1.Pharmacokinetic behavior of 16-dehydropregnenolone after intramuscular administration in rats
Hongying YANG ; Wenmeng ZHANG ; Wenwen YANG ; Ting ZHAO ; Lixin SUN
Journal of Pharmaceutical Analysis 2011;01(2):135-138
The pharmacokinetics of 16-dehydropregnenolone (16-DHP),a sterols compound isolated from Solanum lyratum Thunb.,was investigated in rats following a single intramuscular administration (40 mg/kg).The concentration of 16-DHP in rat plasma was determined by a high performance liquid chromatography (HPLC) method with UV detection.Levonorgestrel was used as the internal standard (IS).The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method.After a single intramuscular administration,the maximum plasma concentration (Cmax,) was (289 ±25)ng/mL,time to reach Cmax(tmax) was (0.38±0.14) h,the elimination half-life (t1/2) was (2.5±1.1)h,the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUC10-t)) was (544 ± 73 )ng· h/mL.The results indicated that 16-DHP was alsorbed quickly and eliminated rapidly in rats after the intramuscular injection.
2.Cyclic fatigue performance of different types of stainless steel root canal files
Xin HU ; Lei WANG ; Qian ZHANG ; Jia NING ; Wenmeng WU
Chinese Journal of Tissue Engineering Research 2017;21(26):4125-4130
BACKGROUND: Root canal files fracture is a kind of common oral clinical complications. Therefore, it is of clinical importance to study the cyclic fatigue of different types of stainless steel root canal files.OBJECTIVE: To explore the effect of the bending angle and cross-sectional area of root canal instruments on cyclic fatigue of stainless steel files.METHODS: Thirty 25# stainless steel K files (25 mm in length) were selected, the same to 30# and 35#. And these three kinds of files were respectively randomized into three groups (n=10 per subgroup). In the nine subgroups, the files were placed into self-made root canals at the bending angle of 45°, 60°, 90°, and driven by a 16:1 reducer (350 r/min).Fracture time in each subgroup was recorded and converted into the number of rotations. The microstructure of the fracture end of the files was observed under scanning electron microscope. Fractured files were collected and the crack tip length was measured by an electronic caliper.RESULTS AND CONCLUSION: At the same bending angle, the number of rotations resulting in file fracture was significantly reduced with the increasing of the cross-sectional area of the files (P < 0.05). When the type and cross-sectional area were same, the number of rotations resulting in file fracture was significantly reduced with the increasing of the bending angle of the root canals (P < 0.05), indicating a reduction in the cyclic fatigue performance of the files. Toughness fracture occurred in all the files, and circular or oval roughness nests with different sizes and microcavities formed on the fracture surface. In addition, brittle surfaces could be detective between the roughness nests. The diameter of roughness nests was gradually increased with the increasing of the bending angle of the root canals. For 30# and 35# files, the number of brittle surfaces was gradually increased with the increasing of the bending angle of the root canals. For 25# files, the crack tip length was gradually decreased with the increasing of the bending angle of the root canals, but there was no significant difference (P > 0.05). For 30# and 35# files, the crack tip length was significantly shortened with the increasing of the bending angle of the root canals (P < 0.05). But there were no significant changes in the 35#-60° and 35#-90° groups (P=0.095). At the same bending angle, there were no regular changes in the crack tip length in the different types of files. In conclusion, with the increasing of the cross-sectional area, the cyclic fatigue performance of the files with the same length and taper is reduced and the files become easy to be fractured; with the increasing of the bending angle of the root canals, the files with the same types are apt to be fractured near the root tip, indicating the shorter length of the crack tip indicates the more difficulty in the removal of the broken files.
3.RP-HPLC method for the simultaneous determination of daidzein,genistein and formonetin in Solanum Lyratum Thunb
Yurong JIA ; Wenmeng ZHANG ; Ting ZHAO ; Wenwen YANG ; Lixin SUN
Journal of Pharmaceutical Analysis 2010;22(3):156-159
A rapid method for the simultaneous determination of daidzein, genistein and formonetin in solanum Lyratum Thunb by high performance liquid chromatography (HPLC) was developed. Separation was achieved on a Diamonsil C18 column (250 mm×4.6 mm, 5 μm) with isocratic elution, using a mobile phase of methanol-tetrahydrofuran-water (44∶3∶53, v/v). The wavelength was set at 260 nm and column was maintained at 35 ℃. The linear ranges of daidzein, genistein and formonetin were 1.0-40.0, 0.1-4.0 and 0.1-4.0 μg/mL, respectively. The average recoveries were between 98.4% and 101.3%. This method could be used for the quality control of Solanum lyratum Thunb due to its simplification, reliability, rapidity and excellent precision.
4.Pharmacokinetic behavior of 16-dehydropregnenolone after intramuscular administration in rats
Hongying YANG ; Wenmeng ZHANG ; Wenwen YANG ; Ting ZHAO ; Lixin SUN
Journal of Pharmaceutical Analysis 2011;01(2):135-138
The pharmacokinetics of 16-dehydropregnenolone (16-DHP), a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a single intramuscular administration (40 mg/kg). The concentration of 16-DHP in rat plasma was determined by a high performance liquid chromatography (HPLC) method with UV detection. Levonorgestrel was used as the internal standard (IS). The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method. After a single intramuscular administration, the maximum plasma concentration (Cmax) was (289±25)ng/mL, time to reach Cmax(tmax) was (0.38±0.14) h, the elimination half-life (t1/z) was (2.5±1.1)h, the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUC(0-t)) was (544± 73)ng· h/mL. The results indicated that 16-DHP was absorbed quickly and eliminated rapidly in rats after the intramuscular injection.
5.Clinical and pathological evaluation of conservative surgery for tubal pregnancy
Qian XIE ; Wenmeng LUO ; Ling LING ; Qin YIN ; Yu ZHANG
Chongqing Medicine 2014;(26):3416-3417,3421
Objective To conduct the clinical and pathological evaluation on the conservative surgery in tubal pregnancy . Methods 513 cases of tubal pregnancy in this hospital from January 2006 to December 2012 were divide into the conservative sur-gery group(A ,314 cases) ,samlpintectomy group(B ,43 cases) and the medication conservative treatment group (C ,156 cases) .The hospitalization days ,HCG negative-conversion time ,cure rate ,re-pregnancy outcome ,pregnancy during 1-year follow-up were com-pared between the group A and C .In group B ,43 cases of tubal pregnancy and accomplishing fertility were firstly performed the tubal linear incision in the pregnant site ,then the biopsy was conducted after stopping bleeding and finally the salpingectomy in af-fected side was performed .The tubal electric injury degree by the unipolar or bipolar electrocoagulation and the pathological changes under light microscope were observed .Results The hospitalization days ,symptom relief rate ,HCG negative-conversion time ,cure rate and re-pregnancy outcome had statistical differences between the group A and C (P<0 .05) .Conclusion The tubal conserva-tive surgery has short hospitalization time ,high symptom relief rate ,high cure rate and few complications .The pathological observa-tion shows the localized electrocoagulation injury .The pregnancy rate after surgery is high .
6.Simultaneous determination of five nucleosides and nucleobases of Rehmannia glutinosa Libosch. by high performance liquid chromatography.
Wenmeng ZHANG ; Wenwei FU ; Mingyu SUN ; Lixin SUN ; Yurong JIA ; Ping LIU
Acta Pharmaceutica Sinica 2011;46(11):1380-4
This study is to establish a method for simultaneously determination of five nucleosides and nucleobases, including hypoxanthine, uridine, adenine, guanosine and adenosine in Rehmannia glutinosa Libosch. which was collected from different regions in China. A Diamonsil C18 column (250 mm x 4.6 mm, 5 microm) was used. Acetonitrile and 0.04 mol L(-1) potassium dihydrogen phosphate solution were adopted as mobile phase with gradient elution. The flow rate was 1 mL min(-1) and column temperature was 30 degrees C. The detection wavelength was at 254 nm. The method had good linearity over the range of 1.0 - 16.0 microg mL(-1) (r2 = 0.999 8), 5.0 - 80.0 microg mL(-1) (r2 = 0.999 8), 1.0 - 16.0 microg mL(-1) (r2 = 0.999 5), 1.25 - 20.0 microg mL(-1) (r2 = 0.999 8) and 1.0 - 16.0 microg mL(-1) (r2 = 0.999 8) for hypoxanthine, uridine, adenine, guanosine and adenosine, respectively. The average recoveries were between 98.8% and 100.7%. The content of hypoxanthine, uridine, adenine, guanosine and adenosine in Rehmannia glutinosa Libosch. from different regions was significantly different. This established method was sensitive and reliable for the quantification of five chemical constituents in Rehmannia glutinosa Libosch.
7.Effects of Chinese herbal medicine Xiaopi Pill in preventing rats from dimethylnitrosamine-induced liver fibrosis.
Xiao ZHANG ; Bingbing NING ; Shuang REN ; Lijun ZHANG ; Wenmeng ZHANG ; Jiamei CHEN ; Gaofeng CHEN ; Hua ZHANG ; Yongping MU ; Ping LIU
Journal of Integrative Medicine 2012;10(11):1286-92
To explore the intervention effects of Xiaopi Pill (XPW), a compound traditional Chinese herbal medicine, on the development progress of dimethylnitrosamine (DMN)-induced liver fibrosis in rats.