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1.
J Econ Entomol ; 108(1): 192-200, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26470120

RESUMO

Anastrepha fraterculus (Wiedemann, 1830) is the main pest of temperate climate orcharding. The study investigated the development of A. fraterculus related to phenological stage of blueberry, blackberry, strawberry guava, and Surinam cherry trees. The phenological stages I (green fruits), II (intermediate ripening stage of fruits), and III (fruits close to harvesting) were determined, and they are from 8th, 10th, and 11th week; 6th, 8th, and 9th week; 8th, 13th, and 16th week; and 5th, 6th, and 7th week after the first flowering of blueberry, blackberry, strawberry guava, and Surinam cherry trees, respectively. We collected fruits from orchards to determine the infestation index using the formula: number of pupa/fruit weight. To investigate the development of A. fraterculus, we determined the following biological parameters: egg-to-adult period, weight of pupae, oviposition period, fecundity, number of pupae, and number of infested fruits. The infestation index for the fruits collected in the field was greater in strawberry guava and Surinam cherry fruits. In the laboratory, the development of A. fraterculus occurred in stage III of blueberry. In blackberry, besides stage III, we also observed the development in stage II, however, at lower infestation. In strawberry guava, the development of A. fraterulus occurred in stages II and III, and the development in both stages was similar. For Surinam cherry, the development occurred in the three phenological stages with similar values for biological parameters. Overall, of the four hosts studied, the strawberry guava and Surinam cherry fruits allowed a better biological development of A. fraterculus, corroborating its preference for fruits native to Brazil.


Assuntos
Mirtilos Azuis (Planta)/parasitologia , Frutas/parasitologia , Psidium/parasitologia , Rosaceae/parasitologia , Tephritidae/crescimento & desenvolvimento , Animais , Mirtilos Azuis (Planta)/crescimento & desenvolvimento , Feminino , Frutas/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Larva/crescimento & desenvolvimento , Masculino , Psidium/crescimento & desenvolvimento , Rosaceae/crescimento & desenvolvimento
2.
One Health ; 8: 100112, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31788532

RESUMO

The emergence, spread, and persistence of antimicrobial resistance (AMR) remains a pressing global concern. Increased promotion of commercial small-scale agriculture within low-resource settings has facilitated an increased use in antimicrobials as growth promoters globally, creating antimicrobial-resistant animal reservoirs. We conducted a longitudinal field study in rural Ecuador to monitor the AMR of Escherichia coli populations from backyard chickens and children at three sample periods with approximately 2-month intervals (February, April, and June 2017). We assessed AMR to 12 antibiotics using generalized linear mixed effects models (GLMM). We also sampled and assessed AMR to the same 12 antibiotics in one-day-old broiler chickens purchased from local venders. One-day-old broiler chickens showed lower AMR at sample period 1 compared to sample period 2 (for 9 of the 12 antibiotics tested); increases in AMR between sample periods 2 and 3 were minimal. Two months prior to the first sample period (December 2016) there was no broiler farming activity due to a regional collapse followed by a peak in annual farming in February 2017. Between sample periods 1 and 2, we observed significant increases in AMR to 6 of the 12 antibiotics in children and to 4 of the 12 antibiotics in backyard chickens. These findings suggest that the recent increase in farming, and the observed increase of AMR in the one-day old broilers, may have caused the increase in AMR in backyard chickens and children. Small-scale farming dynamics could play an important role in the spread of AMR in low- and middle-income countries.

3.
J Clin Oncol ; 11(11): 2194-204, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8229134

RESUMO

PURPOSE: We conducted a phase I and pharmacokinetic trial of CPT-11 (irinotecan) to characterize the maximum-tolerated dose (MTD), toxicities, pharmacokinetic profile, and antitumor effects in patients with refractory solid malignancies. PATIENTS AND METHODS: We treated 32 patients with CPT-11 administered as a 90-minute intravenous infusion every week for 4 consecutive weeks followed by a 2-week rest period. Dose levels ranged from 50 to 180 mg/m2/wk. We determined concentrations of the lactone (active) and total (lactone plus carboxylate) forms of CPT-11 and its metabolite, SN-38, in the plasma and urine of selected patients during and after drug infusion. RESULTS: Grade 4 diarrhea was the dose-limiting toxicity (DLT) at the 180-mg/m2/wk dose level. Other toxicities attributed to CPT-11 included dehydration, nausea, vomiting, and asthenia. Hematologic toxicity was mild in most patients. The terminal plasma half-life for CPT-11 (total) was 7.9 +/- 2.8 hours, for CPT-11 (lactone) 6.3 +/- 2.2 hours, for SN-38 (total) 13.0 +/- 5.8 hours, and for SN-38 (lactone) 11.5 +/- 3.8 hours. We observed significant correlations between drug dose and peak plasma concentration (Cpmax) and between drug dose and area under the concentration curve (AUC) for CPT-11, but not for SN-38. CONCLUSION: The MTD for CPT-11 in this patient population was 150 mg/m2/wk when administered on a weekly-times-four schedule repeated every 6 weeks. At dose levels greater than 150 mg/m2/wk, diarrhea is dose-limiting.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/análogos & derivados , Adulto , Idoso , Antineoplásicos Fitogênicos/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/farmacocinética , Cromatografia Líquida de Alta Pressão , Esquema de Medicação , Feminino , Humanos , Irinotecano , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico
4.
J Clin Oncol ; 15(3): 1087-93, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9060549

RESUMO

PURPOSE: Topotecan is a specific inhibitor of topoisomerase I. Recently bioavailability of an oral formulation of approximately 30% with limited variability was reported. We conducted a phase I and pharmacokinetic study of the oral formulation of topotecan to characterize the maximum-tolerated dose (MTD), toxicities, pharmacokinetics, and antitumor effects in patients with refractory malignancies. PATIENTS AND METHODS: Patients were treated with oral topotecan given twice daily for 21 days, with cycles repeated every 28 days. In subsequent cohorts, the dose was escalated from 0.15 to 0.6 mg/m2 twice daily. Pharmacokinetics were performed on day 1 and 8 of the first course using a validated high-performance liquid chromatographic assay and noncompartmental pharmacokinetic methods. RESULTS: Thirty-one patients entered the study; one patient was not assessable for toxicity and response as therapy was prematurely interrupted on request of the patient who had not experienced toxicity. Thirty patients received a total of 59 courses. The dose-limiting toxicity (DLT) was reached at a dose of 0.6 mg/m2 twice daily and consisted of diarrhea, which started subacutely at a median onset on day 15 (range, 12 to 20) and resolved after a median of 8 days (range, 7 to 16). Other toxicities were mild, including leukocytopenia, thrombocytopenia, nausea, and vomiting. The MTD was 0.5 mg/m2 twice daily. No responses were observed. Pharmacokinetics showed a substantial variation of the area under the plasma concentration-time curve at time point "t" [AUC(t)] of topotecan and ring-opened product hydroxyacid. A significant correlation was observed between the percentage of decrease in WBC count versus the AUC(t) of topotecan (r = .75), which was modeled by a sigmoidal maximal effect concentration (Emax) function. CONCLUSION: The DLT in this phase I study for chronic oral topotecan for 21 days was diarrhea. The recommended dose for phase II studies is 0.5 mg/m2 twice daily.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias/tratamento farmacológico , Administração Oral , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/sangue , Camptotecina/farmacocinética , Diarreia/induzido quimicamente , Esquema de Medicação , Feminino , Meia-Vida , Humanos , Leucopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Trombocitopenia/induzido quimicamente , Topotecan
5.
J Clin Oncol ; 17(2): 685-96, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10080615

RESUMO

PURPOSE: We conducted a phase I dose-escalation trial of orally administered irinotecan (CPT-11) to characterize the maximum-tolerated dose (MTD), dose-limiting toxicities (DLTs), pharmacokinetic profile, and antitumor effects in patients with refractory malignancies. PATIENTS AND METHODS: CPT-11 solution for intravenous (IV) use was mixed with CranGrape juice (Ocean Spray, Lakeville-Middleboro, MA) and administered orally once per day for 5 days every 3 weeks to 28 patients. Starting dosages ranged from 20 to 100 mg/m2/d. RESULTS: Grade 4 delayed diarrhea was the DLT at the 80 mg/m2/d dosage in patients younger than 65 years of age and at the 66 mg/m2/d dosage in patients 65 or older. The other most clinically significant toxicity of oral CPT-11 was neutropenia. A linear relationship was found between dose, peak plasma concentration, and area under the concentration-time curve (AUC) for both CPT-11 and SN-38 lactone, implying no saturation in the conversion of irinotecan to SN-38. The mean metabolic ratio ([AUC(SN-38 total) + AUC(SN-38G total)]/AUC(CPT-11 total)) was 0.7 to 0.8, which suggests that oral dosing results in presystemic conversion of CPT-11 to SN-38. An average of 72% of SN-38 was maintained in the lactone form during the first 24 hours after drug administration. One patient with previously treated colorectal cancer and liver metastases who received oral CPT-11 at the 80 mg/m2/d dosage achieved a confirmed partial response. CONCLUSION: The MTD and recommended phase II dosage for oral CPT-11 is 66 mg/m2/d in patients younger than 65 years of age and 50 mg/m2/d in patients 65 or older, administered daily for 5 days every 3 weeks. The DLT of diarrhea is similar to that observed with IV administration of CPT-11. The biologic activity and favorable pharmacokinetic characteristics make oral administration of CPT-11 an attractive option for further clinical development.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/efeitos adversos , Camptotecina/efeitos adversos , Camptotecina/sangue , Camptotecina/farmacocinética , Camptotecina/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade
6.
J Clin Oncol ; 14(4): 1128-35, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8648367

RESUMO

PURPOSE: To evaluate irinotecan (CPT-11; Yakult Honsha, Tokyo, Japan) in patients with metastatic colorectal carcinoma that had recurred or progressed following fluorouracil (5-FU)-based therapy. PATIENTS AND METHODS: Patients were treated with irinotecan 125 to 150 mg/m2 intravenously (IV) every week for 4 weeks, followed by a 2-week rest. Forty-eight patients were entered onto the study and all were assessable for toxicity. Forty-three patients completed one full course of therapy and were assessable for response. RESULTS: One complete and nine partial responses were observed (response rate, 23%; 95% confidence interval [CI], 10% to 36%). The median response duration was 6 months (range, 2 to 13). The median survival time was 10.4 months and the 1-year survival rate was 46% (95% CI, 39% to 53%). Grade 4 diarrhea occurred in four of the first nine patients (44%) treated on this study at the 150-mg/m2 dose level. The study was amended to reduce the starting dose of irinotecan to 125 mg/m2. At this dose, nine of 39 patients (23%) developed grade 4 diarrhea. Aggressive administration of loperamide also reduced the incidence of grade 4 diarrhea. Grade 4 neutropenia occurred in eight of 48 patients (17%), but was associated with bacteremia and sepsis in only case. CONCLUSION: Irinotecan has significant single-agent activity against colorectal cancer that has progressed during or shortly after treatment with 5-FU-based chemotherapy. The incidence of severe diarrhea is reduced by using a starting dose of irinotecan 125 mg/m2 and by initiating loperamide at the earliest signs of diarrhea. These results warrant further clinical evaluation to define the role of irinotecan in the treatment of individuals with colorectal cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Terapia de Salvação , Adenocarcinoma/sangue , Adenocarcinoma/secundário , Antidiarreicos/uso terapêutico , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/efeitos adversos , Camptotecina/farmacocinética , Camptotecina/uso terapêutico , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Progressão da Doença , Esquema de Medicação , Resistencia a Medicamentos Antineoplásicos , Humanos , Infusões Intravenosas , Irinotecano , Loperamida/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
7.
Clin Cancer Res ; 6(3): 798-806, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10741699

RESUMO

An E1B 55 kDa gene-deleted adenovirus, Onyx-015, which reportedly selectively replicates in and lyses p53-deficient cells, was administered by a single intratumoral injection to a total of 22 patients with recurrent head and neck cancer. The objectives of this Phase I study were to determine the safety, feasibility, and efficacy of this therapy and determine any correlation to p53 status. Six cohorts were investigated with a dose escalation from 10(7)-10(11) plaque-forming units. Toxicity was assessed using NCIC criteria. Tumor response was assessed by clinical and radiological measurement. Blood samples were taken to detect adenovirus DNA and neutralizing antibody to adenovirus. Tumor biopsies were taken to detect adenovirus by in situ hybridization. Treatment was well tolerated, with the main toxicity being grade 1/2 flu-like symptoms. Dose-limiting toxicity was not reached at the highest dose of 10(11) plaque-forming units. Twenty-one of the 22 patients treated showed an increase in neutralizing antibody to adenovirus. In situ hybridization showed viral replication in 4 of 22 patients treated, all of whom had mutant p53 tumors. Using conventional response criteria, no objective responses were observed. However, magnetic resonance imaging scans were suggestive of tumor necrosis at the site of viral injection in five patients, three of whom were classified using nonconventional criteria as partial responders, and two of whom were classified using nonconventional criteria as minor responders. Of these five cases, four had mutant p53 tumors. The response duration for the three partial responders was 4, 8, and 12 weeks. An additional eight patients had stable disease in the injected tumors lasting from 4-8 weeks. These preliminary results show that intratumoral administration of Onyx-015 is feasible, well tolerated, and associated with biological activity. Further investigation of Onyx-015, particularly with a more frequent injection protocol and in combination with systemic chemotherapy, is warranted.


Assuntos
Proteínas E1B de Adenovirus/genética , Adenovírus Humanos/genética , DNA Viral/administração & dosagem , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Formação de Anticorpos , Efeito Citopatogênico Viral , DNA Viral/efeitos adversos , DNA Viral/genética , Vírus Defeituosos/genética , Feminino , Febre/etiologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Hibridização In Situ , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Mutação , Náusea/etiologia , Recidiva Local de Neoplasia , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética
8.
Clin Cancer Res ; 5(1): 69-75, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9918204

RESUMO

Prolonged exposure to topotecan in in vitro and in vivo experiments has yielded the highest antitumor efficacy. An oral formulation of topotecan with a bioavailability of 32-44% in humans enables convenient prolonged administration. Pharmacokinetic/pharmacodynamic relationships from four Phase I studies with different schedules of administration of oral topotecan in 99 adult patients with malignant solid tumors refractory to standard forms of chemotherapy were compared. Topotecan was administered as follows: (a) once daily (o.d.) for 5 days every 21 days (29 patients); (b) o.d. for 10 days every 21 days (19 patients); (c) twice daily (b.i.d.) for 10 days every 21 days (20 patients); and (d) b.i.d. for 21 days every 28 days (31 patients). Pharmacokinetic analysis was performed in 55 patients using a validated high-performance liquid chromatographic assay and noncompartmental pharmacokinetic methods. Totals of 109, 48, 64, and 59 courses were given, respectively. Dose-limiting toxicity consisted of granulocytopenia for the o.d. x 5-day dosage, a combination of myelosuppression and diarrhea in both of the 10-day schedules, and only diarrhea in the 21-day schedule. Pharmacokinetics revealed a substantial variation of the area under curve (AUC) of topotecan lactone in all of the dose schedules with a mean intrapatient variation of 25.4 +/- 31.0% (o.d. x 5), 34.5 +/- 25.0% (o.d. x 10), 96.5 +/- 70.1% (b.i.d. x 10), and 59.5 +/- 51.0% (b.i.d. x 21). Significant correlations were observed between myelotoxicity parameters and AUC(t) day 1 and AUC(t) per course of topotecan lactone. In all of the studies, similar sigmoidal relationships could be established between AUC(t) per course and the percentage decrease of WBCs. At maximum-tolerated dose level, no significant difference in AUC(t) per course was found [AUC(t) per course was 107.4 +/- 33.7 ng x h/ml (o.d. x 5), 145.3 +/- 23.8 ng x h/ml (o.d. x 10), 100.0 +/- 41.5 ng x h/ml (b.i.d. x 10), and 164.9 +/- 92.2 ng x h/ml (b.i.d. x 21), respectively.] For oral topotecan, the schedule rather than the AUC(t)-per-course seemed to be related to the type of toxicity. Prolonged oral administration resulted in intestinal side effects as a dose-limiting toxicity, and short-term administration resulted in granulocytopenia. On the basis of this pharmacokinetic study, no schedule preference could be expressed, but based on patient convenience, administration once daily for 5 days could be favored.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Topotecan/administração & dosagem , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Esquema de Medicação , Humanos , Leucopenia/induzido quimicamente , Pessoa de Meia-Idade , Neoplasias/metabolismo , Topotecan/efeitos adversos , Topotecan/farmacocinética
9.
Clin Cancer Res ; 5(2): 299-308, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10037178

RESUMO

A Phase I and pharmacological study was performed to evaluate the feasibility, maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), and pharmacokinetics of the anthrapyrazole losoxantrone in combination with paclitaxel in adult patients with advanced solid malignancies. Losoxantrone was administered as a 10-min infusion in combination with paclitaxel on either a 24- or 3-h schedule. The starting dose level was 40 mg/m2 losoxantrone and 135 mg/m2 paclitaxel (as a 24- or 3-h i.v. infusion) without granulocyte colony-stimulating factor (G-CSF). Administration of these agents at the starting dose level and dose escalation was feasible only with G-CSF support. The following dose levels (losoxantrone/paclitaxel, in mg/m2) of losoxantrone and paclitaxel as a 3-h infusion were also evaluated: 50/135, 50/175, 50/200, 50/225, and 60/225. The sequence-dependent toxicological and pharmacological effects of losoxantrone and paclitaxel on the 24- and 3-h schedules of paclitaxel were also assessed. The MTD was defined as the dose at which >50% of the patients experienced DLT during the first two courses of therapy. DLTs, mainly myelosuppression, occurring during the first course of therapy were noted in four of six and five of eight patients treated with 40 mg/m2 losoxantrone and 135 mg/m2 paclitaxel over 24 and 3 h, respectively, without G-CSF. DLTs during the first two courses of therapy were observed in one of six patients at the 50/175 (losoxantrone/paclitaxel) mg/m2 dose level, two of four patients at the 50/200 mg/m2 dose level, one of four patients at the 50/225 mg/m2 dose level, and two of five patients at the 60/225 mg/m2 dose level. The degree of thrombocytopenia was worse, albeit not statistically significant, when 24-h paclitaxel preceded losoxantrone, with a mean percentage decrement in platelet count during course 1 of 80.7%, compared to 43.8% with the reverse sequence (P = 0.19). Losoxantrone clearance was not significantly altered by the sequence or schedule of paclitaxel. Cardiac toxicity was observed; however, it was not related to total cumulative dose of losoxantrone. An unacceptably high rate of DLTs at the first dose level of 40 mg/m2 losoxantrone and 135 mg/m2 paclitaxel administered as either a 24- or 3-h i.v. infusion precluded dose escalation without G-CSF support. The addition of G-CSF to the regimen permitted further dose escalation without reaching the MTD. Losoxantrone at 50 mg/m2 followed by paclitaxel (3-h i.v. infusion) at 175 mg/m2 with G-CSF support is recommended for further clinical trials.


Assuntos
Antraquinonas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Paclitaxel/uso terapêutico , Pirazóis/uso terapêutico , Pirazolonas , Adulto , Idoso , Antraquinonas/efeitos adversos , Antraquinonas/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Relação Dose-Resposta a Droga , Estudos de Viabilidade , Seguimentos , Insuficiência Cardíaca/induzido quimicamente , Humanos , Terapia de Imunossupressão , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Neoplasias/metabolismo , Paclitaxel/efeitos adversos , Paclitaxel/farmacocinética , Pirazóis/efeitos adversos , Pirazóis/farmacocinética , Resultado do Tratamento
10.
Clin Cancer Res ; 4(5): 1153-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9607572

RESUMO

Prolonged exposure to topotecan (TPT) in in vitro experiments and in vivo studies in animals yielded the highest antitumor efficacy. An oral bioavailability of TPT of 32-44% enables convenient prolonged administration. Because of unpredictable diarrhea in the third week of the twice daily (b.i.d.) 21-day schedule of p.o. administered TPT and the finding of optimal down-regulation of topoisomerase I level after 10-14 days in mononuclear peripheral blood cells, a shorter period of administration (10 days) was chosen for Phase I and pharmacological studies of oral administration of TPT. Adult patients with malignant solid tumors that were refractory to standard forms of chemotherapy were entered. Two dose schedules were studied: once daily (o.d.) and b.i.d. administration for 10 days every 3 weeks. TPT o.d. for 10 days was studied at dose levels 1.0, 1.4, and 1.6 mg/m2/day, and dose levels were 0.5, 0.6, 0.7, and 0.8 mg/m2 with the 10-day b.i.d. schedule. Pharmacokinetics were performed on days 1 and 8 of the first course using a validated high-performance liquid chromatographic assay and noncompartmental pharmacokinetic methods. Nineteen patients were entered in the 10-day o.d. schedule, with a total of 48 courses given. Dose-limiting toxicity (DLT) was reached at 1.6 mg/m2/day and consisted of common toxicity criteria (CTC) grade IV thrombocytopenia and CTC grade III diarrhea. The maximum tolerated dose was 1.4 mg/m2/day. In the 10-day b.i.d. administration of TPT, a total of 64 courses were studied in 20 patients. DLT was reached at a dose of 0.8 mg/m2 b.i.d. and consisted of CTC grade IV myelosuppression and CTC grade IV diarrhea. The maximum tolerated dose was 0.7 mg/m2 b.i.d. Nonhematological toxicities with both schedules included mild nausea and vomiting, fatigue, and anorexia. Pharmacokinetics revealed a substantial variation of the area under the plasma concentration-time curve of TPT lactone in both schedules. Significant correlations were observed between the myelotoxicity parameters and the area under the plasma concentration-time curve at day 1 of TPT lactone o.d. and b.i.d. The DLT of 10 daily administrations of oral topotecan every 3 weeks consisted of a combination of myelosuppression and diarrhea for both schedules studied. The recommended doses for Phase II studies are 1.4 mg/m2/day for 10 days for the o.d. administration and 0.7 mg/m2 for the b.i.d. schedule.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Topotecan/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Esquema de Medicação , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Topotecan/administração & dosagem , Topotecan/efeitos adversos , Topotecan/farmacocinética
11.
Eur J Cancer ; 34(7): 1030-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9849451

RESUMO

Topotecan is a specific inhibitor to topoisomerase I. An oral formulation of topotecan is available with a bioavailability of 32-44% in humans. A phase I and pharmacological study of the oral formulation of topotecan administered daily for 5 days every 21 days was performed in adult patients with solid tumours to determine the maximum tolerated dose (MTD). Adult patients with a WHO performance status < or = 2 adequate haematological, hepatic and renal functions, with malignant solid tumours refractory to standard forms were entered into the study. Pharmacokinetics were performed on days 1 and 4 of the first course using a validated high performance liquid chromatographic assay. 29 patients entered the study, all patients were evaluable for toxicity and response. The doses studied in the 29 patients were 1.2, 1.8, 2.3, 2.7 mg/m2/day and a fixed dose of 4 mg/day without surface area adjustment. A total of 109 courses were given. Dose limiting toxicity (DLT) was reached at a dose of 2.7 mg/m2/day and consisted of CTC (NCI-Common Toxicity Criteria) grade IV granulocytopenia. The regimen was well tolerated. Non-haematological toxicities were mild, including fatigue, anorexia, nausea, vomiting and diarrhoea. A significant correlation was observed between the percentage decrease in white blood cells versus the area under the curve (AUC(t)) of topotecan lactone (R = 0.76 P < 0.01) which was modelled by a sigmoidal Emax function. The correlation coefficient between the absolute topotecan dose administered and the AUC(t) was R = 0.52 (P = 0.04). Pharmacokinetics of the fixed dose of 4 mg/day were comparable to the 2.3 mg/m2/day dose. DLT in this phase I study of five daily doses of oral topotecan every 21 days was granulocytopenia. The recommended dose for phase II studies is 2.3 mg/m2/day or alternatively, a fixed dose of 4 mg/day.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , Topotecan/administração & dosagem , Administração Oral , Adulto , Idoso , Anorexia/induzido quimicamente , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Fadiga/induzido quimicamente , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Topotecan/efeitos adversos , Topotecan/farmacocinética , Resultado do Tratamento
12.
Cancer Chemother Pharmacol ; 35(5): 397-402, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7850921

RESUMO

Preclinical studies of 2-chlorodeoxyadenosine (2-CdA) against solid tumors in the human tumor cloning assay and evidence that 2-CdA is active against slow-growing or resting tumor cells have stimulated interest in the clinical activity of this agent against solid tumors. This study sought to estimate the maximum tolerated dose, dose-limiting toxicity, and plasma and urine pharmacokinetics accompanying the intravenous administration of 2-CdA by 120-h continuous infusion in patients with solid tumors. Treated patients were also assessed for other toxicities of therapy and for antitumor response. A total of 23 patients received 35 courses of treatment given at doses of 3.5, 5.3, 6.5 and 8.1 mg/m2 per day by continuous intravenous infusion for 5 days and repeated every 28 days. Blood and urine specimens were collected before, during, and after drug infusion. The dose-limiting toxicity at 8.1 mg/m2 per day manifested as granulocytopenia in 2 of 5 patients (3 of 7 courses of treatment) and as thrombocytopenia in 3 of 5 patients (3 of 7 courses of treatment). At the dose levels of 6.5 and 8.1 mg/m2 per day, recovery from thrombocytopenia was often delayed. Severe lymphocytopenia (< 1,000/microliters) was observed at all dose levels of 2-CdA. Dose-related anemia and leukopenia were observed and were infrequently severe. Non-hematological toxicities were confined to mild-to-moderate nausea, vomiting, fatigue, and anorexia. Fever of 37 degrees-40 degrees C was induced during drug infusion in 19 patients. No antitumor response was observed. Average plasma concentrations at steady-state (Cpss) ranged from 3 ng/ml at the initial dose level to 13 ng/ml at the dose level of 8.1 mg/m2 per day. Both the Cpss and the area under the plasma concentration-time curve (AUC) were proportional to the dose. A relationship was observed between the percentage of change in absolute neutrophil count and the AUC. Renal excretion accounted for only 18% of the elimination of 2-CdA over the 5-day infusion period. The maximum tolerated dose for 2-CdA given by 5-day continuous infusion was 8.1 mg/m2 per day in this study. The recommended dose on this schedule for phase II studies is 6.5 mg/m2 per day. Granulocytopenia and thrombocytopenia were dose-limiting. No antitumor activity was observed during this study. On the basis of the plasma concentrations of 2-CdA observed, it is unlikely that this schedule of drug administration will permit achievement of the concentrations consistent with antitumor activity observed in preclinical studies.


Assuntos
Cladribina/efeitos adversos , Cladribina/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Agranulocitose/induzido quimicamente , Anemia/induzido quimicamente , Contagem de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cladribina/administração & dosagem , Cladribina/farmacocinética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Infusões Intravenosas , Linfopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Neutrófilos/efeitos dos fármacos , Trombocitopenia/induzido quimicamente
13.
Am J Clin Oncol ; 22(1): 78-81, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10025387

RESUMO

The authors evaluated the activity and toxicity of docetaxel given as a 1-hour infusion every 21 days in patients with unresectable cholangiocarcinoma. Seventeen patients with cytologically or histologically confirmed cholangiocarcinoma received intravenous docetaxel over 1 hour, repeated every 21 days. The initial dose of docetaxel was 100 mg/m2, with a subsequent 25% dose reduction for patients experiencing grade 3 or 4 toxicities. Treatment was continued until disease progression or occurrence of intolerable side effects. All patients received premedication with dexamethasone 8 mg by mouth twice daily for 5 days, starting 1 day before docetaxel infusion. Sixteen of the 17 patients were assessable for response and toxicity; one patient was removed from the trial for intercurrent illness. Thirty-eight cycles of docetaxel were delivered (median, two cycles). No complete or partial responses were noted. Fourteen patients had progressive disease, one patient had stable disease, and one patient died of septic shock shortly after starting treatment. Granulocytopenia was the dose-limiting toxicity. Thirteen patients had grade 4 granulocytopenia, 11 of whom required antibiotics for neutropenic fever. Granulocytopenia was the only grade 4 toxicity observed. Grade 3 toxicities included stomatitis, anemia, fatigue, vomiting, and hypotension. Grade 1 or 2 toxicities included alopecia, diarrhea, peripheral edema, myalgias, and anorexia. Administered on this dose and schedule, docetaxel lacked activity in patients with cholangiocarcinoma. The toxicity profile, including dose-limiting granulocytopenia, has been previously described in patients receiving docetaxel.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Paclitaxel/análogos & derivados , Taxoides , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Ductos Biliares Extra-Hepáticos , Ductos Biliares Intra-Hepáticos , Docetaxel , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Resultado do Tratamento
14.
Am J Clin Oncol ; 17(6): 498-501, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7977168

RESUMO

CONTEXT: Liposomal encapsulation of drugs can potentially ameliorate toxicities and improve acute and chronic tolerance. The increased uptake of liposomes by colon adenocarcinoma cell lines may enable DaunoXome to circumvent the p-glycoprotein-mediated anthracycline resistance of colon cancer cells. PURPOSE: To determine if DaunoXome, liposome-encapsulated daunorubicin, has clinical activity in patients with adenocarcinoma of the colon who failed treatment with a 5-fluorouracil containing regimen. METHOD: In a Phase II trial, patients with metastatic adenocarcinoma of the colon, whose disease has progressed after receiving one 5-fluorouracil-containing regimen, were treated with DaunoXome 100 mg/m2 repeated every 3 weeks. RESULTS: In this trial 16 patients received 45 courses of therapy. No objective tumor responses were seen. Hematologic toxicities consisted of neutropenia (grade 3 and 4), grade 2 anemia, and grade 2 thrombocytopenia. Nonhematologic toxicities were mild and manageable. Of the 16 patients, 5 experienced flushing, shortness of breath, chest tightness, and back pain during DaunoXome infusion, which resolved with infusion interruption, diphenhydramine, and meperidine. CONCLUSIONS: DaunoXome is generally well tolerated at a dose of 100 mg/m2 every 3 weeks. Toxicities are mild and reversible. On this schedule DaunoXome does not have significant clinical activity in patients with metastatic adenocarcinoma of the colon who have progressed after one 5-fluorouracil-containing regimen.


Assuntos
Adenocarcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Daunorrubicina/administração & dosagem , Adenocarcinoma/secundário , Adulto , Idoso , Daunorrubicina/uso terapêutico , Portadores de Fármacos , Feminino , Humanos , Lipossomos , Masculino , Pessoa de Meia-Idade , Indução de Remissão
15.
J Anim Sci ; 71(6): 1520-5, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8325812

RESUMO

To examine the effects of ingested snakeweed foliage (SW) on male fertility and reproduction, SW collected at prebloom stage was dried, ground, and mixed with ground commercial rat feed (CRF) as 0, 12.5, and 25% of total diets. Male rats fed SW for 20 d impregnated females as successfully as did dietary controls, but males fed 12.5 or 25% SW for 40 d had seemingly impaired fertility and apparently increased mortality of offspring. Males fed SW for an additional 30 and 42 d showed no differences (P > .05) in serum testosterone or LH concentrations after a GnRH challenge compared with controls. Semen samples collected from the vas deferens revealed that total sperm concentrations were similar (P > .10) between rats fed 12.5 or 25% SW and controls. The percentage of abnormal sperm was higher (P < .01) in rats fed 12.5 or 25% SW for 102 d, compared with the percentage of abnormal sperm in controls (11.5 and 17.8 vs 10.4%), and weight of testes was decreased (P < .05). Dietary SW increased (P < .01) activities of alkaline phosphatase and gamma-glutamyl transpeptidase over those in controls at d 20 (but not at d 98) and hepatomegaly was evident at d 50 and 98. Ingestion of snakeweed foliage by male rats increased abnormal sperm counts, impaired reproduction, and caused hepatotoxicosis.


Assuntos
Fertilidade , Intoxicação por Plantas/veterinária , Plantas Tóxicas , Reprodução , Sêmen , Animais , Análise Química do Sangue/veterinária , Feminino , Fertilização , Rim/anatomia & histologia , Fígado/anatomia & histologia , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Intoxicação por Plantas/sangue , Intoxicação por Plantas/fisiopatologia , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Testículo/anatomia & histologia , Testosterona/sangue
16.
Braz J Biol ; 73(1): 179-84, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23644800

RESUMO

The larvae of the southern beet webworm Herpetogramma bipunctalis (Fabricius, 1794) damage the leaves of species in the plant genus Rubus. The present study investigated the biology of H. bipunctalis and developed a protocol for raising H. bipunctalis under laboratory conditions. On the basis of the biological data, we devised a life table. In order to develop the rearing procedures, we determined which oviposition substrate and blackberry cultivar were the most appropriate for larval development. The mean durations of the egg, larval, and pupal stages were 5.59 days, 26.37 days, and 13.37 days, respectively, and the corresponding survival rates were 80.83%, 49.07%, and 83.23%. The mean pupal weight was 0.0491 g for males and 0.0536 g for females. The mean life cycle (egg-to-adult) period was 45.33 days, and overall survival to adulthood was 33.01%. H. bipunctalis females laid a mean of 252.63 eggs over a mean of 13.60 days of oviposition; the mean pre-oviposition period was 2.67 days. Mean female and male life spans were 17.51 and 19.25 days, respectively, and the sex ratio was 0.51. The life-table data indicated that H. bipunctalis can reproduce 57.9 times per generation. Each cage contained one blackberry leaf placed on a paper towel. This method allowed us to obtain the greatest number of eggs. The larval stage was shorter for insects reared on leaves of the Guarani cultivar than for those reared on leaves of the Xavante cultivar (22.63 vs. 26.37 days). These basic data can aid in establishing strategies for the management of H. bipunctalis on blackberry farms.


Assuntos
Lepidópteros/crescimento & desenvolvimento , Folhas de Planta/parasitologia , Rosaceae/parasitologia , Animais , Feminino , Lepidópteros/fisiologia , Estágios do Ciclo de Vida/fisiologia , Masculino , Oviposição/fisiologia , Reprodução/fisiologia , Razão de Masculinidade
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