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1.
Br J Pharmacol ; 107(2): 273-5, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1330170

RESUMEN

The non-peptide NK1 receptor antagonist, CP-96,345, and its 2R,3R enantiomer CP-96,344, which is not an NK1 receptor antagonist (IC50 > 10 microM), were evaluated for antinociceptive and anti-inflammatory activities in several classical models of pain and inflammation in the rat. Both CP-96,345 and CP-96,344 reduced carrageenin-induced paw oedema and hyperalgesia, and attenuated the second phase of formalin-induced paw licking with equal potency. These results indicate that NK1 antagonism is not responsible for the activity of (+/-)-CP-96,345 in the above animal models.


Asunto(s)
Compuestos de Bifenilo/farmacología , Inflamación/tratamiento farmacológico , Dolor/tratamiento farmacológico , Receptores de Neurotransmisores/antagonistas & inhibidores , Análisis de Varianza , Animales , Sitios de Unión , Modelos Animales de Enfermedad , Edema/inducido químicamente , Masculino , Dimensión del Dolor , Ratas , Ratas Sprague-Dawley , Receptores de Neuroquinina-2 , Estereoisomerismo
2.
Anal Sci ; 17(4): 519-22, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11990569

RESUMEN

An analytical method, referred to as "derivatization-electron probe X-ray micro-analysis (XMA)", has been developed to determine the distribution of a small amount of the functional groups in a polymer. The suitable conditions for the derivatization reaction with epoxy groups, which contribute to the hardening reactions of polymers, were investigated. It was found that epoxy groups in polymers were derivatized selectively using gas-phase esterification with hydrochloric acid (HCI). The most suitable amount of HCl in a 50 ml vial was 300 microl. After setting a sample in the vessel without directly contacting the reagent, by reacting the reagent and the sample at 25 degrees C for 1 h, the highest reaction yield and selectivity were obtained. By derivatization-XMA using this reaction condition, the measurement of the distribution of epoxy groups in the polymer became feasible. Actual applications to a depth analysis of epoxy groups in the hardened acrylic coating and epoxy resin proved that this method is useful for the characterization of polymers and for the study of the hardening reaction of polymers.

9.
Nucleic Acids Symp Ser ; (42): 201-2, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10780449

RESUMEN

Rme1p is a zinc-finger protein and has a pivotal role in control of meiosis in Saccharomyces cerevisiae. The DNA binding domain of Rme1p consists of three zinc-finger segments and the C-terminal 16 amino acid residues (called C-TR). To examine the role of C-TR, a series of mutant Rme1p fused with maltose binding protein (MBP) were constructed, purified, and characterized, in terms of the DNA binding ability. The basic amino acid residues R287 and K290, and the hydrophobic residues F288, L292, 1295, and L296 play an important role for DNA binding, suggesting that the C-TR forms an amphipathic alpha-helix. Also, it was shown that the mutations in the basic amino acid residues abolish the repression and inhibition of spore formation by Rme1p in vivo. Hence, the C-TR is important for in vivo function of Rme1p.


Asunto(s)
ADN/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Represoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Secuencia de Consenso , ADN/química , Proteínas Fúngicas/química , Meiosis , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/metabolismo , Mutación Puntual , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/citología , Dedos de Zinc
10.
Anal Chem ; 73(10): 2245-53, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11393848

RESUMEN

Chemical structural analysis of tape-stripped surfaces at dark spots growing in organic electroluminescent (EL) devices during exposure to the atmosphere was done by time-of-flight secondary ion mass spectrometry (OF-SIMS). The EL devices consist of indium-tin-oxide, triphenylamine-tetramer, tris(8-hydroxyquinoline)aluminum (Alq3), and a Mg-Ag cathode deposited in order under vacuum on a glass substrate. It was found that the interface between the Alq3 layer and the Mg-Ag cathode was exposed as a result of tape-stripping, where a large number of dark spots were observed on both sides. Secondary ion images of O-, Mg+, and Alq2+ were observed from the dark spots on the cathode side. On the other hand, Mg+ and O- images with a nucleus in the center were observed from the Alq3 side. It is concluded from the results that the constituent element Mg of the cathode was oxidized at the interface adjacent to the Alq3 layer during exposure to the atmosphere, forming a dark spot with a nucleus in the center. Finally, it was confirmed that the TOF-SIMS analysis of the tape-stripped surface is useful for the analysis of the mechanism of dark spot formation.

11.
Chem Pharm Bull (Tokyo) ; 39(9): 2395-9, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1804554

RESUMEN

Saponin-permeabilized polymorphonuclear leukocytes (PMNs) released beta-glucuronidase, a lysosomal enzyme, dose-dependently in response to cupric phenanthroline (CuPh), a mild oxidant, which catalyzes the formation of disulfide bridges. The beta-glucuronidase release induced by CuPh was inhibited by ethylene glycol bis(beta-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA). Both dithiothreitol (DTT) and N-(6-aminohexyl)-5-chloro-naphthalene sulfonamide (W-7) also inhibited the beta-glucuronidase release induced by CuPh. CuPh elicited a decrease in protein-bound free sulfhydryls simultaneously, and this decrease was not restored by EGTA treatment. CuPh inhibited Ca2+ uptake into Ca2+ store sites, and promoted a Ca2+ efflux from Ca2+ store sites. It also inhibited Ca(2+)-adenosine triphosphatase (ATPase) activity in permeable PMNs. DTT, a sulfhydryl reducing agent, suppressed both the beta-glucuronidase release and the Ca2+ uptake in CuPh-treated permeable PMNs. On the other hand, chloromercuriphenylsulfonic acid (CMPS), a sulfhydryl modifier, decreased the amount of free sulfhydryls in protein and released beta-glucuronidase in permeable PMNs dose-dependently, but EGTA did not inhibit either reaction. Neither CuPh nor CMPS released beta-glucuronidase from intact PMNs. These results indicate that both CuPh and CMPS act on intra-PMN target molecules to exert their influence, but the involved mechanisms are different in nature. Alteration in calcium movement is responsible for the beta-glucuronidase release in the CuPh-treated permeable PMNs.


Asunto(s)
Glucuronidasa/sangre , Neutrófilos/enzimología , Fenantrolinas/farmacología , Saponinas/farmacología , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Cobayas , Masculino , Neutrófilos/fisiología
12.
J Biol Chem ; 276(40): 37680-5, 2001 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11466318

RESUMEN

Rme1p plays important roles in the control of meiosis and in cell cycle progression through binding to upstream regions of IME1 and CLN2 in Saccharomyces cerevisiae. Rme1p has three zinc finger segments, and two of them are atypical. To determine DNA binding domain of Rme1p, a series of Rme1p derivatives fused with maltose-binding protein were purified and characterized by gel mobility shift assay. We show that not only three zinc fingers, but also the neighboring C-terminal region is essential for DNA binding. Mutational analysis of this region revealed that basic residues Arg-287, Lys-290, and Arg-291 and the hydrophobic residues Phe-288, Leu-292, Ile-295, and Leu-296 are critical for DNA binding. In addition, double substitutions by proline at Asn-289 and Lys-293, each of which was not essential for DNA binding, abolished DNA binding. These results suggest that the C-terminal segment forms an amphipathic helical structure. Furthermore, it was shown that the mutations in the important basic residues abolish or impair Rme1p function in vivo for repression and inhibition of spore formation. Thus, the C-terminal segment is essential and acts as a novel accessory domain for DNA binding by zinc fingers.


Asunto(s)
ADN/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Represoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Eliminación de Gen , Datos de Secuencia Molecular , Mutación , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Homología de Secuencia de Aminoácido , Dedos de Zinc
13.
Nucleic Acids Symp Ser ; (37): 175-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9586056

RESUMEN

A series of deletion mutants of the yeast Zn-finger protein Rme1p (Repressor of Meiosis) fused with maltose binding protein (MBP) were constructed, purified, and characterized to examine the DNA binding domain. It was shown by gel retardation assay that the DNA binding domain of Rme1p was attributed to C-terminal amino acid residues 171 to 300. All three Zn-fingers are involved in the DNA binding domain, but they are not sufficient for DNA binding ability. Notably, the C-terminal region (residues 285-300) is essential for DNA binding. Provided that the region folds into alpha-helix, the basic amino acid residues may form a ridge on one side of the helix, whereas the hydrophobic residues may form it on the other side. Thus, the DNA binding domain of Rme1p would be dissected two regions. The roles of C-terminal region in DNA recognition will be discussed.


Asunto(s)
Proteínas Fúngicas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Secuencia de Consenso , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/química , Meiosis , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Oligodesoxirribonucleótidos , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Dedos de Zinc
14.
Clin Exp Immunol ; 126(1): 165-72, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11678914

RESUMEN

The splicing isoform of HLA-G that is expressed in xenogeneic cells, and its effect on NK-mediated direct cytotoxicity was examined, using stable Chinese hamster ovary (CHO) cell or swine endothelial cell (SEC) transfectants. cDNAs of HLA-G (G1 and G3) and human beta2-microglobulin were prepared and subcloned into the expression vector, pCXN. The transfected HLA-G1 was easily expressed on SEC, and co-transfection with human beta2-microglobulin led to an enhanced level of HLA-G1 expression, as evidenced by flow cytometry. The expressed HLA-G1 significantly suppressed NK-mediated SEC cell lysis, which is an in vitro delayed-type rejection model of a xenograft. On the other hand, the swine leucocyte antigen (SLA) class I molecules could be up-regulated as the result of the transfection of human beta2-microglobulin, but did not down-regulate human NK-mediated SEC lysis. The HLA-G3 was not expressed on CHO and SEC in contrast to HLA-G1, as the result of the transfection. The gene introduction of HLA-G3 in SEC showed no protective effect from human NK cells. However, indirect evidence demonstrated that HLA-G3 transfection resulted in HLA-E expression, but not itself, when transfected to the human cell line, 721.221, thus providing some insight into its natural function in human cells. The present findings suggest that the expression of HLA-G1 on the cell surface could serve as a new approach to overcoming NK-mediated immunity to xenografts.


Asunto(s)
Citotoxicidad Inmunológica , Endotelio/inmunología , Antígenos HLA/fisiología , Antígenos de Histocompatibilidad Clase I/fisiología , Células Asesinas Naturales/inmunología , Porcinos/inmunología , Trasplante Heterólogo/inmunología , Animales , Western Blotting , Células CHO , Línea Celular , Cricetinae , Pruebas Inmunológicas de Citotoxicidad , Citometría de Flujo , Antígenos HLA/genética , Antígenos HLA-G , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Oligopéptidos , Péptidos/genética , ARN Mensajero/biosíntesis , Transfección
15.
Cytokine ; 5(5): 506-11, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8142607

RESUMEN

A full-length rat gro cDNA containing the signal sequence was inserted to a plasmid/phage vector pTD-lacs which had the Escherichia coli alkaline phosphatase leader sequence down-stream of the lac promoter. After removal of the gro signal sequence by site-directed mutagenesis, the vector was introduced to E. coli JM109. The cells grown in the presence of isopropyl beta-D-thiogalactopyranoside were found to contain the recombinant mature rat Gro protein in the periplasmic space. The protein was released from the cells by osmotic shock, and could be purified to homogeneity from the periplasmic fluid by a single-step procedure using reverse phase high performance liquid chromatography. By similar procedures, recombinant human Gro alpha could be obtained. In each case, about 10 mg of purified cytokine were obtained from 1 litre of bacterial culture.


Asunto(s)
Quimiocinas CXC , Factores Quimiotácticos/genética , Sustancias de Crecimiento/genética , Péptidos y Proteínas de Señalización Intercelular , Animales , Secuencia de Bases , Quimiocina CXCL1 , Factores Quimiotácticos/biosíntesis , Escherichia coli , Expresión Génica , Vectores Genéticos , Sustancias de Crecimiento/biosíntesis , Humanos , Datos de Secuencia Molecular , Ratas , Proteínas Recombinantes/biosíntesis
16.
Biochem Biophys Res Commun ; 265(2): 556-62, 1999 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-10558908

RESUMEN

The cell membrane-bound forms of mini-factor H with 1-4 short consensus repeats (fH-PI) and factor I (fI-PI) were constructed. Swine endothelial cell (SEC) lines and Chinese hamster ovary (CHO) cell expressing fH-PI or fI-PI were established and confirmed by flow cytometry. The cell lysate of the SEC line expressing fH-PI showed strong cofactor activity for the cleavage of C3b, and fI-PI demonstrated the protease activity for C4b and C3b not only in the fluid phase but also on the cell membrane. In addition, fH-PI blocked human complement-mediated cell lysis by approximately 30-40%. An SEC line with a low expression of fI-PI showed a weak inhibition of cell lysis in human serum, whereas a CHO cell transfectant with a high expression of fI-PI showed over a 60% inhibition of cell lysis. The results suggest that fH-PI and fI-PI have potential for use in clinical xenotransplantation.


Asunto(s)
Factor H de Complemento/metabolismo , Fibrinógeno/metabolismo , Animales , Secuencia de Bases , Antígenos CD55/genética , Antígenos CD55/metabolismo , Células CHO , Línea Celular , Membrana Celular/metabolismo , Activación de Complemento , Complemento C3/metabolismo , Complemento C4/metabolismo , Factor H de Complemento/química , Factor H de Complemento/genética , Cricetinae , Cartilla de ADN/genética , Fibrinógeno/química , Fibrinógeno/genética , Rechazo de Injerto/prevención & control , Humanos , Modelos Biológicos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Porcinos , Transfección , Trasplante Heterólogo
17.
J Biol Chem ; 276(42): 39310-9, 2001 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-11486004

RESUMEN

We have been successful in generating several lines of transgenic mice and pigs that contain the human beta-d-mannoside beta-1,4-N-acetylglucosaminyltransferase III (GnT-III) gene. The overexpression of the GnT-III gene in mice and pigs reduced their antigenicity to human natural antibodies, especially the Galalpha1-3Galbeta1-4GlcNAc-R, as evidenced by immunohistochemical analysis. Endothelial cell studies from the GnT-III transgenic pigs also revealed a significant down-regulation in antigenicity, including Hanganutziu-Deicher antigen, and dramatic reductions in both the complement- and natural killer cell-mediated pig cell lyses. Changes in the enzymatic activities of other glycosyltransferases, such as alpha1,3-galactosyltransferase, GnT-IV, and GnT-V, did not support cross-talk between GnT-III and these enzymes in the transgenic animals. In addition, we demonstrated the effect of GnT-III in down-regulating the xenoantigen of pig heart grafts, using a pig to cynomolgus monkey transplantation model, suggesting that this approach may be useful in clinical xenotransplantation in the future.


Asunto(s)
Antígenos Heterófilos/química , Antígenos Heterófilos/genética , N-Acetilglucosaminiltransferasas/metabolismo , Animales , Animales Modificados Genéticamente , Línea Celular , Regulación hacia Abajo , Femenino , Citometría de Flujo , Glicosiltransferasas/metabolismo , Trasplante de Corazón , Humanos , Inmunohistoquímica , L-Lactato Deshidrogenasa/metabolismo , Macaca fascicularis , Masculino , Ratones , Regiones Promotoras Genéticas , Porcinos , Distribución Tisular , Trasplante Heterólogo
18.
Anim Genet ; 31(6): 376-84, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11167524

RESUMEN

In order to locate the genetic regions in the swine genome that are responsible for economically important traits, a resource population has been constructed by mating two female Meishan pigs with a male Göttingen miniature pig. In subsequent generations, 265 F2 offspring were produced from two F1 males and 19 F1 females. The F2 offspring were scored for eight traits including growth rate, teat number, vertebra number and backfat thickness, and genotyped for 318 genetic markers spanning the swine genome. Least-square analysis revealed quantitative trait loci (QTL) effects for vertebra number on chromosomes 1 and 2; for teat number on chromosomes 1 and 7; for birth weight on chromosome 1; for average daily gain between 4 and 13 weeks of age on chromosomes 9 and 10; for backfat thickness on chromosome 7; and for backskin thickness on chromosome 3.


Asunto(s)
Cruzamientos Genéticos , Carácter Cuantitativo Heredable , Porcinos Enanos/genética , Animales , Femenino , Masculino
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