The glucocorticoid receptor and a putative repressor protein coordinately modulate glucocorticoid responsiveness of the mouse mammary tumor virus promoter in the rat hepatoma cell line M1.19

Signal transduction by glucocorticoid hormones is mediated by the intracellular glucocorticoid receptor protein. The mechanisms determining cell type- or tissue-specific differences in hormone responsiveness remain, however, unclear. To address this issue we have used two different rat hepatoma cell lines, 762 and 6.10.2, respectively, in which mouse mammary tumor virus has been stably integrated. Nuclear extracts from both of these cell lines contained a factor that bound to a sequence motif extending from -163 to -147 in the mouse mammary tumor virus promoter and that appeared to repress hormonal induction of viral mRNA expression. Transient transfection experiments indicated that the cellular levels of this putative repressor did not affect basal promoter activity; this factor appeared rather to determine cellular sensitivity to glucocorticoids. Moreover, in these experiments the relative levels of the glucocorticoid receptor appeared to be the main determinant of maximum inducibility of virus expression by hormone. Taken together, these data indicate that the differential expression patterns of receptor versus the putative repressor protein may determine the level of hormonal responsiveness of target genes in glucocorticoid-sensitive tissues.

[The manifestations of the nervous system in primary Sjogren syndrome]

We reported 9 cases of primary Sjogren syndrome (SS) who were complicated with nervous system involvement. All were women. Age between 24 to 58 years old. Their clinical symptoms of the nervous system varied widely, 7 of them manifested with the involvement of central nervous system, the main features were in case 1 bouts of seizures, case 2 multi-level damage of the brain and spinal cord which was similar to multiple sclerosis, case 3 recurrent hemiplegia caused by cerebral thrombosis then fatal vascular hemorrhage, case 4 sudden hemiplegia, case 5 persistent psychological disturbance, case 6 cranial neuropathy of V and VII, case 9 multi-focal symptoms of ataxia, myelopathy and transient blindness. 5 of the 9, case 3, 6-9 all appeared with the symptoms of peripheral neuropathy, case 7 also complicated with carpal tunnel syndrome. 4 of the 9 cases also complicated with renal tubular acidosis and/or chronic active hepatitis and/or fibrosing alveolitis and/or thrombocytopenic purpura and/or myositis. No differences of the positivity of autoantibodies was observed between those with or without nervous system involvement.

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.

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.

Prostaglandin E1 activates a chloride current in Jurkat T lymphocytes via cAMP-dependent protein kinase

Patch-clamp studies have identified a cAMP-dependent Cl- conductance in lymphocytes that is defectively regulated in cystic fibrosis. In this study we used 125I efflux and whole-cell patch-clamp studies to investigate whether prostaglandin E1 (PGE1), an agonist that generates intracellular cAMP in Jurkat T lymphocytes, activates a Cl- conductance. Stimulation of T cells by externally applied PGE1 stimulated 125I efflux and activated a slowly developing membrane current. When external and internal Cl- were about equal, the current reversed at about zero mV, but when external Cl- was lowered from 157 to 7 mM the reversal potential shifted 75 mV in the positive direction, demonstrating that the current carrier was Cl-. In addition, the current was blocked by 10 microM 5-nitro-2(3-phenylpropylamino) benzoic acid (NPPB), a potent Cl- channel blocker. A membrane-permeable cAMP analog mimicked the effect of PGE1, whereas intracellular application of a cAMP antagonist Rp-cAMP blocked the effect of PGE1. Addition of purified catalytic subunit of cAMP-dependent protein kinase (PKA) plus ATP to the recording pipette also activated a similar current, whereas internally applied Walsh inhibitor, the synthetic peptide inhibitor of PKA, blocked the PGE1 effect. These results suggest that PGE1, acting through PKA, activates a Cl- current in Jurkat T cells.

Inhibition of mitochondrial respiratory function by an organic solvent extractable component from an extract of burn eschar

Saline extracts of burn eschar (CEBE) and normal skin (CENS) caused inhibition to mitochondrial respiration and inner membrane function. Ethyl acetate extracts from CEBE (D1) and CENS (D'1) caused depression of the Respiratory Control Ratio, (RCR), an inhibition of respiration rate in state 3 and stimulation to state 4 respiration. Excellent linear correlations exist between the degree of inhibition to state 3, rate of stimulation to state 4 respiration and the logarithm of doses of D1 and D'1. The effective dose ranges (0.75-0.25 mg/ml for D1 and 4-1 mg/ml for D'1) differ by one order of magnitude. The activity of NADH dehydrogenase and succinate dehydrogenase of mitochondria after incubation with the highest toxic dose of D1 or D'1 remained normal. Dinitrophenol (DNP)-stimulated respiration was moderately inhibited by D1 and D'1. No change of oligomycin-sensitive ATPase activity was demonstrated. Exogenous malondialdehyde (MDA) did not show any inhibitory effect. Preliminary studies show that D1 contains a family of free fatty acids (FFA). Incubation of normal mitochondria with D1 increased the content of saturated FFA and a decrease of unsaturated FFA. The role of other peroxidative products is under investigation.

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.

Identification and characterization of a cis-acting element that interferes with glucocorticoid-inducible activation of the mouse mammary tumor virus promoter

The rat hepatoma cell line M1.19 is stably infected by the mouse mammary tumor virus (MMTV), and the expression of the virus is induced by glucocorticoid treatment. However, in the 6.10.2 variant of M1.19, an increase in MMTV transcription is hardly detectable upon exposure to hormone. The mechanism of hormone-unresponsiveness in these cells has been unclear. In this study, we show that nuclear extract from 6.10.2 cells contains a specific DNA-binding activity that recognizes a sequence motif extending from positions -163 to -147 on the MMTV promoter. An oligonucleotide probe spanning this region binds a nuclear factor distinct from the glucocorticoid receptor. In vivo competition experiments, where increased amounts of a plasmid containing this element were transfected into 6.10.2 cells, showed a dose-dependent increase in hormonal inducibility of MMTV expression. Together, these results indicate that this sequence motif negatively modulates glucocorticoid-inducible activation of the MMTV promoter. Moreover, we have characterized a nuclear factor that preferentially binds to the coding strand of this element.

[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.

The mechanism for glucocorticoid-resistance in a rat hepatoma cell variant that contains functional glucocorticoid receptor

The mechanism of glucocorticoid resistance has been studied in a rat hepatoma cell variant (6.10.2), which contains low levels of glucocorticoid receptor (GR). These cells seem to have lost all the glucocorticoid-induced transcriptional responses as measured by the lack of induction of expression of stably integrated mouse mammary tumor virus (MMTV) and the endogenous gene tyrosine aminotransferase (TAT), as well as the transcriptional suppression of GR gene expression. Physico-chemical characterization of the GR in the glucocorticoid resistant 6.10.2 cells revealed that the receptor is indistinguishable from the wild-type receptor with regard to size, hormone- and DNA-binding. 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. Treatment of 6.10.2 cells with 8-bromo-cAMP, which induced the endogenous GR level two-fold, restored responsiveness to glucocorticoids. Secondly, pretreatment of the cells with cycloheximide also led to reacquisition of cellular responsiveness to glucocorticoids. We propose that there exists a "threshold" level of GR, which is required for responsiveness and that under normal culture conditions, the level of GR in 6.10.2 cells is below this threshold. Glucocorticoid responsiveness can be restored by raising the GR level above the threshold with 8-bromo-cAMP or, alternatively, by removing the threshold barrier (repressor protein) with cycloheximide. Finally, the existence of such a repressor protein for MMTV induction was shown by in vivo titration with an isolated negative cis-element from the MMTV promoter.

Regulation of glucocorticoid receptor expression

A limiting factor determining the sensitivity of a cell to glucocorticoid hormones is the intracellular concentration of the glucocorticoid receptor (GR) protein. By regulating the expression of GR the cell is able to adapt to both changes in its hormone environment and to the varying requirements for biological response. Studies on the regulation of GR expression have shown this to be a complex process which involves both transcriptional and posttranscriptional mechanisms. Although GR is more or less constitutively expressed in most tissues its concentration varies under different physiological conditions. GR expression is regulated by a number of different agents including factors which act through a second messenger pathway. This allows the cell to control glucocorticoid regulated gene expression through a complex but integrated hormonal network. Here we summarize our studies on GR regulation with emphasis on: i), GR autoregulation; ii), the effect of cAMP on GR expression, and iii), GR expression during fetal rat lung development.

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.

[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.

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)

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.

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.

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.

[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.

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.

[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.

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.

[The clinical significance of anti-RNP antibody]

67 cases of anti-RNP antibody were reported in different patients with connective tissue disease. The high titre of anti-RNP antibody not only presents in patients with mixed connective tissue disease (MCTD), but also in individual patient with systemic lupus erythematosus (SLE). Anti-RNP antibody is usually associated with clinical manifestation of raynauds phenomena, myositis, and sclerodactyly. The clinical significance of anti-RNP antibody and the diagnosis about MCTD were discussed in this article.