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H Cui

Publications and source records attributed to H Cui.

At least 109 records · Page 6Linked to original sources
PubMed1996

[Generation of genetic engineering anti-idiotypic antibody against OC125 monoclonal antibody of ovarian carcinoma].

OBJECTIVES: To amplify and express the variable region genes of murine derived anti-idiotypic monoclonal antibody and to develop a new kind of ovarian carcinoma vaccine. METHODS: mRNA was prepared from murine hybridoma which produces anti-idiotypic antibody against OC125. The heavy and light chain variable region genes (VH and VL) were amplified by polymerase chain reaction (PCR), joined by DNA linker fragments to form single chain FV gene (ScFv), and were ligated into phage mid vector, pCANTAB 5E. The recombinant vector was induced into competent E. coli TG1 cells. The phage displayed recombinant antibodies were detected and identified by enzyme-linked immunosorbent assay (ELISA). RESULTS: The VH, VL and ScFv genes were 340 bp, 325 bp and 750 bp respectively. Some of the transformed clones expressed engineered anti-idiotypic antibodies, which could specifically bind to the original antibody (OC125). CONCLUSIONS: Genetic engineering anti-idiotypic antibody against OC125 monoclonal antibody was successfully generated. Clinical application of anti-idiotypic antibody to immunotherapy and to prevention of ovarian carcinoma may be studied.

Animals↗
PubMed1996

[A clinical study in the treatment of acute bacterial infections with fleroxacin].

The purpose of this clinical trial is to evaluate the efficacy and safety of fleroxacin and to compare with those of lomefloxacin. A randomized controlled study was carried out to treat sixty patients with urinary tract and respiratory tract bacterial infections, thirty in each group with one of the two drugs, and fifty cases were treated with fleroxacin in an open trial. Altogether there were one hundred and ten cases. Both fleroxacin and lomefloxacin were given orally, the dosage was 200 mg every 12 hours or 400 mg every 24 hours for 7-14 days. The clinical efficacy rate was 93.3%; the culturing rate in the fleroxacin group was 83.3%; the bacterial clearance rate was 92.3%, the incidence of adverse reactions was 9.4%, while in the lomefloxacin group they were 90.0%, 80.0%, 87.5% and 6.7% respectively, with no statistically significant difference between the two groups (P > 0.05). In the open and randomized trials, fleroxacin cured eighty cases of bacterial infections, the overall clinical efficacy rate was 90.0%, the culturing rate in the flero-xacin group was 83.8%, the bacterial clearance rate was 88.2% and the incidence of adverse reactions was 9.6%. It is shown that fleroxacin is an antibiotic of broad-spectrum, high efficacy and safety.

Adult↗
PubMed1995

Expression, promoter usage and parental imprinting status of insulin-like growth factor II (IGF2) in human hepatoblastoma: uncoupling of IGF2 and H19 imprinting.

We have studied the promoter utilization and parental imprinting status of human IGF2 in three genetically informative hepatoblastomas from patients ranging in age from 9 months to 3 years. In all three cases, there is a downregulation of promoter P1 in the tumor tissues while the P2 and P3 promoters are upregulated compared to the normal liver. One of three patients displayed loss of imprinting (LOI) of IGF2 in the tumor tissue. We also investigated the expression of the H19 gene in all three cases and the methylation pattern in H19 from the patient with LOI of IGF2. The expression of H19 was greatly reduced in all tumors. Monoallelic H19 expression however, was retained even in the case which showed LOI of IGF2. Unlike the situation in Wilms' tumor, no differences in the methylation pattern between the normal liver and tumor tissues were observed in the H19 promoter or 3' region, using HpII analysis. We show here, that in contrast to the situation in Wilms' tumor, H19 expression is not a prerequisite for maintaining a monoallelic IGF2 expression.

Alleles↗
PubMed1995

Protection against Fas-dependent Th1-mediated apoptosis by antigen receptor engagement in B cells.

Cytotoxic CD4+ Th1-cells induce cell death by triggering a Fas-dependent apoptotic pathway. Potential targets include activated B cells, but it is not known whether the mode of B-cell stimulation influences susceptibility to Th1-mediated cytotoxicity. Here we report that CD40-ligand-stimulated B cells were extremely sensitive, whereas anti-IgM-stimulated B cells were resistant, to Fas-mediated apoptosis. B cells stimulated by both CD40L and anti-IgM were not susceptible to cytolysis, demonstrating that anti-IgM-mediated protection is an active, dominant process. Resistance to Th1-mediated cytotoxicity was similarly observed in CD40L-stimulated 3-83 (anti-H-2Kk,b) transgenic B cells co-cultured with H-2Kk or H-2Kb (but not H-2Kd) splenocytes. These results indicate that B cells can participate in regulating their own destruction. Protection against Fas-dependent apoptosis afforded by immunoglobulin-receptor engagement may constitute a fail-safe mechanism that eliminates bystander B cells activated by CD40L-expressing T cells, but ensures survival of antigen-specific B cells.

Animals↗
PubMed1995

Fas(CD95)/FasL interactions required for programmed cell death after T-cell activation.

Receptor crosslinking of T-cell hybridomas induces cell activation followed by apoptosis. This activation-induced cell death requires de novo synthesis of RNA and proteins, but the actual gene products that provide the death signal have not been identified. We show here that receptor crosslinking induces Fas ligand and upregulates Fas, and that the ensuing engagement of Fas by Fas ligand activates the cell-death programme. Cell death, but not activation, can be selectively prevented by a soluble Fas-immunoglobulin fusion protein. Thus, Fas and Fas ligand are the death-gene products, and their interaction accounts for the molecular mechanism of activation-induced T-cell death.

3T3 Cells↗
PubMed1995

Monoallelic expression of IGF2 at the human fetal/maternal boundary.

IGF2 is expressed in both placental and decidual tissues, enabling an analysis of the parental imprinting over the fetomaternal boundary. Evidence is provided that IGF2 is monoallelically expressed in both placenta and pregnant, as well as nonpregnant, endometrium. These observations suggest that the maternally derived IGF2 allele is inactivated during germline transmission. Comparison of promoter usage in decidua and placental samples shows that the P3 promoter appears to regulated independently of the others. These observations are discussed with respect to current models of IGF2 imprinting and the hypothesized conflict of parental reproductive interests which bears on the phenomenon of parental imprinting.

Alleles↗
PubMed1995

The molecular mechanism of FasL-mediated cytotoxicity by CD4+ Th1 clones.

Murine CD4+ Th1 clones require de novo synthesis of proteins to express a cytotoxicity that is mediated by de novo synthesized Fas ligand (FasL). The cytotoxic process of the CD4+ Th1 effectors can be separated into four stages, namely conjugate formation, activation, lethal hit, and effector-independent target cell death. The present study describes the cytotoxic process in terms of FasL induction and Fas/FasL molecular interactions for death signal transduction. Fas-Ig fusion proteins, cycloheximide, actinomycin D, and EGTA+MgCl2 were used to analyze each stage of the cytotoxic process in terms of FasL/Fas participation. The results demonstrate that the activation-induced de novo mRNA and protein synthesis were for FasL, which provided the predominant cytotoxic activity of CD4+ Th1 effectors. Once activated, Th1 effectors express cytotoxic activity in the presence of EGTA+MgCl2, an experimental [Ca2+]ext-independent condition characteristic of FasL-mediated cytotoxicity. The ability of Fas-Ig to inhibit target lysis declined rapidly after conjugate formation, indicating that FasL-mediated lethal hit is critically dependent on conjugate formation and, once delivered, the effector-independent target lysis proceeds. After the lethal hit stage, transduction of Fas-mediated death signal was independent of de novo synthesis of macro-molecules in targets because treatments that inhibited more than 98% of the macromolecule synthesis had little effect on target lysis. Our study provides the first molecular view in terms of FasL/Fas of the cytotoxic process of CD+ Th1 cells.

Animals↗
PubMed1995

Synthesis and application of hepatitis E virus peptides to diagnosis.

Based on computer analysis of hydrophobicity and prediction of secondary structures for the full-length putative proteins encoded by open reading frame-1 (ORF-1), ORF-2 and ORF-3 of hepatitis E virus (HEV), we selected antigenic regions with hydrophilicity, beta-turn, and beta-sheet, and synthesized 7 peptides of possible epitope-containing regions of the polypeptide encoded by all 3 ORFs of HEV genomic RNA by Merrifield's method of solid-phase synthesis. The synthetic peptides were screened and identified by solid-phase enzyme-linked immunosorbent assay (ELISA). Three of the peptides (EH174 from ORF-1, EH286 from ORF-2 and EH362 from ORF-3) showed antigenic activity and possible application for the development of anti-HEV test kits (the peptide-based ELISA). The laboratory experiments and clinical trials showed that the kits, using a set of 3 synthetic HEV peptides as coating antigens, were of high specificity and exhibited good reproducibility. The small-scale seroepidemiological survey indicated high seroprevalence (14.3%) of anti-HEV in Tibetan populations. Additionally, the results also demonstrated good agreement with clinical findings, suggesting that the test kits will be of major use for immunodiagnosis and seroepidemiological surveys of HEV infection.

Amino Acid Sequence↗
PubMed1995

Promoter-specific IGF2 imprinting status and its plasticity during human liver development.

IGF2 has been shown to be expressed preferentially from the paternally derived allele, although the maternal allele can be found active during both prenatal and postnatal development as well as in neoplastic tumours in humans. We addressed here whether or not the biallelic expression patterns that can be seen during postnatal human liver development reflected a coordinated change in the activities of the four promoters of human IGF2. We show here that the P2, P3 and P4 promoters, but not the P1 promoter, display monoallelic activity in embryonic, neonatal and younger infant liver specimens. The P2, P3 and P4 promoters can, however, be found active either monoallelically or biallelically or even monoallelically on opposite parental alleles in older infant and adult liver specimens. In contrast, H19, which is closely linked to IGF2, is monoallelically expressed in all postnatal liver samples analysed. We conclude that the functional imprinting status of IGF2 during postnatal liver development appears to be promoter/enhancer-specific and either partly or completely independent of H19.

Alleles↗
PubMed1995

[Establishment and biological characteristics of the nude mice xenograft model from human hepatocellular carcinoma].

The human hepatocellular carcinoma was successfully heterotrasplanted into nude mice and 10 passages were made seriously during 11 months. Initial take rate was 14.3% and then the take rate increased to 100% after the 3rd passage. Histological, morphological, ultrastructural and biological investigation and chromosome analysis showed that the characteristic of transplanted tumor was identical to that of characteristics of human donor tumor. Through serial passages no metastatic signs were found grossly and under the microscope in the lymph nodes, liver and lung of the nude mice. Result also showed that the model retained some functions of the original tumor. The transplanted tumor could secret a-fetoprotein (AFP), r-glufamyl transpeptidase (r-GT). Acidic isoferritin (AIF) also could be detected. The tumor tissue of xenograft model was cultured in vitro in order to develop a permanent cell line. We found that the tumor specimen of the later passages grew more rapidly than the earlier ones. Up to now 3 cell passages were made. In this paper, a reliable animal model of human hepatocellular carcinoma is provided for studies of clinical diagnosis, treatment, antitumor drug screen test, etc.

Aged↗
PubMed1995

Therapeutic effects of the combined Chinese and Western medicine on metastatic carcinoma in the supraclavicular lymph nodes--an analysis of 285 cases.

Between 1985 and 1989, 285 cases of metastatic carcinoma in the supraclavicular lymph nodes were treated by the following five methods: Chinese medication, radiotherapy plus Chinese medication, chemotherapy plus Chinese medication, combined Chinese and Western medicine and expectant treatment. Analysis shows that radiotherapy plus Chinese medication has the best curative effect with an effective rate of 75.5%. The effective rates were 74.2% for the combined treatment, 55.5% for the chemotherapy plus medication, 12.5% for the Chinese medication, and none for expectant treatment.

Adult↗
PubMed1995

Light microscopic radioautographic study on DNA synthesis of nerve cells in the cerebella of aging mice.

The morphological change and DNA synthesis of nerve cells in the cerebella of the aging mice were investigated by light microscopic radioautography using tritiated thymidine injection in vivo. During a period ranging from late fetal life to certain postnatal stages, 9 groups of mice were used. The labelled nuclei, which involved both the precursors of neurons and the glioblasts, were observed in the external granular layer of the cerebellum from embryonic day 19 to postnatal day 14. It disappeared completely at 1 month. A peak of labeling index was observed at postnatal day 3. The glioblasts of the external granular layer migrated inward, some of them forming the Bergmann glia cells located between Purkinje cells, this at postnatal day 8, some penetrating in the internal granular layer. Labelled nuclei in the internal granular layer were also observed and a maximum of the labeling was seen at postnatal day 3, similarly to the external granular layer. With the development and the expansion of the cerebellum, the endothelial cells of the cerebellar vessels were progressively labelled, reaching a maximum during the first postnatal week. The obtained results provided consequently some data on the age-related changes of DNA synthesis of mouse cerebellum from later embryonic stages to postnatal stages. Different investigations will be necessary to explain these irregular sequences of labeling.

Aging↗
PubMed1994

Participation of target Fas protein in apoptosis pathway induced by CD4+ Th1 and CD8+ cytotoxic T cells.

The results presented here provide evidence that the presence of Fas protein in target cells is essential to permit cytotoxicity (resulting in apoptosis) mediated by cloned CD4+ Th1 cells. Using mitogen-activated B cells as targets, antigen-dependent lysis by CD4+ Th1 effectors was observed with MRL/MpJ+ but not with MRL/MpJ-lpr targets. The congenic MRL/MpJ-lpr strain is defective in Fas expression. Target cells from various lymphoid tissues of C3H.MRL-lpr mice were also resistant to the lectin-dependent cytotoxicity of Th1 effectors, whereas C3H/HeJ targets were sensitive. Moreover, a rapid DNA fragmentation prior to 51Cr release was induced only in C3H/HeJ targets. Thus, cytotoxicity induced by Th1 effectors correlates with target Fas expression. In contrast to Th1 effectors, CD8+ cytotoxic T lymphocytes (CTLs) killed C3H.MRL-lpr targets. When cytotoxicity was assayed in the presence of EGTA and MgCl2, which chelates extracellular Ca2+ [(Ca2+)ext], only C3H.MRL-lpr targets became resistant to CD8+ CTLs. This (Ca2+)ext-independent cytotoxicity of both Th1 and CD8+ effectors could be inhibited with unlabeled C3H/HeJ thymocytes or with a transfectoma carrying a murine Fas-human mu gene construct. In comparison, C3H.MRL-lpr thymocytes and the nontransfected parental cell line were poor inhibitors. Our study demonstrates that CD4+ Th1 cells and CD8+ CTLs differ in their (Ca2+)ext-dependent cytotoxicity but share a (Ca2+)ext-independent cytotoxicity that requires participation of Fas molecules for cytotoxic signal transduction leading to target apoptosis.

Animals↗
PubMed1994

NMDA receptor activation in differentiating cerebellar cell cultures regulates the expression of a new POU gene, Cns-1.

POU/homeobox genes encode transcription regulatory proteins that are important in defining cellular phenotypes. Expression of these genes may be critical for to the regulation of CNS cellular differentiation. We have identified a cDNA corresponding to a new member of the POU/homeobox gene family. Expression of RNA encoded by this new gene occurs predominantly in the CNS. Thus, this new gene was designated Cns-1. Cns-1 transcripts are expressed in differentiating cells cultured from the early postnatal cerebellum. Treatment of these cultured cells with NMDA results in an increase in the level of Cns-1 RNA. This increase is blocked by simultaneous treatment with the specific NMDA receptor antagonist amino-5-phosphonovaleric acid. Continued activation of the NMDA receptor allows maintenance of this new steady state level of Cns-1 mRNA for at least 5 d in these cultured cells. A transcription runoff assay suggests that this increase in the level of RNA is due, at least in part, to an increase in transcription from the Cns-1 gene. The NMDA-induced increase in Cns-1 mRNA was reduced by pretreatment with calcium chelators EGTA or 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) tetrakis(acetoxymethyl). These studies suggest that specific activation of the NMDA receptor in cultures of differentiating cerebellar cells increases Cns-1 gene expression and that calcium entry through the NMDA channel may be required for this response. This change in Cns-1 expression may modify phenotypic characteristics of these cultured cells.

Amino Acid Sequence↗
PubMed1994

[Studies on the relationship between HPV and respiratory tract tumors. I. Correlation between HPV and laryngeal carcinoma].

In this paper, alpha-32P-dCTP-labeled HPV-11 and HPV-16 DNA were used as probe, and slot and Southern blot hybridization techniques were used to detect HPV-11 and HPV-16 DNA related sequences in 37 laryngeal carcinoma tissues taken from patients in Qingdao and Beijing. Using the slot blot technique, 86% (32/37) of the cases showed positive hybridization with HPV-11 probe, while 81% (30/37) showed positive results with HPV-16. Another 81% (30/37) showed positive hybridization with HPV-11 and HPV-16 simultaneously. Using Southern blot hybridization Pst digestion, the hybridization pattern corresponded to that of HPV-16 in 46; (13/28), and none corresponded to HPV-11. The results suggest that HPV-16 may induce laryngeal carcinoma.

Adult↗
PubMed1994

A study of c-myc oncogene expression and amplification in colorectal cancer.

Expression of c-myc oncogene transcripts in colorectal neoplasia was studied in paraffin embedded tissue sections from 25 patients undergoing surgery and from the rectal carcinoma cell line HR-8348 by using in situ hybridization, and its amplification was investigated in tumor and normal mucosa tissue from 25 coloproctomy samples by slot blot hybridization. Overexpression of this gene was seen in 78% (7/9) of the benign adenomas and 91% (20/22) of the malignancies sampled. There was no significant correlation between overexpression and the histologic type or grade, and no significant relationship between the level of expression and clinical stage was found, although overexpression was apparently more common in tumors with metastasis. Amplification of the gene was found in 0 of 4 benign adenomas and 7 of 22 malignancies. No obvious correlation was found between amplification and histological type or grade, though amplification was more frequent in tumors with metastasis. Amplification was also found in 2 adenomas with malignant change. The results suggest that multiple factors are involved in the progression of colorectal cancer, and in situ hybridization with a nonradiolabeled probe is useful in the detection of gene expression.

Adenocarcinoma↗
PubMed1993

[Characterization of two antigens OC41 D and OC41 E associated with ovarian carcinoma].

Two antigens, OC41D and OC41E, were characterized by two monoclonal antibodies (COC41D and COC41E) generated with the antigens (OC41) as immunogen, which were dissociated from immune complex in a patient with ovarian carcinoma. The expressing rates of the antigen OC41D and OC41E were 70.2% and 52.5% in epithelial ovarian cancer. They were mainly detected on the membrane of the cancer cells, also a little in the plasma. Two antigens were found no cross reactivities with HIA, CEA, alpha-FP, and beta-MG. Their express were not related to cell circle. Antigen OC41D might be a protein with molecular weight of 62,000 and could not be denatured by heating. Antigen OC41E might be a glycoprotein with molecular weight of 15,000. These two antigens may be new antigens highly associated with ovarian carcinoma.

Antibodies, Monoclonal↗