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1.
Zhonghua Fu Chan Ke Za Zhi ; 58(7): 526-535, 2023 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-37474326

RESUMO

Objective: To compare the effects and safety of dydrogesterone (DG) and medroxyprogesterone acetate (MPA) on the treatment in patients with endometrial hyperplasia without atypia (EH). Methods: This was a single-center, open-label, prospective non-inferior randomized controlled phase Ⅲ trial. From February 2019 to November 2021, patients with EH admitted to the Obstetrics and Gynecology Hospital of Fudan University were recruited. Enrolled patients were stratified according to the pathological types of simple hyperplasia (SH) or complex hyperplasia (CH), and were randomised to receive MPA or DG. Untill May 14, 2022, the median follow-up time after complete response (CR) was 9.3 months (1.1-17.2 months). The primary endpoint was the 6-month CR rate (6m-CR rate). The secondary endpoints included the 3-month CR rate (3m-CR rate), adverse events rate, recurrence rate, and pregnancy rate in one year after CR. Results: (1) A total of 292 patients with EH were enrolled in the study with the median age of 39 years (31-45 years). A total of 135 SH patients were randomly assigned to MPA group (n=67) and DG group (n=68), and 157 CH patients were randomly assigned to MPA group (n=79) and DG group (n=78). (2) Among 292 patients, 205 patients enrolled into the primary endpoint analysis, including 92 SH patients and 113 CH patients, with 100 patients in MPA group and 105 in DG group, respectively. The 6m-CR rate of MPA group and DG group were 90.0% (90/100) and 88.6% (93/105) respectively, and there were no statistical significance (χ2=0.11, P=0.741), with the rate difference (RD) was -1.4% (95%CI:-9.9%-7.0%). Stratified by the pathology types, the 6m-CR rate of SH patients was 93.5% (86/92), and MPA group and DG group were respectively 91.1% (41/45) and 95.7% (45/47); and the 6m-CR rate of CH patients was 85.8% (97/113), and MPA group and DG group were 89.1% (49/55) and 82.8% (48/58) respectively. The 6m-CR rates of the two treatments had no statistical significance either (all P>0.05). A total of 194 EH patients enrolled into the secondary endpoint analysis, including 88 SH patients and 106 CH patients, and 96 patients in MPA group and 98 in DG group, respectively. The 3m-CR rate of SH patients were 87.5% (77/88), while the 3m-CR rates of MPA group and DG group were 90.7% (39/43) and 84.4% (38/45), respectively; the 3m-CR rate of CH patients was 66.0% (70/106), and MPA group and DG group had the same 3m-CR rate of 66.0% (35/53). No statistical significance was found between the two treatments both in SH and CH patients (all P>0.05). (3) The incidence of adverse events between MPA group and DG group had no statistical significance (P>0.05). (4) A total of 93 SH patients achieved CR, and the cumulative recurrence rate in one year after CR were 5.9% and 0 in MPA group and DG group, respectively. While 112 CH patients achieved CR, and the cumulative recurrence rate in one year after CR were 8.8% and 6.5% in MPA group and DG group, respectively. There were no statistical significance between two treatment groups (all P>0.05). Among the 93 SH patients, 10 patients had family planning but no pregnancy happened during the follow-up period. Among the 112 CH patients, 21 were actively preparing for pregnancy, and the pregnancy rate and live-birth rate in one year after CR in MPA group were 7/9 and 2/7, while in DG group were respectively 4/12 and 2/4, and there were no statistical significance in pregnancy rate and live-birth rate between the two treatment groups (all P>0.05). Conclusions: Compared with MPA, DG is of good efficacy and safety in treating EH. DG is a favorable alternative treatment for EH patients.


Assuntos
Hiperplasia Endometrial , Acetato de Medroxiprogesterona , Feminino , Humanos , Adulto , Acetato de Medroxiprogesterona/efeitos adversos , Hiperplasia Endometrial/patologia , Didrogesterona/efeitos adversos , Hiperplasia , Estudos Prospectivos
2.
Pharmacogenetics ; 2(1): 25-31, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1302040

RESUMO

Twelve Caucasian healthy men and women, of whom six were poor metabolizers (PMs) and six were extensive metabolizers (EMs) of S-mephenytoin, together with 13 Chinese healthy men and women (five PMs and eight EMs), received a single oral 20 mg dose of omeprazole. Plasma levels of omeprazole and its two main metabolites, omeprazole sulphone and hydroxyomeprazole, were determined by HPLC. The mean (+/- SD) area under the plasma concentration-time curve (AUC) for omeprazole was 11.1 +/- 2.6 and 0.9 +/- 0.4 microM h in the Caucasian PMs and EMs, respectively. Corresponding values for elimination half-life were 2.3 +/- 0.4 and 0.7 +/- 0.4 h. In the Chinese PMs and EMs the AUC of omeprazole as 13.3 +/- 5.6 and 2.6 +/- 1.8 microM h. The AUCs of omeprazole were significantly higher in the Chinese EMs than in the Caucasian EMs possibly due to the higher proportion of heterozygotes in the former than in the latter group. The elimination half-life in the Chinese PMs and EMs was 2.4 +/- 0.2 and 0.8 +/- 0.2 h--similar to the observations in the Caucasian subjects. The maximum plasma concentration of hydroxyomeprazole was five-fold and four-fold higher in EMs compared to PMs among Caucasians and Chinese, respectively. The elimination half-life of the hydroxy metabolite was also longer in PMs than in EMs in both populations. The ratio between AUC for omeprazole and AUC for hydroxyomeprazole was 11.9 +/- 2.1 and 0.6 +/- 0.1 in Caucasian PMs and EMs, respectively. Corresponding values in the Chinese were 13.1 +/- 2.9 and 1.6 +/- 0.5.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Povo Asiático/genética , Mefenitoína/metabolismo , Omeprazol/metabolismo , População Branca/genética , Adulto , Feminino , Meia-Vida , Humanos , Hidroxilação , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Omeprazol/sangue , Polimorfismo Genético
3.
Clin Pharmacol Ther ; 34(4): 516-20, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6617075

RESUMO

Amitriptyline AT demethylation to nortriptyline NT was determined in nine healthy subjects who had been phenotyped with respect to debrisoquine D hydroxylation capacity. AT demethylation was calculated from the ratio between the plasma AUCs of NT after single oral doses of AT and NT. Plasma clearance of AT by demethylation did not correlate with the ratio between D and 4-hydroxy-D in urine (rs = -0.55).


Assuntos
Amitriptilina/metabolismo , Adulto , Amitriptilina/sangue , Debrisoquina/metabolismo , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Nortriptilina/sangue , Fumar
4.
Cancer Gene Ther ; 6(1): 21-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10078960

RESUMO

Replication-competent adenoviruses (Ads) were used for oncolytic virotherapy soon after they were discovered. Recently mutated and genetically engineered Ads have been shown to selectively lyse tumor cells. We have split the human Ad type 5 genome into two defective viruses that complement each other only in certain tumor cells. The genome of one of these vectors, GT5610, contains only the minimal viral elements required in cis for replication and packaging and the E1 viral genes with E1A under the control of the human alpha-fetoprotein promoter. This "controlled" vector has a capacity for 30 kilobases of foreign DNA. The supplemental vector, AdHbeta, contains all adenoviral genes except for E1. Both vectors were designed to carry heterologous reporter genes whose expression could be detected throughout the tumor. Coinfection of hepatocarcinoma cells that have the capacity to transcribe genes under the control of the alpha-fetoprotein promoter leads to cell lysis and copropagation. The oncolytic spread of these complementary vectors in vivo was demonstrated by the intratumoral injection of human hepatocarcinomas xenografted in severe combined immunodeficient (SCID) mice. This system presents safety and gene capacity features that could yield a therapeutic advantage over oncolysis by a single virus.


Assuntos
Adenoviridae/genética , Terapia Genética/métodos , Vetores Genéticos , Adenocarcinoma/metabolismo , Animais , Carcinoma Hepatocelular/terapia , Relação Dose-Resposta a Droga , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes , Camundongos , Camundongos SCID , Fatores de Tempo , Células Tumorais Cultivadas , alfa-Fetoproteínas/metabolismo
5.
Thromb Haemost ; 82(2): 562-71, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10605752

RESUMO

To achieve efficient delivery and sustained expression of the human factor VIII cDNA in vivo, a minimal-adenoviral (mini-Ad) vector system was developed. The system is composed of a mini-Ad vector with essential cis-elements (less than 1 kb) of the viral genome, an E1-deleted ancillary Ad with packaging attenuation, and an E1-complementing production cell line. Based on this system, MiniAdFVIII was generated to deliver a 27 kb expression cassette consisting of a full-length human factor VIII cDNA flanked by human albumin promoter and genomic sequences. The MiniAdFVIII vector mediated expression of functional human factor VIII in HepG2 and 293 cells. A single-dose intravenous injection of 10(11) viral particles in hemophilic mice of MiniAdFVIII produced a sustained high-level expression of human factor VIII (at 100-800 ng/ml up to 369 days) which corrected the FVIII-deficient phenotype. Safety studies of MiniAdFVIII showed that there were no significant toxic effects in mice and dogs after single intravessel doses of up to 3 x 10(11) and 6 x 10(12) viral particles, respectively. Studies for developing the MiniAdFVIII vector with a site-specific integration mechanism and progress in the development of a human factor VIII-tolerized mouse model for pre-clinical studies of MiniAdFVIII are reported. Further pre-clinical studies and product development of MiniAdFVIII for clinical trials are also discussed.


Assuntos
Adenoviridae/genética , Fator VIII/genética , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Hemofilia A/terapia , Animais , Modelos Animais de Doenças , Cães , Humanos , Camundongos
6.
J Virol Methods ; 68(2): 147-59, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9389404

RESUMO

The complementation of adenoviral vectors with large deletions in the viral genome was studied. The helper adenovirus used to complement these vectors contains a partial deletion of the packaging signal and the E1 region substituted by the lacZ gene. The effect of vector size on packaging efficiency was analysed in 293 cells using decreasingly shorter vectors expressing GFP from a CMV enhancer-beta-actin promoter. Vectors with longer genomes propagated more efficiently than shorter ones. Vectors containing only the packaging signal and the ITRs of Ad5, having all the viral genes replaced with unrelated sequences packaged as efficiently as vectors of the same size containing adenoviral DNA instead of exogenous DNA. The amounts of helper and vector produced in coinfected 293 cells exhibited the typical cycling fluctuation observed during serial propagation of a virus with defective interfering particles.


Assuntos
Adenoviridae/genética , Teste de Complementação Genética , Vetores Genéticos/química , Vírus Auxiliares/genética , Replicação Viral/genética , Adenoviridae/fisiologia , Proteínas E1 de Adenovirus/genética , Linhagem Celular , Deleção de Genes , Vetores Genéticos/biossíntese , Vírus Auxiliares/fisiologia , Humanos , Mutagênese Insercional , Sinais Direcionadores de Proteínas/genética , Inoculações Seriadas , Montagem de Vírus/genética
7.
Sheng Li Xue Bao ; 52(3): 179-84, 2000 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-11956559

RESUMO

This study was designed to investigate whether GABA is involved in the capacitation effect and hyperactivated motility (HAM). Spematozoa from fertile men and retired guinea pigs were washed in modified BWW of 45% 90% Percoll gradient with 26 mg BSA/ml and in low Ca(2+)-MCM of 30%-55%-85% Percoll gradient (approximately 23 micromol/L Ca(2+)) respectively. The samples were preincubated for 2 h under 5% CO2 in air at 38.5 with or without GABA, progesterone (P(4)), GABA(A) receptor agonists or antagonists, and then exposed to 1 micromol/L (for human) or 5 micromol/L (for guinea pigs) calcium ionophore A 23187 for 15 min. The capacitation effect and HAM were assessed by using the chlortetracycline (CTC) staining method and phase-contrast microscopy. Motility was 80% 85% after all additions. The results showed that addition of GABA or P(4) at 5 micromol/L to the incubation medium resulted in a significant increase in the sum of B (characteristic of capacitated cell) and AR (acrosome recation) pattern (65.9% and 61.7% respectively), corresponding to capacitated spermatozoa in human, as compared to the control (37.3%). Likewise, the capacitating effect of GABA on spermatozoa in guinea pigs showed a concentration-dependent increase from 1 to 10 micromol/L(AR: 27.0 +/- 1.9% to 51.6 +/-2.8%). In addition, P(4) potentiated the capacitating effect of GABA when combined with GABA in the capacitation stage. The capacitating effect of GABA was mimicked by a GABAA receptor agonist muscimol. However, this effect was completely blocked by a GABA(A) receptor antagonist (-)-bicuculline and a GABA(A)/Cl(-) receptor antagonist picrotoxin. Furthermore, GABA markedly increased the HAM of P(4) on guinea pig spermatozoa, which was mediated obviously by the influx of extracellular Ca(2+) because the GABA-induced AR could be prevented by EGTA. These results indicate that GABA and P(4) are involved in the capacitation of spermatozoa in both human and guinea pigs through a GABA(A) receptor-mediated mechanism.


Assuntos
Reação Acrossômica/efeitos dos fármacos , Progesterona/farmacologia , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/fisiologia , Ácido gama-Aminobutírico/farmacologia , Animais , Células Cultivadas , Cobaias , Humanos , Masculino , Espermatozoides/citologia
8.
Yao Xue Xue Bao ; 32(7): 481-4, 1997 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-11596270

RESUMO

The pharmacokinetics of diazepam (3 mg.kg-1, i.v.) in rabbits was studied after pretreatment with rifampin (RFP, 100 mg.kg-1.d-1 x 4), isoniazid (INH, 50 mg.kg-1.d-1 x 4) and RFP + INH. The results showed that RFP significantly increased cytochrome P-450 content, but the T 1/2 and AUC of diazepam were significantly decreased. The plasma clearance (CL) was increased in the RFP group. In the INH group the T 1/2 and AUC of diazepam were significantly increased and the CL was significantly decreased. However, cytochrome P-450 content and the pharmacokinetic parameters of diazepam were not changed in the RFP + INH group. Our results indicate that RFP induces the activity of hepatic microsomal enzymes and increases the metabolism of diazepam, INH inhibits the activity of hepatic microsomal enzymes and decreases the metabolism of diazepam in rabbits.


Assuntos
Diazepam/farmacocinética , Isoniazida/farmacologia , Rifampina/farmacologia , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Masculino , Microssomos Hepáticos/enzimologia , Coelhos , Distribuição Aleatória
11.
Proc Natl Acad Sci U S A ; 89(20): 9875-9, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1409716

RESUMO

RNase P from the mitochondria of Saccharomyces cerevisiae was purified to near homogeneity > 1800-fold with a yield of 1.6% from mitochondrial extracts. The most abundant protein in the purified fractions is, at 105 kDa, considerably larger than the 14-kDa bacterial RNase P protein subunits. Oligonucleotides designed from the amino-terminal sequence of the 105-kDa protein were used to identify and isolate the 105-kDa protein-encoding gene. Strains carrying a disruption of the gene for the 105-kDa protein are viable but respiratory deficient and accumulate mitochondrial tRNA precursors with 5' extensions. As this is the second gene known to be necessary for yeast mitochondrial RNase P activity, we have named it RPM2 (for RNase P mitochondrial).


Assuntos
Endorribonucleases/química , Mitocôndrias/enzimologia , RNA Catalítico/química , Sequência de Aminoácidos , Sequência de Bases , Endorribonucleases/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Genes Fúngicos , Dados de Sequência Molecular , Peso Molecular , Mutagênese Insercional , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos/química , RNA Catalítico/isolamento & purificação , Ribonuclease P , Saccharomyces cerevisiae , Relação Estrutura-Atividade
12.
J Biol Chem ; 269(18): 13361-6, 1994 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-8175766

RESUMO

ATP (CTP):tRNA nucleotidyltransferase catalyzes the addition of the CCA end to tRNAs. In yeast, nucleotidyltransferase is encoded by the CCA1 gene and is localized to three cellular compartments: mitochondria, nucleus, and cytosol. There are three in-frame ATGs near the 5' end of the CCA1 open reading frame. Primer extension experiments show multiple transcription initiation sites upstream of ATG1 and between ATG1 and ATG2. Fractionation of cells carrying a CCA1-COXIV fusion gene demonstrates that all three in-frame AUGs are used as sites of initiation of translation. Therefore, both transcription of CCA1 mRNA with heterogeneous 5' ends and translation from downstream AUGs in CCA1 mRNAs play a role in the synthesis of three nucleotidyltransferase isozymes. Protein initiating from AUG1 is required for mitochondrial protein synthesis and, like many other proteins targeted to mitochondria, it is processed at the amino terminus upon import into the organelle. The shorter proteins arising from AUG2 and AUG3 provide nuclear/cytosol activity.


Assuntos
Códon , Isoenzimas/biossíntese , Biossíntese de Proteínas , RNA Nucleotidiltransferases/biossíntese , Saccharomyces cerevisiae/enzimologia , Transcrição Gênica , Sequência de Aminoácidos , Sequência de Bases , Carbono , Núcleo Celular/enzimologia , Citosol/enzimologia , DNA Fúngico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fermentação , Genes Fúngicos , Isoenzimas/genética , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Plasmídeos , RNA Nucleotidiltransferases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
13.
Arch Biochem Biophys ; 377(2): 219-27, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10845697

RESUMO

Hepatitis delta virus (HDV) is a satellite virus of the hepatitis B virus (HBV) which provides the surface antigen for the viral coat. The RNA genome of HDV encodes two proteins, the small delta antigen and the large delta antigen, which differ only with the latter having an additional 19 amino acids at the C-terminus. Previously, we have shown that dAg24-50, a synthetic peptide corresponding to residues 24-50 of the N-terminal leucine-repeat region of hepatitis delta antigen, binds to the viral RNA and forms an alpha-helical conformation in TFE-containing solution. However, it exhibited low alpha-helicity (less than 5%) in the absence of TFE. In order to obtain biologically active delta antigen peptides with higher structural stability in solution, an N-capping 21-residue polypeptide corresponding to residues 24-38 of hepatitis delta antigen (dAg(Cap24-38am)) was synthesized and, surprisingly, its solution structure was found to be a stable alpha-helix (64%) by circular dichroism and 1H NMR techniques. Moreover, the structure of the capping box shows the characteristic L-shaped bend perpendicular to the helix axis. This structural knowledge provides a molecular basis for understanding the role of the N-terminal leucine-repeat region of hepatitis delta antigen and has a significant potential for the development of diagnostic and therapeutic methods for HDV.


Assuntos
Antígenos de Hepatite/química , Vírus Delta da Hepatite/química , Leucina/química , Peptídeos/química , Sequência de Aminoácidos , Dicroísmo Circular , Antígenos da Hepatite delta , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos
14.
J Biomol NMR ; 12(1): 183-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9729796

RESUMO

Hepatitis delta virus (HDV) is a satellite virus of the hepatitis B virus (HBV) which provides the surface antigen for the viral coat. Our results show that the N-terminal leucine-repeat region of hepatitis delta antigen (HDAg), encompassing residues 24-50, binds to the autolytic domain of HDV genomic RNA and attenuates its autolytic activity. The solution conformation of a synthetic peptide corresponding to residues 24-50 of HDAg as determined by two-dimensional 1H NMR and circular dichroism techniques is found to be an alpha-helix. The local helix content of this peptide was analyzed by NOEs and coupling constants. Mutagenesis studies indicate that Lys38, Lys39, and Lys40 within this alpha-helical peptide may be directly involved in RNA binding. A structural knowledge of the N-terminal leucine-repeat region of HDAg thus provides a molecular basis for understanding its role in the interaction with RNA.


Assuntos
DNA Viral/química , DNA Viral/metabolismo , Antígenos de Hepatite/química , Antígenos de Hepatite/metabolismo , Vírus Delta da Hepatite/genética , Leucina , Fragmentos de Peptídeos/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Sítios de Ligação , Dicroísmo Circular , Vírus Delta da Hepatite/metabolismo , Antígenos da Hepatite delta , Hidrogênio , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular/métodos , Fragmentos de Peptídeos/síntese química
15.
Proteins ; 37(1): 121-9, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10451556

RESUMO

Hepatitis delta virus (HDV) is a satellite virus of the hepatitis B virus (HBV) which provides the surface antigen for the viral coat. The RNA genome of HDV encodes two proteins: the small delta antigen and the large delta antigen. The two proteins resemble each other except for the presence of an additional 19 amino acids at the C terminus of the latter species. We have found that the N-terminal leucine-repeat region of hepatitis delta antigen (HDAg) binds to the autolytic domain of HDV genomic RNA and attenuates its autolytic activity. A 27-residue polypeptide corresponding to residues 24-50 of HDAg, designated dAg(24-50), was synthesized, and its solution structure was found to be an alpha-helix by circular dichroism and (1)H-nuclear magnetic resonance (NMR) techniques. Binding affinity of dAg(24-50) with HDV genomic RNA was found to increase with its alpha-helical content, and it was further confirmed by modifying its N- and C-terminal groups. Furthermore, the absence of RNA binding activity in the mutant peptides, dAgM(24-50am) and dAgM(Ac24-50am), in which Lys38, Lys39, and Lys40 were changed to Glu, indicates a possible involvement of these residues in their binding activity. Structural knowledge of the N-terminal leucine-repeat region of HDAg thus provides a molecular basis for the understanding of its role in the interaction with RNA. Proteins 1999;37:121-129.


Assuntos
Antígenos de Hepatite/química , Vírus Delta da Hepatite/genética , Leucina/química , RNA/metabolismo , Sequência de Aminoácidos , Dicroísmo Circular , Antígenos da Hepatite delta , Humanos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Alinhamento de Sequência
16.
J Biomol NMR ; 16(4): 303-12, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10826882

RESUMO

X-linked agammaglobulinemia (XLA), an inherited disease, is caused by mutations in the Bruton's tyrosine kinase (BTK). The absence of functional BTK leads to failure of B cell differentiation which incapacitates antibody production in XLA patients leading to, sometimes lethal, bacterial infections. Point mutation in the BTK gene that leads to deletion of C-terminal 14 aa residues of BTK SH3 domain was found in one patient family. To understand the role of BTK in B cell development, we have determined the solution structure of BTK SH3 domain complexed with a proline-rich peptide from the protein product of c-cbl protooncogene (p120cbl). Like other SH3 domains, BTK SH3 domain consists of five beta-strands packed in two beta-sheets forming a beta-barrel-like structure. The rmsd calculated from the averaged coordinates for the BTK SH3 domain residues 218-271 and the p120cbl peptide residues 6-12 of the complex was 0.87 A (+/-0.16 A) for the backbone heavy atoms (N, C, and Calpha) and 1.64 A (+/-0.16 A) for all heavy atoms. Based on chemical shift changes and inter-molecular NOEs, we have found that the residues located in the RT loop, n-Src loop and helix-like loop between beta4 and beta5 of BTK SH3 domain are involved in ligand binding. We have also determined that the proline-rich peptide from p120cbl binds to BTK SH3 domain in a class I orientation. These results correlate well with our earlier observation that the truncated BTK SH3 domain (deletion of beta4, beta5 and the helix-like loop) exhibits weaker affinity for the p120cbl peptide. It is likely that the truncated SH3 domain fails to present to the ligand the crucial residues in the correct context and hence the weaker binding. These results delineate the importance of the C-terminus in the binding of SH3 domains and also indicate that improper folding and the altered binding behavior of mutant BTK SH3 domain likely lead to XLA.


Assuntos
Prolina/química , Proteínas Tirosina Quinases/química , Proteínas Proto-Oncogênicas/química , Ubiquitina-Proteína Ligases , Domínios de Homologia de src , Tirosina Quinase da Agamaglobulinemia , Sítios de Ligação , Humanos , Ressonância Magnética Nuclear Biomolecular , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-cbl , Soluções/química
17.
Int J Cancer ; 81(3): 325-9, 1999 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-10209943

RESUMO

Polymorphisms in xenobiotic metabolizing enzymes have been implicated in inter-individual and inter-ethnic differences in cancer susceptibilty. Several studies have indicated an association between variant alleles of the human CYP1A1, CYP2E1 and GSTM1 genes and lung cancer. Activity of microsomal epoxide hydrolase (HYL1) has also been associated with lung cancer, and 2 variant alleles causing amino acid substitutions have been described. We have investigated genetic polymorphisms of the CYP1A1, CYP2E1, GSTM1 and HYL1 genes in 76 Chinese lung cancer patients and 122 healthy Chinese subjects. The allele frequency of the CYP1A1*2B allele was 0.21 among lung cancer patients and 0.20 in the reference group, whereas the corresponding values for the CYP1A1*2A allele were 0.34 and 0.36. The CYP2E1*5B and CYP2E1*6 alleles were less frequent among the cancer patients (0.20 and 0.22) compared with healthy subjects (0.25 and 0.26). The frequency distribution of the HYL1*2 allele was 0.49 among lung cancer patients and 0.42 in the reference group, and the corresponding frequencies for the HYL1*3 allele were 0.13 and 0.10. The homozygous GSTM1*0 genotype was found in 64% of lung cancer patients and in 66% of healthy subjects. Among heavy smokers, the frequency was 73%. The differences in the distribution of variant CYP1A1, CYP2E1 and GSTM1 alleles in lung cancer patients and healthy controls were not statistically significant. Our results indicate that the polymorphisms investigated are of minor importance as genetic susceptibility markers for lung cancer in this population. An increased risk for lung cancer in subjects carrying the HYL*3 allele was observed and suggests that polymorphism in this gene might possibly be a susceptibility factor in the Chinese population.


Assuntos
Neoplasias Pulmonares/genética , Polimorfismo Genético , Xenobióticos/metabolismo , Adulto , Idoso , Alelos , Sistema Enzimático do Citocromo P-450/genética , Epóxido Hidrolases/genética , Feminino , Genótipo , Glutationa Transferase/genética , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade
18.
Sci Sin B ; 26(8): 809-17, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6194560

RESUMO

This paper is to evidence that the antiviral effect of pppA2'P5'A2'P5'A(2'-5'P3A3) could cover a wide spectrum of viruses, the RNA viruses such as influenza H3N2/77, influenza H1N1/77, ECHO11, rhino, Sendai, Sindbis and VSV, and the DNA viruses such as herpes (type I). In addition, the antiviral effect of 2'-5'P3A3 on ECHO11 virus, as compared with other viruses, is more efficient than that of IFN. It seems likely that 2'-5'P3A3 plays an important role in the antiviral action of IFN. After comparing the action of 2'-5'P3A3 with interferon (IFN), it has appeared that the action of 2'-5'P3A3 is something parallel to that of IFN for most viruses. For a few viruses, however, considerable differences have been observed.


Assuntos
Nucleotídeos de Adenina/farmacologia , Interferons/farmacologia , Oligonucleotídeos/farmacologia , Oligorribonucleotídeos/farmacologia , Vírus/efeitos dos fármacos , Enterovirus/efeitos dos fármacos , Humanos , Sindbis virus/efeitos dos fármacos , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
19.
Ther Drug Monit ; 16(2): 214-5, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8009572

RESUMO

Two independent studies showed that the 5-hydroxylation, but not the sulfoxidation, of omeprazole is more rapid in extensive metabolizers (EMs) than in poor metabolizers (PMs) of S-mephenytoin. In Caucasian, Chinese, and Korean PMs, the mean oral clearances were similar and not significantly different (85, 73, and 59 ml h-1 kg-1, respectively). However, the geometric mean clearance in Caucasian EMs (950 ml h-1 kg-1) was higher than in both Chinese EMs (426 ml h-1 kg-1, p < 0.05) and Korean EMs (446 ml h-1 kg-1, p < 0.01). The incidence of PMs of S-mephenytoin is higher in Chinese (14.6%) and Koreans (12.6%) than in Swedish Caucasians (3.3%). Therefore, the proportion of heterozygous compared to homozygous EMs is higher in Orientals than in Caucasians. This might explain the higher clearance of omeprazole in Caucasian EMs compared to the clearance of omeprazole in Chinese and Korean EMs of S-mephenytoin.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Povo Asiático , Omeprazol/metabolismo , População Branca , Povo Asiático/genética , Citocromo P-450 CYP2C19 , Sistema Enzimático do Citocromo P-450/genética , Humanos , Oxigenases de Função Mista/genética , Fenótipo , População Branca/genética
20.
Arch Biochem Biophys ; 372(2): 309-14, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10600169

RESUMO

The solution structure and dynamics of G1TE, a nonphosphorylated cyclic peptide inhibitor for the Grb2 SH2 domain, was determined using two-dimensional NMR and simulated annealing methods. G1TE consists of 10 amino acids and a C-terminal Cys cyclized through its side-chain sulfur atom by a thioether linkage to its N terminus. The results indicate that G1TE assumes a circle-like shape in solution in which all the side chains are protruding outside, and none of the residues are involved in intramolecular hydrogen bonding. The average root-mean-square deviations were found to be 0.41 +/- 0.11 A for the backbone heavy atoms C, Calpha, and N, and 1.03 +/- 0.14 A for all heavy atoms in a family of 10 structures. (15)N relaxation measurements indicate that G1TE has rather restricted dynamics in the fast time scale within its backbone. However, residues Tyr3, Val6, and Gly7 may be involved in a possible conformational exchange. The structural comparison between G1TE in solution and the BCR-Abl phosphopeptide bound to Grb2 SH2 domain revealed that G1TE may form a larger circle-like binding surface than the BCR-Abl phosphopeptide in the bound form. Also, the restricted backbone dynamics of G1TE may result in a reduced loss of entropy and can compensate for the absence of a phosphate group at the Tyr3 position. These structural and dynamic properties of G1TE may provide a molecular basis for understanding its interactions with the Grb2 SH2 domain.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Peptídeos Cíclicos/química , Proteínas/antagonistas & inibidores , Proteínas/química , Domínios de Homologia de src , Sequência de Aminoácidos , Sítios de Ligação , Proteína Adaptadora GRB2 , Humanos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , Fosforilação , Conformação Proteica , Proteínas/metabolismo , Soluções , Relação Estrutura-Atividade , Temperatura , Termodinâmica
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