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1.
HPB Surg ; 2013: 861681, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24062601

RESUMO

Introduction. In the UK, patients where liver resection is contemplated are discussed at hepatobiliary multidisciplinary team (MDT) meetings. The aim was to assess MDT performance by identification of patients where radiological and pathological diagnoses differed. Materials and Methods. A retrospective review of a prospectively maintained database of all cases undergoing liver resection from March 2006 to January 2012 was performed. The presumed diagnosis as a result of radiological investigation and MDT discussion is recorded at the time of surgery. Imaging was reviewed by specialist gastrointestinal radiologists, and resultswereagreedonby consensus. Results. Four hundred and thirty-eight patients were studied. There was a significant increase in the use of preoperative imaging modalities (P ≤ 0.01) but no change in the rate of discrepant diagnosis over time. Forty-two individuals were identified whose final histological diagnosis was different to that following MDT discussion (9.6%). These included 30% of patients diagnosed preoperatively with hepatocellular carcinoma and 25% with cholangiocarcinoma of a major duct. Discussion. MDT assessment of patients preoperatively is accurate in terms of diagnosis. The highest rate of discrepancies occurred in patients with focal lesions without chronic liver disease or primary cancer, where hepatocellular carcinoma was overdiagnosed and peripheral cholangiocarcinoma underdiagnosed, where particular care should be taken. Additional care should be taken in these groups and preoperative multimodality imaging considered.

2.
Clin Radiol ; 68(4): 323-35, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23391284

RESUMO

Pancreatic and biliary disease continues to have a significant impact on the workload of the National Health Service (NHS), for which there exists a multimodality approach to investigation and diagnosis. Endoscopic ultrasound (EUS) is fast becoming a fundamental tool in this cohort of patients, not only because of its ability to provide superior visualization of a difficult anatomical region, but also because of its valuable role as a problem-solving tool and ever-improving ability in an interventional capacity. We provide a comprehensive review of the benefits of EUS in everyday clinical practice.


Assuntos
Doenças Biliares/diagnóstico por imagem , Endossonografia/métodos , Pancreatopatias/diagnóstico por imagem , Sistema Biliar/diagnóstico por imagem , Humanos , Pâncreas/diagnóstico por imagem
3.
Clin Radiol ; 67(6): 535-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22208962

RESUMO

AIM: To evaluate the role of 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/ computed tomography (CT) in the current multidisciplinary management of anal cancer, both in initial staging and in follow-up post-treatment. MATERIALS AND METHODS: All patients referred to the region-wide multidisciplinary meeting for anal cancer during the study period received PET/CT imaging in addition to conventional imaging [CT and magnetic resonance imaging (MRI)]. Whether PET/CT altered the stage of the tumour from that suggested by conventional imaging was retrospectively assessed. The effect on management was evaluated. RESULTS: Fifty PET/CT examinations were performed on 44 patients with anal cancer. Thirty were part of initial staging, and 20 were post-chemo/radiotherapy or surgery. Two PET/CTs produced inadequate contemporaneous conventional imaging to allow comparison. Overall PET/CT increased the stage of the anal cancer in 17% of cases (8/48), decreased the stage in 19% (9/48), and did not alter the stage in 65% (31/48). The tumour stage was altered more frequently in initial staging than in follow up imaging. The PET/CT findings altered patient management in 29% (14/48) of cases. The majority (11) of these were cases in which PET/CT was used as part of initial staging. CONCLUSION: PET/CT alters the initial staging sufficiently frequently that it should be used routinely in anal cancer, where it is available. The role of PET/CT in the follow-up of anal cancer is not as clear. Routine follow-up with PET/CT may not be justified, but selected use is of definite benefit in problem solving or if salvage surgery is planned, after multidisciplinary discussion.


Assuntos
Neoplasias do Ânus/diagnóstico por imagem , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Neoplasias do Ânus/patologia , Neoplasias do Ânus/terapia , Fluordesoxiglucose F18 , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias/métodos , Compostos Radiofarmacêuticos , Estudos Retrospectivos
4.
Clin Radiol ; 66(11): 1086-93, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21840516

RESUMO

Ductal plate malformations, also known as fibrocystic liver diseases, are a group of congenital disorders resulting from abnormal embryogenesis of the biliary ductal system. The abnormalities include choledochal cyst, Caroli's disease and Caroli's syndrome, adult autosomal dominant polycystic liver disease, and biliary hamartoma. The hepatic lesions can be associated with renal anomalies such as autosomal recessive polycystic kidney disease (ARPKD), medullary sponge kidney, and nephronophthisis. A clear knowledge of the embryology and pathogenesis of the ductal plate is central to the understanding of the characteristic imaging appearances of these complex disorders. Accurate diagnosis of ductal plate malformations is important to direct appropriate clinical management and prevent misdiagnosis.


Assuntos
Doenças dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos/anormalidades , Hamartoma/diagnóstico , Adulto , Doenças dos Ductos Biliares/congênito , Doenças dos Ductos Biliares/diagnóstico por imagem , Doenças dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Doença de Caroli/diagnóstico , Diagnóstico Diferencial , Hamartoma/diagnóstico por imagem , Hamartoma/patologia , Humanos , Cirrose Hepática/congênito , Cirrose Hepática/diagnóstico , Pessoa de Meia-Idade , Rim Policístico Autossômico Recessivo/diagnóstico , Radiografia , Ultrassonografia
8.
J Med Chem ; 44(23): 3915-24, 2001 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-11689077

RESUMO

Several sulfide (+)-brefeldin A (BFA) analogues were prepared through the Michael addition of various thiols. Many of the sulfides were also oxidized to the corresponding sulfoxide with m-CPBA. The sulfides were designed to act as BFA prodrugs via the metabolic oxidation to the sulfoxide and subsequent syn elimination. Kinetic experiments were used to prove that the syn elimination of the sulfoxides prepared did in fact take place. Five selenide BFA prodrugs were also prepared that are envisioned to act in the same manner as the sulfides. As expected, when oxidation of the selenide to selenoxide was attempted, in situ syn elimination was observed. All of the compounds prepared were evaluated for antiproliferative activity against human cancer cell lines in the National Cancer Institute screen. The sulfoxides were much more potent than either the sulfides or selenides. Especially notable were sulfoxide 21, which possessed a cytotoxicity mean graph midpoint value (MGM) value lower than BFA itself, and sulfoxide 22, which possessed an MGM value slightly less potent than that of BFA. The sulfide analogues were shown to possess increased aqueous solubilty with respect to BFA.


Assuntos
Antibacterianos/síntese química , Antibióticos Antineoplásicos/síntese química , Brefeldina A/análogos & derivados , Brefeldina A/síntese química , Pró-Fármacos/síntese química , Sulfetos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Brefeldina A/química , Brefeldina A/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cinética , Macrolídeos , Espectroscopia de Ressonância Magnética , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade , Sulfetos/química , Sulfetos/farmacologia , Células Tumorais Cultivadas
9.
Eur J Emerg Med ; 8(2): 151-2, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11436913

RESUMO

Visualization of pre-cervical soft tissue swelling on a lateral radiograph is an important indicator of possible bony injury in the context of cervical spine trauma. We report a case where apparent swelling was in fact an artefact due to an inappropriately placed endotracheal tube. We recommend review of the position of endotracheal tubes when interpreting pre-cervical soft tissue swelling.


Assuntos
Artefatos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/lesões , Traumatismo Múltiplo/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Erros de Diagnóstico , Edema/diagnóstico por imagem , Humanos , Intubação Intratraqueal/efeitos adversos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Lesões dos Tecidos Moles/diagnóstico por imagem , Tomografia Computadorizada por Raios X
10.
AJR Am J Roentgenol ; 175(6): 1627-30, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11090391

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the efficacy and complications of percutaneous 18-gauge core biopsies of lesions of the bowel wall using CT and sonographic guidance. A retrospective study was made of 15 biopsy procedures performed on 12 patients with suspected neoplasia of the gastrointestinal tract. The biopsies were performed when there were no sites of metastatic disease more readily accessible to biopsy and the lesion was inaccessible to endoscopic techniques or when the endoscopic biopsy findings were negative. CONCLUSION: Three biopsy procedures provided inadequate samples and the biopsies were repeated, giving a total of 15 biopsy procedures. A tissue diagnosis was made in all 12 patients. All procedures were well tolerated, and no immediate or delayed complications occurred. Percutaneous core biopsy of bowel wall masses is a safe technique that allows a histologic diagnosis to be obtained in difficult cases when other methods cannot provide an adequate tissue sample.


Assuntos
Biópsia por Agulha/métodos , Intestinos/patologia , Idoso , Feminino , Neoplasias Gastrointestinais/patologia , Humanos , Masculino , Radiografia Intervencionista , Estudos Retrospectivos , Segurança , Manejo de Espécimes , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
11.
J Med Chem ; 43(20): 3688-98, 2000 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11020283

RESUMO

In an attempt to design and synthesize potential anticancer agents acting by inhibition of topoisomerase I (top1), a new series of indenoisoquinolines was prepared and tested for cytotoxicity in human cancer cell cultures and for activity against top1. The synthesis relied on the condensation of substituted Schiff bases with homophthalic anhydrides to produce cis-3-aryl-4-carboxyisoquinolones that were cyclized to indenoisoquinolines in the presence of thionyl chloride. Both top1 inhibitory activity and cytotoxicity maximized in a single compound, 6-[3-(2-hydroxyethyl)aminopropyl]-5,6-dihydro-2,3-dimethoxy-8, 9-methylenedioxy-5,11-dioxo-11H-indeno[1,2-c]isoquinoline hydrochloride (19a), which proved to be a very potent top1 inhibitor having a 110 nM mean graph midpoint (MGM) when tested for cytotoxicity in 55 human cancer cell cultures. A number of structurally related indenoisoquinolines were also obtained that had both potent cytotoxicity as well as top1 inhibitory activity. The key feature of the more potent compounds was the presence of an aminoalkyl side chain on the indenoisoquinoline nitrogen atom. The DNA cleavage patterns induced by top1 in the presence of the indenoisoquinolines were different from those seen with camptothecin. Some of the cleavage sites induced by the indenoisoquinolines were different from those seen with camptothecin, and conversely, camptothecin induced unique cleavage sites not apparent with the indenoisoquinolines. However, both camptothecin and the indenoisoquinolines also induced DNA cleavage sites that were the same in both series but varied in intensity. In addition, some of the DNA cleavages seen with the free base of 19a (compound 18c) in the presence of top1 were inhibited at higher drug concentrations, suggesting either a direct inhibition of the enzyme or an alternative mechanism involving DNA intercalation. Consistent with intercalation, compound 18c did unwind DNA.


Assuntos
Antineoplásicos/síntese química , Inibidores Enzimáticos/síntese química , Indenos/síntese química , Isoquinolinas/síntese química , Inibidores da Topoisomerase I , Antineoplásicos/química , Antineoplásicos/farmacologia , DNA Super-Helicoidal/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Indenos/química , Indenos/farmacologia , Isoquinolinas/química , Isoquinolinas/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
13.
J Arthroplasty ; 14(7): 800-2, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10537253

RESUMO

We studied the position of the popliteal artery in 32 patients with primary osteoarthritis of the knee. A total of 45 knees were studied using a noninvasive technique with color-flow duplex scanning. The distance between the popliteal artery and the posterior tibial cortex was measured in various positions of flexion. The distance separating them was found to be maximal between 60 degrees and 90 degrees. The study was repeated in a smaller series of 17 patients (20 knees) after knee replacement but with less conclusive results. We believe the safest position on which to operate in primary arthroplasty is with the knee in flexion, but the safety margins are not the same in revision surgery.


Assuntos
Articulação do Joelho/patologia , Osteoartrite do Joelho/cirurgia , Artéria Poplítea/patologia , Artroplastia do Joelho/métodos , Humanos , Artéria Poplítea/diagnóstico por imagem , Tíbia/patologia , Ultrassonografia
14.
Clin Radiol ; 53(9): 702-4, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9766726

RESUMO

Three patients who were investigated with dynamic contrast medium enhanced computed tomography (CT) of the thorax were noted to have pericardial effusions with reflux of contrast medium back along the azygos vein. The diagnosis of cardiac tamponade was not made clinically, but in each case was suggested from the CT findings. Confirmation of the diagnosis was made in all three cases, two patients with echocardiography and one at post mortem. One patient made a rapid recovery following the insertion of a pericardial drain, another made a temporary recovery after pericardiocentesis but the third died. Thirty CT scans performed with similar protocol were reviewed and none of these demonstrated reflux along the azygos vein. The presence of contrast medium refluxing into the azygos vein implies significant haemodynamic disturbance, and in the presence of a pericardial effusion suggests the diagnosis of cardiac tamponade.


Assuntos
Veia Ázigos/diagnóstico por imagem , Tamponamento Cardíaco/diagnóstico por imagem , Meios de Contraste , Tomografia Computadorizada por Raios X , Adulto , Idoso , Tamponamento Cardíaco/complicações , Evolução Fatal , Humanos , Masculino , Derrame Pericárdico/diagnóstico por imagem
16.
Urology ; 44(2): 271-2, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8048206

RESUMO

Indigo carmine is generally believed to be a safe, biologically inert substance. Adverse reactions to the intravenous administration of this dye have been seen only rarely. We report a life-threatening anaphylactoid reaction to indigo carmine that may have been due to either a drug allergy or to its intrinsic serotonergic properties.


Assuntos
Espasmo Brônquico/induzido quimicamente , Toxidermias/etiologia , Hipotensão/induzido quimicamente , Índigo Carmim/efeitos adversos , Urticária/induzido quimicamente , Idoso , Espasmo Brônquico/complicações , Toxidermias/complicações , Humanos , Hipotensão/complicações , Índigo Carmim/administração & dosagem , Injeções Intravenosas , Masculino , Índice de Gravidade de Doença , Urticária/complicações
17.
Cancer Res ; 47(4): 1036-9, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3467841

RESUMO

Rat liver cytosol and buttermilk xanthine oxidase both converted 7-deoxypyrromycinone, the 7-deoxyaglycone of marcellomycin, a new anthracycline antibiotic, to a nonfluorescent compound under anaerobic conditions and in the presence of an electron donor. Reduced nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate were equally effective electron donors for liver cytosol, and xanthine was the best cofactor for xanthine oxidase. However, xanthine was inactive with liver cytosol. Reactions with xanthine oxidase obeyed Menten-Michaelis kinetics and were inhibited by allopurinol. No xanthine oxidase activity was detected in liver cytosol. Xanthine oxidase also induced a loss of fluorescence when incubated with 7-deoxydaunorubicin aglycone. The nonfluorescent metabolite of 7-deoxypyrromycinone was tentatively identified as the dihydroquinonic derivative of the parent deoxyaglycone on the basis of its spectrophotometric, fluorescent, thin layer chromatographic, and mass spectral characteristics. Our data demonstrate that more than one enzymatic activity, xanthine oxidase, and an unidentified rat liver cytosolic enzyme convert the 7-deoxyaglycones of anthracycline antibiotics to nonfluorescent metabolites.


Assuntos
Antraciclinas , Antibacterianos/metabolismo , Xantina Oxidase/metabolismo , Anaerobiose , Animais , Antibióticos Antineoplásicos , Daunorrubicina/metabolismo , Doxorrubicina/metabolismo , Cinética , Fígado/metabolismo , Masculino , Mitoxantrona/metabolismo , NAD/metabolismo , NADP/metabolismo , Naftacenos/metabolismo , Ratos , Ratos Endogâmicos
18.
Cancer Res ; 46(6): 2714-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3084076

RESUMO

The in vitro metabolism of marcellomycin by rat tissue fractions showed conversion of marcellomycin to 7-deoxypyrromycinone, bisanhydropyrromycinone, and an as yet unidentified compound by rat liver homogenate, microsomes, cytosol, and mitochondria, and purified hepatic reduced nicotinamide adenine dinucleotide phosphate-cytochrome P-450 reductase, under anaerobic conditions and in the presence of reduced nicotinamide adenine dinucleotide phosphate. All these fractions except the purified reductase subsequently induced a progressive loss of fluorescence. Mitochondria, however, were much less active than microsomes, cytosol, and homogenate in inducing this latter phenomenon. Marcellomycin was converted to 7-deoxyaglycones only partially by nuclei. No loss of fluorescence was observed with this subcellular fraction. No loss of fluorescence was observed when doxorubicin or daunorubicin were incubated under similar conditions. The appearance of a compound with distinct spectrophotometric properties was demonstrated by absorbance spectrometry. The formation of a compound with different fluorescent characteristics was excluded, as was the binding of the aglycones to subcellular components. The activity inducing the loss of fluorescence was studied in greater detail with cytosol. It predominated in the liver and required both an electron donor and anaerobic conditions. The optimal pH for the reaction was between 7.5 and 8.0. Our results suggest the existence of an enzymatic pathway capable of converting the fluorescent nucleus of marcellomycin to a nonfluorescent metabolite.


Assuntos
Antraciclinas , Antibióticos Antineoplásicos/metabolismo , Animais , Fluorescência , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Microssomos Hepáticos/metabolismo , NADPH-Ferri-Hemoproteína Redutase/análise , Naftacenos/metabolismo , Ratos , Ratos Endogâmicos , Especificidade por Substrato
19.
Cancer Treat Rep ; 69(7-8): 851-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4016794

RESUMO

We studied the effect of deoxyguanosine (dGuo) on cellular cytarabine (ara-C) nucleotide accumulation of the human leukemia cell line K562 and of bone marrow blast cells derived from patients with acute nonlymphocytic leukemia. Exposure of cells in culture to dGuo increased ara-C nucleotide accumulation measured in cell lysate, with an average increase of 386% (range, 242%-537%) of control in the presence of 500 microM dGuo. Maximal elevation occurred after 8 hours of exposure and remained constant through 48 hours. dGuo also enhanced deoxycytidine nucleotide accumulation, but dGuo enhancement favored accumulation of ara-C nucleotides over dCyd nucleotides. In cell cycle kinetic studies using flow cytometry, dGuo slowed accumulation of cells with apparent S-phase DNA content in a concentration-dependent fashion. However, neither the rate nor the magnitude of this effect correlated with the increase in ara-C nucleotide accumulation. Since the increase in ara-C nucleotide accumulation caused by dGuo could be prevented by 5 micrograms/ml of cycloheximide, this process appears to require new protein synthesis. Although these data suggest that the elevation of ara-C nucleotide accumulation caused by dGuo may represent induction of enzyme synthesis, other possibilities are discussed. Exposure of bone marrow blast cells obtained from patients with acute nonlymphocytic leukemia to dGuo for 16 hours in liquid culture also increased ara-C nucleotide accumulation. In six of seven studies, exposure to dGuo in concentrations from 50 to 500 microM increased ara-C nucleotide accumulation from 160% to 3400%. These data suggest that dGuo may alter ara-C metabolism in a clinically useful fashion.


Assuntos
Arabinofuranosilcitosina Trifosfato/biossíntese , Arabinonucleotídeos/biossíntese , Citarabina/metabolismo , Desoxiguanosina/farmacologia , Leucemia/metabolismo , Medula Óssea/metabolismo , Linhagem Celular , Cicloeximida/farmacologia , DNA de Neoplasias/metabolismo , Desoxicitidina Quinase/metabolismo , Citometria de Fluxo , Humanos , Interfase/efeitos dos fármacos , Fosforilação , Timidina/farmacologia
20.
Biophys Chem ; 22(1-2): 115-23, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2992620

RESUMO

The one-electron electrochemical reduction of diaziquone (AZQ) and 12 analogs is analyzed using ESR spectroscopy and cyclic voltammetry. The hyperfine coupling constants arising from the interaction of the unpaired electron with the aziridine nitrogen nuclei fall within 1.20 and 2.26 G. Smaller couplings are observed arising from the protons and nitrogens in the carboethoxyamino groups. The in vitro activity of AZQ and its analogs is examined. Methyl groups in the aziridine rings increase the activity of some analogs. In the absence of aziridines, a chloroquinone compound with only carboethoxyamino groups was surprisingly active. This compound has a more positive cathodic peak than diaziquone.


Assuntos
Aziridinas , Azirinas , Benzoquinonas , Animais , Aziridinas/farmacologia , Azirinas/farmacologia , Divisão Celular/efeitos dos fármacos , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Leucemia L1210/tratamento farmacológico , Camundongos , Relação Estrutura-Atividade
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