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1.
Ann Oncol ; 24(6): 1645-52, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23436910

RESUMO

BACKGROUND: Maintenance acupuncture is advocated by clinicians after successful clinic-based acupuncture. We aimed to assess the effectiveness of maintenance acupuncture in the management of cancer-related fatigue (CRF); treatment delivered by therapists or self-acupuncture/self-needling was compared with no maintenance treatment. METHODS: Breast cancer patients who participated in a randomized trial of acupuncture for CRF management (reported elsewhere) were re-randomized to receive an additional four acupuncturist-delivered weekly sessions; four self-administered weekly acupuncture sessions (self-needling); or no acupuncture. Primary outcome was general fatigue (Multidimensional Fatigue Inventory). Mood, quality of life and safety were also assessed. RESULTS: In total, 197 patients were re-randomized, with 65 to therapist-delivered sessions, 67 to self-acupuncture/self-needling and 65 to no further acupuncture. Primary outcome scores were equivalent between the therapist-delivered acupuncture and self-acupuncture (P > 0.05). A non-significant trend in improving fatigue was observed at the end of 4 weeks in the combined acupuncture arms (P = 0.07). There was no impact on mood or quality of life of the further acupuncture sessions at 18 weeks beyond the improvement observed in initial trial. CONCLUSION: Self-acupuncture is an acceptable, feasible and safe maintenance treatment for patients with CRF. However, overall, maintenance acupuncture did not yield important improvements beyond those observed after an initial clinic-based course of acupuncture. TRIAL REGISTRATION NUMBER: NCT00957112.


Assuntos
Terapia por Acupuntura/métodos , Fadiga/terapia , Pessoal de Saúde , Agulhas , Neoplasias/terapia , Autocuidado/métodos , Terapia por Acupuntura/normas , Fadiga/epidemiologia , Feminino , Pessoal de Saúde/normas , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas/normas , Neoplasias/epidemiologia , Autocuidado/normas , Resultado do Tratamento
4.
Toxicol Sci ; 56(1): 26-36, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10869451

RESUMO

Mice are resistant to the carcinogenic effects of the mycotoxin aflatoxin B(1) (AFB(1)) because they constitutively express an alpha-class glutathione S-transferase (mGSTA3-3) that has high (approximately 200,000 pmol/min/mg) activity toward aflatoxin B(1)-8, 9-epoxide (AFBO). Rats do not constitutively express a GST with high AFBO-conjugating activity and are sensitive to AFB(1)-induced hepatocarcinogenesis. Constitutively expressed human hepatic alpha-class GSTs (hGSTA1-1 and hGSTA2-2) possess little or no AFBO-detoxifying activity (<2 pmol/min/mg). Recently, we found that the nonhuman primate, Macaca fascicularis (Mf), exhibits significant (approximately 300 pmol/min/mg) constitutive hepatic GST activity towards AFBO. To determine which specific GST isoenzyme(s) is (are) responsible for this activity, MF: GSTs were purified from liver tissue and characterized and, Mf mu-class GST cDNAs were cloned by reverse transcriptase-coupled polymerase chain reaction (RT-PCR). Purification by glutathione agarose (GSHA) affinity chromatography yielded a protein, GSHA-GST, that exhibited relatively high AFBO-conjugating activity (239 pmol/min/mg) compared to other GST-containing peaks. Western blotting and enzymatic activity analyses revealed that GSHA-GST belongs to the mu class. Two distinct mu-class GST cDNAs, mfaGSTM1 (GenBank accession # AF200709) and mfaGSTM2 (GenBank accession # AF200710), were generated by RT-PCR. CDNA-derived amino acid sequence analysis revealed that mfaGSTM1 and mfaGSTM2 share 97% and 96% homology with the human mu-class GSTs hGSTM4 and hGSTM2, respectively. In contrast to recombinant mfaGSTM1-1, which had no detectable AFBO-conjugating activity, mfaGSTM2-2 exhibited this activity at 333 pmol/min/mg. Activity profiles for the stereoisomers exo- and endo-AFBO, and of 1-chloro-2,4-dinitrobenzene of the purified protein GSHA-GST and recombinant mfaGSTM2-2, suggested that they are two distinct enzymes. Our results indicate that, in contrast to rodents, mu-class GSTs are responsible for the majority of AFBO-conjugating activity in the liver of Macaca fascicularis.


Assuntos
Aflatoxina B1/análogos & derivados , Carcinógenos/metabolismo , Sulfatos de Condroitina/metabolismo , Dissacarídeos/metabolismo , Fígado/enzimologia , Macaca fascicularis , Aflatoxina B1/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Sulfatos de Condroitina/classificação , Sulfatos de Condroitina/genética , Sulfatos de Condroitina/isolamento & purificação , Cromatografia de Afinidade , Clonagem Molecular , DNA Complementar/metabolismo , Dissacarídeos/classificação , Dissacarídeos/genética , Dissacarídeos/isolamento & purificação , Masculino , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
Stem Cells ; 16(6): 375-86, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9831863

RESUMO

Radiation-induced pancytopenia proved to be a suitable model system in mice and rhesus monkeys for studying thrombopoietin (TPO) target cell range and efficacy. TPO was highly effective in rhesus monkeys exposed to the mid-lethal dose of 5 Gy (300 kV x-rays) TBI, a model in which it alleviated thrombocytopenia, promoted red cell reconstitution, accelerated reconstitution of immature CD34+ bone marrow cells, and potentiated the response to growth factors such as GM-CSF and G-CSF. In contrast to the results in the 5 Gy TBI model, TPO was ineffective following transplantation of limited numbers of autologous bone marrow or highly purified stem cells in monkeys conditioned with 8 Gy TBI. In the 5 Gy model, a single dose of TPO augmented by GM-CSF 24 h after TBI was effective in preventing thrombocytopenia. The strong erythropoietic stimulation may result in iron depletion, and TPO treatment should be accompanied by monitoring of iron status. This preclinical evaluation thus identified TPO as a potential major therapeutic agent for counteracting radiation-induced pancytopenia and demonstrated pronounced stimulatory effects on the reconstitution of immature CD34+ hemopoietic cells with multilineage potential. The latter observation explains the potentiation of the hematopoietic responses to G-CSF and GM-CSF when administered concomitantly. It also predicts the effective use of TPO to accelerate reconstitution of immature hematopoietic cells as well as possible synergistic effects in vivo with various other growth factors acting on immature stem cells and their direct lineage-committed progeny. The finding that a single dose of TPO might be sufficient for a clinically significant response emphasizes its potency and is of practical relevance. The heterogeneity of the TPO response encountered in the various models used for evaluation points to multiple mechanisms operating on the TPO response and heterogeneity of its target cells. Mechanistic mouse studies made apparent that the response of multilineage cells shortly after TBI to a single administration of TPO is quantitatively more important for optimal efficacy than the lineage-restricted response obtained at later intervals after TBI and emphasized the importance of a relatively high dose of TPO to overcome initial c-mpl-mediated clearance. Further elucidation of mechanisms determining efficacy might very well result in a further improvement, e.g., following transplantation of limited numbers of stem cells. Adverse effects of TPO administration to myelosuppressed or stem cell transplanted experimental animals were not observed.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Trombocitopenia/prevenção & controle , Trombopoetina/farmacologia , Animais , Modelos Animais de Doenças , Humanos , Imunidade/efeitos da radiação , Camundongos , Primatas , Proteínas Recombinantes/farmacologia , Trombocitopenia/tratamento farmacológico , Trombocitopenia/etiologia
6.
Cancer Res ; 54(17): 4573-5, 1994 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8062243

RESUMO

Mice are resistant to aflatoxin carcinogenicity primarily due to expression of a glutathione S-transferase (mYc) with high catalytic activity toward aflatoxin B1-8,9-epoxide (AFBO). In contrast, rats are more sensitive to aflatoxin carcinogenicity due to the constitutive expression of a glutathione S-transferase with relatively low catalytic activity toward AFBO (rYc1). To identify the contribution of different regions of the mYc protein that confer high catalytic activity toward AFBO, six chimeric mYc/rYc1 GST enzymes were generated utilizing full and partial restriction enzyme digestions at two conserved StyI sites in the mYc and rYc1 complementary DNAs (between amino acid residues 56-57 and 142-143). Recombinant wild-type and chimeric glutathione S-transferases were bacterially expressed, affinity purified, and their catalytic activities measured toward AFBO, delta 5-androstene-3,17-dione, 1-chloro-2,4-dinitrobenzene, and ethacrynic acid. The set of chimeras displayed a wide range of catalytic activities toward the substrates assayed. The chimeras with the greatest activity toward AFBO were 1:56rat-57: 221mouse and 1:56mouse-57:142rat-143:221mouse, with AFBO conjugating activities 200 and 8 times greater than wild-type rYc1, respectively. These results demonstrate that the residues that confer high AFBO conjugation activity in mYc are located in the region spanning residues 57-221.


Assuntos
Aflatoxina B1/metabolismo , Dinitroclorobenzeno/metabolismo , Glutationa Transferase/química , Proteínas Recombinantes de Fusão/química , Sequência de Aminoácidos , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Ácido Etacrínico/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Relação Estrutura-Atividade
7.
Toxicol Appl Pharmacol ; 123(2): 257-64, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7902618

RESUMO

1-Cyano-2-hydroxy-3-butene (CHB), an aliphatic nitrile found in cruciferous vegetables, causes a two- and sevenfold elevation in reduced glutathione (GSH) in rat liver and pancreas, respectively, after oral administration of 200 mg/kg. While this dose is also associated with pancreatotoxicity, a single 100 mg/kg dose or multiple lesser doses show the same effect, although somewhat reduced in magnitude, with no concomitant toxicity. In an attempt to identify the mechanism of this increase, we investigated the effect of CHB on GSH synthesis by examining the effect of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, on CHB-induced GSH elevation. Male Fischer 344 rats received 3 mmol BSO/kg ip 24 and 34 hr following CHB or corn oil. The CHB-mediated elevation in hepatic and pancreatic GSH was eradicated by BSO, suggesting that increased synthesis was responsible. The rate-limiting step in synthesis is gamma-glutamyl cysteine synthetase (GCS); the limiting substrate is cysteine. Therefore, CHB effects on GCS activity and hepatic and pancreatic cysteine equivalents were investigated. When rats were treated by gavage with CHB (100 mg/kg), hepatic GCS mRNA concentrations were increased 24 hr after treatment and hepatic cysteine equivalents were significantly elevated 4 hr following CHB. No significant elevation in hepatic GCS activity was observed, however, even 24 hr following CHB. Pancreatic cysteine equivalents were elevated at both 4 and 8 hr after CHB treatment. However, there was no detectable GCS mRNA or activity in pancreas, in either control or treated animals. Furthermore, CHB had no direct effect on the activity of GCS purified from kidney, regardless of whether GSH was present or absent. These results suggest that the mechanism of CHB-mediated induction of GSH may involve early increases in GSH precursors as well as a later increase in GCS mRNA. The mechanism of GSH elevation identified in these studies may hold therapeutic or prophylactic implications.


Assuntos
Alcenos/farmacologia , Glutationa/biossíntese , Fígado/efeitos dos fármacos , Nitrilas/farmacologia , Pâncreas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Sequência de Bases , Butionina Sulfoximina , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Fígado/metabolismo , Masculino , Metionina Sulfoximina/análogos & derivados , Metionina Sulfoximina/farmacologia , Dados de Sequência Molecular , Pâncreas/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , gama-Glutamiltransferase/metabolismo
8.
Ophthalmic Res ; 18(6): 357-62, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3299199

RESUMO

Since increased lens sorbitol and osmotic swelling are central causative features of cataract in diabetic rats, the effects of insulin treatment on lens sorbitol, water, sodium, and potassium were studied. The sorbitol concentration in early stage diabetic lenses was greater than in normal ones by 83 mmol/kg water, and the lens water was greater by 1.3%. Sodium was greater by 9 mmol/kg water; potassium was less by the same amount so that the sum of sodium and potassium was not different. In insulin-treated diabetic lenses, the sorbitol was less than in untreated diabetic lenses by 39 mmol/kg water, and the lens water was not different. Insulin restored the potassium, but not the sodium, to normal concentration so that the sum of sodium and potassium was greater by 16 mmol/kg water. The differences in lens water were less than would be expected on the basis of osmosis due to differences in sorbitol and suggested that the lenses were able to maintain their water content within a narrow range by losing or gaining solutes to offset the differences in sorbitol.


Assuntos
Água Corporal/metabolismo , Diabetes Mellitus Experimental/metabolismo , Insulina/uso terapêutico , Cristalino/metabolismo , Sorbitol/metabolismo , Aloxano , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Concentração Osmolar , Potássio/metabolismo , Ratos , Ratos Endogâmicos , Sódio/metabolismo
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