Objective To establish rat models with pulmonary artery hypertension induced by monocrotaline(MCT) and to observe the pathological changes of lung tissue.Methods Seventy male Wistar rats were randomly devided into three group:control group(n=10),50 mg?kg-1 MCT group(n=30),60 mg?kg-1 MCT group(n=30).At two weeks and four weeks after injected intraperitoneally with MCT(injected intraperitoneally with equal normal saline in control group),the right ventricular systolic pressure(RVSP)and right ventricle weight/left ventricle+septum weight [RV/(LV+S)] ratio were measured.Hematoxylin-eosin staining and orcein technique were used to observe the pathological changes of lung tissue and pulmonary arterioles'medial thickness.Results Two weeks or four weeks after MCT administration,RVSP in 50 mg?kg-1 MCT group was higher than that in control group(respectively 36.6 mmHg?5.1 mmHg,39.1 mmHg?7.0 mmHg versus 26.1 mmHg?3.8 mmHg,both P

AIM and METHODS: After the fine carbon fiber powder was injected into the right subdural space of the mice, dynamic observation was carried out on their movement and histopathological changes. RESULTS: 1-52 weeks after the injecting, no neurological changes concerning with the implanting of the carbon fiber powder were found in the experimental mice. The fine carbon fiber extensively located on the inter surface of the dura mater membrane of the right temporalis and the out surface of pie mater. Only slight inflammatory cells reaction was found under optical microscopes. The degree of inflammation reaction are Grade Ⅱ 1 week after injection and was Grade Ⅰ 2 weeks after injection, inflammation was disappeared 4 weeks after injection. No obvious fiber membrane was found around the implanted materials. No significant differences were found between the experimental and the control group.CONCLUSION: It was showed that the carbon fiber shares excellent histocompatibility after injected into the subdural space and subarechnoid cavity of the right temple of mice.

Following Escherichia coli lysis with alkali, cetyltrimethylammonium bromide (CTAB) was directly titrated into the supernatant. An easy and feasible technology for plasmid purification was established with the optimized proportion between the quantity of CTAB and plasmid, combined with the specific solution for DNA release and TritonX-114 for endotoxin removal. Quality detection showed that the purified plasmid was free of contamination of host RNA. The host bacterial genomic DNA, endotoxin and bacterial protein were less than 10 microg, 50 EU and 10 microg per mg plasmids, respectively. The ratio of OD260/OD280 was between 1.75-1.85. Eighty percent of the prepared plasmids were presented in the supercoiled form. The plasmid purified with this technology can satisfy all criteria stipulated by FDA. The main advantages of the technology include the avoidance of animal-derived enzymes such as ribonucleases A, Proteinase K and toxic reagents like chloroform and phenol. In addition, the technology has low cost and no pollution.
Cetrimonium Compounds ; chemistry ; Chemical Precipitation ; DNA ; genetics ; isolation & purification ; DNA, Bacterial ; genetics ; isolation & purification ; Escherichia coli ; chemistry ; genetics ; Plasmids ; genetics ; isolation & purification

Objective To create a mouse model of colorectal polyps with Apc-Kras-Cre gene mutations using the tamoxifen induction method.Methods Mice with Apc-Kras-Cre mutations were divided into four groups and injected intraperitoneally with different concentrations and dosages of tamoxifen for different durations,with group 1 injected with low dosage tamoxifen(5 mg/kg)for 1 day,group 2 injected with low dosage tamoxifen(5 mg/kg)for 3 days,group 3 injected with high dosage tamoxifen(50 mg/kg)for 1 day,group 4 injected with high dosage tamoxifen(50 mg/kg)for 3 days.C57BL/6J mice were used as a healthy control group and survival and changes in body weight were observed.All mice were euthanized 4 weeks post-tamoxifen induction and the colon length and number and size of intestinal polyps were observed.Histological changes in the intestinal tissue and polyps were detected by hematoxylin and eosin staining.Results The survival rate of male mice was higher(P＜0.001)and the morbidity rate of male mice was lower compared with female mice(P＜0.05).The survival rate differed significantly among the four groups(P＜0.01).All groups showed significant changes in body weight compared with the healthy control group(P＜0.001).There were also significant differences in weight changes between tamoxifen-induced groups 1 and 2,between groups 2 and 3,and between groups 1 and 4(P＜0.001,P＜0.01,P＜0.05,respectively).There were no significant differences in colon length between any treated group and the healthy control group(P＞0.05),but colon length did differ between tamoxifen-induced groups 1 and 3(P＜0.05).Polyp size varied in each group of tamoxifen-treated mice,with most polyps occuring at the distal end of the colon,while mice in groups 3 and 4 had more and larger polyps.Histopathological examination showed intestinal polyps with uneven and misaligned glandular and epithelial arrangements,a loosely-packed intestinal mucosal barrier,and irregularly-distributed crypts in tamoxifen-induced mice compared with the healthy control group,while mice in tamoxifen-induced groups 3 and 4 showed signs of inflammation and mice in group 4 showed necrosis of cells in some regions.Conclusions Tamoxifen-induced Apc-Kras-Cre model mice were successfully established,with the group 3 induction method being the most suitable.

Objective:To investigate the percutaneous permeability of sinomenine hydrochloride （SNH） and optimize the parameters of electroporation to achieve the best permeation enhancing effect on SNH. Method:The percutaneous permeability of SNH and the enhancement effect of electroporation were studied by in vitro diffusion cell method， and the enhancement effect of electroporation was further evaluated by in vivo study in mice. Result:Under steady-state condition， the permeation rates of SNH in stripped skin and intact skin of hairless mice were （385.81±12.88）， （0.88±0.20） μg·cm^-2·h^-1， respectively. The permeation rate in stripped skin was 438 times higher than that in intact skin. The results of percutaneous permeation kinetics analysis showed that the solubility and diffusion coefficient of SNH in stratum corneum were relatively low， which were （70.82±9.63）×10³ g·m^-3 and （3.07±1.52）×10^-14 cm²·s^-1， respectively. Under the optimized electroporation conditions （voltage of 72 V， time of 60 min）， the 24 h cumulative permeation amount of SNH through skin of mice was （10 008.39±1 961.57） μg·cm^-2， and the steady-state permeation rate was （456.01±51.26） μg·cm^-2·h^-1， which were 5.4 times and 5.1 times higher than those of blank group， respectively. In vivo studies in mice showed that the contents of SNH in skin and muscle of electroporation group were 2.0 times and 1.5 times higher than those of blank group. Conclusion:The low solubility and low diffusion coefficient of SNH in the stratum corneum are the main factors hindering the percutaneous permeation of SNH. Electroporation can significantly increase the percutaneous permeation of SNH and its retention in skin and muscle of mice.

Objective:To investigate the clinical characteristics of choledocholithiasis com-bined with periampullary diverticulum and influencing factor for difficult cannulation of endoscopic retrograde cholangiopancreatography (ERCP).Methods:The retrospective case-control study was conducted. The clinical data of 1 920 patients who underwent ERCP for choledocholithiasis in 15 medical centers, including the First Hospital of Lanzhou University, et al, from July 2015 to December 2017 were collected. There were 915 males and 1 005 females, aged (63±16)years. Of 1 920 patients, there were 228 cases with periampullary diverticulum and 1 692 cases without periampullary diverticulum. Observation indicators: (1) clinical characteristics of patients with choledocholithiasis; (2) intraoperative and postoperative situations of patients undergoing ERCP for choledocholithiasis; (3) influencing factor analysis for difficult cannulation in patients undergoing ERCP for choledocholithiasis. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M(range) or M( Q1, Q3), and com-parison between groups was conducted using the Wilcoxon rank sum test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test or Fisher exact probability. The Logistic regression model was used for univariate and multivariate analyses. Results:(1) Clinical characteristics of patients with choledocholithiasis. Age, body mass index, cases with complications as chronic obstructive pulmonary disease, diameter of common bile duct, cases with diameter of common bile duct as <8 mm, 8?12 mm, >12 mm, diameter of stone, cases with number of stones as single and multiple were (69±12)years, (23.3±3.0)kg/m 2, 16, (14±4)mm, 11, 95, 122, (12±4)mm, 89, 139 in patients with choledocholithiasis combined with periampullary diverticulum, versus (62±16)years, (23.8±2.8)kg/m 2, 67, (12±4)mm, 159, 892, 641, (10±4)mm, 817, 875 in patients with choledocholithiasis not combined with periampullary diver-ticulum, showing significant differences in the above indicators between the two groups ( t=?7.55, 2.45, χ2=4.54, t=?4.92, Z=4.66, t=?7.31, χ2=6.90, P<0.05). (2) Intraoperative and postoperative situations of patients undergoing ERCP for choledocholithiasis. The balloon expansion diameter, cases with intraoperative bleeding, cases with hemorrhage management of submucosal injection, hemostatic clip, spray hemostasis, electrocoagulation hemostasis and other treatment, cases with endoscopic plastic stent placement, cases with endoscopic nasal bile duct drainage, cases with mechanical lithotripsy, cases with stone complete clearing, cases with difficult cannulation, cases with delayed intubation, cases undergoing >5 times of cannulation attempts, cannulation time, X-ray exposure time, operation time were 10.0(range, 8.5?12.0)mm, 56, 6, 5, 43, 1, 1, 52, 177, 67, 201, 74, 38, 74, (7.4±3.1)minutes, (6±3)minutes, (46±19)minutes in patients with choledocholithiasis combined with periampullary diverticulum, versus 9.0(range, 8.0?11.0)mm, 243, 35, 14, 109, 73, 12, 230, 1 457, 167, 1 565, 395, 171, 395, (6.6±2.9)minutes, (6±5)minutes, (41±17)minutes in patients with choledocholithiasis not combined with periampullary diverticulum, showing significant differences in the above indicators between the two groups ( Z=6.31, χ2=15.90, 26.02, 13.61, 11.40, 71.51, 5.12, 9.04, 8.92, 9.04, t=?3.89, 2.67, ?3.61, P<0.05). (3) Influencing factor analysis for difficult cannulation in patients undergoing ERCP for choledocholithiasis. Results of multivariate analysis showed total bilirubin >30 umol/L, number of stones >1, combined with periampullary diverticulum were indepen-dent risk factors for difficult cannulation in patients with periampullary diverticulum who underwent ERCP for choledocholithiasis ( odds ratio=1.31, 1.48, 1.44, 95% confidence interval as 1.06?1.61, 1.20?1.84, 1.06?1.95, P<0.05). Results of further analysis showed that, of 1 920 patients undergoing ERCP for choledocholithiasis, the incidence of postoperative pancreatitis was 17.271%(81/469) and 8.132%(118/1 451) in the 469 cases with difficult cannulation and 1 451 cases without difficult cannula-tion, respectively, showing a significant difference between them ( χ2=31.86, P<0.05). In the 1 692 patients with choledocholithiasis not combined with periampullary diverticulum, the incidence of postopera-tive pancreatitis was 17.722%(70/395) and 8.250%(107/1 297) in 395 cases with difficult cannula-tion and 1 297 cases without difficult cannulation, respectively, showing a significant difference between them ( χ2=29.00, P<0.05). In the 228 patients with choledocholithiasis combined with peri-ampullary diverticulum, the incidence of postoperative pancreatitis was 14.865%(11/74) and 7.143%(11/154) in 74 cases with difficult cannulation and 154 cases without difficult cannulation, respectively, showing no significant difference between them ( χ2=3.42, P>0.05). Conclusions:Compared with patients with choledocholithiasis not combined with periampullary divertioulum, periampullary divertioulum often occurs in choledocholithiasis patients of elderly and low body mass index. The proportion of chronic obstructive pulmonary disease is high in choledocholithiasis patients with periampullary diverticulum, and the diameter of stone is large, the number of stone is more in these patients. Combined with periampullary diverticulum will increase the difficult of cannulation and the ratio of patient with mechanical lithotripsy, and reduce the ratio of patient with stone complete clearing without increasing postoperative complications of choledocholithiasis patients undergoing ERCP. Total bilirubin >30 μmol/L, number of stones >1, combined with periampullary diverticulum are independent risk factors for difficult cannulation in patients of periampullary diverticulum who underwent ERCP for choledocholithiasis.

【Objective】 To explore the status quo and influencing factors of knowledge, attitude and practice of voluntary blood donation among undergraduates in Beijing. 【Methods】 A questionnaire was designed on the basis of literature, using the method of convenience sampling to survey the undergraduates from 39 universities in Beijing. The t-test, analysis of variance and χ² test were used to compare the differences in knowledge, attitude and practice of voluntary blood donation among different groups, and logistic regression model was performed to analyze the influencing factors. 【Results】 A total of 1 075 valid questionnaires were collected from undergraduates of 39 universities in Beijing. The results showed that the proportion of the participants who had good knowledge about voluntary blood donation was 69.21% (744/1 075). No statistically significant difference was noticed on the scores of voluntary blood donation knowledge between males and females (P>0.05). The scores of voluntary blood donation knowledge of medical students were higher than those of other subjects (P<0.05). The scores of voluntary blood donation knowledge of juniors and above were higher than those of lower grades (P<0.05). The rate of undergraduates participating voluntary blood donation in Beijing was 30.98% (333/1 075). A total of 67.26% (723/1 075) of students had donation intention, 9.49% (102/1 075) didn’t and 23.25% (250/1 075) were not sure. No statistically significant differences in blood donation intention were observed among undergraduates by genders and grades (P>0.05). The rate of medical students’ intention to donate blood was higher than that of other subjects (P<0.05). 【Conclusion】 The rate of voluntary blood donation among undergraduates in Beijing was above the middle level compared with other regions in China, but the practice of voluntary blood donation is far away from the intention. Therefore, it’s necessary to improve the level of knowledge, attitude and practice of undergraduates, especially non-medical college students, so as to improve the rate of voluntary blood donation among the undergraduates in Beijing.

Background::Although overnight fasting is recommended prior to endoscopic retrograde cholangiopancreatography (ERCP), the benefits and safety of high-carbohydrate fluid diet (CFD) intake 2 h before ERCP remain unclear. This study aimed to analyze whether high-CFD intake 2 h before ERCP can be safe and accelerate patients’ recovery.Methods::This prospective, multicenter, randomized controlled trial involved 15 tertiary ERCP centers. A total of 1330 patients were randomized into CFD group ( n = 665) and fasting group ( n = 665). The CFD group received 400 mL of maltodextrin orally 2 h before ERCP, while the control group abstained from food/water overnight (>6 h) before ERCP. All ERCP procedures were performed using deep sedation with intravenous propofol. The investigators were blinded but not the patients. The primary outcomes included postoperative fatigue and abdominal pain score, and the secondary outcomes included complications and changes in metabolic indicators. The outcomes were analyzed according to a modified intention-to-treat principle. Results::The post-ERCP fatigue scores were significantly lower at 4 h (4.1 ± 2.6 vs. 4.8 ± 2.8, t = 4.23, P <0.001) and 20 h (2.4 ± 2.1 vs. 3.4 ± 2.4, t= 7.94, P <0.001) in the CFD group, with least-squares mean differences of 0.48 (95% confidence interval [CI]: 0.26–0.71, P <0.001) and 0.76 (95% CI: 0.57–0.95, P <0.001), respectively. The 4-h pain scores (2.1 ± 1.7 vs. 2.2 ± 1.7, t = 2.60, P = 0.009, with a least-squares mean difference of 0.21 [95% CI: 0.05–0.37]) and positive urine ketone levels (7.7% [39/509] vs. 15.4% [82/533], χ2 = 15.13, P <0.001) were lower in the CFD group. The CFD group had significantly less cholangitis (2.1% [13/634] vs. 4.0% [26/658], χ2 = 3.99, P = 0.046) but not pancreatitis (5.5% [35/634] vs. 6.5% [43/658], χ2 = 0.59, P = 0.444). Subgroup analysis revealed that CFD reduced the incidence of complications in patients with native papilla (odds ratio [OR]: 0.61, 95% CI: 0.39–0.95, P = 0.028) in the multivariable models. Conclusion::Ingesting 400 mL of CFD 2 h before ERCP is safe, with a reduction in post-ERCP fatigue, abdominal pain, and cholangitis during recovery.Trail Registration::ClinicalTrials.gov, No. NCT03075280.