RESUMO
Lactic acid bacteria (LAB) coexist with Clostridium spp. in hydrogen production processes from complex substrates; however, the role of LAB is still unclear. This study analyzed the fermentation products in a wide range of initial pH (pHi, 5.5-6.9) and total solids (TS%, 8-22%) to determine the activity of these two microbial groups over time (from 24 to 120 h). Agave bagasse served as the feedstock for hydrogen production via consolidated bioprocess (CBP), while the inoculum source was the indigenous mature microbiota. In the early stage of the CBP, hydrogen production from lactic acid occurred only at pHi ≥ 6.0 (ρ = 0.0004) with no effect of TS%; lactic acid accumulated below this pHi value. In this stage, lactic acid production positively correlated with a first cluster of LAB represented by Paucilactobacillus (r = 0.64) and Bacillus (r = 0.81). After 72 h, hydrogen production positively correlated with a second group of LAB led by Enterococcus (r = 0.71) together with the hydrogen producer Clostridium sensu stricto 1 (r = 0.8) and the acetogen Syntrophococcus (r = 0.52) with the influence of TS% (ρ < 0.0001). A further experiment showed that buffering the pH to 6.5 increased and lengthened the lactic acid production, doubling the hydrogen production from 20 to 41 mL H2/gTSadded. This study confirmed the prevalence of distinct groups of LAB over time, whose microbial activity promoted different routes of hydrogen production.
Assuntos
Agave , Celulose , Lactobacillales , Hidrogênio , Fermentação , Ácido Láctico , Concentração de Íons de HidrogênioRESUMO
The simultaneous capture and detection of biomolecules is crucial for revolutionizing bioanalytical platforms in terms of portability, response time and cost-efficiency. Herein, we demonstrate how the sensitivity to external stimuli and changes in the local electronic environment of silver clusters lead to an advantageous biosensing platform based on the fluorometric response of bioactive luminescent silver clusters (BioLuSiC) confined in faujasite X zeolites functionalized with antibodies. The photoluminescence response of BioLuSiC was enhanced upon immunocomplex formation, empowering a wash-free and quick biodetection system offering optimal results from 5â min. Proteins and pathogens (immunoglobulin G and Escherichia coli) were targeted to demonstrate the biosensing performance of BioLuSiC, and a human serum titration assay was also established. BioLuSiC will pave the way for innovative bioanalytical platforms, including real-time monitoring systems, point-of-care devices and bioimaging techniques.
Assuntos
Técnicas Biossensoriais , Zeolitas , Humanos , Prata , Escherichia coli , Luminescência , Imunoglobulina G , Técnicas Biossensoriais/métodosRESUMO
BACKGROUND: Appendix' anatomical variations are a rare occurrence which can mislead diagnosis and delay appropriate treatment. CASE PRESENTATION: We present a 9-year-old female patient that came with a clinical picture compatible with acute appendicitis. However, a cecal mass was identified instead of an inflamed appendix during surgery. Therapeutic decisions were extremely challenging due to clinical deterioration and an uncertain etiology. Only the histopathology report revealed the presence of a complete subserosal appendix which was responsible for the entire symptomatology. Here, we review all case reports regarding intramural, intracecal or subserosal appendixes. A discussion of the general approach to this specific case and the importance of consensual diagnostic criteria for these specimens are also presented. At last, an incidental finding is exposed and final treatment options are discussed given the overall presentation. CONCLUSIONS: Considering these variants would guide physicians towards a more accurate approach to similar clinical pictures and hence an improved long-term prognosis.
Assuntos
Apendicite , Apêndice , Doenças do Ceco , Tumores Neuroendócrinos , Apendicite/diagnóstico , Apendicite/cirurgia , Apêndice/cirurgia , Criança , Feminino , HumanosRESUMO
The aim of this work was to evaluate the effect of different inorganic compounds as electron donors for the capture of CO2 from a model cement flue gas CO2 /O2 /N2 (4.2:13.5:82.3% v/v) using a non-photosynthetic microbial community. The inoculum obtained from a H2 -producing reactor was acclimated to CO2 consumption achieving 100% of CO2 removal after 45 days. Na2 S, MnCl2 , NaNO2 , NH4 Cl, Na2 S2 O3 , and FeCl2 were used as energy source for CO2 fixation by the acclimated microbial community showing different efficiencies, being Na2 S the best electron donor evaluated (100% of CO2 consumption) and FeCl2 the less effective (28% of CO2 consumption). In all treatments, acetate and propionate were the main endpoint metabolites. Moreover, scaling the process to a continuous laboratory biotrickling filter using Na2 S as energy source showed a CO2 consumption of up to 77%. Analysis of the microbial community showed that Na2 S and FeCl2 exerted a strong selection on the microbial members in the community showing significant differences (PERMANOVA, p = 0.0001) compared to the control and the other treatments. Results suggest that the CO2 fixing pathways used by the microbial community in all treatments were the 3-hydroxypropionate-4-hydroxybutyrate cycle and the Wood-Ljungdahl pathway.
Assuntos
Dióxido de Carbono , Microbiota , Dióxido de Carbono/metabolismo , ElétronsRESUMO
Adjuvant chemotherapy prolongs survival in patients with breast cancer, but it also causes side effects such as ovarian-function suppression. The incidence of chemotherapy-induced amenorrhea (CIA) varies depending on the patients' age, dose and the type of chemotherapy that they receive. CIA produced by anthracycline-based regimens has been widely studied, but less is known about the incidence of CIA caused by the combined use of taxanes and anthracyclines. It has been suggested that tamoxifen might influence the maintenance of amenorrhea. However, most studies of CIA have explored series of patients with hormone-sensitive and hormone-resistant tumors, so data about CIA could be strongly influenced by endocrine adjuvant therapy. The aims of our study were to assess the incidence of CIA with the addition of taxanes to anthracyclines regimens in pre- or perimenopausal patients diagnosed with hormone-sensitive breast cancer and to determine predictive factors for CIA. A retrospective non-randomized study was conducted in the Hospital Clinico Universitario of Valencia, Spain. Three hundred and five premenopausal and perimenopausal patients were recruited between January 1998 and May 2005, 212 of whom had been treated with anthracycline-based regimens and 93 with a combination of anthracyclines and taxanes. Amenorrhea was permanent in 222 patients (93.7%) and menses returned in 6.3%. CIA was present in 75.5% of patients treated with anthracyclines and in 82.7% of patients treated with anthracyclines and taxanes. This difference did not reach statistical significance (p = 0.16). CIA appeared in 95% of patients older than 45 years, while the proportion of CIA decreased to 52% in patients younger than 40 years. This suggests age as an important predictive factor for CIA (p < 0.001). Although a slightly superior incidence of CIA in patients with hormone-sensitive tumors treated with combination regimens was observed, no statistically significant difference in incidence was found. Age was found to be the main predictive factor for CIA in both groups.
Assuntos
Amenorreia/induzido quimicamente , Amenorreia/epidemiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Adulto , Fatores Etários , Antraciclinas/administração & dosagem , Antraciclinas/efeitos adversos , Neoplasias da Mama/patologia , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Hormônio-Dependentes/patologia , Estudos Retrospectivos , Taxoides/administração & dosagem , Taxoides/efeitos adversosRESUMO
In this work, the expression of an α-amylase from Bacillus megaterium on the cell surface of Escherichia coli strains WDHA (Δ hycA and Δ ldhA) and WDHFP (Δ hycA, Δ frdD and Δ pta) by the autodisplay adhesin involved in diffuse adherence (AIDA) system was carried out with the purpose to confer the ability to E. coli strains to degrade starch and thus produce hydrogen, ethanol and succinic acid. For the characterization of the biocatalyst, the effect of temperature (30-70⯰C), pH (3-6) and CaCl2 concentration (0-25â¯mM), as well as the thermostability of the biocatalyst (55-80⯰C) at several time intervals (15-60â¯min) were evaluated. The results showed that the biocatalyst had a maximum activity at 55⯰C and pH 4.5. Calcium was required for the activity as well for the thermal stability of the biocatalyst. The calculated Vmax and Km values were 0.24 U/cm3 and 5.8â¯mg/cm3, respectively. Furthermore, a set of anaerobic batch fermentations was carried out using 10â¯g/dm3 of starch and 1â¯g/dm3 of glucose as carbon sources in 120â¯cm3 serological bottles, using WDHA and WDHFP strains harboring the pAIDA-amyA plasmid. The hydrogen production for WDHA was 1056.06â¯cm3/dm3 and the succinic acid yield was 0.68â¯g/gstarch, whereas WDHFP strain produced 1689.68â¯cm3/dm3 of hydrogen and an ethanol yield of 0.28â¯g/gstarch. This work represents a promising strategy to improve the exploitation of starchy biomass for the production of biofuels (hydrogen and ethanol) or succinate without the need of a pre-saccharification process.
Assuntos
Bacillus megaterium/enzimologia , Etanol/metabolismo , Hidrogênio/metabolismo , Amido/metabolismo , Ácido Succínico/metabolismo , alfa-Amilases/metabolismo , Bacillus megaterium/genética , Biocombustíveis , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Temperatura , alfa-Amilases/genéticaRESUMO
STUDY OBJECTIVE: The primary aim of this study is to show the non-inferiority of 15mg intraoperative dose of ketorolac as compared to the standard 30mg ketorolac by looking at the visual analog scale pain (VAS) scores 4h after an adult spine surgery. DESIGN: The study design is a prospective randomized non-inferiority clinical trial looking at non-inferiority of intraoperative 15mg ketorolac from the standard 30mg dose. SETTING: Quaternary care center. PATIENTS: 50 adult (18-65years of age) undergoing lumbar decompression spine surgery. INTERVENTIONS: Group A received a single intraoperative dose of 15mg ketorolac at the end of surgery and group B received single intraoperative dose of 30mg ketorolac. MEASUREMENTS: The primary outcome was the visual analog scale (VAS) pain scores 4h after an adult spine surgery. Secondary measures were morphine usage in the first 8 and 24h postoperatively, numeric rating scores (NRS) up to 24h, sedation, nausea, vomiting, respiratory depression, pruritus and bleeding complications. MAIN RESULTS: Intention to treat analysis showed a mean increase in 4h VAS pain score of 7.9mm (95% CI: -4.5mm to 20.4mm) in patients administered 15mg ketorolac. This difference was neither statistically (P=0.207) nor clinically significant (<18mm on VAS scale). A similar increase in the 15mg group was noted through a per protocol analysis, 6.9mm (95% CI: -6.6mm to 20.5mm, P=0.307) greater in the 15mg group. Non-inferiority of 15mg was not confirmed. No significant difference was found in secondary endpoints. CONCLUSIONS: Ketorolac 30mg intravenous was not superior to 15mg intravenous for post-operative pain management after spine surgery. However, 15mg failed to meet the pre-specified criteria for non-inferiority to the 30mg dose.
Assuntos
Inibidores de Ciclo-Oxigenase/administração & dosagem , Cuidados Intraoperatórios/métodos , Cetorolaco/administração & dosagem , Laminectomia/efeitos adversos , Região Lombossacral/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Adulto , Idoso , Analgésicos Opioides/uso terapêutico , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Injeções Intravenosas , Cuidados Intraoperatórios/efeitos adversos , Cetorolaco/farmacologia , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Náusea/induzido quimicamente , Náusea/epidemiologia , Medição da Dor , Hemorragia Pós-Operatória/induzido quimicamente , Hemorragia Pós-Operatória/epidemiologia , Estudos Prospectivos , Prurido/epidemiologia , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/epidemiologia , Resultado do Tratamento , Vômito/induzido quimicamente , Vômito/epidemiologiaRESUMO
PURPOSE: To establish the safety, pharmacokinetic parameters, maximum-tolerated dose, and recommended dose of aplidine, a novel marine cyclodepsipeptide, in patients with advanced cancer. PATIENTS AND METHODS: Using a modified Fibonacci method, we performed a phase I and pharmacokinetic study of aplidine administered as a 24-hour intravenous infusion every 2 weeks. RESULTS: Sixty-seven patients received aplidine at a dose ranging from 0.2 to 8 mg/m(2). Dose-limiting myotoxicity corresponding to grade 2 to 3 creatine phosphokinase elevation and grade 1 to 2 myalgia and muscle weakness occurred in two of six patients at 6 mg/m(2). No cardiac toxicity was observed. Electron microscopy analysis showed the disappearance of thick filaments of myosin. Grade 3 muscle toxicity occurred in three of 14 patients at the recommended dose of 5 mg/m(2) and seemed to be more readily reversible with oral carnitine (1 g/10 kg). Therefore, dose escalation was resumed using carnitine prophylactically, allowing an increase in the recommended dose to 7 mg/m(2). Other toxicities were nausea and vomiting, diarrhea, asthenia, and transaminase elevation with mild hematologic toxicity. Aplidine displayed a long half-life (21 to 44 hours), low clearance (45 to 49 L/h), and a high volume of distribution (1,036 to 1,124 L) with high interpatient variability in plasma, whereas in whole blood, clearance ranged from 3.0 to 6.2 L/h. Minor responses and prolonged tumor stabilizations were observed in patients with medullary thyroid carcinoma. CONCLUSION: Muscle toxicity was dose limiting in this study. Recommended doses of aplidine were 5 and 7 mg/m(2) without and with carnitine, respectively. The role of carnitine will be further explored in phase II studies.
Assuntos
Antineoplásicos/farmacocinética , Depsipeptídeos/farmacocinética , Metástase Neoplásica/tratamento farmacológico , Neoplasias/metabolismo , Adolescente , Adulto , Idoso , Antineoplásicos/efeitos adversos , Carnitina/uso terapêutico , Depsipeptídeos/efeitos adversos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Infusões Intravenosas , Masculino , Dose Máxima Tolerável , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos , Complexo Vitamínico B/uso terapêuticoRESUMO
PURPOSE: The purpose of this study was to (a) assess the feasibility of administering ecteinascidin-743 (ET-743), a novel DNA minor-groove disrupting agent of marine origin, administered as a daily i.v. infusion for 5 days every 3 weeks; (b) recommend a dose for Phase II studies; (c) characterize its pharmacokinetic behavior; and (d) seek preliminary evidence of anticancer activity. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated with escalating doses of ET-743 as a daily 1-h i.v. infusion for 5 days every 3 weeks. Plasma and urine were sampled on both days 1 and 5 of the first course. Pharmacokinetic parameters were related to the principal toxicities. RESULTS: Forty-two patients were treated with 118 courses of ET-743 at doses ranging from 6 to 380 microg/m(2)/day. Elevations in hepatic transaminases were common at ET-743 dose levels > or =216 microg/m(2)/day, resolved rapidly, and were never dose limiting nor cumulative. Instead, hematological toxicity was the principal toxicity that precluded dose escalation. The maximum tolerated dose of ET-743 that could be administered repetitively was 325 microg/m(2)/day. Antitumor activity was noted in three patients with leiomyosarcoma and primary peritoneal and ovarian carcinomas. The pharmacokinetics of ET-743 were dose independent, and drug accumulation over the 5 days of treatment was modest, with the ratio of the area under the plasma-versus-time curve on day 5 to that on day 1 averaging 2.05. The volume of distribution at steady state was large (mean, 1037 liters/m(2)), and the mean terminal half life on day 5 was 26.81 h. CONCLUSIONS: The maximum tolerated dose of ET-743 that can be administered repetitively is 325 microg/m(2)/day daily x 5 every 3 weeks, which is recommended for disease-directed clinical trials. The acceptable toxicity profile of ET-743 on the divided-dose schedule evaluated in this trial, as well as the generally superior antitumor activity associated with divided-dose schedules in preclinical studies, provides a rationale for further evaluation of ET-743 on this administration schedule.
Assuntos
Antineoplásicos Alquilantes/farmacocinética , Dioxóis/farmacocinética , Isoquinolinas/farmacocinética , Neoplasias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/metabolismo , Área Sob a Curva , Aspartato Aminotransferases/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Fígado/efeitos dos fármacos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Tetra-Hidroisoquinolinas , Fatores de Tempo , Distribuição Tecidual , TrabectedinaRESUMO
PURPOSE: Ecteinascidin 743 (ET-743) is a potent cytotoxic alkaloid of marine origin that has shown promising evidence of antitumor activity during phase I clinical trials. In the study reported here, the influence of clinical characteristics and pretreatment pathophysiological variables on the pharmacokinetics of ET-743 and their associations with drug-related toxicity was examined in sarcoma patients treated in three phase II clinical trials. METHODS: Adult patients with various histological subtypes of soft tissue sarcoma received 1.5 mg/m(2) of ET-743 by 24-h continuous i.v. infusion once every 3 weeks. Eligibility criteria were similar for each study, except for the histological subtype of the tumor or the extent of prior treatment with other anticancer agents, and all patients had normal or near-normal liver and renal function. The maximum plasma concentration (C(max)) and area under the plasma profile from time zero to infinity (AUC) of the drug were determined during the first cycle of therapy. Patients were evaluated for toxicity every week. RESULTS: Geometric mean +/- SD values of the pharmacokinetic parameters in 69 patients were: C(max) 1.14 +/- 0.52 ng/ml, AUC 39.9 +/- 16.6 ng.h/ml, and total body clearance (CL) 36.7 +/- 16.4 l/h per m(2). The only significant correlation involving physical characteristics of the patients or pretreatment pathophysiological variables was a very weak relationship between alkaline phosphatase and AUC (r=0.39, P<0.01). The 15 patients with any baseline liver function test exceeding the upper limit of the normal ranges had a significantly greater (P=0.02) incidence of severe toxicity (80% vs 44%). Although the mean AUC of ET-743 in patients with elevated serum levels of hepatic enzymes was 17% greater than that in patients with normal pretreatment liver function tests, the difference was not significant ( P=0.22). In addition, there was no distinct relationship between the grade of the most severe drug-related toxicity that occurred during the first cycle of therapy and the AUC for the entire cohort. The CL of ET-743 was found to be 27% greater in patients concurrently receiving dexamethasone as a preventative antiemetic than in those who were not, but the difference did not achieve statistical significance (P=0.08). There were no significant associations between CL (liters per hour) and body surface area or any other variable related to body size. CONCLUSIONS: The risk of developing severe toxicity was substantially enhanced in patients with relatively moderate indications of hepatic dysfunction without a coincident effect on the CL of ET-743. Dexamethasone cotreatment appeared to decrease the incidence of severe toxicity as well as the AUC of the drug. Delivering a fixed amount of drug without adjustment for the height or weight of the patient may be more appropriate than dose normalization due to the absence of an association between CL and body surface area. Optimizing dosing strategies to further enhance the therapeutic index of ET-743 may depend upon obtaining a better understanding of the metabolic fate of the drug in humans.
Assuntos
Antineoplásicos/farmacocinética , Dioxóis/farmacocinética , Isoquinolinas/farmacocinética , Sarcoma/tratamento farmacológico , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Dexametasona/farmacologia , Dioxóis/administração & dosagem , Dioxóis/efeitos adversos , Humanos , Infusões Intravenosas , Isoquinolinas/administração & dosagem , Isoquinolinas/efeitos adversos , Testes de Função Hepática , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Tetra-Hidroisoquinolinas , Trabectedina , Transaminases/sangueRESUMO
PURPOSE: To study the prognostic significance of the presence of breast cancer-specific mRNA transcripts in peripheral blood (PB), defined by serial analysis of gene expression, in high-risk breast cancer (HRBC) patients undergoing high-dose chemotherapy after receiving adjuvant chemotherapy. METHODS: From 1994 to 2000, 84 HRBC patients (median age, 44 years; > 10 nodes; 74%) received adjuvant chemotherapy (fluorouracil, epirubicin, and cyclophosphamide for six cycles [83%] or doxorubicin and cyclophosphamide followed by paclitaxel) before undergoing one course of cyclophosphamide plus thiotepa plus carboplatin (STAMP V). Radiotherapy or hormone therapy was administered whenever indicated. Aliquots of apheresis-mononuclear blood cells were frozen from each patient. mRNA was isolated using an automatic nucleic acid extractor based on the magnetic beads technology; reverse transcription was performed using random hexamers. Cytokeratin 19, HER-2, P1B, PS2, and EGP2 transcripts were quantified to B-glucuronidase by real-time polymerase chain reaction (RT-PCR) using a linear DNA probe marked with a quencher and reporter fluorophores used in RT-PCR. Presence of PB micrometastases, estrogen receptor and progesterone receptor status, tumor size, age, tumor grade, number of nodes affected, and treatment with paclitaxel were included in the statistical analysis. RESULTS: Median follow-up was 68.3 months (range, 6 months to 103 months). Forty-seven relapses (56%) and 35 deaths (41.7%) were registered. Both tumor size and presence of micrometastases reached statistical significance according to the Cox multivariate model. Relapse hazard ratio (HR) for those patients with PB micrometastases was 269% (P = .006); death HR, 300% (P = .011). Time relapse was 53 months longer for patients without micrometastases: 31.3 v 84.2 months (P = .021). CONCLUSION: PB micrometastases presence after adjuvant chemotherapy predicts both relapse and death more powerful than classical factors in HRBC patients undergoing high-dose chemotherapy. Micrometastases search using a gene panel appears to be a more accurate procedure than classical approaches involving only one or two genes.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Transplante de Células-Tronco de Sangue Periférico , Precursores de RNA/sangue , Adulto , Idoso , Antígenos de Superfície/genética , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/sangue , Neoplasias da Mama/química , Neoplasias da Mama/terapia , Proteínas de Ligação ao Cálcio/genética , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Epirubicina/administração & dosagem , Molécula de Adesão da Célula Epitelial , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Queratinas/genética , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Paclitaxel/administração & dosagem , Valor Preditivo dos Testes , Presenilina-2 , Prognóstico , RNA Mensageiro , RNA Neoplásico , Receptor ErbB-2/genética , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Tiotepa/administração & dosagem , Resultado do TratamentoRESUMO
Ecteinascidin 743 (ET-743) is an anticancer agent derived from the Caribbean tunicate Ecteinascidia turbinata. In the present article, the pharmacokinetics and pharmacodynamics of ET-743 are described within a phase I study. Forty patients with solid tumors initially received ET-743 as a 1-h i.v. infusion every 21 days at nine dose levels (50-1100 microg/m(2)). The maximal tolerated dose (MTD) was 1100 microg/m(2), with thrombocytopenia and fatigue as dose-limiting toxicities (DLTs). As this MTD was substantially lower than in parallel phase I studies, dose escalation continued using a prolonged, 3-h infusion. Thirty-two patients were entered at five dose levels (1000-1800 microg/m(2)). The MTD was 1800 microg/m(2) with pancytopenia and fatigue as DLTs. The recommended phase II dose was 1650 microg/m(2) given over 3 h at which 12 patients were treated. Pharmacokinetic monitoring was performed for both treatment schedules. Non-compartmental pharmacokinetic parameters at the recommended dose with the 3-h infusion were (mean value+/-SD): clearance 87+/-30 l/h and mean elimination half-life 26+/-7 h. Pharmacokinetics were linear at the dose range tested with this schedule. The percentage decrease in platelets, white blood cells and neutrophils correlated with the area under the plasma concentration versus time curve (AUC), dose and maximal plasma concentration (C(max)). Hepatic toxicity increased with dose, AUC and C(max). Administration of 1650 microg/m(2) ET-743 over 3 h seemed clinically feasible; pharmacokinetics were linear with this schedule. Hepatic and hematological toxicities correlated with exposure to ET-743.
Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Dioxóis/administração & dosagem , Isoquinolinas/administração & dosagem , Adulto , Idoso , Animais , Antineoplásicos Alquilantes/efeitos adversos , Antineoplásicos Alquilantes/farmacocinética , Área Sob a Curva , Dioxóis/efeitos adversos , Dioxóis/farmacocinética , Fadiga/induzido quimicamente , Feminino , Meia-Vida , Humanos , Infusões Intravenosas , Isoquinolinas/efeitos adversos , Isoquinolinas/farmacocinética , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Tetra-Hidroisoquinolinas , Trombocitopenia/induzido quimicamente , Fatores de Tempo , Trabectedina , Urocordados/químicaRESUMO
BACKGROUND: Recurrent osteosarcoma is a drug-resistant disease with a dismal prognosis. The objective of this Phase II study was to evaluate the activity of ecteinascidin 743 (ET-743) as a salvage therapy in these patients. METHODS: Patients with recurrent osteosarcoma who had received standard chemotherapeutic agents were eligible. ET-743 was administered at a dose of 1500 microg/m(2) as a 24-hour infusion every 3 weeks. Pharmacokinetic studies were performed during the first cycle. RESULTS: Twenty-five patients were enrolled, 23 of whom were assessable for response (median age of 18 years; range, 12-67 years). The median number of previous chemotherapeutic agents was five (range, three to eight previous agents). Sixty-one cycles were administered (median number of cycles per patient was 2; range, 1-9 cycles per patient). Three patients (12%) achieved minor responses (49% 36% and 25%, respectively). Fifteen patients (60%) developed a transient elevation of hepatic transaminases (Grade 3 or 4 [according to the National Cancer Institute Common Toxicity Criteria]), which was not cumulative. Grade 3 or 4 neutropenia and thrombocytopenia were observed in 12 patients (48%) and 6 patients (24%), respectively. The mean area under the curve (AUC) in 4 patients experiencing Grade 4 toxicity (76.4 +/- 29.3 ng x hr/mL) was significantly greater (P = 0.034) than that in those for whom the most severe toxicity was Grade 3 (39.5 +/- 17.2 ng x hr/mL [n = 12]) or Grade 1-2 (52.6 +/- 15.6 ng x hr/mL [n = 5]). There were no other significant correlations found between pharmacokinetic variables and patient characteristics, toxicity, or therapeutic response. CONCLUSIONS: ET-743 was found to be well tolerated in heavily pretreated osteosarcoma patients but had limited antitumor activity as a single agent. The combination of ET-743 with cisplatin or doxorubicin should be considered.