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Y Dong

Publications and source records attributed to Y Dong.

At least 289 records · Page 16Linked to original sources
PubMed1991

HML-1 antigen on mucosa-associated T cells, activated cells, and hairy leukemic cells is a new integrin containing the beta 7 subunit.

The monoclonal antibodies HML-1, B-ly7 and Ber-ACT8 recognize intramucosal gut T lymphocytes, activated cells, and hairy cell leukemia. The antigen on hairy cells consists of three glycoproteins (160 kappa D, 130 kappa D and 105 kappa D unreduced; 145 kappa D and 120 kappa D reduced). These peptides have biochemical features reminiscent of integrins but we have shown by immunoprecipitation that they are not known integrin subunits. We have used a newly produced antibody (BP6) to purify this molecule and shown by N-terminal sequence analysis that the smallest subunit is the product of integrin beta 7 cDNA. This molecule is thus a new member of the integrin family of leucocyte adhesion proteins. Immunoprecipitation experiments indicate that the two larger subunits are recognized by HML-1, B-ly7 and Ber-ACT8.

Amino Acid Sequence↗
PubMed1991

Anti-PPD antibodies in Chinese Behçet's disease.

Anti-PPD antibody determinations were carried out by the ELISA method using extracted PPD of tubercle bacillus H37RV as the target antigen. The positive rates of anti-PPD antibodies in patients with active tuberculosis, inactive tuberculosis, Behçet's disease, or non-tubercular disease and in a village population were 97.5%, 77.4%, 48.9%, 33.6% and 13.9%, respectively. Although the average titer of anti-PPD antibodies in Behçet's disease was lower (2.168 +/- 0.854) than that in active tuberculosis (3.126 +/- 1.182), it was about the same as that in inactive tuberculosis (2.336 +/- 1.250). In comparison with the village community population surveyed, the average titer of anti-PPD antibodies in Behçet's disease patients was distinctly higher (P less than 0.001). These results indicate that tuberculosis may be etiologically related to Behçet's disease.

Antibodies, Bacterial↗
PubMed1991

[The amount of IgG synthesized within the central nervous system in patients with multiple sclerosis].

IgG-Alb ratio, IgG index and IgG synthesis rate were determined in 40 patients with multiple sclerosis (MS group), 20 patients with other neurologic diseases (OND group) and 22 normal persons (normal group) by using Beckman Immunochemistry System II. The results showed the average values and abnormal frequencies of the three parameters in MS group were significantly higher than those in the normal group and OND group (P less than 0.01), indicating the synthesis of IgG within the central nervous system (CNS) in MS. These parameters were increased in most of the MS patients. Therefore, they could be used in the diagnosis of MS. It was also found that the amount of IgG synthesized within CNS was decreased in patients treated with corticosteroids.

Adolescent↗
PubMed1991

[Long-term culture and a morphological study of endothelial cells from human aorta].

Endothelial cells from human aorta were successfully cultured first in this Lab in our country. Cells survived and passed through 10-15 generations. Long term cultured endothelial cells from human aorta were observed under phase-contrast microscope, scanning, transmission electron microscope, and investigated immunocytochemically by immunofluorescence of specific antibody against Factor-VIII related surface antigen, and ABC method using monoclonal antibody 9B9 against human angiotensin-converting enzyme. Medium RPMI-1640 supplemented with 20% human serum, endothelial cell growth factor 200 micrograms/ml, heparin 100 micrograms/ml and gelatin coated flasks were very important conditions for long term culture of human endothelial cell.

Aorta↗
PubMed1991

The 1958 and 1987 ARA revised criteria for rheumatoid arthritis in Chinese patients. A comparative study.

The American Rheumatism Association (ARA) 1958 and 1987 criteria for the classification of rheumatoid arthritis (RA) were applied to 111 consecutive RA patients and 54 patients with non-RA connective tissue diseases from three hospitals of tertiary level in Beijing. Comparison of the two criteria showed that the specificity was the same, being 88% for both, whereas the sensitivity varied from 94% of the 1958 criteria to 91% of the 1987 criteria. Factors affecting the sensitivity were morning stiffness for more than one hour and increase of number of swollen joints from one to three in the 1987 revised criteria.

Adolescent↗
PubMed1990

A hormone response element upstream from the human alcohol dehydrogenase gene ADH2 consists of three tandem glucocorticoid receptor binding sites.

The 5'-flanking region of the human gene encoding beta-alcohol dehydrogenase (ADH2) was shown by DNase I footprinting to contain three tandem binding sites for purified glucocorticoid receptor. The three binding sites lie very close together between nucleotide (nt) positions -245 and -171 with respect to the transcription start point. DNase I footprinting using a rat liver nuclear extract indicated a lack of protection of the glucocorticoid receptor binding sites, but protection of a sequence between nt -209 and -191 which partially overlaps the glucocorticoid receptor binding sites I and II. This site has homology with the known binding site for hepatocyte nuclear factor 1 (HNF1). ADH2 promoter DNA fragments containing various lengths of 5'-flanking sequences were fused upstream from the gene encoding chloramphenicol acetyltransferase (cat) and transfected into the HepG2 human hepatoma cell line. The resulting cat expression was subject to induction by dexamethasone in constructions containing ADH2 DNA between nt -272 and -171. This indicates that the glucocorticoid receptor binding sites identified by footprint analysis function as a glucocorticoid response element (GRE) in a liver cell line. Heterologous ADH-cat fusions, in which the ADH2-GRE was fused to the adenovirus major late promoter, exhibited glucocorticoid induction of cat expression in CV-1B cells when cotransfected with a glucocorticoid receptor expression vector. Glucocorticoid regulation in CV-1B was observed when either all three glucocorticoid receptor binding sites (sites 0, I, II) or the two distal sites (sites 0, I) were present. Overall, these results indicate that the ADH2 gene possesses a functional GRE which can potentially regulate expression transcriptionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Dehydrogenase↗
PubMed1990

A glucocorticoid-resistant rat hepatoma cell variant contains functional glucocorticoid receptor.

The mechanism of glucocorticoid resistance was studied in a rat hepatoma cell variant (6.10.2) which contains low levels of glucocorticoid receptor. These cells seem to have lost glucocorticoid-induced transcriptional responses as measured by the induction of expression of stably integrated mouse mammary tumor virus gene and the endogenous tyrosine aminotransferase gene, as well as the transcriptional suppression of glucocorticoid receptor gene expression. However, characterization of the glucocorticoid resistance in 6.10.2 cells revealed that the receptor is indistinguishable from the wild-type receptor with respect to hormone binding and affinity for both nonspecific and specific DNA sequences. The levels of the receptor mRNA and the total immunoreactive protein found in 6.10.2 cells were about 20% of those found in wild-type cells. Further analysis of 6.10.2 cells demonstrated that the receptor was indeed biologically functional. First, treatment of 6.10.2 cells with 8-bromo-cAMP elevated the endogenous glucocorticoid receptor levels 2-fold and restored responsiveness to glucocorticoids. Second, pretreatment of the cells with cycloheximide also led to acquisition of cellular responsiveness to glucocorticoids. We propose that there exists a "threshold" level of glucocorticoid receptor which is required for responsiveness and that under normal culture conditions, the level of glucocorticoid receptor in 6.10.2 cells is below this threshold. However, glucocorticoid responsiveness can be restored by raising the glucocorticoid receptor level above the threshold with 8-bromo-cAMP or, alternatively, by removing the threshold barrier with cycloheximide.

Animals↗
PubMed1990

A technique for temporal bone sections using non-decalcified frozen guinea pig cochleas: a study of succinic dehydrogenases.

We have developed a technique for sectioning temporal bones and have studied non-decalcified frozen guinea pig cochleas to localize succinic dehydrogenases. The technique is simple and practicable. The 6-microns sections used preserve both fine cochlear structure and satisfactory histochemical localization for identifying the succinic dehydrogenases. The technique can also be extended to immunological test, detecting transmitters and investigating enzymes in the cochlea.

Animals↗
PubMed1990

Preliminary study on the microbiology of Campylobacter pyloridis and gastric histopathology.

Biopsy samples were taken endoscopically from the antral-mucosa of 693 patients with peptic ulcer and chronic gastritis presenting dyspepsia symptoms. Campylobacter pyloridis cultures were positive in 59 of 98 (60.2%) cases and histopathologically the organisms were found in 411 of 693 cases (59.3%). Pathologically, Campylobacter pyloridis was positive in 273 out of 300 patients with chronic superficial gastritis (91.0%), in 102 of 249 patients with chronic atrophic gastritis (40.9%), in 36 out of 144 patients with chronic atrophic gastritis with intestinalization or dysplasia (25.0%). We found that there was a significant association between the presence of Campylobacter pyloridis and chronic superficial gastritis, also the degree of lymphocyte infiltration showed a strong inverse association with the presence of Campylobacter pyloridis, suggesting that a local immune response might exert an important action in the eradication of this organism. These findings support the view that Campylobacter pyloridis, may be etiologically related to chronic gastritis and peptic ulceration, even though its role still remains to be determined.

Campylobacter↗
PubMed1990

[Testing different diagnostic criteria of Behçet syndrome in Chinese patients].

In order to compare the sensitivity and specificity of different diagnostic criteria of Behçet Syndrome (BS), 98 patients with BS were collected from PUMC Hospital and China-Japan friendship Hospital in Beijing. 105 patients with other connective tissue diseases were taken as controls. Results of the study showed that the sensitivity of the diagnostic criteria of the Zhangs was 100%, O'Duffy's 78.1%, M + B's 71.9%, Japan committees (1987)72.9%, Dilsen's 87.5%, International study group A 81.3% and B 79.2%. The specificity of each of the above-mentioned criteria was 85.9%, 94.3%, 96.2%, 96.2%, 93.3%, 94.3% and 98.1% respectively. The specificity of oral ulceration could be increased to 97% only if it was found together with two other major criteria during the disease course. Ocular symptoms may be 100% specificity if found together with another major criterion. Pathergy test was found positive in 62.2% of the BS patients but rarely seen in control patients and normal subjects. Therefore, it may be considered as a specific test for BS and may well be used as one of the major diagnostic criteria. The authors are of the opinion that BS could be diagnosed only when 3 of the 5 major criteria, i.e. oral ulcer, genital ulcer, erythema nodosum, uveitis/retinitis and positive pathergy test are present, or if two each of the major and minor criteria are found.

Behcet Syndrome↗
PubMed1990

Relation between plasma atrial natriuretic peptide (ANP) and glomerular ANP receptors in 5/6 nephrectomized rats.

Chronic renal failure (CRF) was induced in male wistar rats (Group I) by 5/6 nephrectomy and the sham-operated ones served as control (Group II). The results showed that in Group I, plasma atrial natriuretic peptide (ANP) levels increased progressively as the Scr was elevated. Plasma R-A rose simultaneously compared to the normal (P less than 0.001). At the 20th week after operation, urine volume and Na decreased significantly (P less than 0.05). The number of glomerular receptors decreased markedly at the 12th week (P less than 0.05) and 20th week (P less than 0.01). Our data suggest that in 5/6 nephrectomized rats, the elevation of plasma ANP level might be partly caused by the damage of glomerular ANP receptors, and the elevated plasma ANP could not play its role in diuresis, natriuresis, blood pressure depression and R-A inhibition as a result of the damage of kidney ANP receptors.

Animals↗
PubMed1990

[Detection and clinical significance of anti-histone antibody in systemic lupus erythematosus and rheumatoid arthritis].

Determinations of anti-histone antibodies (AHA) by ELISA were carried out in 109 cases of SLE, 117 of RA, the positive rate being 50.5%, 23.1% respectively, with titres in SLE patients higher than in RA. AHA was 90.2% positive in active cases of SLE patients. SLE patients with AHA showed a higher incidence of pericarditis and arthritis, but a lower rate of malar rash than SLE patients without AHA. In RA, there is a higher incidence of extraarticular manifestations in AHA positive patients IgM-AHA was this predominant AHA in RA while in SLE patients it was the IgG-AHA. For SLE, IgG-AHA which was more closely associated with anti-ds DNA was more significant than IgM-AHA.

Arthritis, Rheumatoid↗
PubMed1989

The mechanism of cAMP-induced glucocorticoid receptor expression. Correlation to cellular glucocorticoid response.

The mechanism of regulation of glucocorticoid receptor (GR) expression by cAMP was investigated in rat hepatoma cells (HTC). Incubation of HTC cells with the cAMP-inducing agent, forskolin, caused a significant increase in the levels of both [3H]dexamethasone binding capacity and GR mRNA by about 2- to 2.4-fold within 4 h. Incubation of HTC cells with the cAMP analogue, 8-bromo-cAMP, also increased the GR mRNA level to a similar degree in a concentration-dependent manner. The increase in GR mRNA did not require ongoing translation or transcription. Determination of GR mRNA stability in 8-bromo-cAMP-induced cells showed that the message had a half-life of approximately 10 h, which is about 2.5 times longer than the GR mRNA half-life in nontreated cells (t1/2 = 4 h). These results indicate that the increased steady state level of GR mRNA induced by cAMP analogue is, at least in part, caused by increased GR mRNA stability. In both forskolin-pretreated and nontreated HTC cells, dexamethasone caused an approximately 70% down-regulation of GR protein levels. However, since forskolin induced the GR level 2- to 2.4-fold, the relative amount of GR protein remaining in cells treated with both forskolin and dexamethasone was about 2- to 2.4-fold higher compared to cells treated with dexamethasone alone. This increased GR level correlated well with the increase in inducibility of two glucocorticoid regulated genes, the endogenous tyrosine aminotransferase and the stably integrated mouse mammary tumor virus. These data suggest that relatively small changes in GR levels are reflected in parallel changes in cellular response to glucocorticoid hormones. This also implicates a limiting nature of the GR protein in determining the biological response.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1989

[Antiphospholipid antibodies: clinical significance in systemic lupus erythematosus].

A radioimmunoassay using cardiolipin as antigen and labelled SPA, anti-human IgG, anti-human IgM, anti-human IgA as second antibodies in detecting anti-cardiolipin antibody with the sera from 308 patients and 70 normal controls. Among them, 126 patients were of SLE, 27 systemic sclerosis, 40 rheumatoid arthritis, 40 Sjögren syndrome, 26 other connective tissue diseases, 7 syphilis and 32 with obstetric complications. The positive rate of anticardiolipin antibody were 42.9% (SLE), 29.7% (PSS), 20% (RA), 15% (SS), 26.9% (CTD), 85.7% (syphilis), 3.1% (obstetric complication), 0% (NC). In SLE the anticardiolipin antibody were well correlated with thrombocytopenia, cerebral lupus, thrombosis of vein and spontaneous recurrent abortion. Lupus anticoagulant (APTT) was found in 21.3% of SLE and biological false positive of VDRL test in 4.8%. Both of them correlated with the anticardiolipin antibody detected by the radioimmunoassay. The authors concluded that antiphospholipid antibodies is a group of commonly seen antibodies, which may play a rule in the pathogenesis of SLE. Further study is progressing.

Adolescent↗
PubMed1989

A prospective, controlled, double-blind, cross-over study of tripterygium wilfodii hook F in treatment of rheumatoid arthritis.

A polyglycosides of Tripterygium wilfodii hook F (TWH) preparation with a code name of T2 is used in the present double-blind, controlled, cross-over study on the treatment of 70 cases of rheumatoid arthritis (RA). An impressive curative effect of T2 is confirmed much more convincingly by the present study than that by the previously reported clinical open trials. The adverse reactions and the probable pharmacological mechanism of T2 are also discussed.

Adult↗
PubMed1989

[Preliminary report on the clinical application of anti-Jo-1 antibody].

Jo-1 antigen was purified from the rabbit thymus acetone powder. Using it as antigen, we found anti-Jo-1 antibody in 25% of polymyositis, 7.1% in dermatomyositis, none in other connective tissue diseases nor non-connective tissue diseases. Other antinuclear antibodies, eg anti-RNP, anti-SSA were also found in our polymyositis-dermatomyositis patients. Our study suggested, the positivity of anti-Jo 1 antibody not only confirmed the patient's diagnosis of polymyositis but also demonstrated the autoimmune pathogenesis of this disease.

Antibodies, Antinuclear↗
PubMed1989

[Comparative study of diagnostic criteria of rheumatoid arthritis in Chinese patients].

The ARA 1958 and 1987 revised classification criteria of RA are tested in 111 consecutive patients with RA and 54 cases of non-RA connective tissue diseases from three hospitals of tertiary level in Beijing. Comparing the two criteria, the specificity was the same as 88%, whereas the sensitivity changed from 94% of 1958 criteria to 91% of 1987 criteria. Factors affecting the sensitivity of 1987 criteria were mainly the morning stiffness which became to be more than 1 hour and increasing of number of swelling joints from one to three.

Adolescent↗