626
|
Chan SH, Kuo JS, Chen YH, Hwa JY. Modulatory actions of the gigantocellular reticular nucleus on baroreceptor reflexes in the cat. Brain Res 1980; 196:1-9. [PMID: 6772273 DOI: 10.1016/0006-8993(80)90712-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
627
|
Yang SD, Chen YH. [The determination of curcumol in the volatile oil of Curcuma aromatica by phloroglucinol spectrophotometry (author's transl)]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1980; 15:228-233. [PMID: 7457140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
|
628
|
Chen YH, Hancock RE, Mishell RI. Mitogenic effects of purified outer membrane proteins from Pseudomonas aeruginosa. Infect Immun 1980; 28:178-84. [PMID: 6769818 PMCID: PMC550909 DOI: 10.1128/iai.28.1.178-184.1980] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Three major outer membrane proteins from Pseudomonas aeruginosa PAO1 were purified and tested for their ability to stimulate resting murine lymphocytes to proliferate. It was demonstrated that picomole amounts of all three proteins were mitogenic for both intact and T-lymphocyte-depleted populations of spleen cells from C3H/HeJ mice. In contrast, they had no activity against either mature or immature thymocytes. Since the strain of mice used is unable to respond to lipopolysaccharide, we condlude that the three proteins are B-cell mitogens.
Collapse
|
629
|
Chen YH. [Clinical observations on the effects of Bufo secretion preparation for painless pulpectomy (author's transl)]. ZHONGHUA KOU QIANG KE ZA ZHI [CHINESE JOURNAL OF STOMATOLOGY] 1980; 15:51-2. [PMID: 6950891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
630
|
Mishell RI, Bradley LM, Chen YH, Grabstein KH, Shiigi SM. Glucocorticosteroid response-modifying factors derived from accessory cells. Ann N Y Acad Sci 1979; 332:433-45. [PMID: 316982 DOI: 10.1111/j.1749-6632.1979.tb47137.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
631
|
Chen YH, MacGregor JP, Goldstein DA, Hall MR. Histone modifications in simian virus 40 and in nucleoprotein complexes containing supercoiled viral DNA. J Virol 1979; 30:218-24. [PMID: 225517 PMCID: PMC353315 DOI: 10.1128/jvi.30.1.218-224.1979] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Simian virus (SV40) nucleoprotein complexes containing circular supercoiled viral DNA were extracted from infected cells and purified by differential centrifugation. The protein content of these complexes was compared by electrophoresis on 15% acrylamide gels with the protein content of purified SV40 virions and with histones from virus-infected cells. The electrophoretic patterns of histones from each of the sources revealed several major differences. SV40 virions contained histones H3, H2B, H2A, and H4 but not H1. Nucleoprotein complexes and host cells contained all five major histone groups. Relative to cellular histones, virion and nucleoprotein complex histones were enriched 15 to 40% in histones H3 and H4. In addition to the major classes of histones, several subfractions of histones H1, H3, and H4 were observed in acrylamide gels of proteins from SV40 virions and viral nucleoprotein complexes. Acetate labeling experiments indicated that each subfraction of histones H3 and H4 had a different level of acetylation. The histones from SV40 virions and nucleoprotein complexes were acetylated to significantly higher levels than those of infected host cells. No apparent differences in phosphorylation of the major histone groups were observed.
Collapse
|
632
|
Teng SW, Huang YK, Chang SI, Chen YH, Huang YJ. [Improving children's understanding of body organs: an evaluation of teaching material design]. HU LI ZA ZHI THE JOURNAL OF NURSING 1978; 25:89-98. [PMID: 255582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
633
|
Chen YH, Heller P. Lymphocyte surface immunoglobulin density and immunoglobulin secretion in vitro in chronic lymphocytic leukemia (CLL). Blood 1978; 52:601-8. [PMID: 678675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Lymphocyte surface immunoglobulin (SIg) and immunoglobulin (Ig) secretion were studied in 14 patients with chronic lymphocytic leukemia (CLL) and 12 healthy subjects. The determination of SIgM-bearing (SIgM+) cells by immunofluorescent staining and the quantification of SIgM by radioimmunoassay (RIA) permitted the calculation of the SIgM density. In 12 normal subjects the percentage of SIgM+ cells averaged 8% (range 4%-12%) and the SIgM density 10.2 ng antigenic equivalent/10(6) SIgM+ cells (SD 4.3). In 12 patients with CLL the respective figures were 68% (range 35%-90%) and 0.68 ng (SD 0.57). Ig secretion from pokeweed mitogen-stimulated CLL cells was markedly diminished as compared with normal lymphocytes. In coculture experiments CLL cells had no suppressive effect on Ig secretion of normal lymphocytes and normal lymphocytes did not enhance Ig secretion leukemic lymphocytes. These results indicate that the impaired secretory activity of CLL cells results from an intrinsic anomaly of these cells.
Collapse
|
634
|
Hung MC, Pan YH, Cheng KL, Chen YH. The status of tyrosyl residues in a Formosan cobra cardiotoxin. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 535:178-87. [PMID: 28149 DOI: 10.1016/0005-2795(78)90083-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Spectrophotometric titration of Formosan cobra cardiotoxin showed that two of the three tyrosyl residues were titrated freely with a normal apparent pKa of 9.6 whereas the remaining one ionized at pH above 11.0. Nitration of cardiotoxin in Tris . HCl buffer with tetranitromethane resulted in the selective nitration of tyrosine 11 and tyrosine 22. It also revealed that tyrosine 51 was the abnormal one in the spectrophotometric titration. Complete nitration occurred in the presence of 6.0 M guanidine hydrochloride. Compared with the conformation of native cardiotoxin, the peptide conformation of the partially nitrated cardiotoxin did not change significantly but the conformation of the completely nitrated cardiotoxin changed remarkably. The biological activity of cardiotoxin was indeed affected by nitration, but the immunological activity was nearly intact even when all the tyrosine residues were nitrated.
Collapse
|
635
|
MacGregor JP, Chen YH, Goldstein DA, Hall MR. Properties of the histones associated with simian virus 40 replicative form nucleoprotein complex. Biochem Biophys Res Commun 1978; 83:814-21. [PMID: 213072 DOI: 10.1016/0006-291x(78)91467-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
636
|
Wong CH, Chen YH, Hung MC, Wang KT, Ho CL, Lo TB. Renaturation of a reduced Taiwan cobra cardiotoxin. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 533:105-11. [PMID: 76481 DOI: 10.1016/0005-2795(78)90553-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Refolding of a denatured protein obtained by reducing cardiotoxin from the Taiwan cobra with mercaptoethanol has been carried out in aqueous and non-aqueous solutions. Oxidation of the reduced protein in 0.05 M phosphate buffer (pH 7.2) resulted in isolating an active protein which showed, as compared to native cardiotoxin, identical conformation and biological activities such as lethality, antigenicity and muscle contracture inducing activity. On the other hand, the reduced protein was undergoing incorrect SS-pairing and several inactive products were formed in a mixture of 1,2-ethanediol and 1-propanol (1 : 1; v/v).
Collapse
|
637
|
Garcia JC, Chen YH, Hsu CS. Lymphocyte surface markers in acute lymphoblastic leukemia of adults. Am J Clin Pathol 1977; 68:543-6. [PMID: 303458 DOI: 10.1093/ajcp/68.5.543] [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: 12/14/2022] Open
Abstract
Leukemic cells from eight adult patients with acute lymphoblastic leukemia (ALL) were examined for the T-lymphocyte (T-cell) marker of sheep erythrocyte (E) receptors and for B-lymphocyte (B-cell) markers of surface immunoglobulins (SIg), complement receptors and FC receptors. Six of these patients' leukemic cells were devoid of both T- and B-cell markers, and therefore were "null" cells. The leukemic lymphoblasts of a 79-year-old patient had all B-cell markers, including monoclonal IgG K and receptors for complement and Fc. In cells from another patient (21 years old), only complement receptors were found. A review of the literature revealed that, similar to childhood ALL, adult cases of ALL were mostly of "null" cell type. All of the T-cell type was found in approximately 20% of patients. ALL of the B-cell type occurred only rarely. The latter cell type appeared to occur mainly in the middle-aged and the elderly.
Collapse
|
638
|
Hung MC, Chen YH. Conformational stability of a snake cardiotoxin. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1977; 10:277-85. [PMID: 591177 DOI: 10.1111/j.1399-3011.1977.tb02798.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A snake cardiotoxin from the venom of the Formosan cobra, Naja naja atra, is a basic polypeptide. The protein can be denatured in 6.0 M guanidine hydrochloride or at elevated temperatures. Its conformation remains virtually the same in solvents of lower polarity than water such as 1, 2-ethanediol or 1-propanol and 1, 2-ethanediol (1:1 v/v). The circular dichroism spectrum is atypical in water in that the peptide chromophores show a small negative CD band at 214 nm and a large positive one at 195 nm. To some extent the CD pattern resembles that of the beta-form but differs in specific positions and magnitudes. Considering that the theoretical CD of the reverse beta-bend and the characteristics of model polypeptides in beta-form manifest a similar pattern, we suggest that cobra cardiotoxin is rich in beta structure including beta pleated-sheets and beta reverse-turns.
Collapse
|
639
|
Abstract
Cobra neurotoxin from Formosan cobra (Naja naja atra) venom is a compact globular protein having an intrinsic viscosity of 4.5 mL/g. The protein is stable in 7.5 M urea but can be denatured in 4.1 M guanidine hydrochloride or at elevated temperature (above 70 degrees C). Its conformation remains virtually the same in solvents of lower polarity than water such as 1,2-ethanediol or a mixed solvent of 1-propanol-1,2-ethanediol-water (5:1:1 by volume). The circular dichroism spectrum is "atypical" in water in that the peptide chromophores show a small negative circular dichroic (CD) band at 215 nm, a large positive one at 199 nm, and another large negative one below 190 nm. The CD pattern resembles to some extent that of a beta form but differs in both positions and magnitudes from the latter. It agrees qualitatively with the theoretical calculations of the reverse beta bends, suggesting that cobra toxin contains a considerable amount of beta turns and possibly a mixture of beta form and beta turns.
Collapse
|
640
|
Chen YH, Reeve EB. Some factors influencing metabolism and distribution of fibrinogen in man and rabbits. Thromb Haemost 1977; 37:243-52. [PMID: 577627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
To shed some light on the homeostatic regulation of plasma fibrinogen, metabolic studies were made in healthy females, and in normal, thyroidectomized, and thyroxine-treated rabbits. In females, compared with normal males, plasma fibrinogen concentration, plasma and interstitial fibrinogen decreased consequent to an increased fractional catabolic rate and a normal fibrinogen synthesis rate. The interstitial/plasma fibrinogen ratio remained unchanged. In normal rabbits, with increasing body weight fractional catabolic rate and catabolic rate decreased, while fibrinogen concentration and plasma fibrinogen remained constant owing to a simultaneous decrease in fibrinogen synthesis. In addition, fractional transcapillary transfer rate and transcapillary flux also decreased resulting in a shrinkage of interstitial fibrinogen. Thyroidectomy and thyroxine-injection markedly altered fibrinogen metabolism: thyroid hormone accelerated fibrinogen catabolism but also stimulated synthesis. The net result was an increase in plasma fibrinogen and fibrinogen concentration. The interstitial/plasma fibrinogen ratio decreased in thyroxine-treated, and increased in thyroidectomized animals. This study defines the variations of the fibrinogen system parameters in these physiologic and pathologic conditions, and illustrates some patterns of alterations in fibrinogen metabolism.
Collapse
|
641
|
Chen YH, Lo TB, Lu HS. Conformation of snake toxins [proceedings]. Toxicon 1976; 14:410-1. [PMID: 1014022 DOI: 10.1016/0041-0101(76)90043-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
642
|
Lee TK, Yu H, Wang YH, Chen YH, Liaw H. Effect of cytochrome C on the cerebral blood flow and metabolism. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1975; 74:185-90. [PMID: 167100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
643
|
Chen YH, Yang JT, Chau KH. Determination of the helix and beta form of proteins in aqueous solution by circular dichroism. Biochemistry 1974; 13:3350-9. [PMID: 4366945 DOI: 10.1021/bi00713a027] [Citation(s) in RCA: 1685] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
644
|
Kao CL, Chen YH, Tang MC, Wen HK, Hsia S. Association of herpes simplex type 2 virus with cervical cancer of the uterus. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1974; 73:122-7. [PMID: 4368434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
645
|
Turnbull LB, Johnson CP, Chen YH, Sancilio LF, Bruce RB. Disposition and metabolism of 4-methyl-2(4-phenylbenzyl)-2-oxazoline-4-methanol in the rat and dog. J Med Chem 1974; 17:45-8. [PMID: 4808469 DOI: 10.1021/jm00247a010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
646
|
Fielden ML, Welstead WJ, Dawson ND, Chen YH, Mays RP, DaVanzo JP, Lunsford CD. Synthesis and central nervous system depressant activity of some 5-(2-substituted alkyl)-2-oxazolidinones. J Med Chem 1973; 16:1124-8. [PMID: 4795992 DOI: 10.1021/jm00268a012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
647
|
Chen YH, Yang JT, Martinez HM. Determination of the secondary structures of proteins by circular dichroism and optical rotatory dispersion. Biochemistry 1972; 11:4120-31. [PMID: 4343790 DOI: 10.1021/bi00772a015] [Citation(s) in RCA: 1632] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
648
|
Chen YH, Yang JT. A new approach to the calculation of secondary structures of globular proteins by optical rotatory dispersion and circular dichroism. Biochem Biophys Res Commun 1971; 44:1285-91. [PMID: 5168596 DOI: 10.1016/s0006-291x(71)80225-5] [Citation(s) in RCA: 273] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
649
|
Welstead WJ, Helsley GC, Lunsford CD, Chen YH, DaVanzo JP. Synthesis and biological activity of some 3-substituted amino-1-carbamoyl-and -thiocarbamolypyrrolidines. J Med Chem 1968; 11:1255-6. [PMID: 5680060 DOI: 10.1021/jm00312a606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|