1.Discussion of the application of three-point interaction principle to the phenylglycine racemic compound in IR spectrometry and its enantiomers separation in HPLC.
Yi SHEN ; Da-nian YI ; Ji-ning LIU
Acta Pharmaceutica Sinica 2002;37(8):636-638
AIMTo discuss the relationship between the three-point interaction principle in the stereoselective separation of chromatography and applying this principle to survey the infrared spectrometry of racemate.
METHODSIn proving the applicability of the three-point interaction principal in IR spectrometry, a special case was found that phenylglycine did not obtain enantioselective separation on the chiral column but its IR spectrometry still obey this principle and explained such special case by experiment.
RESULTSAfter an equal quantity of solid crystal of d-phenylglycine and l-phenylglycine were mixed and ground for several minutes, they transformed to racemic compound. X-powder diffraction also confirmed this fact.
CONCLUSIONThe three-point principle was relatively reliable when it was used in the enantioselective chromatography separation and the IR spectrometric analysis. The reason of the fact that phenylglycine was not separated by chiral column can be explained by the fact that the acting force between the three polarity groups in the enantiomers is so strong that they can not form the instantaneous diastereoisomer with the chiral column, it was agreeable with the phenomenon that racemic mixture easily became racemic compound only by simply grinding the mixture in IR spectrometric experiment.
Chromatography, High Pressure Liquid ; Glycine ; analogs & derivatives ; analysis ; chemistry ; Orosomucoid ; chemistry ; Spectrophotometry, Infrared ; Stereoisomerism
2.Effects of changes in conformation and configuration of N-containing compounds on NMR spactra.
Dan-yu HUA ; Da-nian YI ; Ji-ning LIU
Acta Pharmaceutica Sinica 2003;38(12):946-949
AIMTo find the cause of abnormal NMR spectra of lomerizine dihydrochloride, cetirizine dihydrochloride and flenfluramine camphoramide.
METHODSHypothesizing, in given conditions, there are changes of stereoisomeric conformation and configuration in structure of N-containing compounds, it results in abnormality of NMR spectra. By using the method of NMR, it is confirmed credibily.
RESULTS AND CONCLUSIONThe moving balance exists between two chair conformations in lomerizine dihydrochloride and cetirizine dihydrochloride. It causes that spin-nuclei of whole molecule are placed in two chemical circumstance. In solution of DMSO-d6, the speed of conformation reversal equals to the NMR time scale, so that chemical shift of spin-nuclei can not be definitely determined, peaks are broadened and even collapsed. After dropping D2O or increasing the temperature, the viscosity of the solution is decreased, the speed of reversal is quicker than NMR time scale, then normal spectra are obtained. Owing to the reversal of the three bonds of nitrogen in flenfluramine camphoramide is limited, other pair of diastereoisomer resulted from the asymmetric nitrogen can be detected by NMR. Multiplication of the peaks of 13CNMR is reasonably explained.
Cetirizine ; chemistry ; Fenfluramine ; chemistry ; Magnetic Resonance Spectroscopy ; Molecular Conformation ; Piperazines ; chemistry
3.Relationship between germ cell apoptosis and Sertoli cell vimentin in prepubertal rats induced by local exposure to heat.
Ji-qiang ZHANG ; Da-nian QIN ; Hai-yan CUI
National Journal of Andrology 2006;12(3):202-206
OBJECTIVETo explore the relationship between germ cell apoptosis and the expression as well as the distribution of Sertoli cell vimentin induced by local exposure to heat.
METHODSLocal short-term exposure of prepubertal male rats testis to heat (43 degrees C for 15 min). Histochemical method was used to observe morphological characteristics of seminiferous tubule. The distribution and expression of Sertoli cell cytoskeletons were analyzed by immunohistochemistry and germ cell apoptosis was evaluated by TUNEL technique at different hour-intervals.
RESULTSAfter 2 h and 4 h heat exposure, the disattachment phenomenon between Sertoli cell and spermatogonia occurred. Spermatogonia arranged in disorder and displaced away from the basement membrane of seminiferous tubules. Immunohistochemical staining showed that vimentin positive staining was seen radiating from the Sertoli cell perinuclear region with apical "spoke-like" pattern in controls. There was an intense vimentin immunoreactivity surrounding Sertoli cell nuclei along with the collapse of the apical extensions in 2 h group, but no significant difference compared with the controls. The expressions of vimentin in 12 h and 24 h groups were higher than those of the controls (P <0.01), respectively. TUNEL showed that incidence of apoptosis was observed to increases markedly in 12 h and 24 h groups, but it was found that the incidences of apoptotic events were decreased in these two groups compared with the controls.
CONCLUSIONThe changes of expression and distribution of Sertoli cell vimentin filaments correlate with the increased germ cell apoptosis. Local heat may disrupt spermatogenesis by injuring Sertoli cell directly.
Animals ; Apoptosis ; Hot Temperature ; In Situ Nick-End Labeling ; Male ; Rats ; Rats, Sprague-Dawley ; Sertoli Cells ; metabolism ; Spermatozoa ; pathology ; Vimentin ; biosynthesis
4.Experimental study on the survival of venous flap with different pedicle styles.
Shan-zhang TAN ; Ji ZHANG ; Hui WANG ; Nian CHEN ; Yan FU ; Da-li ZHANG
Chinese Journal of Plastic Surgery 2006;22(3):196-199
OBJECTIVETo study a new method of venous flap that is improved on its persistence and quality.
METHODSNew Zealand white rabbits were subdivided randomly into 4 groups. All rabbits were operated by harvesting a flap from the latero-abdominal wall and then sutured it in the original position. Group A: the superficial epigastric vein in the pedicle was left open (only one inflow vein remained). Group B: the pedicle vein of the proximal and distant end were left open (keeping an inflow vein and a principal out). Group C: the pedicle vein and a tributary vein were left open (keeping an inflow vein and a tributary outflow vein). Group D: the pedicle vein and two tributary veins were left open (keeping an inflow vein and two tributary outflow veins). Survival rate, MDA of the tissue, histology and ultra-microstructure were examined.
RESULTSSurvival rate of A, B, C, D were improved in order. Statistic difference is significant (P < 0.05) between group and group other than C and D. The content of MDA was heightened with statistically significant differences (A > B > C > D) among the four groups 8 hours postoperatively, but fell back to the normal level in group D and C and kept a high level in group A and B at 72 hour postoperatively. Histology and ultra-microstructure exam showed that degeneration of collagen fiber and karyopyknosis of cell is more obvious in Group A and Group B than Group C and Group D.
CONCLUSIONSThe higher survival rate of venous flap is possible by designing the more reasonable venous flap outputs pedicles which can alleviate the high tension dropsy and maintain the valid equilibrium of pour with flow in the venous flap.
Animals ; Graft Survival ; Rabbits ; Surgical Flaps ; blood supply ; Veins ; transplantation
5.Hyperthermia enhanced the killing effect of 5-fluorocytosine on human colon cancer cell line transfected with cytosine deaminase gene.
Jin-mao LI ; Cheng-jin LI ; Da-nian LAI ; Xiao-jun WANG ; Xian-li HE ; Guo-qiang BAO ; Tao WU ; Ji-kai YIN
Chinese Journal of Gastrointestinal Surgery 2006;9(3):234-237
OBJECTIVETo investigate whether hyperthermia can enhance the killing effect of 5- fluorocytosine (5- FC) on human colorectal carcinoma cell lines SW480 transfected with carcinoembryonic antigen (CEA) tissue- specific cytosine deaminase (CD) gene in vitro,and study its mechanism.
METHODSHuman colorectal carcinoma cell lines SW480 transfected with G1CEACDNa were cultured. The proliferated colonies were treated with the combined therapy of 5-FC and hyperthermia at a temperature of 43 degrees C for 30 min. After eight days, MTT was used to calculate the cellular survival rate,to analyze the killing effect of 5-FC combined with hyperthermia on SW480 cells transfected with CD gene. Flow cytometry was performed to analyze the cellular cycle and transmission electron microscope was used to observe the morphologic changes of SW480 cells after thermochemotherapy.
RESULTSHyperthermia combined with 5-FC had an enhanced killing effect on SW480-CEACD cells than 5-FC alone (P< 0.05, t =2.403, n=9). Flow cytometry revealed that the proportion of S stage cell increased in the group treated with hyperthermia and 5- FC (P< 0.001, t =7.158, n=6). Transmission electron microscope showed apoptosis after thermo- chemotherapy.
CONCLUSIONSHyperthermia can improve the anti- tumor effect of 5- FC on human colorectal carcinoma cell lines SW480 transfected with CD gene, and the cells were blocked at S stage of cellular cycle and apoptosis was induced following thermochemotherapy.
Cell Line, Tumor ; Cytosine Deaminase ; genetics ; Flucytosine ; pharmacology ; Genes, Transgenic, Suicide ; Genetic Therapy ; methods ; Hot Temperature ; Humans
6.Clinical analysis of factors affecting colorectal adenoma recurrence after endoscopic resection
Wen-Jing LIU ; Xiao-Na HU ; Da-Nian JI ; Ren-Xiang HUANG ; Zhi-Jun BAO
Fudan University Journal of Medical Sciences 2018;45(2):185-190
Objective To analyze the factors that might affect the recurrence after endoscopic resection of colorectal adenoma,we aim to provide a reference for the regular follow-up of colorectal adenoma after endoscopic resection.Methods In the Department of Gastroenterology,Huadong Hospital from Jan.,2013 to Dec.,2014,patients received endoscopic resection during hospital stay and postoperative follow-up colonoscopy.We collected their information of gender,age,smoking history,drinking history,hypertension,diabetes,fatty liver,cholecystectomy history,Helicobacter pylori (H.pylori) infection,related metabolic indicators,number of adenoma,size of adenoma,location of adenoma and pathology of adenoma.Multivariate and univariate analysis were performed by Logistic regression analysis to explore factors influencing the recurrence risk of colorectal adenoma.Results A total of 283 cases were enrolled.The recurrence rate of low-risk and high-risk adenoma was 39.3 % and 56.3 %,respectively,and therate of all adenoma was 52.7%.Multivariate and univariate analysis both found that H.pylori infection (P<0.001,OR:3.316 and 2.802,95%CI:1.869-5.884 and 1.660-4.728) and adenoma number (P<0.001,OR:2.799 and 2.789,95% CI:1.578-4.963 and 1.667-4.668) were risk factors for colorectal adenoma recurrence after endoscopic excision.Conclusions H.pylori infection and the number of base colorectal adenoma maybe associated with colorectal adenoma recurrence.