[Impact of COVID-19 on primary percutaneous coronary intervention in patients with acute ST segment elevation myocardial infarction in Beijing]

Objective: To investigate the impact of COVID-19 on treatment of patients with acute ST segment elevation myocardial infarction(STEMI) undergoing primary percutaneous coronary intervention(PPCI). Methods: This was a multicenter retrospective study. STEMI patients undergoing PPCI from January 1, 2019 to December 31, 2021 were selected, based on the data of Xinnaolvsetongdao App. Clinical data and treatment time indicators, including symptom to first medical contact (S-FMC), symptom to door (StoD), first medical contact to ECG (FMC-ECG), first medical contact to guide wire (FMC-W), door to balloon (DtoB) and total ischemic time in 2019, 2020 and 2021 were compared. STEMI patients aged<60 years were sub-grouped as the young and middle-aged group, and STEMI patients aged≥60 years were sub-grouped as the elderly group. Results: A total of 7 435 (3 305 in 2019, 1 796 in 2020 and 2 334 in 2021) STEMI patients aged (59.6±12.6) years undergoing PPCI were included in this analysis. There were 5 990 males. For STEMI patients with PPCI in 2019, 2020 and 2021, FMC-ECG was 3 (1, 5) min, 3(1, 7) min and 4 (1, 7) min. FMC-W was 73 (56, 87) min, 78 (62, 95) min and 77 (62, 87) min. DtoB was 73 (56, 85) min, 78 (62, 95) min and 77 (62, 86) min. Total ischemic time was 189 (130, 273) min, 196 (138, 295) min and 209 (143, 276) min. FMC-ECG, FMC-W, DtoB and total ischemic time were longer in 2020 and 2021 than in 2019 (all P<0.05). The proportions of patients with FMC-ECG≤10 min (88.4% (1 588/1 796) vs. 92.7% (3 064/3 305), P<0.05), FMC-W≤120 min (87.9% (1 579/1796) vs. 91.7% (3 030/3 305), P<0.05) and DtoB≤90 min (72.3% (1 298/1 796) vs. 80.8% (2 672/3 305), P<0.05) were lower in 2020 than in 2019, whereas no differences were observed in the proportions of patients with FMC-ECG≤10 min (91.3% (2 131/2 334) vs. 92.7% (3 064/3 305), P=0.054), FMC-W≤120 min (92.0% (2 148/2 334) vs. 91.7% (3 030/3 305), P=0.635) and DtoB≤90 min (80.0% (1 867/2 334) vs. 80.8% (2 672/3 305), P=0.424) in 2021 compared with 2019. In the subgroup analysis, the proportions of patients with FMC-ECG≤10 min, FMC-W≤120 min and DtoB≤90 min were lower in the elderly group than in young and middle-aged group in 2019 (all P<0.05). The proportions of patients with FMC-W≤120 min and DtoB≤90 min were lower in the elderly group than in young and middle-aged group in 2021(all P<0.05). No differences were observed in the proportions of patients with FMC-ECG≤10 min, FMC-W≤120 min and DtoB≤90 min between the two group in 2020 (all P>0.05). Conclusions: Affected by the COVID-19, there is a reduction in the number of PPCI cases and treatment delays in STEMI patients, especially in the elderly. After adjusting the treatment strategy and widely applying the Xinnaolvsetongdao APP, the above indicators are significantly improved in 2021 as compared with 2020.

[Investigation of extrauterine growth restriction in very preterm infants in Chinese neonatal intensive care units]

Objective: To comprehensively assess the current status of extrauterine growth restriction (EUGR) in very preterm infants (VPI) and its associated factors in Chinese neonatal intensive care units (NICU). Methods: In this cohort study, 6 179 preterm infants born at <32 weeks' gestation were included, who were admitted to 57 hospitals in the China Neonatal Network in 2019 and hospitalized for ≥7 days. EUGR was evaluated by a cross-sectional definition (weight at discharge<10th percentile for postmenstrual age), a longitudinal definition (decline in weight Z score>1 from birth to discharge), and weight growth velocity. The comparison between infants with and without EUGR was conducted by t-test, Mann-Whitney U test or χ2 test as appropriate. Multivariable Logistic regression models were used to evaluate associations between EUGR with different definitions and maternal and neonatal factors, clinical practices, and neonatal morbidities. Results: A total of 6 179 VPI were enrolled in the study, with a gestational age of (29.8±1.5) weeks and birth weight of (1 365±304) g; 56.2% (3 474) of them were male. Among them, 48.4% (2 992 VPI) were cross-sectional EUGR and 74.9% (4 628 VPI) were longitudinal EUGR. Z score of weight was (0.13±0.78) at birth and decrease to (-1.35±0.99) at discharge. The weight growth velocity was 10.13 (8.42, 11.66) g/(kg·d). Multivariate Logistic regression analysis showed that among the influential factors that could be intervened after birth, late attainment of full enteral feeds (ORadjust=1.01, 95%CI 1.01-1.02, P<0.001; ORadjust=1.01, 95%CI 1.01-1.02, P<0.001), necrotizing enterocolitis≥Ⅱstage (ORadjust=2.64, 95%CI 1.60-4.35, P<0.001; ORadjust=1.62, 95%CI 1.10-2.40, P<0.001) and patent ductus arteriosus (ORadjust=1.94, 95%CI 1.50-2.51, P<0.001; ORadjust=1.63, 95%CI 1.29-2.06, P<0.001) were all associated with increased risks of both cross-sectional and longitudinal EUGR. In addition, late initiation of enteral feeds (ORadjust=1.06, 95%CI 1.02-1.09, P=0.020) and respiratory distress syndrome (ORadjust=1.45, 95%CI 1.24-1.69, P<0.001) were all associated with cross-sectional EUGR. Breast milk feeding (ORadjust=1.33, 95%CI 1.05-1.68, P<0.001) was associated with a higher risk of longitudinal EUGR. Conclusions: The incidence of EUGR in VPI in China is high. Some modifiable risk factors provide priorities to improve postnatal growth for VPI. Nutritional management of VPI and the efforts to decrease the incidence of complications are still the focus of clinical management in China.

[Etiology, diagnosis and treatment strategy of dental therapy-related subcutaneous emphysema]

Subcutaneous emphysema is the local tissue swelling caused by the gas entering the subcutaneous tissue through the tissue gap. Although subcutaneous emphysema is usually a nonfatal and self-limited disease, in severe cases, the gas may spread to the neck, mediastinum and chest, resulting in mediastinal emphysema and other serious complications. This article reviews the etiology, pathogenesis, clinical manifestations, diagnosis, differential diagnosis of subcutaneous emphysema related to dental therapy,and operations that may cause subcutaneous emphysema in stomatology department,as well as the treatment and prognosis of subcutaneous emphysema, with a view to providing some references for dentists.

[Diagnosis and treatment strategy of permanent tooth developmental disturbances caused by primary tooth trauma]

The trauma to primary tooth may lead to developmental disturbances of permanent tooth. Because the traumatic events are often forgotten as accurred earlier, the timely diagnosis and intervention treatment are not conducted, resulting in aesthetic and functional disorders. This paper systematically elaborates the types of developmental disturbances in permanent tooth after traumatic injuries to the primary predecessor, and the etiology, mechanism, related factors as well as the treatment options, in order to provide references for the prevention of serious complications in inherited permanent tooth caused by primary tooth trauma.

[Immunoprotective effect of recombinant peptidyl-prolyl cis-trans isomerase from Babesia microti against B. microti infection in mice]

OBJECTIVE

To evaluate the immunoprotective effect of active immunization with recombinant peptidyl-prolyl cis-trans isomerase from Babesia microti against B. microti infection in mice.

METHODS

Female BALB/c mice at 6 weeks of age, each weighing approximately 20 g, were divided into the recombinant protein immunization group, the infection control group and the normal control group, of 25, 18, 15 mice in each group, respectively. Mice in the recombinant protein immunization group were given active immunization with recombinant BmPPIase protein, and 18 mice with the highest antibody titers were intraperitoneally injected with 100 μL of B. microti-infected whole blood 2 weeks after the last immunization. Mice in the infection control group were intraperitoneally injected with 100 μL of B. microti-infected whole blood, while 15 mice in the normal control group received no treatment. Blood samples were collected from mice in the recombinant protein immunization group and the infection control group on days 0 to 30 post-immunization for detection of B. microti infection, and blood samples were collected on days 0, 7, 14, 21, and 28 post-immunization for routine blood tests with a blood cell analyzer and for detection of serum cytokines using cytometric bead array.

RESULTS

Anti-BmPPIase antibodies were detected in 25 mice in the recombinant protein immunization group 2 weeks after the last immunization, with titers of 5 × 10³ to 8 × 10⁴. B. microti infection rate peaked in mice in both the recombinant protein immunization and the infection control group on day 7 post-immunization, with positive infection rates of 13.3% and 50.0%, and there were significant differences between the two groups in terms of B. microti infection rate on days 3 (χ²= 113.18, P < 0.01), 5 (χ² = 475.22, P < 0.01), 7 (χ² = 465.98, P < 0.01) and 9 post-infection (χ²= 18.71, P < 0.01), while the B. microti infection rate tended to be 0 in both groups on day 11 post-immunization. Routine blood tests showed higher red blood cell counts [(5.30 ± 0.50) × 10¹² to (9.87 ± 0.24) × 10¹² counts/L)] and hemoglobin levels [(89.67 ± 22.80) to (148.60 ± 3.05) g/L)] in the recombinant protein immunization group than in the infection control group on days 0 to 28 post-immunization. Cytometric bead array detected higher serum interferon-γ [(748.59 ± 17.56) to (3 858.28 ± 1 049.10) fg/mL], tumor necrosis factor-α [(6 687.34 ± 1 016.64) to (12 708.13 ± 1 629.79) fg/mL], interleukin (IL)-6 [(611.05 ± 75.60) to (6 852.68 ± 1 554.00) fg/mL] and IL-17a [(167.68 ± 185.00) to (10 849.27 ± 355.40) fg/mL] and lower IL-10 levels [(247.65 ± 138.00) to (18 787.20 ± 2 830.22) fg/mL] in the recombinant protein immunization group than in the infection control group during the study period.

CONCLUSIONS

Recombinant BmPPIase protein induces up-regulation of interferon-γ, tumor necrosis factor-α and presents a high immunoprotective activity against B. microti infection in mice, which is a potential vaccine candidate protein.

[Establishment and validation of a preoperative nomogram model for predicting the risk of hepatocellular carcinoma with microvascular invasion]

Objective: To establish and validate a nomogram model for predicting the risk of microvascular invasion(MVI) in hepatocellular carcinoma. Methods: The clinical data of 210 patients with hepatocellular carcinoma who underwent hepatectomy at Department of Hepatobiliary and Pancreatic Surgery,the Affiliated Hospital of Qingdao University from January 2013 to October 2021 were retrospectively analyzed. There were 169 males and 41 females, aged(M(IQR)) 57(12)years(range:30 to 80 years). The patients were divided into model group(the first 170 cases) and validation group(the last 40 cases) according to visit time. Based on the clinical data of the model group,rank-sum test and multivariate Logistic regression analysis were used to screen out the independent related factors of MVI. R software was used to establish a nomogram model to predict the preoperative MVI risk of hepatocellular carcinoma,and the validation group data were used for external validation. Results: Based on the modeling group data,the receiver operating characteristic curve was used to determine that cut-off value of DeRitis ratio,γ-glutamyltransferase(GGT) concentration,the inverse number of activated peripheral blood T cell ratio (-aPBTLR) and the maximum tumor diameter for predicting MVI, which was 0.95((area under curve, AUC)=0.634, 95%CI: 0.549 to 0.719), 38.2 U/L(AUC=0.604, 95%CI: 0.518 to 0.689),-6.05%(AUC=0.660, 95%CI: 0.578 to 0.742),4 cm(AUC=0.618, 95%CI: 0.533 to 0.703), respectively. Univariate and multivariate Logistic regression analysis showed that DeRitis≥0.95,GGT concentration ≥38.2 U/L,-aPBTLR>-6.05% and the maximum tumor diameter ≥4 cm were independent related factors for MVI in hepatocellular carcinoma patients(all P<0.05). The nomogram prediction model based on the above four factors established by R software has good prediction efficiency. The C-index was 0.758 and 0.751 in the model group and the validation group,respectively. Decision curve analysis and clinical impact curve showed that the nomogram model had good clinical benefits. Conclusions: DeRitis ratio,serum GGT concentration,-aPBTLR and the maximum tumor diameter are valuable factors for preoperative prediction of hepatocellular carcinoma with MVI. A relatively reliable nomogram prediction model could be established on them.

[Application value of metagenomic next-generation sequencing for infectious pathogens in patients receiving allogeneic hematopoietic stem cell transplantation]

Objective: To investigate the application value of Metagenomic Next-Generation sequencing (mNGS) in infectious patients after allogeneic hematopoietic stem cell transplantation(allo-HSCT). Methods: Patients suspected with local or systemic infections were retrospectively included after allo-HSCT in our department from April 2019 to November 2020. Pathogenic microorganisms were tested by mNGS in samples from peripheral blood, cerebrospinal fluid, alveolar lavage Liquid, abscess, etc. Other diagnostic methods such as bacterial/fungal culture, viral PCR detection were simultaneously explored comparing with mNGS results. Results: A total of 112 samples in 83 patients were detected by mNGS, and 34 pathogenic microorganisms were determined. Among these positive samples, 11 strains of bacteria (17 times) with the most common Escherichia coli (4/17) were reported. There were 7 strains of fungi (10 times) detected with primary Candida albicans (7/29). Although arvovirus 30.2% (39/129) were predominantly detected, its diagnostic relevance with infections was not definite. Other pathogenic viruses including cytomegalovirus (CMV) 25.6% (33/129) and Epstein Barr virus (EBV) 14.0% (18/129)were of significance. Comparing with golden diagnostic criteria, the sensitivity of mNGS was 86.5%, and specificity was 45.0%. Regarding single pathogen infection, the consistency of mNGS and conventional methods was 82.9% (29/35), while it was 16/17 in combination infections. Conclusion: mNGS could be a potential method to determine pathogens in patients suspected with infections after allo-HSCT.

[Percutaneous biliary stent combined with brachytherapy for malignant obstructive jaundice: a multicenter retrospective controlled study]

Objective: To investigate the efficacy, safety and prognostic factors of percutaneous biliary stent combined with iodine-125 seed chain brachytherapy (radiotherapy) in the treatment of malignant obstructive jaundice. Methods: Data of 107 cases with malignant obstructive jaundice treated with percutaneous biliary stent implantation from January 2017 to December 2020 were retrospectively analyzed. Among them, 58 cases received biliary stent combined with iodne-125 seed chain brachytherapy (study group), and 49 cases received biliary stent implantation (control group). The changes of bilirubin, stent patency time, complications, overall survival (OS) and prognostic factors were analyzed in both groups. Results: The incidence of complications in the study group and the control group were 17.2% and 18.3% respectively, and the difference was not statistically significant (P=0.974). Serum total bilirubin levels were decreased significantly in both groups at one month after surgery (P<0.001). Postoperative stent patency time was significantly better in the study group (10.0±1.6 months) (95% CI: 8.2～12.5) than that in the control group (5.2±0.4 months) (95% CI: 4.1～6.0, P<0.001). The median OS was longer in the study group (11.2±1.8 months) (95% CI: 9.2～12.8) than that in the control group (8.0±1.1 months) (95% CI: 8.0～12.8, P<0.001). Multivariate analysis result showed that stent combined with brachytherapy (HR=0.08, 95% CI:0.04～0.15, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.27, 95% CI:0.15~0.49, P<0.001) were independent risk factors affecting the patency of biliary stents. Preoperative percutaneous transhepatic biliary drainage (HR=0.46, 95%CI:0.28～0.74, P=0.002), stent combined with brachytherapy (HR=0.23, 95%CI:0.14～0.39, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.37, 95%CI:0.22～0.61, P<0.001) were independent risk factors affecting OS. Conclusion: Percutaneous biliary stent combined with brachytherapy is safe and effective in the treatment of malignant obstructive jaundice, which can significantly prolong the patency time of biliary stent and the survival time of patients.

[Status of HVPG clinical application in China in 2021]

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

[Effects and mechanism of hydrogen peroxide pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells]

Objective: To investigate the effects and mechanism of hydrogen peroxide (HP) pretreatment with low molarity on oxidative stress induced apoptosis of mouse bone marrow mesenchymal stem cells (BMSCs). Methods: The experimental research methods were used. BMSCs were isolated and cultured from two 2-week-old male BALB/c mice by the whole bone marrow culture method. The 3rd-7th passages of cells in logarithmic growth phase were used for the experiments after identification. According to the random number table (the same grouping method below), the cells were divided into 0 μmol/L HP group (without HP, the same below), 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. The apoptosis rate was detected by flow cytometry (n=4) after 24 hours of culture. The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, and 100 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively. After 24 hours of culture, the protein expressions of B-lymphoma-2 (Bcl-2) and Bcl-2-related X protein (Bax) were detected by Western blotting, and the Bcl-2/Bax ratio was calculated (n=3). The cells were divided into 0 μmol/L HP group, 25 μmol/L HP group, 50 μmol/L HP group, 100 μmol/L HP group, 200 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respectively. After 24 hours of culture, the protein expressions of glycogen synthase kinase-3β (GSK-3β) and phosphorylated GSK-3β (p-GSK-3β) were detected by Western blotting (n=3). The cells were divided into 0 μmol/L HP group, 50 μmol/L HP group, and 300 μmol/L HP group in which cells were treated by the corresponding final molarity of HP, respeclively, and HP pretreatment group with 50 μmol/L HP being added in advance for 12 h and then 300 μmol/L HP being added. After 24 hours of culture, the morphology and growth of cells were observed by inverted fluorescence microscopy (non-fluorescent condition) and immunofluorescence method, the apoptosis rate was detected by flow cytometry, the protein expressions of Bcl-2, Bax, cysteine aspartic acid specific protease-3 (caspase-3), caspase-9, cleavage caspase-3, cleavage caspase-9, GSK-3β, and p-GSK-3β were detected by Western blotting, and the Bcl-2/Bax ratio was calculated, with all the number of samples being 3. Data were statistically analyzed with one-way analysis of variance and Bonferroni test. Results: After 24 hours of culture, compared with that in 0 μmol/L HP group, the apoptosis rate of cells did not change significantly in 25 μmol/L HP group, 50 μmol/L HP group, or 100 μmol/L HP group (P>0.05) but increased significantly in 150 μmol/L HP group, 200 μmol/L HP group, 250 μmol/L HP group, and 300 μmol/L HP group (P<0.01). After 24 hours of culture, compared with that in 0 μmol/L HP group, the Bcl-2/Bax ratio of cells increased significantly in 25 μmol/L HP group and 50 μmol/L HP group (P<0.05 or P<0.01) but decreased significantly in 100 µmol/L HP group (P<0.05). After 24 hours of culture, compared with those in 0 μmol/L HP group, the protein expression of GSK-3β in cells showed no significant change in 25 μmol/L HP group and 50 μmol/L HP group (P>0.05), the protein expressions of p-GSK-3β in cells significantly increased in 25 μmol/L HP group and 50 μmol/L HP group (P<0.01), the protein expressions of GSK-3β and p-GSK-3β in cells in 100 μmol/L HP group showed no significant change (P>0.05), the protein expressions of GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group were significantly increased (P<0.05). but the protein expression of p-GSK-3β in cells in 200 μmol/L HP group and 300 μmol/L HP group was significantly decreased (P<0.05). After 24 hours of culture, the morphology and growth of cells in 0 μmol/L HP group and 50 μmol/L HP group were similar and normal; in contrast, the cells in 300 µmol/L HP group became smaller and round, with the cell protrusions being shorter or disappeared, the nucleus being cavitated, and the cell abscission being increased significantly; the morphology of most cells in HP pretreatment group was normal, with the shedding of cells being less than that in 300 µmol/L HP group, and the morphology of nucleus being normal. After 24 hours of culture, the protein expression of caspase-9 was similar among the four groups (P>0.05). Compared with that in 0 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 50 μmol/L HP group showed no significant changes (P>0.05), the Bcl-2/Bax ratio of cells in 50 μmol/L HP group increased significantly (P<0.05), the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells in 300 μmol/L HP group were significantly increased (P<0.01), while the Bcl-2/Bax ratio of cells in 300 μmol/L HP group was significantly decreased (P<0.05). Compared with those in 300 μmol/L HP group, the apoptosis rate and the protein expressions of cleavage caspase-9, caspase-3, and cleavage caspase-3 of cells were significantly decreased in HP pretreatment group (P<0.05 or P<0.01), while the Bcl-2/Bax ratio of cells was significantly increased in HP pretreatment group (P<0.01). After 24 hours of culture, the protein expressions of GSK-3β and p-GSK-3β of cells in 0 μmol/L HP group, 50 μmol/L HP group, 300 μmol/L HP group, and HP pretreatment group were 1.09±0.14, 0.62±0.17, 1.35±0.21, 0.74±0.34, 0.68±0.03, 0.85±0.08, 0.38±0.10, and 0.54±0.09, respectively. Compared with those in 0 μmol/L HP group, the protein expression of p-GSK-3β of cells was significantly increased in 50 μmol/L HP group (P<0.05) but significantly decreased in 300 μmol/L HP group (P<0.01), while the protein expression of GSK-3β of cells was significantly increased in 300 μmol/L HP group (P<0.05). Compared with those in 300 μmol/L HP group, the protein expression of GSK-3β of cells was significantly decreased in HP pretreatment group (P<0.01), while the protein expression of p-GSK-3β of cells was significantly increased in HP pretreatment group (P<0.01). Conclusions: The molarity of 50 μmol/L may be the optimal molarity of HP to pretreat mouse BMSCs, and 50 μmol/L HP pretreatment can antagonize mitochondrial pathway of oxidative stress induced apoptosis by inhibiting the activity of GSK-3β.

Application Prospects and Prospect of Metabolomics in the Identification of Sudden Cardiac Death

Abstract

In cases of sudden death, the prevention of sudden cardiac death and the analysis of the cause of death after sudden cardiac death have always been a difficult problem. Therefore, clinical research and forensic pathological identification of sudden cardiac death are of great significance. In recent years, metabolomics has gradually developed into a popular field of life science research. The detection of "metabolic fingerprints" of biological fluids can provide an important basis for early diagnosis of diseases and the discovery of potential biomarkers. This article reviews the current research status of sudden cardiac death and the research on metabolomics of cardiovascular diseases that is closely related to sudden cardiac death and analyzes the application prospects of metabolomics in the identification of the cause of sudden cardiac death.

Correlation between the Polymorphism of Coagulation-Related Genes and Lower Extremity Deep Venous Thrombosis

Abstract

Objective To investigate the correlation between the polymorphism of 4 coagulation-related genes, rs1799963 （coagulation factor V gene Leiden）, rs6025 （prothrombin gene G20210A）, rs1042579 （thrombomodulin protein gene c.1418C>T） and rs1801131 （methylenetetrahydroflate reductase gene） and lower extremity deep venous thrombosis （LEDVT）. Methods The 4 genotypes mentioned above of 150 LEDVT patients and 153 healthy controls were detected by the kompetitive allele specific polymerase chain reaction （KASP）, then related blood biochemical indicators were collected, binary Logistic regression was established to screen the independent risk factors of LEDVT, and the correlation between polymorphism of 4 coagulation-related genes and LEDVT and its indicators under different genetic modes after adjusting confounding factors were analyzed. Results Five variables, D-dimer, fibrinogen degradation product, homocysteine, sex and age might be the risk factors of LEDVT. These variables were put into 4 genetic inheritance models, and adjusted in binary Logistic regression. The results suggested that the mutations of rs1042579 were correlated with LEDVT under dominant inheritance mode. Conclusion The gene polymorphism of rs1799963, rs6025 and rs1801131 has no significant correlation with the formation of LEDVT. The gene polymorphism of rs1042579 plays a role under dominant inheritance mode, and might be an independent risk factor for formation of LEDVT.

[Application of endobronchial ultrasound in children: an analysis of 4 cases]

Objective: To investigate the feasibility, clinical efficacy and safety of endobronchial ultasound (EBUS) in children. Methods: The radiological features, EBUS images, pathological results and intraoperative and postoperative complications of 3 cases who underwent EBUS examination and 1 case who underwent EBUS guided transbronchial needle aspiration (EBUS-TBNA) were retrospectively analyzed. Results: Among the 4 cases, 2 were males and 2 were females, with the onset age of 7.4-9.2 years. The child who underwent successful EBUS-TBNA was presented with fever and diagnosed with mediastinal lymphadenopathy before the operation, and the postoperative pathology indicated histiocytic necrotic lymphadenitis (HNL). The other 3 children diagnosed with primary airway tumors, whose pre-operative CT imaging found no infiltration in extra-bronchial structures, had the masses resected through EBUS. According to postoperative pathological findings, two were diagnosed with mucoepidermoid carcinoma and one with bronchial leiomyoma. The lesions were located at the opening of the right main bronchus in 1 case and at the main airway in 2 cases. EBUS showed abnormal echogenicity of the tracheal wall in the 3 cases, including hyperechoic area in the water capsule and mucous layer, relatively hypoechoic area in the submucosal smooth muscle layer, hyperechoic area in the inner cartilage layer, hypoechoic in the cartilage layer and hyperechoic in the outer cartilage layer. In one case, structural disorder of the submucosal smooth muscle layer and partial disruption of the cartilage layer of the tracheal wall were found at the lesion site, while the other 2 cases had intact tracheal wall structure. There were no postoperative complications such as pneumothorax or hemoptysis in the 4 children. Conclusion: EBUS is a safe and feasible technique for evaluating mediastinal lymph node enlargement and the degree of airway wall infiltration in primary airway tumor.

[Role of interleukin-6 in human umbilical vein endothelial cell to mesenchymal cell transformation]

Objective: To observe the effect of interleukin-6 (IL-6) on the phenotype and function of human umbilical vein endothelial cells (HUVECs) and explore the role of IL-6 in the process of endothelial-to-mesenchymal transition (EndMT). Methods: The experimental research method was used. Fresh umbilical cord discarded after normal maternal delivery was collected. On the second day of the primary cell isolation and cultivation, the cell morphology was observed under inverted phase contrast microscope. HUVECs of the 4th passage were identified by immunofluorescence method, and 2 batches of HUVECs ofthe 3rd to 5th passages were used for the subsequent experiments. The first batch of cells were divided into 6 groups according to the random number table (the same below): blank control group, 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group. The second batch of cells were divided into 4 groups: blank control group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group,and 50 ng/mL IL-6 group; the cells in blank control group was cultured with complete culture medium only, while the cells in the other groups were added with IL-6 of the corresponding final mass concentrations.Cells from the 1st batch were cultured for 72 hours after grouping, the morphology of HUVECS in the 6 groups was observed under inverted phase contrast microscope. At 72 h after grouping culture, the positive expressions of coagulation factor Ⅷ and α vascular smooth muscle actin (α-SMA) in HUVECs in the 6 groups were detected by immunofluorescence method, and the ratio of the number of double positive cells to the number of coagulation factor Ⅷ positive cells (the ratio of double positive cells for short) was calculated, with 6 samples per group; mRNA expression levels of vascular endothelial cadherin and α-SMA of HUVECs in 6 groups were detected by reverse transcription-polymerase chain reaction, with 3 samples per group.Cells from the 2nd batch were cultured 72 hours after grouping, the protein expression levels of vascular endothelial cadherin, α-SMA, and type Ⅰ collagen in the 4 groups were detected by Western blotting, with 3 samples per group. Data were statistically analyzed with one-way analysis of variance and Bonferroni correction. Results: On the 2nd day after isolation and cultivation, the primary cells were in short spindle shape or polygon, cells of the 4th passage were identified as HUVECs by immunofluorescence method. At 72 hours of culture after grouping, the cells from the 1st batch in the 6 groups changed to long spindle shape morphologically along with the increase of IL-6 concentration, the intercellular connections decreased or disappeared with the gap between cells becoming larger. At 72 h after grouping culture, compared with that inblank control group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 5 ng/mL IL-6 group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the ratio of double positive cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly increased (P<0.01); the ratio of double positive cells in 100 ng/mL IL-6 group was significantly increased compared with those in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly decreased (P<0.01 or P<0.05); compared with that in 5 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 10 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of α-SMA of cells in 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6, group, and 100 ng/mL IL-6 group were significantly increased (P<0.05 or P<0.01). Cells from the 2nd batch were cultured for 72 hours after grouping. Compared with 1.391±0.026 in blank control group, the protein expressions of vascular endothelial cadherin of cells in 10 ng/mL IL-6 group (1.185±0.063), in 25 ng/mL IL-6 group (0.717±0.078), and in 50 ng/mL IL-6 group (0.239±0.064) were significantly decreased (P<0.05); compared with that in 10 ng/mL IL-6 group, the protein expressions of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly decreased (P<0.01); compared with that in 25 ng/mL IL-6 group, the protein expression of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group was significantly decreased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expression levels of α-SMA of cells in 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, and 50 ng/mL IL-6 group were significantly increased (P<0.01); compared with that in 10 ng/mL IL-6 group, the protein expression levels of α-SMA of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expressions of type Ⅰ collagen of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (P<0.05). Conclusions: After IL-6 treatment, the phenotype and function of HUVECS showed the characteristics of mesenchymal cells in a concentration-dependent manner. The inflammatory factor can promote the process of EndMT, and become one of the important factors regulating the mechanism of tissue fibrosis.

[Pediatric nasal neuroglial heterotopia: report of 13 cases]

Objective: To summarize clinical features and our experience of the diagnosis and treatment of pediatric nasal neuroglial heterotopia (NGH). Methods: Clinical data of 13 nasal NGH patients in Beijing Children's Hospital from August 2014 to October 2019 were retrospectively reviewed, including 9 boys and 4 girls, aged from 1 to 38 months with median age of 5 months. Radiological workups and excision of nasal NGH under general anesthesia were performed for all patients. B ultra-sound and MRI were performed for all external and mixed lesions, while ultra-low-dose CT scan and MRI for all intranasal type. Surgical approaches were dependent on location and extent of the lesions according to radiographic workup, including extranasal or transnasal endoscopic approach. Patients were followed up regularly after operation to evaluate the effect. Initial presentation, locations, imaging findings, surgical approaches and follow-up results were analyzed through descriptive statistical method. Results: Eight nasal NGH patients presented with an internal nasal mass and nasal obstruction, which belonged to intranasal type. Three patients presented with an external nasal mass which belonged to extranasal type and 2 patients had mixed lesions. The sites included nasal dorsum (n=5), anterior to the middle turbinate (n=5) and olfactory cleft (n=3). Surgical resections were done through median rhinotomy approach (n=5) or transnasal endoscopic approach (n=8). All the operations were successful and no complication occurred. All cases were followed up from 3 to 65 months. No recurrence was encountered. Conclusions: Nasal NGH is a rare lesion with atypical clinical presentation. Preoperative imaging including CT scan and MRI is essential for evaluation of the location, extent of the disease and for making the surgical plan. Treatment requires complete surgical excision.

[Operative efficacy of 13 malignant uterine tumors after Cf-252 intracavitary irradiation]

Objective: To investigate the surgical therapeutic efficacy of uterine tumors patients underwent Cf-252 neutron intra-cavity and external radiotherapy, and evaluate the application value of Cf-252 neutron radiotherapy. Methods: Thirteen cases of uterine tumor with local suspicious lesions or poor prognostic factors after CF-252 neutron intracavity and external radiotherapy were treated with surgery. Among them, 12 cases underwent extrafascial hysterectomy, 1 case underwent extensive hysterectomy and lymphadenectomy. The postoperative pathology and follow-up results were used to evaluate the efficacy. Results: Nine cases showed severe response to radiotherapy in postoperative cervical pathological tissues without residual tumor, and survived for more than 3-14 years, the median survival time was 8 years. All of 4 cases with residual tumor died within 1 year. Delayed healing of vaginal wounds occurred in 3 of the 12 cases. Conclusions: Cf-252 is a good brachytherapy source. The cervical tissue shows severe response to radiotherapy and prolonged healing time of vaginal wound is observed in some cases after CF-252 radiotherapy. To those uterine tumor patients with local suspicious lesions or poor prognostic factors after CF-252 neutron intracavity and external radiotherapy, extrafascial hysterectomy is a safe and feasible treatment method.

[Elevated blood pressure in childhood or adolescence and early cardiovascular damage]

With the increase of overweight and obesity, elevated blood pressure (BP) in children and adolescents has been an important public health issue globally. Many studies have assessed the association between elevated BP and early cardiovascular damage in children and adolescents. A majority of these studies have highlighted the effects of elevated BP on cardiovascular damage, but with partly inconsistent findings. The studies of biological mechanisms played important roles in illuminating the potential mechanisms of cardiovascular damage caused by elevated BP. In addition, studies on the interventions, including losing weight and lowing BP were beneficial to reduce the occurrence of or reverse early cardiovascular damage. In this review, we reviewed articles on the association between elevated BP and early cardiovascular damage (including structural and functional damage of cardiac and vessels) in children and adolescents, underlying biological mechanisms, and the effectiveness of interventions to provide a reference for the prevention and intervention of early cardiovascular damage caused by elevated BP in children and adolescents and then reduce the occurrence of cardiovascular disease in adulthood.

[Design of huantai childhood cardiovascular health cohort study]

Cardiovascular disease (CVD) has been an important public health issue in China. Recently, the prevalence of obesity, elevated blood pressure, hyperglycemia, dyslipidemia, and unhealthy lifestyles was high in Chinese children and adolescents, which might increase the risk of short-term target organ damage and adult CVD. Therefore, we selected one primary school in Huantai County, Zibo City between November 2017 and January 2018 to establish the Huantai Childhood Cardiovascular Health Cohort Study. The aim of this project was to investigate the effects of childhood exposures on short-term target organ damage and adult CVD, and to provide evidence to curb the epidemic of CVD in China from the source. A total of 1 515 children aged 6-11 years old were included at the baseline. In this paper, we will introduce the overall design of the survey, including participants, methods, quality control, basic characteristics of the participants, study limitations, and future directions, which might provide some useful implications for similar researches in the future.

[Estimating Postmortem Interval by Protein Chip Detection Technology Combined with Multidimensional Statistics]

Abstract

Objective To obtain the protein expression profile of rat liver tissue after death by the 2100 bioanalyzer combined with protein chip, and infer the relationship between protein expression profile and postmortem interval. Methods Rats were killed by abdominal anesthesia and placed at 16 ℃. Water-soluble proteins in liver tissues were extracted at 14 time points after death. The expression profile data of proteins with relative molecular weight of 14 000-230 000 were obtained using protein chip, and principal component analysis （PCA）, partial least squares-discriminant analysis （PLS-DA） and Fisher discriminant were used to analyze the data. Results According to the changes of protein expression profile, the postmortem interval was divided into group A （0 d）, group B （1-9 d）, group C （12-30 d） according to the result of PLS-DA. The prediction accuracy of the training set and test set of the model were all 100.0%, and the internal cross-validation of the training set was 100.0% according to Fisher discriminant. The Fisher discriminant model at each time point of group B and C was established to narrow the time window of postmortem interval estimation. The prediction accuracy of the training set and test set were all 100.0%, and the internal cross-validation accuracy of the training set was 100.0% in group B. The prediction accuracy of the training set and test set were respectively 95.2% and 78.6% in group C, and the internal cross-validation of the training set was 88.1%. Conclusion Protein chip detection technology can quickly and easily obtain the expression profile of water-soluble proteins of rat liver tissue with a relative molecular weight of 14 000-230 000 at different time points after death. PLS-DA and Fisher discriminant models are established to classify and predict the postmortem interval, in order to provide new ideas and methods for postmortem interval estimation.

[Association between elevated blood pressure and high carotid intima-media thickness in children according to different blood pressure references]

Objective: To analyze the association between elevated blood pressure (BP) and carotid intima-media thickness (cIMT) in children according to four BP references. Methods: Study population came from"Huantai Childhood Cardiovascular Health Cohort Study"in Huantai County, Zibo City, Shandong Province. A convenient cluster sampling method was used to conduct a cross-sectional survey on 1 515 children from November 2017 to January 2018 in a primary school. A total of 1 431 children aged 6-11 years old with complete data were included in this study. Data on demographic characteristics, BP and cIMT were collected through questionnaire survey, physical examination and ultrasound examination. High cIMT was defined as the level of cIMT ≥ age-and sex-specific 90^th percentile of this study population. Based on the Chinese Guideline reference, the Health Industry reference, the International reference and the U.S. reference, all participants were divided into three subgroups: the normal BP, high normal BP and, elevated BP. The multivariate logistic regression models were used to examine the association between BP status and high cIMT in children. Results: The age of children was (8.9±1.5) years, and boys accounted for 53.4% (n=682). The multivariate logistic regression models showed that after adjusting for relevant confounding factors, the risk of high cIMT in elevated BP group was increased compared with the normal BP group according to the four references (all P values<0.05) Conclusion: Elevated BP according to the four BP references is associated with high cIMT in children.

Expression of Autophagy-Associated Protein in Rat Muscle Tissues after Antemortem and Postmortem Injury

Abstract

Objective To study the expression of the three autophagy-associated proteins, BECN1, LC3 and p62, after the injury of the skeletal muscle of rats and to explore its application in differentiation between antemortem and postmortem injury. Methods The 72 healthy Sprague-Dawley rats were randomly divided into the undamaged control group, the antemortem injury group （0.5 h, 1 h, 2 h, 4 h, 8 h, 16 h and 24 h） and postmortem injury group （0.5 h, 1 h, 2 h and 4 h）. A model of the injured right hind limb of rats was constructed. The expressions of the autophagy-associated proteins, BECN1, LC3-2/LC3-1 and p62, in the control group, the antemortem injury group and postmortem injury group were detected by Western blotting method. The data were respectively centralized and standardized and the orthogonal partial least square-discrimination analysis （OPLS-DA） identification model of antemortem and postmortem injury groups was constructed. Results The expression of BECN1, p62 protein and LC3-2/LC3-1 after the injury of the skeletal muscle of the rats showed different degrees of changes, but the differences among the 3 groups had no statistical significance. Antemortem and postmortem injury groups can be distinguished by centralizing and standardizing the expression levels of autophagy protein BECN1 and the ratio of LC3-2/LC3-1. The principal components extracted from OPLS-DA model of antemortem injury and postmortem injury had a relatively good interpretation of the model （R_x²=0.563, R_y²=0.439）, but it were less predictive （Q²=0.366）. Conclusion The expression of BECN1 and the ratio of LC3-2/LC3-1 in injured local tissue of the rat skeletal muscle can be used for the differentiation of antemortem injury group and postmortem injury group.

[Establishment of Mathematical Models for Skeletal Age Determination of Extremitas Sternalis of Clavicle in Shanxi Adolescents]

Objective To develop mathematical models for skeletal age determination with multiple statistic method based on the correlation between age and the growth of the epiphysis of extremitas sternalis of clavicle in Shanxi adolescents. Methods The 562 Shanxi sternoclavicular joint samples （454 cases of modelling, 108 cases of external verification） were scanned by the thin-section computed tomography. After volume rendering was obtained, indicators such as area of epiphysis, area of metaphysis, longest diameter of epiphysis and longest diameter of metaphysis of both extremitas sternalis of clavicle were collected. Indicators such as the ratio of area of epiphysis to area of metaphysis, and the ratio of longest diameter of epiphysis to longest diameter of metaphysis of both sides were calculated. Then multiple linear regression and random forest discriminant models were used to build mathematical models for age determination of adolescents. Results The obtained indicators exhibited a strong correlation with age （r>0.85）. The multiple linear regression model for males and females （all 4 indicators entering the model） based on the ratio of longest diameter of epiphysis to longest diameter of metaphysis and the ratio of area of epiphysis to area of metaphysis had an internal validation accuracy rate （±1.0 year） of over 92% and 108 cases had an external validation accuracy rate of over 70% （±1.0 year）. The out of bag error rates of random forest discriminant models were less than 2% for people over 18.0 years old （≥18.0 years old） and under 18.0 years old. The external validation accuracy rates of the 108 cases were over 80%. Conclusion The regression and discriminant models established in this study have certain reliability and accuracy and can be used in age determination of Shanxi adolescents.

[Role of hepatic venous pressure gradient in the overall management process of portal hypertension]

Portal hypertension is a common complication of many chronic liver diseases and an important factor affecting the clinical prognosis of patients. Portal hypertension can bring a series of serious complications such as esophagogastric varices, gastrointestinal bleeding, ascites, spontaneous peritonitis, renal insufficiency, hypersplenism, and hepatopulmonary syndrome. Hepatic venous pressure gradient is the best clinical indicator that indirectly reflects the portal venous pressure. Currently, it is the gold standard test for diagnosing clinically significant portal hypertension. In addition, the hepatic venous pressure gradient has important application value in predicting the degree of liver cirrhosis, the risk and prognosis of portal hypertension variceal bleeding, ascites production, portal hypertension drugs reduction, and antiviral drugs efficacy. At the same time, individualized treatment based on portal pressure gradient has important theoretical and clinical significance, and provides new clinical ideas in the overall management of patients with portal hypertension.

[Analysis of influencing factors of shunt dysfunction after transjugular intrahepatic portosystemic shunt in liver cirrhosis accompanied with portal vein thrombosis]

Objective: To investigate the efficacy of shunt after transjugular intrahepatic portosystemic shunt (TIPS) in liver cirrhosis accompanied with portal vein thrombosis (PVT). Methods: Forty-four cases with liver cirrhosis accompanied with PVT who underwent TIPS treatment from January 2015 to May 2018 were retrospectively analyzed. Clinical baseline data of the patients were collected. Portal vein pressure gradient (PVPG) before and after the surgery was recorded. Shunt patency was observed at 3, 6, 12, 18 and 24 months after the surgery. The influencing factors were determined by univariate and multivariate analysis. Results: Transjugular intrahepatic portosystemic shunt was successfully established in all 44 cases. The postoperative PVPG was lower than preoperative (P < 0.01). The shunt patency rate after TIPS in PVT was 18.2% (n = 8). The cumulative shunt patency rates at 3, 6, 12, 18, and 24 months after surgery were 95.5%, 90.7%, 90.7%, 86.8% and 74.4%, respectively. Univariate analysis showed that diabetes history, platelet level and prothrombin time-international normalized ratio were associated with postoperative shunt dysfunction. Multivariate analysis showed that diabetes history (P = 0.007, OR = 28.606) was an independent risk factor for postoperative shunt dysfunction. Conclusion: TIPS is a safe and feasible procedure, which can effectively reduce the portal pressure in liver cirrhosis accompanied with PVT. Diabetic patients have a higher risk of postoperative shunt dysfunction. Therefore, clinical intervention should be strengthened for high-risk patients.

Determination of Escitalopram in Biological Samples by Dispersive Liquid-Liquid Microextraction Combined with GC-MS/MS

Objective To establish a method for determination of escitalopram in biological samples by ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with gas chromatography-tandem mass spectrometry （GC-MS/MS） and provide evidences for forensic determination of cases related to escitalopram. Methods The 1-hexyl-3-methylimidazolium hexafluorophosphate （[C₆MIM][PF₆]） was selected as an extract solvent to process biological samples. Ultrasound-assisted extraction was used on the samples. Then the samples were detected by GC-MS/MS. Results The linear range of escitalopram in blood and liver were 5.56-1 111.10 ng/mL and 0.025-5.00 mg/g, respectively. The correlation coefficient （r） were greater than 0.999, limit of detection （LOD） were 4.00 ng/mL and 2.00 μg/g, limit of quantitation （LOQ） were 14.00 ng/mL and 6.00 μg/g, respectively. The extraction recovery rates were all greater than 50%, the interday and intraday precision were less than 20%. Escitalopram was detected in blood and liver samples from the actual poisoning case by this method with a content of 1.26 μg/mL and 0.44 mg/g, respectively. Conclusion The ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with GC-MS/MS is environment friendly, rapid, has good enriching effect and consumes less organic solvent and can be used for forensic determination of escitalopram related cases.

[Excision for congenital nasal dermoid and sinus cyst in children]

Objective: To explore the surgical effect and experience of endoscope-assisted excision for congenital nasal dermoid and sinus cyst (NDSC) in children. Methods: Fifty-three patients with congenital NDSC treated in Beijing Children's Hospital from January 2007 to December 2018 were retrospectively reviewed, including 30 boys and 23 girls, with the age ranging from 9 to 145 months (mean age 35.6 months). The ultra-low-dose CT scan and MRI of the paranasal sinuses were performed for all patients. Excisions of NDSC under general anesthesia were performed for all patients, and surgical approaches were dependent on location and extent of the lesions according to radiographic workups. All intra-osseous patients and complicated superficial cases underwent surgical excision of NDSC and nasal reconstruction with the assistance of endoscope. Initial presentation, medical history, imaging workups, surgical approaches, complications, rates of recurrence and cosmetic outcomes were evaluated. Descriptive statistics was used for the results analysis. Results: Among 53 cases, the most common presentation included a nasal-glabella mass (n=21, 39.6%), a dorsal punctum (n=13, 24.5%) and a dorsal mass (n=9, 17.0%). The sites of NDSC included nasal glabella (n=22, 41.5%), nasal bridge (n=27, 50.9%) and nasal tip (n=4, 7.5%). Of all patients, 24 cases (45.3%) had superficial lesions, 19 cases (35.8%) had intraosseous extension into the frontonasal bones, 10 cases (18.9%) extended intracranially but remained extradural. Surgical approaches included transverse incision (n=22, 41.5%), minimal midline vertical incision (n=27, 50.9%) and external rhinoplasty (n=4, 7.5%). All NDSC were successfully excised and no nasal reconstruction needed. All cases were followed up from 9 to 151 months with a mean of 67.3 months. Five patients (9.4%) with recurrence were observed and were managed successfully with reoperation. During the follow-up, no nasal deformity was noted, and cosmetic outcome was favorable for all patients. Conclusion: Endoscope-assisted excision has the advantage of clear vision, small trama and low recurrence rate for children with NDSC.

[Clinical value of early bedside ultrasound measurement of quadriceps femoris in diagnosis of ICU-acquired weakness]

Objective: To explore the correlation between quadriceps thickness (thickness of rectus femoris and vastus intermedius), cross-sectional area (cross-sectional area of the rectus femoris) and the strength score of the Medical Research Council (MRC) in critically ill patients, and to explore the changes in the length of hospital stay in the intensive care unit (ICU), and to determine the diagnostic value of muscle changes in the ICU-acquired weakness (ICU-AW). Methods: Patients admitted to the Department of Critical Care Medicine from March to October in 2019 who were expected to stay for more than five days were enrolled in this study. The cross-sectional area of the rectus femoris, the thickness of the rectus femoris, the thickness of the vastus intermedius on the first day of the ICU (D(1)), day 3 (D(3)), and day 5 (D(5)), day 7 (D(7)), out of ICU (D(ICU)), and the MRC muscle strength scores on the day of out of ICU prospectively were collected in all the patients, and the correlation and the regularity of quadriceps changes were analyzed. MRC>48 points on the day of dismiss of ICU were used as the standard for the diagnosis of ICU-AW, and the relationship between muscle changes of the quadriceps and ICU-AW was analyzed. The t test or the Mann-Whitney U test was used for data analysis. Results: A total of 45 patients were included, including 25 males and 20 females, aged (58±10) years. The rectus femoris cross-sectional area, rectus femoris thickness, and vastus intermedius thickness decreased with the length of ICU hospital stay. The cross-sectional area, thickness of the rectus femoris muscle, and the vastus intermedius thickness were positively correlated with the MRC score (r=0.452, 0.411, 0.402, all P<0.05), and the changes were all negatively correlated with the MRC score (r=-0.682, -0.740, -0.734, all P<0.05). On the 3rd day after ICU admission, the best cutoff value of rectus muscle cross-sectional area atrophy rate for discrimination of ICU-AW was 6.0%, with a sensitivity of 66.7% and a specificity of 77.8%; on the 5th day, the best cutoff value of rectus femoris thickness atrophy rate was 14.5%, with a sensitivity of 77.8% and a specificity of 66.7%; on the 7th day, the best cutoff value of vastus intermedius thickness atrophy rate was 19.9%, with a sensitivity of 70.6% and a specificity of 87.5%. Conclusion: Bedside ultrasound measurement of the quadriceps femoris cross-sectional area and thickness has certain diagnostic value for ICU-AW, and can identify patients with ICU-AW early.

[Neonatal capillary malformation-arteriovenous malformation complicated with acute heart failure: a case report and literature review]

Objective: To study the clinical characteristics and current treatment of neonatal capillary malformation-arteriovenous malformation (CM-AVM). Methods: Clinical data of a newborn diagnosed with neonatal CM-AVM caused by RASA1 gene variation admitted to Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine was retrospectively analyzed, and related literature was reviewed. Databases of CNKI, WanFang, and Pubmed were searched for the literature from January 1, 2009 to December 31, 2018, with the keywords of "capillary malformation-arteriovenous malformation" "neonatal" and "RASA1 gene" . The clinical features of neonatal CM-AVM were summarized. Results: A one-day-old male infant was admitted to hospital due to swelling of both lower extremities with erythema with elevated skin temperature, who later presented with acute heart failure on the third day of hospitalization. A giant spinal arteriovenous fistula was identified by abdominal contrast-enhanced computed tomography and digital subtraction angiography. After surgical ligation of two feeding arteries, both heart failure and lower limb swelling improved. Genetic testing detected a novel paternal heterozygous variation of RASA1 gene. Digital subtraction angiography showed that spinal AVM still exist at the age of 6 months, but the heart function was good. A total of 4 cases of neonatal CM-AVM had been reported in 3 papers. According to these 5 cases, the clinical manifestations of neonatal CM-AVM were summarized: multiple dermal capillary malformation (5 cases), limb swelling or head circumference enlargement (5 cases), arteriovenous malformation (5 cases), congestive heart failure (4 cases) and positive family history (5 cases). Conclusions: CM-AVM is a rare disease and could present early in neonatal period. Capillary malformation and congestive heart failure of unknown origin in infants may indicate the existence of CM-AVM, and timely imaging and genetic test will help early diagnosis and treatment, and improve prognosis.

[A Qualitative Proteome-Wide Lysine Succinylation Profiling of Tea Revealed its Involvement in Primary Metabolism]

Lysine succinylation of proteins has potential impacts on protein structure and function, which occurs on post-translation level. However, the information about the succinylation of proteins in tea plants is limited. In the present study, the significant signal of succinylation in tea plants was found by western blot. Subsequently, we performed a qualitative analysis to globally identify the lysine succinylation of proteins using high accuracy nano LC-MS/MS combined with affinity purification. As a result, a total of 142 lysine succinylation sites were identified on 86 proteins in tea leaves. The identified succinylated proteins were involved in various biological processes and a large proportion of the succinylation sites were presented on proteins in the primary metabolism, including glyoxylate and dicarboxylate metabolism, TCA cycle and glycine, serine and threonine metabolism. Moreover, 10 new succinylation sites were detected on histones in tea leaves. The results suggest that succinylated proteins in tea plants might play critical regulatory roles in biological processes, especially in the primary metabolism. This study not only comprehensively analyzed the lysine succinylome in tea plants, but also provided valuable information for further investigating the functions of lysine succinylation in tea plants.

Increasing frequency and severity of odontogenic infection requiring hospital admission and surgical management

Odontogenic infections can become life-threatening if not managed in a timely manner, and they increase the physical cost of treatment to the patient and the financial cost to the public health system. We investigated the number of admissions to a Queensland tertiary hospital within a decade, and differences in the patients' characteristics, severity at presentation, and clinical outcomes. We compared patients with odontogenic infections who were taken to theatre at the Royal Brisbane & Women's Hospital (RBWH) between January 2003 and December 2004 with those treated between January 2013 and December 2014, a total of 292. Data on demographics, presentation, previous history, antimicrobial treatment, and admissions, were collated and analysed. There were no significant differences in demographics. In the 2013/2014 group there was a two-fold increase in infections related to lower third molars (p=0.001), a 50% increase in trismus (p=0.001), and a 20% increase in submandibular swelling (p=0.010). The percentage of patients admitted to the intensive care unit (ICU) was three and a half times higher in the 2013/2014 group (p=0.001). The presentation of odontogenic infections has increased in the decade from 2003/2004 to 2013/2014. Measures of the severity of disease have increased, while the basic characteristics of the patients have remained constant. Improved primary preventative measures and early interventions are therefore needed to alleviate the burden that these infections place on the public health system.

Wound Age Estimation by Neutrophil Migration Distance

Abstract

Objective To explore the application of neutrophil migration distance for wound age estimation of skeletal muscles in rats, and to provide methodological basis for follow-up study in future. Methods The skeletal muscle contusion model was established in rats, and the control group and the 2, 4, 6 h post-traumatic groups were set. The law of response of neutrophils that participated in the inflammation after injury was detected by immunohistochemical staining, and the relationship between neutrophil migration distance and injury time was detected by TissueFAXS PLUS software. Results The skeletal muscle was obviously infiltrated with neutrophils 2-6 h after injury. The positive rate of neutrophil was （28.75±0.94）% at 2 h post-traumatic, and reached the peak （45.50±3.63）% at 4 h post-traumatic, then decreased to （31.92±1.56）% at 6 h post-traumatic. The neutrophil migration distances increased with the progress of inflammation, and reached （124.80±12.32） μm, （229.03±21.45） μm and （335.04±16.75） μm at 2 h, 4 h and 6 h, respectively. Conclusion There is a relationship of neutrophil infiltrated number and migration distance and wound age within the 2-6 h after skeletal muscle injury, which could be used for the inference of skeletal muscle wound age.

Enhanced visible light absorption performance of SnS2 and SnSe2 via surface charge transfer doping

The layered two-dimensional (2D) SnS₂ and SnSe₂ have received intensive attention due to their sizable band gaps and potential properties. However, it has been shown that the visible light absorption of SnS₂ and SnSe₂ are restricted as photocatalysts and light-harvesting material absorbers for water splitting and high-performance optoelectronic devices. Herein, to enhance the visible light absorption performance of SnS₂ and SnSe₂, we performed a systematic investigation on tuning the electronic and optical properties of monolayers SnS₂ and SnSe₂ via surface charge transfer doping (SCTD) with the adsorption of molybdenum trioxide (MoO₃) and potassium (K) as surface dopants based on density functional theory. Our calculations reveal that MoO₃ molecules and K atoms can draw/donate electrons from/to SnS₂ and SnSe₂ as acceptors and donors, respectively. The adsorption of MoO₃ molecules introduces a new flat impurity state in the gap of the monolayers SnS₂/SnSe₂, and the Fermi level moves correspondingly to the top of valence band, resulting in a p-type doping of the monolayer SnS₂/SnSe₂. With the adsorption of K atoms, the electrons can transfer from K atoms to the monolayer of SnS₂ and SnSe₂, making K an effective electron-donating dopant. Meanwhile, the bandgaps of monolayers SnS₂ and SnSe₂ decrease after the MoO₃ and K doping, which leads to the appearance of appreciable new absorption peaks at around ∼650/480 and ∼600/680 nm, respectively, and yielding an enhanced visible light absorption of SnS₂ and SnSe₂. Our results unveil that SCTD is an effective way to improve the photocatalytic and light-harvesting performance of SnS₂ and SnSe₂, broadening their applications in splitting water and degrading environmental pollutants under sunlight irradiation.

Homogeneity of Different Functional mRNA Indicators for Wound Age Estimation

OBJECTIVES

To explore the homogeneity level of four different functional mRNA （PUM2, TAB2, Cx45 and CHRNA1） expressions in rats with skeletal muscle contusion.

METHODS

The relative expressions of PUM2, TAB2, Cx45 and CHRNA1 mRNAs were detected by quantitative real-time reverse transcription-polymerase chain reaction （RT-qPCR）. The coefficient of variation （CV） of the relative expressions for different individuals in each injury group was calculated. The extreme value of CV, cumulative variability, and CV_CV were compared.

RESULTS

A high CV of PUM2 and TAB2 mRNAs appeared on several different time points. However, the CV of Cx45 and CHRNA1 mRNAs was relatively low. The cumulative variability from high to low was PUM2, CHRNA1, TAB2 and Cx45 mRNAs. The relative expression of PUM2 mRNA was significantly higher than that of TAB2, Cx45 and CHRNA1 mRNAs （ P<0.05）. There was no statistical significance （P>0.05） in the CV_CV of the relative expression of TAB2, CHRNA1 and Cx45 mRNAs.

CONCLUSIONS

As the mRNAs involving in biological process regulation, PUM2 and CHRNA1 mRNAs show a lowest individual homogeneity of the relative expression followed by TAB2 mRNA. As the mRNAs participating in the composition of cellular structure, Cx45 and CHRNA1 mRNAs show a high individual homogeneity of the relative expressions. The functional classification should be considered for the screening of the mRNA indicators used for wound age estimation.

Disease-Associated Short Tandem Repeats Co-localize with Chromatin Domain Boundaries

More than 25 inherited human disorders are caused by the unstable expansion of repetitive DNA sequences termed short tandem repeats (STRs). A fundamental unresolved question is why some STRs are susceptible to pathologic expansion, whereas thousands of repeat tracts across the human genome are relatively stable. Here, we discover that nearly all disease-associated STRs (daSTRs) are located at boundaries demarcating 3D chromatin domains. We identify a subset of boundaries with markedly higher CpG island density compared to the rest of the genome. daSTRs specifically localize to ultra-high-density CpG island boundaries, suggesting they might be hotspots for epigenetic misregulation or topological disruption linked to STR expansion. Fragile X syndrome patients exhibit severe boundary disruption in a manner that correlates with local loss of CTCF occupancy and the degree of FMR1 silencing. Our data uncover higher-order chromatin architecture as a new dimension in understanding repeat expansion disorders.

[Study on Urinary Metabolic Profile in Rats with Deep Venous Thrombosis Based on Pattern Recognition]

OBJECTIVES

To study the urinary metabolic profile in rats with deep venous thrombosis （DVT） based on metabolomics and to screen out small molecular biomarkers for the diagnosis and forensic identification of DVT.

METHODS

Inferior vena cava of rats was ligated to construct DVT models. The rats were randomly divided into three groups： DVT, sham, and control groups, 10 in each group. The urine of DVT and sham rats was collected during 24 hours in the metabolic cage at 48 hours after operating, meanwhile, 24 hours urine was collected in control group. The metabolic profile was analyzed by nuclear magnetic resonance. SIMCA-P 14.1 software was used for pattern recognition. The variable importance in projection （VIP） value from orthogonal PLS-DA （OPLS-DA） model combined with Mann-Whitney U test were used to search the different metabolites in the urine.

RESULTS

The metabolic profiles of urine from DVT, sham, and control groups had significant differences. The DVT, sham, and control groups could be distinguished by the partial least squares method-discriminant analysis （PLS-DA） model. Compared with the urine of the rats in control groups, the levels of leucine, glutamine, creatine, creatinine and sucrose in the urine of DVT rats were up-regulated, and the levels of 3-hydroxybutyrate, lactate, acetone, α-oxoglutarate, citrate and hippurate were down-regulated.

CONCLUSIONS

The different metabolites in the urine of DVT rats are expected to become its candidate biomarkers. The results can provide a research basis for the diagnosis, treatment and forensic identification of DVT.

[Effects of Temperature on FTIR Spectral Characteristics of Renal Tissue in Rats after Death]

OBJECTIVES

To analyse the Fourier transform infrared （FTIR） spectral data of renal tissue at different temperatures in rats after death, and to explore the effects of temperature on the FTIR spectral characteristics of renal tissue.

METHODS

The rats were sacrificed by cervical dislocation and placed at 4 ℃, 20 ℃ and 30 ℃. The FTIR spectral data of renal tissue were collected at different time points and analysed by data mining method.

RESULTS

The principal component analysis （PCA） results showed that there were significant trends of clustering in the samples of partial time point at 4 ℃, 20 ℃ and 30 ℃. Partial least square （PLS） regression models were established with the spectral data at three temperature groups. The performance of PLS regression models in 20 ℃ and 30 ℃ groups were more superior than that in 4 ℃ group, and the stability of the model in 20 ℃ group was better than that in 30 ℃ group.

CONCLUSIONS

There are differences in the FTIR spectral characteristics of renal tissue of rats after death at different temperatures. Temperature has a major impact on the performance of FTIR spectral PLS regression model. Therefore, in order to improve the accuracy of postmortem interval estimation, the effects of temperature on the model should be considered in the related study by spectral method.

[Establishment of the Mathematical Model for PMI Estimation Using FTIR Spectroscopy and Data Mining Method]

OBJECTIVES

To analyse the relationship between Fourier transform infrared （FTIR） spectrum of rat's spleen tissue and postmortem interval （PMI） for PMI estimation using FTIR spectroscopy combined with data mining method.

METHODS

Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method.

RESULTS

The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis （PCA） showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis （PLS-DA） and support vector machine classification （SVMC） effectively divided the spectrum samples with different PMI into four categories （0-24 h, 48-72 h, 96-120 h and 144-168 h）. The determination coefficient （R²） of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration （RMSEC） and root mean square error of cross validation （RMSECV） were 9.90 h and 11.39 h respectively. In prediction set, the R² was 0.97, and the root mean square error of prediction （RMSEP） was 10.49 h.

CONCLUSIONS

The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation.

[Time-dependent Expression of Nrf2 Protein and its Effects on Wound Repair in Skeletal Muscle]

OBJECTIVES

To detect the expression of nuclear factor erythroid 2-related factor 2 （Nrf2） to explore its change rule and effects in the repair process of skeletal muscle.

METHODS

An injury model of skeletal muscle was established by injection of cardiotoxin into the gastrocnemius muscle of SD male rats. The muscle samples were taken from control group and injury group at each time point （1 h, 4 h, 8 h, 12 h, 16 h, 1 d, 3 d, 5 d, 7 d, 9 d, 13 d, 17 d, 21 d）. The morphological changes of skeletal muscle in repair process were observed by HE staining, and the content of reactive oxygen species （ROS） was detected. The expression level of Nrf2 protein was investigated by Western blotting and immunohistochemistry staining.

RESULTS

After the skeletal muscle injury, the injury region was infiltrated with inflammatory cells which constituted mainly by lymphocyte neutrophils and mononuclear cells. There were large amounts of immature muscle cells appeared at the 5th day and the muscle repair was completed at the 21th day. Comparing with control group, the ROS content decreased in injury group at the 12th hour （P<0.05）, while Nrf2 expression increased at the 16th hour （P<0.05）. Moreover, the positive rate of Nrf2 increased after injury, and peaked at 16 h-1 d, then decreased gradually and returned to the level of control group （P<0.05）.

CONCLUSIONS

The Nrf2 protein involves in the regulation of the repair of skeletal muscle injury. The positive rate of Nrf2 shows a time-dependent expression, which can be used to estimate the wound age of skeletal muscle.

[Investigation of doctors' and nurses' perceptions and implementation of delirium management in intensive care unit]

Objective: To investigate doctors' and nurses' perceptions and implementation of delirium management in intensive care unit. Methods: A total of 197 doctors and nurses in 2 general ICUs and 3 special ICUs at Peking Union Medical College Hospital finished a self-designed questionnaire of delirium management. Results: There were 47 males and 150 females, 43 doctors and 154 nurses who participated in the survey.One hundred and twenty five participators were from general ICU and the others from special ICU. The ICU staff had a significant difference on the perceptions and implementation of delirium management(P< 0.001) including. Doctors and nurses scored lowest in "family engagement and empowerment" and "sleep management" with (4.620±2.393) and (5.430±2.153) respectively. There was a significant difference between nurses and doctors in the management of analgesia and sedation (P< 0.05).Doctors and nurses from different ICUs had significant discrepancy in the implementation of "delirium assessment" (P< 0.05). Conclusions: The ICU staff should improve the perceptions and the implementation of delirium management,especially in special ICUs. Delirium management should be included as a routine care in ICU to improve patients' outcome.

Time-dependent Expression of MT1A mRNA and MT2A mRNA in the Contused Skeletal Muscle of Rats

OBJECTIVES

To investigate the time-dependent expression of metallothionein （MT） 1A mRNA and MT2A mRNA in contused skeletal muscle of rats.

METHODS

A total of 54 Sprague-Dawley rats were used in this study. The rats were divided into two parts: control group （n=6） and contusion groups （0.5, 1, 6, 12, 18, 24, 30, and 36 h after contusion, n=6）. Total RNA was extracted from skeletal muscle. The expression levels of MT1A mRNA and MT2A mRNA were detected by SYBR Green I real-time PCR.

RESULTS

The expression trends of the two potential marker genes were related to wound age. In addition to 0.5 h, there were significant contrasts between the control group and contused group （P<0.05）, about the expression levels of MT1A mRNA and MT2A mRNA in different phases. As the extension of wound age, the relative expression of MT1A mRNA and MT2A mRNA at 1 h, 6 h, 12 h and 18 h after contusion demonstrated upgrade tendency until its expression levels in 18 h peak with 239.41±15.20 and 717.42±50.76, respectively. When time extends to 24 h after injury, the expression of above two marks decreased, respectively. The MT1A mRNA and MT2A mRNA expression levels increased at 30 h and then decreased.

CONCLUSIONS

Determination of MT1A mRNA and MT2A mRNA levels by real-time PCR may be useful for the estimation of wound age.

[Relationship between Wound Age and the Expression of Fzd2 in Rats Skeletal Muscle after Contusion]

OBJECTIVES

To investigate the relationship between wound age and the expressions of frizzled-2 （Fzd2） mRNA and its protein in rats skeletal muscle after contusion, and to explore its possibility of being an index for wound age estimation.

METHODS

The mRNA and protein expressions of Fzd2 in rats skeletal muscle of the control group and the experimental group within 4-48 h after contusion were detected per 4 h by RT-qPCR and Western blotting.

RESULTS

AThe relative expression of Fzd2 mRNA increased at 24 h, 36 h and 40 h after contusion, and the expression at 24 h was twice as the control group （ P<0.05）. The relative expression of Fzd2 protein changed inconspicuously after contusion （P>0.05）.

CONCLUSIONS

The changes of Fzd2 mRNA expression after contusion in a certain time can be a basis to estimate wound age by combined multi-indicators.

[New challenges to the treatment of cervical intraepithelial neoplasia]

Due to the progress of intracavitary afterloading technology and dosage of brachytherapy, a similar dose distribution as that of cervical conization can be achieved and can be applied to the treatment of cervical intraepithelial neoplasia (CIN), it is called "afterloading conization" . Being adjusted the radioactive source movement and weight, low exposure doses to the ovary, endometrium and vagina can be assured. So a high quality of life after treatment could be maintained and overcomes the shortcomings of cervical conization and hysterectomy, such as anesthesia, bleeding, over or insufficient treatment, early ovarian ageing and operative complications.

Identification of polymorphisms and transcriptional activity of the proto-oncogene KIT located on both autosomal and B chromosomes of the Chinese raccoon dog

B chromosomes are dispensable and co-exist with autosomal and sex chromosomes. The karyotype of the Chinese raccoon dog (Nyctereutes procyonoides procyonoides) comprises 0-4 B chromosomes. The proto-oncogene KIT is found on all B chromosomes of the Chinese raccoon dog. In the present study, partial DNA and mRNA sequences of KIT were amplified and sequenced from four individuals containing B chromosomes. Sequence analyses revealed that polymorphisms including single nucleotide polymorphisms (SNPs) and inserts/deletions were rich in the KIT gene of Chinese raccoon dog at the genomic level. However, no polymorphism was detected at the mRNA level. A comparison of mRNA sequences from Chinese raccoon dogs with the corresponding sequences derived from arctic fox and dog, which do not contain B chromosomes, revealed the mRNA sequences of the 10 SNPs to be identical between these three species. Therefore, these findings suggest that KIT located on the B chromosomes in Chinese raccoon dog lacks transcriptional activity.

Identification of cDNA sequences and alternative splicing patterns of canine AMEL genes (AMELX and AMELY)

Amelogenin is a major protein of the developing enamel matrix. There are two amelogenin genes (AMELX and AMELY) located on the X and Y chromosomes, respectively, in dogs. In the present study, we characterized full-length cDNAs and alternative splicing patterns of the AMEL genes in the tooth tissue of a dog by 5'- and 3'-rapid amplification of cDNA ends and AMEL-specific RT-PCR. Sequence analysis revealed that the coding regions of AMELX and AMELY were 579 and 576 bp (accession Nos. KP244310 and KP244311), respectively. The coding sequence of AMELX had 95.1% identity to that of AMELY. The AMEL genes on X and Y chromosomes were both expressed in developing tooth tissue. Eight different alternatively spliced transcripts were identified, five from AMELX and three from AMELY.

Runoff characteristics and non-point source pollution analysis in the Taihu Lake Basin: a case study of the town of Xueyan, China

Non-point source pollution is a significant environmental issue in small watersheds in China. To study the effects of rainfall on pollutants transported by runoff, rainfall was monitored in Xueyan town in the Taihu Lake Basin (TLB) for over 12 consecutive months. The concentrations of different forms of nitrogen (N) and phosphorus (P), and chemical oxygen demand, were monitored in runoff and river water across different land use types. The results indicated that pollutant loads were highly variable. Most N losses due to runoff were found around industrial areas (printing factories), while residential areas exhibited the lowest nitrogen losses through runoff. Nitrate nitrogen (NO3-N) and ammonia nitrogen (NH4-N) were the dominant forms of soluble N around printing factories and hotels, respectively. The levels of N in river water were stable prior to the generation of runoff from a rainfall event, after which they were positively correlated to rainfall intensity. In addition, three sites with different areas were selected for a case study to analyze trends in pollutant levels during two rainfall events, using the AnnAGNPS model. The modeled results generally agreed with the observed data, which suggests that AnnAGNPS can be used successfully for modeling runoff nutrient loading in this region. The conclusions of this study provide important information on controlling non-point source pollution in TLB.

Diadenylate cyclase evaluation of ssDacA (SSU98_1483) in Streptococcus suis serotype 2

Cyclic diadenosine monophosphate is a recently identified signaling molecule. It has been shown to play important roles in bacterial pathogenesis. SSU98_1483 (ssDacA), which is an ortholog of Listeria monocytogenes DacA, is a putative diadenylate cyclase in Streptococcus suis serotype 2. In this study, we determined the enzymatic activity of ssDacA in vitro using high-performance liquid chromatography and mass spectrometry. Our results showed that ssDacA was a diadenylate cyclase that converts ATP into cyclic diadenosine monophosphate in vitro. The diadenylate cyclase activity of ssDacA was dependent on divalent metal ions such as Mg(2+), Mn(2+), or Co(2+), and it is more active under basic pH than under acidic pH. The conserved RHR motif in ssDacA was essential for its enzymatic activity, and mutation in this motif abolished the diadenylate cyclase activity of ssDacA. These results indicate that ssDacA is a diadenylate cyclase, which synthesizes cyclic diadenosine monophosphate in Streptococcus suis serotype 2.

Cloning and association analysis of KIT and EDNRB polymorphisms with dominant white coat color in the Chinese raccoon dog (Nyctereutes procyonoides procyonoides)

The Chinese raccoon dog (Nyctereutes procyonoides procyonoides) is one of the most important fur-bearing animal species. The dominant white individual, a coat color variant in farmed Chinese raccoon dog, shows a completely white phenotype over the entire body. The KIT and EDNRB genes have been reported to be associated with the dominant white coat color in some mammalian species. In the present study, the full-length coding sequences of KIT and EDNRB were amplified from a dominant white and a wild-type Chinese raccoon dog. Sequence analysis revealed that the coding region of KIT and EDNRB in Chinese raccoon dog was 2919 and 1332 base pairs in length (accession No. KM083121 and KM083122), respectively, and 2 single-nucleotide polymorphisms (SNPs; c.600C>T and c.967G>A) in KIT and 1 SNP (c.259A>C) in EDNRB was found only in the dominant white individual. An alternative splicing site at the boundary of 4 and 5 of the KIT gene was identified in both individuals. We further investigated the association between the 3 SNPs of KIT and EDNRB and dominant white coat color by genotyping 18 individuals. We found no association between these SNPs and dominant white coat color. Based on these results, we can exclude the coding regions of the KIT and EDNRB genes as determinants of the dominant white coat color in Chinese raccoon dog.

An electrochemical surface plasmon resonance imaging system targeting cell analysis

This paper presents an electrochemical-surface plasmon resonance imaging (EC-SPRI) system, enabling the characterization of optical and electrical properties of cells, simultaneously. The developed surface plasmon resonance (SPR) imaging system was capable of imaging micro cavities with a dimension of 10 μm × 10 μm and differentiated glycerol solutions with a group of refractive indices (RIs). Furthermore, the EC-SPRI system was used to image A549 cells, suggesting corresponding RI and morphology changes during the cell death process. In the end, electrochemical and SPR methods were used in combination, recording oxidation peaks of A549 cells in the cyclic voltage curves and SPR response unit increase, simultaneously.