1.Simulation of intestinal content sensory nerves with ultrasonic detection system
Jianguo LI ; Chengxian TANG ; Xuefeng YANG ; Xianhui SHANG ; Jiaping CHENG
Chinese Journal of Tissue Engineering Research 2013;(37):6601-6606
BACKGROUND:The existed artificial anal sphincter cannot sense whether there are intestinal contents in the bowel and the state of intestinal contents, and the previous studies on the intestinal content signal did not included the different parts of colon and the signals of different intestinal content status.
OBJECTIVE:To compare the differences of ultrasound signals of different intestinal content status in different parts of New Zealand rabbits detected with transmission-type ultrasonic signal detection system.
METHODS:Twenty healthy New Zealand rabbits were used;the rabbits were divided into groups according to distal part of proximal colon, distal colon and distal rectum. Five positions of solid stool particles were selected randomly as the detection point in each group. The voltage signals of stool were measured under solid, fluid, gaseous, and deflation status of the lumen.
RESULTS AND CONCLUSION:In rectum, there were no significant differences in voltage signals between solid and gaseous conditions, while there were significant differences between fluid and deflation conditions (P=0.000). Multiple comparison showed there were significant differences between four conditions in distal part of proximal colon and distal colon (P=0). There were significant differences in voltage singles between rectum, distal colon and proximal colon under solid and fluid conditions (P=0). Multiple comparison showed there were significant differences in any part of large bowel for solid and fluid status (P=0). There were no significant differences in voltage singles between rectum, distal colon and proximal colon under gaseous and deflation conditions. There was interactive effect of intestinal contents between three parts of large bowel under the four conditions (P=0.000). Transmission-type ultrasonic detection system can distinguish artificial intestinal contents sensory nerves of various intestinal contents. And the application of ultrasonic detection system to detect the intestinal contents under different conditions can provide a new effective method for the research on artificial intestinal content sensory nerves.
2.Median effective concentration of amitripthline for intravenous regional anesthesia in rats
Xianhui KANG ; Li SONG ; Yunfei CHAI ; Bangxiang YANG ; Fan YANG ; Guanwangning SHANG ; Hui LIU
Chinese Journal of Anesthesiology 2008;28(7):626-629
Objective To determine the median effective concentration (EC50) of amitriptyline for intravenous regional anesthesia (IVRA) in rats.Methods Ninety healthy male SD rata weighing 190-240 g were randomly divided into 3 groups (n=30 each) : amitripryline group,bupivncaine group and lidocaine group.The rat's tail was divided into 3 epual parts: the proximal,middle and distal part.A 24 gauge needle was inserted into vena caudalis in the distal part.Esmarch bandage was applied around the tail from distal to proximal to expel blood from the taft and was removed after a tourniquet was applied between the proximal and middle part of the tail to occlude artery.0.5 ml of amitriptyline,bupivncaine or lidocaine was injected into the taft vein immediately after the application of the tourniquet.Ten minutes after drug administration the tourniquet was released.The ECho was determined by the up-and-down sequence method.The initial concentration of amitriptyline was 0.05%,the consecutive concentration-ratio was 1.4i4; the initial concentration of bupivacaine was 0.03%,the consecutive concoatration-ratio was 1.667 and the initial concentration of lidncaine was 0.08%,the consecutive concentrationratio was 1.250.EC50 and 95% confidence interval were calculated.Tail-flick latency (TFL) was assessed at 1 h before (baseline) and at 3 min and 2 d after drug administration.Central nervous system toxicity (seizure,convulsion,death) and local tissue damage to the tail were also recorded.Results The EC50 for IVRA was 0.111% (95% CI,0.092%-0.133%) in amitripthline group; 0.058% (95% CI,0.048%-0.078%) in bupivacaine group and 0.129% (95% CI,0.103%-0.160%) in lidocaine group respectively.The EC50 was significantly lower in bupivacaine group than in amitriptyline and lidocaine group.There was no significant difference in EC50 between amitriptyline and lidocaine group.The TFL measured at the proximal part of the tail was not significantly different between different time points in each group.The TFL measured at the middle part at 3 rain after drug adminisuation was significantly increased as compared with the baseline in all 3 groups but was not significantly different between the baseline and that measured at 2 d after drug administration.No CNS toxicity and local tissue damage were found during the experiment in all 3 groups.Conclusion Amitriptyline can produce intravenous regional anesthesia.The potency of amitriptyline is significantly lower than that of bupivncaine but is not significantly different from that of lidocaine.
3.A study on the classification of intestinal contents based on miniature reflection ultrasound.
Jianguo LI ; Xiaoxiang LIANG ; Xianhui SHANG ; Xingbin ZHENG
Journal of Biomedical Engineering 2018;35(1):60-63
The present artificial anal sphincter fails to distinguish the different states of intestinal contents. In this study, we tried to distinguish the intestinal content by using a reflection type ultrasonic system, so as to lay the foundation for the development of artificial anal sphincter with sensing function. We measured the numbers of reflected waves when there were solid, liquid, gaseous or no contents in the recta of 30 Bama Miniature pigs. The results showed significant difference among the numbers of reflected waves of the 4 conditions ( = 1 088, < 0.05). Our research suggested the reflection-type ultrasonic system could be utilized to distinguish various contents inside the intestinal lumen, thus it might offer a new effective method for the development of artificial anal sphincter with sensing function.
4.The association between carotid atherosclerosis and ischemic stroke in patients with nonvalvular atrial fibrillation
Luxiang SHANG ; Mengjiao SHAO ; Yang ZHAO ; Min FENG ; Huaxin SUN ; Xiaokereti JIASUOER· ; Kui LIANG ; Zhenyu DONG ; Xianhui ZHOU ; Baopeng TANG
Chinese Journal of Internal Medicine 2020;59(4):292-296
Objective:To investigate the relationship between indicators of carotid atherosclerosis and onset of ischemic stroke in patients with non-valvular atrial fibrillation (NVAF).Methods:This is a case-control study, a total of 397 NVAF patients with newly diagnosed ischemic stroke (case group) and 3 038 NVAF patients without ischemic stroke (control group) from January 2015 to December 2017 were included in the study. Differences in general clinical features and carotid atherosclerosis indexes between the two groups were compared. Univariate and multivariate logistic regressions were used to analyze the correlation between carotid atherosclerosis indexes and ischemic stroke.Results:Proportions of patients with carotid intima thickening, carotid plaque, stable plaque, unstable plaque, and moderate to severe stenosis were higher in the ischemic stroke group than those in the control group (82.1% vs. 64.4%, 69.3% vs. 50.3%, 43.6% vs. 30.6%, 25.7% vs. 19.7%, and 7.3% vs. 4.0%, respectively, all P <0.05). After adjustment of age, gender, heart failure, hypertension, low density lipoprotein -cholesterol and drug use, multivariate analyses showed that subjects with carotid intima thickening, carotid plaque, stable plaque, unstable plaque, moderate to severe stenosis had 1.766, 2.111, 1.892, 2.256 and 1.824 times the risk for the development of ischemic stroke compared with the subjects without any carotid atherosclerosis indicators. Conclusion:Carotid atherosclerosis, especially with unstable carotid plaque, is associated with ischemic stroke in patients with NVAF.