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Biomedical subjects

Y Dong

Publications and source records attributed to Y Dong.

At least 235 records · Page 13Linked to original sources
PubMed1996

[CuZn-SOD determination of sera in patients with rheumatic diseases].

Superoxide anion (O2.-) plays an important part in reactive oxygen species (ROS). In order to explore its effect on the pathogenesis of rheumatic diseases, authors had determined CuZn-SOD contents of sera in 132 subjects involving the patients of rheumatic diseases (SLE, RA, etc), non-rheumatic diseases and normal controls by using enzyme linked immunosorbent assay (ELISA). The results showed the followings: CuZn-SOD contents of 27 normal subjects: 98.80 +/- 20.74 ng/ml (x +/- s); that of 27 non-rheumatic diseases cases: 72.24 +/- 16.60 ng/ml (x +/- s); of 22 SLE cases: 56.56 +/- 19.27 ng/ml (x +/- s); of 27 RA cases: 61.56 +/- 20.53 ng/ml (x +/- s); of 29 other rheumatic diseases cases: 68.97 +/- 17.79 ng/ml (x +/- s). Statistical test was made: both CuZn-SOD contents of rheumatic disease and non-rheumatic disease were lower than that of normal subjects with more significant difference (P < 0.001); compared with that of non-rheumatic diseases patients, SLE cases had significant difference (P < 0.01); RA cases had significant difference (P < 0.05); other cases of rheumatic diseases had no statistical differrence (P > 0.05). Above results suggest that superoxide anion is a non-specific inflammatory mediator which contributes to disorders with inflammatory damages (rheumatic or non-rheumatic diseases), where CuZn-SOD content tested was obviously lower than normal subjects; among the rheumatic disease patients, CuZn-SOD contents of the sera of SLE patients were the lowest because of its more autoimmune antibody, more severe inflammatory and immunological reaction. This work laid the theoretical and experimental foundation for the clinical application of exogenous CuZn-SOD in the treatment of rheumatic diseases. Combined use of CuZn-SOD scavengers may get better result because of the complexibility of ROS inflammatory mechanism.

Adolescent↗
PubMed1996

[Expression of cytokines in labial gland of Sjögren's syndrome].

OBJECTIVE: To explore the role of cytokines in the process of inflammation and destruction of minor salivary gland in Sjögren's Syndrome. (SS) METHODS: Using in situ non-isotope double hybridization method, we detected the mRNA of the following cytokines: TNF alpha, IL-1 beta, IL-6, PDGF alpha and PDGF beta in 24 labial gland biopsied sections. RESULTS: No cytokine could be detected in the normal labial glands sections. The positivity of all cytokine expression was higher in the pSS and sSS patients than that in the control. The intensity of TNF alpha expression was 3-4 fold increase in pSS compared with sSS. The different cytokines were expressed with the different grade of lymphocytic focus. The site of different cytokines was also expressed differently. The coexpression of mRNA of TNF alpha and IL-1 beta or TNF alpha and IL-6 was only seen in the inflammatory mononuclear cells but not others. The expression of TNF alpha in aciniar cells could occur earlier than the infiltration of lymphocytes in the interstitial region. It was found that the IL-6 positive group had higher positivity of serum ANA compared with the IL-6 negative group according to Ridit statistical analysis (P < 0.05). The serum anti-SSA and anti-SSB antibody had an increase tendency in the IL-6 positive group. CONCLUSION: We hypothesize that the development of SS may be secondary to some trigger agents, which activated the aciniar cells in exocrine gland of predisposed individuals. The activated acini cells secreted TNF alpha, then TNF alpha induced other cytokine expression, followed by the lymphocytes infiltration, which led to autoimmne reaction and the destruction of the exocrine gland.

Cytokines↗
PubMed1996

[Preliminary diagnostic criteria for primary Sjogren's syndrome in China].

Primary Sjogren's syndrome (pSS) is a common autoimmune connective tissue disease in China yet without a universally accepted diagnostic criteria. In this study a new criteria was proposed and compared with other six sets of criteria. Fifty-five items in 112 pSS and 185 controls were evaluated. Results show the criteria we proposed contained one major and nine minor items. For the purpose of identifying patients in clinical studies, a major with at least three of the nine minor items or at least five of the minor items should be presented. The major item is anti-SSA/SSB(+) and the minors are, (1) dry eyes or dry mouth (> 3 months, persistently), (2) swollen salivary glands (recurrently or persistently), (3) rampant dental caries, (4) Schirmer test (< 5 mm in 5 min.) or corneal staining(+), (5) unstimulated salivary flow (< 0.03 ml/min) or abornal parotid sialography, (6) minor salivary gland biopsy (> or = 1 focus), (7) renal tubular acidosis, (8) hypergammaglobuminemia (gamma globulin > or = 30%) or hypergammaglobuminemic purpura, (9) RF > 1 : 20 or ANA > 1 : 20. Other connective tissure diseases, pre-existing lymphoma, AIDS, sarcoidosis, graft vs host disease must be excluded. The criteria we proposed had a high specificity of 98.2% and sensitivity of 94.1%.

Adult↗
PubMed1996

[Immunohistochemical study of lactate dehydrogenase isoenzymes in gastric cancer: light and electron microscopic observations].

In order to study the metabolic features of gastric cancer, the relationship between intestinal metaplasia or dysplasia and gastric cancer, and the relationship between LDH isoenzymes and biological behavior of gastric cancer, the content and distribution of lactate dehydrogenase (LDH) isoenzymes in 60 cases of gastric cancer were observed with immunohistochemical and immunoelectron microscopic techniques. The results showed that the content of LDH5 in gastric cancer cells was higher than that in any cells of normal gastric epithelium except parietal cells (P < 0.001). LDH-H (LDH1-LDH4) in cancer cells was lower than in parietal cells, but was not significantly different from that in chief cells and surface epithelium. Under electron microscope, LDH5 in cancer cells was mainly distributed in the matrix of cytoplasm, while LDH-H was scarce. LDH5 in the epithelium of intestinal metaplasia (IM) or dysplasia was higher than in pyloric glandular epithelium (P < 0.05), but was not significantly different from that in cancer cells (P > 0.2). LDH-H in the epithelium of IM or dysplasia was higher than that in pyloric glandular epithelium and gastric cancer cells (P < 0.05). The results suggest that increased LDH in gastric cancer cells is resulted mainly from increased LDH5, which makes the gastric cancer cells produce more lactate, with decrease in local pH. Invasion and spread of cancer cells could be indirectly promoted through an elevated activity of acid hydrolases. IM and dysplasia may be considered as borderline lesions from normal gastric mucosa to gastric cancer.

Gastric Mucosa↗
PubMed1996

HLA-DRB1 alleles genotyping in patients with rheumatoid arthritis in Chinese.

OBJECTIVE: To explore the role of HLA-DRB1 genes in the development of rheumatoid arthritis (RA) and the correlations between HLA-DR alleles and clinical manifestations of patients with RA. METHODS: 86 patients with rheumatoid arthritis and 106 race matched controls were studied in whom HLA-DR typing was performed by the method of DNA amplification with sequence-specific primers (PCR-SSP). The subtypes of HLA-DR4 were determined by the method of hybridization of PCR products with sequence-specific oligonucleotides (PCR-SSO). The absence or presence of HLA-DR4 and its subtypes was correlated with the clinical and serological characteristics of the patients. RESULTS: Compared with controls, an increased gene frequency of HLA-DR4 (48.8% vs 17.9%, P < 0.001) and a decreased frequency of HLA-DR7 (16.3% vs 27.4%, P = 0.06) were found. The DRB1* 0405 account for 61.9% of DR4+RA patients and 21.1% of DR4+ controls (P < 0.01). There was no difference between the DR4+ and DR4- patients with respect to age, sex, duration of disease, rheumatoid factor (RF), extra-articular manifestations including secondary Sjogren's syndrome. According to the wrist X-ray stage, the patients of DR4+ were more severe than that of DR4- (P < 0.05). CONCLUSION: HLA-DR4 and DR4 subtype of DRB1*0405 are related to the development of RA in Chinese. HLA-DR4 can be a useful prognostic marker in the patients with RA.

Alleles↗
PubMed1996

[Changes of chemical constituents of radix Sophorae flavescentis in complex formulas of traditional Chinese medicine].

Experiments have been made on the changes of chemical constituents in complex formulas of traditional Chinese medicine. The results show that in the complex formula containing Radix Sophorae Flavescentis, as affected by various conditions of processing such as water, temperature and coexisting reductive substances, the content of oxymatrine tends to decrease gradually to disappear while that of matrine increase gradually.

Alkaloids↗
PubMed1995

Ocular lens gap junctions: protein expression, assembly, and structure-function analysis.

Recent advances in understanding lens fiber gap junction formation are reviewed. These include studies of junctional protein expression in the embryonic lens, and of age related changes affecting gap junction structure and composition in the adult lens. An in vitro assembly system based on detergent solubilized pore complexes and endogenous lipids has been developed to provide information on the molecular interactions involved in gap junction formation and to provide material for structure analysis. Important information on the electrical properties of lens gap junction channels is obtained using electrophysiological techniques including planar lipid bilayer analysis and patch clamping.

Animals↗
PubMed1995

An upstream control region required for inducible transcription of the mouse H1(zero) histone gene during terminal differentiation.

The replacement linker histone H1 (zero) is associated with terminal differentiation in many mammalian cell types, and its accumulation in chromatin may contribute to transcriptional repression occurring during terminal differentiation. H1 (zero) also accumulates in a variety of cell culture lines undergoing terminal differentiation. During in vitro mouse erythroleukemia cell differentiation, H1 (zero) gene expression is induced very rapidly, prior to the time when the cells actually commit to terminal differentiation. We have used a combination of transfection assays and in vitro DNA-protein interaction studies to identify nuclear protein binding sites in the H1 (zero) promoter that control expression and induction of the H1(zero) gene in mouse erythroleukemia cells. The results indicate that transcription of the H1 (zero) gene is controlled by three elements present in the upstream region of the promoter between positions -305 and -470. Site-directed mutagenesis of each of these elements showed that one of them controls inducibility of the gene in differentiating cells. The other two elements in the upstream control region affect primarily the level of transcription of the gene in undifferentiated and differentiating cells. These two elements share a DNA sequence motif consisting of a (dG)6 tract contained in an eight-base consensus, (A/C)GGGGGG(A/C). Additional copies of this motif are present elsewhere in the H1 (zero) promoter.

Animals↗
PubMed1995

Changes in lens connexin expression lead to increased gap junctional voltage dependence and conductance.

The differentiation of mouse lens epithelial cells into fiber cells is a useful model for studying the changes of the electrical properties of gap junction (cell-to-cell) channels that are induced by an alteration in connexin expression patterns. In this model, cuboidal lens epithelial cells differentiate into elongated fiber cells, and the expression of connexin43 (Cx43) in the epithelial cells is replaced with the production of high levels of Cx50 and Cx46 in the fiber cells. We now report a new procedure to isolate mouse lens fiber cell pairs suitable for double whole cell patch-clamp analysis. Analysis was also performed for fiberlike cell pairs differentiated from epithelial cells in culture. Voltage dependence and unitary conductance of fiber cell gap junction channels were determined and compared with the corresponding values previously measured for the channels joining lens epithelial cells and for lens connexin channels formed in Xenopus oocyte pairs. Our results support a differentiation-induced shift toward stronger gap junctional voltage dependence and larger unitary conductances in the fiber cells. Our data further reflect a balanced functional contribution of Cx50 and Cx46 in the fiber cell-to-cell channels rather than a predominance of a single connexin.

Animals↗
PubMed1995

Ins(1,4,5)P3 activates Drosophila cation channel Trpl in recombinant baculovirus-infected Sf9 insect cells.

The trp-like (trpl) gene product (Trpl) is thought to form a nonselective cation channel important for signal transduction in Drosophila photoreceptor cells. This channel may be the insect homologue of mammalian channels involved in Ca2+ signal transduction. To determine the mechanism of receptor-mediated activation of Trpl, whole cell membrane currents were examined in Sf9 insect cells after infection with recombinant baculovirus. Stimulation by bradykinin increased whole cell Trpl currents three- to fivefold. Similar activation of Trpl was observed by inclusion of D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] in the pipette solution during whole cell recordings. These currents were 1) not seen in noninfected cells or in cells expressing only the B2 receptor, 2) mimicked by D-myo-inositol 2,4,5-trisphosphate, and 3-deoxy-3-fluoro-D-myo-inositol 1,4,5-trisphosphate, 3) not seen with D-myo-inositol 1,4-bisphosphate or D-myo-inositol 1,3,4,5-tetrakisphosphate, and 4) blocked by heparin, but not by de-N-sulfated heparin. In contrast, Trpl currents were unaffected by thapsigargin. These results demonstrate that the Trpl cation channel is activated by Ins(1,4,5)P3 in a heparin-sensitive fashion. Regulation of channel activity by Ins(1,4,5)P3 may occur by a number of mechanisms, including direct binding of Ins(1,4,5)P3 to the Trpl channel or direct physical interaction between the Ins(1,4,5)P3 receptor/Ca(2+)-release channel of the endoplasmic reticulum and the Trpl protein.

Animals↗
PubMed1995

Breast cancer selective gene expression and therapy mediated by recombinant adenoviruses containing the DF3/MUC1 promoter.

The high molecular weight mucin-like glycoprotein, DF3 (MUC1), is overexpressed in the majority of human breast cancers. Here we demonstrate that replication defective recombinant adenoviral vectors, containing the DF3 promoter (bp -725 to +31), can be used to express beta-galactosidase (Ad.DF3-betagal) and the herpes simplex virus thymidine kinase (HSV-tk) gene (Ad.Df3-tk) in DF3 positive breast carcinoma cell lines. In vivo experiments using breast tumor implants in nude mice injected with Ad.DF3-betagal demonstrated that expression of the beta-galactosidase gene is limited to DF3-positive breast cancer xenografts. Moreover, in an intraperitoneal breast cancer metastases model, we show that i.p. injection of Ad.DF3-tk followed by GCV treatment results in inhibition of tumor growth. These results demonstrate that utilization of the DF3 promoter in an adenoviral vector can confer selective expression of heterologous genes in breast cancer cells in vitro and in vivo.

Adenoviruses, Human↗
PubMed1995

Insulin-like growth factor (IGF) I and retinoic acid induce the synthesis of IGF-binding protein 5 in rat osteoblastic cells.

The insulin-like growth factor (IGF) regulatory system has a major impact on bone physiology. Among the modulators of IGFs, a family of structurally related proteins, the IGF-binding proteins (IGFBPs), have been shown to either potentiate or inhibit IGF actions on bone growth. However, the regulation of IGFBP expression in bone cells is not completely understood. In the present study, the expression of IGFBP-5 was analyzed in primary osteoblastic cells (Ob cells) isolated from 22-day-old fetal rat calvariae. Treatment of Ob cells with either IGF-I or all-trans-retinoic acid (RA) caused a time- and dose-dependent increase in IGFBP-5 messenger RNA (mRNA) levels, as determined by Northern blot analysis. Stimulation of IGFBP-5 mRNA was obtained at 100 nM IGF-I between 6 and 16 h (2- to 2.5-fold) and 100 nM RA between 16 and 24 h (3- to 4-fold). Concomitant treatment of Ob cells with IGF-I and RA revealed an additive effect and a 5- to 7-fold increase in IGFBP-5 mRNA levels after 16-24 h. The effect of IGF-I and RA and their combination on IGFBP-5 transcripts was similar in confluent and subconfluent cultures of Ob cells. IGF-I and RA did not change IGFBP-5 mRNA stability in Ob cells after transcription arrest with the RNA polymerase II inhibitor 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole. IGF-I and RA at 100 nM elevated the levels of IGFBP-5 heterogenous nuclear RNA, measured by reverse transcription-polymerase chain reaction. The effect was similar to that observed on mRNA levels. IGFBP-5 from rat Ob cells appeared as a single band of 31 kilodaltons in both the conditioned medium and the extracellular matrix as determined by Western immunoblots. IGF-I and RA, both at 100 nM, increased IGFBP-5 by 2- to 3-fold after 24 h. In conclusion, IGF-I and RA modify the synthesis and secretion of IGFBP-5 in rat Ob cells through pathways that may involve increased transcription and elongation and/or altered processing of heterogenous nuclear RNA. Our data suggest that IGFBP-5 may play a role in the osteoblastic-differentiated function regulated by IGF-I and RA.

Animals↗
PubMed1995

[Sensitivity of Plasmodium falciparum to seven antimalarials in China-Laos border].

The sensitivity of P. falciparum to chloroquine (CHL), piperaquine (PIP), artesunate (ATS), dihydroartemisinine (DAT), artemether (ATM), arteether (ATE) and pyronaridine (PRN) were assayed by in vitro microtechnique in China-Laos border in 1992. The resistance rates of isolates from the south of Yunnan of China in the border were 97.0%, 96.4%, 12.5%, 16.0%, 6.3% and 34.5%, respectively; ID50 were 119.0, 320.0, 7.2, 5.4, 295.0, 74.4 and 31.9 nmol/L, ID95 were 625.0, 2426.0, 42.2, 36.6, 767.0, 371.1 and 325.2 nmol/L. The resistance rates of isolates from the north border of Laos were in order 9/10, 8/10, 1/5 to CHL, PIP, PRN, ID50 were 114.0, 166.9, 16.4 nmol/L, ID95 were 570.0, 631.1 and 107.7 nmol/L. All the isolates from Laos were sensitive to ATS, DAT, ATM and ATE. ID50 were 5.0, 4.4, 91.6 and 56.7 nmol/L, ID95 were 23.4, 11.1, 3276.1 and 223.9 nmol/L, respectively. The results indicate that P. falciparum in the border was highly resistant to CHL and PIP, while most of the isolates were susceptible to the other 5 of the above-mentioned drugs. A comparison between the isolates from China and Laos showed that there was no significant difference in resistance degree to CHL but the sensitivity of isolates from China to other 6 drugs was lower than those from Laos.

Animals↗
PubMed1995

An association study between essential hypertension and HLA-DRB1 alleles.

It is well established that genetic and environmental factors are involved in the etiology of essential hypertension (EH). Previous studies have suggested that at least one of the HLA genes is responsible for the genetic susceptibility to EH. Our aim in the present study was to investigate this issue in China by the PCR-SSP HLA-DRB1 typing method. The results showed an increased frequency of HLA-DR2 and a decreased frequency of HLA-DR7 with EH patients compared with controls. We consider that HLA-DR2 may represent a marker for susceptibility to EH in the North Chinese population.

Alleles↗
PubMed1995

[Investigation of blood supply of bronchogenic carcinoma deriving from pulmonary artery].

Microfil perfusion technique was used to investigate the blood supply of bronchogenic carcinoma deriving from pulmonary artery on 20 fresh specimens of lung cancer, including 11 squamous carcinoma, 6 adenocarcinoma, 1 alveolar cell carcinoma and 2 undifferentiated carcinoma cases. The results showed that the appearance and quantity of pulmonary blood supply of bronchogenic carcinoma depended on and changed with the site, activity, growth mode as well as the local condition of tumor nodules; pulmonary artery supplied blood to the periphery of the tumor and its innermost part as well; vessels from pulmonary artery in tumor nodules were generally less in number than those in the surrouding normal lung tissues around. The results suggested that the tumor blood supply from pulmonary artery should be evaluated comprehensively and dynamically; during interventional chemotherapy via pulmonary artery, patients should be selected carefully and the catheter for infusion placed in suitable position so as to gain the best therapeutic effect.

Adenocarcinoma↗
PubMed1995

Rapid HLA-DRB1 generic typing by PCR-SSP method.

We report a simple and rapid HLA-DRB1 generic typing method, PCR-SSP, which is practical and inexpensive. We use 9 sequence-specific primers and 2 group specific primers to define the HLA-DRB1 specificities DR1, DR2, DR3, DR4, DR5, DR6, DR7, DR8, DR9 and DR10. The HLA DR3, DR5, DR6 and DR8 can be amplified by the two primers of DR3568 and DRB1. The DR6 specificity can be identified by excluding the DR3, DR5 and DR8 when the DR3568 are positive. Any individuals can be typed with some exception: the three pairs of phenotype DR3/DR3 and DR3/DR6, DR5/DR5 and DR5/DR6, DR8/DR8 and DR8/DR6 cannot be discriminated from each other. We typed 106 unrelated healthy people from Beijing locations in two weeks. We think this typing method is suitable to replace the error-prone serologic HLA-DR tests in routine clinical practice, including the prospective typing of cadaveric organ donors.

Base Sequence↗