Aim To explore the impact and mechanism of proprotein convertase subtilisin kexin 9(PCSK9)on the progression of abdominal aortic aneurysm(AAA).Methods 6～8 week old ApoE-/-mice were selected to estab-lish the AAA model.Angiotensin Ⅱ(Ang Ⅱ)was continuously infused through subcutaneous implantation of a micro-os-motic pump.The mice were fed with high-fat diet and killed after 28 days.The expression of PCSK9 in abdominal aor-tic smooth muscle cells was detected by immunohistochemistry and immunofluorescence in normal abdominal aortic blood vessels and AAA samples in human and mice.Primary cultured murine vascular smooth muscle cells(mVSMC)of C57BL/6 mice were treated with different concentrations of AngⅡ for 24 h,and the expression of PCSK9 mRNA and pro-tein was detected.PCSK9 overexpression and knockdown cell models were established,and mitochondrial reactive oxygen species(mtROS),mitochondrial membrane potential(MMP),mitochondrial permeability transition pore(MPTP)open-ing,and Z-DNA binding protein 1(ZBP1)protein expression were detected.Bioinformatics was used to analyze the dif-ferential expression of multiple single-cell sequencing datasets to obtain the key differentially expressed genes,and to study their expression and role in AAA.Results Immunohistochemistry and immunofluorescence results showed that PCSK9 expression in human and mouse AAA increased(P＜0.01),and co-localized with smooth muscle.Ang Ⅱ promoted PCSK9 expression in mVSMC in a concentration-dependent manner,the 2.0 μmol/L Ang Ⅱ group showed a 2.9-fold and 1.1-fold increase in the expression of PCSK9 mRNA and protein,respectively(P＜0.01),with the most significant effect observed.After successfully constructing PCSK9 overexpression and PCSK9 interference mVSMC models,PCSK9 overex-pression led to an increase in intracellular mtROS,a decrease in MMP,an increase in MPTP opening,and a decrease in cellular activity(P＜0.01);PCSK9 knockdown could reduce Ang Ⅱ induced increase in mtROS,decrease in MMP and MPTP opening;compared with the siNC+Ang Ⅱ group,the siPCSK9+Ang Ⅱ group showed a decrease in mtROS and an in-crease in the fluorescence brightness of MMP and MPTP(P＜0.05).Bioinformatics analysis revealed that ZBP1 was a core differentially expressed gene in AAA.Immunohistochemistry and immunofluorescence results showed that ZBP1 ex-pression in human and mouse AAA tissues increased,and co-localized with smooth muscle.Western blot results showed that PCSK9 overexpression or treatment with 2.0 μmol/L Ang Ⅱ could increase ZBP1 protein expression(P＜0.01),while PCSK9 knockdown could alleviate the increased ZBP1 expression caused by AngⅡ(P＜0.05).Conclusion PCSK9 may induce mitochondrial damage in smooth muscle cells,activate downstream molecule ZBP1 to cause cell damage,and promote the development of AAA.

Aim To explore the impact and mechanism of proprotein convertase subtilisin kexin 9(PCSK9)on the progression of abdominal aortic aneurysm(AAA).Methods 6～8 week old ApoE-/-mice were selected to estab-lish the AAA model.Angiotensin Ⅱ(Ang Ⅱ)was continuously infused through subcutaneous implantation of a micro-os-motic pump.The mice were fed with high-fat diet and killed after 28 days.The expression of PCSK9 in abdominal aor-tic smooth muscle cells was detected by immunohistochemistry and immunofluorescence in normal abdominal aortic blood vessels and AAA samples in human and mice.Primary cultured murine vascular smooth muscle cells(mVSMC)of C57BL/6 mice were treated with different concentrations of AngⅡ for 24 h,and the expression of PCSK9 mRNA and pro-tein was detected.PCSK9 overexpression and knockdown cell models were established,and mitochondrial reactive oxygen species(mtROS),mitochondrial membrane potential(MMP),mitochondrial permeability transition pore(MPTP)open-ing,and Z-DNA binding protein 1(ZBP1)protein expression were detected.Bioinformatics was used to analyze the dif-ferential expression of multiple single-cell sequencing datasets to obtain the key differentially expressed genes,and to study their expression and role in AAA.Results Immunohistochemistry and immunofluorescence results showed that PCSK9 expression in human and mouse AAA increased(P＜0.01),and co-localized with smooth muscle.Ang Ⅱ promoted PCSK9 expression in mVSMC in a concentration-dependent manner,the 2.0 μmol/L Ang Ⅱ group showed a 2.9-fold and 1.1-fold increase in the expression of PCSK9 mRNA and protein,respectively(P＜0.01),with the most significant effect observed.After successfully constructing PCSK9 overexpression and PCSK9 interference mVSMC models,PCSK9 overex-pression led to an increase in intracellular mtROS,a decrease in MMP,an increase in MPTP opening,and a decrease in cellular activity(P＜0.01);PCSK9 knockdown could reduce Ang Ⅱ induced increase in mtROS,decrease in MMP and MPTP opening;compared with the siNC+Ang Ⅱ group,the siPCSK9+Ang Ⅱ group showed a decrease in mtROS and an in-crease in the fluorescence brightness of MMP and MPTP(P＜0.05).Bioinformatics analysis revealed that ZBP1 was a core differentially expressed gene in AAA.Immunohistochemistry and immunofluorescence results showed that ZBP1 ex-pression in human and mouse AAA tissues increased,and co-localized with smooth muscle.Western blot results showed that PCSK9 overexpression or treatment with 2.0 μmol/L Ang Ⅱ could increase ZBP1 protein expression(P＜0.01),while PCSK9 knockdown could alleviate the increased ZBP1 expression caused by AngⅡ(P＜0.05).Conclusion PCSK9 may induce mitochondrial damage in smooth muscle cells,activate downstream molecule ZBP1 to cause cell damage,and promote the development of AAA.

Objective:To understand the current status of the use of aspirin in perioperative period of thoracic surgery in China and the awareness of thoracic surgeons on the prevention and treatment of arterial thromboembolic diseases during the perioperative period.Methods:A survey was conducted among thoracic surgeons nationwide using an electronic questionnaire through a software platform from January 20, 2024 to February 29, 2024. The questionnaire mainly included three parts: basic information, aspirin use, and awareness of arterial thromboembolic diseases, with a total of 27 questions.Results:A total of 1318 valid questionnaires were collected, covering all 33 provincial administrative regions except Taiwan. 69.7%(919/1 318) of thoracic surgeons stopped using aspirin for all patients before surgery; differences could be found in the timing of aspirin withdrawal before surgery and resumption after surgery. 65.1%(858/1 318) of surgeons made perioperative medication decisions based on domestic guidelines or consensus, while 20.9%(276/1 318) of surgeons based their decisions on departmental or personal experience. 87.9%(1 159/1 318) of surgeons believed that it is necessary to develop guidelines for the prevention of arterial thromboembolic diseases in the perioperative period of thoracic surgery.Conclusion:The current use strategy of aspirin in the perioperative period of thoracic surgery in China shows a high degree of inconsistency, and there are also significant differences in the awareness of arterial thromboembolic diseases. It is necessary to establish guidelines for the prevention and treatment of arterial thromboembolic diseases in the perioperative period.

Objective:To develop a risk prediction model for identifying bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PH) in very premature infants.Methods:This was a retrospective cohort study. The clinical data of 626 very premature infants whose gestational age <32 weeks and who suffered from BPD were collected from October 1 st, 2015 to December 31 st, 2021 of the Seventh Medical Center of the People′s Liberation Army General Hospital as a modeling set. The clinical data of 229 very premature infants with BPD of Hunan Children′s Hospital from January 1 st, 2020 to December 31 st, 2021 were collected as a validation set for external verification. The very premature infants with BPD were divided into PH group and non PH group based on the echocardiogram after 36 weeks′ corrected age in the modeling set and validation set, respectively. Univariate analysis was used to compare the basic clinical characteristics between groups, and collinearity exclusion was carried out between variables. The risk factors of BPD associated PH were further screened out by multivariate Logistic regression, and the risk assessment model was established based on these variables. The receiver operating characteristic (ROC) area under curve (AUC) and Hosmer-Lemeshow goodness-of-fit test were used to evaluate the model′s discrimination and calibration power, respectively. And the calibration curve was used to evaluate the accuracy of the model and draw the nomogram. The bootstrap repeated sampling method was used for internal verification. Finally, decision curve analysis (DCA) to evaluate the clinical practicability of the model was used. Results:A total of 626 very premature infants with BPD were included for modeling set, including 85 very premature infants in the PH group and 541 very premature infants in the non PH group. A total of 229 very premature infants with BPD were included for validation set, including 24 very premature infants in the PH group and 205 very premature infants in the non PH group. Univariate analysis of the modeling set found that 22 variables, such as artificial conception, fetal distress, gestational age, birth weight, small for gestational age, 1 minute Apgar score ≤7, antenatal corticosteroids, placental abruption, oligohydramnios, multiple pulmonary surfactant, neonatal respiratory distress syndrome (NRDS)>stage Ⅱ, early pulmonary hypertension, moderate-severe BPD, and hemodynamically significant patent ductus arteriosus (hsPDA) all had statistically significant influence between the PH group and the non PH group (all P<0.05). Antenatal corticosteroids, fetal distress, NRDS >stage Ⅱ, hsPDA, pneumonia and days of invasive mechanical ventilation were identified as predictive variables and finally included to establish the Logistic regression model. The AUC of this model was 0.86 (95% CI 0.82-0.90), the cut-off value was 0.17, the sensitivity was 0.77, and the specificity was 0.84. Hosmer-Lemeshow goodness-of-fit test showed that P>0.05. The AUC for external validation was 0.88, and the Hosmer-Lemeshow goodness-of-fit test suggested P>0.05. Conclusions:A high sensitivity and specificity risk prediction model of PBD associated PH in very premature infants was established. This predictive model is useful for early clinical identification of infants at high risk of BPD associated PH.

Objective:To investigate the clinical value of fascia orientated laparoscopic lateral lymph node dissection (LLND) in radical excision for advanced low rectal cancer.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 100 patients with advanced low rectal cancer who were admitted to Peking University First Hospital from January 2013 to August 2021 were collected. There were 69 males and 31 females, aged 58(range, 32?85)years. Patients underwent laparoscopic total mesorectal excision and fascia oriented LLND. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) results of histopathological exa-mination; (4) follow-up. Follow-up was conducted by telephone interview, outpatient examination and medical records review to detect survival, disease progression, tumor recurrence and metastasis of patients up to August 2021. Survival time was from the surgery date to death or the last follow-up time of patients. Measurement data were represented as M(range). Count data were represented as absolute numbers. Kaplan-Meier method was used to draw survival curves and calculate survival rates. Results:(1) Surgical situations. Of the 100 patients, 44 cases underwent neoadjuvant therapy and 56 cases didn′t receive preoperative therapy. Of the 100 patients with laparoscopic radical excision for advanced low rectal cancer, 60 cases underwent low anterior resection of rectal cancer including 49 cases with unilateral LLND and 11 cases with bilateral LLND,20 cases underwent abdomin-operineal resection for rectal cancer including 16 cases with unilateral LLND and 4 cases with bilateral LLND, 12 cases underwent total pelvic exenteration including 6 cases with unilateral LLND and 6 cases with bilateral LLND, 5 cases underwent Hartmann surgery including 3 cases with unilateral LLND and 2 cases with bilateral LLND, 3 cases underwent posterior pelvic exenteration including 2 cases with unilateral LLND and 1 case with bilateral LLND. The operation time and volume of intraoperative blood loss were 258(range,200?325)minutes and 100(range, 50?200)mL. There were 19 patients with low anterior resection of rectal cancer and protective ileostomy simultaneously. Three patients encountered intraoperative lymph node invasion of the obturator nerve, causing injury of the nerve at dissection. Of the 100 patients, 12 cases with total pelvic exenteration were dissected the ureterohypogastric nerve fascia and 88 cases were preserved the complete ureterohypogastric nerve fascia. (2) Postoperative situations. There was no perioperative death in the 100 patients. The time to postoperative catheter removal and duration of hospital stay of the 100 patients were 4(range, 3?7)days and 11(range, 9?15)days, respectively. There were 26 cases with postoperative complications. (3) Results of histopathological examination. The maximum tumor diameter was 4.5(range, 3.8?5.9)cm. There were 21 patients with mass type of tumor pross and 79 cases with ulcerative type. There were 82 cases with high and moderate differentiation of tumor differentiation degree, 18 cases with low differentiation and undifferentiated adenocarcinoma (signet ring cell carcinoma). There were 14 cases in TNM stage Ⅰ, 38 cases in TNM stage Ⅱ, 48 cases in TNM stage Ⅲ. There were 16 cases in stage T0?2 and 84 cases in stage T3?4. There were 52 cases in stage N0 and 48 cases in stage N1?2. The total number of lymph node dissected was 23(range, 18?27)per person and the total number of unilateral LLND was 5(range, 3?9)per person. There were 36 of 100 patients with positive lateral lymph nodes, including 14 cases with neoadjuvant therapy. (4) Follow-up. Of the 100 patients, 97 cases were followed up for 21(range, 1?69)months. The 2-year overall survival rate was 81.6% and 2-year disease progression free survival rate was 70.6%. During the follow-up, 4 of 97 patients had presacral tumor recurrence and 1 case had tumor recurrence in the LLND region. There were 11 cases with liver metastasis, 5 cases with bone metastasis, 2 cases with the contralateral lymph node metastasis of unilateral LLND, 2 cases with paraaortic lymph node metastasis, 2 cases with transcoelomic spread. Of the 97 patients who were followed up, 76 cases survived with free disease, 4 cases survived with tumor, 15 cases died of tumor and 2 cases died of other diseases.Conclusion:The fascia orientated laparoscopic LLND is safe and feasible in radical excision for advanced low rectal cancer.

Objective:To evaluate CT and or MRI imaging in the diagnosis of lateral lymph node metastasis in patients of middle and low rectal cancer.Methods:In this study, 112 lateral lymph nodes were harvested in 79 patients with middle and low rectal cancer. The relationship between the preoperative imaging features of the lateral lymph nodes and the postoperative pathology was evaluated.Result:Thirty-eight cases (48%) were pathologically confirmed to have lateral lymph node metastasis. The diameter of metastasis-positive lateral lymph nodes was significantly larger than that of metastasis-negative lateral lymph nodes ( P<0.01). Multivariate analysis of clinical features and imaging features found that, tumors poorly differentiated, mucinous adenocarcinoma, signet ring cell carcinoma ( P=0.006), and the largest short diameter of the lateral lymph node ≥7 mm ( P=0.024), uneven density or signal ( P=0.022) were independent risk factors for lateral lymph node metastasis. Conclusion:Poor tumor differentiation, lateral lymph node maximum short diameter ≥7 mm, density or signal unevenness are independent risk factors for lateral lymph node metastasis in middle and low rectal carcinoma.

Objective:To explore the application of digital acoustic analysis in assessing the risk of aspiration among persons with dysphagia using the Praat speech analysis software.Methods:The swallowing of 46 stroke survivors with dysphagia was studied using video fluoroscopy. Each patient was required to pronounce " yi/i/" 3 times before and after taking each mouthful of food, and their voice samples were collected. The subjects were divided into a non-aspiration group of 16 and an aspiration group of 30 based on their penetration-aspiration scale scores. Fundamental frequency, relative average perturbation (RAP), jitter, shimmer, amplitude perturbation quotient and harmonic-to-noise ratio were compared between the two groups before and after taking food.Results:For the non-aspiration group, there was no significant difference in the acoustic data before and after eating. For the aspiration group there were significant differences in fundamental frequency, relative average perturbation and jitter before and after taking food. The average RAP and jitter of the non-aspiration group were significantly better than the aspiration group′s averages before eating. After eating, however, significant differences were observed only in average jitter.Conclusions:Analyzing perturbation and jitter can help to identify persons at risk of aspiration.

A novel coronavirus pneumonia (NCP) epidemic has occurred in Wuhan, Hubei Province since December 2019, caused by a novel coronavirus (2019-nCoV) never been seen previously in human. China has imposed the strictest quarantine and closed management measures in history to control the spreading of the disease. However, severe trauma can still occur in the NCP patients. In order to standardize the emergency treatment and the infection prevention and control of severe trauma patients with hidden infection, suspected or confirmed infection of 2019-nCoV, Trauma Surgery Branch of Chinese Medical Doctors' Association organized this expert consensus. The consensus illustrated the classification of the NCP patients, severe trauma patients in need of emergency surgery, emergency surgery type, hierarchical protection for medical personnel and treatment places. Meanwhile, the consensus standardized the screening, injury severity evaluation, emergency surgical treatment strategy and postoperative management strategy of severe trauma patients during the epidemic period of NCP, providing a basis for the clinical treatment of such kind of patients.

Objective:To evaluate the relationship between decreased atrial myoelectric conduction and gap junction protein 40 (Cx40) and Cx43 in rats with reperfusion atrial arrhythmia.Methods:Sixteen Langendorff-isolated heart perfusion models were randomly divided into control group (group C) and ischemia-reperfusion group (group IR), with 8 rats in each group.According to whether the atrial arrhythmia occurred after reperfusion, group IR was further divided into reperfusion non-atrial arrhythmia subgroup (group R-NAA) and reperfusion atrial arrhythmia subgroup (group R-AA). Group C was balanced perfusion with K-H solution (37 ℃) for 120 min.In group IR, hearts were perfused with K-H solution (37 ℃) for 30 min, perfusion was then stopped, Thomas solution (4 ℃, 20 ml/kg) was injected to induce cardiac arrest for 60 min, the surrounding of the heart was protected with 4 ℃Thomas solution, and hearts were perfused with Thomas solution (4 ℃, 10 ml/kg) again after 30 min of cardiac arrest and then with K-H solution 37 ℃ for 30 min.At 120 min of equilibration or 30 min of reperfusion, the effective refractory period (ERP) and conduction velocity (CV) of the right atrium were measured, the expression of Cx40 and Cx43 in the right atrial myocardium was detected by Western blot, and ratio of Cx40 to Cx40+ Cx43 and the ratio of Cx43 to Cx40+ Cx43 were calculated.Results:The incidence of reperfusion atrial arrhythmia was 38% in group IR.Compared with group C, ERP was significantly prolonged, CV was decreased, the expression of Cx40 and Cx43 was down-regulated, the ratio of Cx40 to Cx40+ Cx43 was increased, and the ratio of Cx43 to Cx40+ Cx43 was decreased in R-NAA and R-AA groups ( P<0.05). Compared with group R-NAA, ERP was significantly prolonged, CV was decreased, the expression of Cx40 and Cx43 was down-regulated, the ratio of Cx40 to Cx40+ Cx43 was increased, and the ratio of Cx43 to Cx40+ Cx43 was decreased in group R-AA ( P<0.05). Conclusion:The decreased atrial myoelectric conduction may be related to the down-regulation of Cx40 and Cx43 expression in rats with reperfusion atrial arrhythmia.