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1.
JAMA ; 330(19): 1862-1871, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37824132

RESUMO

Importance: Bleeding is the most common cause of preventable death after trauma. Objective: To determine the effectiveness of resuscitative endovascular balloon occlusion of the aorta (REBOA) when used in the emergency department along with standard care vs standard care alone on mortality in trauma patients with exsanguinating hemorrhage. Design, Setting, and Participants: Pragmatic, bayesian, randomized clinical trial conducted at 16 major trauma centers in the UK. Patients aged 16 years or older with exsanguinating hemorrhage were enrolled between October 2017 and March 2022 and followed up for 90 days. Intervention: Patients were randomly assigned (1:1 allocation) to a strategy that included REBOA and standard care (n = 46) or standard care alone (n = 44). Main Outcomes and Measures: The primary outcome was all-cause mortality at 90 days. Ten secondary outcomes included mortality at 6 months, while in the hospital, and within 24 hours, 6 hours, or 3 hours; the need for definitive hemorrhage control procedures; time to commencement of definitive hemorrhage control procedures; complications; length of stay; blood product use; and cause of death. Results: Of the 90 patients (median age, 41 years [IQR, 31-59 years]; 62 [69%] were male; and the median Injury Severity Score was 41 [IQR, 29-50]) randomized, 89 were included in the primary outcome analysis because 1 patient in the standard care alone group declined to provide consent for continued participation and data collection 4 days after enrollment. At 90 days, 25 of 46 patients (54%) had experienced all-cause mortality in the REBOA and standard care group vs 18 of 43 patients (42%) in the standard care alone group (odds ratio [OR], 1.58 [95% credible interval, 0.72-3.52]; posterior probability of an OR >1 [indicating increased odds of death with REBOA], 86.9%). Among the 10 secondary outcomes, the ORs for mortality and the posterior probabilities of an OR greater than 1 for 6-month, in-hospital, and 24-, 6-, or 3-hour mortality were all increased in the REBOA and standard care group, and the ORs were increased with earlier mortality end points. There were more deaths due to bleeding in the REBOA and standard care group (8 of 25 patients [32%]) than in standard care alone group (3 of 18 patients [17%]), and most occurred within 24 hours. Conclusions and Relevance: In trauma patients with exsanguinating hemorrhage, a strategy of REBOA and standard care in the emergency department does not reduce, and may increase, mortality compared with standard care alone. Trial Registration: isrctn.org Identifier: ISRCTN16184981.


Assuntos
Oclusão com Balão , Exsanguinação , Humanos , Masculino , Adulto , Feminino , Exsanguinação/complicações , Teorema de Bayes , Estudos Retrospectivos , Hemorragia/etiologia , Hemorragia/terapia , Aorta , Oclusão com Balão/efeitos adversos , Oclusão com Balão/métodos , Ressuscitação/métodos , Escala de Gravidade do Ferimento , Serviço Hospitalar de Emergência , Reino Unido
2.
J Clin Biochem Nutr ; 44(1): 85-94, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19177193

RESUMO

In dietary iron overload, excess hepatic iron promotes liver damage. The aim was to attenuate free radical-induced liver damage using vitamins. Four groups of 60 Wistar rats were studied: group 1 (control) was fed normal diet, group 2 (Fe) 2.5% pentacarbonyl iron (CI) followed by 0.5% Ferrocene, group 3 (Fe + V gp) CI, Ferrocene, plus vitamins A and E (42x and 10x RDA, respectively), group 4 (Fe - V gp) CI, Ferrocene diet, minus vitamins A and E. At 20 months, glutathione peroxidase (GPx), superoxide dismutase (SOD), Oxygen Radical Absorbance Capacity (ORAC), Ames mutagenicity test, AST, ALT and 4-hydroxynonenal (4-HNE) immunohistochemistry were measured. 8OHdG levels of the Fe + V and Fe - V groups were 346 +/- 117 and 455 +/- 151, ng/g w.wt, respectively. Fe + V and Fe - V differences were significant (p<0.005). A positive correlation between DNA damage and mutagenesis existed (p<0.005) within the iron-fed gps. AST levels for Fe + V and Fe - V groups were 134.6 +/- 48.6 IU and 202.2 +/- 50.5 IU, respectively. Similarly, ALT levels were 234.6 +/- 48.3 IU and 329.0 +/- 48.6 IU, respectively. However, Fe - V and Fe + V groups transaminases were statistically insignificant. 4-HNE was detected in Fe + V and Fe - V gp livers. Vitamins A and E could not prevent hepatic damage.

3.
Toxicology ; 219(1-3): 41-52, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16337327

RESUMO

BACKGROUND/AIMS: Excess hepatic iron may be both directly and indirectly carcinogenic. The aim of this study was to determine if generation of reactive oxygen species and the resulting oxidative damage induced by free hepatic iron is directly hepatocarcinogenic. METHODS: Sixty male Wistar albino rats were iron-loaded by ferrocene supplementation of their diet. Biochemical parameters of oxidative damage and lipid peroxidation, DNA unwinding and strand breaks, and the Ames Mutagenesis Test were measured at 4 monthly intervals and correlated with the degree of hepatic iron overload, the presence of iron-free preneoplastic foci in the liver, and the development of hepatocellular carcinoma in comparison with 60 control rats. RESULTS: Levels of lipid hydroperoxides, malonaldehyde, 8-isoprostane and 8-hydroxy-2'-deoxyguanosine increased, reaching peak concentrations at 20-24 months, and correlating with an increase in the rate of DNA unwinding, strand breaks, and positive Ames Tests. Iron-free neoplastic foci became evident at 16 months and thereafter increased in number. Preneoplastic foci were present in five of eight rats remaining at 32 months and HCC had developed in one of the five. CONCLUSIONS: Our findings are compatible with the hypothesis that the direct hepatocarcinogenic effect of free iron is mediated by the generation of oxygen reactive species and oxidative damage that are mutagenic and carcinogenic.


Assuntos
Sobrecarga de Ferro/complicações , Neoplasias Hepáticas Experimentais/induzido quimicamente , Animais , Dano ao DNA/efeitos dos fármacos , DNA Helicases/química , DNA Helicases/metabolismo , Eletroforese em Gel de Campo Pulsado , Fluorometria , Imuno-Histoquímica , Técnicas In Vitro , Ferro/sangue , Ferro/metabolismo , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Salmonella typhimurium/genética , Superóxidos/metabolismo , Transaminases/metabolismo , alfa-Fetoproteínas/metabolismo
4.
J Pathol ; 208(1): 82-90, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16278820

RESUMO

Although excess hepatic iron in hereditary haemochromatosis and dietary iron overload in the African causes hepatocellular carcinoma, it usually does so in the presence of cirrhosis. A direct hepatocarcinogenic effect of iron has not been proved. Moreover, an animal model of hepatocellular carcinoma induced by iron overload has not been available. The aim of this study was to develop such a model and to use it to ascertain whether excess hepatic iron is directly hepatocarcinogenic. Sixty Wistar albino rats were fed a chow diet and 60 the same diet supplemented initially with 2% carbonyl iron for 12 months, followed by 0.5% ferrocene for 20 months. Five rats from each group were sacrificed every 4 months for 24 months for histological and biochemical monitoring. By 16 months, hepatocytes in all the rats receiving the iron-supplemented diet showed grade 4 iron overload, comparable in degree with that seen in patients with advanced hereditary haemochromatosis and dietary iron overload. Altered hepatic foci and pre-neoplastic nodules were first seen at 16 months. These increased in size and number with time, were iron-free, stained positively with placental glutathione sulphydryl transferase, and showed the same histological features as the iron-free foci described in patients with hepatocellular carcinoma complicating hereditary haemochromatosis. At 32 months the eight surviving rats in the iron overloaded group were sacrificed. The livers of five of these rats contained pre-neoplastic nodules and one showed, in addition, an iron-free, well-differentiated hepatocellular carcinoma. The tumour stained positively for placental glutathione sulphydryl transferase. Neither cirrhosis nor portal fibrosis was present in this or any iron-loaded animal. We conclude that hepatocellular carcinoma may complicate dietary hepatic iron overload in Wistar albino rats in the absence of fibrosis or cirrhosis, confirming an aetiological association between dietary iron overload and the tumour and suggesting that iron may be directly hepatocarcinogenic.


Assuntos
Ferro/administração & dosagem , Neoplasias Hepáticas Experimentais/etiologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Suplementos Nutricionais , Modelos Animais de Doenças , Compostos Ferrosos/administração & dosagem , Compostos Ferrosos/metabolismo , Imuno-Histoquímica/métodos , Ferro/análise , Ferro/metabolismo , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/patologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Metalocenos , Ratos , Ratos Wistar
5.
J Surg Oncol ; 91(4): 258-63, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16121349

RESUMO

BACKGROUND AND OBJECTIVES: To ascertain the prevalence of deregulating mutations of beta-catenin gene, and to correlate this with the occurrence of 249(serine) p53 gene mutation and hepatitis B virus infection in southern African Blacks with hepatocellular carcinoma. METHODS: Paired cancer/non-cancerous liver tissues from 21 and cancer tissues alone from 20 Black Africans with hepatocellular carcinoma were studied. RT-PCR-SSCP and sequencing were used to detect mutations in exon 3 of the beta-catenin gene, and PCR, restriction endonuclease analysis, and sequencing to detect the p53 gene mutation. Immunostaining was used to identify beta-catenin protein expression in hepatocytes. RESULTS: No mutations in exon 3 of the beta-catenin gene were found in tumor or non-tumorous tissues. Immunohistochemical staining showed beta-catenin protein expression in membranes and cytoplasm of hepatocytes but not in the nuclei. The 249serine p53 gene mutation was detected in 27.2% of the hepatocellular carcinoma tissues but not in non-cancerous tissues. No correlation was found between beta-catenin mutation and over-expression and 249serine p53 gene mutations or hepatitis B virus surface antigenemia. CONCLUSIONS: Unlike hepatocellular carcinomas in China, Japan, and Europe, deregulating beta-catenin gene mutations do not appear to occur in southern African Blacks with this tumor and do not therefore interact with either the 249serine p53 gene mutation or hepatitis B virus infection in its pathogenesis.


Assuntos
População Negra/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Proteínas do Citoesqueleto/genética , Genes p53 , Hepatite B/complicações , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Transativadores/genética , África Austral , Carcinoma Hepatocelular/fisiopatologia , Análise Mutacional de DNA , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta Catenina
6.
Br J Haematol ; 116(3): 528-37, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11849208

RESUMO

2-chlorodeoxyadenosine (2-CdA) and arabinosylcytosine (araC) are nucleoside drugs that are used to treat various leukaemias, although 2-CdA has not been tested extensively in children with acute lymphoblastic leukaemia (ALL). Nucleoside cytotoxicity depends on the conversion of these agents to 5'-phosphate derivatives, following drug entry into cells via nucleoside transport (NT) processes. This study compared es nucleoside transporter content, determined using a flow cytometric assay with SAENTA [5'-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5'-thioadenosine] fluorescein, and cytotoxicities of 2-CdA and araC in fresh lymphoblasts from previously untreated paediatric ALL patients and the human T-lymphoblast cell line, CCRF-CEM. Lymphoblast samples from individual patients ranged widely in sensitivity to both 2-CdA (IC50, 6 nmol/l to > 5 micromol/l; mean = 418 nmol/l; n = 8) and araC (IC50, 59 nmol/l to > 5 micromol/l; mean = 1050 nmol/l; n = 7), although IC50 values for the two drugs were correlated (r = 0.78, P = 0.032, n = 7). Cellular es nucleoside transporter content varied more than 35-fold among samples from 10 patients. The correlation between es nucleoside transporter content and drug sensitivity was statistically significant for araC (r = -0.93, P = 0.023, n = 5), but not for 2-CdA (r = -0.57, P = 0.23, n = 6). Exposure of CCRF-CEM cells to araC resulted in a substantial araC concentration-dependent increase in the relative survival of es transporter-deficient cells, whereas the increase was slight following exposure to 2-CdA. We conclude that, in ALL lymphoblasts, es nucleoside transporter content is a determinant of araC sensitivity and that a deficiency in NT may impart resistance to araC.


Assuntos
Antineoplásicos/farmacologia , Cladribina/farmacologia , Citarabina/farmacologia , Linfócitos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Antimetabólitos Antineoplásicos/farmacologia , Proteínas de Transporte/análise , Sobrevivência Celular/efeitos dos fármacos , Criança , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Humanos , Imunofenotipagem , Linfócitos/metabolismo , Proteínas de Membrana/análise , Proteínas de Transporte de Nucleosídeos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Células Tumorais Cultivadas
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