151
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Leung KP, Yan T, Li LS. Intracerebral haemorrhage and Qigong. Hong Kong Med J 2001; 7:315-8. [PMID: 11590277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
We report on a 65-year-old woman who presented with acute right-sided weakness because of an intracerebral (thalamic) haemorrhage. As a Qigong enthusiast with a long-standing history of hypertension, she developed a stroke syndrome soon after practising Qigong one morning. Following neurological recovery, the patient exhibited erratic blood pressure responses while practising Qigong, despite the fact that resting blood pressure was normal. The haemodynamic responses to exercise are discussed and a review of the therapeutic implications of practising Qigong is presented.
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Affiliation(s)
- K P Leung
- Rehabilitation Unit, University Department of Medicine, Tung Wah Hospital, Sheung Wan, Hong Kong
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152
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Abstract
Transforming growth factor-beta (TGF-beta) has been shown to both inhibit and to stimulate bone resorption and osteoclastogenesis. This may be due, in part, to differential effects on bone marrow stromal cells that support osteoclastogenesis vs. direct effects on osteoclastic precursor cells. In the present study, we used the murine monocytic cell line, RAW 264.7, to define direct effects of TGF-beta on pre-osteoclastic cells. In the presence of macrophage-colony stimulating factor (M-CSF) (20 ng/ml) and receptor activator of NF-kappaB ligand (RANK-L) (50 ng/ml), TGF-beta1 (0.01-5 ng/ml) dose-dependently stimulated (by up to 120-fold) osteoclast formation (assessed by the presence of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells and expression of calcitonin and vitronectin receptors). In addition, TGF-beta1 also increased steady state RANK mRNA levels in a time- (by up to 3.5-fold at 48 h) and dose-dependent manner (by up to 2.2-fold at 10 ng/ml). TGF-beta1 induction of RANK mRNA levels was present both in undifferentiated RAW cells as well as in cells that had been induced to differentiate into osteoclasts by a 7-day treatment with M-CSF and RANK-L. Using a fluorescence-labeled RANK-L probe, we also demonstrated by flow cytometry that TGF-beta1 resulted in a significant increase in the percentage of RANK+ RAW cells (P < 0.05), as well as an increase in the fluorescence intensity per cell (P < 0.05), the latter consistent with an increase in RANK protein expression per cell. These data thus indicate that TGF-beta directly stimulates osteoclastic differentiation, and this is accompanied by increased RANK mRNA and protein expression.
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Affiliation(s)
- T Yan
- Endocrine Research Unit, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA
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153
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Yan T, Zhou M, Fu M, Wang Y, Yu R, Li J. Inhibition of egg hatching success and larvae survival of the scallop, Chlamys farreri, associated with exposure to cells and cell fragments of the dinoflagellate Alexandrium tamarense. Toxicon 2001; 39:1239-44. [PMID: 11306136 DOI: 10.1016/s0041-0101(01)00080-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report an apparently novel toxic effect of the dinoflagellate Alexandrium tamarense, manifested by inhibition of the egg hatching success of the scallop, Chlamys farreri. The hatching rate of C. farreri approached only 30% of controls when its fertilised eggs were exposed for 36h to A. tamarense cells or cellular fragments at a concentration of 100 cells/ml, and the hatching rate was just 5% after exposure to A. tamarense of 500 cells/ml. Similar exposures of the fertilised scallop eggs to two other algal species, the diatom Phaeodactylum tricornutum and the raphidophyte Heterosigma carterae, resulted in no such toxicity or inhibitory effects. Likewise, exposure of eggs to standard STX toxin, as well as to A. tamarense cell contents (supernant of re-suspended algal cells following ultrasonication and centrifugation), did not elicit this inhibitory response. However, exposure of the scallop eggs to cell cultures, intact algal cells, or cell fragments of A. tamarense produced marked toxicity. The alga also influenced larvae at early D-shape stage of scallop. The survival rates began to decrease significantly after exposed for 6 days at concentration of 3000 cells/ml and above; no larvae could survive after 14-day exposure to A. tamarense at 10,000 cells/ml or 20-day at 5000 cells/ml. The results indicated the production of novel substances from A. tamarense which can cause adverse effects on egg hatching and survival of the scallop larvae. The experiment also found that the developmental stages before blastula was the developmental period most sensitive to the A. tamarense toxin(s) and the alga at early exponential stage had the strongest effect on egg hatching comparing with other growth phases. The adverse effect of A. tamarense on early development of scallops may cause decline of shellfish population and may have further impact on marine ecosystem.
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Affiliation(s)
- T Yan
- Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China.
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154
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155
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Wang H, Yan T, Tan JT, Gong Z. A zebrafish vitellogenin gene (vg3) encodes a novel vitellogenin without a phosvitin domain and may represent a primitive vertebrate vitellogenin gene. Gene 2000; 256:303-10. [PMID: 11054560 DOI: 10.1016/s0378-1119(00)00376-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
By analysis of zebrafish EST (expressed sequence tag) clones from an adult cDNA library, we have identified 44 clones, about 11% of the adult EST clones, encoding vitellogenins. These vitellogenin EST clones have been derived from at least seven distinct vitellogenin genes. One of the largest vitellogenin cDNA clones, vg3, and its 5' extended clone isolated by 5' RACE (rapid amplification of cDNA ends)-PCR, have been sequenced completely. The deduced complete sequence includes a predicted mature vitellogenin of 1233 amino acids and a truncated signal peptide of 18 amino acids. Interestingly, the predicted vitellogenin has no polyserine phosvitin domain. The lack of the phosvitin domain was confirmed by isolation and sequencing of the vg3 genomic region. Phylogenetic analysis indicates that the phosvitinless vitellogenin is an intermediate between invertebrate vitellogenins and all known vertebrate vitellogenins, and thus may represent a primitive vertebrate vitellogenin. Like other vitellogenins in vertebrates, the phosvitinless vitellogenin is also synthesized mainly in the liver and weakly in the intestine.
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Affiliation(s)
- H Wang
- Department of Biological Sciences, National University of Singapore, 119260, Singapore, Singapore
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156
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Li S, Yan T, Yang JQ, Oberley TD, Oberley LW. The role of cellular glutathione peroxidase redox regulation in the suppression of tumor cell growth by manganese superoxide dismutase. Cancer Res 2000; 60:3927-39. [PMID: 10919671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Manganese-containing superoxide dismutase (MnSOD) is an essential primary antioxidant enzyme that converts superoxide radical to hydrogen peroxide and molecular oxygen within the mitochondrial matrix. Cytosolic glutathione peroxidase (GPX) converts hydrogen peroxide into water. MnSOD is reduced in a variety of tumor types and has been proposed to be a new kind of tumor suppressor gene, but the mechanism(s) by which MnSOD suppresses malignancy is unclear. According to the enzymatic reactions catalyzed by MnSOD and cytosolic GPX, change in the cellular redox status, especially change attributable to accumulation of hydrogen peroxide or other hydroperoxides, is a possible reason to explain the suppression of tumor growth observed in MnSOD-overexpressing cells. To test this possible mechanism, we transfected human cytosolic GPX cDNA into human glioma cells overexpressing MnSOD. The results showed that GPX overexpression not only reversed the tumor cell growth inhibition caused by MnSOD overexpression but also altered the cellular contents of total glutathione, reduced glutathione, oxidized glutathione, and intracellular reactive oxygen species. Overexpression of GPX also inhibited degradation of the inhibitory subunit alpha of nuclear factor-KB. These results suggest that hydrogen peroxide or other hydroperoxides appear to be key reactants in the tumor suppression by MnSOD overexpression, and growth inhibition correlates with the intracellular redox status. This work suggests that manipulations that inhibit peroxide removal should enhance the tumor suppressive effect of MnSOD overexpression.
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Affiliation(s)
- S Li
- Radiation Research Laboratory, College of Medicine, The University of Iowa, Iowa City 52242, USA
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157
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Bostwick DG, Alexander EE, Singh R, Shan A, Qian J, Santella RM, Oberley LW, Yan T, Zhong W, Jiang X, Oberley TD. Antioxidant enzyme expression and reactive oxygen species damage in prostatic intraepithelial neoplasia and cancer. Cancer 2000; 89:123-34. [PMID: 10897009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Oxidative stress results in damage to cellular structures and has been linked to many diseases, including cancer. The authors sought to determine whether the expression of three major antioxidant enzymes, copper-zinc superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), and catalase, was altered in human prostate carcinoma and its likely precursor, high grade prostatic intraepithelial neoplasia (PIN). The level of reactive oxygen species damage was evaluated by measuring the expression of the DNA adduct 8-hydroxydeoxyguanosine. METHODS The authors evaluated the tissue expression of the antioxidant enzymes in prostate carcinoma by immunohistochemistry, immunogold electron microscopy, and enzymatic assay. The polymerase chain reaction was used to amplify and screen tissue specimens for the genes of SOD1, SOD2, and extracellular SOD (SOD3). Matched paraffin embedded tissue sections were evaluated by RNA in situ hybridization for expression of SOD1 and immunohistochemically for the DNA adduct 8-hydroxydeoxyguanosine. RESULTS All prostatic tissues, including cancer, displayed immunoreactivity for the three antioxidant enzymes in epithelial cells, with no staining of the stroma, inflammatory cells, or endothelial cells. The number of immunoreactive cells was greater in benign epithelium than in PIN and cancer for each enzyme. The mean percentage and intensity of immunoreactive cells was greatest for SOD2, intermediate for SOD1, and lower for catalase. Staining in cancer was heterogeneous. Immunogold ultrasound studies revealed strong mitochondrial labeling for SOD2, which was greater in benign epithelium than in cancer; SOD1 labeling was invariably weaker, with nuclear labeling in benign epithelium and cytoplasmic labeling in cancer cells. There was no difference in enzyme activity for the three antioxidant enzymes between benign epithelium and cancer. No mutations were found in the 5 exons of SOD1, 5 exons of SOD2, and 3 exons of SOD3, except for 3 of 20 cases with polymorphisms for exon 3 of SOD1. Intense nuclear immunoreactivity for 8-hydroxydeoxyguanosine was present in fewer than 3% of epithelial cells, with no apparent differences among benign epithelium, PIN, and cancer. CONCLUSIONS SOD1, SOD2, and catalase had lower expression in PIN and prostate carcinoma than in benign epithelium. The number of immunoreactive cells in PIN was similar to cancer, indicating that these are closely related. Enzyme activities were variable, with no difference between benign epithelial cells and cancer, although this lack of change in enzyme activity could have been due to the presence of contaminating benign cells within the cancer specimens. The results of reactive oxygen species damage were found only in the epithelium and not in the stroma. Expression of the DNA adduct 8-hydroxydeoxyguanosine was present in fewer than 3% of cells, with no apparent differences among benign epithelium, PIN, and cancer. These findings suggest that oxidative stress is an early event in carcinogenesis.
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Affiliation(s)
- D G Bostwick
- Bostwick Laboratories, Richmond, Virginia 23294, USA
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158
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Yan T, Agnew R, Gordon F, Porter M. Prediction of methane energy output in dairy and beef cattle offered grass silage-based diets. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0301-6226(99)00145-1] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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159
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Kou B, Lü H, Yuan Y, Yan T, Zhou D. [Clinical analysis of 13 infected total knee replacements]. Zhonghua Wai Ke Za Zhi 2000; 38:253-5. [PMID: 11832039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the cause, treatment and its result of infected total knee replacements (TKRs). METHODS Between 1987 and 1999, 13 infected TKRs in 13 patients were treated with surgical debridement and one-stage or two-stage reimplantation. The preoperative average ROM of knees was 55 degrees and the average Hospital for Special Surgery (HSS) knee score was 36.5 points. Clinical results were evaluated after average follow-up for 3 years and 5 months. We analyzed the factors for TKR infection. RESULTS No recurrent infection was noted, and pain was significantly alleviated in all patients. The average ROM of knees was 85 degrees and the average HSS knee score was 73.5 points. CONCLUSIONS The high risk factors for TKR infection are rheumatoid arthritis, steroid administration, associated diabetes mellitus, hinged prosthesis and previous knee surgery. Early surgical debridement with intravenous antibiotics is necessary as soon as deep infection is detected. Two-stage reimplantation is more effective in eradicating deep infection than single debridement or one-stage reimplantation.
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Affiliation(s)
- B Kou
- Arthritis and Clinic Research Center, People's Hospital, Beijing Medical University, Beijing 100044, China
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160
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Zhang HJ, Yan T, Oberley TD, Oberley LW. Comparison of effects of two polymorphic variants of manganese superoxide dismutase on human breast MCF-7 cancer cell phenotype. Cancer Res 1999; 59:6276-83. [PMID: 10626823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Two polymorphic variants of manganese superoxide dismutase (MnSOD), with either Ile or Thr at amino acid 58, (Ile58MnSOD or Thr58MnSOD), have been found in the human population. The MnSOD activity of these two variants and their effects on the malignant phenotype of human breast cancer MCF-7 cells were compared. It was demonstrated that MnSOD-overexpressing clones obtained from transfection of the two MnSOD cDNAs into MCF-7 cells had increased MnSOD immunoreactive protein and increased MnSOD activity. Cells overexpressing Ile58MnSOD had 3-fold higher MnSOD activity than cells overexpressing Thr58MnSOD in vivo at an equal MnSOD protein level. Tumor-suppressive effects of MnSOD-overexpressing cells were indicated by: (a) decreased plating efficiency; (b) elongated cell population doubling time; (c) lower clonogenic fraction in soft agar; and (d) complete inhibition or delayed onset of tumor formation in nude mice. When compared on the same activity basis, the suppressive effects of Ile58MnSOD were similar to those of Thr58MnSOD. However, far more Thrs58MnSOD protein was required to obtain the same amount of MnSOD activity, making the Thr58MnSOD far less effective. A dose-response suppressive effect was observed when the increase of MnSOD activity was moderate. We conclude that MnSOD is a tumor suppressor in human breast cancer, but the Thr58 form of the protein is a much less effective tumor suppressor than the Ile58 form of the protein.
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Affiliation(s)
- H J Zhang
- Radiation Research Laboratory, B180 Medical Laboratories, The University of Iowa, Iowa City 52242, USA
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161
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Abstract
Four primary antioxidant enzymes were measured in both human and rat glioma cells. Both manganese-containing superoxide dismutase (MnSOD) and copper-zinc-containing superoxide dismutase (CuZnSOD) activities varied greatly among the different glioma cell lines. MnSOD was generally higher in human glioma cells than in rat glioma cells and relatively higher than in other tumor types. High levels of MnSOD in human glioma cells were due to the high levels of expression of MnSOD mRNA and protein. Heterogeneous expression of MnSOD was present in individual glioma cell lines and may be due to subpopulations or cells at different differentiation stages. Less difference in CuZnSOD, catalase, or glutathione peroxide was found between human and rat glioma cells. The human glioma cell lines showed large differences in sensitivity to the glutathione modulating drugs 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) and buthionine sulfoximine (BSO). A good correlation was found between sensitivity to BCNU and the activities of catalase in these cell lines. Only one cell line was sensitive to BSO and this line had low CuZnSOD activity.
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Affiliation(s)
- W Zhong
- Radiation Research Laboratory, Department of Radiology, The University of Iowa, Iowa City 52242, USA
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162
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Abstract
A complete zebrafish mitochondrial 16S ribosomal RNA gene was assembled from our existing zebrafish EST clones by aligning them with the carp mitochondria 16S rRNA sequence. The overall homology between our assembled zebrafish mt 16S rRNA and the carp mt 16S rRNA is 83.5%. As the number of zebrafish ESTs grows, the assembly of more full-length cDNA sequences from overlapping EST data could be expected.
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Affiliation(s)
- T Yan
- School of Biological Sciences, National University of Singapore, Singapore
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163
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Ju B, Xu Y, He J, Liao J, Yan T, Hew CL, Lam TJ, Gong Z. Faithful expression of green fluorescent protein (GFP) in transgenic zebrafish embryos under control of zebrafish gene promoters. Dev Genet 1999; 25:158-67. [PMID: 10440850 DOI: 10.1002/(sici)1520-6408(1999)25:2<158::aid-dvg10>3.0.co;2-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although the zebrafish has become a popular model organism for vertebrate developmental and genetic analyses, its use in transgenic studies still suffers from the scarcity of homologous gene promoters. In the present study, three different zebrafish cDNA clones were isolated and sequenced completely, and their expression patterns were characterized by whole-mount in situ hybridization as well as by Northern blot hybridization. The first clone encodes a type II cytokeratin (CK), which is specifically expressed in skin epithelia in early embryos and prominently expressed in the adult skin tissue. The second clone is muscle specific and encodes a muscle creatine kinase (MCK). The third clone, expressed ubiquitously in all tissues, is derived from an acidic ribosomal phosphoprotein P0 (arp) gene. In order to test the fidelity of zebrafish embryos in transgenic expression, the promoters of the three genes were isolated using a rapid linker-mediated PCR approach and subsequently ligated to a modified green fluorescent protein (gfp) reporter gene. When the three hybrid GFP constructs were introduced into zebrafish embryos by microinjection, the three promoters were activated faithfully in developing zebrafish embryos. The 2.2-kb ck promoter was sufficient to direct GFP expression in skin epithelia, although a weak expression in muscle was also observed in a few embryos. This pattern of transgenic expression is consistent with the expression pattern of the endogenous cytokeratin gene. The 1.5-kb mck promoter/gfp was expressed exclusively in skeletal muscles and not elsewhere. By contrast, the 0.8-kb ubiquitous promoter plus the first intron of the arp gene were capable of expressing GFP in a variety of tissues, including the skin, muscle, lens, neurons, notochord, and circulating blood cells. Our experiments, therefore, further demonstrated that zebrafish embryos can faithfully express exogenously introduced genes under the control of zebrafish promoters.
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Affiliation(s)
- B Ju
- Department of Biological Sciences, National University of Singapore, Singapore
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164
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Abstract
Free radicals are involved in the aging process. In this study, the profile of primary antioxidant enzymes that scavenge reactive oxygen species (ROS) was examined for the first time in human skin fibroblasts from progeria, a premature aging disease. Altered levels of antioxidant enzymes were found in progeria cells. Basal levels of MnSOD were decreased in progeria cells as well as a blunted induction in response to chronic stress. This change may contribute to the accelerated aging process in progeria cells. In contrast, the levels of CuZnSOD showed no progeria-related change. Two H2O2 removing enzymes demonstrated a significant reduction in progeria cells: only 50% of normal CAT activity and 30% of normal GPX activity can be detected in progeria cells. This diminished H2O2 removing capacity in progeria cells may lead to an imbalance of intracellular ROS and therefore may play an important role in the development of progeria.
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Affiliation(s)
- T Yan
- B180 Medical Laboratories, The University of Iowa, Iowa City, Iowa, 52242, USA
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165
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Liao J, He J, Yan T, Korzh V, Gong Z. A class of neuroD-related basic helix-loop-helix transcription factors expressed in developing central nervous system in zebrafish. DNA Cell Biol 1999; 18:333-44. [PMID: 10235116 DOI: 10.1089/104454999315394] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Neuronal basic helix-loop-helix (bHLH) transcription factors such as neuroD and neurogenin have been shown to play important roles in neuronal development. In the present study, several distinct bHLH DNA fragments were isolated from the zebrafish genomic DNA by a pair of degenerate polymerase chain reaction (PCR) primers deduced from the conserved bHLH domains of neuroD and neurogenins. Based on the bHLH fragments, three complete neuroD-related cDNA clones, including complete coding regions, ndr1a, ndr1b, and ndr2 (ndr for neuroD related), were isolated and assembled by 5' and 3' rapid amplification of cDNA ends (RACE). A phylogenetic analysis indicated the presence of four groups of neuroD-related genes in the neuroD subfamily in vertebrates: neuroD, ndr1a/ndr1b/MATH-2, ndr2/NDRF, and neuroM/MATH3. Expression of the newly isolated neuroD-related genes was examined by reverse transcriptase (RT)-PCR and whole-mount in situ hybridization. Unlike neuroD, which was expressed broadly in primary neurons during early zebrafish development starting from 10 h postfertilization (hpf), expression of ndr1a and ndr1b started relatively late (around 22 hpf) and was restricted to the olfactory system: olfactory bulbs in the telecephalon (ndr1a and ndr1b) and olfactory organs (ndr1b) starting around 22 hpf. Although a faint ndr2 mRNA signal was detected by RT-PCR in early embryos, no ndr2 mRNA was detected by whole-mount in situ hybridization in embryos up to 72 hpf, suggesting that it is expressed rather late. Our observations suggest that the two novel neuroD-related genes, ndr1a and ndr1b, are involved in the development of the olfactory system and perhaps contribute to its functional complexity.
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Affiliation(s)
- J Liao
- Department of Biological Sciences, National University of Singapore, Singapore
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166
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Xu Y, He J, Tian HL, Chan CH, Liao J, Yan T, Lam TJ, Gong Z. Fast skeletal muscle-specific expression of a zebrafish myosin light chain 2 gene and characterization of its promoter by direct injection into skeletal muscle. DNA Cell Biol 1999; 18:85-95. [PMID: 10025512 DOI: 10.1089/104454999315655] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A zebrafish myosin light chain 2 cDNA clone was isolated and characterized. Sequence analysis of the clone revealed a high homology with the mammalian and avian genes encoding the fast skeletal muscle isoform, MLC2f. In situ hybridization and Northern blot hybridization analyses indicated that the zebrafish MLC2f mRNA is expressed exclusively in the fast skeletal muscle. Ontogenetically, the MLC2f mRNA appears around 16 hours postfertilization (hpf) in the first few well-formed anterior somites. At later stages, the MLC2f mRNA can also be detected in fin buds, eye muscles, and jaw muscles. To develop a useful model system for analyzing muscle gene regulation, the promoter of the zebrafish MLC2f gene was isolated and linked to the chloramphenicol acetyltransferase (CAT) reporter gene. The MLC2f/CAT chimeric constructs were analyzed by direct injection into the zebrafish skeletal muscle, and significant CAT activity was observed; in contrast, little or no CAT activity was generated from a similarly injected prolactin gene promoter/CAT gene construct. Within the 1 kb of the MLC2f promoter region, several MEF2-binding sites and E-boxes were identified, suggesting that MLC2f can be regulated by muscle transcription factors MEF2 and myogenic bHLH proteins. A 5' deletion analysis indicated that the proximal 79 nucleotides from the transcription start site, which contains a single MEF2-binding site, is sufficient to drive a high level of CAT activity in injected muscle. Internal deletion of the MEF2 element in the -79-bp construct caused an 80% decrease in CAT activity, whereas internal deletion of the same MEF2 element in a -1044-bp construct had no effect on induced CAT activity. These observations suggest that an MEF2 element is important to activate the MLC2f gene in muscle cells, and the effect of loss of the proximal MEF2 element can be compensated for by the presence of the upstream MEF2 elements. This study also demonstrated that direct injection of DNA into skeletal muscle is a valid and valuable approach to analyze muscle gene promoters in the zebrafish.
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Affiliation(s)
- Y Xu
- Department of Biological Sciences, National University of Singapore, Singapore
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167
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Abstract
Fourteen commercial antibodies against human antioxidant enzymes were tested on whole cell lysates by Western analysis for specificity and species crossreactivity. All antibodies, except one, recognized pure protein antigen. All four catalase antibodies were of high quality, and they could also recognize the catalases from rat, mouse, dog, and hamster cells. Two CuZnSOD antibodies were very specific for CuZnSOD protein. They could also crossreact with CuZnSOD from rat, mouse, and hamster cells, but not from dog cells. All five MnSOD antibodies detected only very high levels of MnSOD. We believe that they could not properly be used in immunohistochemistry. Three GPX antibodies could not detect the specific GPX band from cell lysates. We believe that it is difficult to use these GPX antibodies in both Western blotting and immunohistochemistry.
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Affiliation(s)
- T Yan
- Radiation Research Laboratory, Medical Laboratories, The University of Iowa, Iowa City 52242, USA
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168
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Zhang S, Cheng H, Fu Z, Zhong G, Yan T. Contribution of the absence of aspartic acid at position 57 of the HLA-DQ beta chain to predisposition to insulin-dependent diabetes mellitus in a southern Chinese population. Chin Med J (Engl) 1998; 111:694-7. [PMID: 11245021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
OBJECTIVE To investigate the association of the absence or presence of aspartic acid at position 57 of the HLA-DQ beta chain (NA or A) with susceptibility or resistance to insulin-dependent diabetes mellitus (IDDM) in a Southern Chinese population. METHODS Sixty-nine IDDM patients and 47 healthy controls in a Southern Chinese population were HLA-DQB1 genotyped by one-step sequence specific polymerase chain reaction (ssPCR). RESULTS The frequencies of NA and A were 64.5% and 35.5% in the IDDM patients, and 40.4% and 59.6% in the control subjects respectively (RR for NA was 2.68, P < 0.01). The frequencies of NA/NA, NA/A and A/A phenotypes were 47.8%, 33.3% and 18.8% in the IDDM patients, and 31.9%, 17.0% and 51.1% in the controls respectively (P < 0.01). The frequency of A/A phenotype was significantly lower in the IDDM patients than in the control subjects (RR = 0.22, P < 0.01). DQB1* 0302 and DQB1* 0201 were more frequent in IDDM patients than in control subjects. The younger the age of IDDM onset, the higher the allele frequencies of DQB1* 0201 and DQB1* 0302. CONCLUSION The present study suggests that the NA confers the susceptibility to IDDM, while the A confers the protection against IDDM in patients of Southern Chinese origin. These associations are more clearcut in childhood-onset IDDM patients.
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Affiliation(s)
- S Zhang
- Department of Endocrinology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou 510120, China
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169
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Chen C, Zhou L, Yu X, Yan T. [The development of JX-300 high quality head stereotactic guided surgical system]. Zhongguo Yi Liao Qi Xie Za Zhi 1998; 22:201-214. [PMID: 12016824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Based on the technology of three dimensions image forming and the arc stereotactic guided operator, this system has the advantages of locating precisely, convenient operation, and good result of curing. It has the imitation checking system of operation to guarantee the safe of patients.
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Affiliation(s)
- C Chen
- The First Military Medical University
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170
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Fang X, Weintraub NL, Rios CD, Chappell DA, Zwacka RM, Engelhardt JF, Oberley LW, Yan T, Heistad DD, Spector AA. Overexpression of human superoxide dismutase inhibits oxidation of low-density lipoprotein by endothelial cells. Circ Res 1998; 82:1289-97. [PMID: 9648725 DOI: 10.1161/01.res.82.12.1289] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Oxidation of LDL in the subendothelial space has been proposed to play a key role in atherosclerosis. Endothelial cells produce superoxide anions (O2.-) and oxidize LDL in vitro; however, the role of O2.- in endothelial cell-induced LDL oxidation is unclear. Incubation of human LDL (200 microg/mL) with bovine aortic endothelial cells (BAECs) for 18 hours resulted in a 4-fold increase in LDL oxidation compared with cell-free incubation (22.5+/-1.1 versus 6.3+/-0.2 [mean+/-SEM] nmol malondialdehyde/mg LDL protein, respectively; P<0.05). Under similar conditions, incubation of LDL with porcine aortic endothelial cells resulted in a 5-fold increase in LDL oxidation. Inclusion of exogenous copper/zinc superoxide dismutase (Cu/ZnSOD, 100 microg/mL) in the medium reduced BAEC-induced LDL oxidation by 79%. To determine whether the intracellular SOD content can have a similar protective effect, BAECs were infected with adenoviral vectors containing cDNA for human Cu/ZnSOD (AdCu/ZnSOD) or manganese SOD (AdMnSOD). Adenoviral infection increased the content and activity of either Cu/ZnSOD or MnSOD in the cells and reduced cellular O2.- release by two thirds. When cells infected with AdCu/ZnSOD or AdMnSOD were incubated with LDL, formation of malondialdehyde was decreased by 77% and 32%, respectively. Two other indices of LDL oxidation, formation of conjugated dienes and increased LDL electrophoretic mobility, were similarly reduced by SOD transduction. These data suggest that production of O2.- contributes to endothelial cell-induced oxidation of LDL in vitro. Furthermore, adenovirus-mediated transfer of cDNA for human SOD, particularly Cu/ZnSOD, effectively reduces oxidation of LDL by endothelial cells.
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Affiliation(s)
- X Fang
- Department of Biochemistry, University of Iowa College of Medicine, Iowa City 52242, USA
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171
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Manna SK, Zhang HJ, Yan T, Oberley LW, Aggarwal BB. Overexpression of manganese superoxide dismutase suppresses tumor necrosis factor-induced apoptosis and activation of nuclear transcription factor-kappaB and activated protein-1. J Biol Chem 1998; 273:13245-54. [PMID: 9582369 DOI: 10.1074/jbc.273.21.13245] [Citation(s) in RCA: 469] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Several recently identified intracellular proteins associate with the tumor necrosis factor (TNF) receptor and activate nuclear transcription factor (NF)-kappaB, c-Jun kinase, and apoptosis. However, the mechanism is not understood. In the present report, we investigated the role of reactive oxygen intermediates in TNF-induced signaling. Overexpression of manganese superoxide dismutase (Mn-SOD) in human breast cancer MCF-7 cells completely abolished TNF-mediated NF-kappaB activation, IkappaB alpha degradation, p65 nuclear translocation, and NF-kappaB-dependent reporter gene expression. Besides TNF, phorbol ester-, okadaic acid-, ceramide-, and lipopolysaccharide-induced activation of NF-kappaB was blocked by Mn-SOD, indicating a common pathway of activation. H2O2-induced NF-kappaB activation, however, was potentiated. In addition, Mn-SOD blocked the TNF-mediated activation of activated protein-1, stress-activated c-Jun protein kinase, and mitogen-activated protein kinase kinase. TNF-induced antiproliferative effects and caspase-3 activation, indicators of apoptosis, were also completely suppressed by transfection of cells with Mn-SOD. Suppression of apoptosis induced by okadaic acid, H2O2, and taxol was also inhibited by Mn-SOD but not that induced by vincristine, vinblastine, or daunomycin. Overall, these results demonstrate that, in addition to several recently identified signaling molecules, reactive oxygen intermediates play a critical role in activation of NF-kappaB, activated protein-1, c-Jun kinase, and apoptosis induced by TNF and other agents.
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Affiliation(s)
- S K Manna
- Cytokine Research Section, Department of Molecular Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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172
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Yan L, Yang R, Cheng H, Fu Z, Zhong G, Yan T. Protective effect of the angiotensin-converting enzyme inhibitor perindopril on diabetic glomerulopathy in streptozotocin-induced diabetic rats. Chin Med J (Engl) 1998; 111:306-8. [PMID: 10374392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
OBJECTIVES To evaluate the protective effect of the angiotensin-converting enzyme inhibitor perindopril on diabetic glomerulopathy in rats with experimentally induced diabetes and explore its possible mechanisms. METHODS Ninety-two adult male Wistar rats were randomly allocated into diabetes mellitus (DM), diabetes mellitus + perindopril (DMP) and control (C) groups. According to the duration of diabetes or observation (1, 3, 6 months), each group was randomly subdivided into DM1, DM3, DM6; DMP1, DMP3, DMP6; and C1, C3, C6 groups. Diabetes was induced by intraperitoneal injection of streptozotocin. The rats in the DMP groups received perindopril 1 mg.kg-1.d-1, through gastric intubation. Urinary protein excretion rate was determined by the method of Coomassie brilliant blue. Plasma renin activity, renal tissue renin activity, and plasma and renal tissue angiotensin II concentration were assayed by radioimmunoassay (RIA). Renal tissue total RNA was extracted by the Chomezymskis AGPC method. Renal angiotensinogen mRNA expression level was assessed by slot blot hybridization using a full length rat angiotensinogen cDNA probe labelled with 32P-dCTP and a random primer. RESULTS There was increased activity of the renin angiotensin system in diabetic rats. Perindopril decreased proteinuria and delayed the progression of glomerular basement membrane thickening. However, it did not reduce the expansion of the mesangial matrix (P < 0.05). Renin activity increased and angiotensin II concentration decreased significantly in both plasma and renal tissue in diabetes + perindopril groups (P < 0.05). CONCLUSIONS Perindopril may help prevent the progression of diabetic glomerulopathy, and the inhibition of renin angiotensin system activity may be a mechanism for this action.
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Affiliation(s)
- L Yan
- Department of Endocrinology, Zhongshan Memorial Hospital, Sun Yat-sen University of Medical Sciences, Guangzhou, China
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173
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Lu H, Yan T. [Time selection for RA synovectomy]. Zhonghua Yi Xue Za Zhi 1998; 78:169-71. [PMID: 10923521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
OBJECTIVE To discuss the time selection for RA synovectomy. METHOD Eighty-six knees in 64 RA patients underwent synovectomy in 7 years. 8 of the 64 patients were in RA stage I, 26 in II, 24 in III, 8 in IV. The mean age was 43.9 years and the average follow-up period lasted 38.2 months. RESULTS Pain relief and swelling reduction were significant clinical features after synovectomy. The overall assessment of the effect of synovectomy showed satisfactory results (72.9%) including all RA-I, and RA-II (87.2%). CONCLUSION If the patients have sustained or intractable joint swollening with exuberant synovium after strict drug therapy over half a year, synovectomy is an appropriate consideration, it is very important to select the time for synovectomy.
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Affiliation(s)
- H Lu
- Arthritis Clinic & Research Center, People's Hospital, Beijing Medical University
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174
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Zhao Q, Li J, Xu J, Yan T. [Effects of simulated microgravity on the distribution of 45Ca2+ in asparagus]. Space Med Med Eng (Beijing) 1998; 11:30-4. [PMID: 11541264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
In order to find out the effects of microgravity on the distribution of Ca2+ in asparagus seedlings, tropic reaction of rhizome, the response of cells and organizations, as well as the distribution and transportation in organization under simulated microgravity condition were observed by means of 45CaCl2 labelled autoradiography. The results showed that the distribution of calcium cations highly correlated with gravity. The absorption, distribution and transportation of calcium were greatly affected by gravity.
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Affiliation(s)
- Q Zhao
- Institute of Botany Academia Sinica, Beijing, China
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175
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Liu C, Tian Y, Shen Q, Jiang H, Ju R, Yan T, Liu C, Mang K. Cloning of 1-aminocyclopropane-1-carboxylate (ACC) synthetase cDNA and the inhibition of fruit ripening by its antisense RNA in transgenic tomato plants. Chin J Biotechnol 1998; 14:75-84. [PMID: 10196631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
A 1.7 kb fragment of ACC synthetase cDNA, one member of the ACC synthetase multigene family, was amplified from total tomato cDNA through a polymerase chain reaction (PCR) and cloned in E. coli. Restriction mapping and sequencing analysis confirmed its fidelity and correctness. The cloned ACC synthetase gene was then inserted into a binary vector pBin437, in an inverted orientation between the CaMV 35S promoter with duplicated enhancers and the Nos 3' transcriptional termination sequence, to construct an expression vector pBACC. Transgenic tomato plants were obtained by A. tumefaciens-mediated transformation of cotyledons. PCR detection and Southern blot analysis confirmed the integration of the antisense ACC synthetase gene in the transformed tomato genome. The results from RT-PCR of RNAs isolated from transgenic tomato leaves confirmed that antisense ACC synthetase RNA was synthesized in these transgenic plants. The amount of ethylene released from transgenic tomato fruits was reduced significantly to about 30% of that released by non-transformed controls. The inhibition effect of antisense RNA on fruit ripening was observed in transgenic plants and their progeny (T1). The shelf life of transgenic tomato fruits was at least 60 days at room temperature without significant change in hardness and color. After 15-20 days of treatment of the transgenic fruits with ethylene, most of them reached the ripe stage. The antisense ACC synthetase gene was inherited as a single gene in the progenies of transgenic tomatoes determined by T1 progeny analysis, consistent with the results of Southern blot analysis. Transgenic homozygotes expressing antisense ACC synthetase RNA showed prolonged shelf life in the T2 progeny.
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Affiliation(s)
- C Liu
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
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176
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Lam EW, Zwacka R, Engelhardt JF, Davidson BL, Domann FE, Yan T, Oberley LW. Adenovirus-mediated manganese superoxide dismutase gene transfer to hamster cheek pouch carcinoma cells. Cancer Res 1997; 57:5550-6. [PMID: 9407966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
As a first step in evaluating the tumor suppressor activity of the manganese superoxide dismutase (MnSOD) gene on established tumors in vivo, we used adenovirus-mediated gene transfer as a means of delivering the MnSOD cDNA to hamster cheek pouch carcinoma (HCPC-1) cells in vitro. HCPC-1 cells were transduced with the adenovirus-MnSOD construct (AdMnSOD) at multiplicities of infectivity (MOI) of 0, 10, 25, 50, 100, 150, and 200 MOI or with the adenovirus-LacZ reporter gene construct (AdLacZ) at 100 MOI. Dose-dependent increases in MnSOD immunoreactivity were seen on Western blotting and indirect immunofluorescence microscopy with increasing AdMnSOD titers. Maximal immunoreactivity was observed at 100 MOI AdMnSOD with both techniques. Moreover, we observed a concomitant 6-7-fold increase in MnSOD activity compared with parental cell levels that also peaked at 100 MOI AdMnSOD. To determine the effect of transgene-expressed MnSOD on tumor cell behavior, we examined cell growth, plating efficiency, and anchorage-dependent growth in soft agar. Cell number measured on day 13 decreased approximately 50% with 100 MOI AdMnSOD (P < 0.05) compared with parental cells. Moreover, cell doubling time increased from 38 to 44 h with 100 MOI AdMnSOD. Plating efficiency and cell growth in soft agar decreased approximately two-thirds with 100 MOI AdMnSOD (P < 0.001). These assays of the transformed phenotype in vitro all appeared to show maximal effect with 100 MOI AdMnSOD. As tumor growth in vivo is most predictable by a combination of these in vitro data, our results suggest that if MnSOD can be effectively delivered to a tumor in vivo using the adenovirus paradigm, effective tumor growth suppression can be observed.
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Affiliation(s)
- E W Lam
- Radiation Research Laboratory, Department of Radiology, The University of Iowa, Iowa City 52242-1101, USA
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177
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Liang D, Yan T. [Treatment of posterior urethral break caused by pelvic fracture and inflammatory urethral stricture via laying three silicone tubers into urethra]. Zhonghua Wai Ke Za Zhi 1997; 35:730-2. [PMID: 10677993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
We investigated a new approach for the treatment of posterior urethral break caused by pelvic fracture and inflammatory urethral stricture. 7-10 days after the operation of urethral realignment on patients with urethral break caused by pelvic fracture or after forced dilatation of inflammatory urethral stricture, three silicone tubers were laid into urethra and kept there for three months. In 66 cases of urethral break, the cure rate (58/66) was 87.9%, the improving rate (2/66) 3.0% and the failure rate (6/66) 9.1%. In 15 cases of inflammatory urethral stricture, the recovery rate was 100%. In this group of 81 cases, the cure rate was 92.6% and failure rate was only 7.4%. This new therapeutic approach proved to be simple, safe and effective. It could also dramatically reduce the infection or the stricture of urethra.
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Affiliation(s)
- D Liang
- Department of Urology, Affiliated Hospital of Ningxia Medical College, Yinchuan
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178
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Yan T, Gordon F, Ferris C, Agnew R, Porter M, Patterson D. The fasting heat production and effect of lactation on energy utilisation by dairy cows offered forage-based diets. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0301-6226(97)00121-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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179
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Abstract
A fast and economical approach, referred to as cDNA clone tagging, was adapted to identify and isolate zebrafish cDNA clones. The basic approach was to partially sequence the coding region of size selected cDNA clones and the partial sequences were then used as tags for identifying the clones through homology search. To benefit maximally from the tagging approach, two cDNA libraries, derived from embryonic and adult fish poly(A)+ RNAs, respectively, were constructed by unidirectional cloning; conceptually, they have the potential to represent all expressed zebrafish genes. A total of 1084 clones were sequenced from the two libraries, and 511 clones were identified, based on sequence homology. These identified clones were derived from at least 261 genes, encoding 48 translational machinery proteins, 47 cytosolic proteins, 43 cytoskeletal proteins, 41 nuclear proteins, 32 membrane proteins, 22 secreted proteins, 20 mitochondrial proteins and 8 proteins with an unknown location. Of the 261 distinct cDNA clones identified, 254 were isolated for the first time in the zebrafish. These tagged cDNA clones, identified and unidentified, provide rich resources for developmental analysis as well as mapping of zebrafish genome. The long-term objective of this study is to establish a tagged zebrafish gene library that can be accessed both by hybridization screening against the plasmid DNAs and by electronic screening using the sequence information.
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Affiliation(s)
- Z Gong
- School of Biological Sciences, National University of Singapore.
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180
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Yan T, Gordon F, Agnew R, Porter M, Patterson D. The metabolisable energy requirement for maintenance and the efficiency of utilisation of metabolisable energy for lactation by dairy cows offered grass silage-based diets. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0301-6226(97)00065-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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181
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Yan T, Teo LH, Sin YM. Effects of mercury and lead on tissue glutathione of the green mussel, Perna viridis L. Bull Environ Contam Toxicol 1997; 58:845-850. [PMID: 9115152 DOI: 10.1007/s001289900411] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- T Yan
- School of Biological Sciences, National University of Singapore, Singapore
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182
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Zhong W, Oberley LW, Oberley TD, Yan T, Domann FE, St Clair DK. Inhibition of cell growth and sensitization to oxidative damage by overexpression of manganese superoxide dismutase in rat glioma cells. Cell Growth Differ 1996; 7:1175-86. [PMID: 8877099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of overexpression of human manganese superoxide dismutase (MnSOD) on cell proliferation and response to oxidative stress in rat glioma cells were studied. MnSOD-overexpressing cells had a 2- to 14-fold increase in MnSOD activity, but did not have consistent changes in the activities of CuZnSOD, catalase, or glutathione peroxidase. Cells with more than a 5-fold increase in MnSOD activity became more sensitive to radiation, 1,3-bis(2-chloroethyl)-1-nitrosourea, and buthionine sulfoximine and had a lower growth rate than parental and vector control cells. The sensitivity to 1,3-bis(2-chloroethyl)-1-nitrosourea was partially reduced by pyruvate, a H2O2 scavenger. Our results suggest that overexpression of MnSOD can cause an imbalance of antioxidant enzymes, which we hypothesize results in an elevation of intracellular H2O2. Overexpression of MnSOD can either inhibit cell proliferation or increase cell death by oxidative agents, depending on the levels of peroxide-removing enzymes.
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Affiliation(s)
- W Zhong
- Radiation Research Laboratory, University of Iowa, Iowa City 52242, USA
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183
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Yan T, Oberley LW, Zhong W, St Clair DK. Manganese-containing superoxide dismutase overexpression causes phenotypic reversion in SV40-transformed human lung fibroblasts. Cancer Res 1996; 56:2864-71. [PMID: 8665527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Manganese superoxide dismutase (MnSOD) has been found to be low in a wide range of tumor cells as well as in vitro-transformed cell lines and has been implicated as a new type of tumor suppressor gene. The relationship between MnSOD activity and the malignant phenotype was studied by transfection of MnSOD cDNA into the SV40-transformed human fibroblast cell line WI-38 VA13 subline 2RA. The integration and expression of the exogenous MnSOD cDNA was confirmed in three selected clones with a 2-3.5-fold increase in MnSOD activity. The effect of elevated expression of MnSOD on the cell phenotype was determined by observing growth characteristics. Compared with the parental and neo control cells, the MnSOD-overexpressing clones had a slower growth rate, lower plating efficiency, increased anchorage dependence, and morphological differences. These changes were correlated strongly with the level of MnSOD activity. The results suggest that an increase of MnSOD activity can reverse part of the malignant phenotype in SV40-transformed human fibroblast cells. A possible mechanism is that overexpression of MnSOD might alter the intracellular redox state by modulation of the balance of reactive oxygen species.
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Affiliation(s)
- T Yan
- Radiation Research Laboratory, University of Iowa, Iowa City, Iowa 52242, USA
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184
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Cheng H, Zhang Y, Fu Z, Yan T. Age-of-onset related HLA-DQA1 genetic heterogeneity of insulin-dependent diabetes mellitus. Chin Med J (Engl) 1996; 109:474-7. [PMID: 9206083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To clarify whether there is an association of insulin-dependent diabetes mellitus (IDDM) susceptibility with HLA-DQA1 locus in adult-onset IDDM. PATIENTS AND METHODS Possible heterogeneity in immunogenetic aspects was investigated by comparing the findings on relationship between HLA-DQA1 52 Arg(+) and IDDM predisposition in three groups with different ages of IDDM onset (group A 14 years, group B 15-30 years, group C > 31 years). RESULTS The frequency of HLA-DQA1 52 Arg(+) in group A (87.5%) was higher than that in control (53.9%, P < 0.05) and in group B and C (P < 0.05). The frequency of HLA-DQA1 52 Arg(+)/Arg(+) phenotype in group A (75%) was higher than that in group C (23.1%, P < 0.05). CONCLUSION The contribution of HLA-DQA1 52 arginine to IDDM susceptibility is heterogeneous. Further study is necessary to clarify the immunogenetic entity of IDDM.
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Affiliation(s)
- H Cheng
- Department of Endocrinology, Memorial Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou
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185
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Yan T, Teo LH, Sin YM. Effects of metals on alpha-amylase activity in the digestive gland of the green mussel, Perna viridis L. Bull Environ Contam Toxicol 1996; 56:677-682. [PMID: 8645929 DOI: 10.1007/s001289900099] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- T Yan
- Department of Zoology, National University of Singapore, Singapore
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186
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Cai D, Yu B, Yan T. [Changes in cytosolic free calcium and thromboxane B2 synthesis in platelets from diabetic subjects]. Zhonghua Yi Xue Za Zhi 1995; 75:476-8, 510-1. [PMID: 7584570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using fura-2, a fluorescence indicator, we evaluated the changes of platelet cytosolic free calcium concentration ([Ca2+]i) and its role in regulation of thromboxane B2 (TXB2) synthesis in patients with diabetes mellitus (DM group, n = 27) and in healthy subjects (control group, n = 15). The A23187-evoked elevation of [Ca2+]i and TXB2 production were higher in the DM group than in the control group (P < 0.01 respectively). The rise in [Ca2+]i was correlated positively with TXB2 production. In contrast, stimulation with arachidonic acid, TXB2 production was unaltered between the groups, although arachidonate-induced [Ca2+]i was higher in the DM group than in the control group (P < 0.05). The results suggested that changes in platelets [Ca2+]i in diabetic subjects may contribute to increase in TXB2 synthesis, involved libration of free arachidonate from membrance phospholipids by the action of phospholipases. Since no significant difference was found between the diabetic patients with microangiopathy (n = 13) and without microangiopathy (n = 14), the results above may be involved in the development of diabetic microangiopathy.
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Affiliation(s)
- D Cai
- Research Unit of Endocrinology, Sun Yat-Sen University of Medical Science, Guangzhou
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187
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Shime N, Yoshioka M, Fukui M, Hatanaka T, Yan T, Tanaka Y. [The usefulness of transcutaneous gas monitoring during hemorrhagic shock; discrepancy between the two transcutaneous gas tensions of anterior thorax and femur]. Masui 1994; 43:1174-8. [PMID: 7933498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We measured transcutaneous gas tensions of both anterior thorax and femur. The differences between the two transcutaneous gas tensions were compared, as well as the relationship between the two transcutaneous and mixed venous blood gas tensions, in 10 dogs during hemorrhagic shock. The changes in femoral transcutaneous gas tensions correlated better with the changes in mixed venous gas tensions. The correlation between the two transcutaneous gas tensions were fairly good (oxygen tensions; r = .827, carbon dioxide tensions; r = .867). However, the discrepancy between the two gas tensions became greater in severe shock. Hence, oxygen tensions became smaller and carbon dioxide tensions became greater on femur than on anterior thorax. This indicates the possibility of "maldistribution of blood flow", which has already been detected between vital organs and skin, also exists between peripheral and central skin. Therefore, transcutaneous gas tensions should be monitored at peripheral skin, where gas tensions show greater changes and reflect systemic perfusion precisely than at central skin, during shock.
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Affiliation(s)
- N Shime
- Department of Anesthesiology, Kyoto Prefectural University of Medicine
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188
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Abstract
Here we have investigated and compared the effects of anti-CD4 on helper function of CD4,45RA+ versus CD4,45RO+ T cells. Only CD4,45RO+ cells, but not CD4,45RA+ cells were able to promote B cell differentiation resulting in immunoglobulin production in vitro (IgM as well as IgG) which could be inhibited by anti-CD4 MoAbs (MAX.16H5 and T151). In pokeweed mitogen (PWM)-induced B cell proliferation a similar pattern of responsiveness was obtained. When we studied the anti-CD4 effects on cytokine production in T cells stimulated in mixed lymphocyte reaction (MLR) or by mitogens, we found that neither IL-2 nor IL-4 production was dramatically influenced by anti-CD4 in CD4,45RO+ cells. This led us to the conclusion that the inhibitory effect of anti-CD4 on B cell proliferation and immunoglobulin secretion was not due to inhibition of cytokine production. To clarify this point, we investigated the ability of anti-CD4 to inhibit conjugate formation between B and T cells. It was found that CD4,45RO+ T cells formed more conjugates than CD4,45RA+ cells, and that only the conjugate formation by CD4,45RO+ T cells was inhibited by anti-CD4. These results suggest that (i) anti-CD4 inhibits T helper functions primarily by affecting CD4,45RO+ cells, and (ii) this effect is probably mediated by contact inhibition in the early phase of T-B collaboration.
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Affiliation(s)
- J Wang
- Max-Planck-Gesellschaft, Klinische Arbeitsgruppe für Rheumatologie/Immunologie Universität Erlangen-Nürnberg, Germany
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189
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Abstract
Postburn metabolic and immunological alterations may in part be due to translocation of gut exotoxin and endotoxin, which can result in tumour necrosis factor (TNF) and prostaglandin E (PGE) production by macrophages. We evaluated the effect of burn injury, plus exotoxin and endotoxin on TNF-alpha and PGE production by Kupffer cells, and peritoneal macrophages. Adult Wistar rats underwent 30 per cent TBSA burn or sham burn. Kupffer cells were harvested from rat livers and peritoneal macrophages from the abdominal cavity 24 h postburn. They were cultured overnight at 1 x 10(6) cells/ml and stimulated with saline, 5 micrograms/ml of Pseud. aeruginosa Exotoxin A (Exo-A), 5 micrograms/ml of Pseud. aeruginosa Endotoxin (Endo), Exo-A + Endo, or Exo-A + Endo + the PGE derivative 16,16 dimethyl-PGE (dPGE) (10 micrograms/ml). The supernatants were harvested after 4, 24 and 48 h of culture and assayed for TNF-alpha and PGE. Results showed that burn injury induced an increase in TNF-alpha and PGE production by Kupffer cells stimulated with Exo-A, Endo, and both Exo-A + Endo (P < 0.05). The release of TNF-alpha by Kupffer cells was downregulated by exogenous PGE (P < 0.05). The increased TNF-alpha production was inversely related to PGE levels. In conclusion, both burn injury and Exo-A potentiate the responsiveness of Kupffer cells and peritoneal macrophages to endotoxin as measured by the rate of production of TNF-alpha and PGE. PGE may locally downregulate the immune response by limiting Kupffer cells' and peritoneal macrophages' TNF-alpha production.
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Affiliation(s)
- Y L Dong
- Shriners Burns Institute, Galveston Unit, Texas
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190
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Abstract
The effects of burn injury and sepsis on intracellular lymphocyte metabolism were evaluated using a rat model. Adult Lewis rats were subjected to a sham burn, a 30% full-thickness burn, or a 30% full-thickness burn which was infected with Pseudomonas aeruginosa. One week later the animals were sacrificed, and the splenic lymphocytes were harvested and cultured for 24 hr with mitogen stimulation. Lymphocytes from the burned-infected rats were found to utilize more glucose and certain amino acids than did lymphocytes obtained from the other two groups. Lymphocytes obtained from the burned-infected group had lower levels of the immunologically important enzyme, adenosine deaminase, than did the lymphocytes obtained from the other two groups. In summary, sepsis appears to alter a number of intracellular lymphocyte metabolic processes. These alterations may be found to be predictive of early sepsis.
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Affiliation(s)
- Y L Dong
- Shriners Burns Institute Galveston Unit, Texas 77550
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191
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Abstract
We studied serum thromboxane (TXB2), the prostacyclin metabolite, 6-keto-PGF1 (6KPGF1) glucose, insulin, and lipid/lipoprotein profiles in 27 patients with non-insulin-dependent diabetes mellitus (NIDDM) who were switched from therapy with glibenclamide (GLB) (with [GLBH] or without phenformin) to gliclazide for 3 months. We found that therapy with gliclazide was followed by a decrease in serum TXB2 (281.8 +/- 128.3 to 149.1 +/- 77.0 mg/L, P less than .001) and an increase in serum 6KPGF1 (60.5 +/- 19.1 to 96.0 +/- 40.3 mg/L, P less than .001). This was accompanied by a decrease in total and low-density lipoprotein (LDL) cholesterol and an increase in high-density lipoprotein (HDL) cholesterol, within the HDL3 cholesterol fraction. These changes were seen despite the fact that neither fasting plasma glucose nor insulin changed with therapy. These findings suggest that gliclazide may have beneficial actions on cardiovascular risk factors in these NIDDM patients.
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Affiliation(s)
- Z Z Fu
- Memorial Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou, People's Republic of China
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192
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Burkhardt H, Yan T, Bröker B, Beck-Sickinger A, Holmdahl R, Von der Mark K, Emmrich F. Antibody binding to a collagen type-II epitope gives rise to an inhibitory peptide for autoreactive T cells. Eur J Immunol 1992; 22:1063-7. [PMID: 1372557 DOI: 10.1002/eji.1830220428] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
It is well documented that antigen recognition by T cells requires small peptides which are generated by protein cleavage in antigen-presenting cells. These peptides have to associate with major histocompatibility complex (MHC) molecules in order to be recognized. An inhibitory peptide may bind to the same site of the MHC-encoded protein but is not recognized by the T cell. Here we describe a stimulatory and an inhibitory peptide sequence within human collagen type II (CII) as defined by means of the same autoreactive human T cell clone. Most interestingly, the inhibitory peptide is not generated by regular processing in peripheral blood mononuclear cells but only in the presence of an antibody that binds to the same domain and thereby seems to protect the inhibitory sequence. This finding may indicate that certain autoantibodies have the potential to block autoreactive T cells with specificity for a distinct epitope on the same antigen.
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Affiliation(s)
- H Burkhardt
- Max-Planck-Gesellschaft, Klinische Arbeitsgruppen für Rheumatologie, Medizinischen Klinik III, Universität Erlangen-Nurnberg, FRG
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193
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Yoshioka M, Fukui M, Hatanaka T, Yan T, Shime N, Tanaka Y. [Usefulness of transcutaneous gas monitoring during hemorrhagic shock]. Masui 1992; 41:238-44. [PMID: 1552663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This study was undertaken to confirm whether transcutaneous (tc) gas analysis during hemorrhagic shock could be used as an alternative to mixed venous gas analysis. Tc gases were measured and correlated with arterial and mixed venous gases in 10 anesthetized dogs during hemorrhagic shock and volume resuscitation. Throughout this experiment PtcO2 correlated well with PvO2 (r = 0.78, P less than 0.01), while PaO2 remained mostly constant, and PtcCO2 correlated well with PvCO2 (r = 0.82, P less than 0.01) rather than with PaCO2 (r = 0.63, P less than 0.01). A more detailed observation showed that during progressively decreased cardiac output, PtcO2 became lower than PvO2 and PtcCO2 became higher than PvCO2. We inferred from these observations that the changes of tc and mixed venous gases reflected those gases in tissues and that during severe shock maldistribution of peripheral blood flow prevented mixed venous gases from coming into equilibrium with tissue and tc gases. We conclude that the measurement of tc gases during shock is a more convenient and more reliable monitor of tissue gases than mixed venous analysis.
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Affiliation(s)
- M Yoshioka
- Department of Anesthesiology, Kyoto Prefectural University of Medicine
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194
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Yan T, Burkhardt H, Ritter T, Bröker B, Mann KH, Bertling WM, von der Mark K, Emmrich F. Specificity and T cell receptor β chain usage of a human collagen type II-reactive T cell clone derived from a healthy individual. Eur J Immunol 1992; 22:51-6. [PMID: 1370417 DOI: 10.1002/eji.1830220109] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Collagen type II (CII) is a cartilage-specific matrix compound well known as an inducer of an experimental, T cell-dependent autoimmune arthritis, a disease which shows some similarities to human rheumatoid arthritis. Here we report on an HLA-DR7-restricted human CD4 T cell clone (TC9), which was isolated from a healthy donor and recognizes human CII. After screening CNBr fragments of CII and tryptic fragments derived thereof, the T cell epitope could be mapped to amino acid residues 271-285 of the triple helical region of CII that are located within CNBr fragment 11 [alpha 1 (II) CB11]. This epitope was confirmed by a synthetic peptide stimulatory for TC9. The T cell receptor beta chain of TC9 was cloned using the polymerase chain reaction; it comprises V beta 6.7 and contains besides J beta 2.3 and C beta 2 an as yet undescribed sequence for the D segment.
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Affiliation(s)
- T Yan
- Clinical Research Unit for Rheumatology, Friedrich-Alexander-Universität, Erlangen-Nürnberg, FRG
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195
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Abstract
Application of N.M.R.
methyl resonance data led to revision of the structures given to the two cis 2,3-diols resulting from osmium tetroxide oxidation of methyl oleana-2,12-dien-28-oate
(10). 2α,3α-Dihydroxyolean-l2-en-28-oic acid (6a), a new natural
product, occurs in Shorea acuminata
resin. Other constituents are 2α-hydroxy-ursolic acid (14a), mangiferonic acid (15b), and asiatic
acid (14c). S. resina-nigra
contains β-amyrin (16a), ursolaldehyde
(14f), and Ψ-taraxesterol(17a).
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