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Biomedical subjects

Li Li

Publications and source records attributed to Li Li.

At least 559 records · Page 31Linked to original sources

Screening of augmenter of liver regeneration-binding proteins by yeast-two hybrid technique.

OBJECTIVE: To investigate the biological function of augmenter of liver regeneration (ALR), we used yeast-two hybrid technique to detect proteins in hepatocytes interacting with ALR. METHODS: ALR bait plasmid was constructed by using yeast-two hybrid system 3, then transformed into yeast AH109. The transformed yeast was mated with yeast Y187 containing liver cDNA library plasmid in a 2XYPDA medium. Diploid yeast was plated on a synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing x-alpha-gal for selection and screening. After extracting and sequencing of the plasmid from blue colonies. Analysis was performed by bioinformatics. RESULTS: Of 36 colonies sequenced, 14 are metallothionein, 12 albumin, and 3 selenoprotein P. One colony is a new gene with unknown function. CONCLUSION: The successful cloning of gene of ALR interacting protein has paved the way for studying the physiological function of ALR and associated proteins.

Animals↗

[Inhibition of tongue cancer development in nude mice transfected with adenovirus carrying human endostatin gene].

BACKGROUND & OBJECTIVE: The squamous cell carcinoma of tongue is one of the most common malignant tumors of oral cavity. Surgical therapy is now the mainstay of combined treatment for tongue squamous cell Carcinoma with chemotherapy and radiotherapy. The overall 5-year survival rate was about 50%. The antiangiogenesis therapy has become a new approach of the treatment of tongue carcinoma. This paper was designed to study the characteristics of endostatin expression in tongue cancer cell line (Tca8113), human embryonic epithelial cell line (ECV) and the inhibition of carcinogenesis in nude mice, xenografted with Tca8113, after transfected with recombined adenovirus (Ad/hEnd) which was cloned with human endostatin gene in EI mutated region. METHODS: (1) To determine the expression and distribution of endostatin in Tca and ECV cells transfected with Ad/hEnd using immunohistochemistry. To determine the endostatin in supernatants of Tca cells transfected with Ad/hEnd using ELISA method. To examine the characteristics of endostatin gene expression in Tca8113 and ECV cells by Western blot analysis. (2) To determine the inhibition rate of proliferation and apoptosis rate of ECV cells by WST-1 test and flow cytometry (FCM), respectively.(3) To observe the inhibition of tumor growth in xenografted nude mice with Tca8113 cells by Ad/hEnd administration. RESULTS: (1) Immunohistochemistry detection indicated that the endostatin was expressed in cytoplasm of Tca8113 cells and ECV cells transfected with Ad/hEnd. Endostatin expression in the supernatant was dose-dependent with the highest to 597 ng/ml. The expression of endostatin in Tca cells was detectable from 1 day to 7 day. Ad/hEnd inhibited ECV cell growth in dose-dependent manner. (2) FCM showed that Ad/hEnd arrested ECV cells in S and G(2) phase and induced apoptosis.(3) The tumor growth curve showed that Ad/hEnd significantly repressed xenograft tumor growth with Tca cell in nude mice; the inhibition rate on Ad/hEnd administrated groups was 45.8% in the 3rd week. CONCLUSION: Ad/hEnd expressed efficiently in Tca8113 and ECV cells. Ad/hEnd can change the cell cycle distribution of ECV cells and induce apoptosis and inhibit proliferation of ECV cells. Ad/hEnd could inhibit the growth of tongue carcinoma in xenograft nude mice.

Adenoviridae↗

[Early recurrent factors of ovarian cancer after treatment].

BACKGROUND & OBJECTIVE: Recurrence of ovarian cancer is an important factor that leads to therapeutic failure. At present, the treatment in ovarian cancer is not sufficiently effective. This study was designed to investigate the factors of early recurrence after treatment in ovarian cancer in order to reduce its recurrence. METHODS: The clinical data of the ovarian cancer patients admitted to Affiliated Hospital of Guangxi Medical University during January 1986 to May 1996 who recurred within one year after treatment were analyzed retrospectively. The recurrent rates were compared according to their different clinical stages, pathological types, and residual volumes of the disease as well as the number of courses of pre and postoperative chemotherapy received. Chi-square test was used for statistic analysis. RESULTS: Eighty-two of 373 cases recurred within one year after treatment; the overall recurrent rate was 22.0%. The 1-year recurrent rate in stage I-II patients was lower than that in stage III-IV patients (2.7% versus 30.3%, P< 0.01). The recurrent rate in the patients with undifferentiated adenocarcinoma was higher than that with other pathological type. The recurrent rate in the patients with residuals >or=2 cm was higher than that with residuals < 2 cm (33.8% versus 13.7%, P< 0.01). The recurrent rate in the patients with preoperative chemotherapy was lower than that without it. The recurrent rate in the patients who had received only 1-3 courses of postoperative chemotherapy was higher than that having received 4-6 or >6 courses (67.0% versus 7.7%, 67.0% versus 7.0%, respectively, P< 0.01). CONCLUSION: Early (1-year) recurrence in the patients with ovarian cancer seems to be closely related to late stage of the disease, incomplete surgery, and insufficient chemotherapy courses.

Adolescent↗

[Pollution of EHEC O157:H7 in six types of food in Henan Province].

In order to investigate the distribution of contamination of EHEC O157:H7 in 6 types of food in Henan Province and characterize the effect of seasonal factors on distribution of O157:H7 contamination so as to prevent and control food contamination, Henan Province was divided into five sampling areas according to the natural geographical features. Samples were taken randomly in summer and winter sales links. After selective culture of increasing reproduction of O157:H7, it was screened by immuno-gold reagent, and pathogenic bacterium were isolated after accumulation of immunomagnetic. Then, it was identified by the bioMérieux VITEK32 AMS system, GNI+ and sero-reaction. Results showed that 28 EHEC O157:H7 were isolated in 1463 samples among which the positive rate of raw meat and fresh vegetable was 3.3% and 3.2% respectively (the highest of all), and EHEC O157:H7 was not found in yogurt. The positive rate in summer (2.5%) was obviously higher than that in winter (1.1%). It could be concluded that the contamination of EHEC O157:H7 in food was serious. Its positive rate was positively correlated with the epidemic of infective diarrhea. Therefore, attention should be given by relevant departments concerned and spervision and testing should be strengthened in livestock and farmyard bird slaughtering link, vegetable production link and sales link for better prevention of the breaking out and epidemic of food born diseases.

Animals↗

[Ultrasonography via vaginal in diagnosing uterine anomalies].

OBJECTIVE: To investigate the clinical value of ultrasonography via vaginal in diagnosing uterine anomalies. METHODS: Patients in Infertility Clinic were scanned by endovaginal sonography. Hysterosalpingography (HSG) or hysteroscopy were performed in patients with uterine anomalies confirmed by ultrasonography. RESULTS: Twenty patients had uterine anomalies. Of them, 10 had double uterus, 4 had bicornuate uterus, 3 arcuate uterus, 2 septate uterus, and the other 1 unicornuate uterus. CONCLUSION: Uterine anomalies are easily detected by endovaginal sonography. The diagnosis of uterine anomalies is important in the treatment of infertility and in the prevalence of complications related to uterine anomalies such as abortion and premature labor in pregnancy.

Adult↗

[Refolding and purification of Plasmodium falciparum glutamate dehydrogenase fusion protein].

OBJECTIVE: To establish the method for renaturation and purification of the fusion protein of Plasmodium falfiparum (FCC1/HN ) glutamate dehydrogenase (GDH) with glutathione S-transferase (GST). METHODS: The recombinant plasmid GDH/pGEX-4T-1, encoding the full-length GDH gene, was transformed into E.coli BL21 (DE3) to achieve IPTG-induced high expression of GDH/GST in the form of inclusion bodies identified by SDS-PAGE. After denaturation with 8 mol/L urea, the inclusion bodies were subjected to 3 different renaturation methods, namely Sephacryl S-200 chromatography, dialysis and dilution, for refolding of the fusion protein. The refolded GDH/GST was then purified by different chromatographic approaches. RESULTS: SDS-PAGE analysis showed that the expression GDH/GST fusion protein mounted up to approximately 25% of the total bacterial protein. The dilution was better than the other two methods for the refolding of the fusion protein, with the optimized renaturation condition necessitating the presence of 20 mmol/L Tris-HCl and 1 mmol/L EDTA at pH8.5 with GSSG/GSH ratio of 1 10, which resulted in a recovery rate exceeding 90%. Two-step ion exchange chromotography was optimal for purification of the fusion protein. CONCLUSION: The high-purity and biologically active GDH/GST can be acquired by dilution renaturation followed by two-step ion exchange chromatography.

Animals↗

[Expression of human TRAIL gene in COS-7 cells and its effects in the treatment of hepatic carcinoma].

OBJECTIVE: To study the therapeutic potential of TRAIL and in combination with subtoxic level of chemotherapeutic agents in the treatment of human hepatocellular carcinomas (HCCs). METHODS: The plasmid pcDNA 3.0-hTRAIL was transfected into COS-7 cells, and it was transiently expressed. The cytotoxic functions of the expressed product and in combination with chemotherapeutic agents were detected. RESULTS: The transiently transfected COS-7 could express the active human TRAIL. It had mild cytotoxic functions on HCC cell lines. The cytotoxicity rates in both cell lines were 9.2% and 9.5% respectively. Chemotherapeutic agents, mitomycin (M), 5-FU and actinomycin D (AcD) dramatically augmented TRAIL induced cytotoxic function. There were significant differences in the cytotoxicity between the use of single agent and in combination with TRAIL (TRAIL + M, M; 60.1%, 32.6%, TRAIL + 5-FU, 5-FU: 68.1%, 29.2%, TRAIL + AcD, AcD; 72.9%, 58.6%) (P < 0.05). CONCLUSIONS: The combination of human TRAIL and chemotherapeutic agents, such as mitomycin, 5-FU and actinomycin D, seemed to exert a synergistic effect compared with either agent alone, and it might have therapeutic potential in the treatment of human HCC.

Animals↗

[Study on the epidemiology and distribution of human immunodeficiency virus-1 and hepatitis C virus infection among intravenous drug users and illegal blood donors in China].

OBJECTIVE: To determine the epidemiologic features and distribution of human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV) infection among intravenous drug users and illegal blood donors in China. METHODS: Polymerase chain reaction (PCR) amplification and DNA sequencing were used to evaluate the HIV-1 gag p17 and env C2-V3 regions, as well as the HCV 5'NCR and E1/E2 regions. RESULTS: Among 239 subjects with reported HIV-1 infection, 56.9% (136/239) were seropositive for anti-HCV. Of those, 96.3% (131/136) were co-infected with HCV through intravenous drug use and illegal blood donation. Intravenous drug users in Yunnan, Guangxi and Xinjiang provinces were infected with HIV-1 subtype C and HCV genotypes 1b, 3a, 3b and 4, whereas illegal blood donors in Henan province harbored HIV-1 subtype B' and HCV genotypes 1b and 2a. Five different HIV-1 subtypes were identified among 17 HIV-1-infected individuals from Beijing. CONCLUSIONS: Multiple HIV-1 subtypes and HCV genotypes were identified in China which were associated with several different modes of transmission. Homogeneity within the sequences of the two viruses suggested the recent, but separate, outbreaks of HIV-1 and HCV infection. The distinct distribution patterns of HIV-1 and HCV genotypes in two high-risk groups seemed to be more closely linked to the mode of transmission than to geographic proximity.

Adolescent↗

[Phase II clinical trial on gemcitabine in the treatment of stage IIIB-IV non-small cell lung cancer].

OBJECTIVE: To evaluate the efficacy and safety of domestic Gemcitabine in the treatment of patients with stage IIIB approximately IV non-small cell lung cancer (NSCLC). METHODS: 124 NSCLC patients were randomized into three groups: Group A: single drug group, 40 cases, gemcitabine 1 000 mg/m(2) + NS 100 ml or 200 ml was infused within 30 approximately 60 minutes on D1, 8 and 15, with 28 days taken as one cycle. Group B: combined treatment group, 36 cases, in addition to the above protocol, cisplatin 30 mg/m(2) was infused within 60 approximately 120 min, on D1, 2 and 3. Group C: combined control group: 39 cases, the protocol applied was the same as group B except domestic gemcitabine being replaced by imported gemzar. The efficacy and side effects of treatment were evaluated after 8 weeks of treatment. RESULTS: 115 patients could be evaluated for response rate. PR was observed in 9/40 (22.5%) of group A, 15/36 (41.6%) in group B and 15/39 (38.36%) in group C. There was no significant difference of PR rates between group B and group C (P = 0.552). 117 patients who received the second cycle of treatment were evaluated for toxicity. The incidence of grade III approximately IV nausea, vomiting and loss of appetite was much higher in group B. Hematological toxicity of groups B and C was higher than that of group A. There was no significant difference between groups B and C. CONCLUSION: The efficacy and incidence of side effects between domestic gemcitabine and the imported gemzar are similar.

Carcinoma, Non-Small-Cell Lung↗

[Application of CD34+ autologous peripheral progenitor cell transplant in the treatment of children with refractory SLE].

OBJECTIVE: Systematic lupus erythematosis (SLE) is a severe disease which affects the patient for many years and there is no radical cure for the disease. To explore a possible way to treat children with refractory SLE, the authors treated 2 children with grade III and IV lupus nephropathy for 5 years and 7 years respectively, mainly presented with persistent thrombocytopenia, proteinuria, pleural effusion with CD34(+) autologous peripheral progenitor cells transplantation. METHODS: Mobilized with G-CSF and collected with CS-3000 Cell Separator, passed through the CliniMacs CD34(+) cell selection device, the count of CD34(+) cells obtained reached 1.0 x 10(6)/kg and 1.7 x 10(6)/kg, respectively with the remaining of 2.0 x 10(5)/kg and 1.0 x 10(4)/kg of CD3(+) cells individually. The selected CD34(+) cells were frozen at -80 degrees C. The conditioning regimen consisted of cyclophosphamide [50 mg/(kg x day) for 4 days] plus ATG [Fresennius S 5 mg/(kg x day) for 3 days]. After 48 h treatment with cyclophosphamide, the frozen stem cells were infused back to the patients. RESULTS: Neutrophils recovered on 9 and 7 days after transplantation respectively in these 2 cases. Beginning from 15 days, the platelet count recovered and remained at over 100 x 10(9)/L. The sign of Cushing's syndrome disappeared completely 3 months after transplantation because discontinuing the steroid. One child's height had a 5 cm increase within 6 months after stopping steroid and this was the first height gain during the 7 years since she had had the disease. Till this paper was written, these 2 children were followed up for 13 months and 6 months, respectively, all the original symptoms and autoantibodies related to autoimmune disorders disappeared. But the cell-mediated immunity did not recover yet with the CD4(+) cell level still remained at a lower level. CONCLUSION: The effect of CD34(+) autologous peripheral progenitor cell transplantation on the children with refractory SLE was satisfactory so far, but the long-term effect remains to be confirmed by further studies on more cases.

Adolescent↗

[Studies on the chemical constituents from the water-soluble part of Euphrasia regelii].

OBJECTIVE: To study the chemical constituents from the water-soluble part of Euphrasia regelii. METHOD: The compounds were isolated by macroporous resin and column chromatography, and identified by IR, NMR data. RESULT: Two special compounds were isolated and identified. CONCLUSION: Two compounds were isolated from this plant for the first time.

Euphrasia↗

Effect of alpha2M on earthworm fibrinolytic enzyme III-1 from Lumbricus rubellus.

Though it is known that human alpha2-macroglobulin (alpha2M) inhibits most proteases, the effect of alpha2M has not been investigated on earthworm fibrinolytic enzymes (EFEs) from Lumbricus rubellus, which could be transported from intestine epithelium into blood as an intact molecule (Fan et al., Biochim. Biophys. Acta 1526 (2001) 286). The activity of earthworm fibrinolytic III-1 (EFE-III-1) decreased to 65% when incubated with alpha2M, while it decreased to 30% in plasma under the same conditions. The first order rate of the inactivation of EFE-III-1 with alpha2M was similar to that of fast phase with plasma, indicating that alpha2M may be the inhibitor initially binding to the enzyme in blood. SDS-PAGE showed that incubation of EFE-III-1 with alpha2M a released fragment ( approximately 90 kDa), followed by formation of a high molecular weight complex (approximately 700 kDa). There was a linear relationship between the apparent inhibition rate constant (k1) and [alpha2M], by double reciprocal plot. It was suggested, as described by Tsou (Acta Biochem. Biophys. Sinica 5 (1965) 398) and Tian (Biochem. J. 21 (1982) 1028), that the mechanism of alpha2M/EFE-III-1 interaction could be coincided with a complexing irreversible inhibition. Experiments in both the inactivation and the intrinsic fluorescence showed that alpha2M bound to the enzyme mole by mole equivalently. The intrinsic fluorescence of alpha2M was enhanced with an observable blue shift in emission maxima, suggesting that alpha2M was one of the important inhibitors to EFEs when it absorbed into blood.

Animals↗

[Primary biliary cirrhosis: an analysis of 153 cases].

OBJECTIVE: To study the clinical, immunological and pathological features of primary biliary cirrhosis (PBC). METHODS: Clinical and laboratory data of 153 patients with PBC treated in our hospital were retrospectively analyzed. Of these patients, 35 underwent hepatic biopsy. RESULTS: Typical manifestations such as itch of skin and hepatosplenomegaly etc. were found in only 39.2% to 46.4% of the patients and jaundice was seen in 84.3%. The serum level of SB was gradually increased while that of CHE decreased along with progression of PBC (P < 0.01). The level of serum Albumin and ALT was significantly lower in late stage than in the early stages (P < 0.05). ALT and CHE were not correlated with SB. AST level was markedly higher in the late stage than in the early stage (P < 0.05). The levels of ALP and GGT rose at the early stage but remarkably decreased at the middle stage (ALP, P < 0.05) and at the late stage (GGT, P < 0.01). The positive rate of AMA was 83.7% and that of M2 69.3%. As for the 35 patients receiving hepatic biopsy, 10 were AMA positive and the other 25 AMA negative. CONCLUSION: More than half of the patients with PBC do not exhibit typical clinical symptoms and over 80% of the cases of PBC can be diagnosed by investigation of clinical features and detection of AMA and M2. For some cases that can not be definitely diagnosed by observation of clinical features, the final diagnosis should be determined by hepatic biopsy.

Adolescent↗

(-)-CGP 12177 increases contractile force and hastens relaxation of human myocardial preparations through a propranolol-resistant state of the beta 1-adrenoceptor.

Two forms of the activated beta1-adrenoceptor exist, one that is stabilized by (-)-noradrenaline and is sensitive to blockade by (-)-propranolol and another which is stabilized by partial agonists such as (-)-pindolol and (-)-CGP 12177 but is relatively insensitive to (-)-propranolol. We investigated the effects of stimulation of the propranolol-resistant beta1-adrenoceptor in the human heart. Myocardium from non-failing and failing human hearts were set up to contract at 1 Hz. In right atrium from non-failing hearts in the presence of 200 nM (-)-propranolol, (-)-CGP 12177 caused concentration-dependent increases in contractile force (-logEC50[M] 7.3+/-0.1, E(max) 23+/-1% relative to maximal (-)-isoprenaline stimulation of beta1- and beta2-adrenoceptors, n=86 patients), shortening of the time to reach peak force (-logEC50[M] 7.4+/-0.1, E(max) 37+/-5%, n=61 patients) and shortening of the time to reach 50% relaxation ( t(50%), -logEC50[M] 7.3+/-0.1, E(max) 33+/-2%, n=61 patients). The potency and maxima of the positive inotropic effects were independent of Ser49Gly- and Gly389Arg-beta1-adrenoceptor polymorphisms but were potentiated by the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (-logEC50[M] 7.7+/-0.1, E(max) 68+/-6%, n=6 patients, P<0.0001). In the presence of (-)-propranolol and 3-isobutyl-1-methylxanthine, the potency (-logEC50[M] 7.4+/-0.1, P=0.0013, n=9 patients) but not the maximal effect of (-)-CGP 12177 was reduced in right atrium from failing hearts, which was associated with 64% and 52% reductions in the densities of low-affinity and high-affinity (-)-[3H]CGP 12177 binding sites. In the presence of (-)-propanolol and 3-isobutyl-1-methylxanthine, (-)-CGP 12177 increased atrial cyclic AMP levels and activated cyclic AMP-dependent protein kinase in right atrium from non-failing hearts. In right ventricle from failing hearts (-)-CGP 12177 increased contractile force (-logEC50[M] 7.4+/-0.1, E(max) 34+/-3%, n=13 patients) and hastened the time to peak force (-logEC50[M] 7.6+/-0.1) and time to reach 50% relaxation (-logEC50[M] 7.4+/-0.1) in the presence of (-)-propranolol and 3-isobutyl-1-methylxanthine. Our results show that (-)-CGP 12177 increases contractility and hastens relaxation through a cyclic AMP pathway in human myocardium, consistent with mediation through a (-)-propranolol-resistant state of the beta1-adrenoceptor. The reduction in heart failure of atrial inotropic potency of (-)-CGP 12177, as well as of the high-affinity and low-affinity binding sites for (-)-[3H]CGP 12177, is consistent with the beta1-adrenoceptor nature of these sites.

Adrenergic beta-1 Receptor Agonists↗

Microsatellite instability in thorotrast-induced human intrahepatic cholangiocarcinoma.

Thorotrast, a colloidal suspension of radioactive (232)ThO(2) that emits alpha particles, was used as a radiographic contrast during World War II. It is known to induce liver cancers, most frequently ICC, decades after injection. Since radiation induces genomic instability, we analyzed MSI in Thorotrast-induced ICC. The frequency of MSI(+) cases was 62.5% in Thorotrast ICC, whereas it was 22.7% in non-Thorotrast ICC. However, frameshift mutations of mononucleotide repeats were not observed in Thorotrast ICC. In addition, the MSI(+) phenotype was not associated with the quantity of Thorotrast deposited or the latency period of ICC induction. Promoter regions of both the hMLH1 and the hMSH2 MMR genes tended to be hypermethylated in the tumor part compared to the adjacent nontumor part in Thorotrast ICC. Methylation of the hMLH1 promoter was associated with the MSI(+) phenotype in Thorotrast ICC. In contrast, methylation status of these promoter regions was not related to MSI in non-Thorotrast ICC cases. These findings suggest that MSI induced by exposure to Thorotrast mainly reflects clonal expansion of cancer cells and is partly due to inactivation of hMLH1 by hypermethylation.

Adaptor Proteins, Signal Transducing↗