Pathological Characteristics and Classification of Unstable Coronary Atherosclerotic Plaques

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart disease, such as acute or chronic myocardial ischemic changes, sometimes make it difficult to locate the ischemic site due to the short death process, the lack of tissue reaction time. In some cases, the deceased died of sudden death on the first-episode, resulting in difficulty for medical examiners to make an accurate diagnosis. However, clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process. This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medical research, including plaque rupture, plaque erosion and calcified nodules, as well as the influencing factors leading to plaque instability, and briefly describes the research progress and technique of the atherosclerotic plaques, in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different pathologic states of coronary atherosclerotic plaques.

Multi-omics integration strategy in the post-mortem interval of forensic science

Estimates of post-mortem interval (PMI), which often serve as pivotal evidence in forensic contexts, are fundamentally based on assessments of variability among diverse molecular markers (including proteins and metabolites), their correlations, and their temporal changes in post-mortem organisms. Nevertheless, the present approach to estimating the PMI is not comprehensive and exhibits poor performance. We developed an innovative approach that integrates multi-omics and artificial intelligence, using multimolecular, multimarker, and multidimensional information to accurately describe the intricate biological processes that occur after death, ultimately enabling inference of the PMI. Called the multi-omics stacking model (MOSM), it combines metabolomics, protein microarray electrophoresis, and fourier transform-infrared spectroscopy data. It shows improved prediction accuracy of the PMI, which is urgently needed in the forensic field. It achieved an accuracy of 0.93, generalized area under the receiver operating characteristic curve of 0.98, and minimum mean absolute error of 0.07. The MOSM integration framework not only considers multiple markers but also incorporates machine-learning models with distinct algorithmic principles. The diversity of biological mechanisms and algorithmic models further ensures the generalizability and robustness of PMI estimation.

Novel ratio-expressions of genes enables estimation of wound age in contused skeletal muscle

Given that combination with multiple biomarkers may well raise the predictive value of wound age, it appears critically essential to identify new features under the limited cost. For this purpose, the present study explored whether the gene expression ratios provide unique time information as an additional indicator for wound age estimation not requiring the detection of new biomarkers and allowing full use of the available data. The expression levels of four wound-healing genes (Arid5a, Ier3, Stom, and Lcp1) were detected by real-time polymerase chain reaction, and a total of six expression ratios were calculated among these four genes. The results showed that the expression levels of four genes and six ratios of expression changed time-dependent during wound repair. The six expression ratios provided additional temporal information, distinct from the four genes analyzed separately by principal component analysis. The overall performance metrics for cross-validation and external validation of four typical prediction models were improved when six ratios of expression were added as additional input variables. Overall, expression ratios among genes provide temporal information and have excellent potential as predictive markers for wound age estimation. Combining the expression levels of genes with ratio-expression of genes may allow for more accurate estimates of the time of injury.

[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.

Exploring postmortem succession of rat intestinal microbiome for PMI based on machine learning algorithms and potential use for humans

The microbial communities may undergo a meaningful successional change during the progress of decay and decomposition that could aid in determining the post-mortem interval (PMI). However, there are still challenges to applying microbiome-based evidence in law enforcement practice. In this study, we attempted to investigate the principles governing microbial community succession during decomposition of rat and human corpse, and explore their potential use for PMI of human cadavers. A controlled experiment was conducted to characterize temporal changes in microbial communities associated with rat corpses as they decomposed for 30 days. Obvious differences of microbial community structures were observed among different stages of decomposition, especially between decomposition of 0-7d and 9-30d. Thus, a two-layer model for PMI prediction was developed based on the succession of bacteria by combining classification and regression models using machine learning algorithms. Our results achieved 90.48% accuracy for discriminating groups of PMI 0-7d and 9-30d, and yielded a mean absolute error of 0.580d within 7d decomposition and 3.165d within 9-30d decomposition. Furthermore, samples from human cadavers were collected to gain the common succession of microbial community between rats and humans. Based on the 44 shared genera of rats and humans, a two-layer model of PMI was rebuilt to be applied for PMI prediction of human cadavers. Accurate estimates indicated a reproducible succession of gut microbes across rats and humans. Together these results suggest that microbial succession was predictable and can be developed into a forensic tool for estimating PMI.

[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.

Postmortem Interval Estimation Using Protein Chip Technology Combined with Multivariate Analysis Methods

OBJECTIVES

To estimate postmortem interval (PMI) by analyzing the protein changes in skeletal muscle tissues with the protein chip technology combined with multivariate analysis methods.

METHODS

Rats were sacrificed for cervical dislocation and placed at 16 ℃. Water-soluble proteins in skeletal muscles were extracted at 10 time points (0 d, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, 7 d, 8 d and 9 d) after death. Protein expression profile data with relative molecular mass of 14 000-230 000 were obtained. Principal component analysis (PCA) and orthogonal partial least squares (OPLS) were used for data analysis. Fisher discriminant model and back propagation (BP) neural network model were constructed to classify and preliminarily estimate the PMI. In addition, the protein expression profiles data of human skeletal muscles at different time points after death were collected, and the relationship between them and PMI was analyzed by heat map and cluster analysis.

RESULTS

The protein peak of rat skeletal muscle changed with PMI. The result of PCA combined with OPLS discriminant analysis showed statistical significance in groups with different time points (P<0.05) except 6 d, 7 d and 8 d after death. By Fisher discriminant analysis, the accuracy of internal cross-validation was 71.4% and the accuracy of external validation was 66.7%. The BP neural network model classification and preliminary estimation results showed the accuracy of internal cross-validation was 98.2%, and the accuracy of external validation was 95.8%. There was a significant difference in protein expression between 4 d and 25 h after death by the cluster analysis of the human skeletal muscle samples.

CONCLUSIONS

The protein chip technology can quickly, accurately and repeatedly obtain water-soluble protein expression profiles in rats' and human skeletal muscles with the relative molecular mass of 14 000-230 000 at different time points postmortem. The establishment of multiple PMI estimation models based on multivariate analysis can provide a new idea and method for PMI estimation.

Exploration and Practice of the "One Combination, Two Highlights, Three Combinations, Four in One" Innovative Talents Training Mode in Forensic Medicine

Talent is one of the basic and strategic supports for building a modern socialist country in all aspects. Since the 1980s, the establishment of forensic medicine major and the cultivation of innovative talents in forensic medicine have become hot topics in higher education in forensic medicine. Over the past 43 years, the forensic medicine team of Shanxi Medical University has adhered to the joint education of public security and colleges, and made collaborative innovation, forming a training mode of "One Combination, Two Highlights, Three Combinations, Four in One" for innovative talents in forensic medicine. It has carried out "5+3/X" integrated reform, and formed a relatively complete talent training innovation mode and management system in teaching, scientific research, identification, major, discipline, team, platform and cultural construction. It has made a historic contribution to China's higher forensic education, accumulated valuable experience for the construction of first-class major and first-class discipline of forensic medicine, and provided strong support for the construction of the national new forensic talent training system. The popularization of this training mode is conducive to the rapid and sustainable development of forensic science, and provides more excellent forensic talents for national building, regional social development and the discipline construction of forensic science.

Forensic identification of sudden cardiac death: a new approach combining metabolomics and machine learning

The determination of sudden cardiac death (SCD) is one of the difficult tasks in the forensic practice, especially in the absence of specific morphological changes in the autopsies and histological investigations. In this study, we combined the metabolic characteristics from corpse specimens of cardiac blood and cardiac muscle to predict SCD. Firstly, ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS)-based untargeted metabolomics was applied to obtain the metabolomic profiles of the specimens, and 18 and 16 differential metabolites were identified in the cardiac blood and cardiac muscle from the corpses of those who died of SCD, respectively. Several possible metabolic pathways were proposed to explain these metabolic alterations, including the metabolism of energy, amino acids, and lipids. Then, we validated the capability of these combinations of differential metabolites to distinguish between SCD and non-SCD through multiple machine learning algorithms. The results showed that stacking model integrated differential metabolites featured from the specimens showed the best performance with 92.31% accuracy, 93.08% precision, 92.31% recall, 91.96% F1 score, and 0.92 AUC. Our results revealed that the SCD metabolic signature identified by metabolomics and ensemble learning in cardiac blood and cardiac muscle has potential in SCD post-mortem diagnosis and metabolic mechanism investigations.

[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.

Combined metabolomics and machine learning algorithms to explore metabolic biomarkers for diagnosis of acute myocardial ischemia

Acute myocardial ischemia (AMI) remains the leading cause of death worldwide, and the post-mortem diagnosis of AMI represents a current challenge for both clinical and forensic pathologists. In the present study, the untargeted metabolomics based on ultra-performance liquid chromatography combined with high-resolution mass spectrometry was applied to analyze serum metabolic signatures from AMI in a rat model (n = 10 per group). A total of 28 endogenous metabolites in serum were significantly altered in AMI group relative to control and sham groups. A set of machine learning algorithms, namely gradient tree boosting (GTB), support vector machine (SVM), random forest (RF), logistic regression (LR), and multilayer perceptron (MLP) models, was used to screen the more valuable metabolites from 28 metabolites to optimize the biomarker panel. The results showed that classification accuracy and performance of MLP model were better than other algorithms when the metabolites consisting of L-threonic acid, N-acetyl-L-cysteine, CMPF, glycocholic acid, L-tyrosine, cholic acid, and glycoursodeoxycholic acid. Finally, 17 blood samples from autopsy cases were applied to validate the classification model's value in human samples. The MLP model constructed based on rat dataset achieved accuracy of 88.23%, and ROC of 0.89 for predicting AMI type II in autopsy cases of sudden cardiac death. The results demonstrated that MLP model based on 7 molecular biomarkers had a good diagnostic performance for both AMI rats and autopsy-based blood samples. Thus, the combination of metabolomics and machine learning algorithms provides a novel strategy for AMI diagnosis.

[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 of Linear Regression Model of Gpnmb Gene in Rat Injury Time Estimation

OBJECTIVES

To investigate the effects of injury time, postmortem interval (PMI) and postmortem storage temperature on mRNA expression of glycoprotein non-metastatic melanoma protein B (Gpnmb), and to establish a linear regression model between Gpnmb mRNA expression and injury time, to provide aimed at providing potential indexes for injury time estimation.

METHODS

Test group SD rats were anesthetized and subjected to blunt contusion and randomly divided into 0 h, 4 h, 8 h, 12 h, 16 h, 20 h and 24 h groups after injury, with 18 rats in each group. After cervical dislocation, 6 rats in each group were collected and stored at 0 ℃, 16 ℃ and 26 ℃, respectively. The muscle tissue samples of quadriceps femoris injury were collected at 0 h, 12 h and 24 h postmortem at the same temperature. The grouping method and treatment method of the rats in the validation group were the same as above. The expression of Gpnmb mRNA in rat skeletal muscle was detected by RT-qPCR. The Pearson correlation coefficient was used to evaluate the correlation between Gpnmb mRNA expression and injury time, PMI, and postmortem storage temperature. SPSS 25.0 software was used to construct a linear regression model, and the validation group data was used for the back-substitution test.

RESULTS

The expression of Gpnmb mRNA continued to increase with the prolongation of injury time, and the expression level was highly correlated with injury time (P<0.05), but had little correlation with PMI and postmortem storage temperature (P>0.05). The linear regression equation between injury time (y) and Gpnmb mRNA relative expression (x) was y=0.611 x+4.489. The back-substitution test proved that the prediction of the model was accurate.

CONCLUSIONS

The expression of Gpnmb mRNA is almost not affected by the PMI and postmortem storage temperature, but is mainly related to the time of injury. Therefore, a linear regression model can be established to infer the time of injury.

[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.

Comparison of Medical Dispute Resolution Mechanisms in China and Abroad

Medical disputes are one of the common problems concerned by the whole world. All countries and regions have established their own medical dispute resolution mechanisms, in accordance with their own national conditions. Medical dispute identification opinions, as one of the important bases for identifying the responsibilities of both doctors and patients, play a pivotal role in the process of dispute settlement. A reasonable medical dispute resolution mechanism and standardized medical dispute identification model can help resolve disputes flexibly and reduce the conflict between doctors and patients. This paper briefly compares the medical dispute resolution mechanism and identification mode of China and several other representative countries (the United States, Britain, France, Germany, Italy, Japan, etc.), and discusses their respective characteristics and shortcomings, to bring some enlightenment to the medical dispute resolution and identification in our country.

[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.

Comparison among Four Deep Learning Image Classification Algorithms in AI-based Diatom Test

OBJECTIVES

To select four algorithms with relatively balanced complexity and accuracy among deep learning image classification algorithms for automatic diatom recognition, and to explore the most suitable classification algorithm for diatom recognition to provide data reference for automatic diatom testing research in forensic medicine.

METHODS

The "diatom" and "background" small sample size data set (20 000 images) of digestive fluid smear of corpse lung tissue in water were built to train, validate and test four convolutional neural network (CNN) models, including VGG16, ResNet50, InceptionV3 and Inception-ResNet-V2. The receiver operating characteristic curve (ROC) of subjects and confusion matrixes were drawn, recall rate, precision rate, specificity, accuracy rate and F1 score were calculated, and the performance of each model was systematically evaluated.

RESULTS

The InceptionV3 model achieved much better results than the other three models with a balanced recall rate of 89.80%, a precision rate of 92.58%. The VGG16 and Inception-ResNet-V2 had similar diatom recognition performance. Although the performance of diatom recall and precision detection could not be balanced, the recognition ability was acceptable. ResNet50 had the lowest diatom recognition performance, with a recall rate of 55.35%. In terms of feature extraction, the four models all extracted the features of diatom and background and mainly focused on diatom region as the main identification basis.

CONCLUSIONS

Including the Inception-dependent model, which has stronger directivity and targeting in feature extraction of diatom. The InceptionV3 achieved the best performance on diatom identification and feature extraction compared to the other three models. The InceptionV3 is more suitable for daily forensic diatom examination.

Research Progress of Automatic Diatom Test by Artificial Intelligence

Diatom test is the main laboratory test method in the diagnosis of drowning in forensic medicine. It plays an important role in differentiating the antemortem drowning from the postmortem drowning and inferring drowning site. Artificial intelligence (AI) automatic diatom test is a technological innovation in forensic drowning diagnosis which is based on morphological characteristics of diatom, the application of AI algorithm to automatic identification and classification of diatom in tissues and organs. This paper discusses the morphological diatom test methods and reviews the research progress of automatic diatom recognition and classification involving AI algorithms. AI deep learning algorithm can assist diatom testing to obtain objective, accurate, and efficient qualitative and quantitative analysis results, which is expected to become a new direction of diatom testing research in the drowning of forensic medicine in the future.

Identifying biomarkers for evaluating wound extent and age in the contused muscle of rats using microarray analysis: a pilot study

Wound age estimation is still one of the most important and significant challenges in forensic practice. The extent of wound damage greatly affects the accuracy and reliability of wound age estimation, so it is important to find effective biomarkers to help diagnose wound degree and wound age. In the present study, the gene expression profiles of both mild and severe injuries in 33 rats were assayed at 0, 1, 3, 24, 48, and 168 hours using the Affymetrix microarray system to provide biomarkers for the evaluation of wound age and the extent of the wound. After obtaining thousands of differentially expressed genes, a principal component analysis, the least absolute shrinkage and selection operator, and a time-series analysis were used to select the most predictive prognostic genes. Finally, 15 genes were screened for evaluating the extent of wound damage, and the top 60 genes were also screened for wound age estimation in mild and severe injury. Selected indicators showed good diagnostic performance for identifying the extent of the wound and wound age in a Fisher discriminant analysis. A function analysis showed that the candidate genes were mainly related to cell proliferation and the inflammatory response, primarily IL-17 and the Hematopoietic cell lineage signalling pathway. The results revealed that these genes play an essential role in wound-healing and yield helpful and valuable potential biomarkers for further targeted studies.

Estimating the time of skeletal muscle contusion based on the spatial distribution of neutrophils: a practical approach to forensic problems

The study aimed to explore the neutrophil's spatial distributions used to estimate the histological age of contused skeletal muscle, and assessed the accuracy of various indicators, such as the proportion of neutrophils, "neutrophil mean distance," and distribution of neutrophils in areas of "contiguous contour lines." Fifty-five Sprague-Dawley rats were divided randomly into a control group and contusion groups at 1, 1.5, 2, 3, 4, and 6 h, as well as 1, 3, 5, and 15 days, post-injury (n = 5 per group). Nuclei and neutrophils were detected by hematoxylin and eosin (HE) staining and immunohistochemical (IHC) staining. At 0-24 h after injury, the distribution of neutrophils at distances of 100, 200, 300, 400, 500, and 600 µm from adjacent blood vessels was determined, and the best samples were screened to estimate wound age. To estimate wound age as accurately as possible, Fisher discriminant analysis (FDA) of the proportion of neutrophils, neutrophil mean distance, and distribution of neutrophils was performed, and 100.0% and 95.0% of the original and cross-validated cases were correctly classified, respectively. The spatial distribution of neutrophils at different distances from adjacent blood vessels showed a strong correlation with the histological age of contusion skeletal muscle, and the combination of the proportion of neutrophils, neutrophil mean distance, and distribution of neutrophils could be used to accurately estimate wound age.

Estimating Postmortem Interval Using Intestinal Microbiota Diversity Based on 16S rRNA High-throughput Sequencing Technology

OBJECTIVES

To explore the correlation between intestinal microbiota and postmortem interval(PMI) in rats by using 16S rRNA high-throughput sequencing technology.

METHODS

Rats were killed by anesthesia and placed at 16 ℃, and DNA was extracted in caecum at 14 time points of 0, 1, 2, 3, 5, 7, 9, 12, 15, 18, 21, 24, 27 and 30 d after death. The 16S rRNA high-throughput sequencing technology was used to detect intestinal microbiota in rat cecal contents, and the results were used to analyze the rat intestinal microbiota diversity and differences.

RESULTS

The total number of intestinal microbial communities did not change significantly within 30 days after death, but the diversity showed an upward trend. A total of 119 bacterial communities were significantly changed at 13 time points after death. The models for PMI estimation were established by using partial least squares (PLS) regression at all time points, before 9 days and after 12 days, reaching an R² of 0.795, 0.767 and 0.445, respectively; and the root mean square errors (RMSEs) were 6.57, 1.96 and 5.37 d, respectively.

CONCLUSIONS

Using 16S rRNA high-throughput sequencing technology, the composition and structure of intestinal microbiota changed significantly within 30 d after death. In addition, the established PLS regression model suggested that the PMI was highly correlated with intestinal microbiota composition, showing a certain time series change.

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.