751
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Wang Y, Wang J, Guo H. Effects of inelastic processes on the transmission in a coupled-quantum-wire system. Phys Rev B Condens Matter 1993; 47:4348-4355. [PMID: 10006581 DOI: 10.1103/physrevb.47.4348] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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752
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Yao JH, Guo H. Shadowing instability in three dimensions. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1993; 47:1007-1011. [PMID: 9960099 DOI: 10.1103/physreve.47.1007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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753
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Jörgenson L, Harris R, Grant M, Guo H. Monte Carlo simulation studies of dendritic instabilities in three dimensions. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1993; 47:1235-1242. [PMID: 9960127 DOI: 10.1103/physreve.47.1235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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754
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755
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Abstract
1. It has been reported that catecholamines affect intracellular pH (pHi) in a number of tissues, generally by altering the kinetics of the Na(+)-H+ exchanger. We postulated that catecholamines might affect pHi in cardiac tissue. We tested this in resting sheep cardiac Purkinje fibres by measuring transmembrane potential and pHi with standard and H(+)-sensitive microelectrodes. 2. Adrenaline and the beta-adrenergic agonist isoprenaline, both 5.0 x 10(-6) M, resulted in depolarization and intracellular acidification (adrenaline, 0.03 +/- 0.01 pH units, n = 8, P = 0.005; isoprenaline, 0.08 +/- 0.01 pH units, n = 17, P = 0.0001). The alpha-adrenergic agonist phenylephrine, at concentrations up to 200 microM, had no significant effect on membrane potential or pHi. 3. Isoprenaline significantly attenuated the half-time (t0.5) for pHi recovery from intracellular acidification induced via the NH4Cl pulse technique. Isoprenaline also attenuated the hyperpolarization that is normally seen at the onset of pHi recovery. Phenylephrine slightly reduced the t0.5 for recovery, although the reduction did not reach statistical significance. 4. Forskolin, 7.5-10 x 10(-5) M, an agent that raises intracellular cyclic adenosine 3',5'-monophosphate (cyclic AMP), also induced depolarization and acidification, similar to that induced by adrenaline and isoprenaline. 5. In the presence of the Na(+)-H+ exchange blocker 5-dimethyl amiloride, 2-6 x 10(-5) M, isoprenaline-induced acidification was blunted but not abolished. When administered in Na(+)-free Tyrode solution, isoprenaline-induced acidification was also not abolished. Buffering power, tested using the NH4Cl method, was not decreased by isoprenaline, but rather, was slightly increased. Reversal of H+ driving force across the cell membrane from the normally inward direction to outward (achieved by increasing pHo to 8.3-8.5 and depolarizing the membrane with 10 mM K+ solutions) did not prevent intracellular acidification from occurring in the presence of isoprenaline. When glycolysis was inhibited by a 60 min exposure to glucose-free solution containing 5.5 mM 2-deoxyglucose, acidification by isoprenaline was nearly abolished. 6. We conclude that, in resting sheep Purkinje fibres, beta- but not alpha-adrenergic stimulation results in intracellular acidification and depolarization, probably mediated via an increase in cyclic AMP. beta- but not alpha-adrenergic stimulation slows the rate of recovery from intracellular acidification and blunts the hyperpolarization associated with this recovery. 7. The intracellular acidification appears to be due both to partial inhibition of Na(+)-H+ exchange and to stimulation of glycolysis by beta-adrenergic agents.
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Affiliation(s)
- H Guo
- Reingold ECG Center (Division of Cardiology, Department of Medicine), Northwestern University Medical School, Chicago, IL 60611-3008
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756
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Liu FS, Guo H. [Application of electron microscopy in the diagnosis of neoplasms]. Zhonghua Bing Li Xue Za Zhi 1992; 21:272-4. [PMID: 1291148] [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: 12/26/2022]
Abstract
The majority of neoplasms can be diagnosed by light microscopy, but in some cases the diagnosis remains ambiguous due to poor differentiation, even though special stainings have been employed. This paper presents 34 cases of neoplasms in which the tumors were diagnosed by electron microscopy. This includes distinguishing (1) anaplastic carcinoma from lymphoma; (2) anaplastic carcinoma from amelanotic melanoma; (3) APUDoma from other tumors; (4) different mesenchymal tumors. The diagnoses of 4 cases of malignant melanoma, 11 cases of APUDoma, 7 cases of poorly differentiated carcinoma or anaplastic carcinoma, 2 cases of non-Hodgkin's lymphoma, 9 cases of mesenchymal tumors and 1 cases of other tumors have been resolved by electron microscopy. It is obvious that in some cases, electron microscopy can be of help in establishing a correct diagnosis.
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Affiliation(s)
- F S Liu
- Department of Pathology, Chinese Academy of Medical Sciences, Beijing
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757
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Guo H, Acevedo P, Parsa FD, Bertram JS. Gap-junctional protein connexin 43 is expressed in dermis and epidermis of human skin: differential modulation by retinoids. J Invest Dermatol 1992; 99:460-7. [PMID: 1328400 DOI: 10.1111/1523-1747.ep12616154] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.9] [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: 12/26/2022]
Abstract
Retinoids are effective modulators of proliferation and differentiation of keratinocytes in vivo and in vitro. In mouse 10T1/2 cells, retinoid action on proliferation and neoplastic transformation is correlated with the upregulation of gap-junctional communication and expression of connexin 43 (Cx43). In the present study we have determined if retinoids induce similar effects on gene expression in human skin. Studies were conducted in intact skin and on cultured keratinocytes and dermal fibroblasts. In a clinical study, 2 weeks of treatment with 0.05% all-trans retinoic acid resulted in increased expression of Cx43 mRNA and protein in epidermis. Expression occurred predominantly in the suprabasal layer. Cultured cells exhibited a differential response to retinoic acid. In keratinocytes, increased expression of Cx43 occurred at low (10(-11) M) concentrations, whereas inhibition occurred at high (10(-7) M) concentrations; however, junctional communication, measured by dye transfer, was not altered over this concentration range. Dermal fibroblasts, in contrast, exhibited a dose-dependent increased expression of Cx43 at concentrations up to 10(-7) M retinoic acid and proportionately increased their junctional communication over this dose range. These data indicate that control of Cx43 gene expression by retinoids in human skin cells is complex. The production of gradients of junctional channels could play a role in the control of growth and differentiation in epidermis.
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Affiliation(s)
- H Guo
- Molecular Oncology Program, Cancer Research Center of Hawaii, University of Hawaii, Honolulu 96813
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758
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Carmel Y, Lou WR, Rodgers J, Guo H, Destler WW, Granatstein VL, Levush B, Antonsen T, Bromborsky A. From linearity towards chaos: Basic studies of relativistic backward-wave oscillators. Phys Rev Lett 1992; 69:1652-1655. [PMID: 10046279 DOI: 10.1103/physrevlett.69.1652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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759
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760
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Guo H, Chang S. Posterior chamber IOL implantation in traumatic cataract with injured complications. Yan Ke Xue Bao 1992; 8:111-2, 125. [PMID: 1303866] [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: 12/26/2022]
Abstract
Twenty-five cases of posterior chamber IOL implantation in traumatic cataract with complications associated with primary injury were reported. The operating methods were described and the post-operative complications were discussed. Seventy-two percent of patients have the correct vision over 20/40. It is suggested that the posterior chamber IOL can be implanted in traumatic cataract with some injured complications.
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Affiliation(s)
- H Guo
- Department of Ophthalmology, First Teaching Hospital, Henan Medical University, Zhengzhou, China
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761
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Wu K, Li S, Chen S, Guo H. Comparative studies of the carbohydrate of human gamma-crystallins from fetal and adult lenses with agglutinins. Yan Ke Xue Bao 1992; 8:108-10. [PMID: 1303865] [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: 12/26/2022]
Abstract
Using gel chromatography of Sephadex G-75 superfine connected with Sephadex G-50 fine column, three human gamma-crystallins (gamma 1, gamma 2, gamma 3) could be obtained. Seven agglutinins (LCA, SBA, DBA, PNA, BSL, RCA and UEA) were used to detect the sugar of sub-gamma-crystallins, which had been transferred to nitrocellulose membrane and finally stained with ABC reagents and the substrate of HPR. These results suggested that gamma 2- and gamma 3-crystallins contain sugar, but gamma 1-crystallin has no sugar. There is a decrease of carbohydrate of gamma 2 and gamma 3 as the development of the lens (esp. the former). It was postulated that in gamma-crystallins (gamma 2, gamma 3) the sugar components helped stabilizing the molecular structure (folding polypeptide, prevent protein breaking). The sugar components decreased with age by the post-translation modification.
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Affiliation(s)
- K Wu
- National Ophthalmological Laboratories, Ministry of Public Health, China
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762
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Guo H, Hong DC, Kurtze DA. Dynamics in pattern-forming systems. Phys Rev A 1992; 46:1867-1874. [PMID: 9908323 DOI: 10.1103/physreva.46.1867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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763
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Wang J, Wang YJ, Guo H. Ballistic-electron transport through a coupled-quantum-wire system. Phys Rev B Condens Matter 1992; 46:2420-2427. [PMID: 10003916 DOI: 10.1103/physrevb.46.2420] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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764
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Sekiguchi M, Shimai K, Guo H, Nowakowski RS. Cytoarchitectonic abnormalities in hippocampal formation and cerebellum of dreher mutant mouse. Brain Res Dev Brain Res 1992; 67:105-12. [PMID: 1638738 DOI: 10.1016/0165-3806(92)90030-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The laminated structures in the hippocampal formation and cerebellum of homozygous dreher mice were compared to their littermates and to C57BL/6J mice in Nissl- and myelin-stained preparations. In the dreher dentate gyrus, ectopic granule cells were situated in the molecular layer, and frequently there was either partial or complete absence of the infrapyramidal limb of the granule cell layer. In the dreher hippocampus, the cells of the pyramidal cell layer in area CA3 formed widely dispersed arrangements, and there were ectopically situated pyramidal cells in the stratum radiatum and stratum oriens. In the dreher cerebellum, 3 abnormal patterns were observed: (1) disruptions of foliation with normal cytoarchitectonic structure, (2) foliation with a mixture of normal laminated structure and abnormal laminated structure, and (3) almost complete absence of the cerebellum. In abnormal folia exhibiting the second or third pattern, islands consisting of agglomerations of both granule cells and Purkinje cells or just granule cells were observed. The neuronal heterotopias and cytoarchitectonic disorganization observed in the present study are apparently secondary to disruption of cell proliferation and neuronal migration produced directly or indirectly by the dreher mutation. In addition, the fact that the phenotypic abnormalities in homozygous dreher mice produces different abnormal morphologies in different specimens may be useful for analyzing the development of the hippocampal formation and cerebellum.
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Affiliation(s)
- M Sekiguchi
- Department of Anatomy, Tokai University School of Medicine, Kanagawa, Japan
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765
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Zhang Z, Laradji M, Guo H, Mouritsen OG, Zuckermann MJ. Phase behavior of pure lipid bilayers with mismatch interactions. Phys Rev A 1992; 45:7560-7567. [PMID: 9906830 DOI: 10.1103/physreva.45.7560] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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766
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Guo H, Sekiguchi M, Shimai K. Cytoarchitectonic abnormalities in cerebellum and hippocampal formation of beige mutant mouse. Tokai J Exp Clin Med 1992; 17:53-61. [PMID: 1523694] [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
Abnormalities in the cerebellum and hippocampal formation of the beige mouse were revealed by histological and immunohistochemical examination. In the cerebellum, Purkinje cells and clusters of granule cells, plus an occasional Bergmann glia cell, were located ectopically in the molecular layer. In the hippocampus, ectopically situated pyramidal cell were found in the stratum oriens of area CA3. The infrapyramidal mossy fiber layer (IPMFL) was formed by fiber bundles emerging from two districtly separated areas of the dentate gyrus. The IMPFL was not compact, but appeared as clumps of scattered fiber bundles. The neuronal heterotopias and cytoarchitectonic disorganization observed in the beige mutant mouse cerebellum and hippocampus may prove to be very useful parameters in analyzing the relationship between the immune system and the development of the central nervous system.
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Affiliation(s)
- H Guo
- Department of Anatomy, Tokai University School of Medicine, Kanagawa, Japan
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767
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768
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769
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Guo H, Lorenz RR, Vanhoutte PM. Anisodamine antagonizes acetylcholine-induced inhibition of adrenergic neurotransmission in the canine saphenous vein. Chin Med Sci J 1992; 7:32-5. [PMID: 1330075] [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: 12/26/2022]
Abstract
The effect of anisodamine, an alkaloid structurally related to atropine and isolated from a Chinese herb, on adrenergic neurotransmission was studied using isolated canine saphenous veins. Helical strips of vein were incubated in modified physiological salt solution containing L-(7- 3H)-norepinephrine (3 x 10(-7) mol/L) for two hours and then mounted for isometric tension recording and superfusion. Increases in isometric tension and efflux of total tritiated compounds and 3H-norepinephrine evoked by electrical stimulation were inhibited by acetylcholine (10(-6) mol/L). This effect of acetylcholine was antagonized to comparable levels by anisodamine (10(-6) mol/L) or atropine (10(-6) mol/L). The results demonstrate that anisodamine blocks prejunctional muscarinic receptors.
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Affiliation(s)
- H Guo
- Institute of Basic Medical Sciences, CAMS, Beijing
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770
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Thomson JR, Guo H, Ryan DH, Zuckermann MJ, Grant M. Magnetic ordering in the three-dimensional frustrated Heisenberg model. Phys Rev B Condens Matter 1992; 45:3129-3132. [PMID: 10001871 DOI: 10.1103/physrevb.45.3129] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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771
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Affiliation(s)
- H Guo
- Sch. of Electr. Eng., Purdue Univ., West Lafayette, IN
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772
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Bertram JS, Hozzain MZ, Zhang LX, Guo H. 93. Retinoids up-regulate expression of connexion 43 in human and mouse cells: implication for growth control and differentiation. Pharmacotherapy 1992. [DOI: 10.1016/0753-3322(92)90178-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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773
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Laradji M, Guo H, Grant M, Zuckermann MJ. Phase diagram of a lattice model for ternary mixtures of water, oil, and surfactants. Phys Rev A 1991; 44:8184-8188. [PMID: 9905970 DOI: 10.1103/physreva.44.8184] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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774
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Lin T, Guo H, Calkins JH, Wang D, Chi R. Recombinant monocyte-derived interleukin-1 receptor antagonist reverses inhibitory effects of interleukin-1 on Leydig cell steroidogenesis. Mol Cell Endocrinol 1991; 78:205-9. [PMID: 1838083 DOI: 10.1016/0303-7207(91)90124-b] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Previously we have reported that interleukin-1 (IL-1) is a potent inhibitor of Leydig cell function. Most recently, IL-1 receptor antagonist (IL-1ra) has been purified, sequenced and cloned. In the present study, we evaluated the recombinant monocyte-derived IL-1ra on the inhibitory effects of IL-1. The addition of recombinant human IL-1ra up to 1000 ng/ml has no discernible effects on human chorionic gonadotropin (hCG)-stimulated testosterone formation in primary cultures of rat Leydig cells. Similar to that reported previously, IL-1 beta caused a dose-dependent inhibition of hCG-induced testosterone. The inhibitory effect of IL-1 beta could be reversed by the concomitant addition of IL-1ra. The amounts of IL-1ra required to reverse the effect of IL-1 were 25-fold higher. Our results suggest that IL-1 is important in modulating Leydig cell function and its effect most likely is mediated by specific IL-1 receptors.
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Affiliation(s)
- T Lin
- Medical Services, W.J.B. Dorn Veterans Hospital, Columbia, SC 29201
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775
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776
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777
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Van Speybroeck R, Guo H, Van der Eycken J, Vandewalle M. Enantioselective total synthesis of (−)-epipodophyllotoxin and (−)-podophyllotoxin. Tetrahedron 1991. [DOI: 10.1016/s0040-4020(01)86473-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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778
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779
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Marshall TK, Guo H, Price DH. Drosophila RNA polymerase II elongation factor DmS-II has homology to mouse S-II and sequence similarity to yeast PPR2. Nucleic Acids Res 1990; 18:6293-8. [PMID: 2243775 PMCID: PMC332494 DOI: 10.1093/nar/18.21.6293] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [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: 12/30/2022] Open
Abstract
DmSII is a Drosophila RNA polymerase II elongation factor which suppresses pausing by RNA polymerase II at specific sites on double stranded templates. Using antibodies produced against the purified protein, a Drosophila cDNA expression library was screened and a cDNA was isolated which encoded a portion of DmSII. When this cDNA was used to probe Kc cell mRNA the predominant species was found to be 1.4 kb in length. The original cDNA was used to screen a Drosophila Kc cell cDNA library resulting in the isolation of a 1.4 kb cDNA which was then sequenced. The deduced protein sequence for DmSII exhibited high similarity to mouse SII protein sequence. In addition, significant sequence similarity was found with the protein encoded by the yeast gene PPR2, which is involved in regulation of URA4 gene expression. The comparison of amino acid sequences suggests that DmSII is comprised of two domains homologous to mouse SII separated by a flexible, serine rich region of low homology. The shorter yeast protein has sequence similarity only to the carboxy terminal domain.
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Affiliation(s)
- T K Marshall
- Department of Biochemistry, University of Iowa, Iowa City 52242
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780
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Abstract
In the present study, we evaluated insulin-like growth factor-I (IGF-I) messenger RNA expression in the rat testis. Crude interstitial cells were separated into three distinct bands on 15-60% Percoll density gradients. IGF-I mRNA was mainly localized in the Leydig cell-enriched fraction (band 3), while band 1 and band 2 cells did not contain significant amounts of IGF-I mRNA. Leydig cell IGF-I mRNA consisted of multiple species varying from 0.8 to 7.5 kb and was present in rat Leydig cells all ages examined, from 25 to 55 days old. To further document that IGF-I mRNAs are present in Leydig cells, the method of Klinefelter et al. (Biol. Reprod. (1987) 36, 769-783) was used to isolate highly purified (greater than 98% pure) Leydig cells. Most of the IGF-I mRNA was localized in these Leydig cells, while there was no detectable IGF-I mRNA in the whole testis or other interstitial cells. Furthermore, IGF-I mRNA in Leydig cells was increased more than 2-fold by growth hormone (GH) administration in vivo. This suggests that IGF-I mRNA in Leydig cells is also GH dependent. Interstitial IGF-I produced in Leydig cells may have both autocrine and paracrine effects in the testis.
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Affiliation(s)
- T Lin
- Medical Service, W.J.B. Dorn Veterans Hospital, Columbia, SC 29201
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781
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Abstract
Interstitial tissue of the testis consists of Leydig cells, macrophages, lymphocytes, plasma cells, mast cells and fibroblasts. Previously we have reported that interleukin-1 (IL-1) inhibits Leydig cell androgen production. In the present study, the effect of IL-2 was investigated. Leydig cells (10(5) cells/ml) from adult Sprague-Dawley rats were cultured with or without IL-2 for 24 h. After medium changes, human CG (hCG), 8-bromo-cAMP, or forskolin was added with or without IL-2. Cultures were continued for an additional 24 h, and testosterone and cAMP levels were measured. IL-2 up to 100 U/ml had no effect on basal testosterone production. hCG-stimulated testosterone formation was inhibited in a dose-dependent manner by the addition of IL-2. IL-2 in a concentration of 100 U/ml decreased hCG-induced testosterone formation from 49.6 +/- 3.6 ng/ml (mean +/- SE) to 8.5 +/- 4.2 ng/ml. The hCG dose-response curve was shifted to the right by the addition of IL-2. Maximal testosterone production in response to hCG was reduced 40% in the presence of IL-2 (50 U/ml) without alteration of median effective dose (ED50). IL-2 also inhibited hCG-induced cAMP formation and 8-bromo cAMP- and forskolin-stimulated testosterone production. However, IL-2 did not alter the binding of [125I]hCG to purified Leydig cells. Furthermore, IL-2 significantly inhibited the conversion of 20-OH-cholesterol, 22-OH-cholesterol, pregnenolone, progesterone, 17 alpha-hydroxypregnenolone, and 17 alpha-hydroxyprogesterone to testosterone but did not alter the conversion of dehydroepiandrosterone and androstenedione to testosterone. Our results suggest that a T cell growth factor, IL-2, is a potent inhibitor of steroidogenesis. IL-2 may play a paracrine role in modulating Leydig cell function.
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Affiliation(s)
- H Guo
- Medical Service, WJB Dorn Veterans' Hospital, Columbia, South Carolina 29201
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782
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Kass SR, Guo H, Dahlke GD. The thiomethyl anion: Formation, reactivity, and thermodynamic properties. J Am Soc Mass Spectrom 1990; 1:366-371. [PMID: 24248898 DOI: 10.1016/1044-0305(90)85016-f] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/1990] [Accepted: 04/10/1990] [Indexed: 06/02/2023]
Abstract
The thiomethyl anion (1) has been generated by fluorodesilylation of trimethylsilylmethanethiol in a variable-temperature flowing afterglow device. The proton affinity (1649 ± 12 kJ mol(-1)) and electron affinity (0.67 ± .13 eV) were determined and compared to a previously reported molecular orbital calculation. Isomerization via a 1,2-proton shift does not take place between -40° and 100°C despite a 156 kJ mol(-1) driving force. Ion-molecule reactions of 1 were examined with a number of reagents including N20, O2, CS2, COS, and CO2, Hydride ion transfer was observed in every case, along with other products, and thermodynamic information has been derived.
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Affiliation(s)
- S R Kass
- Department of Chemistry, University of Minnesota, 55455, Minneapolis, MN
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783
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784
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Grossmann B, Guo H, Grant M. Monte Carlo renormalization-group study of self-organized criticality. Phys Rev A 1990; 41:4195-4198. [PMID: 9903613 DOI: 10.1103/physreva.41.4195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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785
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786
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Abstract
Previously we have reported that human chorionic gonadotropin(hCG)-stimulated testosterone biosynthesis was markedly inhibited by purified natural human interleukin-1 (IL-1). In the present study we evaluated the effects of human and murine recombinant IL-1 (rIL-1) on Leydig cell steroidogenesis in primary culture. Human rIL-1 beta caused a dose-dependent inhibition of hCG-, 8-bromo cyclic AMP-, and forskolin-induced testosterone formation. In contrast, human rIL-1 alpha was considerably less potent. When the effects of the cytokines were corrected for their biological potencies, human rIL-1 beta and murine rIL-1 alpha were still more effective than human rIL-1 alpha in inhibiting testosterone production (at least 100-fold more potent). Thus, even though IL-1 alpha and IL-1 beta bind to the same receptors on T cells, Leydig cells exhibit differential sensitivity in response to rIL-1 alpha and rIL-1 beta which is partly species dependent.
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Affiliation(s)
- J H Calkins
- Medical and Research Services, WJB Dorn Veterans Hospital, Columbia, South Carolina
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787
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Guo H, Hong DC. Random-walk simulation of the solvability theory for the Saffman-Taylor problem. Phys Rev A 1990; 41:2995-2998. [PMID: 9903449 DOI: 10.1103/physreva.41.2995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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788
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789
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Calkins JH, Guo H, Sigel MM, Lin T. Tumor necrosis factor-alpha enhances inhibitory effects of interleukin-1 beta on Leydig cell steroidogenesis. Biochem Biophys Res Commun 1990; 166:1313-8. [PMID: 2154976 DOI: 10.1016/0006-291x(90)91009-h] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [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: 12/30/2022]
Abstract
Human recombinant tumor necrosis factor-alpha (rTNF alpha) alone (up to 1000 units/ml) did not alter either basal or human chorionic gonadotropin (hCG)-induced testosterone formation in primary culture of rat Leydig cells. However, concomitant addition of rTNF alpha with human recombinant interleukin-1 beta (rIL-1 beta) enhanced the inhibitory effects of rIL-1 beta. The rIL-1 beta dose response curve was shifted to the left (IC50 changed from 1 ng/ml to 0.3 ng/ml). Even though rTNF alpha had no effect on testosterone formation, hCG-stimulated cyclic AMP formation was inhibited by rTNF alpha in a dose dependent manner. In the presence of both rTNF alpha and rIL-1 beta, hCG-induced cyclic AMP formation and binding of [125I]-hCG to Leydig cells were further inhibited. Testicular macrophages represent about 20% of the interstitial cells. TNF alpha and IL-1 may be produced locally by interstitial macrophages and have paracrine effects on Leydig cell function.
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Affiliation(s)
- J H Calkins
- Medical and Research Service, WJB Dorn Veterans' Hospital, Columbia, SC 29201
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790
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791
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Hernández-Machado A, Guo H, Mozos JL, Jasnow D. Interfacial growth in driven diffusive systems. Phys Rev A Gen Phys 1989; 39:4783-4788. [PMID: 9901830 DOI: 10.1103/physreva.39.4783] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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792
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Zheng Q, Guo H, Gunton JD. Growth of breath figures and a possible relationship with ultradynamics. Phys Rev A Gen Phys 1989; 39:3181-3184. [PMID: 9901614 DOI: 10.1103/physreva.39.3181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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793
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Zheng Q, Guo H, Gunton JD. Finite-size scaling theory for domain growth in the time-dependent Ginzburg-Landau model: Layered system. Phys Rev B Condens Matter 1989; 39:4563-4567. [PMID: 9948807 DOI: 10.1103/physrevb.39.4563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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794
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Guo H, Jasnow D. Erratum: Hyperuniversality and the renormalization group for finite systems. Phys Rev B Condens Matter 1989; 39:753. [PMID: 9949139 DOI: 10.1103/physrevb.39.753] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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795
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Affiliation(s)
- R G Chen
- Shanghai Institute for Pediatric Research, Shanghai Second Medical University, China
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796
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Guo H, Zheng Q, Gunton JD. Finite-size scaling theory for domain growth in the time-dependent Ginzburg-Landau model. Phys Rev B Condens Matter 1988; 38:11547-11549. [PMID: 9946036 DOI: 10.1103/physrevb.38.11547] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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797
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Braga J, Guo H, Murrell J, Dunne L. A comparative study of quantum mechanical and classical trajectory calculations for anA+BCcollinear non-adiabatic collision. Mol Phys 1988. [DOI: 10.1080/00268978800101491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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798
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799
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800
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Farrar JM, Bowers MT, Leone SR, Gislason EA, Murrell JN, Braga JP, Dunne LJ, Guo H, Clary DC, Varandas AJC, Smith IWM, Rubahn HG, Sathyamurthy N, Toennies JP. General discussion. ACTA ACUST UNITED AC 1987. [DOI: 10.1039/dc9878400351] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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