1.Determination of serum tryptophan metabolites in patients with systemic lupus erythematosus by high performance liquid chromatography-fluorescence detection
Zhongyuan XIANG ; Aiguo TANG ; Yaping REN ; Qianxuan ZHOU
Chinese Journal of Clinical Laboratory Science 2006;0(01):-
Objective A method was developed for the simultaneous determination of tryptophan(Trp) and its metabolites kynurenine(Kyn) and kynurenic acid(Kyna) by high performance liquid chromatography with fluorescence detection(HPLC-FD),and testing serum levels of Trp metabolites in systemic lupus erythematosus(SLE) patients.Methods Serum samples were deproteinized by equal volume of 0.624 mol/L perchloric acid.The analytical column was Hypersil C18 column,and the mobile phase was 0.20 mol/L zinc acetate,8.3 mmol/L acetic acid,and 2.5% acetonitrile;flow rate was 1.5 ml/min.The excitation and emission wave length of fluorescence detector were 365 nm and 480 nm in 0~11 min,344 nm and 404 nm in 11~15.5 min,254 nm and 404 nm in 15.5~20 min,respectively.Results The linear range of Trp was 0.610~196 ?mol/L,the detection limit was 0.005 ?mol/L,and the average recovery was 103.71%.The linear range of Kyn was 0.049~98 ?mol/L,the detection limit 0.025 ?mol/L,and the average recovery was 97.45%.The linear range of Kyna was 1.050~1047 ?mol/L,the detection limit was 0.050 nmol/L,and the average recovery was 100.60%.Inter-and intra-day precisions were both less than 5%.Phenylalanine,tyrosine,and 5-hydroxytryptamine had no interference.The assay was employed to analyze serum samples of SLE patients.The result showed significant difference in Trp,Kyn,and Kyna content,Kyn/Trp ratio between SLE patients and control group.Conclusions A new method was established for simultaneous determination of Trp,Kyn,and Kyna in serum.The method is simple,fast,sensitive,specific,and suitable for applicability to clinical measurement.
2.Mechanism underlying docosahexaenoic acid-induced regulation of angiopoietin expression in human brain vascular pericytes subjected to oxygen-glucose deprivation and restoration: the relationship with SSeCKS
Yanli YU ; Zhongyuan XIA ; Haibin FANG ; Bin ZHOU ; Shaoqing LEI
Chinese Journal of Anesthesiology 2017;37(2):188-191
Objective To evaluate the relationship between the mechanism underlying docosahexaenoic acid (DHA)-induced regulation of angiopoietin expression and Src-suppressed C kinase substrate (SSeCKS) in human brain vascular pericytes (HBVPs) subjected to oxygen-glucose deprivation and restoration (OGD/R).Methods HBVPs were seeded in 96-well or in 6-well plates at a density of 2× 105 cells/ml and divided into 5 groups (n =18 each) using a random number table:control group (group C),OGD/R group,DHA group (group D),SSeCKS gene silencing group (group S) and SSeCKS gene silencing plus DHA group (group SD).The model of OGD/R injury was established as follows:the cells were subjected to O2-glucose deprivation for 24 h in glucose-and serum-free culture medium aerated with 94% N2-5% CO2-1% O2 followed by restoration of O2-glucose supply for 6 h in high-glucose DMEM culture medium in normal atmosphere.DHA was added at 1 h before hypoxia with the final concentration of 40 μmol/L in group D.Small interfering RNA induced SSeCKS gene silencing in S and SD groups.Subsequently,DHA with the final concentration of 40 μmol/L was added at 1 h before hypoxia in group SD.At 6 h of reoxygenation,the cell survival rate was determined by CCK-8 assay,the amount of LDH released was detected using ELISA,and the expression of SSeCKS,angiopoietin-1 (Ang-1) and Ang-2 was detected by Western blot.Results Compared with group C,the cell survival rate was significantly decreased,the amount of LDH released was increased,the expression of SSeCKS and Ang-1 was down-regulated,the expression of Ang-2 was up-regulated,and Ang-1/Ang-2 ratio was decreased in group OGD/R,and the expression of SSeCKS was down-regulated in group S (P<0.05).Compared with group OGD/R,the cell survival rate was significantly increased,the amount of LDH released was decreased,the expression of SSeCKS and Ang-1 was up-regulated,the expression of Ang-2 was down-regulated,and Ang-1/Ang-2 ratio was increased in group D (P<O.05),and no significant change was found in the parameters mentioned above in group SD (P>0.05).Compared with group D,the cell survival rate was significantly decreased,the amount of LDH released was increased,the expression of SSeCKS and Ang-1 was down-regulated,the expression of Ang-2 was up-regulated,and Ang-1/Ang-2 ratio was decreased in group SD (P<0.05).Conclusion The mechanism by which DHA increases the ratio of Ang-1/Ang-2 may be totally related to up-regulation of SSeCKS expression in HBVPs subjected to OGD/R.
3.Effect and Mechanism of Dexmedetomidine Hydrochloride on Neuropathic Pain
Yingcong YANG ; Kang LIU ; Fang ZHOU ; Qingtao MENG ; Zhongyuan XIA
Herald of Medicine 2017;36(3):252-255
Objective To establish neuropathic pain models,explore the effects and mechanisms of dexmedetomidine on neuropathic pain.Methods Wistar rats were randomly divided into four groups (n =9):0.9% sodium chloride solution CCI group (N),dexmedetomidine CCI group (D),ZD7288 CCI group (Z) and sham-operated group (Sham).Sciatic nerve ligation was performed in group N,D and Z.The sciatic nerve in group Sham was exposured without ligation.7 d after surgery,the rats in group D were intraperitoneal injected with dexmedetomidine (40 μg· kg-1),and the rats in group Z were intraperitoneal injected with ZD7288 (10 mg·kg-1)once a day for 3 d.The same volume of 0.9% sodium chloride solution was given at the same time in group N.The behavioral test was performed before and 7 d after operation,as well as 3 d after injection treatment.Mechanical allodynia was assessed by paw withdrawal mechanical threshold (PWMT) to von Frey filaments.Thermal hyperalgesia was assessed by paw thermal withdrawal latency (TWL) to radiant heat.Dexmedetomidine block of HCN channels in dorsal root ganglion (DRG) neurons were confirmed by whole-cell recording.Results 7 d after surgery,the PWMT and TWL of rats in group N,D and Z were decreased significantly (P < 0.05).The PWMT and TWL in group Sham were no significant difference before and after operation.Dexmedetomidine significantly increased the levers of PWMT and TWL in group D and Z after treatment for 3 d,and group Z was greater than group D (P < 0.05).Dexmedetomidine (0.1,1,10 μmol· L-1) caused a concentration-dependent decrease in the amplitude of Ih in DRG neurons from (-844.43 ± 386.34) to (-215.99 ± 63.90) pA (P < 0.05),and the inhibition rate of Ih was (11.87 ± 1.80) %,(35.26 ± 3.65) % and (52.02 ± 5.56) %,respectively(P <0.05).Dexmedetomidine produced a dose-related shift to the left of the Ih activation,and a negative shift in V1/2 (P < 0.05).V1/2 shifted from (-86.21 ± 1.68) to (-103.54 ± 2.01) mV (P < 0.05).The slope values were not altered by dexmedetomidine.Conclusion Dexmedetomidine produces a dose-dependently analgesic effect on neuropathic pain after peripheral never injury,which is likely due to the inhibition of Ih and reduction of ectopic spontaneous discharge in DRG neurons.
4.Clinical characteristics and drug resistance of 176 strains of candida isolated from children with blood infections
Zhongyuan HE ; Xiuzhen ZHOU ; Jianhua LIU ; Zhijie ZHANG ; Yong LIU
Chinese Pediatric Emergency Medicine 2016;23(7):471-475
Objective To analyze the pathogen distribution and drug resistance of candida isolated from children with blood infections in our hospital,and to provide reference for clinical effective prevention and treatment.Methods The blood specimens of pediatric patients were collected between January 2009 and December 2015,and were cultured using BacT/ALERT 3D and BD9140 instruments.The candida were separated with Sobaurandps agar culture medium,and identified with chromogenic medium,API 20CAUX test strips or VITEK-2 compact YST card.The minimal inhibitory concentration of 5 drugs were determined by ATB FUNGUS 3 system.Results In 176 cases,92 strains (52.3%) were from neonatal ward,and 46 strains (26.1%) were from PICU.In newborn group,85 strains were isolated from premature,which contained the low and very low birth weight infants (37 strains),pneumonia(20 strains),neonatal respiratory distress syndrome(9 strains).In PICU,the strains were commonly isolated from children with severe infection.Among 176 strains of candida,71 strains (40.3%) were C.albicans,62 strains (35.2%) were C.parapsilosis,16 strains(9.1%) were C.glabrata,9 strains(5.1%) were C.tropicalis,and 18 strains(10.2%) belonged to other candida.Conclusion Candida blood infections can happen at all age of chlidren.The most common strains detected from blood were C.albicans,followed by C.parapsilosis.Most of these strains are susceptible to antifungal drugs,such as fluconazole,except C.glabrata.The sensitive rates to commonly used antifungal drug are more than 93%.The selection of antifungal drugs should be based on the species of strains.
5.Anti-cytomegalovirus (CMV) effect of antisense oligodeoxynucleotides phosphorothioates (AS S OND)
Tianji ZHOU ; Xueyi ZHANG ; Hao ZHANG ; Lijun WANG ; Zhongyuan RENG ;
Chinese Pharmacological Bulletin 1986;0(04):-
AIM To study anti CMV effect of S ODNs complementary to the initial code region of major immediate early (MIE) mRNA, and to the intron1/exon2 boundary of MIE mRNA precursor. METHODS To evaluate the anti CMV effect by determining viral antigen on infected 2BS cells by in situ ELISA. RESULTS Both of 2 AS S ODNs and their sense sequence control showed anti CMV effect. The medium effective concentration (EC 50 ) were 4 53, 10 2, 26 2 and 30 1 ?mol?L -1 . The secretion of CMV antigens were delayed by 3 d~4 d by 8 0 ?mol?L -1 AS 1. It showed increased effect by administrating earlier postinfection, by supplementing the S ODN at intervals, by conbinating with ganciclovir, and by packaging with liposome. A slight cytotoxicity was observed at the concentration of 64 0 ?mol?L -1 . Northern blot analysis indicated that the MIE mRNA decreased after the treatment of AS 1. It suggests that disintegration of the mRNA in the hybridized duplex by activated RNase H played an important role as the mechanism of specific action, and "time and effect" analysis suggested that interference of viral adsorbtion and penetration may be the important mechanism of nonspecificity. CONCLUSION AS S ODNs targeted to MIE gene are effective anti CMV agents which can be developed as a new type of chemotherapy drugs against CMV infection.
6.Intestinal flora and ischemic stroke
Zhongyuan LI ; Huanhuan SUN ; Mengmeng GU ; Xiangliang CHEN ; Junshan ZHOU
International Journal of Cerebrovascular Diseases 2021;29(4):307-313
The brain-gut axis is an important pathway for the interaction between the central nervous system and the gastrointestinal tract. Ischemic stroke can promote the imbalance and displacement of intestinal flora, and the intestinal flora and its metabolites in turn can affect the occurrence, development and outcome of ischemic stroke. This article reviews the related literature on ischemic stroke and intestinal flora, in order to review the relationship between the two and related mechanisms, and to prospect the stroke treatment of targeting intestinal flora.
7.Effects of obesity on insulin resistance, β-cell function and serum high-sensitivity C-reactive protein level in first-degree relatives of type 2 diabetic patients
Xiaolin CHEN ; Jing LI ; Zhongyuan WEN ; Yonglin SUN ; Ying WANG ; Xiaoli CAI ; Bo ZHOU ; Zhenjin LI
Chinese Journal of Endocrinology and Metabolism 2008;24(5):521-522
Insulin sensitivity,β-cell function and serum high-sensitivity C-reactive protein (hs-CRP)levels were observed in obese and non-obese normoglycemic first-degree relatives of type 2 diabetic patients (FDR). The results showed that there existed insulin resistance,β-cell dysfunction and increased serum hs-CRP level in obese FDR of type 2 diabetic patients. Moreover, insulin resistance and increased CRP level were positively related to waist circumference.
8.Role of PTEN in diabetes mellitus-induced reduction of hypoxic postconditioning-induced protection of cardiomyocytes: the relationship with GSK-3β-mediated mitochondrial apoptotic pathway
Rui XUE ; Zhongyuan XIA ; Shaoqing LEI ; Bo ZHAO ; Qingtao MENG ; Wei LI ; Bin ZHOU
Chinese Journal of Anesthesiology 2017;37(1):108-111
Objective To evaluate the role of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in diabetes mellitus-induced reduction of hypoxic postconditioning (HPO)-induced protection of cardiomyocytes and the relationship with glycogen synthase kinase-3β (GSK-3β)-mediated mitochondrial apoptotic pathway.Methods H9c2 cells incubated in high-glucose (30 mmol/L) medium for 24 h were divided into 6 groups (n =5 each) using a random number table:normoxia group (group N),hypoxia-reoxygenation (H/R) group,group HPO,PTEN gene silencing normoxia group (group P-N),PTEN gene silencing H/R group (group P-H/R),and PTEN gene silencing HPO group (group P-HPO).H9c2 cells were exposed to 95% N2-5% CO2 for 4 h followed by 2 h reoxygenation with 90% O2-10% CO2.HPO was induced by 3 cycles of 5 min reoxygenation followed by 5 min hypoxia before reoxygenation.At the end of reoxygenation,the level of lactate dehydrogenase (LDH) in the supernatant was detected by enzyme-linked immunosorbent assay,the changes in mitochondrial membrane potential (MMP were assessed by JC-1 fluorescence assay,the cell apoptosis was detected by AnnexinV-FITC/PI flow cytometry,and the expression of PTEN and phosphorylated GSK-3β (p-GSK-3β) was determined by Western blot.The JC-1 monomer/polymer ratio and apoptosis rate were calculated.Results Compared with group N,the amount of LDH released,JC-1 monomer/polymer ratio and apoptosis rate were significantly increased,and the expression of PTEN was up-regulated in H/R and HPO groups (P<0.05).There was no significant difference in the parameters mentioned above between group H/R and group HPO (P>0.05).Compared with group HPO,the amount of LDH released,JC-1 monomer/polymer ratio and apoptosis rate were significantly decreased,PTEN expression was down-regulated,and the expression of p-GSK-3β was up-regulated in group P-HPO (P<0.05).Compared with group N,the expression of PTEN was significantly down-regulated,and no significant changes were found in the other parameters mentioned above in group P-N (P>0.05).Compared with group H/R,the expression of PTEN was significantly down-regulated,and no significant changes were found in the other parameters mentioned above in group P-H/R (P>0.05).Conclusion PTEN is involved in diabetes mellitus-induced reduction of HPO-induced protection of cardiomyocytes,and the mechanism is associated with PTEN-induced activation of GSK-3β-modulated mitochondrial apoptotic pathway.
9.Preparation and Evaluation of Triptolide Self-microemulsifying Drug Delivery System
Jiawei CAO ; Jun FENG ; Xinjun CAI ; Jianjun NI ; Lunan GU ; Zhongyuan ZHOU
China Pharmacist 2017;20(4):638-642
Objective:To study the formula of triptolide (TRI) self-microemulsifying drug delivery system (SMEDDS) and evaluate the pharmaceutical properties.Methods:The formula and preparation process of triptolide self-microemulsion were screened by the solubility test and pseudo-ternary phase diagram.With the average particle size and self-microemulsifying time as the indices,the further formula optimization of triptolide self-microemulsion was carried out.The pharmaceutical properties of triptolide self-microemulsion were evaluated.Results:The optimal formula of TRI SMEDDS was as follows:the amount of medium chain triglycerides (MCT) was 20%,that of polyoxyethylene castor oil (EL-35) was 40%,and that of polyethylene glycol 400 (PEG-400) was 40% in the oil phase.The average particle size was 43.48 nm,and the time of self-microemulsification was less than 30 s.Conclusion:The average particle size and the appearance of triptolide self-microemulsion are accordance with the requirements of pharmaceutics.Triptolide self-microemulsion has good sustained-release effect,which lays foundation for the further study on pharmacodynamics.
10.On Key issues of Public Hospitals Reform
Haichao LEI ; Guang SHI ; Ying WU ; Hongli NIU ; Xiao WEI ; Xiaoyuan ZHOU ; Zhongyuan LI ; Chunyan XIE
Chinese Journal of Hospital Administration 2010;26(4):241-243
Public hospital reform pilots have been initiated recently and it is necessary to clarify some key issues. To this end, thispaper touches upon six fundamental issues, discussing the generality and value for the existence of public hospitals, differences between reforms of public hospital and those of state-owned enterprise, the public financing for and regulation on public hospitals, relationship with the private sector, as well as service and function positioning of public hospitals.