RESUMO
BACKGROUND: This phase II trial compared docetaxel-cisplatin (DC) with vinorelbine-cisplatin (VC), both as first-line therapy followed by cross-over at progression to single-agent vinorelbine or docetaxel in advanced non-small-cell lung cancer (NSCLC). METHODS: Overall, 115 patients received DC (docetaxel 75 mg/m(2) and cisplatin 100 mg/m(2) both on day 1, every 3 weeks, arm A1) and 118 VC (vinorelbine 30 mg/m(2)/week on days 1 and 8 and cisplatin 100 mg/m(2) on day 1, every 3 weeks, arm B1) for six cycles, and subsequently maintained by monotherapy with docetaxel (A1) or vinorelbine (B1) with cross-over on disease progression to vinorelbine 30 mg/m(2) days 1 and 8 (A2), or docetaxel 100 mg/m(2), day 1, both every 3 weeks (B2). The primary end point was overall response rate (ORR). RESULTS: Patient characteristics were balanced; median follow-up was 8.8 months. First-line response rate was 33.9% with DC and 26.3% with VC (P=0.20). In arms A1 and B1, respectively: duration of response was similar (8.2 versus 8.4 months); median time to progression was 5 months in both; median survival was 8 versus 9 months (P=0.38); 1-, 2- and 3-year survival was 36% versus 35%, 17% versus 10% and 13% versus 6% (P not significant). However, with a low number of long-term survivors, statistical significance was not reached. Overall, almost half of the patients crossed over to second-line therapy; there were no response with vinorelbine and 6 (11.2%) partial responses with docetaxel. Considering the safety profile, the occurrence of febrile neutropenia was 9.6% with DC and 26.3% with VC. Treatment-related mortality was 2.5% with DC and 8.5% with VC. CONCLUSIONS: The trend in favour of the DC arm in ORR, even though statistical significance was not reached, is consistent with previous reports. This study suggests an activity of first-line DC in advanced NSCLC, and that second-line vinorelbine does not provide additional clinical benefit. As already shown in other studies, the use of DC in first-line should provide a better percentage of long-term survivors, despite the absence of efficacy of the second-line in our study.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Taxoides/uso terapêutico , Vimblastina/análogos & derivados , Vimblastina/uso terapêutico , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/administração & dosagem , Estudos Cross-Over , Progressão da Doença , Docetaxel , Feminino , Humanos , Infusões Intravenosas , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Análise de Sobrevida , Taxoides/administração & dosagem , Vimblastina/administração & dosagem , VinorelbinaRESUMO
BACKGROUND: Taxotere (docetaxel) at the dose of 75 mg/m(2) every 3 weeks is a standard therapy for pretreated non-small-cell lung cancer (NSCLC). The aim of this study was to evaluate the safety profile of two schedules of docetaxel administration (every 3 weeks versus weekly) in patients with pretreated NSCLC. PATIENTS AND METHODS: From February 2000 to February 2001, 125 patients with locally advanced or metastatic NSCLC were randomised after failure of a previous platinum-based regimen to receive either docetaxel 75 mg/m(2) administered every 3 weeks (Dq3w) or docetaxel 40 mg/m(2) given weekly for 6 weeks followed by 2 weeks of rest (Dqw). Safety evaluations focused on grade 3-4 neutropenia, febrile neutropenia, nausea-vomiting and asthenia. RESULTS: Patients' characteristics were well balanced between arms. The most common National Cancer Institute Common Toxicity Criteria (NCI-CTC) grade 3-4 toxicity was neutropenia, which occurred in 48.4% of Dq3w patients versus 15.9% of Dqw patients (P=0.001). In addition, febrile neutropenia were observed in 6.5% of patients in Dq3w versus 0% in Dqw. Grade 3-4 asthenia was more frequent in Dqw. Other non-haematological toxicities were very rare. Regarding efficacy, there was a trend towards a better disease control rate in Dq3w: 32.2% versus 25.4% in Dqw. Median time to progression and survival were rather similar in both arms, respectively: 2.1 months (range 2-3.2) and 5.8 months (range 4.0-7.0) in Dq3w and 1.8 months (range 1.6-2.3) and 5.5 months (range 3.7-6.6) in Dqw. CONCLUSIONS: While both schedules had a favourable safety profile, a significant lower rate of severe neutropenia was observed in the weekly arm. Both regimens had similar efficacy. The weekly regimen could be considered as a good alternative for patients at risk of severe neutropenia.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Taxoides/administração & dosagem , Taxoides/uso terapêutico , Adulto , Idoso , Antineoplásicos Fitogênicos/efeitos adversos , Astenia/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Docetaxel , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Neutropenia/induzido quimicamente , Análise de Sobrevida , Taxoides/efeitos adversos , Vômito/induzido quimicamenteRESUMO
Decreased body fat mass and liver steatosis have been reported in mice fed diets containing the conjugated linoleic acid trans-10,cis-12-C18:2 (CLA2), but not in those fed diets containing cis-9,trans-11-C18:2 (CLA1). Because the decrease in fatty acid (FA) oxidation may cause fat accumulation, we questioned whether the effects of both CLAs on enzyme activities and mRNA expression were related to liver FA oxidation. To address this question, 7-wk-old male C57BL/6J mice were fed for 4 wk a diet supplemented with 1% CLA1, CLA2, or cis-9-C18:1 (control) esterified as triacylglycerols. In CLA2-fed mice, the proportions of CLA2 in the total FA of liver lipids were substantially lower than those of CLA1 in mice fed CLA1. The mitochondrial protein content per total liver was about 56% greater in CLA2-fed mice than in CLA1-fed mice and controls. Mitochondrial carnitine palmitoyltransferase I (CPT I) and carnitine-dependent palmitate oxidation activities were also significantly greater in CLA2-fed mice than in the two other groups. The amounts of malonyl-CoA per gram of liver and the sensitivity of CPT I to malonyl-CoA inhibition were greater in both groups of CLA-fed mice than in the controls. L-CPT I mRNA expression doubled in CLA2-fed mice and was 3 and 2 times greater for M-CPT I in the CLA1 and CLA2 groups, respectively, compared with controls. Peroxisomal FA oxidation-related activities and acyl-CoA oxidase mRNA expression were increased in CLA1-fed mice, and to a larger extent in CLA2-fed mice, relative to controls. These data indicate that FA oxidation capacities were increased in mice fed CLA2, but were likely depressed in vivo through malonyl-CoA inhibition.
Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos/metabolismo , Fígado Gorduroso/etiologia , Ácidos Linoleicos Conjugados/administração & dosagem , Animais , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Esterificação , Fígado/química , Masculino , Malonil Coenzima A/análise , Malonil Coenzima A/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/enzimologia , Oxirredução , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/metabolismoRESUMO
BACKGROUND: The survival benefit associated with first-line chemotherapy in advanced lung cancer led to the need for second-line chemotherapy. Docetaxel (Taxotere) has proven efficacy in both settings. This study evaluated the safety and efficacy of two doses of docetaxel in patients with non-small-cell lung cancer who had failed first-line platinum-based chemotherapy. PATIENTS AND METHODS: In total, 182 patients from 24 French centres were randomised and treated with either docetaxel 75 mg/m(2) (arm A) or 100 mg/m(2) (arm B) every 3 weeks. Baseline characteristics were well balanced, except more patients in arm A had metastatic disease (91.4% versus 78.7%) and therefore the median number of sites involved for arm A was three compared with two for arm B. RESULTS: Median time to treatment failure was 1.34 months [95% confidence interval (CI) 1.28-1.64] for arm A and 1.64 months (95% CI 1.34-2.62) for arm B. Median overall survival was 4.7 months (95% CI 3.8-5.9) for arm A versus 6.7 months (95% CI 4.8-7.1) for arm B. According to a blinded expert panel, disease control was achieved in 35 (43.8%) patients in arm A and 39 (49.4%) patients in arm B. More patients in arm B experienced grade 3-4 neutropenia (B: 72.7% versus A: 44.0%), asthenia (B: 20.2% versus A: 10.8%) and infection (B: 6.7% versus A: 2.2%). Three treatment-related deaths were reported in each arm. CONCLUSIONS: The optimal docetaxel dosage in this second-line setting is 75 mg/m(2), as it has a more favourable safety profile and on balance a similar efficacy to the 100 mg/m(2) dose.
Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Taxoides/efeitos adversos , Taxoides/uso terapêutico , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Docetaxel , Relação Dose-Resposta a Droga , Feminino , Humanos , Infusões Intravenosas , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neutropenia/induzido quimicamente , Segurança , Análise de Sobrevida , Taxoides/administração & dosagem , Fatores de Tempo , Falha de Tratamento , Resultado do TratamentoRESUMO
INTRODUCTION: Pubic osteomyelitis has been described in three situations: children in whom Staphylococcus aureus is the preeminent pathogen; elderly patients who have undergone genitourinary procedures, and parenteral drug abusers. In contrast, pubic osteomyelitis in athletes has been described less often. We report three cases of acute staphylococcal pubic osteomyelitis in young athletic men and present a review of the literature. EXEGESIS: The clinical presentation in each case was acute groin, hip, or perineal pain; fever; inability to bear weight; and pubic symphysis tenderness. The diagnosis was established by blood culture and radiologic changes. CONCLUSIONS: Staphylococcus aureus pubic osteomyelitis should be suspected in athletes who have febrile hip or groin pain. The pathogenesis of this disease is thought to involve preexisting trauma or athletic injury and subsequent seeding of this area during transient bacteremia. Prolonged antimicrobial therapy is required for the cure, and debridement with curettage may be necessary if patients have persistent infection or sequestra.
Assuntos
Osteomielite/patologia , Osso Púbico/microbiologia , Esportes , Infecções Estafilocócicas/complicações , Adolescente , Adulto , Traumatismos em Atletas/complicações , Bacteriemia , Desbridamento , Humanos , Masculino , Osteomielite/etiologia , Osteomielite/terapia , Dor/etiologia , Osso Púbico/patologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidadeRESUMO
Rumenic acid (cis-9, trans-11-C(18:2)) represents approx. 80% of conjugated linoleic acid (CLA) in dairy products. CLA has been shown to exert beneficial effects on health, but little work has been devoted to the ability to oxidize CLA isomers and the role of these isomers in the modulation of beta-oxidation flux. In the present study, respiration on rumenic acid was compared with that on linoleic acid (cis-9, cis-12-C(18:2)) with the use of rat liver mitochondria. In state-3, respiration was decreased by half with rumenic acid in comparison with linoleic acid. In the uncoupled state, respiration on CLA remained 30% lower. The lower ability to oxidize CLA was investigated through characterization of the enzymic steps. Rumenic acid was 33% less activated by acyl-CoA synthase than was linoleic acid. However, after such activation, the transfer of both acyl moieties to carnitine by carnitine acyltransferase I (CAT I) was of the same order. Moreover, CAT II activity was comparable with either isomer. After prior incubation with rumenic acid, oxidation of octanoic acid by re-isolated mitochondria was unimpaired, but that of palmitoleic acid was impaired unless linoleic acid was used in the prior incubation. The slower respiration on cis-9, trans-11-C(18:2) is suggested to arise from lower carnitine-acylcarnitine translocase activity towards the acylcarnitine form, causing an upstream increase in the corresponding acyl-CoA.
Assuntos
Respiração Celular , Ácido Linoleico/metabolismo , Mitocôndrias Hepáticas/metabolismo , Animais , Caprilatos/metabolismo , Carnitina Aciltransferases/metabolismo , Bovinos , Coenzima A Ligases/metabolismo , Laticínios , Ácidos Graxos Monoinsaturados/metabolismo , Ácido Linoleico/química , Fígado/citologia , Fígado/metabolismo , Consumo de Oxigênio , Ratos , Ácidos Esteáricos/metabolismo , EstereoisomerismoRESUMO
The aim of this study was to evaluate the efficacy of docetaxel as first-line chemotherapy in patients with unresectable metastatic or locally advanced pancreatic adenocarcinoma and to further characterise the safety and pharmacokinetic profiles of docetaxel. 43 patients were enrolled into this phase II study. Treatment consisted of a 1-h infusion of docetaxel 100 mg/m2 every 3 weeks without premedication with corticosteroids until progression or unacceptable toxicity occurred. Dose modifications were planned for adverse events. Patients were observed for 1 month after the last docetaxel infusion, to document any late adverse events, with a follow-up every 3 months until death. Response rate and duration were the major efficacy endpoints. Response status was reviewed by an external independent panel. Pharmacokinetic analysis was performed during the first treatment cycle. 40 patients were evaluable for response, and all were evaluable for safety. After independent review, partial response was recorded in 6 patients (overall response rate, 15%; 95% confidence limit (CI), 7.7-29.8%) and stable disease was recorded in 15 patients (38%). The median duration of response was 5.1 months (range: 3.1-7.2). The median pain control time was 4.5 months (range: 0-8) and the median time to performance status worsening was 2.3 months (range: 0-4.5). Most patients 40 (93.0%) received a relative dose intensity of more than 70% of the planned dose. The incidence and severity of adverse events reflected the known safety profile for docetaxel. Docetaxel clearance was reduced in patients with elevated concentrations of hepatic enzymes or bilirubin. Docetaxel is an active agent for unresectable metastatic or locally advanced pancreatic adenocarcinoma.
Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Paclitaxel/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Taxoides , Adenocarcinoma/metabolismo , Adolescente , Adulto , Idoso , Antineoplásicos/farmacocinética , Docetaxel , Feminino , França , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Paclitaxel/farmacocinética , Paclitaxel/uso terapêutico , Neoplasias Pancreáticas/metabolismo , Análise de Sobrevida , Resultado do TratamentoRESUMO
Some metabolic effects of dietary marine oils, or of dietary eicosapentaenoic or docosahexaenoic acid are reviewed. It is pointed out that docosahexaenoic acid appears more effective as regards induction of peroxisomal beta-oxidation. Similarly, docosahexaenoic appears more powerful in terms of suppression of hepatic delta9-desaturase activity and mRNA-levels. The potential inhibitory effect of polyunsaturated fatty acids, particularly docosahexaenoic acid, on mitochondrial beta-oxidation is discussed. Experiments with rats suggesting that the hypolipidaemic response of eicosapentaenoic acid is more marked when the fatty acid was given to fed rats, as compared to fasted rats, are discussed.
Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/farmacologia , Mitocôndrias/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Animais , Humanos , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos , Peroxissomos/efeitos dos fármacos , Peroxissomos/metabolismoRESUMO
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 DioxigenaseRESUMO
(i) Highly purified mitochondrial fractions were practically devoid of microsomal contamination and of acyl-CoA ligase activity. (ii) In mitochondria, glycerol-3-phosphate acyltransferase (GPAT) activity was supported by two enzymes, the first being very active at low palmitoyl-CoA/albumin ratios and sensitive to external agents (external form), the second being detected only at higher palmitoyl-CoA/albumin ratios and insensitive to external agents (internal form). (iii) Carnitine palmitoyltransferase I (CPT I) activity was shown to inhibit external GPAT activity only. (iv) Glycerol-3-phosphate exerted an inhibitory effect on CPT I, even when GPAT was inactive. Reciprocal interaction of CPT I and GPAT was discussed with regard to the balance existing between fatty acid oxidation and esterification metabolic pathways.
Assuntos
Carnitina O-Palmitoiltransferase/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Mitocôndrias Hepáticas/enzimologia , Animais , Biomarcadores , Fracionamento Celular , Centrifugação com Gradiente de Concentração , Coenzima A Ligases/análise , Homeostase , Cinética , Masculino , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/ultraestrutura , Mitocôndrias Hepáticas/ultraestrutura , Monoaminoxidase/análise , Povidona , Ratos , Ratos Wistar , Dióxido de SilícioRESUMO
(1) Effects of dietary treatment of male albino rats with eicosapentaenoic acid (EPA) or docosahexaenoic acid on hepatic mitochondrial lipid metabolism have been investigated. (2) Mitochondria isolated from rats given these treatments were shown to have increased ability to respire on acyl-CoA esters in the presence of malonate. This effect was expressed with most of the long-chain acyl-CoA esters used as substrates. When malonate in the incubations was replaced with malate, mitochondria from treated animals were found to exhibit diminished rates of respiration on polyunsaturated acyl-CoA esters, in particular linolenoyl-, eicosapentaenoyl- and docosahexaenoyl-CoA. This phenomenon could not be attributed to changes in activity of carnitine palmitoyltransferase I or in peroxisomal beta-oxidation. (3) Uncoupled respiration on glutamate, malate or succinate was also affected by treatment with EPA. With liver mitochondria isolated from rats that had been treated with a omega-3 fatty acid in the fasted state, the respiratory rates were lower than those observed with mitochondria isolated from control rats. Respiratory rates with mitochondria isolated from rats given the omega-3 fatty acid in the fed state was not significantly different from control rates. (4) In rats treated with EPA in the fed state, the amount of EPA incorporated into mitochondrial lipids was markedly more increased as compared to rats given omega-3 fatty acid in the fasted state. Incorporation of dietary EPA into tissue lipids was investigated, also following mildronate treatment of rats (an inhibitor of carnitine biosynthesis). (5) A hypolipidaemic effect of dietary EPA was only observed when the fatty acid was given to fed rats. Rats treated with EPA in the fasted state, in contrast, exhibited hypoglycaemia, the hypolipidaemic effects now being absent. (6) These results suggest that hypolipidaemia is most pronounced when the metabolic state favours incorporation of dietary EPA into body lipids rather than its beta-oxidation, as mediated by the fed/fasted transition or by treatment with mildronate.
Assuntos
Dieta , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Metabolismo dos Lipídeos , Fígado/metabolismo , Mitocôndrias Hepáticas/metabolismo , Animais , Óleos de Peixe , Peroxidação de Lipídeos , Fígado/ultraestrutura , Masculino , Ratos , Ratos WistarRESUMO
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 DioxigenaseRESUMO
The five-fold higher carnitine content in the liver of fenofibrate-treated rats addresses the question about the possible role of this enhancement in the hypolipidaemic effect of the drug and the underlying mechanisms. When fenofibrate was administered with mildronate (a gamma-butyrobetaine hydroxylase inhibitor) in suitable amount, the content in carnitine was found to be normalized in liver. However, triglyceride contents of liver and serum were then at least as low as in rats treated by fenofibrate only. When carnitine concentration was lowered by mildronate to the third of the normal value, a marked increase in triglycerides occurred both in liver and serum, while the five-fold increase in carnitine due to fenofibrate enhanced blood ketone body concentration with no effect on liver and serum triglycerides. Data suggest that the normal carnitine concentration is largely sufficient to meet the usual requirement for carnitine palmitoyltransferase I activity (CPT I). In rat liver, increase in mitochondrial CPT I activity and in peroxisomal fatty acid oxidation may constitute part of the hypolipidaemic effect of fenofibrate.
Assuntos
Carnitina/metabolismo , Fenofibrato/farmacologia , Hipolipemiantes/farmacologia , Fígado/metabolismo , Metilidrazinas/farmacologia , Animais , Carnitina/sangue , Colesterol/sangue , Colesterol/metabolismo , Corpos Cetônicos/sangue , Corpos Cetônicos/metabolismo , Masculino , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Fosfolipídeos/sangue , Fosfolipídeos/metabolismo , Ratos , Ratos Wistar , Triglicerídeos/metabolismoRESUMO
Extradural arachnoid cysts are uncommon expanding lesions in the spinal canal which may communicate with the subarachnoid space. Usually in the lower thoracic spine, they may cause symptoms by compressing the spinal cord or nerve roots. We report cases of thoracic and lumbar arachnoid cysts studied by cystography, myelography, CT and MRI. These techniques showed extradural cystic lesions containing cerebrospinal fluid, with variable communication with the subarachnoid space, causing anterior displacement and flattening of the spinal cord.
Assuntos
Cistos Aracnóideos/diagnóstico , Diagnóstico por Imagem , Adolescente , Adulto , Aracnoide-Máter/patologia , Humanos , Vértebras Lombares/patologia , Masculino , Exame Neurológico , Vértebras Torácicas/patologiaRESUMO
Paraneoplastic limbic encephalitis is a rare syndrome mostly associated with small cell lung cancer. We present the case of a 69-year-old man with selective amnesia suggesting limbic encephalitis. A neuroendocrine cell lung cancer was found, confirming the diagnosis of paraneoplastic limbic encephalitis. Contrast-enhanced cerebral CT was normal whether magnetic resonance imaging showed signal abnormalities of the medial part of temporal lobes and hippocampal regions. Because neurologic improvement may follow treatment of the primary tumor, early diagnosis is important.
Assuntos
Neoplasias Brônquicas/complicações , Carcinoma Neuroendócrino/complicações , Encefalite/etiologia , Sistema Límbico , Síndromes Paraneoplásicas , Idoso , Encefalite/diagnóstico , Encefalite/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
We report a case of arteriovenous fistula due to spontaneous rupture of an aortic aneurysm into the inferior vena cava. This is a rare complication of atheromatous aneurysm, often difficult to diagnose as the clinical presentation may be obscure. Although aortography is the reference diagnostic investigation, spiral CT acquisition with 3D and 2D reformation allowed visualization of the arteriovenous communication and provided an accurate diagnosis.
Assuntos
Aneurisma da Aorta Abdominal/complicações , Doenças da Aorta/diagnóstico por imagem , Ruptura Aórtica/complicações , Fístula Arteriovenosa/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Veia Cava Inferior , Idoso , Idoso de 80 Anos ou mais , Doenças da Aorta/diagnóstico , Fístula Arteriovenosa/diagnóstico , Humanos , MasculinoRESUMO
This study was designed to determine which enzyme activities were first impaired in mitochondria exposed to 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), a known radical initiator. EPR spin-trapping revealed generation of reactive oxygen species although malondialdehyde formation remained very low. With increasing AAPH concentrations, State-3 respiration was progressively depressed with unaltered ADP/O ratios. A top-down approach demonstrated that alterations were located at the phosphorylation level. As shown by inhibitor titrations, ATP/ADP translocase activity was unaffected in the range of AAPH concentrations used. In contrast, AAPH appeared to exert a deleterious effect at the level of F1F0-ATPase, comparable with dicyclohexylcarbodi-imide, which alters Fo proton channel. A comparison of ATP hydrolase activity in uncoupled and broken mitochondria reinforced this finding. In spite of its pro-oxidant properties, AAPH was shown to act as a dose-dependent inhibitor of cyclosporin-sensitive permeability transition initiated by Ca2+, probably as a consequence of its effect on F1F0-ATPase. Resveratrol, a potent antiperoxidant, completely failed to prevent the decrease in State-3 respiration caused by AAPH. The data suggest that AAPH, when used under mild conditions, acted as a radical initiator and was capable of damaging F1F0-ATPase, thereby slowing respiratory chain activity and reducing mitochondrial antioxidant defences.
Assuntos
Amidinas/farmacologia , Membranas Intracelulares/fisiologia , Mitocôndrias Hepáticas/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , ATPases Translocadoras de Prótons/metabolismo , Animais , Atractilosídeo/análogos & derivados , Atractilosídeo/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Óxidos N-Cíclicos , Dicicloexilcarbodi-Imida/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Radicais Livres/metabolismo , Membranas Intracelulares/efeitos dos fármacos , Cinética , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/análise , Potenciais da Membrana/fisiologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , ATPases Translocadoras de Prótons/efeitos dos fármacos , Ratos , Ratos Wistar , Marcadores de Spin , Succinatos/metabolismoRESUMO
We report an 18-year-old woman with a giant cell tumour of the sphenoid bone. CT demonstrated a lytic soft-tissue mass arising from the sphenoid body, extending to the left petrous apex and into the nasopharynx. On MRI the tumour had nonspecific signal intensity, but there was contrast enhancement on both examinations. CT was better for showing the extent of the osseous disease, whereas MRI was more accurate as regards soft-tissue extension.
Assuntos
Tumor de Células Gigantes do Osso/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias Cranianas/diagnóstico , Seio Esfenoidal/patologia , Tomografia Computadorizada por Raios X , Adolescente , Craniotomia , Feminino , Seguimentos , Tumor de Células Gigantes do Osso/patologia , Tumor de Células Gigantes do Osso/cirurgia , Humanos , Neoplasias Cranianas/patologia , Neoplasias Cranianas/cirurgia , Seio Esfenoidal/cirurgiaRESUMO
This study was designed to examine whether short- and long-term treatments by a low level of dietary L-carnitine are capable of altering enzyme activities related to fatty acid oxidation in normal Wistar rats. Under controlled feeding, ten days of treatment changed neither body weights nor liver and gastrocnemius weights, but succeeded in reducing the weight of peri-epididymal adipose tissues. Triacylglycerol contents were lowered in liver and ketone body concentrations were found slightly more elevated in blood. In the liver, mitochondrial carnitine palmitoyltransferase I (CPT I) exhibited a slightly higher specific activity and a lower sensitivity to malonyl-CoA inhibition, while peroxisomal fatty acid oxidizing system (PFAOS) was found to be less active. Carnitine supplied for one month reduced the mass of the periepididymal fat tissue, but not those of the other studied organs, and produced a slight but non-significant gain in body weight after ten days of treatment. In the liver, CPTI characteristics were comparable in control and treated groups, while PFAOS activity was less in rats receiving carnitine. Data show that L-carnitine at a low level in the diet exerted two paradoxical effects before and after ten days of treatment. Results are discussed in regard to fatty acid oxidation in mitochondria and peroxisomes, and to the possible altered acyl-CoA/acylcarnitine ratio with increased concentrations of L-carnitine in the liver.
Assuntos
Carnitina/administração & dosagem , Ácidos Graxos/metabolismo , Fígado/metabolismo , Animais , Peso Corporal , Carnitina/farmacocinética , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina O-Palmitoiltransferase/metabolismo , Dieta , Corpos Cetônicos/sangue , Corpos Cetônicos/metabolismo , Masculino , Microcorpos/metabolismo , Mitocôndrias/metabolismo , Tamanho do Órgão , Oxirredução , Ratos , Ratos Wistar , Distribuição Tecidual , Triglicerídeos/sangue , Triglicerídeos/metabolismoRESUMO
This study was designed to examine whether the depletion of L-carnitine may induce compensatory mechanisms allowing higher fatty acid oxidative activities in liver, particularly with regard to mitochondrial carnitine palmitoyltransferase I activity and peroxisomal fatty acid oxidation. Wistar rats received D-carnitine for 2 days and 3-(2,2,2,-trimethylhydrazinium)propionate (mildronate), a noncompetitive inhibitor of gamma-butyrobetaine hydroxylase, for 10 days. They were starved for 20 hr before being sacrificed. A dramatic reduction in carnitine concentration was observed in heart, skeletal muscles and kidneys, and to a lesser extent, in liver. Triacylglycerol content was found to be significantly more elevated on a gram liver and whole liver basis as well as per mL of blood (but to a lesser extent), while similar concentrations of ketone bodies were found in the blood of D-carnitine/mildronate-treated and control rats. In liver mitochondria, the specific activities of acyl-CoA synthetase and carnitine palmitoyltransferase I were enhanced by the treatment, while peroxisomal fatty acid oxidation was higher per gram of tissue. It is suggested that there may be an enhancement of cellular acyl-CoA concentration, a signal leading to increased liver fatty acid oxidation in acute carnitine deficiency.