ABSTRACT
Objective Asymptomatic carotid stenosis (ACS) is closely associated to the incidence of severe cerebrovascular diseases. Early identifying the individuals with ACS and its associated risk factors could be beneficial for primary prevention of stroke. This study aimed to investigate a machine-learning algorithm for the detection of ACS among high-risk population of stroke based on the associated risk factors.Methods A novel model of machine learning was utilized to screen the associated predictors of ACS based on 30 potential risk factors. The algorithm of this model adopted a random forest pattern based on the training data and then was verified using the testing data. All of the original data were retrieved from the China National Stroke Screening and Prevention Project (CNSSPP), including demographic, clinical and laboratory characteristics. The individuals with high risk of stroke were enrolled and randomly divided into a training group and a testing group at a ratio of 4:1. The identification of carotid stenosis by carotid artery duplex scans was set as the golden standard. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) was used to evaluate the efficacy of the model in detecting ACS.Results Of 2841 high risk individual of stroke enrolled, 326 (11.6%) were diagnosed as ACS by ultrasonography. The top five risk factors contributing to ACS in this model were identified as family history of dyslipidemia, high level of low-density lipoprotein cholesterol (LDL-c), low level of high-density lipoprotein cholesterol (HDL-c), aging, and low body mass index (BMI). Their weights were 11.8%, 7.6%, 7.1%, 6.1%, and 6.1%, respectively. The total weight of the top 15 risk factors was 85.5%. The AUC values of the model for detecting ACS with training dataset and testing dataset were 0.927 and 0.888, respectively.Conclusions This study demonstrated that the machine-learning algorithm could be used to identify the risk factors for ACS among high risk population of stroke. Family history of dyslipidemia may be the most important risk factor for ACS. This model could be a suitable tool to optimize the clinical approach for the primary prevention of stroke.
ABSTRACT
Objective To study the expression patterns of Th1 and Th2 cytokine genes in childhood acute idiopathic thrombocytopenic purpura(ITP) and its clinical value.Methods Peripheral blood samples from 30 patients with acute ITP before and after treatment (ITP group) and those from 20 normal healthy subjects (healthy control group) were collected (healthy control group),and reverse transcriptases polymerase chain reaction was performed to determine the mRNA expressions of Th1 and Th2 cytokine genes before and after treatment,which were compared with those of the health controls.Results The positive rate of expression levels of Th1 cytokine genes in samples from ITP patients (3.3％,3.3％) were significantly lower than those from healthy control group (all P ＜ 0.05) and increased to normal level after treatment(16.7％,23.3％).In contrast,Th2 cytokine genes (IL-4,IL-6,IL-10)in the samples from the ITP patients(33.3％,43.3％,40.0％) were significantly higher than those from the healthy control group (all P ＜0.05) and decreased after treatment(10.0％,23.3％,20.0％).Conclusions Such data indicate that ITP is a Th2 cell predominant autoimmune disease,and the abnormal immunity due to Th1/Th2 shift is significant in the pathogenesis of ITP.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the inhibitory effect of recombinant adenovirus carrying human endostatin gene (Ad-endo) on the growth of human pancreatic carcinoma xenograft in nude mice.</p><p><b>METHODS</b>The expression of endostatin in human pancreatic carcinoma Capan-2 cells was examined by RT-PCR after infection with Ad-endo. The supernatants of Capan-2 cells were collected after 48 h of infection with Ad-endo as the conditioned medium for human umbilical vein endothelial cells (HUVECs), whose proliferation in vitro was assayed. Capan-2 cell xenografts were established to determine the antitumoral effects of Ad-endo in vivo. The intratumoral microvessel density (MVD) was evaluated using CD31 staining.</p><p><b>RESULTS</b>The expression of endostatin gene was detected by PT-PCR in infected Capan-2 cells. The conditioned medium from Ad-endo-infected cells significantly inhibited HUVEC proliferation (P<0.05). Ad-endo significantly suppressed the growth of Capan-2 tumor xenografts in nude mice (P<0.05), and the MVD decreased significantly in the treated tumor (P<0.05) as compared with that in the control group.</p><p><b>CONCLUSION</b>Adenovirus carrying human endostatin gene produces inhibitory effects on the growth of human pancreatic carcinoma tumors in nude mice.</p>