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1.
J Eur Acad Dermatol Venereol ; 21(10): 1404-12, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958849

RESUMO

OBJECTIVE: Clinical efficacy and safety of Polyphenon(R) E, a defined green tea extract, in external genital warts. DESIGN: Randomized, double-blind, placebo-controlled study for up to 12 weeks with a 12-week treatment-free follow-up. SETTING: Twenty-eight hospitals and practices in Germany and Russia. PATIENTS: Two hundred forty-two outpatients (125 men, 117 women) with 2 to 30 warts (total wart area, 12-600 mm(2)). Intervention(s) Topical application of Polyphenon E 10% Cream, Polyphenon E 15% Ointment or placebo to all external genital warts three times a day. MAIN OUTCOME MEASURE(S): Measurement of total wart area and local reactions/adverse events. RESULTS: For 15% ointment, statistically significant differences to placebo were achieved regarding complete clearance of all baseline external genital warts (61.0% vs. 40.5% in males, 56.8% vs. 34.1% in females; combined gender: P = 0.0066) and 75% to 100% clearance (80.8% vs. 51.8%; P = 0.0001) in both the intent-to-treat and per-protocol populations. For 10% cream, 53.8% males and 39.5% females achieved complete clearance. Recurrence rates 12 weeks after end of treatment were 10.6%, 11.8% and 10.3% for 15% ointment, 10% cream and placebo, respectively. Adverse events were observed in only 7.9% of patients, with no serious adverse events or deaths reported. Local skin reactions were generally mild to moderate and resolved with continued treatment without sequelae. CONCLUSIONS: Polyphenon(R) E 15% ointment, composed of a defined green tea extract, proved to be efficacious and safe for both gender in the treatment of external genital warts.


Assuntos
Catequina/análogos & derivados , Condiloma Acuminado/tratamento farmacológico , Adolescente , Adulto , Idoso , Catequina/química , Catequina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pomadas , Placebos , Prognóstico , Estatísticas não Paramétricas , Resultado do Tratamento
3.
Chem Biol Interact ; 135-136: 325-41, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11397399

RESUMO

1,3-Butadiene (BD) is a multisite carcinogen and is mutagenic in multiple tissues of B6C3F1 mice. BD is bioactivated to at least three directly mutagenic metabolites: 1,2-epoxybutene (EB), 1,2-epoxy-3,4-butanediol (EBD), and 1,2,3,4-diepoxybutane (DEB). However, the contribution of these individual metabolites to the carcinogenicity and in vivo mutatidnal spectrum of BD is uncertain. To assess the role of two BD metabolites EB and DEB in the in vivo mutagenicity of the parent compound BD, we examined the in vitro mutational spectra of EB and DEB in human and rodent cells. We also examined the in vivo mutagenicity and mutational spectrum of inhaled EB in the lung. In the bone marrow and spleen of B6C3F1 laci transgenic mice, BD-induced an increased frequency of the identical class of point mutations at A:T base pairs: AT-->GC transitions and AT-->TA transversions. BD exposure also induced an increased frequency of GC-->AT transitions in the spleen that was not observed in bone marrow, demonstrating tissue-specific differences in mutation spectrum. Exposure of Rat2 laci transgenic cells and human TK6 lymphoblasts to EB-induced an increased frequency of AT-->TA transversions. DEB exposure induced an increased frequency of AT-->TA transversions and partial deletions at hprt in human cells. In Rat laci transgenic cells, DEB was not mutagenic at laci but induced an increased frequency of micronuclei. In contrast to inhaled BD, inhaled DEB and EB were not mutagenic in the bone marrow or spleen. However, EB was mutagenic in the lungs. In the lung of mice, EB-induced specific increases in GC-->AT transitions, AT-->TA transversions, and deletion events. AT-->TA transversions are the most consistent mutation observed across biological systems following in vivo exposure to BD or in vitro exposures to EB and DEB. Although, BD exposure in mice induces chromosomal alterations and single base substitutions, the specific BD metabolite that induces the genetic events leading to tumors is uncertain. At present, it appears that only DEB can effectively induce this range of mutagenic events at levels of this metabolite that occur in the blood of mice exposed to BD. Detailed investigations to identify relevant biomarkers of BD exposure and response, particularly DNA adducts or lesions, that can be biologically linked to the range of genotoxic events known to occur in mice exposed to BD are needed.


Assuntos
Butadienos/metabolismo , Butadienos/toxicidade , Compostos de Epóxi/metabolismo , Compostos de Epóxi/toxicidade , Proteínas de Escherichia coli , Mutagênicos/metabolismo , Mutagênicos/toxicidade , Poluentes Atmosféricos/toxicidade , Animais , Proteínas de Bactérias/genética , Linhagem Celular , Feminino , Humanos , Repressores Lac , Masculino , Camundongos , Camundongos Transgênicos , Testes de Mutagenicidade , Ratos , Proteínas Repressoras/genética , Baço/efeitos dos fármacos
4.
Mutat Res ; 473(1): 37-49, 2001 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-11166025

RESUMO

1,3-Butadiene (BD) is carcinogenic and mutagenic in B6C3F1 mice. BD inhalation induces an increased frequency of specific base substitution mutations in the bone marrow and spleen of B6C3F1 lacI transgenic mice. BD is bioactivated to at least three mutagenic metabolites: 1,2-epoxybutene (EB), 1,2-epoxy-3,4-butanediol (EBD), and 1,2,3,4-diepoxybutane (DEB), however, the contribution of these individual metabolites to the in vivo mutational spectrum of BD is uncertain. In the present study, lacI transgenic mice were exposed by inhalation (6h per day, 5 days per week for 2 weeks) to 0 or 29.9ppm of the BD metabolite, EB to assess its contribution to the in vivo mutational spectrum of BD. No increase in lacI mutant frequency was observed in the bone marrow or spleen of EB-exposed mice. The lack of mutagenicity in the bone marrow or spleen likely relate to insufficient levels of EB reaching these tissues. The lacI mutant frequency was increased 2.7-fold in the lungs of EB-exposed mice (mean+/-S.D., 9.9+/-3.0x10(-5)) compared to air control mice (3.6+/-0.7x10(-5)). DNA sequence analysis of 65 and 66 mutants from the lungs of air control and EB-exposed mice, respectively, revealed an increase in the frequency of two categories of base substitution mutation and deletions. Like mice exposed to BD, EB-exposed mice had an increased frequency of A:T-->T:A transversions. However, in contrast to the BD mutational spectra, G:C-->A:T transitions at 5'-CpG-3' sequences, occurred with increased frequency in the EB-exposed mice. The increased frequency of deletions as well as the induction of two tandem mutations and a tandem deletion in the lungs of EB-exposed mice are also inconsistent with previous mutational spectra from BD-exposed mice or EB-exposed cells in culture. We hypothesize that the direct in vivo mutagenicity and further in situ metabolism of EB in the lungs of EB-exposed mice played a prominent role in the generation of the current mutational spectrum.


Assuntos
Proteínas de Bactérias/genética , Compostos de Epóxi/administração & dosagem , Proteínas de Escherichia coli , Pulmão/metabolismo , Mutagênese/efeitos dos fármacos , Mutagênese/genética , Proteínas Repressoras/genética , Administração por Inalação , Animais , Proteínas de Bactérias/efeitos dos fármacos , Medula Óssea/metabolismo , Análise Mutacional de DNA , Compostos de Epóxi/toxicidade , Feminino , Repressores Lac , Camundongos , Camundongos Transgênicos , Mutagênicos/administração & dosagem , Mutagênicos/toxicidade , Proteínas Repressoras/efeitos dos fármacos , Baço/metabolismo , Distribuição Tecidual
5.
Org Lett ; 1(8): 1303-5, 1999 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-10825979

RESUMO

[formula: see text] The diastereoselective synthesis of cis-2,5-disubstituted-3-methylenetetrahydrofurans via Pd(0)-catalyzed cyclization of 2-methylene-1,4-diols is described. Investigations into the scope of the reaction and its application toward the synthesis of amphidinolide K is reported.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Furanos/síntese química , Paládio/química , Catálise , Furanos/química , Macrolídeos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
6.
Mutat Res ; 401(1-2): 99-110, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9639685

RESUMO

1,3-Butadiene (BD) is carcinogenic and mutagenic in B6C3F1 mice. We determined the lacI mutant frequency and mutational spectrum in spleen following inhalation exposure to BD at levels that are known to induce tumors. B6C3F1 lacI transgenic mice were exposed to air or to 62.5, 625, or 1250 ppm BD for 4 weeks (6 h/day, 5 days/week) and euthanized 14 days after the last exposure. BD increased the lacI mutant frequency in spleen at all levels of BD examined. In BD-exposed mice, an increased frequency of G:C-->A:T transitions occurred at non-5'-CpG-3' sites. Exposure to BD in B6C3F1 lacI transgenic mice also increased the frequency of base substitution mutations that occurred at A:T base pairs when compared to air controls. The increased frequency of specific mutations at G:C base pairs in spleen was not observed in our previous studies in bone marrow and indicates tissue-specific differences in the BD-induced mutational spectrum. These data demonstrate that in vivo transgenic mouse mutagenicity assays can identify tissue-specific mutagenicity and mutational spectrum responses of genotoxic carcinogens at exposure levels that are known to induce tumors.


Assuntos
Proteínas de Bactérias/genética , Butadienos/toxicidade , Proteínas de Escherichia coli , Mutagênicos/toxicidade , Proteínas Repressoras/genética , Administração por Inalação , Animais , Proteínas de Bactérias/biossíntese , Butadienos/administração & dosagem , Elementos de DNA Transponíveis , Relação Dose-Resposta a Droga , Repressores Lac , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Testes de Mutagenicidade , Mutagênicos/administração & dosagem , Mutação Puntual , Proteínas Repressoras/biossíntese , Deleção de Sequência
7.
Mutagenesis ; 12(5): 359-64, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9379915

RESUMO

1,3-Butadiene (BD) is an indirect-acting mutagen that is bioactivated in laboratory animals to at least two mutagenic metabolites, 1,2-expoxy-3-butene (EB) and 1,2,3,4-diepoxybutane (DEB). In the present study, the cytotoxicity, mutagenicity and mutational spectrum at hprt were determined after EB-exposure of human TK6 lymphoblastoid cells (TK6 cells). EB was cytotoxic at concentrations ranging from 200 to 1000 microM x 24 h; at 400 microM x 24 h, the cell survival relative to unexposed controls was approximately 10%. Exposure of TK6 cells to EB (400 microM x 24 h) resulted in a 5-9-fold increase in the hprt mutant frequency. Molecular characterization of EB-induced hprt mutants indicated that 78% of the mutations at hprt were single base substitutions. A significant (P < 0.05) increase in A:T-->T:A transversions was observed compared with spontaneous hprt mutants isolated during these studies. All of the A:T-->T:A transversions in EB-induced mutants occurred with the A in the non-transcribed strand. These data indicate that a primary mode of genotoxicity induced by EB in human TK6 cells is the induction of single base substitutions.


Assuntos
Compostos de Epóxi/toxicidade , Mutação da Fase de Leitura , Hipoxantina Fosforribosiltransferase/genética , Mutagênicos/toxicidade , Mutação Puntual , Deleção de Sequência , Linfócitos B , Linhagem Celular , Elementos de DNA Transponíveis , Relação Dose-Resposta a Droga , Éxons , Humanos
8.
Mutat Res ; 391(3): 153-64, 1997 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-9268040

RESUMO

In the present study, the lacI mutant frequency was determined in the tissues of B6C3F1 lacI transgenic mice exposed by inhalation to ethylene oxide (EO). Groups of 15 male transgenic lacI B6C3F1 mice were exposed to either 0, 50, 100, or 200 ppm EO for 4 weeks (6 h/day, 5 days/week) and were sacrificed at 0, 2, or 8 weeks after the last EO exposure. The lacI transgene was recovered from lung, bone marrow, spleen, and germ cells for determination of the lacI mutant frequency. The tissues selected for analysis were tumor target site tissues in chronic bioassays (lung tumors and lymphomas) and germ cells. The lacI mutant frequency in lung was significantly increased at 8 weeks post exposure to 200 ppm EO (6.2 +/- 2.2 vs. 9.1 +/- 1.5. p = 0.046). In contrast, the lacI mutant frequency in spleen and bone marrow at 2 and 8 weeks was not significantly increased in mice exposed to 200 ppm EO. The lacI mutant frequencies in male germ cells for 200 ppm EO-exposed mice were not increased compared to air controls at 2 and 8 weeks post-exposure. In a spleen cell fraction two of three EO-exposed mice at the 200 ppm exposure level demonstrated an elevated lacI mutant frequency. The increased lacI mutant frequency in these animals was likely due to mutant siblings that contained background G:C --> A:T transitions at CpG sites. These results demonstrate that a 4-week inhalation exposure to EO is mutagenic in lung. However, EO did not increase the frequency of mutations recovered at the lacI transgene in other tissues examined under the conditions used in the present studies. Since the mutational spectrum for EO in other systems consists of an increased proportion of large deletions, the lack of a mutagenic response in the tissues examined is likely due to the lack of recovery of large deletions in lambda-based shuttle vector systems. These data indicate that a primary mechanism of EO-induced mutagenicity in vivo is likely through the induction of deletions, not specific point mutations.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Escherichia coli , Óxido de Etileno/administração & dosagem , Óxido de Etileno/toxicidade , Mutação , Proteínas Repressoras/genética , Administração por Inalação , Ar , Animais , Proteínas de Bactérias/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Germinativas/efeitos dos fármacos , Hipoxantina Fosforribosiltransferase/efeitos dos fármacos , Hipoxantina Fosforribosiltransferase/genética , Repressores Lac , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Testes de Mutagenicidade/métodos , Proteínas Repressoras/efeitos dos fármacos , Túbulos Seminíferos/efeitos dos fármacos , Análise de Sequência de DNA , Baço/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
9.
Mutagenesis ; 12(2): 61-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9106245

RESUMO

1,3-Butadiene (BD) is a rodent carcinogen that is bioactivated to at least two genotoxic metabolites, 1,2-epoxybutene (EB) and 1,2,3,4-diepoxybutane (DEB). The mutational spectrum for DEB at hprt in human TK6 lymphoblasts (TK6 cells) was determined and compared with the mutational spectrum from spontaneous mutants. A DEB exposure of 4 microM for 24 h resulted in an average 5-fold increase in the hprt mutant frequency. Hprt mutants for molecular analysis were isolated from TK6 cells exposed to 4 microM DEB for 24 h (51 DEB-induced mutants) and from a set of spontaneous mutants (n = 43) isolated from the same TK6 stock cell cultures. Molecular analyses of hprt mutations were done by reverse transcription-polymerase chain reaction (RT-PCR) of hprt mRNA or exon-specific genomic PCR amplification of hprt followed by DNA sequencing of PCR products. There was an increased frequency of A:T-->T:A transversions among the DEB-induced mutants compared to spontaneous mutants (9/51; 18% DEB-induced compared to 2/43; 5% in spontaneous (one-way Fisher's exact test; P < or = 0.05). DEB-induced hprt mutants also had an increased frequency of genomic deletions affecting the 5' region of hprt (7/51; 14% DEB-induced compared to 1/43; 2% in spontaneous). Therefore, DEB is a mutagenic carcinogen that can induce genotoxicity by large deletions, rearrangements or single base substitution mutations.


Assuntos
Compostos de Epóxi/toxicidade , Hipoxantina Fosforribosiltransferase/efeitos dos fármacos , Hipoxantina Fosforribosiltransferase/genética , Linfócitos/efeitos dos fármacos , Mutação , Composição de Bases , Carcinógenos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/estatística & dados numéricos , Elementos de DNA Transponíveis , Eletroforese em Gel de Ágar , Éxons , Humanos , Linfócitos/citologia , Mutagênicos/toxicidade , Reação em Cadeia da Polimerase/métodos , Splicing de RNA/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , Deleção de Sequência
10.
Environ Mol Mutagen ; 28(4): 424-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8991073

RESUMO

1,3-Butadiene (BD) is a carcinogen that is bioactivated to at least two genotoxic metabolites. In the present article, we review briefly our previous studies on the in vivo mutagenicity and mutational spectra of BD in bone marrow and extend these studies to examine the effect of exposure time (5-days vs. 4-week exposure to 625 ppm BD used in previous studies) on the lacI mutant frequency in the bone marrow. Inhalation exposure to BD at 625 ppm and 1,250 ppm mutagenic in vivo, inducing an increase in the transgene mutant and mutation frequency in the bone marrow. Analysis of the mutational spectrum in BD-exposed and air control mice demonstrated that BD exposure induced an increased frequency of mutations at A:T base pairs. There was no difference in the lacI mutant frequency determined in the bone marrow between a short-term exposure to BD (5 days) and a longer-term exposure (4 weeks). These data taken together demonstrate that inhalation exposure to BD induces in vivo somatic cell mutation.


Assuntos
Proteínas de Bactérias/genética , Medula Óssea/efeitos dos fármacos , Butadienos/toxicidade , Proteínas de Escherichia coli , Mutação/efeitos dos fármacos , Proteínas Repressoras/genética , Administração por Inalação , Animais , Proteínas de Bactérias/efeitos dos fármacos , Butadienos/administração & dosagem , Repressores Lac , Masculino , Camundongos , Camundongos Transgênicos , Testes de Mutagenicidade , Mutagênicos/toxicidade , Proteínas Repressoras/efeitos dos fármacos , Fatores de Tempo
11.
Environ Mol Mutagen ; 26(1): 1-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7641703

RESUMO

We have examined the spectra of mutations in a collection of 74 lacI mutants isolated from the bone marrow of B6C3F1 lacI transgenic mice exposed to 1,250 ppm 1,3-butadiene (BD). Of the 49 independent mutations analyzed in the present study, 30 of 49 (61%) were point mutations at G:C base pairs, and 10 of 49 (20%) were point mutations at A:T base pairs. The remaining mutations consisted of small deletions and insertions and a single tandem change. An analysis of variance (ANOVA) on the frequency of specific mutations observed in each animal in this mutagenicity experiment [present study; also Sisk SC et al. (1994): Carcinogenesis 15:471-477] indicated that the frequency of point mutations at A:T base pairs is significantly greater (P < 0.05) in BD-exposed mice than in the air controls. In addition, there was a decrease (P < 0.05; Fisher's exact test) in the frequency of G:C-->A:T transitions at 5'-CpG-3' sites in BD-exposed mice (27%) relative to air controls (51%). These data indicate that subchronic exposures to BD induces an increased frequency of in vivo mutation at A:T base pairs in the bone marrow of B6C3F1 lacI transgenic mice.


Assuntos
Proteínas de Bactérias/genética , Medula Óssea/efeitos dos fármacos , Butadienos/toxicidade , Proteínas de Escherichia coli , Mutagênese , Mutagênicos/toxicidade , Mutação Puntual , Proteínas Repressoras/genética , Deleção de Sequência , Adenina , Análise de Variância , Animais , Proteínas de Bactérias/biossíntese , Composição de Bases , Sequência de Bases , Medula Óssea/patologia , Elementos de DNA Transponíveis , Repressores Lac , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Repressoras/biossíntese , Timina
13.
Z Hautkr ; 59(11): 739-48, 1984 Jun 01.
Artigo em Alemão | MEDLINE | ID: mdl-6385512

RESUMO

In patients with re- and multiple syphilitic infections the titres of VDRL-, FTA- and SPHA-tests were compared. Among reinfections in which the VDRL gave no or initially no hint for a new infection, the SPHA is significantly reactive. The increase of IgG in the FTA-test confirmed the specificity of a new infection.


Assuntos
Hemadsorção , Sorodiagnóstico da Sífilis/métodos , Sífilis/imunologia , Anticorpos Antibacterianos/análise , Humanos , Imunoglobulina G/análise , Recidiva , Treponema pallidum/imunologia
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