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1.
J Bus Ethics ; : 1-36, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36643015

RESUMO

Deontological and teleological evaluations are widely utilized in the context of consumer decision-making. Despite their use, the differential effect of these distinct types of evaluations, and the conditions under which they hold, remains an unresolved issue. Thus, we conduct a meta-analysis of 316 effect sizes, from 53 research articles, to evaluate the extent to which deontological and teleological evaluations influence ethical judgments and intentions, and under what circumstances the influence occurs. The effect is explored across three categories of moderators: (1) contextual elements of the ethical issue, (2) stakeholders, and (3) methodological characteristics of primary studies. We find that the overall effect of deontological evaluations on ethical judgments and intentions is stronger than for teleological evaluations; however, the magnitude of the effect is contingent on several moderators. Deontological evaluations are weaker in offline consumer contexts and stronger when there are financial implications of the ethical issue. Conversely, the effect of teleological evaluations is relatively stable across ethical consumer contexts. Teleological evaluations are stronger from a utilitarian perspective than from an egoist one. Furthermore, the effect of deontological evaluations is weaker, but the effect for teleological evaluations is stronger, when the decision-maker has a personal relationship (as compared to an organizational relationship) with the victim of the unethical act. Findings validate the effect of both deontological and teleological evaluations on ethical judgments and intentions and highlight their importance in consumers' ethical decision-making. Implications for developing programs to prevent consumer unethical behavior are discussed.

2.
J Nat Prod ; 64(11): 1460-2, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11720534

RESUMO

An investigation on the gum exudates of Commiphora myrrha has led to the isolation of six sesquiterpenoids. On the basis of spectroscopic data interpretation, they were determined as two new furanosesquiterpenoids, rel-1S,2S-epoxy-4R-furanogermacr-10(15)-en-6-one (1) and rel-2R-methyl-5S-acetoxy-4R-furanogermacr-1(10)Z-en-6-one (2), and four known furanosesquiterpenoids, rel-3R-methoxy-4S-furanogermacra-1E,10(15)-dien-6-one (3), rel-2R-methoxy-4R-furanogermacr-1(10)E-en-6-one (4), furanogermacra-1(10)Z,4Z-dien-6-one, and curzerenone [6,7-dihydro-5beta-isopropenyl-3,6beta-dimethyl-6-vinylbenzofuran-4(5H)-one]. This is the first report of the relative stereochemistry for the known compounds 3 and 4. Compound 1 exhibited weak cytotoxic activity against a MCF-7 breast tumor cell line in a clonogenic assay, while the other five compounds were inactive in this assay.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Burseraceae/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Sesquiterpenos de Germacrano , Sesquiterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama , Cromatografia em Camada Fina , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plantas Medicinais/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
3.
Hematol Oncol Clin North Am ; 15(3): 509-24, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11525294

RESUMO

The understanding of apoptotic pathways provides new insights into cancer therapy. Therapies that modulate these pathways may induce apoptosis or sensitize tumor cells to other agents. Because many of the components of these pathways are altered in tumor cells compared with normal cells, therapies that target these abnormal apoptotic proteins may be more selective than traditional cytotoxic agents. Difficulties include the translation of the knowledge of these pathways into clinical trials and monitoring the predicted biologic effects in patients. The continued study of new targets, agents capable of modulating these targets, and markers of biologic effect in patients should improve clinical results.


Assuntos
Adenocarcinoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Proteínas Serina-Treonina Quinases , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Caspases/fisiologia , Cisteína Endopeptidases , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/uso terapêutico , Progressão da Doença , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Proteína Ligante Fas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes bcl-2 , Genes p53 , Humanos , Interferons/uso terapêutico , Masculino , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Knockout , Mitocôndrias/fisiologia , Complexos Multienzimáticos/antagonistas & inibidores , NF-kappa B/fisiologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Oligonucleotídeos Antissenso/uso terapêutico , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Projetos Piloto , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Complexo de Endopeptidases do Proteassoma , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Retinoides/uso terapêutico , Proteína Supressora de Tumor p53/fisiologia
4.
Phytochemistry ; 56(7): 723-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11314959

RESUMO

Bioactivity-directed fractionation and purification afforded cytotoxic components of Commiphora wightii. The exudates of C. wightii were extracted with EtOAc and the extract was subjected to repeated column chromatography. A fraction showing cytotoxic activity was characterized as a mixture of two ferulates with an unusual skeleton by spectral and chemical methods, including by NMR, GC-MS and chemical derivatization. This fraction also showed moderate scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.


Assuntos
Antineoplásicos Fitogênicos/química , Sobrevivência Celular/efeitos dos fármacos , Extratos Vegetais/química , Rosales/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Neoplasias da Mama , Commiphora , Feminino , Sequestradores de Radicais Livres/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Masculino , Gomas Vegetais , Neoplasias da Próstata , Células Tumorais Cultivadas
5.
Anticancer Res ; 20(4): 2653-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10953339

RESUMO

Herbal therapies are commonly used by patients with cancer, despite little understanding about their clinical and biological activity. We recently demonstrated that the herbal combination PC-SPES, which contains licorice root, had potent estrogenic activity in vitro, in animals, and in patients with prostate cancer. Licochalcone-A (LA) is one flavonoid extracted from licorice root with antiparasitic and anti-tumor activity, but the effect on the human estrogen receptor and mechanism of anti-tumor activity is unknown. Recent studies demonstrated that the mechanism of cytotoxic effect by some estrogens may involve modulation of the anti-apoptotic protein bcl-2. In the present study, we determined if LA had estrogenic activity, anti-tumor activity, and modulated the apoptotic protein bcl-2 in human cell lines derived from acute leukemia, breast cancer, and prostate cancer. A yeast growth-based assay under the control of the human estrogen receptor (hER) demonstrated that LA was a phytoestrogen. A cell viability assay demonstrated that LA had anti-tumor activity in all cell lines tested and enhanced the effect of paclitaxel and vinblastine chemotherapy. LA induced apoptosis in MCF-7 and HL-60 cell lines, as demonstrated by cleavage of PARP, the substrate of ICE-like proteases. Immunoblot analysis demonstrated that LA decreased the anti-apoptotic protein bcl-2 and altered the bcl-2/bax ratio in favor of apoptosis. In contrast, the parent compound chalcone or estradiol did not decrease bc1-2 expression. Therefore, these data demonstrate that LA is a phytoestrogen with anti-tumor activity and is capable of modulating bcl-2 protein expression. The modulation of bcl-2 may be dependent on specific structural differences between LA and the parent compound chalcone and independent of LA estrogenicity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Chalcona/análogos & derivados , Estrogênios não Esteroides/farmacologia , Isoflavonas , Proteínas Proto-Oncogênicas c-bcl-2/análise , Apoptose/efeitos dos fármacos , Chalcona/farmacologia , Chalconas , Humanos , Fitoestrógenos , Preparações de Plantas , Proteínas Proto-Oncogênicas/análise , Células Tumorais Cultivadas , Leveduras/efeitos dos fármacos , Proteína X Associada a bcl-2
6.
J Clin Oncol ; 17(7): 2213-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10561278

RESUMO

PURPOSE: Recent studies demonstrate that retinoids decrease expression of the anti-apoptotic protein bcl-2, enhance the effect of chemotherapy, and act synergistically with interferon alfa (IFNalpha) to inhibit tumor cell growth in vitro. A phase I trial of 13-cis-retinoic acid (CRA), IFNalpha, and paclitaxel (TAX) was conducted to determine the toxicity and recommended phase II dose of this combination. Pharmacodynamic studies were performed to determine whether CRA and IFNalpha could modulate bcl-2 expression in vitro and in patients. PATIENTS AND METHODS: Twenty-two patients with prostate cancer or other advanced malignancies were treated with CRA/IFNalpha and escalating doses of TAX. The effect of CRA/IFNalpha on TAX pharmacokinetics was analyzed in both patients and human liver microsomes. The effect of CRA/IFNalpha on bcl-2 expression was assessed in vitro and in peripheral-blood mononuclear cells (PBMCs) by immunoblotting. RESULTS: CRA 1 mg/kg on days 1 to 4, IFNalpha 6 MU/m(2) subcutaneously on days 1 to 4, and TAX 175 mg/m(2) on day 3 was well tolerated. Pharmacokinetic studies demonstrated that CRA/IFNalpha caused a 33% decrease in TAX clearance and a 23% decrease in the area under the concentration-time curve values of the TAX metabolite 6-alfa-hydroxytaxol (6-HT). CRA alone reduced conversion of TAX to 6-HT by 41% in human liver microsomes. CRA/IFNalpha decreased bcl-2 expression in vitro and in PBMCs. CONCLUSION: CRA/IFNalpha and TAX is a well-tolerated regimen. CRA/IFNalpha increases TAX area under the concentration-time curve through an inhibitory effect of CRA on the metabolism of TAX to 6-HT. CRA/IFNalpha can modulate bcl-2 expression in vitro and demonstrates similar biologic activity in patients. Further studies will determine the activity of CRA/IFNalpha/TAX and validate the assessment of bcl-2 in PBMCs as a marker of tumor response.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacologia , Isotretinoína/administração & dosagem , Isotretinoína/farmacologia , Leucócitos Mononucleares , Fígado/efeitos dos fármacos , Masculino , Microssomos/efeitos dos fármacos , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Células Tumorais Cultivadas
7.
N Engl J Med ; 339(12): 785-91, 1998 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-9738085

RESUMO

BACKGROUND: Herbal mixtures are popular alternatives to demonstrated therapies. PC-SPES, a commercially available combination of eight herbs, is used as a nonestrogenic treatment for cancer of the prostate. Since other herbal medicines have estrogenic effects in vitro, we tested the estrogenic activity of PC-SPES in yeast and mice and in men with prostate cancer. METHODS: We measured the estrogenic activity of PC-SPES with transcriptional-activation assays in yeast and a biologic assay in mice. We assessed the clinical activity of PC-SPES in eight patients with hormone-sensitive prostate cancer by measuring serum prostate-specific antigen and testosterone concentrations during and after treatment. RESULTS: In complementary yeast assays, a 1:200 dilution of an ethanol extract of PC-SPES had estrogenic activity similar to that of 1 nM estradiol, and in ovariectomized CD-1 mice, the herbal mixture increased uterine weights substantially. In six of six men with prostate cancer, PC-SPES decreased serum testosterone concentrations (P<0.05), and in eight of eight patients it decreased serum concentrations of prostate-specific antigen. All eight patients had breast tenderness and loss of libido, and one had venous thrombosis. High-performance liquid chromatography, gas chromatography, and mass spectrometry showed that PC-SPES contains estrogenic organic compounds that are distinct from diethylstilbestrol, estrone, and estradiol. CONCLUSIONS: PC-SPES has potent estrogenic activity. The use of this unregulated mixture of herbs may confound the results of standard or experimental therapies and may produce clinically significant adverse effects.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Receptores de Estrogênio/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/química , Mama/efeitos dos fármacos , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/química , Feminino , Humanos , Libido/efeitos dos fármacos , Masculino , Camundongos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/fisiopatologia , Saccharomyces cerevisiae/efeitos dos fármacos , Testosterona/sangue , Tromboflebite/induzido quimicamente , Útero/efeitos dos fármacos , Leveduras/efeitos dos fármacos
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