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1.
Ann Oncol ; 26(8): 1754-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25969370

RESUMO

BACKGROUND: To investigate the impact of perioperative chemo(radio)therapy in advanced primary urethral carcinoma (PUC). PATIENTS AND METHODS: A series of 124 patients (86 men, 38 women) were diagnosed with and underwent surgery for PUC in 10 referral centers between 1993 and 2012. Kaplan-Meier analysis with log-rank testing was used to investigate the impact of perioperative chemo(radio)therapy on overall survival (OS). The median follow-up was 21 months (mean: 32 months; interquartile range: 5-48). RESULTS: Neoadjuvant chemotherapy (NAC), neoadjuvant chemoradiotherapy (N-CRT) plus adjuvant chemotherapy (ACH), and ACH was delivered in 12 (31%), 6 (15%) and 21 (54%) of these patients, respectively. Receipt of NAC/N-CRT was associated with clinically node-positive disease (cN+; P = 0.033) and lower utilization of cystectomy at surgery (P = 0.015). The objective response rate to NAC and N-CRT was 25% and 33%, respectively. The 3-year OS for patients with objective response to neoadjuvant treatment (complete/partial response) was 100% and 58.3% for those with stable or progressive disease (P = 0.30). Of the 26 patients staged ≥cT3 and/or cN+ disease, 16 (62%) received perioperative chemo(radio)therapy and 10 upfront surgery without perioperative chemotherapy (38%). The 3-year OS for this locally advanced subset of patients (≥cT3 and/or cN+) who received NAC (N = 5), N-CRT (N = 3), surgery-only (N = 10) and surgery plus ACH (N = 8) was 100%, 100%, 50% and 20%, respectively (P = 0.016). Among these 26 patients, receipt of neoadjuvant treatment was significantly associated with improved 3-year relapse-free survival (RFS) (P = 0.022) and OS (P = 0.022). Proximal tumor location correlated with inferior 3-year RFS and OS (P = 0.056/0.005). CONCLUSION: In this series, patients who received NAC/N-CRT for cT3 and/or cN+ PUC appeared to demonstrate improved survival compared with those who underwent upfront surgery with or without ACH.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Carcinoma de Células de Transição/terapia , Quimiorradioterapia/métodos , Quimioterapia Adjuvante/métodos , Terapia Neoadjuvante/métodos , Uretra/cirurgia , Neoplasias Uretrais/terapia , Adenocarcinoma/mortalidade , Idoso , Paclitaxel Ligado a Albumina/administração & dosagem , Carboplatina/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células de Transição/mortalidade , Cisplatino/administração & dosagem , Cistectomia , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Ifosfamida/administração & dosagem , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Paclitaxel/administração & dosagem , Assistência Perioperatória , Estudos Retrospectivos , Neoplasias Uretrais/mortalidade , Derivação Urinária , Gencitabina
2.
Int J Pharm ; 337(1-2): 239-45, 2007 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-17317048

RESUMO

The extrusion/spheronisation technique has made a notable contribution to the existing range of pharmaceutical forms especially in the area of modified-release products. The twin product/process approach adopted in this work is based on the on-line monitoring of the hydro-textural characteristics of the product up to its final form. The objective is to balance the influence of the operating parameters for each successive stage against the influence of product characteristics. A coherent "representational framework" is proposed for insoluble substances through a diagram locating intergranular porosity value depending on water content. The wetting/kneading operation brings the material to a state in which porosity is linked to water content. The extrusion operation densifies the material to saturation point, while spheronisation is only a shaping process which maintains hydro-textural state. The drying operation finalises the textural characteristics of the product by densifying the medium through induced shrinkage.


Assuntos
Celulose/química , Excipientes/química , Ibuprofeno/química , Tecnologia Farmacêutica/métodos , Química Farmacêutica , Dessecação , Formas de Dosagem , Composição de Medicamentos , Modelos Químicos , Porosidade , Reprodutibilidade dos Testes , Solubilidade , Água/química
3.
Cell Mol Life Sci ; 59(3): 540-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11964131

RESUMO

The carnitine system plays a key role in beta-oxidation of long-chain fatty acids by permitting their transport into the mitochondrial matrix. The effects of hypothyroidism and hyperthyroidism were studied on gamma-butyrobetaine hydroxylase (BBH), the enzyme responsible for carnitine biosynthesis in the rat. In rat liver, BBH activity was decreased in the hypothyroid state and increased in hyperthyroid animals. The modifications in BBH activity correlated with changes in the enzyme Vmax values. These changes were shown to be related to hepatic BBH mRNA abundance. Thyroid hormones are known to interact with lipid metabolism, in particular by increasing long-chain fatty acid oxidation through activation of carnitine-dependent fatty acid import into mitochondria. Our study showed that thyroid hormones also increased carnitine bioavailability.


Assuntos
Carnitina/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Oxigenases de Função Mista/metabolismo , Hormônios Tireóideos/farmacologia , Animais , Cinética , Fígado/enzimologia , Masculino , Oxigenases de Função Mista/biossíntese , Oxigenases de Função Mista/genética , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , gama-Butirobetaína Dioxigenase
4.
Biochem Pharmacol ; 59(11): 1357-63, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10751544

RESUMO

Carnitine is involved in the transfer of fatty acids across mitochondrial membranes. Carnitine is found in dairy and meat products, but is also biosynthesized from lysine and methionine via a process that, in rat, takes place essentially in the liver. After intestinal absorption or hepatic biosynthesis, carnitine is transferred to organs whose metabolism is dependent on fatty acid oxidation, such as heart and skeletal muscle. In skeletal muscle, carnitine concentration was found to be 50 times higher than in the plasma, implicating an active transport system for carnitine. In this study, we characterized this transport in isolated rat myotubes, established mouse C2C12 myoblastic cells, and rat myotube plasma membranes and found that it was Na(+)-dependent and partly inhibited by a Na(+)/K(+) ATPase inhibitor. L-carnitine analogues such as D-carnitine and gamma-butyrobetaine interfere with this system as does acyl carnitine. Among these inhibitors, the most potent was mildronate (3-(2,2,2-trimethylhydrazinium)propionate), known as a gamma-butyrobetaine hydroxylase inhibitor. It also induced a marked decrease in carnitine transport into muscle cells. Removal of carnitine or treatment with mildronate induced growth inhibition of cultured C2C12 myoblastic cells. These data suggest that myoblast growth and/or differentiation is dependent upon the presence of carnitine.


Assuntos
Carnitina/metabolismo , Metilidrazinas/farmacologia , Músculo Esquelético/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Técnicas In Vitro , Masculino , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Wistar
5.
Biochim Biophys Acta ; 1441(1): 85-92, 1999 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-10526231

RESUMO

Carnitine biosynthesis from lysine and methionine involves five enzymatic reactions. gamma-butyrobetaine hydroxylase (BBH; EC 1.14. 11.1) is the last enzyme of this pathway. It catalyzes the reaction of hydroxylation of gamma-butyrobetaine to carnitine. The cDNA encoding this enzyme has been isolated and characterized. The cDNA contained an open reading frame of 1161 bp encoding a protein of 387 amino acids with a deduced molecular weight of 44.5 kDa. The sequence of the cDNA showed an important homology with the human cDNA recently isolated. Northern analysis showed gamma-butyrobetaine hydroxylase expression in the liver and in some extend in the testis and the epididymis. During this study, it also appeared that BBH mRNA expression was undetectable by Northern analysis during the perinatal period. During the development of the rat, the amount of BBH mRNA appeared after the weaning of the young rat and reached a maximal expression at the adult stage.


Assuntos
Fígado/enzimologia , Oxigenases de Função Mista/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/química , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Oxigenases de Função Mista/química , Dados de Sequência Molecular , Ratos , Ratos Wistar , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , gama-Butirobetaína Dioxigenase
6.
Mol Cell Biochem ; 178(1-2): 163-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9546596

RESUMO

The biosynthesis of carnitine from lysine and methionine involves five enzymatic reactions. Gamma-butyrobetaine hydroxylase (BBH; EC 1.14.11.1) is the last enzyme of this pathway. It catalyzes the reaction of hydroxylation of gamma-butyrobetaine to carnitine. This enzyme had never been purified to homogeneity from rat tissue. This paper describes the purification and characterization of the rat liver BBH. This protein has been purified some 413 fold by ion exchange, affinity and gel-filtration chromatographies and appears as a dimere of 43,000 Daltons subunits by PAGE. The affinity chromatography column used in the purification process utilizes 3-(2,2,2-trimethylhydrazinium)propionate (THP), a BBH inhibitor, as the ligand. Polyclonal antibodies were raised against the liver enzyme. They were able to precipitate BBH activity in either a crude liver extract or a purified fraction of the enzyme. Furthermore, it crossreacts with a 43 kDa protein in the liver. No evidence for extra hepatic enzyme was found.


Assuntos
Carnitina , Fígado/enzimologia , Oxigenases de Função Mista/isolamento & purificação , Animais , Ácido Ascórbico/farmacologia , Betaína/análogos & derivados , Betaína/metabolismo , Catalase/metabolismo , Catálise , Cromatografia de Afinidade , Inibidores Enzimáticos/metabolismo , Compostos Ferrosos/farmacologia , Hidroxilação , Ácidos Cetoglutáricos/metabolismo , Cinética , Ligantes , Masculino , Metilidrazinas/metabolismo , Peso Molecular , Ratos , Ratos Wistar , gama-Butirobetaína Dioxigenase
8.
Blood ; 76(10): 1965-71, 1990 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2122918

RESUMO

This study reports the detection of an activity that stimulates the development of a subclass of burst-forming unit-erythroid (BFU-E) progenitors giving rise to small bursts in semi-solid cultures established in the presence of saturating concentrations of erythropoietin. These progenitors are considered to be mature BFU-E. The activity is found in extracts from kidney cells and appears to be physiologically regulated as it was respectively enhanced and decreased in kidneys from anemic and polycythemic mice. The disappearance of activity in kidney-cell extracts during long-term polycythemia correlated with an accumulation of mature BFU-E in the spleen and bone marrow of polycythemic mice. Using specific neutralizing antibodies and in vitro tests, we also show that this activity is different from hemopoietins known to share burst promoting activity (Interleukin-3 [IL-3], granulocyte-macrophage colony-stimulating factor [GM-CSF], Interleukin-4 [IL-4], erythropoietin [EPO], human interleukin for DA cells [HILDA]) and that it can stimulate erythroid differentiation in long term bone marrow cell cultures.


Assuntos
Extratos Celulares/farmacologia , Células Precursoras Eritroides/citologia , Eritropoese/efeitos dos fármacos , Inibidores do Crescimento , Interleucina-6 , Rim/citologia , Animais , Medula Óssea/efeitos dos fármacos , Células da Medula Óssea , Divisão Celular/efeitos dos fármacos , Extratos Celulares/análise , Células Cultivadas , Células Precursoras Eritroides/efeitos dos fármacos , Eritropoetina/análise , Eritropoetina/farmacologia , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/análise , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Interleucina-3/análise , Interleucina-3/farmacologia , Interleucina-4/análise , Interleucina-4/farmacologia , Rim/química , Rim/fisiologia , Fator Inibidor de Leucemia , Linfocinas/análise , Linfocinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
Food Addit Contam ; 7 Suppl 1: S162-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2262028

RESUMO

Liver nuclei, prepared from normal and vitamin A-deficient rats, were incubated in the presence of GDP-(14C)mannose or UDP-N-acetyl(14C)glucosamine and the labelled glycoproteins analysed by SDS PAGE. Fluorographic analysis has shown that (14C) mannose labelling is enhanced by vitamin A deficiency whereas N-acetyl(14C)glucosamine transfer remains approximately at the same level regardless of the vitamin A status; we did not notice any modification when the proteins were monitored by Coomassie blue or by silver nitrate.


Assuntos
Acetilglucosamina/metabolismo , Fígado/metabolismo , Manose/metabolismo , Deficiência de Vitamina A/metabolismo , Animais , Peso Corporal , Dieta , Eletroforese em Gel de Poliacrilamida , Glicoproteínas/análise , Glicosilação , Fígado/enzimologia , Ratos , Ratos Endogâmicos , Vitamina A/administração & dosagem
10.
Biochem Int ; 17(1): 59-67, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2973320

RESUMO

The transfer of N-acetyl(14C)glucosamine from UDP-N-acetyl(14C)glucosamine to endogenous glycoproteins acceptors were studied comparatively in the nuclei and in the non-nuclear membranes of rat hepatocytes. Electrophoretic and autoradiographic analysis show that most of the glycoprotein acceptors of the nuclei differ from those of the non-nuclear membranes in terms of molecular weight. In addition, it may interesting to mention that in the nuclear fraction a 30% inhibition by tunicamycin is obtained for concentrations as low as 0.03 microM, whereas at this concentration no effect is detected in the non-nuclear membranes. In the presence of 0.2 microM tunicamycin, the inhibition does not go beyond 25% in the latter fraction but goes up to 80% in the former. The previous results demonstrate clearly that a particular glycosylation reaction occurs in the nucleus.


Assuntos
Acetilglucosamina/metabolismo , Núcleo Celular/metabolismo , Glucosamina/análogos & derivados , Glicoproteínas/metabolismo , Membranas Intracelulares/metabolismo , Fígado/metabolismo , N-Acetilglucosaminiltransferases , Animais , Autorradiografia , Transporte Biológico , Eletroforese em Gel de Poliacrilamida , Glucosiltransferases/metabolismo , Ratos , Ratos Endogâmicos , Tunicamicina/farmacologia
11.
Biochem Int ; 16(3): 429-38, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2454621

RESUMO

Nuclei and non-nuclear membranes were tested for their ability to transfer in vitro (14C)mannose from GDP-(14C)mannose to endogenous glycoprotein acceptors in the presence and in the absence of exogenous retinyl-phosphate. Electrophoretic analysis shows that retinylphosphate is responsible for the labeling of a few endogenous acceptors only in the non-nuclear membranes; in the nuclei the mannosylation reaction is not retinylphosphate dependent and the electrophoretic profile of the labeled protein acceptors is different from that of the non-nuclear membranes.


Assuntos
Glicoproteínas/biossíntese , Guanosina Difosfato Manose/metabolismo , Fígado/metabolismo , Manose/metabolismo , Glicoproteínas de Membrana/biossíntese , Proteínas Nucleares/biossíntese , Açúcares de Nucleosídeo Difosfato/metabolismo , Animais , Autorradiografia , Radioisótopos de Carbono , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Diterpenos , Masculino , Microscopia Eletrônica , Monossacarídeos de Poli-Isoprenil Fosfato/metabolismo , Ratos , Ratos Endogâmicos
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