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Wen XH, Wang XH, Tong JS, Yang ZW, Zhang GY. Reversible effect of testosterone undecanoate injection on spermatogenesis in rats. Asian J Androl 2000; 2:207-11. [PMID: 11225979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
AIM To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. METHODS Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60 days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of 120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminiferous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereological methods as a measure of the spermatogenic efficiency. RESULTS Low dose (8 mg/kg) TU treatment virtually had no effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and severe suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of the recovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well tolerated by animals. CONCLUSION TU injection reversibly suppresses spermatogenesis in rats.
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Yang ZW, Wang J, Zheng T, Altura BT, Altura BM. Low [Mg(2+)](o) induces contraction of cerebral arteries: roles of tyrosine and mitogen-activated protein kinases. Am J Physiol Heart Circ Physiol 2000; 279:H185-94. [PMID: 10899055 DOI: 10.1152/ajpheart.2000.279.1.h185] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study was designed to investigate the mechanism of action of low extracellular magnesium ion concentration ([Mg(2+)](o)) on isolated canine basilar arteries and single cerebral vascular smooth muscle cells from these arteries. Low-[Mg(2+)](o) medium (0-0.6 mM) produces endothelium-independent contractions in isolated canine basilar arteries in a concentration-dependent manner; the lower the concentration of [Mg(2+)](o), the stronger the contractions. The low-[Mg(2+)](o) medium-induced contractions are significantly attenuated by pretreatment of the arteries with low concentrations of either SB-203580, U-0126, PD-98059, genistein, or an Src homology 2 (SH2) domain inhibitor peptide. IC(50) levels obtained for these five antagonists are consistent with reported inhibitor constant (K(i)) values for these tyrosine kinase and mitogen-activated protein kinase (MAPK) antagonists. Low-[Mg(2+)](o) medium (0-0.6 mM) produces transient intracellular calcium ion concentration ([Ca(2+)](i)) peaks followed by a slow, sustained, and elevated plateau of [Ca(2+)](i) in primary single smooth muscle cells from canine basilar arteries. Low-[Mg(2+)](o) medium induces rapid and stable increases in [Ca(2+)](i); these increases are inhibited markedly in the presence of either SB-203580, U-0126, PD-98059, genistein or a SH2 domain inhibitor peptide. Several specific antagonists of known endogenously formed vasoconstrictors do not inhibit or attenuate either the low-[Mg(2+)](o)-induced contractions or the elevation of [Ca(2+)](i). The present study suggests that activation of several cellular signaling pathways, such as protein tyrosine kinases (including the Src family) and MAPK, appears to play important roles in low-[Mg(2+)](o)-induced contractions and the elevation of [Ca(2+)](i) in smooth muscle cells from canine basilar arteries.
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Yang ZW, Gebrewold A, Nowakowski M, Altura BT, Altura BM. Mg(2+)-induced endothelium-dependent relaxation of blood vessels and blood pressure lowering: role of NO. Am J Physiol Regul Integr Comp Physiol 2000; 278:R628-39. [PMID: 10712282 DOI: 10.1152/ajpregu.2000.278.3.r628] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In vitro extracellular Mg(2+) concentration ([Mg(2+)](0)) produces endothelium-dependent and endothelium-independent relaxations in rat aorta in a concentration-dependent manner. These relaxant effects of Mg(2+) on intact rat aortic rings, but not denuded rat aortic rings, were suppressed by either N(G)-monomethyl-L-arginine (L-NMMA), N(omega)-nitro-L-arginine methyl ester (L-NAME), or methylene blue. The inhibitory effects of L-NMMA and L-NAME could be reversed partly by L-arginine. [Mg(2+)](0)-induced dilatation in vivo in rat mesenteric arterioles and venules was almost completely inhibited by N(G)-nitro-L-arginine and L-NMMA. Removal of extracellular Ca(2+) concentration ([Ca(2+)](0)) or buffering intracellular Ca(2+) concentration in endothelial cells, with 10 microM 1, 2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-AM, markedly attenuated the relaxant effects of Mg(2+). Mg(2+) produced nitric oxide (NO) release from the intact aortic rings in a concentration-dependent manner. Removal of [Ca(2+)](0) diminished the increased NO release induced by elevated levels of [Mg(2+)](0). In vivo infusion of increasing doses (1-30 microM/min) of MgSO(4), directly into the femoral veins of anesthetized rats, elicited significant concentration-dependent sustained increases in serum total Mg and concomitant decreases in arterial blood pressure. Before and after employment of various doses of MgSO(4), intravenous administration of either L-NMMA (10 mg/kg) or L-NAME (10 mg/kg) increased (i.e., reversed) the MgSO(4)-lowered blood pressure markedly, and intravenous injection of L-arginine restored partially the increased blood pressure effects of both L-NMMA and L-NAME. Our results suggest that 1) small blood vessels are very dependent on NO release for Mg(2+) dilatations and 2) the endothelium-dependent relaxation induced by extracellular Mg(2+) is mediated by release of endothelium-derived relaxing factor-NO from the endothelium, and requires Ca(2+) and formation of guanosine 3',5'-cyclic monophosphate.
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Wen XH, Yang ZW. Quantitative (stereological) study on the spermatozoal storage capacity of epididymis in rats and monkeys. Asian J Androl 2000; 2:73-7. [PMID: 11228941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
AIM To investigate the spermatozoal production rate of the testis and the spermatozoal storage capacity of the epididymis in monkeys and rats. METHODS The number of the late spermatids (steps 13-14 in the monkey or steps 15-19 in the rat) per testis and the number of spermatozoa per epididymis were estimated in 6 normal adult monkeys (Macaca fascicularis) and 6 normal adult SD rats on 25 microns-thick methacrylate-embedded sections using a contemporary unbiased and efficient stereological method--the optical disector. The diameter and length of the efferent ductules and ductus epididymidis and the volume of the epididymal fluid in the tubules were also estimated. RESULTS The total number of the late spermatids per testis was 2902 +/- 749 (million, x +/- s) in the monkey, or 179 +/- 31 in the rat; the number of spermatozoa per epididymis was 3235 +/- 1835 in the monkey, or 241 +/- 76 in the rat. CONCLUSION A large number of spermatozoa was densely packed and stored in the ductus epididymidis; the epididymal transit time for spermatozoa was around 5 days in monkeys or 11 days in rats.
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Yang ZW, Zheng T, Wang J, Zhang A, Altura BT, Altura BM. Hydrogen peroxide induces contraction and raises [Ca2+]i in canine cerebral arterial smooth muscle: participation of cellular signaling pathways. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1999; 360:646-53. [PMID: 10619181 DOI: 10.1007/s002109900128] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effects of hydrogen peroxide (H2O2) on isolated canine basilar arteries, and single smooth muscle cells isolated from these arteries, were investigated in the present study. Exposure of isolated endothelium-intact and denuded arterial rings to H2O2, at concentrations of 2.2x10(-5) M to 4.4x10(-3) M, produced concentration-dependent contractile responses. Removal of the endothelium attenuated, but did not eliminate the contractions. H2O2-induced contractions were inhibited, to different degrees, by preincubation of the vessels with low concentrations of staurosporine or bisindolylmaleimide I HCl [antagonists of protein kinase C (PKC)], Gö6976 (a PKCalpha and PKCbeta1 selective antagonist), genistein (an antagonist of protein tyrosine kinase), PD-98059 (an antagonist of mitogen-activated protein kinase), wortmannin [an antagonist of phosphatidylinositol 3 (PI3)-kinases], and LY-294002 (an antagonist of PI3-kinases). These agents were also found to relax arteries precontracted by H2O2. Removal of extracellular Ca2+ or pretreatment of the vessels with 5.0 microM verapamil markedly attenuated the contractions. Complete inhibition of the contractile response was obtained after buffering intracellular Ca2+ with BAPTA-AM. A variety of specific pharmacological antagonists of several known vasoconstrictors neither inhibited nor attenuated the H2O2-induced contractions. Exposure of smooth muscle cells to H2O2 (4.4x10(-6) M to 4.4x10(-4) M) significantly raised intracellular Ca2+ ([Ca2+]i) within 20 s. This was abolished in the absence of extracellular Ca2+ or after application of 5.0 microM verapamil. Pretreatment of the cells with low concentrations of staurosporine, bisindolylmaleimide I, Gö6976, genistein, PD-98059, wortmannin, and LY-294002 markedly suppressed the H2O2-mediated [Ca2+]i elevation. The present findings suggest that hydrogen peroxide, in vitro, produces endothelium-dependent and independent contractions of canine basilar arteries, which are clearly Ca2+-dependent and are not associated with release of endogenous vasoconstrictors. Several intracellular signal transduction systems, such as PKC (both Ca2+-dependent and Ca2+-independent), protein tyrosine phosphorylation, IP3, mitogen-activated protein kinase and PI3 kinase appear to play a role in the H2O2-induced contractions in cerebral arterial muscle.
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Yang ZW, Altura BT, Altura BM. Low extracellular Mg2+ contraction of arterial muscle: role of protein kinase C and protein tyrosine phosphorylation. Eur J Pharmacol 1999; 378:273-81. [PMID: 10493103 DOI: 10.1016/s0014-2999(99)00474-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The effects of extracellular Mg2+ ion ([Mg2+]0) deficiency on basal tension of isolated rat aortae and rat aortic smooth muscle cell Ca2+ metabolism were investigated in the present study. The contractions of rat aortae induced by diverse concentrations of low [Mg2+]0 were potentiated, greatly, by removal of the endothelium or pre-incubation of intact rat aortic rings with L-N(G)-monomethyl-arginine (L-NMMA). [Mg2+]0 deficiency-induced contractions were inhibited, to different degrees, by pre-treatment of the vessels with low concentrations of Gö6976, bisindolymaleimide I, genistein or a combination of bisindolymaleimide I with genistein. IC50 levels found for these three agents were found to be not too different from Ki values for these drugs. Pre-treatment of rat aortic smooth muscle cells with Gö6976, bisindolymaleimide I, genistein or a combination of bisindolymaleimide I with genistein suppressed, significantly, or almost eliminated both the rapid and stable increments in [Ca2+]i induced by Mg2+-free medium. The present findings suggest that both protein kinase C and protein tyrosine phosphorylation appear to play important roles in Mg2+ deficiency-induced contractions of isolated rat aortic smooth muscle, most likely via phosphorylation of L-type Ca2+ channels.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiology
- Arteries/drug effects
- Arteries/physiology
- Calcium/metabolism
- Carbazoles/pharmacology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/physiology
- Enzyme Inhibitors/pharmacology
- Genistein/pharmacology
- In Vitro Techniques
- Indoles/pharmacology
- Magnesium/pharmacology
- Male
- Maleimides/pharmacology
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Phosphoproteins/metabolism
- Phosphorylation
- Phosphotyrosine/metabolism
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/physiology
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Rats
- Rats, Wistar
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Peng A, Wang WH, Wang CX, Wang ZJ, Rui HF, Wang WZ, Yang ZW. The role of humic substances in drinking water in Kashin-Beck disease in China. ENVIRONMENTAL HEALTH PERSPECTIVES 1999; 107:293-6. [PMID: 10090708 PMCID: PMC1566521 DOI: 10.1289/ehp.99107293] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We conducted in vitro and in vivo assays in a selenium-deficient system to determine if organic matter (mainly fulvic acid; FA) is involved in a free radical mechanism of action for Kashin-Beck disease. Cartilage cell culture experiments indicated that the oxy or hydroxy functional groups in FA may interfere with the cell membrane and result in enhancement of lipid peroxidation. Experiments with rats demonstrated that toxicity from FA was reduced when the hydroxy group was blocked. Induction of lipid peroxidation by FA in liver and blood of rats was similar to that exhibited by acetyl phenyl hydrazine. FA accumulated in bone and cartilage, where selenium rarely concentrates. In addition, selenium supplementation in rats' drinking water inhibited the generation of oxy-free radicals in bone. We hypothesized that FA in drinking water is an etiological factor of Kashin-Beck disease and that the mechanism of action involves the oxy and hydroxy groups in FA for the generation of free radicals. Selenium was confirmed to be a preventive factor for Kashin-Beck disease.
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Yang ZW, Zhang A, Altura BT, Altura BM. Endothelium-dependent relaxation to hydrogen peroxide in canine basilar artery: a potential new cerebral dilator mechanism. Brain Res Bull 1998; 47:257-63. [PMID: 9865858 DOI: 10.1016/s0361-9230(98)00120-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In prostglandin F2alpha(PGF2alpha)-precontracted isolated canine basilar arterial rings, hydrogen peroxide (H2O2) produced endothelium-dependent relaxations at concentrations of from 4.4 x 10(-7) - approximately 4.4 x 10(-5) M. Removal of extracellular Ca2+ ([Ca2+]0) attenuated the relaxant effects of H2O2. Complete inhibition of H2O2 relaxant action was obtained after buffering intracellular Ca2+ ([Ca2+]i), in the endothelial cells, with 10 microM 1,2-bis (2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM). The H2O2-induced relaxations could be abolished completely by 1200 u/ml catalase and was suppressed significantly by 0.5 microM atropine, 150 microM NG-monomethyl-arginine (L-NMMA), 50 microM NG-nitro-L-arginine methyl ester (L-NAME), 1 microM Fe2+, or 5 microM methylene blue. These inhibitory effects of L-NMMA, L-NAME, or atropine could be reversed partly by 50 microM L-arginine. The Fe2+ inhibition of H2O2-stimulated relaxation was reduced significantly by either 1 mM deferoxamine (a Fe2+ chelator) or 100 microM dimethyl sulfoxide (DMSO, a *OH scavenger). Such relaxant effects of H2O2 were enhanced, significantly, by an acetylcholinesterase antagonist, neostigmine. A variety of pharmacological antagonists (of diverse vasodilator agents) could not inhibit the relaxant action of H2O2. Our observations suggest that at suitable pathophysiological concentrations, H2O2 could induce release of an endothelium-derived relaxing factor (EDRF), probably nitric oxide (NO), from endothelial cells of the canine cerebral artery. The H2O2 relaxant effects are clearly Ca2+-dependent, require formation of cyclic guanosine monophosphate (cGMP), and may be associated with release of endogenous acetylcholine (ACh).
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Yang ZW, Zheng T, Zhang A, Altura BT, Altura BM. Mechanisms of hydrogen peroxide-induced contraction of rat aorta. Eur J Pharmacol 1998; 344:169-81. [PMID: 9600652 DOI: 10.1016/s0014-2999(97)01576-8] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
It has been suggested that reactive oxygen species may be involved in the regulation of vascular tone. However, the underlying mechanisms remain to be elucidated. The present studies were designed to investigate the contractile effects of hydrogen peroxide (H2O2), one of the reactive oxygen species, on isolated ring segments of rat aorta with and without endothelium. H2O2 induced an endothelium-independent contraction in isolated rat aorta ring segments in a concentration-dependent manner at concentrations from 5 x 10(-6) to 5 x 10(-3) M. H2O2-induced contractions of denuded rat aorta rings were stronger than those on intact rat aorta segments. The contractile effects of H2O2 were inhibited completely by 1200 u/ml catalase. The presence of 1.0 microM Fe2+ or 10 microM proadifen, a cytochrome P450 monooxygenase inhibitor, potentiated the contractile effect of H2O2 on isolated rat aorta segments. 1 mM deferoxamine (a Fe2+ chelator) or 100 microM dimethyl sulfoxide (a hydroxyl radical scavenger) significantly attenuated the vessel contractions induced by hydrogen peroxide plus Fe2+ or hydrogen peroxide itself. Removal of extracellular Ca2+ ([Ca2+]0), addition of 5 microM verapamil, administration of a protein kinase C inhibitor (staurosporine), treatment with an inhibitor of protein tyrosine phosphorylation (genistein) or employment of 5.0 microM indomethacin resulted in a significant attenuation of the contractile responses of the vessels to H2O2. Pharmacological antagonists (e.g. a muscarinic acetylcholine receptor antagonist (atropine), an antagonist of histamine H1 receptors (diphenhydramine), an antagonist of histamine H2 receptors (cimetidine), an alpha-adrenoceptor antagonist (phentolamine), a beta-adrenoceptor antagonist (propranolol) and an antagonist of serotonin receptor (methysergide)) did not inhibit or attenuate the contractions induced by H2O2. Exposure of primary aortic smooth muscle cells to H2O2 (5 x 10(-6) to 5 x 10(-3) M) produced significant rises of intracellular Ca2+ ([Ca2+]i) within 20 s. Employment of 1.0 microM Fe2+ markedly enhanced the increment in [Ca2+]i in the smooth muscle cells. 10 microM proadifen treatment failed to alter the hydrogen peroxide-induced increment in [Ca2+]i of the smooth muscle cells. However, the presence of 5 microM indomethacin significantly attenuated the rise in [Ca2+]i in smooth muscle cells. The present results suggest that H2O2 can induce contractions of rat aorta segments, at pathophysiological concentrations, which are Ca2+-dependent. Hydroxyl radicals (.OH), cyclooxygenase products, protein kinase C and products of protein tyrosine phosphorylation appear to play some role in hydrogen peroxide-induced contractions. Metabolites catalyzed by cytochrome P450-dependent enzymes (upon treatment with hydrogen peroxide) appear to exert a vasodilator effect on rat aorta segments. Lastly, some unidentified mediators, produced by a cytochrome P450 inhibitor (proadifen), during hydrogen peroxide treatment, appear to play some role in contraction of vascular smooth muscle of rat aorta segments in vitro.
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Yang ZW, Yang FY. Sensitivity of Ca2+ transport of mitochondria to reactive oxygen species. Biosci Rep 1997; 17:557-67. [PMID: 9561301 DOI: 10.1023/a:1027316424985] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The relationship between Ca2+ transport and energy transduction of myocardial mitochondria in the presence of reactive oxygen species was investigated. Following treatment with oxygen free radicals [superoxide(O2.-) or hydroxyl radical (.OH)], lipid free radicals in myocardial mitochondrial membrane could be detected by using the method of EPR spin trap. Simultaneously there were obvious alterations in the free Ca2+ ([Ca2+]m) in the mitochondrial matrix; the physical state of membrane lipid; the efficiency of oxidative phosphorylation (ADP/O); the value of the respiratory control ratio (RCR); and the membrane potential of the inner membrane of myocardial mitochondria. If the concentrations of reactive oxygen species were reduced by about 30%, the alterations in the physical state of the membrane lipid and energy transduction of myocardial mitochondria were not observed, but the changes in Ca2+ homeostasis remained. We conclude that Ca2+ transport by myocardial mitochondria is more sensitive to agents such as O2.- or OH, etc. than are oxidation phosphorylation and the respiratory chain.
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Nimgaonkar VL, Yang ZW, Zhang XR, Brar JS, Chakravarti A, Ganguli R. Association study of schizophrenia and the IL-2 receptor beta chain gene. AMERICAN JOURNAL OF MEDICAL GENETICS 1995; 60:448-51. [PMID: 8546160 DOI: 10.1002/ajmg.1320600517] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A case-control association study was conducted in Caucasian patients with schizophrenia (DSM-III-R, n = 42) and unaffected controls (n = 47) matched for ethnicity and area of residence. Serum interleukin-2 receptor (IL-2R) concentrations, as well as a dinucleotide repeat polymorphism in the IL-2R beta chain gene, were examined in both groups. No significant differences in IL-2R concentrations or in the distribution of the polymorphism were noted. This study does not support an association between schizophrenia and the IL-2R beta gene locus, contrary to the suggestive evidence from linkage analysis in multicase families.
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Chengappa KN, Nimgaonkar VL, Bachert C, Yang ZW, Rabin BS, Ganguli R. Obstetric complications and autoantibodies in schizophrenia. Acta Psychiatr Scand 1995; 92:270-3. [PMID: 8848952 DOI: 10.1111/j.1600-0447.1995.tb09582.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Our hypothesis stated that patients with schizophrenia who had obstetric complications (OC) were more likely to have autoimmune abnormalities than those without OC. OC were rated using a checklist. Anti-brain autoantibodies were measured in serum using an enzyme immunoassay. Autoantibodies to non-CNS tissues were detected using serological procedures. There were no significant differences between the groups with respect to anti-brain antibodies, but patients with OC (n = 24) had a significantly higher prevalence of autoantibodies to non-CNS tissues than patients without OC (n = 25). Both groups were receiving neuroleptic drugs. OC may contribute to autoimmune abnormalities among patients with schizophrenia.
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Lin JQ, Xu ZS, Zhang HY, Yang ZW, Xu YH. [An EGFR antisense oligodeoxynucleotides and its phosphorothioate analogue inhibit the growth of human hepatocarcinoma BEL-7404 cells]. SHI YAN SHENG WU XUE BAO 1995; 28:241-6. [PMID: 8571707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have previously reported that the malignant phenotype of human liver carcinoma cell line BEL-7404 was reversed by antisense EGFR RNA. The aim of this paper is to explore the effects of an oligomer targeted to mRNA for EGFR and growth of BEL-7404 cells. A 21-mer oligodeoxynucleotides (ODNs) complementary to the 5' initiation region of mRNA for EGFR was synthesized and added to medium. The results showed that the growth of BEL-7404 cells was inhibited by ODNs at concentration of 3.2 mumol/L. Inhibition of DNA synthesis of BEL-7404 cells was dose-dependent and reached to 62.1% at 3.2 mumol/L as measured by 3H-thymidine incorporation test. The inhibition of EGFR gene transcription of the cells was up to 10.5% and 14.3% respectively after incubation with ODNs by 5 and 24 hours as measured by densitometric scanning of dot (RNA) blots of EGFR. The EGFR protein (P 170) expression was also found to be blocked by 4 days' antisense oligomer treatment up to 37.4% as measured by densitometric scanning of specific band of Western blot. The oligonucleotide phosphorothioate (S-ODNs) complementary to the same region of the gene was also synthesized and its growth inhibition effects on BEL-7404 cells were compared with those of unmodified oligomers. ODNs attained their highest effect within 30 hours. The proliferation inhibition rate of the cells didn't increase when cells were cultured in serum free medium. In contrast, the S-ODNs induced inhibition reached comparable level after 96 hours treatment as measured by 3H-thymidine uptake and the effect lasted longer, 1 mumol/L S-ODNs showed a little effect on BEL-7404 cells' proliferation. We concluded that the antisense oligomers directed to mRNA for EG-FR could inhibit the BEL-7404 cells growth by blocking the EGFR gene expression in some degree and the phosphorothioate analogues were more stable than the unmodified ODNs in vitro.
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Ganguli R, Brar JS, Chengappa KR, DeLeo M, Yang ZW, Shurin G, Rabin BS. Mitogen-stimulated interleukin-2 production in never-medicated, first-episode schizophrenic patients. The influence of age at onset and negative symptoms. ARCHIVES OF GENERAL PSYCHIATRY 1995; 52:668-72. [PMID: 7632120 DOI: 10.1001/archpsyc.1995.03950200058014] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Decreased interleukin-2 (IL-2) production is characteristic of active autoimmune diseases and has previously been reported in patients with schizophrenia. We attempted to replicate this finding in never-medicated schizophrenic patients and examine the possible correlation between IL-2 production and clinical variables. METHODS The production of IL-2 was measured in equal numbers (N = 33) of DSM-III-R-diagnosed schizophrenic patients and controls who were matched for age, race, and gender. Patients were also assessed for positive, negative, and depressive symptoms. RESULTS The production of IL-2 was significantly lower in patients than in controls. There was a significant positive correlation between IL-2 production and age at onset, and significant negative correlation between IL-2 production and negative symptom scores. In multivariate analyses, the predictive power was stronger for age at onset than for negative symptoms. Positive or depressive symptoms were unrelated to IL-2 production. CONCLUSIONS Our finding of low IL-2 production in neuroleptic-native schizophrenic patients confirms that this finding is not confounded by medications. The correlation of low IL-2 production with younger age at onset suggests that this may be a marker for a subtype of the illness or for severity.
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Chengappa KN, Ganguli R, Yang ZW, Shurin G, Brar JS, Rabin BS. Impaired mitogen (PHA) responsiveness and increased autoantibodies in Caucasian schizophrenic patients with the HLA B8/DR3 phenotype. Biol Psychiatry 1995; 37:546-9. [PMID: 7619978 DOI: 10.1016/0006-3223(94)00363-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Chengappa KN, Ganguli R, Yang ZW, Schurin G, Brar JS, Rosenbleet JA, Rabin BS. Differences in serum interleukin-6 (IL-6) between healthy dextral and non-dextral subjects. Neurosci Res 1994; 20:185-8. [PMID: 7808701 DOI: 10.1016/0168-0102(94)90036-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Serum interleukin-6 (IL-6) was measured in picograms/ml pg/ml using an immunoassay (ELISA) in healthy individuals (n = 148), of whom 128 were classified as dextral and 20 as non-dextral, as per a laterality questionnaire. Only 3 (15%) non-dextral individuals had serum IL-6 levels above the lower limit of the assay sensitivity as compared to 59 (46%) of dextral individuals (P < 0.013). There were no significant correlations between previously determined mitogen stimulated interleukin-2 production and autoantibodies in a subset of the same individuals. While this data does not provide casual information, it adds to the evidence of the asymmetric regulation of immune functions by the cerebral hemispheres.
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Silver MA, Yang ZW, Ganguli R, Nimgaonkar VL. An inhibitory effect of psychoactive drugs on a human neuroblastoma cell line. Biol Psychiatry 1994; 35:824-6. [PMID: 7913837 DOI: 10.1016/0006-3223(94)91145-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Yang ZW, Chengappa KN, Shurin G, Brar JS, Rabin BS, Gubbi AV, Ganguli R. An association between anti-hippocampal antibody concentration and lymphocyte production of IL-2 in patients with schizophrenia. Psychol Med 1994; 24:449-455. [PMID: 8084939 DOI: 10.1017/s0033291700027410] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Serum concentrations of anti-hippocampal antibodies and in vitro production of the lymphokine interleukin-2 (IL-2) in response to phytohaemagglutinin (PHA) stimulation were determined using an enzyme immunoassay in 49 schizophrenic patients and 41 healthy controls. Decrease in IL-2 production, a finding frequently associated with many autoimmune diseases, was associated with an elevation in anti-hippocampal antibody optical density (AHA-OD) in schizophrenic patients. Although some control subjects had elevated antibody levels, this elevation was not associated with decreased IL-2 production. Low IL-2 production is well known to be a state marker associated with active autoimmune disease. We suggest that production of hippocampal antibody is a trait marker of vulnerability to autoimmune diseases. Thus, our finding of low IL-2 production in patients with high concentrations of hippocampal antibody is compatible with the possibility that such patients have an ongoing autoimmune process.
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Yang ZW, Gao YG, Zhang H. [Clinical observation on 80 cases with duodenal bulbar ulcer treated with kuiyangqing pill]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1994; 14:152-3, 133. [PMID: 7950184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
UNLABELLED 80 patients with duodenal bulbar ulcer were divided into two groups: one was the group of ulcer with Excess-Heat Syndrome (EHS); the other was that with Deficiency-Cold Syndrome (DCS). Both groups of patients were treated with Kuiyangqing Pill (KYQP) for observation, 32 cases treated with bismuth aluminate tablets as control. RESULTS The therapeutical effect of EHS was better than that of the control. The recovery rate was 91.5%. The effective rate was 97.9% (P < 0.05). While the curative effect of DCS group was not so good as that of the control.
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Ganguli R, Brar JS, Chengappa KN, Yang ZW, Nimgaonkar VL, Rabin BS. Autoimmunity in schizophrenia: a review of recent findings. Ann Med 1993; 25:489-96. [PMID: 8251150 DOI: 10.3109/07853899309147317] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The pathophysiology of psychotic and other symptoms in schizophrenia remains a mystery despite decades of research. Even though it has been suspected for many years that autoimmune mechanisms may play a role in the pathophysiology of schizophrenia, firm evidence for this hypothesis has been lacking. Our studies, over the last 10 years, have revealed that a subgroup of schizophrenics have several significant immunological abnormalities, including increased prevalence of autoimmune diseases and of antinuclear antibodies (ANA) and anticytoplasmic antibodies (ACA), decreased lymphocyte interleukin-2 (IL-2) production, increased serum IL-2 receptor concentration, increased serum IL-6 concentration, and an association with HLA antigens. These findings are characteristic of autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis and insulin-dependent diabetes mellitus. We also found that some schizophrenics have antibodies to hippocampal antigens (AHA) in their serum, together with lowered IL-2 production. None of the above findings can be interpreted as definitely confirming the role of autoimmunity in schizophrenia. Nevertheless, taken together, the recent evidence points towards the existence of a subgroup of schizophrenics who have immunological findings consistent with that hypothesis. Further studies directed at finding the brain antigens targeted by the immune system in these patients, and longitudinal studies correlating clinical and immune changes over time, are needed.
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Chengappa KN, Ganguli R, Ulrich R, Rabin BS, Cochran J, Brar JS, Yang ZW, Deleo M. The prevalence of autoantibodies among right and left handed schizophrenic patients and control subjects. Biol Psychiatry 1992; 32:803-11. [PMID: 1450294 DOI: 10.1016/0006-3223(92)90083-c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sera from schizophrenic patients (n = 186) and healthy control subjects (n = 346) were tested for the presence of seven common autoantibodies by standard immunological methods. The association between handedness and autoantibodies was tested in a multi-way contingency table using a log-linear model. For men, but not women, nondextrals (patients and controls) were twice as likely to test positive for autoantibodies than dextrals (p = 0.0002). Although more women (33%) than men (24%) tested positive for autoantibodies, handedness was not a distinguishing factor among women. These data suggest that sinistrality and gender are associated with autoantibodies in a subgroup of schizophrenic patients and healthy control subjects.
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Chengappa KN, Ganguli R, Yang ZW, Brar JS, Li L, Rabin BS. Left-handed first-episode, neuroleptic-naive schizophrenic patients have a higher prevalence of autoantibodies. Schizophr Res 1992; 8:75-80. [PMID: 1419935 DOI: 10.1016/0920-9964(92)90063-b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Using standard immunological techniques, sera from first-episode, neuroleptic-naive schizophrenic patients (n = 51) and age, race and sex matched healthy controls (n = 51) were screened for seven common autoantibodies. Significantly more left-handed (67%) than right-handed (23%) schizophrenic patients had autoantibodies (p = 0.011). Left-handed schizophrenic patients were six times more likely than right-handed patients or controls and four times more likely than left-handed controls to test positive for autoantibodies (p = 0.012). These data suggest that disease and sinistrality contribute to the excess of autoantibodies in schizophrenia.
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73
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Chengappa KN, Carpenter AB, Yang ZW, Brar JS, Rabin BS, Ganguli R. Elevated IgG anti-histone antibodies in a subgroup of medicated schizophrenic patients. Schizophr Res 1992; 7:49-54. [PMID: 1350460 DOI: 10.1016/0920-9964(92)90073-e] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
A total of 57 schizophrenic patients (of which 17 were first-episode, neuroleptic naive) and 76 healthy controls were screened for anti-histone IgG antibodies using an enzyme immunoassay (ELISA). All patients had significantly higher anti-histone antibody titers than controls (t = 3.1, p less than 0.003). Previously medicated patients had significantly higher titers than neuroleptic-naive first episode patients (t = 2.87, p less than 0.006). This study suggests that neuroleptic medications are associated with anti-histone antibodies.
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74
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Chengappa KN, Ganguli R, Yang ZW, Schurin G, Cochran J, Brar JS, Rabin B. Non-right sidedness: an association with lower IL-2 production. Life Sci 1992; 51:1843-9. [PMID: 1447950 DOI: 10.1016/0024-3205(92)90035-n] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Using a laterality questionnaire, 138 normal healthy individuals were classified as right-sided and 25 as non-right sided. Interleukin-2 (IL-2) was generated from whole blood obtained from these subjects using mitogen (PHA) stimulation. IL-2 was quantitated in picograms/ml using an enzyme immunoassay (ELISA). Additionally, sera from these subjects were tested for 7 autoantibodies by standard serological methods. As compared to right sided subjects, non-right sided individuals had significantly lower IL-2 production. Non-right sided individuals with autoantibodies had significantly lower IL-2 production than right sided subjects with or without autoantibodies, but did not differ significantly from their non-right sided counterparts without autoantibodies. These data support the increasing evidence for the differential and lateralized regulation of immune functions by the right and left cerebral regions.
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75
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Chengappa KN, Carpenter AB, Keshavan MS, Yang ZW, Kelly RH, Rabin BS, Ganguli R. Elevated IGG and IGM anticardiolipin antibodies in a subgroup of medicated and unmedicated schizophrenic patients. Biol Psychiatry 1991; 30:731-5. [PMID: 1683585 DOI: 10.1016/0006-3223(91)90019-i] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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76
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Yang ZW, Wreford NG, de Kretser DM. A quantitative study of spermatogenesis in the developing rat testis. Biol Reprod 1990; 43:629-35. [PMID: 2289015 DOI: 10.1095/biolreprod43.4.629] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Quantitative (stereological) studies were performed to determine the number of germ cells in the developing rat testis. Sprague-Dawley rats aged 1-70 days were fixed by immersion or perfusion and embedded in Epon Araldite. Blocks of tissue were sectioned at 1.5 microns and stained with toluidine blue dye. Sections were systematically scanned and the areal density of nuclear profiles counted using an unbiased counting frame. Numerical density and absolute number of germ cells in the processed block were then estimated. Corrections for processing shrinkage were determined by comparing the volume of processed and unprocessed samples. The results demonstrate the necessity of determining absolute number rather than volume density (or areal density) in comparing germ cell numbers. In these experiments, spermatogonial numbers stabilized in the range 18.4-23.6 million per testis on Day 30. The number of primary spermatocytes that were first apparent on Day 15 increased rapidly to 54.6 million per testis on Day 30 and then slowly to 73.6 million on Day 70. Round spermatids were first apparent on Day 25 and increased rapidly to 85.7 million per testis on Day 40, then continued to increase to 151.9 million on Day 70. The study provides both methods and baseline data for future experiments involving manipulation of the spermatogenic potential of the testis.
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77
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Chen M, Yang ZW, Zhu JT, Xiao ZY, Xiao R. [Anti-arrhythmic effects and electrophysiological properties of Ophiopogon total saponins]. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1990; 11:161-5. [PMID: 2275393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The arrhythmias induced by chloroform-epinephine, BaCl2, and aconitine were prevented and antagonized by Ophiopogon total saponins (OTS) which were extracted from the root of Ophiopogon japonicus (Thunb) Ker-Gawl. The incidence of ventricular arrhythmia produced by ligation of the left anterior descending coronary artery was effectively decreased without any changes in the hemodynamic indices of dogs. The electrophysiological effects of OTS in vivo and in vitro were studied by means of contact electrode and intracellular microelectrode techniques. The results showed that OTS shortened APD10, APD50, APD90; decreased APA and Vmax of both monophasic and transmembrane action potentials. OTS also increased the ERP/APD ratio and prevented or abolished the arrhythmikinesis provoked by ouabain and aconitine. The anti-arrhythmic properties of OTS lead us to draw an inference that the anti-arrhythmic mechanism may be related to the blocking of sodium and calcium channels.
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78
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Paleos GA, Yang ZW, Byrd JC. Ontogeny of PCP and sigma receptors in rat brain. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1990; 51:147-52. [PMID: 2157561 DOI: 10.1016/0165-3806(90)90270-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Phencyclidine (PCP) binds with high affinity to two receptors in rat brain--the PCP receptor and the Sigma receptor. Although both receptors are present prenatally, and their number increases postnatally, their rate of increase, compared to the increase in brain protein, is quite different, yielding distinct ontogenic profiles. Thus, PCP receptors are present on prenatal day 2 and show a further 15-fold increase by postnatal day 28. In contrast, Sigma receptors are present at their highest density during the perinatal period, and decline thereafter. The Kd of the PCP receptor for TCP remains constant throughout development, whereas the Kd of the Sigma receptor for (+)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine decreases 40% postnatally. On postnatal day 6, both PCP and Sigma receptors display a pharmacological profile similar to that observed in adult animals.
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Yang ZW, Paleos GA, Byrd JC. Expression of (+)-3-PPP binding sites in the PC12 pheochromocytoma cell line. Eur J Pharmacol 1989; 164:607-10. [PMID: 2569979 DOI: 10.1016/0014-2999(89)90274-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Phencyclidine binds with high affinity to both PCP and sigma receptors. We investigated whether the clonal cell line PC12 expressed either of these receptors, and found that these cells contain a haloperidol-sensitive (+)-[3H]3-PPP binding site with a KD of 56 nM, but no PCP binding sites. The (+)3-PPP binding sites in PC12 cells displayed a reversed stereoselectivity for the benzomorphan opiates compared to CNS sigma receptors. Neither nerve growth factor nor sodium butyrate treatment affected the expression of either (+)-3-PPP or TCP binding sites in PC12 cells.
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80
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Hei YJ, Yang ZW, Zhang ZY, Wang YX, Liu JY, Yang ZM, Miao XC. [Effects of China-made amrinone on isolated sino-atrial and papillary muscle, hemodynamics and cardiac performance in dogs]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1988; 19:380-4. [PMID: 3243533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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81
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Yang ZW, Babitch JA. Factors modulating filament formation by bovine glial fibrillary acidic protein, the intermediate filament component of astroglial cells. Biochemistry 1988; 27:7038-45. [PMID: 3196699 DOI: 10.1021/bi00418a055] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Glial fibrillary acidic protein (GFAP) is soluble in low ionic strength solutions but shows a strong tendency toward assembly with increasing ionic strength as revealed by electron microscopy and turbidity measurements. Increasing K+, Na+, and Li+ concentrations cause an increase followed by a decrease in GFAP turbidity with a maximum at 200 mM, but their effects are much weaker than effects of divalent cations at the same ionic strength. Ca2+, Mg2+, Mn2+, and Ba2+ promote assembly at millimolar concentrations, and 10 microM Cu2+ causes rapid aggregation. The critical concentration for GFAP assembly was 0.08 +/- 0.04 mg/mL in 2 mM Tris-HCl, 60 mM KCl, and 1 mM CaCl2, pH 6.8. The Mr 38,000 rod domain of GFAP obtained by limited chymotryptic digestion is more soluble in 100 mM imidazole hydrochloride buffer, pH 6.8, than the intact molecule, and removal of the end pieces greatly reduces the ability of GFAP to form filaments. BNPS-skatole (2-[(2-nitrophenyl)sulfenyl]-3-methyl-3-bromoindolenine) treatment releases a Mr 30,000 N-terminus and a Mr 20,000 C-terminus. The Mr 30,000 polypeptide shows a higher affinity than the Mr 20,000 fragment for intact GFAP. Arginine and lysine at low concentrations slightly accelerate GFAP assembly, but above 100 mM both amino acids inhibit assembly. ATP, GTP, CTP, and UTP do not show significant effects on GFAP assembly. Dephosphorylation by alkaline phosphatase slightly reduces the assembly ability of GFAP, but phosphatase-treated GFAP still is assembly competent.
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82
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Yang ZW, Kong CF, Babitch JA. Characterization and location of divalent cation binding sites in bovine glial fibrillary acidic protein. Biochemistry 1988; 27:7045-50. [PMID: 3196700 DOI: 10.1021/bi00418a056] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In our previous work [Yang, Z. W., & Babitch, J. A. (1988) Biochemistry (preceding paper in this issue)] divalent cations were found to be more effective promoters of astroglial filament formation than were monovalent cations. To determine if one or more divalent cation binding sites were the basis for this difference, glial fibrillary acidic protein (GFAP) was attached to nitrocellulose membranes and bathed in 1 microM 45CaCl2 in 60 mM KCl, 0.5 mM MgCl2, and 10 mM imidazole hydrochloride, pH 7.4. After removal of unbound 45Ca2+, GFAP was observed to bind calcium. Flow dialysis experiments showed that GFAP, dissolved in 2 mM Tris-HCl, pH 7.5, contained three classes of binding sites and 0.61 +/- 0.08 (SD), 1.7 +/- 0.4, and 4.6 +/- 0.2 sites per GFAP molecule with dissociation constants of 0.66 +/- 0.01 microM, 6.6 +/- 0.3 microM, and 44 +/- 1 microM, respectively. After addition of 0.5 mM MgSO4 to the flow dialysis solution, the high- and low-affinity sites were not observed while the remaining sites (1.95 +/- 0.15 per GFAP molecule) had a Kd = 2.16 +/- 0.25 microM. This showed that the high- and low-affinity sites are "Ca2+-Mg2+" sites while sites with intermediate affinity are calcium specific. To locate the calcium-binding regions, GFAP peptides were examined for calcium binding by calcium-45 autoradiography. The calcium-specific binding areas were localized in coil I. Computer-assisted analysis of the GFAP sequence revealed several EF-hand-like areas which could be the calcium binding sites. We conclude that divalent cations may play both structural and regulatory roles in astroglial intermediate filaments.
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Sun CJ, Yang ZW. [Study of factors influencing the Saltzman factor in spectrophotometric determination of NO2 in air]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1988; 19:170-3. [PMID: 3198099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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84
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Hei YJ, Yang ZW, Zhang ZY. [In vitro study of cardiotonic and vasodilator actions of Chinese-made amrinone]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1987; 18:252-5. [PMID: 3679177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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85
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Wang Y, Liu XY, Yang ZW, Wang QW, Xu YZ, Wang QZ, Xu JF. The reaction mechanism of N-benzoylimidazole with ribonucleotides. Nucleic Acids Res 1987; 15:4291-305. [PMID: 3588294 PMCID: PMC340848 DOI: 10.1093/nar/15.10.4291] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The reaction of uridine 3'-phosphate with benzoylimidazole in the absence and presence of a strong base was followed up by 31P and 1H nmr as well as paper electrophoresis. Possible reaction courses were proposed, the reaction rate constants were calculated and the reaction mechanism was discussed. It is possible to selectively acylate ribonucleotides with benzoylimidazole by appropriate choice of the base used.
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86
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Yang ZW, Babitch JA. Detection and characterization of some new basic proteins in chicken postsynaptic densities. J Neurochem 1986; 47:282-90. [PMID: 3711904 DOI: 10.1111/j.1471-4159.1986.tb02860.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Chicken brain postsynaptic density (PSD) polypeptides, obtained by treating synaptosomes with 0.5% Triton X-100 and then further purified on a sucrose gradient, are demonstrated to contain four basic proteins of 76K (pI greater than 9.2), 58K (pI 8.1-8.8, heterogeneous), 40K (pI 9.0), and 24K (pI 8.9). Nonequilibrium pH gradient-sodium dodecyl sulfate two-dimensional gels further reveal six more basic proteins with pI values higher than 9.2: 76K, 52K, 47K, 45K, 36K, and 34K. These basic proteins are a major part of the total chicken PSD polypeptides appearing on the gels. Some of these basic proteins (58K, 52K, 47K, 36K, 24K, and two at 76K) are distinguishable from those of brain mitochondria, the major contaminant. The 40K and 34K proteins may be common mitochondrial polypeptides. The 45K protein is probably a mitochondrial contaminant. A number of proteins including 76K (synapsin I-like protein) and 58K, along with some other minor ones, can be phosphorylated by endogenous protein kinase(s) in the presence of Ca2+, Mg2+, and [gamma-32P]ATP. No PSD basic proteins bind Ca2+.
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87
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Wang Y, Yang ZW, Wang QW, Xu YZ, Liu XY, Xu JF, Chen CH. The role of metaphosphate in the activation of the nucleotide by TPS and DCC in the oligonucleotide synthesis. Nucleic Acids Res 1986; 14:2699-706. [PMID: 3754328 PMCID: PMC339692 DOI: 10.1093/nar/14.6.2699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The course of the activation of 3'-acetylthymidine 5'-phosphate by TPS and DCC were followed up by 31P FT nmr. The fact that the "metaphosphate" (delta-5.1) first becomes detectable only at later stage of the activation and does coexist with pyrophosphate and triphosphate suggests that the pyridinium derivative of "metaphosphate" is most probably not directly formed from the hypothetical mixed anhydride or active "pseudourea" right at the beginning of the reaction of pdTac with TPS or DCC, but rather formed at later stage of the activation reaction from the degradation of the pyro- and triphosphates by the activating agent. The mixed anhydride or the active "pseudourea" is most possibly the active key intermediate.
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88
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Wang DB, Zheng KQ, Qiu MS, Liang ZH, Wu RL, Chen CQ, Wang EB, Zhu YS, Shen QX, Yu YH, Wang Y, Chen HB, Yang ZW, Lu YH, Chen S, Wang GH, Hu MH. Total synthesis of yeast alanine transfer ribonucleic acid. SCIENTIA SINICA. SERIES B, CHEMICAL, BIOLOGICAL, AGRICULTURAL, MEDICAL & EARTH SCIENCES 1983; 26:464-81. [PMID: 6553356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
By a combination of chemical and enzymatic methods, small oligonucleotides with lengths varying from 2 to 8 nucleotides were synthesized from mononucleotides. The small oligonucleotides were then ligated with T4 RNA ligase into six large oligonucleotides (9 to 19 nucleotides long) which were further ligated to form two half molecules with 35 and 41 nucleotides respectively. Finally, the two synthetic half molecules were annealed and ligated to obtain the whole molecule of yeast alanine tRNA (tRNAAlay). Prior to this, two semi-syntheses were performed, i.e. ligation of the synthetic 5'-half molecule with the natural 3'-half molecule and that of the natural 5'-half molecule with the synthetic 3'-half molecule. Both the semi-synthetic tRNAAlay and the synthetic tRNAAlay occupy the same position as the natural tRNAAlay after electrophoresis on a 20% polyacrylamide gel. They have the same chemical composition (containing 9 modified nucleotides of 7 different species) and structure as the natural tRNAAlay and are biologically active, i.e. accepting and transferring alanine into proteins in a cell-free protein synthesizing system, the accepting activity of the synthetic product is 52-66% of that of the natural tRNAAlay and 91-106% of that of the reconstituted product of the two natural half molecules. The incorporation activity of alanine into proteins of the synthetic 3H-alanine tRNAAlay is 63%, corresponding to 91% of that of the natural tRNAAlay and 115% of that of the reconstituted product of the two natural half molecules. To the best of our knowledge, this is the first time that a natural RNA with biological activity is synthesized.
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