Objective:To explore the key factors affecting plasma clot retraction and optimize the experimental method of plasma clot retraction,in order to study the regulation of platelet function and evaluate the modulatory effects of drugs on plasma clot retraction.Methods:The effects of different concentrations of thrombin,Ca2+and platelets on plasma clot retraction were studied,and the detection system of plasma clot retraction was optimized.The availability of the detection system was then validated by analyzing the regulatory effects of multiple signaling pathway inhibitors on plasma clot retraction.Results:Through the optimization study of multiple factors,platelet rich plasma(PRP)containing 0.5 mmol/L Ca2+and 40 × 109/L platelets was treated with 0.2 U/ml thrombin to perform plasma clot retraction analysis.After treatment with thrombin for 15 min,plasma clot retracted significantly.After treatment with thrombin for 30 min,the percentage of plasma clot retraction was more than 50％.The regulatory effects of multiple signaling pathway inhibitors on plasma clot retraction were studied in this detection system.PKC inhibitor Go 6983 exhibited a significant inhibitory effect on plasma clot retraction,while PI3K inhibitor Ly294002 and p38 MAPK inhibitor SB203580 slightly suppressed plasma clot retraction.Conclusion:PRP containing 0.5 mmol/L Ca2+and 40 × 109/L platelets can be induced with 0.2 U/ml thrombin to conduct plasma clot retraction analysis,which can be used to study the regulation of platelet function and evaluate the modulatory effects of drugs on plasma clot retraction.

Objective:To investigate the molecular mechanism and distribution characteristics of RhD negative phenotypes in Han population of blood donors in Wuhu city.Methods:A total of 210 RhD-samples from August 2021 to August 2022 were screened by serological test and collected from Wuhu Central Blood Station for the voluntary blood donor population.Exons 1 and 10 of the RHD gene were amplificated by PCR to determine whether the samples had the RHD gene.Exons 1-10 of the RHD gene were amplificated by PCR and zygosity analysis were performed in 82 samples containing D gene,and Sanger sequencing was performed on 55 samples containing all RHD exons to determine the genotype.Results:Among 210 RhD-specimens,128 cases(60.38％)had RHD gene deletion.27 cases had partial exons of RHD,including 2 cases with RHD*DVI.3/RHD*01N.01,24 cases with RHD*01N.04/RHD*01N.01,and 1 case with RHD-CE(2-10)/RHD*01N.01.55 cases had retained all of 10 exons,including 4 cases with RHD*01/RHD*01N.01,6 cases with RHD*15/RHD*01N.01,1 case with RHD*01W.72/RHD*01N.01,1 case with RHD*15/RHD*01EL.01,39 cases with RHD*01EL.01/RHD*01N.01,and the remaining 4 cases were determined to have no RHD gene deletion by zygosity analysis and sequencing showed the presence of 1227G＞A mutation loci.Conclusion:There is polymorphism in the molecular mechanism of RhD-D gene in Wuhu blood donor population,among which RHD*01EL.01 and RHD*15 are the main variants in this region.The results of this study provide a theoretical basis for RhD blood group identification and clinical blood transfusion in this region.

Objective:To study the molecular mechanism of functional defect of protein C (PC) caused by point mutations of human protein C gene (PROC) N355S,G392E and T314A. Methods:The wild-type and mutant plasmids (PCWT,PCN355S,PCG392E,PCT314A) of PROC gene were constructed and transiently transfected into HEK293 cells. The expression of mutant proteins in vitro were tested. The mRNA level changes of wild-type and mutant PC after 24 h of transfection were detected by real-time PCR. Western blot and ELISA were used to detect the changes of intracellular and extracellular protein levels of wild-type and mutant PC. The supernatant of cells transfected for 24-48 h was concentrated by ultrafiltration. The protein in the concentrated solution was quantified,and PC activation and enzyme kinetics tests were performed. Clustal Omega multiple sequence alignment was used to analyze the conservation of amino acid mutation sites. The effect of mutation on PC protein structure was analyzed by PyMOL software. Results:The relative expression abundances of PROC mRNA in PCN355S,PCG392E and PCT314A groups were 1.14±0.46,0.96±0.08 and 1.08±0.17,respectively,and there were no significant differences compared with 1.02±0.24 in PCWT group (P>0.05). Western blot analysis of the lysates of transfected cells showed that the content of PCT314A recombinant protein slightly decreased and the band became relatively lighter. The ELISA results of the concentrated cell culture supernatants showed that the PC:Ag levels of PCN355S and PCG392E were 98.8％±2.4％ and 101.4％±3.1％,respectively,with no significant differences compared with PCWT,while PCT314A decreased compared with PCWT (PC:Ag:88.6％±3.2％) (P<0.05). The results of enzyme kinetics test showed that APCN355S (Km=338.3±43.2,Vmax=2.015±0.12),APCG392E (Km=292.2±28.4,Vmax=1.893±0.07) and APCT314A (Km=299.5±24.6,Vmax=1.775±0.06) showed an increase in Km and a decrease in Vmax compared with APCWT (Km=238.2±4.58,Vmax=3.205±0.06). Multiple sequence alignment suggested that the three mutations be highly conservative in different species. The structural model suggested that the amino acid substitutions of N355S,G392E and T314A mutations collide with the surrounding amino acid groups,causing distortion of the surrounding structure,which may have adverse effects on the folding and biological function of PC. Conclusion:The N355S,G392E and T314A mutations in the PROC gene cause functional defects in PC by weakening the binding between PC and substrate. These three mutations have caused serious spatial collisions in the protein structure,affecting the folding of PC and the reactivity of active sites.

Objective:To construct and validate the best predictive model for 28-day death risk in patients with septic shock based on different supervised machine learning algorithms.Methods:The patients with septic shock meeting the Sepsis-3 criteria were selected from Medical Information Mart for Intensive Care-Ⅳ v2.0 (MIMIC-Ⅳ v2.0). According to the principle of random allocation, 70% of these patients were used as the training set, and 30% as the validation set. Relevant predictive variables were extracted from three aspects: demographic characteristics and basic vital signs, serum indicators within 24 hours of intensive care unit (ICU) admission and complications possibly affecting indicators, functional scoring and advanced life support. The predictive efficacy of models constructed using five mainstream machine learning algorithms including decision tree classification and regression tree (CART), random forest (RF), support vector machine (SVM), linear regression (LR), and super learner [SL; combined CART, RF and extreme gradient boosting (XGBoost)] for 28-day death in patients with septic shock was compared, and the best algorithm model was selected. The optimal predictive variables were determined by intersecting the results from LASSO regression, RF, and XGBoost algorithms, and a predictive model was constructed. The predictive efficacy of the model was validated by drawing receiver operator characteristic curve (ROC curve), the accuracy of the model was assessed using calibration curves, and the practicality of the model was verified through decision curve analysis (DCA).Results:A total of 3?295 patients with septic shock were included, with 2?164 surviving and 1?131 dying within 28 days, resulting in a mortality of 34.32%. Of these, 2?307 were in the training set (with 792 deaths within 28 days, a mortality of 34.33%), and 988 in the validation set (with 339 deaths within 28 days, a mortality of 34.31%). Five machine learning models were established based on the training set data. After including variables at three aspects, the area under the ROC curve (AUC) of RF, SVM, and LR machine learning algorithm models for predicting 28-day death in septic shock patients in the validation set was 0.823 [95% confidence interval (95% CI) was 0.795-0.849], 0.823 (95% CI was 0.796-0.849), and 0.810 (95% CI was 0.782-0.838), respectively, which were higher than that of the CART algorithm model (AUC = 0.750, 95% CI was 0.717-0.782) and SL algorithm model (AUC = 0.756, 95% CI was 0.724-0.789). Thus above three algorithm models were determined to be the best algorithm models. After integrating variables from three aspects, 16 optimal predictive variables were identified through intersection by LASSO regression, RF, and XGBoost algorithms, including the highest pH value, the highest albumin (Alb), the highest body temperature, the lowest lactic acid (Lac), the highest Lac, the highest serum creatinine (SCr), the highest Ca 2+, the lowest hemoglobin (Hb), the lowest white blood cell count (WBC), age, simplified acute physiology score Ⅲ (SAPSⅢ), the highest WBC, acute physiology score Ⅲ (APSⅢ), the lowest Na +, body mass index (BMI), and the shortest activated partial thromboplastin time (APTT) within 24 hours of ICU admission. ROC curve analysis showed that the Logistic regression model constructed with above 16 optimal predictive variables was the best predictive model, with an AUC of 0.806 (95% CI was 0.778-0.835) in the validation set. The calibration curve and DCA curve showed that this model had high accuracy and the highest net benefit could reach 0.3, which was significantly outperforming traditional models based on single functional score [APSⅢ score, SAPSⅢ score, and sequential organ failure assessment (SOFA) score] with AUC (95% CI) of 0.746 (0.715-0.778), 0.765 (0.734-0.796), and 0.625 (0.589-0.661), respectively. Conclusions:The Logistic regression model, constructed using 16 optimal predictive variables including pH value, Alb, body temperature, Lac, SCr, Ca 2+, Hb, WBC, SAPSⅢ score, APSⅢ score, Na +, BMI, and APTT, is identified as the best predictive model for the 28-day death risk in patients with septic shock. Its performance is stable, with high discriminative ability and accuracy.

Objective:To investigate the factors influencing recipient liver regeneration after full-size split liver transplantation (fSLT).Methods:The clinical data of patients undergoing split liver transplantation in the Affiliated Li Huili Hospital of Ningbo University from May 2019 to Sep 2023 were retrospectively collected. Graft volume (GV) and initial graft volume (IGV) at (30±7) days after operation were measured, and postoperative liver regeneration rate (LRR) was calculated. The patients undergoing fSLT were divided into high regeneration group and low regeneration group with LRR=30% as boundary. The differences of donor and recipient data and perioperative data between the two groups were compared.Results:A total of 52 patients were included. The low fSLT regeneration group (16 cases) was compared with the high fSLT regeneration group (36 cases), and in high fSLT regeneration group donor age was lower, the donor liver steatosis was less, GRWR was lower, the incidence of hepatitis B virus-related liver disease was lower, the postoperative diagnosis of malignant liver disease was lower, the intraoperative blood loss was less, and the postoperative platelet count was higher. The levels of liver enzyme and total bilirubin (TBiL) were higher than those in high regeneration group ( P<0.05). Conclusions:Donor age, donor liver steatosis, GRWR, hepatitis B virus associated liver disease, and recipient pathogenesis are important factors affecting liver regeneration after fSLT. Postoperative platelet and liver enzyme levels are important indicators for monitoring liver regeneration after fSLT.

Objective:To explore the mechanism of herb-partitioned moxibustion in relieving rat intestinal inflammation by focusing on the neutrophil extracellular traps(NETs)in Crohn disease(CD)development. Methods:Rats were randomly divided into a normal group,a model group,a herb-partitioned moxibustion group,and a mesalazine group.The CD rat model was prepared with 2,4,6-trinitrobenzene sulfonic acid except for rats in the normal group.Rats in the normal group and model group did not receive any treatment but had the same fixation as the other groups.Rats in the herb-partitioned moxibustion group received herb-partitioned moxibustion at Qihai(CV6)and bilateral Tianshu(ST25).Rats in the mesalazine group received intragastric administration of mesalazine enteric-coated tablets.The general situation of rats in each group was recorded,and the histopathological changes in the colon were observed and scored by hematoxylin-eosin staining.The serum concentrations of NETs DNA(NETs-DNA),neutrophil elastase(NE)-DNA,and myeloperoxidase(MPO)-DNA were detected by ABC enzyme-linked immunosorbent assay,and the citrullinated histone 3(citH3),MPO,and NE protein and mRNA expression levels in rat colon tissue were observed by immunofluorescence and real-time quantitative polymerase chain reaction. Results:Compared with the normal group,the mucosal ulcer reached the muscularis,the epithelium was incomplete,the goblet cells decreased obviously with significant inflammatory cell infiltration in the colon;the colonic mucosa damage index(CMDI)score increased significantly(P<0.01);the serum NETs-DNA,NE-DNA,and MPO-DNA concentrations increased(P<0.05);the NE,citH3,and MPO protein and mRNA expression in the colonic tissue increased significantly in the model group(P<0.01 or P<0.05).Compared with the model group,the mucosal epithelium in the herb-partitioned moxibustion group and the mesalazine group was repaired and the goblet cells increased with a few infiltrating inflammatory cells in the colon;the CMDI score decreased(P<0.01);the serum NETs-DNA,NE-DNA,and MPO-DNA concentrations decreased(P<0.05);the NE,citH3,and MPO protein and mRNA expression in the colonic tissue was down-regulated(P<0.01 or P<0.05). Conclusion:Herb-partitioned moxibustion reduced the serum NETs complex and inhibited the protein and mRNA expression of NETs complex in the colon tissue,which may be one mechanism of herb-partitioned moxibustion in relieving colon mucosal inflammation in CD.

Objective:To investigate the role of serotonin reuptake transporter(SERT)and P2X3 receptor of dorsal root ganglion(DRG)in regulating visceral hypersensitivity of rats with irritable bowel syndrome(IBS)by electroacupuncture(EA). Methods:Male Sprague-Dawley and SERT-/-rats were subjected to preparing IBS visceral hypersensitivity models with 2,4,6-trinitrobenzene sulfonic acid(TNBS)enema.Three weeks post-modeling,interventions including EA,intrathecal injection,and EA plus intrathecal injection were applied,respectively.Hematoxylin-eosin staining and abdominal withdrawal reflex(AWR)score were used to confirm the successful establishment of the IBS model.AWR score,whole-cell patch clamp technique,and Western blotting assay were used to evaluate the changes in visceral pain sensitivity,electrophysiological properties of DRG neurons,and the expression of DRG P2X3 receptor and SERT in IBS rats. Results:Compared to the model group,the AWR score in the EA group decreased significantly(P<0.05),the resting membrane potential(P<0.05)and the number of action potentials(P<0.05)of DRG neurons reduced,and the baseline intensity increased(P<0.05);additionally,the expression of P2X3 receptor in DRG decreased(P<0.01),and the SERT expression increased(P<0.05).Compared to the P2X3 receptor agonist group,the SERT protein expression in DRG was higher in the EA group.In SERT-/-rats,the P2X3 receptor expression in DRG increased in the EA group compared to the model group(P<0.01). Conclusion:EA modulates the electrophysiological characteristics of intestinal primary sensory neurons by regulating the expression of SERT and P2X3 receptor in DRG of IBS rats.This modulation may contribute to the mechanism by which EA alleviates peripheral sensitization of visceral pain in IBS rats.

Objective:Exploring the dilemmas faced by adolescents with type 1 diabetes mellitus in self-management during the transition to adult healthcare, to inform healthcare professionals in the delivery of transitional care interventions.Methods:Using descriptive qualitative research methods, in-depth interviews were conducted from August to December 2023 to adolescents with type 1 diabetes mellitus (selected by objective sampling) who met the inclusion and exclusion criteria in the Department of Endocrinology of the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine and the Shenzhen Children′s Hospital, and the data were analysed inductively using directed content analysis.Results:A total of 12 adolescents with type 1 diabetes mellitus were included for interview, 6 males and 6 females, aged 12-18 years. The self-management dilemmas for adolescents with type 1 diabetes in the transition to adult healthcare can be summarised into 4 themes and 10 sub-themes: disease management dilemmas (weak awareness of disease management, insufficient disease-related knowledge and competence, low adherence to disease management, and restriction of daily activities), role adaptation difficulties (lack of perceived transition to the healthcare role, difficulty in transitioning to the family role, and maladaptation to the social role), negative emotions Inadequate social support system (lack of school support, limited accessibility of social organisations, insufficient socio-economic support).Conclusions:Adolescents with type 1 diabetes mellitus face multiple dilemmas in disease self-management during the transition to adult healthcare, and healthcare professionals should pay attention to transition self-management education, improve patients′ awareness of transition self-management and their ability to participate in it, formulate a transition preparation plan, build an emotional support network, and improve the social security system, so as to help juvenile patients with type 1 diabetes master the method of self-management and make a successful transition to adulthood.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Aim To investigate whether SIRT6 overexpression inhibits angiotensin Ⅱ(Ang Ⅱ)-induced cardio-myocyte apoptosis by activating adenosine 5'-monophosphate-activated protein kinase/nuclear factor erythroid 2-related factor 2/heme oxygenase-1(AMPK/Nrf2/HO-1)signaling pathway.Methods The experiment was divided into 4 groups:control group,AngⅡ group,Ang Ⅱ+SIRT6 group,Ang Ⅱ+empty vector(EV)group.The mRNA level of SIRT6 was detected by RT-PCR.The cell activity was measured by MTT assay.The cell apoptosis was analyzed by flow cy-tometry.SIRT6,cardiomyocyte apoptosis related proteins(Bax,cleaved Caspase-3,Bcl-2),DNA damage related pro-teins(γ-H2AX,p-ATM),AMPK/Nrf2/HO-1 signaling pathway related proteins(p-AMPK,Nrf2,HO-1)were measured by Western blot.The reactive oxygen species(ROS)content was determined by DCFH-DA staining.The changes of the above indexes among the groups were observed.Results Compared with control group,the mRNA and protein ex-pression levels of SIRT6 and cell activity were significantly decreased in Ang Ⅱ group.Apoptosis rate,the expressions of Bax,cleaved Caspase-3 were increased,and the expression of Bcl-2 was decreased.The expressions of γ-H2AX and p-ATM were increased,and the expressions of p-AMPK,Nrf2,HO-1 were decreased.The activity of ROS was increased(P＜0.01).Compared with Ang Ⅱ+EV group,the expression of SIRT6 and cell activity were significantly increased in Ang Ⅱ+SIRT6 group.Apoptosis rate,the expressions of Bax and cleaved Caspase-3 were decreased,and the expression of Bcl-2 was increased.The expressions of γ-H2AX and p-ATM were decreased,the expressions of p-AMPK,Nrf2,HO-1 were increased.The activity of ROS was decreased(P＜0.01).Conclusion SIRT6 overexpression inhibits Ang Ⅱ-induced cardiomyocyte apoptosis through activation of AMPK/Nrf2/HO-1 signaling pathway.