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H Wei

Publications and source records attributed to H Wei.

At least 163 records · Page 9Linked to original sources
PubMed1997

[Fully length MDR1 cDNA transfer conferring resistance to adriamycine on sensitive cells GLC].

Human lung cancer leads the mortality of cancers and the chemotherapy is often uneffective because of drug resistance. In order to study the role of mdr-1 gene in resistant lung cancer, the fully length mdr-1 cDNA was transferred into a sensitive lung cancer cell line GLC. The mdr-1 cDNA was constructed in a retroviral vector, pDORneo. The transfection of recombinant plasmid was carried out by lipofectin. Supernatant containing infective viruses derived from a G418 resistant clone of package cell PA317 was used to infect GLC cell which is sensitive to chemotherapeutic agents. After G418 and adriamycine selections, three P-glycoprotein positive clones were isolated and the integration of mdr-1 cDNA was demonstrated by PCR of genomic DNA. The relative resistance of 3 clones to adriamycine as and elevated by 5.4, 6.0 respectively 7.8 times compared with the untransfected cell and the transcription of mdr-1 gene in these transfected cells as obviously enhanced by in situ hybridization. This results suggest that the mdr-1 gene plays a role in increasing drug resistance of human lung cancer.

Adenocarcinoma↗
PubMed1997

[The effects of pressure on cultured bovine trabecular meshwork cells].

OBJECTIVE: To observe the effects of pressure on trabecular meshwork cells. METHODS: Bovine trabecular meshwork cells were cultured and submitted to different amounts of hydrostatic pressure. Cellular morphology and phagocytic function were observed under inverted phase-contrast microscope, light microscope and electron microscope. RESULTS: Compared with the control group, the cells under 2.0 kPa or 2.67 kPa for 48 hours had no remarkable difference in criteria observed. Those under 4.0 kPa for 24 hours showed slight changes in structure and a mild decrease in phagocytic function. The damage appeared more severe if the pressure was higher or lasted longer. CONCLUSION: Trabecular meshwork cells can only bear pressure below a certain level. They may be destroyed structurally or impaired functionally by pressure over this level.

Animals↗
PubMed1997

[A three-dimensional anisotropic finite element analysis of modified bar-clip implant-borne overdenture in the edentulous mandible under punching loads].

The stress distributions of the modified bar-clip implant-borne overdenture in the edentulous mandible were performed under punching loads with both porcelain and resin chosen as the restorative materials by means of three-dimensional anisotropic finite element method. The purpose of this study was to investigate the patterns of stress distributions and to compare the effect of different restorative materials on the stress distributions under punching loads. The results showed that the value of stress peaks in implants with porcelain restorations seemed higher than those with resin restorations. On the contrary, in the bone-implant interface had little difference, except a comparative uniform stress distribution found in resin restorations. It implies that resin restoration produces a cushioning effect on reducing the stress peaks in implants themselves under punching loads. Both porcelain and resin restorations can be chosen as the restorative materials because of a little influence on the stress peaks in bone-implant interface under punching loads.

Adult↗
PubMed1997

[Sertindole, a novel alpha 1A-adrenoceptor selective antagonist].

The antagonism effect of sertindole on alpha 1-AR subtypes was studied by combining radiologand binding assays in three cloned alpha 1-AR subtypes stably expressed in human embryonic kidney 293 cells and contractile response experiment in isolated rat blood vessels. The results showed that the affinity for sertindole in the cloned alpha 1A-AR (pKI 8.90 +/- 0.17) was 69-fold (pKI 7.06 +/- 0.09) and 132-fold (pKI 6.78 +/- 0.07) higher than that for the cloned alpha 1B- and alpha 1D-AR, respectively. The pA2 values for sertindole in antagonizing NE-induced vasoconstriction in isolated rat aorta and renal artery were shown to fit well to the pKI values on cloned alpha 1D- and alpha 1A-AR, respectively. Pretreatment of membrane preparations with sertindole for 30 min significantly reduced the maximal binding capacities. (Bmax) of 125 IBE2254 to the three cloned alpha 1-AR subtypes without alteration of affinities (KD values). In the presence of sertindole, the Bmax of 125IBE2254 binding to the cloned alpha 1-ARs were not significantly changed, while the KD values were significantly increased. Thus, sertindole is a selective irreversible competitive alpha 1-AR antagonist with alpha 1A subtype.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed1997

[Observation on the life habit of Epicata aptera].

Epicata aptera reproduces one generation every year. Adults arise in the last ten-day period of May, mate and lay egg in the first ten-day period of June. They mate and lay egg 1-3 sequence every year, lay egg 108-269 grains every sequence. Period of their laying egg undergoes 48-78 days. Larva have six age period. They take false pupas live through the winter. Complete generations undergo 348-394 days.

Animals↗
PubMed1997

[Biotherapeutic efficacy of adoptive transfer of CD3AK cells in combination with cyclophosphamide and kappa-selenocarrageenan in P 388 leukemic mice].

OBJECTIVE: To study the antileukemia efficacy of a combination of adoptive transfer of CD3AK cells, cyclophosphamide (CTX), and kappa-selenocarrageenan (KSC) in P 388 leukemic mice. METHODS: CD3AK cells in normal DBA/2 murine splenocytes were induced with anti-CD3 antibody and low dose recombinant interleukin-2 (rIL-2). The P 388 murine leukemia model was induced by i.p. injection of P 388 cells into normal DBA/2 mice. The tumor-bearing mice were administrated with adoptively transferred CD3AK Cells and/or CTX and/or KSC. RESULTS: After tumor inoculation, the cellular immune function of P 388-bearing mice was supressed markedly. Adoptive transfer of CD3AK cells with low dose rIL-2 into the P 388 mice significantly enhanced the splenocyte proliferation (SP) induced by Con A, the NK cell activity and the splenocytic IL-2 production and prolonged their survival (45.19%); CTX (200 mg/kg) alone prolonged the survival of P 388-bearing mice (29.90%), but further decreased the immunodeficiency; combination of CTX and CD3AK passive transfer could prevent the reduction of SP, NK activity and IL-2 production in the leukemic mice and prolonged the survival (59.45%), combination of KSC and adoptively transfected CD2AK cells and/or CTX had a much better therapeutic efficacy for P 388 murine leukemia, 12.50%-75.00% of the leukemic mice were cured. CONCLUSION: KSC is a hopeful biological response modifier in cancer biotherapy, and tumor killing effector cells and chemotherapy plus BRM might be a promising candidate for human leukemia biotherapy.

Adoptive Transfer↗
PubMed1997

Induction of ICE and inhibition of c-fos, jun D and zif 268 in 12-month old spontaneously hypertensive rats.

A semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay was used to examine ICE, c-fos, jun D and zif 268 mRNA expression in the aortic and renal artery of 12-month old SHRs and wistar rats. Using this assay system, it was observed that the levels of aortic and renal artery expression of ICE were markedly higher in SHRs than in wistar rats. In contrast, the aortic and renal artery expression of immediate early genes (IEGs), c-fos, jun D and zif 268, were significant lower in SHRs than in wistar rats. Thus, our results suggest that differential regulation of death gene ICE and IEGs such as c-fos, jun D and zif 268 might be involved in the mechanism of pathogenesis of hypertension.

Amino Acid Isomerases↗
PubMed1997

[Expression of nm23/NDPK, integrin, type IV collagenase and uPA in transplanted tumors with various metastatic potential in nude mice and surgical specimens].

OBJECTIVES: To observe the relationship between the metastasis of human lung carcinoma and the expressions of nm23/NDPK, integrins, type IV collagenase and uPA. METHODS: By ABC immunohistochemical staining, we observed the expressions of nm23/NDPK, integrins, type IV collagenase and uPA in four strains of subcutaneous transplanted tumors and 87 surgical specimens for human lung carcinoma. The metastatic potential of four xenografts varied from low to high among PLA-801C, Anip973, PLA-801D, PLA-801DL. The effects of beta 1 antibody and the RGD peptide on the PLA-801DL xenograft were studied in the nude mice. RESULTS: High expression of nm23/NDPK was observed in the four xenografts and specimens from the 87 patients. No association was found between expression of nm23/NDPK and lymph node metastasis. Low expressions of beta 1 subfamily integrins were observed in the four xenografts. beta 1 subunit antibody and RGD peptide had no effect on metastasis of PLA-801DL xenograft. The expressions of type IV collagenase were positively correlated with their metastatic capacity in the four xenografts and surgical specimens from the 87 patients. Anip973 and PLA-801D showed positive staining to uPA, while PLA-801DL and PLA-801C were negative. CONCLUSIONS: The expression of type IV collagenase is positively correlated with the metastatic capacity of lung carcinoma. Although high expression of nm23/NDPK, low expression of integrins, and various expression of uPA were observed, these were not correlated with metastatic capacity of lung carcinoma.

Animals↗
PubMed1997

[Study of the relationship between the control of environmental microorganism and infection of patients with leukemia after trasplantation of bone marrow].

After the transplantation of bone marrow, patients with leukemia are easily infected by kinds of microorganism and die. In this paper, F-mice with the 60Co-gamma irradiation (maximum lethal dose) were transplanted bone marrow, then control the microorganism in the environment. Morever the laminar flow wards for the leukemia patient of bone marrow transplantation were designed according to the data combined with the clinic condition. There is no any infection in twelve patients with bone marrow transplantation from 1989 to 1993.

Animals↗
PubMed1996

Lidocaine in the rostroventromedial medulla and the periaqueductal gray attenuates allodynia in neuropathic rats.

In the present study we attempted to find out if the rostroventromedial medulla (RVM) or the periaqueductal gray (PAG) might contribute to chronic allodynia induced by unilateral ligation of two spinal nerves in the rat. Lidocaine was microinjected in the RVM or PAG and allodynia was quantitatively determined by measuring the hindlimb withdrawal thresholds to mechanical stimulation of the paw. For comparison, lidocaine was also injected systemically (s.c.). Lidocaine in the RVM produced a dose-related (20 and 40 micrograms) antiallodynic effect. Lidocaine (20 micrograms) in the PAG produced identical antiallodynic effect as in the RVM. With systemic administrations of lidocaine, a considerably higher dose (> > 40 micrograms) was needed to produce a significant antiallodynic effect. Naloxone, an opioid-antagonist (1 mg/kg s.c.), did not attenuate the antiallodynic effect of lidocaine in the RVM. An antiallodynic dose of lidocaine (20 micrograms) in the RVM or the PAG did not influence the withdrawal response in the unoperated hindlimb nor the heat-induced tail-flick reflex. The results indicate that the RVM and the PAG have a facilitatory influence on the spinal segmental mechanisms underlying chronic allodynia. The selective attenuation of allodynia induced by lidocaine in the RVM and the PAG is independent of opiate receptors, and it can not be explained by a systemic spread of the drug.

Animals↗
PubMed1996

Wei et al. Reply.

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Journal Article↗
PubMed1996

A transcription map of the major histocompatibility complex (MHC) class I region.

We have applied cDNA hybridization selection to nine YACs spanning 3 Mb of genomic DNA from a region centromeric to HLA-A to the histone cluster that lies telomeric to the human major histocompatibility complex (MHC). In addition to Class I genes and pseudogenes, we describe over 63 genes and 23 additional expressed sequence tags distributed throughout the region. Many of the full-length genes belong to gene families. Prominent among these are a group of genes encoding proteins showing homology to the carboxyl-terminal sequences of butyrophilin and an additional group of zinc finger genes. We also detected several previously undefined genes that are specifically expressed in cells of the immune system, indicating a more complex role of the MHC in the immune response than has been appreciated.

Amino Acid Sequence↗
PubMed1996

The preventive and therapeutic potential of the squalene-containing compound, Roidex, on tumor promotion and regression.

Recent scientific evidence has shown free radicals or reactive oxygen species (ROS) to play an important role in the initiation and progression of cancer. Many radical scavengers have also been found to help reduce the attacks by these ROS. Interestingly, the ROS scavengers that have been investigated are naturally occurring compounds such as vitamins C and E. Roidex is a formulation of squalene, vitamin e, and aloe vera. It was our goal to investigate whether Roidex was able to prevent the development of chemically induced cancer and to cause regression of any tumors already formed in a mouse skin model. In the prevention study, skin tumors were initiated in 50 female CD-1 mice with 7,12-dimethylbenz[a]-anthracene (DMBA) and promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA). The mice were treated with either mineral oil, 5% squalene, or Roidex. At the end of the prevention study, there was a 33.34% incidence to tumors (multiplicity of 1.40) in the mineral oil-treatment group, 26.67% (multiplicity of 0.467) in the 5% squalene and Roidex groups, respectively. The tumor regression study involved the selection of mice with tumors and possible regression of these tumors with Roidex treatment. There was a regression of 33.34% of the tumors in the Roidex-treated group (39 tumors to 26 tumors) compared to the non-treated group whose tumors regressed only 3.44% (29 tumors to 28 tumors).

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1996

Non-NMDA glutamate receptor binding in canine brain after global cerebral ischemia and reperfusion.

We employed a canine model to test the effects of global cerebral ischemia and reperfusion on binding to alpha-amino-3-hydroxy-5-methyl- 4-isoxazole proprionate (AMPA), kainate (KA), and metabotropic glutamate receptors. Ischemia was induced by 10 min of cardiac arrest, followed by restoration of spontaneous circulation for periods of 0, 0.5, 2, 4, and 24 h. Frozen sections were prepared from parietal and temporal cortex, hippocampus, and striatum, and in vitro autoradiography was performed with one of three radioligands: [3H]AMPA, [3H]KA, or [3H] glutamate (using conditions allowing specific labeling of the metabotropic binding site). In striatum, metabotropic binding was unchanged, whereas AMPA and KA binding decreased by 20-30% at 30 min postischemia, remaining depressed through 24 h. In cortex, AMPA and metabotropic binding were decreased at several time-points after ischemia and recirculation, particularly in parietal cortex, whereas KA binding was unaffected in this tissue. Binding to hippocampal regions was largely unchanged, except for a decrease in KA binding at 2 and 4 h postischemia. These findings contrast with results from parallel studies showing increased striatal binding to NMDA receptors following ischemia. Decreased binding to non-NMDA glutamate receptors in striatum and parietal cortex may serve to protect against damage mediated through these receptors.

Animals↗
PubMed1996

Intraoperative use of mitomycin in trabeculectomy.

Mitomycin (0.2 mg/ml) was applied intraoperatively to 26 glaucomatous patients (33 eyes) during conventional trabeculectomy procedure. Most of them were considered to be at high risk of surgical failure. The conjunctival flap was fornix-based in 9 patients (11 eyes). The success rate was 84.8% without any serious side effect.

Female↗
PubMed1996

Dantrolene is cytoprotective in two models of neuronal cell death.

The neuroprotective effects of dantrolene, an inhibitor of calcium release from intracellular stores, were investigated in a model of cell death induced by calcium release from endoplasmic reticulum in vitro. Thapsigargin (50 nM), a selective inhibitor of endoplasmic reticular Ca(2+)-ATPase, significantly increased the cytosolic Ca2+ concentration to 230% over basal levels, induced DNA fragmentation, and reduced cell viability from 94% in control cells to 41% after a 24-h treatment in GT1-7 hypothalamic neurosecretory cells. Pretreatment with dantrolene for 30 min significantly inhibited elevation of cytosolic Ca2+ levels, DNA fragmentation, and GT1-7 cell death induced by thapsigargin in a dose-dependent manner. To determine if dantrolene would also be protective in an in vivo model of neurodegeneration, it was administered intravenously immediately following a 5-min global cerebral ischemia in gerbils, and the number of intact hippocampal CA1 pyramidal neurons was counted 7 days later. The effects of dantrolene on brain and rectal temperature were monitored in a separate experiment. Dantrolene significantly increased the number of intact CA1 pyramidal neurons from 40% (untreated ischemic animals) to 67 (10 mg/kg), 78 (25 mg/kg), or 83% (50 mg/kg) of values in sham controls (all p < 0.001). No significant changes in brain or rectal temperature were detected for 4 h following 50 mg/kg dantrolene. These results suggest that abnormal Ca2+ release from intracellular stores can induce neuronal death and that such a mechanism may contribute to delayed hippocampal neuronal death after cerebral ischemia. Dantrolene may be a potentially useful drug for neuroprotection after cerebral ischemia.

Animals↗
PubMed1996

Effect of dietary genistein on antioxidant enzyme activities in SENCAR mice.

Dietary administration of the soybean isoflavone genistein (50 and 250 ppm) for 30 days significantly increases the activities of antioxidant enzymes in various organs of SENCAR mice. Feeding a 250-ppm genistein diet to SENCAR mice significantly increases the activities of catalase in small intestine, liver, and kidney, the activities of superoxide dismutase and glutathione peroxidase in skin, and the activity of glutathione reductase in skin and small intestine. Feeding 50 ppm genistein to SENCAR mice results in elevated catalase activity in the small intestine and increases glutathione-S-transferase activities in skin, small intestine, liver, kidney, and lung. Dietary genistein's greatest enhancement of antioxidant enzyme activities occurred in skin and small intestine. Our results suggest that dietary genistein enhances the activities of antioxidant enzymes in various organs, which may be a mechanism(s) of genistein's chemopreventive action.

Animals↗