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W Cui

Publications and source records attributed to W Cui.

At least 91 records · Page 5Linked to original sources
PubMed1995

Concerted action of TGF-beta 1 and its type II receptor in control of epidermal homeostasis in transgenic mice.

Transforming growth factor-beta 1 (TGF-beta 1) is a modulator of cellular proliferation, differentiation, and extracellular matrix deposition. It is a potent epithelial growth inhibitor and can alter the differentiative properties of keratinocytes, in vitro, but little is known about its normal physiological function in the epidermis in vivo. Transgenic mice were generated using a keratin 10 (K10) gene promoter to drive constitutive expression of TGF-beta 1 in the suprabasal keratinocyte compartment. Surprisingly, these mice showed a two- to threefold increase in epidermal DNA labeling index over control mice, in the absence of hyperplasia. The transgene, however, acted in the expected fashion, as a negative regulator of cell growth, when hyperplasia was induced by treatment by 12-tetradecanoyl-phorbol-13-acetate (TPA). Epidermal TGF-beta type I and II receptor (T beta RI and T beta RII) levels were examined in control and transgenic mice during induction of hyperplasia by TPA. Whereas T beta RI levels remained relatively constant, T beta RII expression was strongly induced in TPA-treated skins, prior to the induction of the growth inhibitory response to TGF-beta 1, and its level of expression correlated with growth sensitivity to TGF-beta 1 in vivo and in vitro. These results suggest that TGF-beta 1 and its type II receptor are part of the endogenous homeostatic regulatory machinery of the epidermis.

Activin Receptors, Type I↗
PubMed1995

A practical procedure for the cryopreservation of marrow cells intended for autotransplantation.

A simple and practical method of unfractionated bone marrow processing and cryopreservation was studied. The date shows that RBCs can be rapidly sedimented by methylcellulose or sodium carboxymethyl starch within 15-45 min. The cells can be cryopreserved in a mixture consisting of 5% DMSO, 6% HES and 4% Albumin prepared in a Lactated Ringer solution which is widely used, and can be simply immersed into a -80 degrees C freezer and stored in liquid nitrogen until infusion. Recovery percentages of nucleated cell, cell viability and CFU-G were similar to those cryopreserved with the conventional method. Clinical toxicity was mild in 12 infused patients. Of them 8 patients had received high dose chemotherapy +/- TBI and their peripheral WBC recovery was rapid. The recovery of WBC or Platelet (PLT) in the study group was similar to that of the control group whose marrow cells were cryopreserved in 10% DMSO. Therefore, cells cryopreserved with this method can also accelerate the hematopoietic recovery in myeloablatively treated patients.

Adolescent↗
PubMed1995

[Mutation of P53 gene in a highly metastatic human lung cancer cell line].

PG cell line, derived from a lung giant cell carcinoma, has the characteristics of rapid growth and high tumorigenicity. When transplanted to nude mice, spontanious metastasis to lung and lymphnode is high in frequency and stable. To understand the molecular basis of PG's biological behaviors, expression of tumor suppressor gene p53 was studied. It was found that expression of p53 protein was increased as demonstrated by immunohistochemical stainning. A change in polymorphsim in exon 7 of p53 gene was detected by nonisotopic PCR-SSCP, suggesting a change in base composition. Thermal cycling sequencing of both strands of exon 7 demonstrated a transversion of CGG to CTT at codon 248. Similar study with the same methods on Ki-ras oncogene was done, but no mutation was found. The relationship between p53 gene mutation and the metastatic potential of PG cells needs further exploration.

Animals↗
PubMed1995

A simple method for the transformation of Agrobacterium tumefaciens by foreign DNA.

A method for successful introduction of Ti plasmid vector ( > 10 kb) into Agrobacterium tumefaciens is described. Competent A.tumefaciens cells were prepared with 50 mmol/L CaC1(2) at room temperature and introduction was done on ice followed by a 28 degrees C heat pulse. The efficiency of transformation was 10(-4)-10(-5) transformants per total recipient population or 10(6) transformants per microgram DNA. The effects of growth phase of A. tumefaciens cells, concentration of CaC1(2) solution, temperature, liquid N2, heat pulse, recovery time, and storage time of competent cells at 4 degrees C or -20 degrees C (in 15% glycerin) on transformation were studied.

Agrobacterium tumefaciens↗
PubMed1994

Lack of transforming growth factor-beta 1 expression in benign skin tumors of p53null mice is prognostic for a high risk of malignant conversion.

Expression of transforming growth factor beta 1 (TGF beta 1) protein was examined in chemically induced benign skin tumors with genetically defined empirical risks for malignant conversion. Benign tumors induced in mice which have both alleles of the p53 gene deleted have a malignant conversion frequency of approximately 50%, whereas similar tumors induced in wildtype and heterozygous p53 mice have conversion probabilities of 3 and 8%, respectively (Kemp et al., Cell, 74: 813-822, 1993). The TGF beta 1 antibody, anti-CC (1-30-1), was shown to stain either the proliferative keratinocyte compartment of the tumor or the tumor stroma, whereas another TGF beta 1 antibody, anti-LC (1-30-1), stained highly differentiated granular cells of the tumors. A strong correlation was found between staining of the proliferative keratinocyte compartment of tumors with the anti-CC (1-30-1) antibody and tumor genotype. Only 18% (6 of 32) of homozygous p53 null tumors showed any basal keratinocyte staining with this antibody, whereas over 80% (32 of 38) of heterozygous and wild-type tumors showed positive staining. Additionally, in most tumors examined, the spatial distribution of staining for the proliferating cell nuclear antigen appeared to be mutually exclusive with that of TGF beta 1 on adjacent serial sections. This suggests that, in these cases, tumor keratinocytes are sensitive to negative growth regulation by TGF beta. TGF beta 1 protein staining in benign tumors is thus prognostic for a low probability of malignant conversion, and its expression may be mechanistically involved in limiting malignant conversion since, at the benign tumor stage examined, keratinocytes are still sensitive to growth inhibition by TGF beta 1.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Characterization of the promoter region of the membrane cofactor protein (CD46) gene of the human complement system and comparison to a membrane cofactor protein-like genetic element.

Membrane cofactor protein (MCP; CD46) is a widely expressed C regulatory protein that inhibits C activation on self-tissue. MCP binds C3b and C4b deposited on autologous cells and then serves as a cofactor for their inactivation by limited proteolytic cleavage. To characterize the DNA sequence elements responsible for controlling MCP expression, the 5' flanking region of the human MCP gene was cloned. Sequencing of 1350 nucleotides upstream from the ATG codon revealed a GC-rich region in the initial 500 nucleotides that is especially rich in the CpG dinucleotide. A CAAT box in reverse orientation, surrounded by four putative SP1 binding sites but lacking a typical TATA element, was within the first 200 nucleotides of this GC-rich region. The major transcriptional initiation site for HeLa cells, determined by primer extension and S1 nuclease protection analyses, was located 105 nucleotides from the translational start site. This overall orientation of the promoter region is characteristic of "housekeeping" genes. The MCP promoter region was further examined in HEp-2 cells by the chloramphenicol acetyltransferase (CAT) reporter gene assay, using various constructs derived from the 5' region of the MCP gene. The MCP promoter activity was confined to the GC-rich region from -624 to +96 (start site of transcription being +1). Inclusion of an AT-rich sequence from -624 to -1204 resulted in a 42% reduction in CAT activity suggesting that an inhibitor is present among the AT-rich sequences. The 5' flanking region of a highly homologous partial duplication of the MCP gene was also cloned and sequenced, and various constructs were assessed in the CAT reporter system. Many of the functionally relevant sequences seen in MCP are also found in the MCP-like 5' UT region, which is 85% homologous to MCP. The most striking difference was a 224 nucleotide deletion that was upstream from the corresponding MCP region harboring most of the promoter activity. Although expression of an MCP-like protein has not been reported, the MCP-like promoter region produced promoter activity comparable with that of MCP. These results serve as a basis for subsequent analyses of the expression of MCP in various cells and tissues and for understanding the mechanism of its modulation in inflammatory conditions. Also, through a comparison of the 5' region of MCP with other genes in the regulators of C activation gene cluster (at 1 q32), we propose a model for the evolution of the promoters in this tight linkage group.(ABSTRACT TRUNCATED AT 400 WORDS)

Antigens, CD↗
PubMed1993

[Blepharoplasty and oculocardiac reflex].

100 patients have undergone electrocardiograph before and during blepharoplasty and after anaesthesia. The results show that the positive rate of oculocardiac reflex is 65%. The mechanism of occurrence of oculocardiac reflex is analysed. It has also been pointed out that great attention should be paid to the phenomenon and appropriate measures should be taken to prevent the occurrence of oculocardiac reflex.

Adult↗
PubMed1991

Restriction enzyme analysis of mitochondrial DNA in colorectal tumours.

Total cellular DNA samples were isolated from 15 colorectal adenocarcinomas, 8 colon adenomas and their adjacent histologically normal colon mucosa. These DNA samples were digested separately with 13 different restriction endonucleases and analysed by Southern blot hybridization using a purified 32P-labelled human mtDNA probe. The fragment patterns from tumour mtDNA were compared to those from corresponding normal mtDNA. No evidence for large deletions, insertions, rearrangements or single base mutations in the detectable regions was detected. This suggests that other mechanisms may be responsible for the changes of colorectal tumour mitochondria.

Adenocarcinoma↗
PubMed1990

[Studies on the composition and stability constant of inclusion complexes of beta-cyclodextrin with fluorouracil and ftorafur by NMR].

The composition and stability constants of the host-guest inclusion complexes of beta-cyclodextrin (beta-CD) with fluorouracil (5-Fu) and ftorafur (FT-207) were studied by 19F NMR. The 19F chemical shift changes (delta) of 5-Fu and FT-207 on complexation with beta-CD were used to determine the stoichiometry of these inclusion complexes by Job plot. It was shown that both 5-Fu and FT-207 formed 1:1 inclusion complexes with beta-CD. The stability constants (Kc) of their complexes. with beta-CD, calculated from the slope of linear relation between delta/CCD0 and delta(CCD0 being the initial concentration of beta-CD) were found to be 17.0 +/- 1.7 mol-1.L and 9.0 +/- 0.1 mol-1.L at 40 degrees C respectively. The 19F chemical shifts of these complexes relative to their free forms were also obtained and discussed in terms of the structures of these beta-CD inclusion complexes in aqueous solution.

Cyclodextrins↗
PubMed1989

[Right ventricular volumes and ejection fraction estimated by two-dimensional echocardiography].

UNLABELLED: The right ventricular volumes and ejection fraction (RVEF) obtained from two-dimensional echocardiography and from right ventricular angiography were compared in 20 patients with congenital heart disease. Single plane area-length method of apical four-chamber view was used to estimate echocardiographic right ventricular volumes and single plane right anterior oblique projection was used to calculate angiographic right ventricular volumes. The results showed that right ventricular volumes estimated by echocardiography correlated highly with that calculated by angiography, the correlation coefficients of end-diastolic volume, end-systolic volume and stroke volume were 0.983, 0.976, 0.973 respectively. Echocardiographic RVEF also correlated strongly with angiographic RVEF (r = 0.992, P less than 0.001), and there were no significant difference between the two methods (P greater than 0.05). CONCLUSION: two-dimensional echocardiography can be used to accurately estimate right ventricular volumes and ejection fraction.

Adolescent↗
PubMed1988

Distribution of membrane cofactor protein of complement on human peripheral blood cells. An altered form is found on granulocytes.

Membrane cofactor protein (MCP) of human complement is an iC3/C3b-binding glycoprotein with a characteristic two-band (63 kDa and 55 kDa) pattern on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Using affinity chromatography, it has been found on human mononuclear cells and platelets. MCP has been purified and shown to be a cofactor for the I-mediated cleavage of C3b. A rabbit polyclonal antibody was produced to the purified protein and this reagent employed to analyze the distribution of MCP on human peripheral blood cells. Flow cytometric analysis indicated that MCP is unimodally present on all platelets, granulocytes, T helper lymphocytes, T suppressor/cytotoxic lymphocytes, B lymphocytes, natural killer cells and monocytes but not erythrocytes. The presence of MCP on granulocytes was unexpected. To evaluate this, MCP was isolated by immunoprecipitation and analyzed by SDS-PAGE followed by autoradiography. The Mr of granulocyte MCP was that of a single broad band in which the typical two-band pattern could not be distinguished. Alterations in the conditions of the affinity column procedure increased the efficiency of the isolation of monocyte MCP and led to the reproducible isolation of granulocyte MCP. These results indicate that MCP of granulocytes has both structural and functional differences compared to MCP of plateletes and mononuclear cells. The wide distribution of MCP among peripheral blood cells supports the concept that MCP is important in the protection of host cells from complement-mediated damage.

Antigens, CD↗
PubMed1986

[Photodynamic therapy (PDT) of bladder cancer in the rat].

PDT of rat bladder cancer, induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) was studied. All animals were divided at random into three groups. Group 2 and 3 were treated by hematoporphyrin derivative (HPD)-laser PDT while group 1, without treatment, served as control. The results showed that the malignant lesions could be selectively and obviously destroyed, if the whole tumor area were sufficiently exposed to the laser irradiation. However, the normal bladder epithelium and muscle layer showed no histologic change. Similar reactions were found in papilloma of bladder which was considered as precancerous lesion. Thus, PDT may be beneficial to cancer prevention. Its role in prevention and treatment of bladder cancer should be further studied experimentally and clinically.

Animals↗
PubMedDate not supplied

Modified subcutaneous tissue with neovascularization is useful as the site for pancreatic islet transplantation.

The success rate of subcutaneous transplantation of pancreatic islets has been extremely low. Insufficient oxygen supply to the grafted islets is one possible major obstacle to the preservation of graft function. This study attempted to use basic fibroblast growth factor (bFGF) in subcutaneous transplantation to induce neovascularization and a sufficient blood flow around the space formed for grafted islets in the subcutaneous tissues. A bFGF-releasing device was designed enclosing bFGF in a polyethylene terephthalate mesh bag coated with polyvinylalcohol hydrogel. In the vascularized group (n = 5), two bFGF-releasing devices were implanted bilaterally into the subcutaneous tissue of the back of streptozotocin-induced diabetic Lewis rats. One week after implantation, isolated rat islets (5000) were syngeneically transplanted subcutaneously after the removal of the devices. In the control group (n = 5), no devices were implanted and the same number of rat islets was transplanted directly. One week after the implantation of the devices into the test animals, a thick, well-vascularized capsule was observed in the subcutaneous site. All vascularized recipient rats showed significant decreases in nonfasting blood glucose and maintained normoglycemia for more than 1 month after islet transplantation. However, in the control group, all rats failed to achieve normoglycemia after transplantation. This study provides evidence that the subcutaneous tissue is a promising site for pancreatic islet transplantation, offering convincing advantages in acceptability for diabetic recipients. Establishment of this subcutaneous islet transplantation technique will afford some new perspectives on successful clinical islet transplantation.

Animals↗