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Biomedical subjects

L Yang

Publications and source records attributed to L Yang.

At least 379 records · Page 21Linked to original sources
PubMed1999

[An analysis of the therapeutic effects and reactions in treating acute promyelocytic leukemia with intravenous arsenic trioxide or all-trans retinoic acid].

OBJECTIVE: To compare the therapeutic effects and reactions of intra venous arsenic trioxide and all-trans retinoic acid in treating patients with acute promyelocytic leukemia (APL). METHODS: 75 cases of APL were randomized either to arsenic trioxide (37) or to all-trans retinoic acid (38). The rates of complete remission (CR), disease free survival (DFS) and side effects were observed. RESULTS: In the two groups of patients with APL, the rate of CR was 86.4% and 84.2%. There was also no significant difference in the rate of DSF phase of CR (P > 0.05). The side effects of these two medications in therapeutic dose were mild and there was no cross resistance between them. CONCLUSION: Arsenic trioxide can lead to apoptosis of leukemic cells and might be a new promising drug to induce differentiation.

Adolescent↗
PubMed1999

[The percentage of free prostate specific antigen used in detecting prostate cancer].

OBJECTIVE: To evaluate the value of the percentage of free prostate specific antigen in detecting prostate cancer. METHODS: Serum free prostate specific antigen (F-PSA) and total PSA were measured with immunoradiometric assay, and the free/total PSA ratio was calculated. In 117 patients, 31 had prostate carcinoma and 86 BPH. RESULTS: The free/total PSA ratio was lower in patients with prostate cancer than in those with BPH. If the total serum PSA level was limited with in 4 - 10 ng/ml, the free/total PSA ratio can be used in the differential diagnosis of prostate cancer and BPH except total PSA. CONCLUSIONS: The free/total PSA ratio can be used in the differential diagnosis of prostate cancer and BPH, especially when serum PSA level is limited with in 4 - 10 ng/ml.

Aged↗
PubMed1999

[Significance of expression of epidermal growth factor receptor, transforming growth factor beta, c-erbB-2 oncogene in myoepithelioma of salivary gland].

OBJECTIVE: To explore the effect of expression of epidermal growth factor receptor (EGFR), transforming growth factor beta (TGF beta), c-erbB-2 oncogene in myoepithelioma and malignant myoepithelioma. METHODS: 20 cases of myoepithelioma and 20 cases of malignant myoepithelioma were examined by immunohistochemical methods. RESULTS: All cases showed overexpression of EGFR and TGF beta, the intensity of expression didn't associate with the benignity and malignity of tumors. The overexpression of c-erbB-2 oncoprotein was seen in 5 cases of myoepithelioma and 13 cases of malignant myoepithelioma, and the cases of malignant myoepithelioma were stained more intense than that of myoepithelioma. CONCLUSION: The synergy of EGFR and TGFR beta had significant relation to the proliferative and differentiation processes of myoepithelial tumor. The activated c-erbB-2 oncogene, that is similar with EGFR in structure, plays an important promoting role in unrestricted progression of malignant myoepithelioma cells.

Biomarkers, Tumor↗
PubMed1999

[Effects of human BMP2 gene transfection on NIH3T3 cells in vitro].

OBJECTIVE: To elucidate the mechanism of bone morphogenetic protein (BMP) on cell differentiation and to provide basis for BMP gene therapy. METHODS: A phagemid expression vector for human BMP2 (pBK-B2) was constructed and transfected into the NIH3T3 cells by using Lipofect AMINE. Positive cell clones were selected with G-418. The stable transfection, expression and secretion of hBMP2 were determined by in situ hybridization, immunohistochemistry and sandwich-in ELISA methods. The proliferativity of the transfected cells were assayed by methabenzthiazuron (MTT) method. Alkaline phosphatase (ALP) and osteocalcin (OC) production were also measured in the transfected cells. RESULTS: The results showed that cell proliferation was inhibited after the transfection with hBMP2 gene. But the transfected cells showed increased ALP activity and OC production. CONCLUSION: These results indicate that BMP2 is expressed stably and efficiently in the NIH3T3 cells and is involved in inducing differentiation of NIH3T3 cells into osteoblast-like cells.

3T3 Cells↗
PubMed1999

[Pathomorphological and amyloid beta-protein immunohistochemical findings in autopsied brains of Alzheimer's disease].

OBJECTIVE: To study the incidence and neuropathological features of Alzheimer's disease in Chinese and the significance of silver and amyloid beta-protein staining for the pathological diagnosis of Alzheimer's disease. METHODS: Among 445 autopsy cases above 60 years in age (including 60) collected from 1982-1998 in the Department of Pathology, Beijing Hospital, totally 29 cases were diagnosed as Alzheimer's disease pathologically (6.5%), accompanying with a history of mental deterioration and the histological changes in certain areas of the brain fulfilling the Khachaturian or Mirra criteria. Tissue blocks were taken from 6 standard regions of the brains for Bodian, Bielschowsky and amyloid beta-protein immunostaining. Senile plaques and neurofibrillary tangles were quantified. RESULTS: Four main types of senile plaques were noticed and the result by amyloid beta-protein immunostaining was considered more sensitive than that of the silver impregnation staining. The former one enabled to demonstrate all the 4 types of senile plaques, while silver impregnation staining could only demonstrate clearly the primitive and neuritic plaques, but not the small diffuse and burn-out plaques. The senile plaques were noticed to be focused in the hippocampus, superior temporal gyrus and middle frontal gyrus while the neurofibrillary tangles, were mainly obtained in the hippocampus, temporal cortex and amygdaloid. Cerebral amyloid angiopathy was found in 25 out of 29 Alzheimer's disease cases. CONCLUSIONS: Alzheimer's disease may be the main cause of dementia among the elders in Chinese and immunostaining for amyloid beta-protein pretreated with formic acid may set a high value on the pathological diagnosis of Alzheimer's disease.

Aged↗
PubMed1999

[Repair of soft tissue defect of heel with myocutaneous flap of flexor digitorum brevis].

OBJECTIVE: To investigate the repairing method of soft tissue defect of heel, pedicled island myocutaneous flap of flexor digitorum brevis was designed. METHODS: From 1984 to 1997, 26 cases with soft tissue defect of heel were adopted in the clinical trial. Among them, the were 18 males, 8 females and the age ranged from 15 to 60 years old. The area of wound ranged from 2.5 cm x 1.5 cm to 8.0 cm x 6.0 cm. RESULTS: After operation, all of the flaps survived. They were followed up for 9 to 72 months. All of the flaps had primary healing except in one there was infection of peripheral of the flap. The contour of heel was satisfactory the sensation of flap was good and the weight-bearing function was also successful. CONCLUSION: It was concluded that the myocutaneous flap of flexor digitorum brevis could be used to repair the soft tissue defect of heel because of its nearby position, hidden location, good recovery of skin sensation and weight-bearing function, Besides, the procedure of this operation was simple and the anti-inflammatory potential of the flap was high. However, Because of the limited donor area, the pre-operative design was important.

Adolescent↗
PubMed1999

[Application of skin-stretching devices in reparative and reconstructive surgery].

OBJECTIVE: To testify the availability and the clinical efficacy of the skin-stretching device. METHODS: The skin-stretching device designed by ZHOU Li-an, which was used in the treatment of the granulation wound, the donor site of flap, and the skin defect after the excision of tumor by skin traction technique at the wound edges. RESULTS: The usage time of skin-stretching device was 15-720 minutes, it could be used preoperatively, intraoperatively and postoperatively. Followed up 16 cases for 6 to 12 months, the device was effective. CONCLUSION: The skin stretching device is practical and effective in wound closure of skin defect.

Adolescent↗
PubMed1999

[Role of sera from peptic ulcer patients in cell proliferation of human gastric carcinoma].

This study aimed at the relationship of helicobacter pylori infection to gastric carcinoma pathogenesis. Forty-nine serum samples from patients with gastric and duodenal ulcer and 20 serum sample from normal subjects were collected for the assessment of serum gastrin by radioimmunoassay (RIA) and serum IgG, IgA and IgM antibodies against H. pylori by ELISA respectively. The patients, serum samples were divided into four groups for observations on whether the sera would affect the cell proliferation of HAC803 derived from human gastric carcinoma and of HT29 from human colonic carcinoma cultured in vitro. The cell proliferation was determined by MIT assay. The results showed that the level of serogastrin in gastric and duodenal ulcer was significantly higher than that in normal control (139.6 +/- 38.17 pg/ml vs 63.12 +/- 28.7 pg/ml, P < 0.01). As for the sera of ulcer subjects, the highest anti-HpIgG group (group A) and the highest anti-Hp IgA group (group B) displayed a significantly enhanced cell proliferation of human gastric carcinoma (P < 0.05), especially group B. But all the four groups had less significant increase in cell proliferation of human colonic carcinoma (P > 0.05). These findings indicate that, in the highest anti-HpIgG group and the highest IgA group of the peptic ulcer subjects infected by H. pylori, the sera can enhance cell proliferation of gastric carcinoma, however the role is less associated with serum gastrin.

Antibodies, Bacterial↗
PubMed1999

[Effects of TGF beta on BMP-2 gene transfection cells in vitro].

OBJECTIVE: To elucidate the mechanism of bone morphogenetic protein-2(BMP-2) and transforming growth factor beta(TGF beta) on cell differentiation. METHODS: A phagemid expression vector for human BMP-2 (pBK-B2) was constructed and transfected into the NIH3T3 cells by using lipofectamine. Positive cell clones were selected with G418. The stable transfection and expression of BMP-2 were determined by using in situ hybridization and immunohistochemistry methods. The proliferativity of the transfected cells treated with TGF beta were assayed by MTT method. Alkaline phosphatase (ALP) and osteocalcin (OC) production were also measured. RESULTS: The proliferation of the transfected cells was stimulated after being treated with TGF beta (50 ng/ml). But the ALP activity and OC production were inhibited. CONCLUSION: The effects of TGF beta are closely related to many factors, and BMP and TGF beta may be synergistic in cell proliferation and differentiation.

3T3 Cells↗
PubMed1999

[Protein A tangential flow membrane chromatographic column used for immunoadsorption therapy].

Tangential flow membrane chromatographic column is a new model of immunoadsorption therapy from blood. The results showed that the structure of the column and the flowing channel had a little damages for blood cells. The relation of flow-rate and backpressure with water, plasma and blood individually as the fluid flowing through the column has been studied. It was observed that backpressures increased with fluid viscosity, when flow-rate of blood was 120 mL/min and the backpressure reached 0.093 MPa; The adsorption capacity of protein A of the column for IgG from human plasma has been measured. When plasma and blood individually circulated through the column for 1 h, the column with 139 mg protein A immobilized on the matrix (6 mg protein A/g dry matrix) adsorbed 553 mg IgG (23.8 mg IgG/g dry matrix) from human plasma and 499.4 mg IgG (21.5 mg IgG/g dry matrix) from human blood respectively. The circulation time had a great influence on IgG adsorption capacity; but the circulation rate had a little influence on IgG adsorption capacity. The result of extracoporeal blood perfusion for dog showed that the Protein A column has good blood biocompatibility.

Chromatography↗
PubMed1999

[Hydrophobic membrane chromatography for fast purification of biological macromolecules].

Cellulose membrane bonded with four commonly used hydrophobic groups, octyl, butyl, phenyl and polyethylene glycol was first investigated for their binding and purification characteristics of protein and enzyme with octyl- and phenyl-Sepharose CL-4 B as controls. Hydrophobic membranes bound BSA effectively by hydrophobic interaction in high salt solution. Their binding capacities were not notably affected by significantly increasing the flow mass rate or decreasing the mass concentration of protein solution, but were much lower than those of octyl- and phenyl-Sepharose CL-4B. 11.8 fold of purification with an approximately 100% recovery of bovine liver catalase was achieved by step gradient elution on the phenyl cellulose membrane cartridge in a single step in only ten mins or a little more. Increase of the flow mass rate had no effect on the purification of catalase, however, the processing time was shortened greatly. Hydrophobic membrane chromatography here reported exibits a potential of fast processing of the protein solution in large volume with low mass concentration of the target protein, such as genetic engineering culture solution.

Animals↗
PubMed1999

[Autoantibodies to the heterogeneous nuclear ribonucleoproteins and the autoimmune diseases].

Autoantibodies to the heterogeneous nuclear ribonucleoproteins (hnRNP) have a great role in the diagnosis of rheumatic diseases. hnRNP-A/B proteins are the main autoantigens in Rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and mixed connective tissue disease (MCTD). Anti-RA33 autoantibodies which target the hnRNP proteins A2, B1, B2 (the 'RA33 complex') help to the diagnosis of RA at early stage. Therefore, anti-hnRNP autoantibodies are not only valuable diagnostic markers but may also allow deep insights into the pathogenetic mechanisms of rheumatic diseases.

Arthritis, Rheumatoid↗
PubMed1999

[Construction of a pufferfish gridded cosmid library].

OBJECTIVE: Pufferfish is a newly-established model organism in human genome research, which has been demonstrated its unique advantages in comparative genomics. Construction of a genomic library of pufferfish is the prerequisite to any studies of its genome. METHODS: Genomic DNA from Fugu rubripes, a species distribute only in Japan and China seas, was used to construct a library in a novel cosmid vector, named sCOGH2, which contains an exon-trapping cassette. RESULTS: This library is composed of 57,600 clones gridded in 60,096-well cell culture plates, one clone each well. The average size of the inserts is around 35 kb. It provides 99.2% probability to find any unique DNA fragment of pufferfish in this library. The clones of this library can survive after more than 10 times freeze-thaw, also demonstrating high stability in propagation. The clones shone highly positive signals when hybridized with the pufferfish genomic DNA. CONCLUSIONS: The library accords with qualitative demands of a cosmid library.

Animals↗
PubMed1999

[Analysis of HLA-DRB1 allele polymorphism for patients with allergic rhinitis].

OBJECTIVE: To analyze the association between allergic rhinitis and HLA-DRB1 in northeast area of China. METHODS: Using polymerase chain reaction/sequence specific primers (PCR/SSP) technique, we studied distributive speciality of HLA-DRB1 alleles in 35 patients with (AR) and 94 healthy controls. RESULTS: The statistical results showed that the frequencies of DRB1 * 0101.2 and DRB1 * 0302 alleles were significantly higher in AR patients than in those of controls. The frequencies of DRB1 * 0101,2 and DRB1 * 0302 were 12.86% (relative risk = 15.92 Pc < 0.0004) and 5.71% (relative risk = 12.00, Pc < 0.05) respectively, the other gene frequencies bore no significant difference. CONCLUSION: AR was associated with HLA-DRB1 * 0101.2 and DRB1 * 0302 alleles.

Adult↗
PubMed1999

[Removal of a broken needle in the left pterygoid fossa:report of one case]

OBJECTIVE:To research the application of orthodontic techniques of edgewise brackets to enhance the curative effect of stabilizing the loose teeth.METHODS: Between 1993-1998,we applied orthodontic techniques of Edgewise brackets to treat 35 cases of patients which include 58 loosen teeth caused by trauma factors,most adopting edgewise brackets plus round wire.RESULTS: We have obtained excellent curative effect in 45 teeth,good curative effect in 9 teeth,and 4 teeth failed.CONCLUSION: Orthodontic technique of Edgewidw brackets is a reliable method to stabilize the loose teeth.Compared with conventional arch bar splint fixation,the Edgewise technique has its unique advantage.

Journal Article↗
PubMed1999

[A comparison of Fe, Zn, Cu, Cr, Cd and Pb concentration in serum determined by ICP-AES using different sample preparation procedures].

Fe, Zn, Cu, Cr, Cd and Pb concentrations in serum of 21 arteriosclerosis (AS) and 18 healthy control (CK) were determined by ICP-AES, and sample solution was prepared using acid digestion (Dig.) and acid dilution (Dil.) procedure. Serum total Fe, Zn and Cr were significantly higher using Dig. than that using Dil. Serum Cu and Pb were of no significant differences using the both procedures. Serum Cd was significantly lower using Dig. than that using Dil. The results of Fe, Cu, Zn and Cr were positively correlated between Dig. and Dil., but those of Pb and Cd were of no significant correlation. Six elements concentrations in serum determined were significantly different between AS and CK using Dig. The digestion procedure was recommended for serum trace elements analysis using ICP-AES.

Case-Control Studies↗