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1.
Environ Pollut ; 121(2): 239-52, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12521111

RESUMO

Regional variation in PCBs and organochlorine (OC) pesticide concentrations was examined using the blubber of 155 minke whales (Balaenoptera acutorostrata) sampled in seven regions in the North Atlantic and European Arctic, including western and southeastern Greenland, the Norwegian Sea, the North Sea and the Barents Sea. The levels and relative proportions of OCs were also used to examine the boundaries for North Atlantic minke whale stocks previously defined by the International Whaling Commission (IWC). Concentrations of major OC groups (sigmaPCB, 89.1-22 800 ng/g lipid; sigmaDDT, 65.3-6280 ng/g lipid; sigmaCHL, 33.3-2110 ng/g lipid) generally increased from west to east, while HCH concentrations (sigmaHCH, < 1-497 ng/g lipid) showed the opposite trend. Statistical comparison between six regions using sex-adjusted least squared mean concentrations showed that minke whales from the Barents Sea had significantly higher concentrations of EPCBs than those from the Vestfjorden/Lofoten, the North Sea, and west Svalbard, as well as significantly higher sigmaDDT concentrations compared to west Greenland animals. The differences in concentrations suggest that west and southeast Greenland minkes may represent one group of whales, which are distinct from both the Jan Mayen minkes and those from other IWC defined stocks in northern European waters. Principal components analysis using proportions of 71 PCB congeners and 20 OC pesticides (of total OCs) did not reveal any major differences among groups although minkes from the North Sea were distinguished from those from Greenland waters by higher loadings of more highly chlorinated PCBs and recalcitrant OC pesticides. The general similarity in mean levels of sigmaPCBs, sigmaDDT and sigmaCHL, as well as mean principal components analysis scores, among minkes sampled at Jan Mayen, Svalbard, Vestfjorden/Lofoten, the North Sea and the Barents Sea suggests that the whales are quite mobile and may feed in multiple areas within the northeastern Atlantic.


Assuntos
Inseticidas/análise , Poluentes Químicos da Água/análise , Baleias/metabolismo , Análise de Variância , Animais , Regiões Árticas , Oceano Atlântico , Feminino , Masculino , Bifenilos Policlorados/análise , Maturidade Sexual
2.
Environ Pollut ; 114(2): 243-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11504347

RESUMO

Concentrations of PCB congeners and organochlorine (OC) pesticides were studied in archived fin whale (Balaenoptera physalus) blubber samples collected in 1971-1972 from Newfoundland (Nfld) and Nova Scotia (NS) with the objective of obtaining a historical perspective on contaminant levels and proportions at a time when many persistent OCs were still in use. Concentrations of sigmaPCBs and sigmaDDTs in the blubber of 17 fin whales from historical whaling stations in 1971-1972 were generally in agreement with previously reported values for fin whales from Atlantic Canada. Although some differences in sex and body length (age) distribution of samples occurred, significant differences were detected in the concentrations and patterns of PCBs, DDTs and chlordanes in whales from Nfld and NS, supporting ecological evidence that whales from these regions represent relatively separate stocks. Temporal and geographical variations were examined by comparing data to those reported for fin whales from the St Lawrence Estuary (StL) in 1991 by Gauthier et al. (1997a). Significantly higher levels of sigmaDDT, sigmaCHL and HCB were found in the NS (1971-1972) stock compared with the StL (1991) animals, and in HCB between the Nfld stock (1971-1972) and the StL (1991) animals, as well as higher p,p'-DDE/sigmaDDT and lower p,p'-DDT/sigmaDDT ratios in the 1991 whales suggesting that temporal trends in these whales between the 1970s and 1990s were consistent with those in other marine mammals in Atlantic Canada. Evidence also suggests that geographical variations in patterns may occur for individuals from two relatively distinct stocks of fin whales in Atlantic Canada (NS, Nfld) and perhaps for one population (StL) related to, but recognisably different from the NS stock.


Assuntos
Poluentes Ambientais/farmacocinética , Bifenilos Policlorados/farmacocinética , Poluentes Químicos da Água/farmacocinética , Baleias/fisiologia , Tecido Adiposo/química , Animais , Canadá , Exposição Ambiental , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Geografia , Masculino , Bifenilos Policlorados/análise , Bifenilos Policlorados/química , Dinâmica Populacional , Fatores de Tempo , Distribuição Tecidual , Poluentes Químicos da Água/análise
3.
Br J Cancer ; 79(11-12): 1665-71, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10206275

RESUMO

Intra-arterial Lipiodol has been used to deliver targeted therapies to primary, and some metastatic, liver cancers. Targeted radiotherapy has been used by substituting the iodine in Lipiodol with 131Iodine (131I). Early clinical results are encouraging, but the variable response may partly depend on local pharmacokinetics. This study evaluated the in vitro cytotoxic effects of 131I-Lipiodol on human hepatocellular carcinoma (Hep-G2), human colorectal metastatic cancer (SW620), human colorectal hepatic cancer (LoVo) and human umbilical vein endothelial cells (HUVEC) cell lines. The cell cultures were exposed to 131I-Lipiodol for 48 h, following which cell counts and viability were assessed by haemocytometer, S-Rhodamine uptake and radioactivity assay. The effect of exposure to control Lipiodol, 131I-Lipiodol and 131I alone was evaluated. 131I-Lipiodol was cytotoxic against all the cancer cell lines but not against the non-malignant (HUVEC) cell line. The cytotoxicity effects were very similar in all the cancer cell lines. There were no cytotoxic effects following exposure to plain 131I in any of the cell lines (malignant and non-malignant). A similar trend was seen with radioactivity counts using a gamma counter. The cytotoxic effect of 131I-Lipiodol had a graded effect with an increase in cytotoxicity following the increase in the radioactive dose. This study showed that there was a marked cytotoxic effect by 131I-Lipiodol on all the cancer cell lines. There was no difference between the controls and the 131Iodine. This suggests that effective 131I-Lipiodol targeted therapy is dependent on the uptake and retention of Lipiodol by malignant cells.


Assuntos
Neoplasias Colorretais/radioterapia , Óleo Iodado , Neoplasias Hepáticas/radioterapia , Divisão Celular/efeitos da radiação , Linhagem Celular , Meios de Contraste , Estudos de Avaliação como Assunto , Humanos , Radioterapia/métodos , Rodaminas , Células Tumorais Cultivadas
4.
Pediatrics ; 101(3 Pt 2): 549-54, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12224661

RESUMO

Physical activity is a key component of energy balance and is promoted in children and adolescents as a lifelong positive health behavior. Understanding the potential behavioral determinants necessitates understanding influences from three fundamental areas: 1) physiologic and developmental factors, 2) environmental factors, and 3) psychological, social, and demographic factors. The literature to date has generally investigated potential predictors of physical activity in children and adolescents in each of these three general areas, although existing data rely largely on cross-sectional studies in which it is difficult to distinguish a determinant from a correlate. In all likelihood, aspects of each of these three areas interact in a multidimensional way to influence physical activity in youth. This article reviews evidence of potential determinants of physical activity in children and adolescents and provides recommendations for future work.


Assuntos
Comportamento do Adolescente/fisiologia , Comportamento Infantil/fisiologia , Desenvolvimento Infantil/fisiologia , Esforço Físico/fisiologia , Adolescente , Fatores Etários , Criança , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Probabilidade , Meio Social
6.
Br J Cancer ; 73(7): 877-81, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8611399

RESUMO

Iodised oil (lipiodol) administered via the hepatic artery localises selectively in primary liver cell cancers (hepatocellular carcinomas or HCCs) for prolonged periods and has been used as a vehicle for cytotoxic agents. Despite clinical use, the mechanism of lipiodol retention by tumours has remained unclear, embolisation of oil droplets in the tumour vasculature being the prevailing hypothesis. We have investigated the role of tumour and endothelial cells in lipiodol retention. Human liver tumour (Hep G2) cells and human umbilical vein endothelial cells in culture were exposed to lipiodol. Light microscopy using selective silver impregnation stains and transmission electron microscopy revealed lipiodol incorporation by both cell types, probably by pinocytosis. This was not associated with cellular injury in terms of cell lysis, cell replication or radio-labelled leucine uptake. Histological analysis of 24 HCCs either surgically resected or discovered incidentally at liver transplantation (with prior arterial injection of lipiodol) revealed vesicles of lipiodol in the cytoplasm of tumour cells and endothelial cells lining tumour vessels. Thus, lipiodol is likely to deliver cytotoxic agents directly into tumour cells and endothelial cells, both in vitro and in vivo. This may also apply to other lipids and to other human tumours. These findings have significant therapeutic implications.


Assuntos
Carcinoma Hepatocelular/metabolismo , Meios de Contraste/farmacocinética , Endotélio Vascular/metabolismo , Óleo Iodado/farmacocinética , Neoplasias Hepáticas/metabolismo , Células Cultivadas , Meios de Contraste/metabolismo , Meios de Contraste/farmacologia , Humanos , Óleo Iodado/metabolismo , Óleo Iodado/farmacologia , Células Tumorais Cultivadas
7.
Cancer ; 76(11): 2202-10, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8635022

RESUMO

BACKGROUND: Arterially administered iodized oil (Lipiodol) is selectively retained by hepatocellular carcinomas (HCCs), and has been used as a vehicle for delivery of therapeutic agents to these tumors. This study compared the efficacy of Lipiodol-targeted epirubicin chemotherapy with Lipiodol-131I radiotherapy. METHODS: Ninety-five patients with unresectable HCC confined to the liver were administered either Lipiodol-epirubicin emulsion (n = 69; 61 cirrhotics; Okuda tumor Stage I, 14; II, 37; III, 18; epirubicin dose, 75 mg/m2) or Lipiodol-131I (131I) (n = 26; 18 cirrhotics; Okuda tumor Stage I, 6; II, 19; III, 1; dose 750-1050 MBq). The last 28 patients (17 epirubicin, 11 131I) were treated within a prospective randomized trial. Bolus drug or isotope was injected into the hepatic artery by transfemoral cannulation. Lipiodol and 131I uptake were gauged by 10th day computed tomography and 48-hour scintiscan. Treatments were repeated two-monthly when indicated. RESULTS: Tumor size at 2 months remained static or diminished partially in 21 of 38 epirubicin recipients (55%) and 15/22 131I recipients (68%). Actuarial survival at 6, 12, and 24 months was 40%, 25%, and 6% with epirubicin, and 58%, 25%, and 0% with 131I; 30-day mortality was 11% and 15%, respectively. Comparison with historic controls indicated survival benefit in Stages I and II. Similar findings were recorded in the 28 patients in the randomized trial. CONCLUSIONS: Patients with unresectable HCC receiving Lipiodol-epirubicin or Lipiodol-131I show good tumor localization, acceptable toxicity, and comparable survival benefit at 6 and 12 months with either modality.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Epirubicina/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/radioterapia , Análise Atuarial , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Estudos de Casos e Controles , Cateterismo Periférico , Meios de Contraste , Epirubicina/administração & dosagem , Feminino , Artéria Femoral , Seguimentos , Artéria Hepática , Humanos , Injeções Intra-Arteriais , Radioisótopos do Iodo/administração & dosagem , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Veículos Farmacêuticos , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida
9.
BMJ ; 311(7001): 392-3, 1995 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-7640567
10.
HPB Surg ; 8(3): 163-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7547618

RESUMO

Hepatocellular carcinoma arising in a patient with genetic haemachromatosis, without cirrhosis, has only been described once previously. We present a patient with a 15 year history of genetic haemachromatosis who underwent resection of a hepatocellular carcinoma in a liver with normal architecture.


Assuntos
Carcinoma Hepatocelular/etiologia , Hemocromatose/complicações , Neoplasias Hepáticas/etiologia , Idoso , Hemocromatose/genética , Humanos , Masculino
12.
Br J Surg ; 81(11): 1563-71, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7827876

RESUMO

When injected into the hepatic artery the contrast agent Lipiodol (iodized poppy seed oil) is selectively retained by hepatocellular carcinoma (HCC) for a prolonged period of time. Liver computed tomography (CT) performed after Lipiodol angiography is more sensitive than ordinary CT at imaging HCC. Arterial administration of cytotoxic drugs and radioisotopes conjugated to Lipiodol has been shown to be reasonably safe in patients with irresectable HCC. These therapies, often combined with embolization, provide effective palliation, better tumour response and improved survival compared with other available treatments. Their use as a preoperative adjunct to surgical resection of HCC is controversial.


Assuntos
Carcinoma Hepatocelular/terapia , Óleo Iodado/uso terapêutico , Neoplasias Hepáticas/terapia , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/metabolismo , Humanos , Óleo Iodado/metabolismo , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/metabolismo , Tomografia Computadorizada por Raios X
14.
Br J Radiol ; 67(800): 822-4, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8087492

RESUMO

Lipiodol, an iodinated derivative of poppyseed oil, is selectively retained in hepatocellular carcinoma and has been used as a vehicle to deliver localized doses of chemotherapeutic and radioactive agents to such tumours, thereby reducing the problems of external beam irradiation and the systemic toxicity of chemotherapy. We describe the first reported case where Lipiodol-targeted radiotherapy has been administered to a patient with secondary renal cell carcinoma in the liver. Localization was good and there were no complications. This case suggests that in future such patients may benefit from this therapy for unresectable lesions.


Assuntos
Carcinoma de Células Renais/radioterapia , Carcinoma de Células Renais/secundário , Radioisótopos do Iodo/uso terapêutico , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Portadores de Fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
15.
Invest Radiol ; 29(4): 434-42, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8034449

RESUMO

RATIONALE AND OBJECTIVES: The authors present phantom validation of a method for computing pulsatile flow waveforms in arterial vessels from high-frame-rate biplane x-ray angiograms. METHODS: The three-dimensional course of a blood vessel is constructed from biplane digital x-ray angiograms. A parametric image of contrast mass versus time and true three-dimensional path length is generated. Adjacent contrast mass-distance profiles are matched to compute instantaneous velocity, which is multiplied by cross-sectional area to yield volume flow. An electromagnetic flowmeter was used to validate flow estimates in a phantom consisting of 150-mm tubes 3, 4, and 6 mm in diameter, orientated 15 degrees, 30 degrees, and 35 degrees to the imaging plane, with flow rates and waveforms expected in vivo. RESULTS: Mean and peak flows were accurate to within 9% and 10%, respectively, for velocities of less than 1 meter/second at a frame rate of 25 frames per second. CONCLUSIONS: A practical method for computing highly pulsatile flow waveforms in vivo in tortuous vessels is presented.


Assuntos
Algoritmos , Angiografia Digital , Processamento de Imagem Assistida por Computador , Velocidade do Fluxo Sanguíneo/fisiologia , Vasos Sanguíneos , Humanos , Modelos Cardiovasculares , Modelos Estruturais , Fluxo Pulsátil/fisiologia
18.
HPB Surg ; 7(3): 185-99; discussion 200, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8155585

RESUMO

The therapeutic potential of 131I-Lipiodol was investigated in 8 patients with cholangiocarcinoma (CCA) and 15 patients with hepatocellular carcinoma (HCC). Patients received one or two doses of 131I-Lipiodol via hepatic arterial injection. The mean total administered activity was 668 (SD 325) MBq in CCA and 953 (SD 477) MBq in HCC. One patient with CCA retained 131I-Lipiodol. The cumulative radiation dose was 9.6 Gy to tumour, 6.4 Gy to liver and 1.5 Gy to lung. The patient remained asymptomatic with no evidence of tumour 30 months from the start of treatment, whereas the remaining 7 patients exhibited tumour progression. The mean survival in CCA was 11.6 (SD 14.5) months. All 15 patients with HCC retained 131I with tumour: liver ratios of up to 30:1. The mean cumulative radiation dose was 34.7 (SD 32.4) Gy to tumour, 3.3 (SD 1.5) Gy to liver and 4.4 (SD 2.3) Gy to lung. The mean dose per administered activity was 3.8 (SD 4.1) cGy/MBq. Partial response (reduction in tumour size > 50%) was observed in 6 patients (40%). The mean survival was 7.1 (SD 6.0) months. 131I-Lipiodol can deliver highly selective internal irradiation to foci of HCC with evidence of objective response and may be the treatment of choice for patients with cirrhosis and a small tumour.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/radioterapia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/radioterapia , Radioisótopos do Iodo/farmacocinética , Radioisótopos do Iodo/uso terapêutico , Óleo Iodado/farmacocinética , Óleo Iodado/uso terapêutico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/radioterapia , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Feminino , Seguimentos , Câmaras gama , Humanos , Radioisótopos do Iodo/efeitos adversos , Óleo Iodado/efeitos adversos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cintilografia , Indução de Remissão , Taxa de Sobrevida , Coloide de Enxofre Marcado com Tecnécio Tc 99m , Resultado do Tratamento
19.
HPB Surg ; 7(4): 291-6, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8204548

RESUMO

Of 61 consecutive patients undergoing laparoscopic cholecystectomy, 4 (6.25%) developed abdominal wall haematomas. This complication of laparoscopic cholecystectomy may occur more commonly than existing literature suggests, and manifests in the post-operative period (days 2 to 6) by visible bruising, excessive pain or an asymptomatic drop in haematocrit. It is readily confirmed by ultrasonography. While no specific treatment is necessary apart from replacement of significant blood loss, the patient requires reassurance that this apparently alarming complication will rapidly resolve.


Assuntos
Músculos Abdominais , Colecistectomia Laparoscópica/efeitos adversos , Hematoma/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculares/etiologia
20.
Hepatology ; 18(6): 1399-403, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8244264

RESUMO

In patients with obstructive jaundice due to biliary tract stricture a tissue diagnosis is essential because of the varied treatment options available. Radiological imaging of a biliary stricture may suggest that it is malignant, but only a tissue diagnosis can be conclusive. The difficulty of obtaining biopsy tissue has encouraged the use of cytology in this field. This study prospectively analyzed the diagnostic value of exfoliative bile and brush cytology methods. One hundred consecutive patients with biliary strictures diagnosed at endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography (60 men and 40 women; median age = 71 yr, range = 31 to 91 yr) underwent biliary cytology and were divided into two groups. Group 1 comprised the first 47 patients, who were studied by means of bile cytology alone; and group 2 comprised the subsequent 46 patients, who were studied by means of bile and brush cytology techniques. Seven patients were excluded from analysis because of inadequate follow-up information. A single experienced cytologist examined all samples to determine whether they were neoplastic. Eighty-one patients had malignant strictures and 12 had benign strictures. Combined bile and brush cytology (group 2) was more sensitive than bile cytology alone (group 1) (69% [27 of 39] vs. 33% [16 of 42], p < 0.01). In the patients studied by means of bile and brush cytology methods (group 2), cytologic study of brushings was more sensitive (69% vs. 26%, p < 0.01). No false-positive results were reported in either group (specificity = 100%).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doenças dos Ductos Biliares/patologia , Ductos Biliares/patologia , Bile/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças dos Ductos Biliares/diagnóstico por imagem , Doenças dos Ductos Biliares/etiologia , Neoplasias dos Ductos Biliares/complicações , Colangiografia/métodos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/etiologia , Constrição Patológica/patologia , Técnicas Citológicas , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
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