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1.
Free Radic Res ; 22(2): 99-107, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7704188

RESUMEN

Electron paramagnetic resonance spectroscopy (EPR) was used to study free radicals and transition metal complexes in liver tissue taken from patients with liver disease. Samples were frozen to 77K directly following biopsy to prevent deterioration. Our major aim was to compare signals from patients suffering from alcohol abuse with those from patients having liver damage not induced by alcohol. Samples were obtained from 19 chronic alcohol abusers and 7 non-alcoholic liver disease patients. Of the 19 alcoholic patients, 18 had an increased fat content, 6 had Mallory's hyaline, 12 had an acute inflammatory response, 9 had increased stainable iron and 4 had evidence of fibrosis. A signal derived from free radicals with a spectroscopic splitting factor of g = 2.0045 was found in all samples. This signal in the alcoholic patients had a mean amplitude of 2.96 cm (+/- 1.42 SD), and in patients with non-alcoholic liver disease 2.12 cm (+/- 0.82) (p = 0.10 NS), measured under identical instrument settings. The molar proportion of diene conjugated linoleic acid (DCLA), a free radical marker, in the sera of alcoholic patients was 2.68% (+/- 1.93), but did not correlate with the free radical signals obtained by EPR spectroscopy. Also, there was no correlation between the free radical derived EPR signal and fat content, Mallory's hyaline, inflammatory infiltrate, iron or fibrosis in the liver biopsy specimens. Similarly the concentrations of aspartate transaminase, albumin, and gamma-glutamyl transferase in serum samples showed no correlations with free radical concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón , Hepatopatías Alcohólicas/metabolismo , Hígado/química , Adulto , Anciano , Aspartato Aminotransferasas/sangre , Biopsia con Aguja , Femenino , Radicales Libres , Humanos , Hierro/análisis , Lípidos/análisis , Hígado/patología , Cirrosis Hepática/patología , Hepatopatías Alcohólicas/patología , Masculino , Manganeso/análisis , Persona de Mediana Edad , gamma-Glutamiltransferasa/sangre
2.
Hum Exp Toxicol ; 11(6): 553-4, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1361149

RESUMEN

A man presented with frank haematuria and a grossly prolonged prothrombin time. He was later found to have taken an overdose of difenacoum--a 'superwarfarin' rodenticide. The diagnosis was confirmed by a serum concentration of difenacoum of 0.6 micrograms ml-1. Overdosage with superwarfarins is discussed and the need for prolonged treatment with vitamin K1 highlighted.


Asunto(s)
4-Hidroxicumarinas/envenenamiento , Hematuria/inducido químicamente , Rodenticidas/envenenamiento , 4-Hidroxicumarinas/sangre , Adulto , Sobredosis de Droga , Hematuria/tratamiento farmacológico , Hematuria/fisiopatología , Humanos , Masculino , Tiempo de Protrombina , Rodenticidas/sangre , Vitamina K/uso terapéutico
3.
Osteoporos Int ; 16(1): 56-63, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15221205

RESUMEN

Calcium malabsorption, hypocalcemia and skeletal demineralization are well-recognized features of untreated celiac disease. This study investigates calcium absorption and bone mineral density (BMD) after a prolonged, over 4 years, treatment with a gluten-free diet. Twenty-four adult females with treated celiac disease and twenty age- and sex-matched control subjects were studied. Mean body mass index (MBI), energy intake, serum calcium, and serum 25(OH)D concentrations in treated celiacs did not differ from controls. However, while both dietary calcium and protein intake were significantly higher in celiacs (P<0.012), fractional calcium absorption was lower (mean percentage+/-SD; treated 39.8+/-12 versus controls 52.3+/-10, P<0.001). Thus, after adjusting for calcium intake, the estimated amount of calcium absorbed daily was similar in both groups. Whole body, spine and trochanter BMD were significantly lower in treated celiac patients compared with controls (P<0.05). There were significant inverse correlations between: serum parathyroid hormone (PTH) and femoral neck or total body BMD (P<0.01), PTH and duration of gluten-free diet (P=0.05), and fractional calcium absorption and alkaline phosphatase (P=0.022). Increased calcium intake could potentially compensate for the reduced fractional calcium absorption in treated adult celiac patients, but may not normalize the BMD. In addition, the inverse correlation between PTH and time following treatment is suggestive of a continuing long-term benefit of gluten withdrawal on bone metabolism in celiac patients.


Asunto(s)
Densidad Ósea/fisiología , Calcio/farmacocinética , Enfermedad Celíaca/dietoterapia , Dieta con Restricción de Proteínas/métodos , Vitamina D/análogos & derivados , Absorción , Adulto , Anciano , Fosfatasa Alcalina/sangre , Calcio/sangre , Calcio de la Dieta/administración & dosificación , Estudios de Casos y Controles , Enfermedad Celíaca/metabolismo , Enfermedad Celíaca/fisiopatología , Femenino , Glútenes , Humanos , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Vitamina D/sangre
4.
J Hepatol ; 19(1): 105-9, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8301030

RESUMEN

Alcoholics admitted for detoxification were entered into a double blind placebo controlled trial of oral supplementation with an antioxidant cocktail (vitamin E, beta carotene, vitamin C and selenium) in order to determine the effect of this supplementation on the rate of resolution of a serum marker of free radical activity and abnormal serum biochemistry. The molar proportion of linoleic acid that was diene conjugated (a marker of free radical activity), was increased in the alcoholics 2.9% +/- 1.2 (mean +/- S.D.) compared to normal controls 1.3% +/- 0.6 (P < 0.0001) but fell at a similar rate during the first week of hospitalisation in supplemented and placebo-treated patients with a mean fall of 53.7% (+/- 16.4 S.D.) in the placebo group and 56.0% (+/- 23.7) (P = 0.32, NS) in the antioxidant supplemented group. Similarly, there was no difference in the rate of fall between serum aspartate transaminase (AST) concentration in the two groups: the placebo group falling by a mean of 68.9% (+/- 35.2) and the antioxidant supplemented group falling by 70.1% (+/- 10.0) (P = 0.41, NS) over the first 7 days of hospitalization. Alcoholics had low serum concentrations of vitamin E compared with controls (15.6 mg/l +/- 6.2 S.D.) which rose more in the supplemented group over the period of a week (7.7 mg/l +/- 4.4 to 21.6 mg/l +/- 5.1) (a mean rise of 180.5%) compared with the placebo group (8.6 mg/l +/- 6.8 to 9.6 mg/l +/- 5.7)--a mean rise of 11.6% (P = 0.006).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Antioxidantes/administración & dosificación , Etanol/efectos adversos , Hepatopatías Alcohólicas/sangre , Síndrome de Abstinencia a Sustancias/sangre , Adulto , Anciano , Antioxidantes/metabolismo , Ácido Ascórbico/administración & dosificación , Biomarcadores/sangre , Carotenoides/administración & dosificación , Método Doble Ciego , Quimioterapia Combinada , Femenino , Radicales Libres , Pruebas Hematológicas , Humanos , Hepatopatías Alcohólicas/enzimología , Hepatopatías Alcohólicas/etiología , Masculino , Persona de Mediana Edad , Selenio/administración & dosificación , Síndrome de Abstinencia a Sustancias/complicaciones , Vitamina E/administración & dosificación , beta Caroteno
5.
Postgrad Med J ; 68(800): 465-6, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1437931

RESUMEN

We report the case of a 70 year old man who presented with physical and biochemical features suggestive of Addison's disease, but had a normal short tetracosactrin (Synacthen) test. Six months later he re-presented with similar clinical features but with an abnormal response to tetracosactrin confirming the diagnosis of Addison's disease. We recommend that if adrenal insufficiency is strongly suggested further investigation should be performed to exclude this diagnosis.


Asunto(s)
Enfermedad de Addison/diagnóstico , Cosintropina , Anciano , Reacciones Falso Negativas , Humanos , Masculino
6.
Gut ; 37(2): 220-4, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7557572

RESUMEN

Patients with coeliac disease may present with calcium malabsorption but it is unclear whether this results in longterm impairment of bone mineralisation. Dual energy x ray absorptiometry (DXA) was used to study bone mineral density in 34 asymptomatic coeliac disease patients, treated with a gluten free diet for at least two years, and also in 10 newly diagnosed or untreated patients. As expected, untreated patients had low bone mineral density in all regions. In the 29 treated female coeliac disease patients, overall mean values for age adjusted bone mineral density expressed as Z scores were normal although there were many patients with low values, particularly of the lumbar spine and total body. Scores in the postmenopausal patients were significantly worse than in the premenopausal patients and low mean Z scores were found in the five treated male patients. The subjects who had reduced bone mineral density could not be predicted clinically but, despite being asymptomatic, were more likely to have subtotal or partial villous atrophy on small intestinal biopsy (p < 0.0275). In conclusion, although many treated coeliac disease patients have normal bone mineral density, suboptimally treated and newly diagnosed or untreated patients have osteopenia. To reduce the risk of osteoporotic fractures, it is recommended that bone mineral density be measured in all treated coeliac disease patients and those with osteopenia have a repeat intestinal biopsy to assess disease activity.


Asunto(s)
Absorciometría de Fotón , Densidad Ósea , Enfermedad Celíaca/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades Óseas Metabólicas/etiología , Enfermedad Celíaca/complicaciones , Enfermedad Celíaca/dietoterapia , Enfermedad Celíaca/patología , Femenino , Humanos , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Posmenopausia
7.
Digestion ; 53(3-4): 142-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1291402

RESUMEN

The use of an ammonia electrode to quantify ammonia liberated by urease from Helicobacter pylori was assessed in an in vitro study. It was found to be highly sensitive (down to 0.7 ppm NH3) and highly reproducible (coefficient of variation 6.0%). Inhibition of urease by bismuth subsalicylate was evaluated as urease testing is often used to assess clearance of H. pylori in patients treated with bismuth. Concentrations of bismuth subsalicylate up to 5 mg/ml had no inhibitory effect but bismuth subsalicylate at 50 mg/ml resulted in 21% inhibition of the urease activity of an ultrasonicated H. pylori suspension. As a preliminary study, the ammonia electrode was assessed in the endoscopy room in comparison with conventional techniques for H. pylori diagnosis. Antral biopsies from 39 patients attending for routine diagnostic endoscopy were subjected to culture, histology, detection of urease activity with a commercially available slide test (CLO) and with the ammonia electrode to detect ammonia liberated from samples placed in urea solution. 21 patients were positive after 1 h with the ammonia electrode, compared to only 17 with the commercially available slide test. 20 were positive on histology and 19 by culture. All samples positive with the ammonia electrode were either positive by culture or by histology. The ammonia electrode offers a quick, sensitive, quantitative and cheap method for the detection and quantification of H. pylori.


Asunto(s)
Bismuto/farmacología , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/enzimología , Compuestos Organometálicos/farmacología , Salicilatos/farmacología , Ureasa/análisis , Amoníaco , Electrodos , Femenino , Gastroscopía , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/aislamiento & purificación , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Ureasa/antagonistas & inhibidores
8.
Clin Sci (Lond) ; 84(3): 339-48, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8384957

RESUMEN

1. Electron paramagnetic resonance spectroscopy was used to study free-radical signals in freeze-clamped frozen liver tissue from rats after a 1 year period of dietary supplementation with alcohol, iron, or alcohol and iron. In alcohol-fed, iron-fed and alcohol- and iron-fed animals, mild histological damage was seen on light microscopy and evidence of mitochondrial and nuclear injury was identified by electron microscopy. 2. Subcellular fractionation studies showed an increase in the activity of the peroxisomal marker catalase (P < 0.01) in alcohol-fed rats compared with controls, but a fall of 82% (P < 0.001) in alcohol- and iron-fed animals. The activity of the mitochondrial marker succinate dehydrogenase rose by 7% (not significant) in alcohol-fed animals and by 17% (not significant) in iron-fed animals, but fell by 94% (P < 0.001) in alcohol- and iron-fed animals, suggesting serious impairment of mitochondrial function. 3. Iron overload was substantial in the iron-fed animals and there was an excellent correlation between liver iron concentration and iron-derived signals by electron paramagnetic resonance spectroscopy (P < 0.001). A clear free-radical signal of g = 2.003-2.005 was detected in all liver samples, but there was no significant difference in the magnitude of this signal in any study group. 4. The absence of any increase in the stable free-radical signal, even in the presence of considerable hepatic damage, does not support the hypothesis that free radicals mediate alcoholic liver disease in this animal model, although the results cannot be taken as proof against this hypothesis.


Asunto(s)
Hepatopatías/metabolismo , Hígado/química , Animales , Catalasa/análisis , Enfermedad Hepática Inducida por Sustancias y Drogas , Modelos Animales de Enfermedad , Espectroscopía de Resonancia por Spin del Electrón , Etanol/administración & dosificación , Femenino , Radicales Libres/análisis , Hierro/administración & dosificación , Hígado/enzimología , Hepatopatías/enzimología , Ratas , Ratas Wistar , Succinato Deshidrogenasa/análisis
9.
Gut ; 37(1): 144-7, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7672666

RESUMEN

A 15 year old boy with sickle cell disease developed intrahepatic cholestasis. A course of exchange transfusion successfully corrected the extreme hyperbilirubinaemia over one year. Upon stopping the exchange transfusion programme the hyperbilirubinaemia relapsed but transfusion was effective when reinstituted.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Colestasis Intrahepática/terapia , Recambio Total de Sangre , Adolescente , Enfermedad Crónica , Humanos , Hiperbilirrubinemia/terapia , Masculino , Recurrencia
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