1.Effects of potassium concentration and ion channel conductance on spontaneous firing of Hippocampal CA1 neuron
International Journal of Biomedical Engineering 2011;34(2):86-90
Objective To analyse the variability of spontaneous firing frequencies and firing patterns of a Hippocampal CA1 neuron with the changes of extracellular potassium concentration[K+]0 and ion channel conductance.Methods A 16-compartment cable model of a Hippocampal CA1 neuron was developed based on the Warman model with computer software MATLAB.The dendrites contained no active channels,while five active channels (INa,INap,IDR,IA,IM)were contained in soma.In the model,the calcium currents and potassium currents(ICm,,ICT and IAHP) regulated by calcium concentration were not included.ResultsSimulation results showed that the neuron could generate periodicspontaneous firing activity.The spiking frequency increased with the increasing of[K+]0 and sodium conductance and decreasing of potassium conductance.Spontaneous single neuron activity appeared in singlet or in grouped bursts of two or three spikes.Conclusion The variability of spontaneous firing frequencies and firing patterns of single neuron are relevant to[K+]0 and ion channel conductance.
2.Simulation of extracellular electrical stimulation of rat optic nerve fiber based on experimental data
Jie GAO ; Qingli QIAO ; Nan XIE
Chinese Journal of Tissue Engineering Research 2010;14(9):1629-1633
BACKGROUND:Currently,there are three types of visual prosthesis:retinal prosthesis,optic nerve prosthesis and visual cortical prosthesis.Normal optic nerve fiber is the basis to apply visual prosthesis.Extracellular stimulation of myelinated optic nerve fiber is developed from intracellular stimulation,with feasible selection of stimulation locations and low requirements for operation.OBJECTIVE: Using computer to simulate the response of myelinated rat optic nerve fiber to extracellular point current source and to analyze the effect of the position of the point source on the response of the optic nerve fiber.METHODS:The experiment data of ion channels of rat optic nerve fiber and the characteristic of common ion channels were summarized,and the existing Hodgkin-Huxley like optic nerve fiber models were analyzed.The response of the optic nerve fiber model was simulated by computer,and the differences of action potentials of Ranvier node were compared by changing the position of point source.RESULTS AND CONCLUSION:Simulated models showed that the response of optic nerve is affected by the position of extracellular exciting electrode.The myelinated rat optic nerve fiber is easier to activate when the distance between point source and the Ranvier node center of the optic nerve fiber is short.
4.The research progress of equations for estimated glomerular filtration rate in diabetic patients and the elderlys
Danshu XIE ; Hao SHI ; Nan CHEN
Chinese Journal of Endocrinology and Metabolism 2016;32(12):1036-1040
The evaluation of glomerular filtration rate is important in the diagnosis,treatment, and prognosis for patients. Although there are different equations widely used and convenient,the accuracy of them on the specific populations, including diabetic patients and the elderlys, still needs further discussion. We recommend using the Chronic Kidney Disease Epidemiology Collaboration ( CKD-EPI) from creatinine and cystatin C in the elderlys. For diabetic patients, however, this equation should be recommended with cautions.
5.The status quo investigation of nurses′cognitive and attitude of adverse event reporting
Suying FENG ; Nan XIE ; Yuxia YANG
Chongqing Medicine 2015;(5):687-689
Objective To calculate the probability of nurses in a city experiencing adverse event and investigate nurses′cognitive and attitude of adverse event reporting ,and to improve the adverse event reporting system for care .Methods Three hundred and seventy five nurses were selected from 15 hospitals in our city and investigated by questionnaire survey .Results There were not statistically significant difference in the probability of nurses experiencing adverse event among all the different levels hospitals (P>0 .05) .There were statistically significant difference among three factors influencing the probability of nurses experiencing adverse event ,including professional title ,different age ,length of service(P<0 .05) .There were statistically significant difference of actively reporting the adverse event among nurses with different length of service (P<0 .05) .Conclusion Nurses′cognitive and attitude to‐wards adverse events report is positive .The length of service ,punishment environment and management expectation are the factors influencing the executive intention of adverse events .Investigating safety problems from the systematic perspective and improving adverse events reporting system could get more information and synthetically analyze the information to avoid nursing risk events e‐ventually .
6.Evaluation on Transverse Process Fractures of the Lumbar Spine
Journal of Practical Radiology 2000;0(02):-
Objective To evaluate the relationship between transverse process fractures of lumbar spine and blunt abdominal trauma.Methods 169 cases of blunt abdominal trauma were reviewed.Number and type of lumbar transverse process fractures associated intra-abdominal injuries were recorded.Results 148 fractures in 81 cases showed transverse process fractures on CT (single fractures in 43,multiple fractures in 38).Of them,the fractures were at right-sided in 28 patients,left-sided in 33 and bilateral in 20.Transverse process fractures of L 1 vertebra were most common(n=60).Transverse process fractures were associated with abdominal trauma in 15 cases (18%), both was statistically significant (?
7.Retrospective study on the changes of refractive state and stability after cataract surgery
International Eye Science 2016;16(10):1865-1868
AIM: To compare and contrast different operation after cataract patients with refractive change rules. To analyze the patients with refractive stability after cataract surgery, and to provide a reference for cataract patients with clinical surgery after visual quality.
●METHODS: Retrospective study. A total of 126 cases (150 eyes) were selected from Jan. 2014 to Dec. 2015 in Changzhou First People′s Hospital of cataract extraction combined with foldable intraocular lens implantation for cataract patients as the research samples. According to the different operation for three groups, the first group of 42 patients ( 50 eyes ) underwent above 3 mm clear corneal incision;52 cases in group 2 (60 eyes) underwent temporal side 3 mm clear corneal incision. The third group, 32 cases (40 eyes) underwent 3 corner above the scleral tunnel incision. All the cases were measured at different time point in patients with naked eyes far visual acuity, best corrected visual acuity, spherical degree, the degree of astigmatism and astigmatic axial, comparative analysis of after cataract surgery in patients with refractive change regularity and stability of refraction.
●RESULTS: The uncorrected distance visual comparison within the group, and each time point after preoperative differences were significant ( P< 0. 01 ), and the early postoperative period after 1, 3mo significantly different (P<0. 05). Three groups of patients after surgery compared with preoperative uncorrected distance visual acuity improved significantly, and were stable after 1mo. Compare the best corrected distance vision within the group, and each time point after preoperative differences were significant (P<0. 01), postoperative 1wk and after 1, 3d significantly different (P<0. 05), after 1wk and after 1, 3mo was not significantly different ( P > 0. 05 ), three groups of patients were compared with the preoperative best corrected distance visual acuity were increased significantly, and were in stable after 1wk; relatively spherical degree within the array, after 1d and 3d was not significantly different (P>0. 05), hyperopia drift, after 1wk and 1, 3d was significantly different (P<0. 05), after 1wk and 1, 3mo was not significantly different ( P>0. 05 ). Three groups of patients′spherical degrees after 1wk were stabilized. Comparative degree of astigmatism within the array, postoperative compared with preoperative corneal astigmatism were increased 1d after surgery. Corneal astigmatism in each group reached the maximum, and then decreases 1wk and 1d after surgery, compared with postoperative 3d was significantly different ( P<0. 05 ). After 1wk and 1, 3mo was not significantly different ( P>0. 05 ) . Three groups of patients were compared with preoperative astigmatism were significantly increased, and in operation after 1wk were stabilized;astigmatic axis were three groups in the preoperative astigmatism against the rule, the first and third group after 1d, three Tianshun rule astigmatism proportional were increased, and then decreased. Group 2 the- rule astigmatism proportion, after 1wk, 1 and 3mo, the first and third group gradually reduced the proportion of cis regulatory astigmatism, and compared with preoperative increased, increasing the-rule astigmatism group 2 ratio, and increased compared with preoperative.
●CONCLUSION: Above 3 mm the transparent corneal incision, temporal clear corneal incision and above the scleral tunnel incision different surgical postoperative visual acuity are good. lt can be used as a routine surgical procedure in treatment of cataract;phacoemulsification in cataract patients with former majority against the rule astigmatism. After cataract surgery, early refractive state is a state of mild hyperopia and stabilized about 1wk, combined with clinical guide glasses.
8.THE HEART STRUCTURE AND FUNCTION CHANGES AND RELATED RISK FACTORS OF TYPE 2 DIABETIC PATIENTS
Guonan DENG ; Peizhou GAN ; Xia′nan XIE
Modern Hospital 2014;(8):27-29
Objective To investigate the changes of cardiac structure and function in type 2 diabetes mellitus (T2DM), analyze the related risk factors of heart failure, and improve the awareness of the effect of diabetes on the heart. Methods Randomly selected 170 cases of T2DM patients As the object of study, 170 cases of non diabetic patients as con-trol group, according to whether complicated with heart failure were divided into heart failure patients and non heart failure patients.Comparison of each group left ventricular posterior wall thickness, left ventricular end diastolic diameter, left ven-tricular end systolic diameter, left ventricular ejection fraction, E/A ratio Differences, analysis of the related risk factors of heart failure by logistic regressive.Results T2DM group left ventricular posterior wall thickness, left ventricular end diastolic diameter and left ventricular end systolic diameter increased , Left ventricular ejection fraction decreased, E/A ratio de-creased, were statistically significant difference compared with the control group (p <0.05).These differences are mainly come from non heart failure patients.Logistic regression showed that factors in patients with diabetes duration, HbA1c, com-pliance and complications of hypertension, coronary heart disease, is a risk factor for heart failure complicated with T2DM (all p<0.01).These may be the risk factor for diabetic patients with heart failure.Conclusion Diabetes can cause cardiac remodeling, systolic and diastolic dysfunction maybe some T2DM patients.They did not show symptoms of heart failure in the clinical, but their Cardiac structure and function are abnormal.We should pay attention to the cardiac function examination and early evaluation, prevention of risk factors, to avoid the occurrence of heart failure.
9.Effect of dexmedetomidine on liver injury in rats with obstructive jaundice
Yi′nan LIANG ; Yaying XIE ; Jianshe YU ;
Chinese Journal of Anesthesiology 2016;36(9):1072-1075
Objective To evaluate the effect of dexmedetomidine on liver injury in the rats with ob?structive jaundice. Methods Forty?five healthy male Sprague Dawley rats, weighing 250-300 g, aged 8-9 weeks, were divided into 3 groups ( n=15 each) using a random number table: sham operation group ( S group) , obstructive jaundice group ( OJ group) and dexmedetomidine group ( D group) . Obstructive jaun?dice was induced in rats by division and double ligation of the common bile duct in OJ and D groups. Dexmedetomidine 100 μg∕kg was injected intraperitoneally at 72 h after establishment of the model in group D. At 3, 5 and 24 h after administration, blood samples were collected from hearts for determination of the plasma alanine aminotransferase (ALT) and C?reactive protein (CRP) levels. After blood sampling at each time point, the specimens from the external right lobe of the liver were obtained for detection of the expres?sion of Toll?like receptor 4 ( TLR4) mRNA ( by real?time polymerase chain reaction) and TLR4 content ( by enzyme?linked immunosorbent assay) in liver tissues and for pathological examination of liver tissues ( with light microscope) . Results Compared with group S, the plasma ALT and CRP levels were significantly increased at each time point after administration, and the expression of TLR4 mRNA in liver tissues was significantly up?regulated, and TLR4 content in liver tissues was significantly increased in OJ and D groups ( P<0?05) . Compared with group OJ, the plasma ALT and CRP levels were significantly decreased at each time point after administration, and the expression of TLR4 mRNA in liver tissues was significantly down?regulated, and TLR4 content in liver tissues was significantly decreased in group D ( P<0?05) . The degree of damage to liver tissues was significantly attenuated in group D compared with group OJ, and was aggrava?ted in group D compared with group S. Conclusion Dexmedetomidine can reduce liver injury in the rats with obstructive jaundice.
10.Effect of ethanolic extract of Omithogalum caudatum Ait on apoptosis of Candida albicans
Nan WANG ; Meizhu MENG ; Kunpeng XIE ; Mingjie XIE
Chinese Journal of Biochemical Pharmaceutics 2017;37(4):9-11
Objective To investigate the effect of Omithogalum caudatum Ait(OCA)on apoptosis of Candida albicans,illustrated the antifungal mechanism of OCA.Methods Annexin Ⅴ-FITC/PI double stainingwas used to detect the effect of OCA on the apoptosis of C.albicans;JC-1 and DCFH-DA staining were used to detectthe effect of OCA on mitochondrial membrane potential(MTP)and reactive oxygen species(ROS)of C.albicans.Results OCA had a good antifungal activity,the minimum inhibitory concentration(MIC)and the minimum fungicidal concentration(MFC)were 8mg/mL and 32mg/mL respectively.OCA could induceapoptosis of C.albicans,promote the reduction of MTP and increase of ROS.Conclusion OCA induced cell apoptosismainly through disrupting mitochondrial function.