1.Enantiomeric Separation of Three Kinds of Aromatic Amino Acids by C18 Column Tandem Crown Ether Chiral Column
Yujian LIU ; Zhimin LIU ; Zhigang XU
Chinese Journal of Analytical Chemistry 2017;45(3):369-373
A reversed phase high performance liquid chromatographic ( RP-HPLC ) method was proposed by using C18 column tandem crown ether chiral column for simultaneous separation of three kinds of aromatic amino acid enantiomers. The chromatographic conditions, including mobile phase proportion, pH, column temperature and flow rate, were optimized. The experimental results showed that the three aromatic amino acid enantiomers could be successfully separated under the optimal conditions such as perchloric acid solution-acetonitrile ( 86:14, V/V, pH = 2 ) as mobile phase, column temperature of 20℃ and flow rate of 0. 4 mL/min. The separation under four HPLC column connection modes was further investigated. The results revealed that different kinds of amino acids could be separated on C18 column, but not for amino acid enantiomers; amino acid enantiomers could be separated on crown ether chiral column, but the chromatographic peaks of each amino acid enantiomers overlapped seriously; baseline separation of three amino acid enantiomers could be obtained under the connection of two columns, but the separation under different column connection sequence almost had no difference except the peak shape.
2.Clinical correlative factors of malignant cystic pancreatic tumors
Xiaodan LI ; Yujian LIU ; Liwei ZHU
Chinese Journal of Digestive Surgery 2012;11(4):343-345
Objective To investigate the clinical correlative factors of malignant cystic pancreatic tumors.Methods The clinical data of 45 patients who received cystic pancreatic tumor resection at the General Hospital of Tianjin Medical University from May 2000 to May 2011 were retrospectively analyzed.All patients were divided into benign tumors + precancerous lesions group (35 patients) and malignant tumor group (10 patients).The clinical symptoms and imaging features of cystic pancreatic tumors were analyzed.All data were analyzed by chisquare test or Logistic regression analysis.Results Abdominal pain,jaundice,emaciation,nausea and vomiting were observed in 23 patients (51%),and 22 (49%) patients had no clinical symptoms.The clinical features of benign pancreatic cyst included pancreatic calcification and pancreatic divisum,while the clinical features of malignant pancreatic cystic tumors were nodules,swelling of lymph nodes,dilation of biliary and pancreatic duct.The results of univariate analysis showed that age ≥ 60 years,presence of symptoms,jaundice,emaciation,dilation of pancreatic duct were the correlative factors of malignant cystic pancreatic tumors ( x2 =4.220,4.294,4.645,7.705,4.645,P < 0.05 ).The results of multiple logistic regression analysis found that age ≥60 years,dilation of pancreatic duct and presence of clinical symptoms were the correlative factors of malignant cystic pancreatic tumors ( OR =1.573,2.674,2.723,P < 0.05).Conclusion Age≥60 years,dilation of pancreatic duct and presence of clinical symptoms are the correlative factors of malignant cystic pancreatic tumors.
3.Biological significance of glucocorticoid receptor beta
Yujian LIU ; Liangnian SONG ; Jian LU
Chinese Journal of Pathophysiology 2001;17(8):783-
Alternative splicing of the human glucocorticoid receptor (hGR) primary transcript produces two receptor isoforms, termed hGRα and hGRβ. hGRα is a ligand-activated transcription factor which, in the hormone-bound state, modulates the expression of glucocorticoid-responsive genes by binding to specific glucocorticoid response element (GRE) DNA sequences. In contrast, hGRβ dose not bind glucocorticoids and is transcriptionally inactive. We demonstrate here that hGRβ inhibits the hormone-induced, hGRα-mediated stimulations of gene expression, including glucocorticoid-responsive reporter gene (cat) and endogenous p21 gene. We also demonstrate that hGRβ can inhibit hGRα-mediated regulation of proliferation and differentiation of a human osteosarcoma cell line (HOS-8603). Our studies on the expression of hGR mRNA in nephrotic syndrome patients indicate that the hGRα/hGRβ mRNA ratio in peripheral white blood cell of hormone-resistant patients is lower than that of hormone-sensitive patients and health volunteers. These results indicate that hGRβ may be a physiologically and pathophysiologically relevant endogenous inhibitor of hGRα
4.Structure and function of Mac-1 and its role in cancer immunotherapy
Fei DIAO ; Xiaoyan ZHU ; Yujian LIU
China Oncology 2001;0(03):-
Mac-1,an adhesion molecule expressed on the surface of leukocytes,plays an important role in host-defence function and immunological response.It consists of two noncovalently linked polypeptides known as ?(CD11b) and ?(CD18) subunits.It contains two important domains known as I-domain which recognizes protein ligands and the lectin domain which recognizes polysaccharides.Mac-1 is expressed on nearly all neutrophils,monocytes,eosinophils and NK cells,but less on B cells,T cells and macrophages.Mac-1 functions as both an adhesion molecule for ICAM-1 expressed by stimulated endothelium mediating the diapedesis of leukocytes across the endothelium and a receptor for the iC3b fragment of complement responsible for cytotoxicity to microorganisms or target cells opsonized with iC3b.It can also form a complex with many membrane glycoproteins,functioning as a signal transducing partner for them.An important finding was that soluble ?-glucan could bind to Mac-1 and prime the receptor for cytotoxic function in response to iC3b-opsonized tumors,thus may pave the way for development of ?-glucan-like drugs that could generate Mac-1-dependent cytotoxicity following a humoral response to tumor antigens elicited by vaccines that would cause tumors to be opsonized with Abs and iC3b in cancer immunotherapy.
5.Effect of VDR on the proliferation regulated by 1,25-dihydroxyvitamin D_3 in human osteosarcoma cell line HOS-8603
Yuxia CHEN ; Yujian LIU ; Liangnian SONG
Chinese Journal of Pathophysiology 2000;0(10):-
AIM: To explore the possible role of the vitamin D receptor (VDR) in the effect of 1,25-dihydroxyvitamin D 3 and its novel analogues on a human osteosarcoma cell line (HOS-8603) proliferation. METHODS: Detecting the VDR mRNA and protein expression in HOS-8603 cells by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical analysis, respectively. Using the method of transient transfection of a reporter gene (DR3-tk-CAT) for VDR to detect its function. The cell VDRas3 which stably expressed VDR antisense mRNA was used to observe the effect of 1,25(OH) 2 D 3 on the proliferation of HOS-8603 cells and the induction of p21 mRNA, one of the VDR target genes, when the VDR in the cells was blocked. RESULTS: HOS-8603 cells expressed the vitamin D receptor which functioned as a hormone-dependent transcriptional factor. When VDR in the HOS-8603 cells decreased, the cells lost the responsiveness to 1,25(OH) 2 D 3 irrespective of either the induction of p21 gene expression or the cell proliferation. CONCLUSION: The effect of 1,25(OH) 2 D 3 on the proliferation of the human osteosarcoma cell line HOS-8603 was mediated by its nuclear receptor VDR.
6.Effects of glucocorticoids on the glucocorticoid receptor ? and ? mRNA expression
Yujian LIU ; Liangnian SONG ; Jian LU
Chinese Journal of Pathophysiology 1986;0(03):-
AIM: To clarify the effects of glucocorticoids on the messenger RNA expression of glucocorticoid receptor (GR? and GR?). METHODS: messenger RNA of GR ? and GR? were determined by quantitive RT-PCR. RESULTS: Besides GR? mRNA, GR? mRNA is also expressed in human osteosarcoma cell line HOS-8603, human ovarian carcinoma cell line 3AO and human peripheral white blood cells. After administration of dexamethasone, both GR? mRNA and GR? mRNA were down-regulated in a time-dependent and dose-dependent manner. CONCLUSION: GR? expresses in various kinds of human tissue cells. The expression of GR? is regulated by glucocorticoids.
7.Signal transduction and mechanisms of integrin CD18 expression regulated by PMA
Xiaowen HE ; Yujian LIU ; Zhen PAN ; Jigen ZHONG ; Jia LU
Chinese Journal of Pathophysiology 1989;0(05):-
AIM: To investigate the effect of PMA(phorbol 12-myristate 13-acetate) on the expression of CD18 and the mechanism. METHODS: The technique of quantitative RT-PCR analysis was used to measure the expression of CD18 mRNA in U937 cells treated by PMA. RESULTS: PMA could significantly induce CD18 mRNA expression in a dose and time-dependent manner. The induction effects of PMA on CD18 mRNA could be inhibited obviously by Myr (2 ?mol/L), a specific inhibitor of PKC, and APDC, an inhibitor of NF-?B, but not be inhibited by curcumin, a inhibitor of transcriptional factor AP-1. CONCLUSION: PMA enhanced the expression of CD18 via the pathway of PKC. Transcriptional factor NF-?B, but not AP-1, was essential for the gene transcription of CD18 in U937 cells treated by PMA.
8.Effect of glucocorticoid receptor beta on the transactivation function of glucocorticoid receptor alpha
Yujian LIU ; Liangnian SONG ; Yuxia CHEN ; Jian LU
Chinese Journal of Pathophysiology 2000;0(10):-
AIM: To investigate the effect of glucocorticoid receptor beta(GR?) on the transcriptional activation function of glucocorticoid receptor alpha(GR?) and elucidate the biological significance of glucocorticoid receptor beta. METHODS: GR? (pRSH-GR?) and GR? responsive reporter gene cat (pMMTV-cat) were cotransfected into human osteosarcoma cell line (HOS-8603). Transient transfectants were treated with dexamethasone and the activity of cat was determined by the method of ELISA. The expression p21 messenger RNA was detected by the method of reverse transcription-polymerase chain reaction. RESULTS: GR? repressed the expression of reporter gene-cat in a dose-dependent manner. The expression of messenger RNA of p21, an endogenous target gene of GR?, was also inhibited by GR?. CONCLUSION: GR? can inhibit the transcriptional activation function of GR?. GR? may be an endogenous inhibitor of GR?.
9.Role of p21~(wafl)in the proliferation and differentiation of the human osteosarcoma cell line(HOS-8603) regulated by 1,25(OH)_2D_3
Yuxia CHEN ; Yujian LIU ; Liangnian SONG ; Jian LU
Chinese Journal of Pathophysiology 1986;0(03):-
AIM: To explore the possible role of p21 wafl gene in the effect of 1,25-dihydroxyvitamin D 3 on a human osteosarcoma cell line (HOS-8603) proliferation and differentiation. METHODS: The effect of 1,25(OH) 2D 3 on the expression of p21 wafl mRNA was determined by quantitative reverse transcription-polymerase chain reaction. The human osteosarcoma cell line stably expressing the p21 wafl mRNA, which named HOS-p21 wafl , was constructed by lipofectamine transfection, and the expression of p21 wafl protein was detected by Western blot. Then the growth curve of the HOS-p21 wafl cells and the expression of alkaline phosphatase (AKP) in the HOS-p21 wafl cells were investigated. RESULTS: The expression of endogenous p21 wafl mRNA in HOS-8603 cells was induced by 1,25(OH) 2D 3 in a time-dependent manner, reaching the maximum at 4 h, and remaining the inducible action for up to 24 h over basal levels. The HOS-p21 wafl cells grew much slower than the control cells, only reaching 50% of the control ones when cultured for up to 6 days. Histochemical analysis showed that the expression of alkaline phosphatase (AKP) in the HOS-p21 wafl cells increased remarkably.CONCLUSION: These results suggest that the p21 wafl mRNA expression induced by 1,25(OH) 2D 3 is one of important mechanisms responsible for the cellular effects of the hormone on HOS-8603 cells.
10.Laparoscopic treatment of abdominal and retroperitoneal cystic masses in 11 children
Weize HU ; Yujian DAI ; Zhen LIU ; Tong YE ; Yingjun WANG
Chinese Journal of Applied Clinical Pediatrics 2021;36(1):54-58
Objective:To explore the feasibility and efficacy of laparoscopic resection of abdominal and retroperitoneal cystic masses in children.Methods:A retrospective analysis of 11 cases of abdominal and retroperitoneal cystic masses in Department of Pediatric Surgery, Quanzhou First Hospital Affiliated to Fujian Medical University from June 2015 to January 2019 was performed, and all the patients underwent laparoscopic resection or laparoscopic-assisted resection, with 6 cases of boys and 5 cases of girls, aged 8 months to 10 years (with the average of 59 months). Meanwhile, 9 cases were from the abdominal cavity and 2 cases were from the retroperitoneum.Results:All patients underwent laparoscopic or laparoscopic-assisted resection without switching to laparotomy.The operation time was 60-210 minutes, with the average of 120 minutes.The intraoperative blood loss was 5-30 mL, with the average of 10 mL.There was no blood transfusion.All patients were discharged 3-8 days after surgery, with the average of 5 days.The postoperative pathological results included 5 cases of mature teratoma, 1 case of paraneoplastic cyst, 2 cases of intestinal duplication, 2 cases of lymphangioma, and 1 case of hepatic cyst.Totally, 11 cases were followed up for 7-51 months, with the average of 20.9 months.No recurrence occurred.Conclusions:Laparoscopic or laparoscopic-assisted resection of abdominal and retroperitoneal cystic masses has advantages of minimal invasion, rapid recovery in children, and it is safe and effective.