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1.
J Environ Manage ; 268: 110670, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510432

RESUMO

Integrated forest management (IFM) can help reconcile critical trade-offs between goals in forest management, such as nature conservation and biomass production. The challenge of IFM is dealing with these trade-offs at the level of practical forest management, such as striving for compromises between biomass extraction and habitat retention. This paper reviews some of the driving factors that influence the integration of nature conservation into forest management. The review was conducted in three steps - a literature review, an expert workshop and an expert-based cooperative analysis. Of 38 driving factors identified, three were prioritised by more of the participants than any of the others: two are socio-cultural factors, identity (how people identify with forest) as well as outreach and education, and one is economic - competitiveness in forest value chains. These driving factors correspond to what are considered in the literature as enablers for IFM. The results reveal that targeted, group-oriented, adaptive and innovative policy designs are needed to integrate nature conservation into forest management. Further, the results reveal that a "one-size-fits-all" governance approach would be ineffective, implying that policy instruments need to consider contextually specific driving factors. Understanding the main driving factors and their overall directions can help to better manage trade-offs between biodiversity conservation and biomass production in European forests.


Assuntos
Agricultura Florestal , Madeira , Biodiversidade , Conservação dos Recursos Naturais , Europa (Continente) , Florestas , Árvores
2.
Eur J Clin Pharmacol ; 69(3): 533-40, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22983312

RESUMO

PURPOSE: Cisplatin during hyperthermic intraperitoneal chemotherapy (HIPEC) has not previously been measured with a selective technique. The primary aims were to examine the pharmacokinetics of active cisplatin and its monohydrated complex (MHC) during HIPEC using a specific measuring technique, to compare cisplatin's systemic absorption with oxaliplatin, and to compare active cisplatin levels to that of total platinum. METHODS: Ten patients treated with cytoreductive surgery and HIPEC (cisplatin 50 mg/m(2),doxorubicin 15 mg/m(2)) were recruited. Blood and perfusate samples were drawn during and after HIPEC. Cisplatin analysis was conducted using liquid chromatography (LC) with post-column derivatization with diethyldithiocarbamate and compared with inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS: The mean half-life (t1/2) of perfusate cisplatin was 18.4 min, with area under the time-concentration curve (AUC) 0-90 min of 2.87 mM·min and estimated 0-60 min of 2.45 mM·min. The absorption t1/2 was 9.0 min for cisplatin and 18.2 min for oxaliplatin. The ratio of total platinum to active cisplatin increased in a linear manner by time of perfusion. CONCLUSIONS: Cisplatin is absorbed quicker than oxaliplatin. Lowering the perfusion time to 60 min does not significantly change the pharmacokinetics of cisplatin, and is therefore to be considered. As the HIPEC perfusion progresses, the ICP-MS technique does not adequately reflect active cisplatin levels in the perfusate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carcinoma/tratamento farmacológico , Hipertermia Induzida , Neoplasias Peritoneais/tratamento farmacológico , Adulto , Idoso , Área Sob a Curva , Carcinoma/sangue , Carcinoma/cirurgia , Quimioterapia Adjuvante , Cromatografia Líquida , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Monitoramento de Medicamentos/métodos , Feminino , Meia-Vida , Humanos , Infusões Parenterais , Modelos Lineares , Masculino , Espectrometria de Massas , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Compostos Organoplatínicos/farmacocinética , Oxaliplatina , Neoplasias Peritoneais/sangue , Neoplasias Peritoneais/cirurgia
3.
Eur J Clin Pharmacol ; 64(9): 907-11, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18563401

RESUMO

OBJECTIVE: To evaluate the perfusate and systemic kinetics of oxaliplatin during hyperthermic intraperitoneal chemotherapy (HIPEC) using a selective analytical technique. METHODS: HIPEC was carried out in eight patients by the open abdomen coliseum technique for 30 min at 41.5-43 degrees C with an average of 427 mg/m(2) of oxaliplatin in 5% dextrose solution. Blood and perfusate samples were collected during the perfusion. Additional blood samples were taken up to 2 h after the end of perfusion. The analysis was performed by liquid chromatography and post-column derivatization with N,N-diethyldithiocarbamate using microwave heating. RESULTS: The mean elimination half-life of oxaliplatin in the perfusate was 29.5 min (range 21.1-41.2 min) and in the peripheral circulation 24.7 min (range 21.7-27.7 min). The ratio of the areas under the time concentration curve in perfusate and blood was 12.8 +/- 2.9. CONCLUSION: The systemic exposure of oxaliplatin measured after HIPEC using a selective analytical technique is considerably lower than previously reported results obtained by atomic absorption spectroscopy.


Assuntos
Antineoplásicos/administração & dosagem , Hipertermia Induzida , Compostos Organoplatínicos/administração & dosagem , Adulto , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Área Sob a Curva , Vias de Administração de Medicamentos , Feminino , Meia-Vida , Humanos , Infusões Parenterais , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/sangue , Compostos Organoplatínicos/farmacocinética , Oxaliplatina , Perfusão
4.
Ann Oncol ; 17(2): 252-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16291583

RESUMO

BACKGROUND: The efficacy of oxaliplatin combined with capecitabine (XELOX) as second-line therapy in patients with advanced colorectal cancer (ACRC) resistant to irinotecan is not well established. Oxaliplatin induces acute, cold-induced neuropathy in most patients. The incidence is claimed to be infusion rate-dependent and therefore a 2-h infusion is recommended. PATIENTS AND METHODS: For practical and economic reasons, but also for patient's convenience, we performed a phase II study to examine XELOX30 (capecitabine 1000 mg/m2 orally twice daily on days 1-14 and oxaliplatin 130 mg/m2 as a 30 min infusion on day 1) in patients with ACRC resistant to irinotecan. In addition the pharmacokinetics of oxaliplatin was studied. RESULTS: From November 2002 to September 2003, 70 patients with ACRC were treated with XELOX30. Median age was 62 (range 33-74 years) years and median performance status was 1 (range 0-2). The median number of courses was four (range 1-12) and median cumulative dose of oxaliplatin was 530 (range 125-1560) mg/m2. The response rate was 17% (95% CI 10-23), median time to progression (TTP) was 5.4 months (95% CI 4.6-6.4) and median survival 9.5 months (95% CI 8.5-11.2). White blood cell count (WBC) and performance status were significantly correlated to TTP. Neurotoxicity was moderate: grade 1 56%, grade 2 17% and grade 3 6%. Other grade 3 toxicities were nausea/vomiting 9%, diarrhoea 14% and PPE 8%. The maximum blood concentration and total body clearance of oxaliplatin was higher than previously reported in studies examining 2-h infusions, but the volume of distribution and terminal half-life was in close agreement with previous results. CONCLUSION: XELOX30 is a very convenient second-line regimen in ACRC with an activity and safety profile similar to other oxaliplatin schedules.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adenocarcinoma/mortalidade , Administração Oral , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Capecitabina , Neoplasias Colorretais/mortalidade , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Humanos , Infusões Intravenosas , Irinotecano , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Falha de Tratamento
5.
Med Oncol ; 19(4): 261-5, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12512920

RESUMO

Oxaliplatin is a novel platinum complex used for the treatment of metastatic colorectal carcinoma. The pharmacokinetics of the free fraction of oxaliplatin in blood were evaluated in 10 patients given 85 mg/m2 of oxaliplatin using an infusion time of 2 h. Blood samples were collected during and after the infusion and immediately placed on ice. The samples were ultrafiltrated centripetally and the concentration of oxaliplatin in the ultrafiltrate was determined by liquid chromatography in combination with postcolumn derivatization. The in vitro degradation rate was determined in blood from the patients taken immediately before drug administration. The maximal blood concentration (C(max)) and terminal half-life (t1/2) were 1.44 +/- 0.20 (SD) microg/mL and 14.1 min (range: 10.2-24.5), respectively. The area under the blood concentration time curve (AUC), clearance (CL), and distribution volume (V(ss)) were (means +/- SD) 161 +/- 22 microg min/mL, 32.1 +/- 4.2 L/h/m2, and 0.26 +/- 0.06 L/kg, respectively. There was a significant correlation between the clearance of oxaliplatin in the patients and the degradation rate in whole blood (r = 0.746; p = 0.017). Oxaliplatin has a short elimination half-life, which is in a sharp contrast to previously reported elimination half-lives obtained by analysis of the platinum content in plasma and ultrafiltrate. The correlation between in vivo and in vitro data suggests that the degradation in whole blood plays a role for the elimination of the drug.


Assuntos
Antineoplásicos/farmacocinética , Compostos Organoplatínicos/farmacocinética , Idoso , Feminino , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Oxaliplatina
6.
Hear Res ; 140(1-2): 38-44, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10675634

RESUMO

Cisplatin (8 mg/kg) was given intravenously to guinea pigs either as a 15 s bolus injection (25 animals) or as a 1 h infusion (28 animals). To determine the influence of the mode of cisplatin administration and pharmacokinetics on the ototoxic side-effect, the concentrations of cisplatin and the biotransformation product monoaquated cisplatin were determined in blood ultrafiltrate using liquid chromatography with post-column derivatization. Ototoxic effect was evaluated as difference in pre- and 96 h post-exposure auditory brainstem response (ABR) threshold. The cisplatin peak concentration was considerably higher, 19.2+/-2.4 microg/ml, in the bolus injection group than in the infusion group, 6.7+/-0.5 microg/ml (mean+/-S.E.M.). The area under the blood ultrafiltrate concentration time curve (AUC) for cisplatin was slightly greater in the infusion group, 442+/-26 microg/ml/min, than in the bolus injection group, 340+/-5 microg/ml/min. For monoaqua cisplatin, the AUC was not different between the groups (bolus injection: 30.8+/-1. 5 microg/ml/min, infusion: 34.1+/-3.3 microg/ml/min). A significant ototoxic effect was observed in both groups at 20 and 12.5 kHz, but there was no difference between the groups in the extent of threshold shift. The interindividual variability in susceptibility to ABR threshold shift was far greater than the variability in pharmacokinetics, suggesting that other factors are more important in determining the degree of hearing loss.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Surdez/induzido quimicamente , Animais , Antineoplásicos/farmacocinética , Área Sob a Curva , Limiar Auditivo/efeitos dos fármacos , Cisplatino/farmacocinética , Creatinina/sangue , Surdez/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Cobaias , Infusões Intravenosas , Injeções Intravenosas , Taxa de Depuração Metabólica
7.
Eur J Pharm Sci ; 7(2): 87-91, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9845784

RESUMO

The chemical stability of 5-aminolevulinic acid (ALA) was studied in aqueous solution as a function of concentration, pH, temperature and in the presence of ethylenediaminetetraacetic acid (EDTA). The degradation of ALA was followed by reversed-phase liquid chromatography using a pH where ALA is protonated (pKa1=3.90; pKa2=8. 05, as determined potentiometrically). ALA was degraded by a reaction following second order kinetics. Stock solutions of 1% (60 mM) ALA were incubated at 50 degrees C. At pH 2.35, ALA was stable during the whole incubation period (37 days). The half-lives for the second-order decomposition of 1% ALA at pH 4.81 and 7.42 were 257 and 3.0 h, respectively. The degradation rate increased about 1.5 times with each 10 degrees C rise in temperature at pH 7.53 within the range studied (37-85 degrees C). The energy of activation, Ea, for the second-order decomposition of ALA was 43.7 kJmol-1. EDTA did not influence the degradation of ALA when a mixture of 1% ALA and 1% EDTA was incubated at pH 7.42.


Assuntos
Ácido Aminolevulínico/química , Estabilidade de Medicamentos , Ácido Edético/farmacologia , Concentração de Íons de Hidrogênio , Soluções , Temperatura
9.
Cancer Lett ; 132(1-2): 175-80, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-10397471

RESUMO

This paper examines the monohydrated complex of cisplatin (MHC) with respect to kinetics and cytotoxicity. Equilibrium mixtures of cisplatin and hydrated species have been used in previous studies of a similar nature. To our knowledge, this is the first paper examining MHC after isolation and quantification. This was accomplished using liquid chromatography with porous graphitic carbon. MHC and cisplatin were quantified over time in a suspension of the small-cell lung cancer cell line U-1285. Cytotoxicity was evaluated using the fluorescent microculture cytotoxicity assay. MHC was significantly more cytotoxic than cisplatin at the high end of the drug concentrations tested. In culture media with low chloride ion concentrations, the stability of MHC was related to changes in pH. At a pH of between 6.0 and 7.2, MHC was rapidly converted to cisplatin. In culture media with a pH above 7.2, MHC was considerably more stable. These findings might have clinical significance given that MHC circulates in the blood stream of patients receiving cisplatin infusions and that solid tumours often have environments that are extremely acidotic.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Antineoplásicos/farmacocinética , Cisplatino/farmacocinética , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Cinética , Testes de Toxicidade , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
10.
J Intern Med ; 242(3): 199-211, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9350164

RESUMO

AIMS: To report levels of cardiovascular risk factors in 1985, 1990 and 1995 in three population samples in Göteborg, Sweden, and to compare with previous population risk factor levels. POPULATION: The study was performed within the framework of the WHO MONICA Project which compares risk factor levels as well as the incidence of coronary heart disease and stroke in 38 populations. METHODS: Three random samples of men and women aged 25-34, 35-44, 45-54 and 55-64 comprising 152-218 subjects in each age group who responded to the invitation for screening procedures which included questionnaires, physical and laboratory investigations in 1985, 1990 and 1995. RESULTS: More men than women had smoked, except for those aged 35-44 where there was no difference between men and women. The proportion of men who had smoked decreased strongly between the first and third investigations (P < 0.0001), particularly amongst the younger age-groups, with a similar tendency amongst women. In the 25-44-years age group there was a tendency towards more women than men to be smokers in 1995. Snuff was used by 27% and 19% of men aged 25-34 and 35-44 years, respectively, in 1995. Up to 5% of women used snuff; higher in the younger age groups. More young men than women reported regular physical activity during leisure time with a tendency towards an increase from 1985 to 1995. The proportion of men reporting psychological stress varied little over the study period, but women aged 25-34 reported increased stress from 1985 to 1995. Body weight increased whereas height remained stable and consequently body mass index increased in men and women (P = 0.0001). Similarly, waist:hip ratio (measured in 1990 and 1995 only) also increased (P = 0.0001). Mean systolic and diastolic blood pressure increased with age and there was also a small increase between 1985 and 1995. Systolic blood pressure increased by a mean of 1.24 mmHg per 5-year period independent of sex and age (P = 0.0001). Antihypertensive treatment increased with age, but was stable between 1985 and 1995. Serum total and LDL cholesterol concentrations increased with age, and there was a nonsignificant tendency also to higher HDL cholesterol concentrations at older ages. Serum total cholesterol concentration declined between 1985 and 1995, and HDL cholesterol declined significantly between 1985 and 1995 in all age groups for men and women only when all age groups were analysed together. Similar to total cholesterol, levels of LDL cholesterol declined between 1985 and 1995 for all ages. Serum triglyceride levels increased for men and women between 1985 and 1995.


Assuntos
Doenças Cardiovasculares/etiologia , Adulto , Peso Corporal , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/psicologia , Exercício Físico , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Estresse Psicológico/complicações , Suécia , Tabagismo/complicações
11.
Blood ; 84(7): 2144-50, 1994 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7919328

RESUMO

Busulfan is widely used as a component of the myeloablative therapy in bone marrow transplantation. Recent studies have shown that the drug disposition is altered in children and is associated with less therapeutic effectiveness, lower toxicities, and higher rates of engraftment failure. We have evaluated the bioavailability of the drug in two groups of patients: eight children between 1.5 and 6 years of age and eight older children and adults between 13 and 60 years. Oral bioavailability showed a large interindividual variation. In children, the bioavailability ranged from 0.22 to 1.20, and for adults, it was within the range 0.47 to 1.03. The elimination half-life after intravenous administration in children (2.46 +/- 0.27 hours; mean +/- SD) did not differ from that obtained for adults (2.61 +/- 0.62 hours). However, busulfan clearance normalized to body weight was significantly higher in children (3.62 +/- 0.78 mL.min-1.kg-1) than that in adults (2.49 +/- 0.52 mL.min-1.kg-1). Also, the distribution volume normalized for body weight was significantly higher in children (0.74 +/- 0.10 L.kg-1) compared with 0.56 +/- 0.10 L. kg-1 in adults. The difference in clearance between children and adults was not statistically significant when normalized to body surface area, which most probably shows that busulfan dosage should be calculated on the basis of surface area rather than body weight. However, to avoid drug-related toxicities, drug monitoring and an individual dose adjustment should be considered because of the variability in busulfan bioavailability.


Assuntos
Bussulfano/farmacocinética , Administração Oral , Adulto , Fatores Etários , Disponibilidade Biológica , Pré-Escolar , Feminino , Humanos , Lactente , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
12.
Eur J Clin Pharmacol ; 46(4): 375-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7957526

RESUMO

5-Methoxypsoralen (5-MOP) in combination with ultraviolet light exposure is used for the treatment of psoriasis. The effect of food on the pharmacokinetics of 5-MOP was evaluated in a randomized, crossover study in nine healthy subjects. Each subject received the tablets with a standardized breakfast or under fasting conditions. The food had a dramatic effect on the bioavailability of 5-MOP. Five of the subjects showed no measurable quantities (detection limit of the analytical technique 1 ng.ml-1) of 5-MOP when the drug was given under fasting conditions. However, plasma peak concentration within the range 37-144 ng.ml-1 (median 102 ng.ml-1) was measured when the drug was taken with food. The time for the plasma peak concentration was within the range 2.0-5.1 h (median 3.0 h) under non-fasting conditions. The elimination half-life was within the range 1.4-2.7 h (median 1.9 h). We conclude that it is imperative that 5-MOP tablets are administered together with food.


Assuntos
Alimentos , Metoxaleno/análogos & derivados , 5-Metoxipsoraleno , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Jejum/sangue , Feminino , Meia-Vida , Humanos , Masculino , Metoxaleno/farmacocinética , Pessoa de Meia-Idade , Comprimidos
13.
Cancer Chemother Pharmacol ; 33(3): 181-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8269597

RESUMO

The pharmacokinetics of high-dose busulphan was studied in 17 patients during conditioning prior to bone marrow transplantation using deuterium-labeled busulphan (d8-BU). About 50% of busulphan doses 1 and 16 was replaced with d8-BU. Patients were treated with phenytoin or diazepam as prophylactic anticonvulsant therapy. Patients who received phenytoin demonstrated significantly higher clearance (mean +/- SD, 3.32 +/- 0.99 ml min-1 kg-1), a lower area under the concentration-time curve (AUC, 5,412 +/- 1,534 ng h ml-1; corrected for dose/kilogram) and a shorter elimination half-life (3.03 +/- 0.57 h) for the last dose of d8-BU (dose 16) as compared with the first dose (2.80 +/- 0.78 ml min-1 kg-1, 6,475 +/- 2,223 ng h ml-1 and 3.94 +/- 1.10 h, respectively). No difference in the above mentioned pharmacokinetic parameters was seen in patients treated with diazepam. Moreover, a continuous decrease in the steady-state level of busulphan was observed in four of seven patients in the phenytoin-treated group, whereas in the diazepam group, such a decrease was seen in only one of eight patients. We conclude that phenytoin used as prophylactic anticonvulsant therapy alters busulphan pharmacokinetics and, most probably, its pharmacodynamics. For adequate prophylactic therapy, anticonvulsants with fewer enzyme-inductive properties than phenytoin should be used.


Assuntos
Bussulfano/farmacocinética , Diazepam/uso terapêutico , Doença de Hodgkin/metabolismo , Leucemia/metabolismo , Fenitoína/uso terapêutico , Adulto , Transplante de Medula Óssea , Bussulfano/administração & dosagem , Bussulfano/sangue , Terapia Combinada , Diazepam/farmacologia , Interações Medicamentosas , Feminino , Meia-Vida , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/terapia , Humanos , Leucemia/tratamento farmacológico , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Fenitoína/farmacologia , Convulsões/prevenção & controle
15.
Cancer Chemother Pharmacol ; 31(4): 265-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8422688

RESUMO

Peptichemio (PTC) is a mixture of six synthetic oligopeptides, each of which contains the alkylating residue m-[di(2-chloroethyl)amino]-L-phenylalanine (L-mSL). The fate of PTC was investigated in eight patients with multiple myeloma after intravenous infusion of the drug. The quantitative analysis of the plasma samples was performed by liquid chromatography with fluorometric detection. L-mSL was rapidly released from the peptides and reached its maximal plasma concentration at the end of the infusion. Its median elimination half-life was 1.73 (range, 0.72-2.41) h. It was possible to follow the concentration of only one of the peptides, L-mSL-L-Arg(NO2)-L-Nval.OEt, during and shortly after the infusion of PTC. The stability of L-mSL and the peptides was studied in buffer solution (pH 7.3), plasma, and blood. The stability of some of the peptides was drastically decreased in blood, the degradation half-lives being only about 1 min. We conclude that L-mSL plays an important role in the mechanism of action of PTC.


Assuntos
Melfalan/farmacocinética , Mieloma Múltiplo/metabolismo , Peptiquímio/farmacocinética , Idoso , Idoso de 80 Anos ou mais , Feminino , Meia-Vida , Humanos , Infusões Intravenosas , Masculino , Melfalan/sangue , Melfalan/metabolismo , Pessoa de Meia-Idade , Peptiquímio/sangue , Peptiquímio/uso terapêutico
16.
Cancer Chemother Pharmacol ; 28(2): 130-4, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2060084

RESUMO

Busulphan levels in plasma were measured in 27 patients during conditioning therapy (1 mg/kg x 4 for 4 days) before bone marrow transplantation. The mean minimal concentration found in children aged less than 5 years (237 ng ml-1) was lower than that observed in adults or older children (607 and 573 ng ml-1, respectively). The AUC for the last dose was significantly lower in young children (2.315 h ng ml-1) than in adults or older children (6,134 and 5,937 h ng ml-1, respectively). The elimination half-life for the last dose in young children was shorter (2.05 h) than that in either adults (2.59 h) or older children (2.79 h). When the AUC was normalized for body surface area, the difference between young children and the other groups was smaller but remained statistically significant. The total body clearance was significantly higher in young children (7.3 ml min-1 kg-1) as compared with both older children and adults (3.02 and 2.7 ml min-1 kg-1, respectively). The plasma levels of busulphan showed circadian rhythmicity, especially in young children. The concentration measured during the night in some patients was up to 3-fold that observed during daytime. We conclude that the busulphan dosage for children must be reconsidered and that further studies are urgently needed to develop an optimal therapy.


Assuntos
Envelhecimento/metabolismo , Bussulfano/farmacocinética , Adolescente , Adulto , Bussulfano/sangue , Criança , Pré-Escolar , Fenômenos Cronobiológicos , Ritmo Circadiano , Relação Dose-Resposta a Droga , Feminino , Meia-Vida , Humanos , Lactente , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
17.
Clin Pharmacol Ther ; 47(1): 86-90, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2295223

RESUMO

The influence of interferon-induced fever on oral melphalan pharmacokinetics has been studied in 10 myeloma patients in a randomized crossover design. The melphalan dose (0.25 mg/kg) was given alone and 5 hours after the administration of human interferon alpha (7 x 10(6) IU/m2), respectively. The plasma concentration of melphalan was determined by liquid chromatography with fluorometric detection after derivatization of melphalan with N-acetylcysteine. The area under the plasma concentration-time curve (AUC) was significantly lower (p = 0.02) when melphalan was given with interferon. There was a significant negative correlation (p = 0.008) between body temperature and dose normalized AUC, whereas no effect was noticed on the maximum plasma concentration (Cmax) and on the time to obtain Cmax. The rate of elimination showed a tendency (p = 0.06) to increase with increasing body temperature. It is suggested that the cytotoxicity of the drug is most probably enhanced because of the higher alkylating activity of the compound at elevated body temperatures.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Febre/metabolismo , Interferon Tipo I/efeitos adversos , Melfalan/farmacocinética , Mieloma Múltiplo/metabolismo , Idoso , Temperatura Corporal , Interações Medicamentosas , Feminino , Febre/etiologia , Meia-Vida , Humanos , Interferon Tipo I/administração & dosagem , Masculino , Melfalan/administração & dosagem , Melfalan/sangue , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Prednisona/administração & dosagem
18.
Eur J Cancer Clin Oncol ; 25(5): 899-903, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2737222

RESUMO

The impact of renal function on oral melphalan pharmacokinetics was studied in 15 patients with multiple myeloma. A two-fold interindividual variation in the plasma concentration-time curve (AUC) was found. An increase in AUC and melphalan mean residence time (MRT) was noted in patients with renal dysfunction. No correlation was found between GFR and the terminal plasma half-life time. We conclude from these results that renal dysfunction is associated with an increase in AUC and MRT of oral melphalan. A careful follow-up of hematological toxicity and possibly a dose reduction of melphalan are proposed for myeloma patients with renal impairment.


Assuntos
Rim/fisiopatologia , Melfalan/farmacocinética , Mieloma Múltiplo/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Taxa de Filtração Glomerular , Humanos , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico
19.
Eur J Clin Pharmacol ; 36(5): 525-30, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2753072

RESUMO

The pharmacokinetics of high-dose busulphan was studied in adult patients with acute myeloblastic leukaemia after oral doses of 1 mg.kg-1 every 6 h for 4 days. The mean steady-state plasma concentration was 1080 ng/ml-1 during the treatment. Individual steady-state concentrations after the last dose on average were 32% lower than those predicted from total AUC measurements following the first dose. Mean elimination half-life in plasma was 2.3 h after the last dose and 3.4 h after the first dose which suggests that busulfan may increase its own metabolic rate on repeated treatment. The cerebrospinal fluid/plasma concentration ratio of busulphan was 1.3. Busulphan showed insignificant protein binding in plasma (7.4%). About 2% of the dose was excreted unchanged in the urine. For the first time sulpholane, 3-hydroxysulpholane and tetrahydrothiophene 1-oxide were identified as urinary metabolites of busulphan in man.


Assuntos
Bussulfano/farmacocinética , Adulto , Biotransformação , Bussulfano/administração & dosagem , Bussulfano/metabolismo , Feminino , Meia-Vida , Humanos , Hidrólise , Leucemia Mieloide Aguda/metabolismo , Pessoa de Meia-Idade , Modelos Biológicos , Ligação Proteica
20.
Bone Marrow Transplant ; 4(1): 113-4, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2647175

RESUMO

A patient with acute myeloblastic leukemia received high-dose busulfan (1 mg/kg by mouth every 6 h for 4 days) as myelo-ablative therapy for autologous bone marrow transplantation. Rapid entry of busulfan into the cerebrospinal fluid (CSF) was observed. Plasma and CSF concentrations of busulfan were comparable during the 4 days of treatment. The elimination half-lives of busulfan in plasma and CSF were 2.6 h and 2.8 h respectively during the first 12 h after the last dose.


Assuntos
Bussulfano/farmacocinética , Transplante de Medula Óssea , Bussulfano/administração & dosagem , Bussulfano/sangue , Bussulfano/líquido cefalorraquidiano , Meia-Vida , Humanos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/líquido cefalorraquidiano , Leucemia Mieloide Aguda/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas , Cuidados Pré-Operatórios
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