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1.
Ann Oncol ; 24(10): 2554-2559, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23864097

RESUMO

BACKGROUND: There is an unmet need for predictive markers for the antiangiogenic agent bevacizumab in metastatic colorectal cancer (mCRC). We aimed to assess whether the location of the primary tumor is associated with bevacizumab effectiveness when combined with capecitabine and oxaliplatin (CAPEOX) in the first-line treatment of patients with mCRC. PATIENTS AND METHODS: A cohort of 667 consecutive patients with mCRC from the general community treated from 2006 to 2011 with CAPEOX and bevacizumab as standard first-line therapy was compared with a cohort of 213 patients treated with CAPEOX from 2003 to 2006, before bevacizumab was approved. Main outcome measures were progression-free survival (PFS) and overall survival (OS). Differences in outcome were tested using Kaplan-Meier curves and log-rank tests, and multivariate analyses were carried out using Cox Proportional Hazards models. RESULTS: Patients treated with CAPEOX and bevacizumab with primary tumors originating in the sigmoid colon and rectum had a significantly better outcome than patients with primary tumors originating from the cecum to the descending colon, both for PFS (median PFS 9.3 versus 7.2 months; hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.56-0.82) and for OS (median OS 23.5 versus 13.0 months; HR 0.47, 95% CI 0.38-0.57). This difference was confirmed in multivariate analyses after adjustment for other potentially prognostic factors. For patients treated with CAPEOX, there was no association between primary tumor location and outcome, neither in unadjusted nor adjusted analyses. CONCLUSIONS: The addition of bevacizumab to CAPEOX in first-line treatment of patients with mCRC may primarily benefit patients with primary tumors originating in the rectum and sigmoid colon. This hypothesis needs to be validated in data from completed randomized trials. CLINICALTRIALSGOV IDENTIFICATION NUMBER: NCT00212615.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Biomarcadores Tumorais/metabolismo , Capecitabina , Ceco/patologia , Colo Descendente/patologia , Colo Sigmoide/patologia , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Feminino , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/mortalidade , Reto/patologia , Neoplasias do Colo Sigmoide/tratamento farmacológico , Neoplasias do Colo Sigmoide/mortalidade , Sobrevida , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adulto Jovem
2.
Sci Total Environ ; 896: 165142, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37379909

RESUMO

Accessible populations of plants are critical to the meaningful exercise of Aboriginal and treaty rights in Canada. In the oil sands region of Alberta, populations of culturally significant plant species overlap with extensive oil and gas development. This has led to a host of questions and concerns related to plant health and integrity from both Indigenous communities and western scientists. Here, we assessed trace element concentrations in the northern pitcher-plant (tsala' t'ile; Sarracenia purpurea L.) with a focus on elements associated with fugitive dust and bitumen. Plant leaves were collected using clean methods and washed prior to analyses in an ultra-clean, metal-free laboratory. Pitcher-plant was an excellent model for assessing the impacts of industrial development on a culturally important, vulnerable species. Although concentrations of trace elements in pitcher-plant were low and not indicative of a toxicological concern, we saw clear dust signatures in plant tissues related to road and surface mine proximity. Elements associated with fugitive dust and bitumen extraction declined exponentially with increasing distance from a surface mine, a well-established regional pattern. However, our analyses also captured localized spikes in trace element concentrations within 300 m of unpaved roads. These local patterns are more poorly quantified at the regional scale but are indicative of the burden to Indigenous harvesters wishing to access plant populations that are not impacted by dust. Further work to directly quantify dust loads on culturally significant plants will help to define the amount of harvesting area lost to Indigenous communities due to dust impacts.


Assuntos
Sarraceniaceae , Oligoelementos , Poeira/análise , Alberta , Oligoelementos/análise , Campos de Petróleo e Gás , Monitoramento Ambiental/métodos
3.
Diabet Med ; 29(8): e184-90, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22268920

RESUMO

AIMS: Adding aldosterone receptor blockade to standard renoprotective treatment may provide additional renoprotection in patients with overt nephropathy. We expected an impact of spironolactone in early diabetic nephropathy, and for this hypothesis we studied the effect on markers of glomerular and tubular damage in patients with Type 1 diabetes and persistent microalbuminuria. METHODS: A double-blind, randomized, placebo-controlled crossover study in 21 patients with Type 1 diabetes and microalbuminuria using spironolactone 25 mg or placebo once daily, for 60 days added to standard antihypertensive treatment. After each treatment period, the primary endpoint were evaluated: urinary(u)-albumin excretion/24 hour(h) and secondary endpoints; 24 h blood pressure, glomerular filtration rate (GFR) and markers of tubular damage: urinary liver-type fatty-acid binding protein (LFABP), neutrophil gelatinase associated lipocalin (NGAL) and kidney injury molecule 1 (KIM1). RESULTS: All patients completed the study. During spironolactone treatment, urinary albumin excretion rate was reduced by 60% (range 21-80%), from 90 mg/24 h to 35 mg/24 h (P=0.01). Blood pressure (24 h) did not change during spironolactone treatment (P>0.2 for all comparisons). The GFR (SD) decreased from 78 (6) mL/min/1.73 m(2) to 72 (6) mL/min/1.73 m(2) (P=0.003). Urinary liver-type fatty-acid binding protein, neutrophil gelatinase-associated lipocalin and kidney injury molecule 1 did not change during treatment (P>0.3 for all comparisons). Treatment was well-tolerated, but two patients had severe hyperkalaemia (plasma potassium = 5.7 mmol/l), which was sufficiently treated with diuretics and dietary intervention. CONCLUSIONS: Spironolactone treatment in addition to standard renoprotective treatment lowers urinary albumin excretion in microalbuminuric patients with Type 1 diabetes, and thus may offer additional renoprotection independent of blood pressure.


Assuntos
Albuminúria/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Diuréticos/uso terapêutico , Espironolactona/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminúria/urina , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Estudos Cross-Over , Diabetes Mellitus Tipo 1/urina , Nefropatias Diabéticas/urina , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
Ann Oncol ; 22(2): 369-75, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20643864

RESUMO

BACKGROUND: The aim was to evaluate the association between plasma tissue inhibitor of metalloproteinase-1 (TIMP-1) and serum carcinoembryonic antigen (CEA) levels and outcome in patients with metastatic colorectal cancer (mCRC) receiving XELOX (combination chemotherapy with capecitabine and oxaliplatin) as first-line treatment. PATIENTS AND METHODS: One hundred and twenty patients were included. Blood samples were collected before treatment and 3 weeks later before the next treatment cycle. Plasma TIMP-1 and serum CEA levels were correlated to treatment outcome. RESULTS: No significant associations between baseline TIMP-1 or CEA levels and best response to treatment or progression-free survival (PFS) could be demonstrated. In contrast, high baseline plasma TIMP-1 levels were associated with poor overall survival (OS), P = 0.008, hazard ratio (HR) = 1.80 [95% confidence interval (CI): 1.17-2.78]. Furthermore, increase in TIMP-1 levels from baseline to immediately before the second cycle of chemotherapy had a significant negative effect on survival (P = 0.03, HR = 1.30, 95% CI: 1.02-1.65) while a decrease in TIMP-1 was significantly associated with a higher objective response rate (P = 0.03). CONCLUSIONS: Both high baseline and subsequent increase in TIMP-1 levels were associated with shorter OS in patients with mCRC receiving XELOX as first-line treatment, whereas baseline TIMP-1 levels were not associated with response or PFS following XELOX treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Inibidor Tecidual de Metaloproteinase-1/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Capecitabina , Neoplasias Colorretais/patologia , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Oxaloacetatos , Análise de Sobrevida , Resultado do Tratamento
5.
Ann Oncol ; 21(1): 87-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19622596

RESUMO

BACKGROUND: Chronotherapy is one of the several approaches to increase efficacy and reduce toxicity of chemotherapy. In a phase II study in the second-line in patients with metastatic colorectal cancer (mCRC), we found that chronomodulated XELOX (XELOX(30Chron)) was a well-tolerated regimen with potentially reduced toxicity. PATIENTS AND METHODS: One hundred and forty-one patients with unresectable mCRC were enrolled in a randomized study comparing standard XELOX (XELOX(30)), arm A, and XELOX(30Chron), arm B-both with short-time infusion of oxaliplatin-with the primary aim of reducing overall toxicity. RESULTS: Overall toxicity grade 2-4 was 90% versus 85%, P = 0.47 and grade 3-4 was 31% versus 37%, P = 0.6 in arm A and B, respectively. We found no significant differences in median overall survival (17.6 versus 15.5 months; P = 0.068) and median progression-free survival (8.9 versus 8.8 months; P = 0.7). The incidence of grade 3 neuropathy was 16% in arm A and 19% in arm B (P = 0.7) after a cumulative dose of oxaliplatin of 1000 mg/m(2). CONCLUSION: XELOX(30Chron) does not reduce toxicity or improve efficacy. A 30-min infusion of oxaliplatin is safe and does not increase the severity of chronic neuropathy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Cronofarmacoterapia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/análogos & derivados , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Oxaloacetatos
6.
Diabet Med ; 27(10): 1144-50, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20854382

RESUMO

AIMS: Our aim was to evaluate the markers of tubulointerstitial damage, neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule1 (KIM1) in Type 1 diabetic patients with different levels of albuminuria and in control subjects. In addition, the effect of renoprotective treatment on urinary NGAL was evaluated in diabetic nephropathy. METHODS: This was a cross-sectional study in 58 normoalbuminuric (u-albumin <30 mg/24 h), 45 microalbuminuric (30-300 mg/24 h) and 45 macroalbuminuric (>300 mg/24 h) Type 1 diabetic patients and 55 non-diabetic control subjects. Furthermore, in a second study, urine-NGAL was measured in a randomized cross-over study of 56 Type 1 diabetic patients with diabetic nephropathy treated with lisinopril 20, 40 and 60 mg daily. RESULTS: Urine-NGAL levels were [geometric mean (95% CI)]: control subjects 74 (52-104) (pg/mmol creatinine), normoalbuminuric 146 (97-221), microalbuminuric 222 (158-312) and macroalbuminuric group 261 (175-390). Urine-NGAL increased significantly from the normo- to the micro- and further to the macroalbuminuric group (P<0.05). Urine-NGAL was higher in normoalbuminuric vs. control subjects (P<0.01). Plasma-NGAL was significantly higher in the normoalbuminuric and macroalbuminuric groups than in the control group. Urine-KIM1 was higher in all diabetic groups than in the control group (P<0.001), with no difference between diabetic groups. During lisinopril treatment, urine-NGAL was reduced (95% CI) 17% (11-50) (not significant). CONCLUSIONS: Urine-NGAL and urine-KIM1 (u-KIM1) are elevated in Type1 diabetic patients, with or without albuminuria, indicating tubular damage at an early stage. Urine-NGAL increases significantly with increasing albuminuria. The ACE inhibitor lisinopril reduced urine-NGAL, but this was not statistically significant.


Assuntos
Proteínas de Fase Aguda/urina , Albuminúria/urina , Diabetes Mellitus Tipo 1/urina , Nefropatias Diabéticas/urina , Lipocalinas/urina , Lisinopril/uso terapêutico , Glicoproteínas de Membrana/urina , Proteínas Proto-Oncogênicas/urina , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Lipocalina-2 , Masculino , Glicoproteínas de Membrana/efeitos dos fármacos , Pessoa de Meia-Idade , Receptores Virais/efeitos dos fármacos
7.
Eur J Clin Nutr ; 59(3): 449-55, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15674304

RESUMO

OBJECTIVE: Some epidemiological studies found a lower risk of cardiovascular disease among wine drinkers than among drinkers of other types of ethanol. This difference might be due to an effect of nonalcohol compounds in wine on important cardiovascular risk factors. The objective of this study was to compare the effect of red wine, nonalcohol compounds of red wine and placebo on established cardiovascular risk factors. DESIGN: A parallel, four-armed intervention study. SUBJECTS: A total of 69 healthy 38-74-y-old men and women. INTERVENTIONS: Subjects were randomised to either 1: red wine (males: 300 ml/day, 38.3 g alcohol/day, female subjects: 200 ml/day, 25.5 g alcohol/day), 2: water + red grape extract tablets (wine-equivalent dose), 3: water + red grape extract tablets (half dose), or 4: water + placebo tablets for a period of 4 weeks. No other sources of alcohol or anthocyanin were allowed. Plasma high-density lipoprotein (HDL)-cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol (LDL-C), HDL-C/LDL-C-ratio, very-low-density lipoprotein (VLDL)-triacylglycerol, total cholesterol, fibrinogen, factor VII coagulant activity (FVIIc), blood pressure, and body weight were determined before and after intervention. RESULTS: Wine consumption was associated with a significant 11-16% increase in fasting HDL-C and 8-15% decrease in fasting fibrinogen relative to not drinking wine. There were no significant treatment effects on fasting LDL-C, HDL-C/LDL-C-ratio, VLDL-triacylglycerol, total cholesterol, FVIIc, or blood pressure. Drinking wine was associated with relative body weight increments closely corresponding to the energy contributed by the alcohol component. CONCLUSION: Moderate red wine consumption for 4 weeks is associated with desirable changes in HDL-C and fibrinogen compared with drinking water with or without red grape extract. The impact of wine on the measured cardiovascular risk factors thus seems primarily explained by an alcohol effect. Our finding suggests that the putative difference in cardiac risk associated with wine vs other alcoholic beverages might be rather explained by other life-style confounders than by red wine contents of nonalcohol components.


Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , HDL-Colesterol/sangue , Etanol/administração & dosagem , Hemostasia/fisiologia , Vinho , Adulto , Idoso , Colesterol/sangue , LDL-Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Fibrinogênio/análise , Fibrinogênio/metabolismo , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Aumento de Peso , Vinho/análise
8.
Clin Cancer Res ; 4(8): 1903-14, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9717818

RESUMO

Antibody-directed, superantigen-induced cytotoxicity has been shown to have potent in vitro and in vivo antitumor effects in preclinical models. In the present study, PNU-214565, a recombinant fusion protein consisting of the Fab of the monoclonal antibody C242 and staphylococcal enterotoxin A (SEA), was used in an escalating repeat dose Phase I clinical trial in patients with advanced gastrointestinal malignancies. A prior single-dose Phase I clinical trial had demonstrated safety at doses of 1.5 ng/kg with toxicities of fever and hypotension that were not dose related. Twenty-seven patients (age range, 36-75 years; median, 62; 14 males and 13 females; 23 colorectal and 4 pancreatic) were treated in the present study with one cycle of four consecutive daily 3-h infusions of PNU-214565 at doses of 0.15 ng/kg (n = 3); 0.5 ng/kg (n = 3), 1.5 ng/kg (n = 4), 2.75 ng/kg (n = 12), and 3.5 ng/kg (n = 5). All patients had a good performance status [Eastern Cooperative Oncology Group: PS = 0 (n = 15), PS = 1 (n = 12)]. As in the single-dose trial, fever and hypotension were the most common toxicities. Dose-limiting toxicity (DLT), consisting of transient hypotension responsive to dopamine, was experienced by one patient treated at the 2.75 ng/kg dose level. One patient with pancreatic cancer metastatic to the liver experienced a partial response of hepatic metastases with stable pancreatic head abnormalities by computed tomography scan. Further dose escalation was suspended when two patients treated in a companion repeat dose Phase I study experienced DLT at the 4 ng/kg dose level. Multiparameter analyses on all patients treated in the two companion single-dose and two-repeated-dose Phase I trials revealed that the levels of patients' pretreatment anti-SEA antibodies protected against toxicity at a given drug dose. By jointly considering weight and the baseline anti-SEA concentration in a patient, it is possible to assign a PNU-214565 dose that will induce systemic cytokine release (a surrogate test to assess for the presence of uncomplexed drug and its ability to induce systemic cellular activation) without DLT. This pharmacodynamically based dosing scheme will be tested in future repeated-dose clinical trials and will define maximally tolerated doses of this powerful new immunotherapy approach.


Assuntos
Enterotoxinas/uso terapêutico , Neoplasias Gastrointestinais/tratamento farmacológico , Fragmentos de Imunoglobulinas/uso terapêutico , Imunotoxinas/uso terapêutico , Indutores de Interferon/uso terapêutico , Superantígenos/imunologia , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Enterotoxinas/efeitos adversos , Feminino , Neoplasias Gastrointestinais/imunologia , Humanos , Fragmentos de Imunoglobulinas/efeitos adversos , Imunotoxinas/efeitos adversos , Infusões Intravenosas , Indutores de Interferon/efeitos adversos , Masculino , Pessoa de Meia-Idade
9.
Am J Clin Nutr ; 69(1): 87-94, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9925128

RESUMO

BACKGROUND: Epidemiologic studies suggest that foods rich in flavonoids might reduce the risk of cardiovascular disease. OBJECTIVE: Our objective was to investigate the effect of intake of flavonoid-containing black currant and apple juice on urinary excretion of quercetin and on markers of oxidative status. DESIGN: This was a crossover study with 3 doses of juice (750, 1000, and 1500 mL) consumed for 1 wk by 4 women and 1 man corresponding to an intake of 4.8, 6.4, and 9.6 mg quercetin/d. RESULTS: Urinary excretion of quercetin increased significantly with dose and with time. The fraction excreted in urine was 0.29-0.47%. Plasma quercetin did not change with juice intervention. Plasma ascorbate increased during intervention because of the ascorbate in the juice. Total plasma malondialdehyde decreased with time during the 1500-mL juice intervention, indicating reduced lipid oxidation in plasma. Plasma 2-amino-adipic semialdehyde residues increased with time and dose, indicating a prooxidant effect of the juice, whereas erythrocyte 2-aminoadipic semialdehyde and gamma-glutamyl semialdehyde concentrations, Trolox-equivalent antioxidant capacity, and ferric reducing ability of plasma did not change. Glutathione peroxidase activity increased significantly with juice dose. CONCLUSIONS: Urinary excretion of quercetin seemed to be a small but constant function of quercetin intake. Short-term, high intake of black currant and apple juices had a prooxidant effect on plasma proteins and increased glutathione peroxidase activity, whereas lipid oxidation in plasma seemed to decrease. These effects might be related to several components of the juice and cannot be attributed solely to its quercetin content.


Assuntos
Antioxidantes/metabolismo , Bebidas , Dieta , Frutas , Quercetina/administração & dosagem , Quercetina/urina , Adulto , Ácido Ascórbico/sangue , Biomarcadores/sangue , Estudos Cross-Over , Feminino , Humanos , Masculino , Malondialdeído/sangue , Quercetina/sangue
10.
J Immunol Methods ; 119(2): 203-10, 1989 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-2470825

RESUMO

The tetrazolium salt (MTT) method involving conversion of MTT to coloured formazan by cells serving as indirect measurements of cell growth/cell kill has been reported by several groups, although technical problems have been encountered. The present investigation was undertaken in order to delineate what laboratory variables have direct influence on the sensitivity and reproducibility of the method. The pH of the extraction buffer was of the utmost importance, since it was demonstrated that a pH greater than 5 would give rise to false signals. Furthermore, modifying the composition of the extraction buffer, all formazan dye grains were solubilised, totally. A direct comparison with published methods demonstrated that only the modified method would yield 100% higher signals without increasing the background. In contrast to previous reports, it was shown that phenol red does not interfere with the measurements and no washing steps are required since all ingredients can be added subsequently. Serum proteins at concentrations up to 25% have no influence on the result. All samples can be measured in an ELISA scanner at 570 nm with little intra-assay variation.


Assuntos
Divisão Celular , Sobrevivência Celular , Coloração e Rotulagem , Sais de Tetrazólio , Tiazóis , Células Tumorais Cultivadas/patologia , Animais , Soluções Tampão , Contagem de Células , Linhagem Celular , Corantes , Formazans , Concentração de Íons de Hidrogênio , Cinética , Camundongos , Reprodutibilidade dos Testes , Espectrofotometria , Coloração e Rotulagem/métodos , Células Tumorais Cultivadas/metabolismo
11.
Leuk Res ; 19(7): 443-7, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7637389

RESUMO

Deoxycytidine kinase (dCK) is important in the 5'-phosphorylation of deoxynucleoside analogs. Like dCK, thymidine kinase 2 (TK2) catalyzes the initial step of the phosphorylation of dcyd to dCTP. Thymidine is a strong inhibitor of the dCK activity of TK2. We examined the ratio of the dcyd phosphorylation carried out by dCK and by TK2 (dCK/TK2-dcyd) in lymphocytes from CLL patients and from donors. In the CLL lymphocytes we found a 3.5-fold average increase. Therefore, we conclude that addition of thymidine in the treatment of CLL with deoxynucleoside analogs will not be of any advantage. Furthermore, our results can explain earlier findings in CML and AML lymphocytes where the ara-C phosphorylation was twice the dcyd phosphorylation.


Assuntos
Desoxicitidina Quinase/metabolismo , Leucemia Linfocítica Crônica de Células B/enzimologia , Linfócitos/enzimologia , Timidina Quinase/metabolismo , Células Cultivadas , Cladribina/metabolismo , Humanos , Fosforilação , Especificidade por Substrato , Células Tumorais Cultivadas
12.
APMIS ; 98(2): 156-62, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1689165

RESUMO

A biological method for precise quantification of interferons has been developed. The method is based upon the dehydrogenase system of the intact target cells, which will normally convert an artificial substrate, MTT, into formazan (blue), which, in turn, can be measured spectrophotometrically. This conversion is greatly reduced by cytocidal viruses in a dose-dependent manner. The protection of target cells by interferon against challenge virus is reflected in a diminished reduction in the production of formazan, thus giving a very precise method for quantification of interferon. The lowest level of detection is around 0.10 international units. The intra- and inter-assay variability appear to be below 10%. The assay, which makes no use of expensive ingredients, is performed in 96-well micro-trays and read in an inexpensive ELISA-scanner.


Assuntos
Bioensaio/métodos , Interferons/análise , Mitocôndrias/enzimologia , Oxirredutases/análise , Linhagem Celular , Efeito Citopatogênico Viral , Espectrofotometria , Viroses/enzimologia
13.
Intensive Care Med ; 29(4): 642-5, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12552364

RESUMO

OBJECTIVE: Superoxide (O(2)(-)), a key antimicrobial agent in phagocytes, is produced by the activity of NADPH oxidase. High glucose concentrations may, however, impair the production of O(2)(-) through inhibition of glucose-6-phosphate dehydrogenase (G6PD), which catalyzes the formation of NADPH. This study measured the acute effects of high glucose or the G6PD inhibitor dehydroepiandrosterone (DHEA) on the production of O(2)(-) from isolated human neutrophils. DESIGN: Laboratory studies of short-term cultures of neutrophil granulocytes. PARTICIPANTS: Healthy subjects. INTERVENTIONS: Neutrophils were isolated from peripheral blood and incubated for 1 h in Krebs-Ringer buffer containing 5, 10, or 25 mM glucose, 5 mM glucose with 0, 5, or 20 mM mannitol, or 5 mM glucose with 0, 1, 10, or 100 micro M DHEA. O(2)(-) production was induced by N-formyl-methionyl-leucyl-phenylalanine and measured by the cytochrome c reduction assay. Potential scavenging of O(2)(-) by glucose, mannitol, or DHEA was assessed in a cell free system using the pyrogallol assay. MEASUREMENTS AND RESULTS: Incubation of neutrophils with glucose dose-dependently reduced O(2)(-) production, which was 50% decreased at 25 mM glucose. Also DHEA reduced the production of O(2)(-) dose-dependently, whereas production rates were unaffected by mannitol. Neither glucose, mannitol, nor DHEA scavenged O(2)(-). CONCLUSIONS: High extracellular glucose concentrations acutely reduce O(2)(-) production from activated neutrophils possibly through inhibition of G6PD. If this occurs in vivo, microbial killing by neutrophils may be impaired during acute hyperglycemia, as observed after major surgery, trauma, or severe infection.


Assuntos
Desidroepiandrosterona/farmacologia , Glucose/farmacologia , Neutrófilos/metabolismo , Superóxidos/metabolismo , Análise de Variância , Células Cultivadas , Humanos , Neutrófilos/efeitos dos fármacos
14.
Phytochemistry ; 39(3): 625-30, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7576453

RESUMO

Investigation of the ethanolic extracts from Phytolacca rivinoides and P. bogotensis has resulted in the isolation of five new triterpenoid glycosides of serjanic acid. Their structures have been established mainly by spectroscopic methods (FAB-MS, 1H, 13C NMR, COSY, NOESY, TOCSY, HETCOR and J-resolved 1H NMR) as 3-O-(O-beta-D-galactopyranosyl-(1-->3)-O-beta-D-glucopyranosyl)serjan ic acid 28-O-beta-D-glucopyranosyl ester, 3-O-(O-beta-D-glucopyranosyl-(1-->3)-O-[beta-D-galactopyranosyl-(1-->4)] -O- beta-D-glucopyranosyl)serjanic acid 28-O-beta-D-glucopyranosyl ester, 3-O-(O-alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->2)- O-beta-glucopyranosyl)serjanic acid 28-O-beta-D-glucopyranosyl ester, 3-O-(O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-galactopyranosyl-(1-->4)- O-beta-D-glucopyranosyl)serjanic acid 28-O-beta-D-glucopyranosyl ester and 3-O-(O-beta-D-galactopyranosyl-(1-->4)-O-[beta-D-glucopyranosyl-(1-->3)] - O-beta-D-glucopyranosyl)serjanic acid.


Assuntos
Plantas Medicinais/química , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Saponinas/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Triterpenos/química
15.
Food Chem Toxicol ; 38(9): 739-46, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10930694

RESUMO

The present study was carried out in order to investigate the in vivo biotransformation and excretion of the flavone, tangeretin, found in citrus fruits, by analysing urine and faeces samples from rats after repeated administration of 100 mg/kg body weight/day tangeretin. The formed metabolites were separated and identified by HPLC and the structures elucidated by LC/MS and 1H NMR. Ten new, major metabolites with intact flavonoid structure were identified. The metabolites identified were either demethylated or hydroxylated derivatives of the parent compound and metabolic changes were found primarily to occur in the 4' position of the B-ring. The total urinary excretion of tangeretin metabolites with intact flavan nucleus was about 11% of the administered daily dose.


Assuntos
Citrus/química , Flavonas , Flavonoides/farmacocinética , Animais , Biotransformação , Fezes/química , Feminino , Flavonoides/química , Flavonoides/urina , Estrutura Molecular , Ratos , Ratos Wistar
16.
Food Chem Toxicol ; 40(5): 609-16, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11955666

RESUMO

Human and mouse liver microsomes and membranes isolated from Escherichia coli, which expressed cytochrome P450 (CYP) 1A2, 3A4, 2C9 or 2D6, were used to investigate CYP-mediated metabolism of five selected dietary flavonoids. In human and mouse liver microsomes kaempferol, apigenin and naringenin were hydroxylated at the 3'-position to yield their corresponding analogs quercetin, luteolin and eriodictyol, whereas hesperetin and tamarixetin were demethylated at the 4'-position to yield eriodictyol and quercetin, respectively. Microsomal flavonoid metabolism was potently inhibited by the CYP1A2 inhibitors, fluvoxamine and -naphthoflavone. Recombinant CYP1A2 was capable of metabolizing all five investigated flavonoids. CYP3A4 recombinant protein did not catalyze hesperetin demethylation, but showed similar metabolic profiles for the remaining compounds, as did human microsomes and recombinant CYP1A2, although the reaction rates in general were lower as compared to CYP1A2. CYP2C9 catalyzed the 4'-demethylation of tamarixetin, whereas CYP2D6 did not seem to play any role in the metabolism of the selected flavonoids. The major involvement in flavonoid metabolism of human CYP1A2, which mediates the formation of metabolites with different biochemical properties as compared to the parent compound and furthermore is known to be expressed very differently among individuals, raises the important question of whether individual differences in the CYP enzyme activity might affect the beneficial outcome of dietary flavonoids, rendering some individuals more or less refractory to the health-promoting potential of dietary flavonoids.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Flavonoides/metabolismo , Animais , Biotransformação , Inibidores das Enzimas do Citocromo P-450 , Dieta , Inibidores Enzimáticos/farmacologia , Feminino , Análise de Alimentos , Humanos , Técnicas In Vitro , Cinética , Membranas/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/enzimologia , Proteínas Recombinantes/metabolismo , Especificidade da Espécie
17.
Ugeskr Laeger ; 159(21): 3134-9, 1997 May 19.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9198999

RESUMO

This article reviews the treatment of colorectal carcinoma with monoclonal antibodies. Since the late seventies, several hundred patients with advanced disease have been treated with unconjugated antibodies, especially Mab 17-1A. The response rate of the studies has been less than 10%. In contrast, Mab given as adjuvant treatment for Duke's C colorectal carcinoma increased the five year survival with 30%. The actions of different types of immunoconjugates are reviewed.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias do Colo/terapia , Neoplasias Retais/terapia , Neoplasias do Colo/imunologia , Humanos , Neoplasias Retais/imunologia
18.
Ugeskr Laeger ; 155(35): 2676-8, 1993 Aug 30.
Artigo em Dinamarquês | MEDLINE | ID: mdl-8212380

RESUMO

Two cases of infection with multiply resistant Salmonella virchow were probably acquired in Denmark. A 30-year old man and a 20-year old woman had both eaten from the same buffet at a summer restaurant and developed gastrointestinal symptoms and fever after three and six days, respectively. The patients ran a fever for two and five weeks before the admission to the hospital and the woman developed a tuboovarial abscess complicated by peritonitis. S. virchow resistant to ampicillin, streptomycin, tetracycline, and sulfonamide was isolated from faeces in the male patient and from intraabdominal pus in the female patient. Among 35 Danish S. virchow isolates from January 1 to August 31, 1992 there was only one additional multiply resistant isolate (resistant to streptomycin, tetracycline, sulfonamide, and chloramphenicol) the source of which was unknown.


Assuntos
Intoxicação Alimentar por Salmonella/microbiologia , Salmonella/classificação , Adulto , Dinamarca , Resistência Microbiana a Medicamentos , Feminino , Humanos , Masculino , Salmonella/imunologia , Salmonella/isolamento & purificação , Intoxicação Alimentar por Salmonella/tratamento farmacológico
19.
Ugeskr Laeger ; 157(16): 2325-6, 1995 Apr 17.
Artigo em Dinamarquês | MEDLINE | ID: mdl-7652972

RESUMO

A case of cholera imported to Denmark from the Pacific is presented. The patient was successfully treated with rehydration and antibiotics. A survey of the ongoing seventh pandemic of cholera is given and the possible emergence of a new eighth pandemic is discussed. Guidelines for prophylactic and therapeutic measures are discussed. Although V. cholerae colonies can be recognized on routine cultivation media, low numbers require selective media, and this is not included in routine investigations of stools for pathogens.


Assuntos
Cólera , Viagem , Cólera/diagnóstico , Cólera/tratamento farmacológico , Cólera/etiologia , Ciprofloxacina/administração & dosagem , Dinamarca , Feminino , Humanos , Pessoa de Meia-Idade , Ilhas do Pacífico/epidemiologia
20.
Ugeskr Laeger ; 160(4): 429-33, 1998 Jan 19.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9463256

RESUMO

Denmark has in recent years experienced a rise in the number of bacterial gastrointestinal infections. We have reviewed patients hospitalized with culture confirmed bacterial gastroenteritis in Roskilde County during 1991-1993. Two hundred and seven patients were included, 68 were children (< 15 years). The microorganism isolated was Salmonella in 61% of the cases. Campylobacter in 20% and Yersinia enterocolitica in 13%. Ninety-three percent of the patients had diarrhoea, 74% had fever (> 38 degrees C), and 66% abdominal pain. Blood in the stools was most frequent in patients infected with Campylobacter. Leucocytosis was rare. Twenty-four patients had bacteraemia. Reactive arthritis occurred in 4.8%. Three patients died, all infected with zoonotic Salmonella types. Three stool cultures were made for 115 patients, and all three cultures were positive in 73% of these patients. Bacterial gastroenteritis requiring hospitalization in Roskilde County, 1991-1993 affected mainly children and young adults. Infections due to zoonotic Salmonella types were more severe than Campylobacter and Yersinia enterocolitica gastroenteritis. It seems necessary to collect at least three stool cultures to secure a bacteriological diagnosis.


Assuntos
Gastroenterite/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Gastroenterite/microbiologia , Hospitalização , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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