with cone-rod dystrophy (CRD).Methods The color doppler flow imaging was used in 50 CRD patients (100 eyes,CRD group) and 90 controls (180 eyes,control group) to measure the peak systolic velocity (PSV),end diastolic velocity (EDV),timeaveraged maximum velocity (TAMV),pulsatility index (PI) and resistance index (RI)in OA,CRA and PCA,respectively,and the data was obtained and analyzed statistically by one-sample t test to compare the alteration of these parameters between the CRD group and control group.Results The TAMV of OA was (14.29 ±3.88)cm · s-1 in CRD group and (12.44 ± 3.64) cm · s-1 in the control group,and the difference was statistically significant (P ＜0.05);meanwhile,the PI was 1.75 ±0.42 in CRD group and 2.02 ±0.71 in the control group,and the difference was statistically significant (P ＜0.05).Moreover,the PSV,EDV,TAMV and PI,RI of CRA was (4.60 ± 1.29) cm · s-1,(1.61 ±0.41)cm · s-1,(2.59 ±0.67)cm · s-1 and 1.11 ±0.31,0.63 ±0.10 in CRD group,respectively,and (10.82 ± 2.97) cm · s-1,(3.28 ± 1.11) cm · s-1,(5.50 ± 2.06)cm · s-1 and 1.48 ±0.49,0.71 ±0.08,in the control group,accordingly,and the differences were statistically significant (all P ＜ 0.05).Furthermore,the PSV,EDV,TAMV and PI,RI of PCA was (7.36 ± 2.18) cm · s-1,(2.28 ± 0.82) cm · s-1,(3.99 ± 1.22)cm · s-1 and 1.28 ± 0.37,0.68 ± 0.09 in CRD group,respectively,and (11.61 ± 3.41)cm · s-1,(3.34±1.25)cm · s-1,(5.83 ±1.91)cm · s-1 and 1.49 ±0.43,0.70 ±0.09 in the control group,accordingly,and the differences were statistically significant (all P ＜0.05).Conclusion Hemodynamic unusual alterations of OA,CRA and PCA in CRD patients suggest there is the correlation between the ocular blood supply and the pathological process of CRD,which remains to be observed further.

Investigation of Protonated and Lithiated Leucine-Enkephalin by Hydrogen/Deuterium Exchange and Theoretical Calculations / 分析化学

Differences of protonated and lithiated leucine-enkephalin(LE) were investigated by hydrogen deuterium exchange-mass spectrometry(HDX-MS) combined with quantum chemistry calculation. The results revealed that the protonated ions possessed very high product yield with all hydrogen atoms being exchanged, while the reaction of lithiated LE stopped after exchanging five hydrogen atoms in the same experimental conditions. The different HDX behaviours probably indicated their conformational differences. To further clarify the experimental results, the most stable conformations of protonated and lithiated leucine-enkephalin were calculated by density functional theory. It was found that terminal amino group was the most thermodynamically stable protonation site,while Li+in coordination of four carbonyl oxygen atoms formed the most favourable lithiated LE. The reaction field reduction of lithium LE was probably due to the less acidity of hydrogen atoms and the increasing rigid conformation change induced by lithium ion.

Effect of lipoxin A4 on lipopolysaccharide-induced oxidant stress in human renal tubular epithelial cells and possible mechanisms / 实用医学杂志

Objective The study aimed to investigate the effect of lipoxin A4 (LXA4) on lipopolysaccharide (LPS)?induced oxidant stress in human renal tubular epithelial cells (HK2 cells) and possible underlying mecha?nisms. MethodsHK2 cells were divided into three groups: Control ,LPS and LPS+LXA4 groups. After cells were treated with indicated conditions,morphological changes were observed. The expressions of Nrf2 were detected by immunofluorescence and cells were collected for RT?PCR experiments.Results HK2 cells seemed disrupted and necrotic with the administration of LPS. However ,LXA4 could prevent cells from injury induced by LPS. LPS decreased Nrf2 expression and promoted it to translocate to cytoplasm ,while LXA4 could increase its expression and promote it to translocate to nucleus. Moreover ,LPS could decrease Nrf2 and its downstream molecule mRNA expressions,but LXA4 could reverse this effect. Conclusion Our results demonstrated that LXA4 effectively inhibit?ed HK2 cell oxidant stress via Nrf2 pathway.

Performance verification of diluted thrombin time assay for detecting Dabigatran level in plasma / 临床检验杂志

Objective To evaluate the performance of diluted thrombin time (dTT) assay for detecting Dabigatran levels and observe whether this assay may meet the requirements of clinical laboratory.Methods According to EP15-A2,EP6-A,EP7-A and C-24 documents of the Clinical and Laboratory Standards Institute (CLSI),the precision,trueness,analytical measurement range,carryover rate and anti-biological interference of dTT assay were evaluated and the stability of specimen for dTT assay was observed.Results Both the within-day and between-day coefficient of variation (CV) of dTT assay for detecting Dabigatran levels were consistent with manufacturer's stated CV.Compared with target values of Dabigatran,the relative bias of 3 levels of proficiency test materials from College of American Pathologists (CAP) were less than 10％.The results meet linear verification when Dabigatran concentration was between 30.92 and 249.13 ng/mL.The carryover rate was-0.84％.There was no interference for Dabigatran levels by dTT assay for detecting Dabigatran when Hb≤3 g/L,triglyceride≤873 mg/dL,heparin≤2.2 IU/mL and FDP≤29 mg/L.The results of stability showed that plasma specimens for dTT could not be stored at room temperature more than 4 hours,at 4 ℃ more than 4 days,at-20 ℃ exceed 1 month,while at-80℃ the plasma specimens could be stored at least 6 months for dTT assay.Conclusion The precision,trueness,analytical measurement range,carryover rate,anti-biological interference of dTT assay may meet the requirement of clinical laboratory.The stability of the specimen can fulfill the clinical requirements.