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1.
Eur J Nutr ; 59(8): 3581-3590, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32078064

RESUMEN

PURPOSE: Endothelial dysfunction and inflammation are conditions which fuel atherosclerosis and ischaemic heart disease. We have previously reported reduced cardiovascular (CV) mortality following supplementation with selenium and coenzyme Q10 to 443 elderly individuals with low selenium status (mean 67 µg/L) for 4 years. Here, we wanted to evaluate a possible association between the supplementation and the plasma concentrations of the von Willebrand factor (vWf), and the plasminogen activator inhibitor-1 (PAI-1), as they, besides other functions, are also strongly associated with endothelial function. METHODS: In this sub-study, 308 individuals (active substance: 157, placebo: 151) were included. Blood samples were drawn after 6 and 36 months and vWf and PAI-1 were determined in plasma by ELISA. Changes in concentrations of the biomarkers were evaluated by the use of T tests, repeated measures of variance, and ANCOVA analyses. RESULTS: The active treatment group presented a lower level of vWf after 36 months compared with the placebo group (1.08 U/mL vs. 5.10 U/mL; p = 0.0007). The results were validated through the repeated measures of variance evaluation. The PAI-1 levels showed an equally significant decrease in the active group (26.2 ng/mL vs. 49.2 ng/mL; p = 0.0002) and were also validated through repeated measures of variance evaluation. CONCLUSION: In this sub-study on elderly receiving selenium and coenzyme Q10, or placebo we found significantly lower levels of vWf and PAI-1 in the active treatment group as compared to the placebo group. We interpret this as a better endothelial function because of the intervention, which accords with a previous finding of reduced CV mortality.


Asunto(s)
Enfermedades Cardiovasculares , Selenio , Anciano , Suplementos Dietéticos , Humanos , Inhibidor 1 de Activador Plasminogénico , Estudios Prospectivos , Activador de Tejido Plasminógeno , Ubiquinona/análogos & derivados , Factor de von Willebrand
2.
Eur J Clin Nutr ; 70(1): 91-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26105108

RESUMEN

BACKGROUND/OBJECTIVES: The daily dietary intake of selenium (Se), an essential trace element, is still low in Sweden in spite of decades of nutritional information campaigns and the effect of this on the public health is presently not well known. The objective of this study was to determine the serum Se levels in an elderly Swedish population and to analyze whether a low Se status had any influence on mortality. SUBJECTS/METHODS: Six-hundred sixty-eight (n=668) elderly participants were invited from a municipality and evaluated in an observational study. Individuals were followed for 6.8 years and Se levels were re-evaluated in 98 individuals after 48 months. Clinical examination of all individuals included functional classification, echocardiography, electrocardiogram and serum Se measurement. All mortality was registered and endpoints of mortality were assessed by Kaplan-Meier plots, and Cox proportional hazard ratios adjusted for potential confounding factors were calculated. RESULTS: The mean serum Se level of the study population (n=668) was 67.1 µg/l, corresponding to relatively low Se intake. After adjustment for male gender, smoking, ischemic heart disease, diabetes, chronic obstructive pulmonary disease and impaired heart function, persons with serum Se in the lowest quartile had 43% (95% confidence interval (CI): 1.02-2.00) and 56% (95% CI: 1.03-2.36) increased risk for all-cause and cardiovascular mortality, respectively. The result was not driven by inflammatory effects on Se concentration in serum. CONCLUSION: The mean serum Se concentration in an elderly Swedish population was 67.1 µg/l, which is below the physiological saturation level for several selenoprotein enzymes. This result may suggest the value of modest Se supplementation in order to improve the health of the Swedish population.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Enfermedades Carenciales/complicaciones , Estado Nutricional , Selenio/sangre , Oligoelementos/sangre , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/sangre , Causas de Muerte , Enfermedades Carenciales/sangre , Femenino , Humanos , Masculino , Modelos de Riesgos Proporcionales , Riesgo , Suecia/epidemiología
3.
Scand J Clin Lab Invest ; 67(3): 337-42, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17454848

RESUMEN

OBJECTIVE: To investigate the short-term effects of the tumour necrosis factor alpha (TNFalpha) antagonist infliximab on the acute phase reaction and activities of daily life (ADL) in patients with rheumatoid arthritis (RA). METHODS: Fourteen patients with active RA were treated with an intravenous infusion of 200 mg infliximab. The values of the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, granulocyte count, lymphocyte count, platelet count and a patient questionnaire score on ADL, the Health Assessment Questionnaire (HAQ), were obtained at baseline and on days 4 and 14. The significance levels and effect sizes (ESs) of the changes from baseline were calculated. RESULTS: Changes by day 4: The ESs and significance levels were: CRP 1.7, p<0.005; lymphocyte count 1.4, p<0.005; fibrinogen 0.9, p<0.005; ESR 0.7, p<0.005; and HAQ 0.6, p<0.01. Changes by day 14: CRP 1.6, p<0.005; ESR 1.5, p<0.005; fibrinogen 1.3, p<0.005; lymphocyte count 1.0, p<0.005; granulocyte count 0.7, p<0.05; and HAQ 0.6, p<0.05. CONCLUSION: CRP, fibrinogen and ESR showed the largest ESs and were thus the most sensitive variables showing the early effect of infliximab in this study. The score on ADL (HAQ) showed less ES, but still significant short-term improvements.


Asunto(s)
Actividades Cotidianas , Reacción de Fase Aguda/tratamiento farmacológico , Anticuerpos Monoclonales/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/fisiopatología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Anciano , Artritis Reumatoide/patología , Biomarcadores/metabolismo , Sedimentación Sanguínea/efectos de los fármacos , Proteína C-Reactiva/efectos de los fármacos , Proteína C-Reactiva/metabolismo , Femenino , Fibrinógeno/efectos de los fármacos , Fibrinógeno/metabolismo , Humanos , Infliximab , Masculino , Metotrexato/uso terapéutico , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/metabolismo
4.
Tidsskr Nor Laegeforen ; 121(8): 921-3, 2001 Mar 20.
Artículo en Noruego | MEDLINE | ID: mdl-11332379

RESUMEN

BACKGROUND: Treatment with thiazide diuretics is among the most frequent causes of severe hyponatremia. Previous reports indicate that elderly women develop more severe manifestations than men. The risk of developing hyponatremia increases when thiazide diuretics are given simultaneously with NSAIDs. MATERIAL AND METHODS: Three typical case-stories are presented, all cases being admitted to hospital with a tentative diagnosis of cerebrovascular stroke. RESULTS: It is shown that hyponatremia can give rise to a broad spectrum of symptoms, ranging from unspecific dizziness and headache to alarming neurological symptoms involving lethargy and severe confusion. As far as therapy is concerned, it is important to eliminate the cause of hyponatremia, and to carry out a controlled correction with isotonic or hypertonic saline. Too rapid correction can precipitate a serious complication called osmotic demyelination syndrome. INTERPRETATION: Differential diagnoses of hyponatremic conditions are discussed. Prescription of drugs that involve risk of hyponatremia should be preceded by a precise evaluation of the condition and the indication for such treatment.


Asunto(s)
Benzotiadiazinas , Hiponatremia/inducido químicamente , Inhibidores de los Simportadores del Cloruro de Sodio/efectos adversos , Anciano , Diagnóstico Diferencial , Diuréticos , Femenino , Humanos , Hiponatremia/diagnóstico
5.
J Trace Elem Med Biol ; 15(2-3): 167-74, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11787984

RESUMEN

In the present study 67 non-anaemic women were randomly allocated to either 100 mg or 15 mg iron daily at about the 10. week of pregnancy. At about week 18, 30 and 36 of pregnancy, as well as 6 weeks after delivery, hemoglobin and the serum concentrations of ferritin, vitamin B12, folates, Zn, Cu and Se were monitored. Dietary allowances of other minerals and vitamins are also increased in pregnancy, and the 15 mg iron tablet was enriched with Zn (10 mg), Cu (2 mg), Se (50 microg), vitamin B12 (3 microg), and folate (0.1 mg). Neither ferritin, nor Cu, Zn or Se concentrations differed statistically significantly between the treatment groups during pregnancy. Ferritin and Zn appeared to decrease approximately parallel to the hemodilution, whereas Cu concentrations increased from a non-pregnant reference mean of 18 micromol Cu/L to a maximum mean of nearly 33 micromol Cu/L during pregnancy. Se decreased concomitantly to about 1.0 micromol Se/L. Serum folate (around 15 micromol/L) was essentially unaffected by pregnancy in the group given multivitamin/mineral supplementation, whereas the mean concentration fell below 10 micromol/L in the group supplemented with 100 mg iron daily. Our results indicate that supplementation of 15 mg Fe daily during pregnancy results in a small reduction of hemoglobin. It is suggested that additional supplementation with folate might be of importance to maintain the serum folate concentration during pregnancy.


Asunto(s)
Suplementos Dietéticos , Hierro/farmacología , Adulto , Cobre/sangre , Femenino , Ácido Fólico/farmacología , Hemoglobinas/biosíntesis , Humanos , Noruega , Periodo Posparto , Embarazo , Selenio/sangre , Factores de Tiempo , Zinc/sangre
6.
Acta Medica (Hradec Kralove) ; 43(4): 129-32, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11294130

RESUMEN

A weight-reducing potential has been ascribed to high dietary fibre intake. To investigate the practical reliability of this hypothesis, fifty-three moderately overweight females (BMI > 27.5 kg/m2) on reduced energy intake (1200 kcal/day) were treated for 24 weeks with a fibre supplement on a randomly, double-blind, placebo-controlled basis. The fibre was administered as an initial dose of 6 g and a maintenance dose of 4 g. Body weight and blood pressure were recorded weekly during the first 3 months and thereafter every second week. Blood samples were drawn at start and at end of the study. Initial body weights were 75.6 +/- 1.6 kg in the fibre group versus 75.5 +/- 1.6 kg in the placebo group. After treatment, mean weight loss in the fibre group was 8.0 kg versus 5.8 kg in the placebo group (p < 0.05). Systolic and diastolic blood pressures were significantly reduced in both groups without differences between the groups. Serum concentrations of cholesterol, triglycerides and uric acid were significantly reduced in the group with reduced energy intake, whereas no additional effect was observed when fibre was supplemented. Serum concentrations of potassium and sodium did not change significantly. The results suggest that a dietary fibre supplement in combination with a hypocaloric diet is of value as an adjunct in the management of overweight.


Asunto(s)
Dieta Reductora , Fibras de la Dieta/administración & dosificación , Ingestión de Energía , Lípidos/sangre , Obesidad/tratamiento farmacológico , Pérdida de Peso , Adolescente , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Obesidad/sangre
7.
Biol Trace Elem Res ; 78(1-3): 35-42, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11314986

RESUMEN

Oxidative stress affecting the thyroxin biosynthesis might explain the proneness of patients with Down's syndrome (DS) (trisomia 21) to develop hypothyroidism. Thyroideal cells are exposed to endogenous H2O2 that acts as a cofactor for the iodination of thyroxin precursors. The gland has high levels of selenium-containing proteins, including peroxide-detoxicating enzyme proteins. The object of the present study was to explore the hypothesis of a role of an imbalance between toxic oxygen production and protective metalloenzymes during the development of thyroid hypofunction in DS patients. We analyzed serum levels of thyroid hormones and trace metals in 38 institutionalized adults with DS, using mentally retarded subjects matched for age, sex, and behavioral function as controls. The DS patients had significantly lower mean values of free thyroxin (fT4) and increased TSH (thyroid stimulating hormone), as compared to the controls. They had lower serum selenium than the controls. A positive correlation was observed between serum concentrations of fT4 and selenium in the DS patients (r = 0.393, p < 0.05). No significant differences were found between the fT4 or the TSH concentrations in the patients with and without circulating antithyroid autoantibodies. Our results support the suggestion that thyroid hypofunction in patients with Down's syndrome in some way is linked to the low serum levels of selenium found in these patients. It is suggested that selenium-containing proteins are involved in thyroid hormonal synthesis, by protecting biosynthetic processes against the toxicity of free oxygen radicals.


Asunto(s)
Síndrome de Down/metabolismo , Hipotiroidismo/metabolismo , Selenio/sangre , Adulto , Estudios de Casos y Controles , Síndrome de Down/complicaciones , Femenino , Humanos , Discapacidad Intelectual/metabolismo , Masculino , Estrés Oxidativo , Glándula Tiroides/fisiología , Tirotropina/sangre , Tiroxina/sangre , Proteínas de Unión a Tiroxina/metabolismo , Zinc/sangre
8.
Analyst ; 123(1): 3-6, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9581011

RESUMEN

Rheumatoid arthritis (RA) is characterised by migration of activated phagocytes and other leukocytes into synovial and periarticular tissue. Activated oxygen species and other mediating substances from triggered phagocytes appear to exacerbate and perpetuate the rheumatoid condition. Iron excesses are capable of aggravating the arthritic inflammation, probably through their pro-oxidant potentials. In contrast, therapeutically given gold salts, through a lysosomal loading of the metal, inhibit the triggered cells, thereby reducing the toxic oxygen production. Pharmacological doses of zinc also may immobilise macrophages. Furthermore, the copper-zinc-containing enzyme SOD (superoxide dismutase) can act as a scavenger of toxic oxygen in the tissues. Therapeutic remission of RA has been obtained following intraarticular administration of SOD. Intramuscular administration of copper complexes has induced remission in about 60% of RA patients in open studies. Another drug, penicillamine, that protects cellular membranes against toxic oxygen in vitro, is presumed to act as an antirheumatic via the SOD mimetic activity of its copper complex. Thiomalate and other thiols may possess similar activities. Selenium compounds also may act as oxygen radical scavengers. A significant alleviation of articular pain and morning stiffness was obtained following selenium and vitamin E supplementation in a double-blind study on RA patients. The observations reviewed here indicate that metal compounds and other antioxidants can reduce the rheumatic inflammation by reducing the cellular production and/or concentration of toxic oxygen species.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Quelantes/uso terapéutico , Metales/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Artritis Reumatoide/metabolismo , Citosol/enzimología , Humanos , Metales/metabolismo , Superóxido Dismutasa/metabolismo
9.
Tidsskr Nor Laegeforen ; 118(7): 1064-6, 1998 Mar 10.
Artículo en Noruego | MEDLINE | ID: mdl-9531831

RESUMEN

Based upon recent research, bisphosphonates have now attained a ranking as the first alternative to oestrogen replacement therapy in women with postmenopausal osteoporosis. The efficacy of these drugs has been clearly documented in recent years, particularly as a result of extensive clinical trials with alendronate. The studies have also confirmed the favourable risk/benefit ratio. The specific affinity of bisphosphonates for bone tissue has been recognized for many years, and explains the diagnostic use of radio-labelled species in skeleton scintigraphy. Bisphosphonates deposited in bone tissue reverse the osteoporotic process by inhibiting osteoclastic bone resorption. This mechanism also explains their role as the treatment of choice in patients with Paget's disease and cancer induced hypercalcaemia. In addition, the same drugs are useful adjuvants in the treatment of patients with multiple myeloma or bone metastases to lessen the pain and risk of fracture. A possible role of bisphosphonates in the management of cancer patients without detectable bone metastases or patients with rheumatoid arthritis has been discussed, but further research is needed in these areas.


Asunto(s)
Difosfonatos/química , Difosfonatos/farmacología , Difosfonatos/uso terapéutico , Femenino , Humanos , Osteoporosis Posmenopáusica/prevención & control , Investigación
10.
Tidsskr Nor Laegeforen ; 118(1): 58-62, 1998 Jan 10.
Artículo en Noruego | MEDLINE | ID: mdl-9481913

RESUMEN

Inorganic mercury is absorbed in small amounts from dental amalgam fillings. Exposure can be calculated by measuring the level of mercury in the blood or urine (u-Hg). The average u-Hg in Norwegians is approximately 2-3 micrograms/g creatinine (approximately 1-2 nmol/mmol creatinine). Classic signs of mercury poisoning occur in a fraction of long-term exposed subjects with u-Hg > 100 micrograms/g creatinine (56 nmol/mmol creatinine). Subtle effects (e.g. enzymuria, altered selenium metabolism, and changes in tremor spectra) have been reported in humans at average levels of 20-35 micrograms/g creatinine (approximately 11-20 nmol/mmol creatinine). There is widespread concern about possible adverse effects of mercury from amalgam fillings. Data on exposure-response relationships make it less likely that low-level mercury exposure from amalgam fillings should cause symptoms or physical signs. Studies of the association between symptoms and amalgam fillings have been negative. Patients with symptoms allegedly caused by mercury from amalgam should undergo thorough medical examination. Based on the patient's symptoms and physical signs adequate time should be allowed for careful recording of medical history, physical examination and relevant laboratory tests.


Asunto(s)
Amalgama Dental/efectos adversos , Intoxicación por Mercurio/etiología , Mercurio/efectos adversos , Amalgama Dental/metabolismo , Humanos , Intoxicación por Mercurio/diagnóstico , Intoxicación por Mercurio/prevención & control , Medición de Riesgo
11.
Zhongguo Yao Li Xue Bao ; 19(3): 203-6, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-10375726

RESUMEN

AIM: To study the effects of epinephrine, homocysteine, and other complexing agents on the cytotoxicity of copper sulfate. METHODS: In vitro suspensions of human red cells incubated with cupric sulfate were used, and hemolysis was determined by extracellular hemoglobin. RESULTS: The hemolytic activity of CuSO4 (0.3 mmol.L-1) was enhanced by the presence of epinephrine and to a lesser extent by homocysteine, whereas D-penicillamine, succimer, and mercaptodextran reduced the copper-induced hemolysis. The latter 3 chelating thiols also reduced the copper-epinephrine-induced hemolysis. The plasma protein ceruloplasmin reduced markedly the copper-epinephrine-induced hemolysis, even upon concentrations < 20% of that of copper. Chromic chloride, as well, acted anti-hemolytically. CONCLUSION: The latter protectors may interact with the production or activity of toxic oxygen, while classical copper chelators sequester cupric ions from interaction with epinephrine or homocysteine.


Asunto(s)
Antídotos/toxicidad , Quelantes/farmacología , Sulfato de Cobre/toxicidad , Epinefrina/farmacología , Hemólisis/efectos de los fármacos , Adulto , Ceruloplasmina/farmacología , Sinergismo Farmacológico , Homocisteína/farmacología , Humanos , Penicilamina/farmacología , Succímero/farmacología
12.
J Appl Toxicol ; 17(5): 337-43, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9339747

RESUMEN

The object of this work was to investigate possible interactions of mercury, cadmium and selenium in humans. Selenium and cadmium in blood and urine were determined in this cross-sectional study of 130 males, of whom 77 had been previously exposed to mercury vapour at a chloralkali plant. Of the participants, 61.5% were smokers and 16.2% were never-smokers. The concentration of selenium in blood (B-Se) was significantly lower in subjects currently smoking more than 50 g of tobacco per week compared to never-smokers, whereas the concentration of cadmium in blood (B-Cd) was significantly higher in all categories of current smokers. In the multiple linear regression analysis, B-Se as a dependent variable was negatively associated with B-Cd, whereas current smoking habits were not included in the model as a predictor variable. In contrast, B-Cd as a dependent variable was positively associated with current as well as previous smoking habits, and negatively with both B-Se and the 'cumulative dose' of previous mercury vapour exposure. The concentration of selenium in blood was also negatively associated with B-Cd in the group of never-smokers (Spearman's r = -0.80; P < 0.001). In conclusion, these results suggest a depressive effect of cadmium on the concentration of selenium in blood, while smoking alone did not operate as a true predictor for this effect. Furthermore, previous exposure to mercury apparently modifies the concentration of cadmium in blood.


Asunto(s)
Cadmio/sangre , Cadmio/orina , Mercurio/efectos adversos , Selenio/sangre , Selenio/orina , Fumar/efectos adversos , Adulto , Estudios Transversales , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Exposición Profesional , Análisis de Regresión
13.
Scand J Gastroenterol ; 30(12): 1200-3, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9053974

RESUMEN

BACKGROUND: Previous studies have suggested abnormal copper metabolism in patients with primary sclerosing cholangitis (PSC). In the present work the trace element metabolism was studied in a group of 32 patients with PSC. METHODS: Hepatic copper and selenium concentrations were determined with a sensitive electrothermal atomic absorption technique. Serum concentrations of copper and zinc were determined by conventional atomic absorption. RESULTS: For the patient group serum copper values (20.3 +/- 4.5 mumol/l) were higher than those for the control group (14 +/- 3 mumol/l), and average hepatic copper concentrations were greater by a factor of four. Serum selenium values were slightly lower, although the average hepatic selenium was significantly higher than in the healthy control group. Previous studies have discussed possible toxic effects of hepatocellular copper accumulation, which may be accompanied by formation of activated oxygen species and depletion of glutathione. In the present study, however, it could not be demonstrated that the concentration of the lipoperoxidation product, malonic dialdehyde, was higher than normal in blood. Furthermore, blood concentrations of glutathione and glutathione peroxidase were not abnormal. CONCLUSION: Although a protective effect of the raised selenium concentrations in the liver might be discussed, it is apparent that the copper accumulation in the liver cells described here did not induce detectable changes in the indices studied.


Asunto(s)
Colangitis Esclerosante/metabolismo , Colangitis Esclerosante/patología , Cobre/análisis , Cobre/metabolismo , Selenio/análisis , Selenio/metabolismo , Adolescente , Adulto , Fosfatasa Alcalina/sangre , Estudios de Casos y Controles , Femenino , Glutatión/sangre , Humanos , Masculino , Persona de Mediana Edad
14.
Analyst ; 120(3): 779-81, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7741228

RESUMEN

The increasing use of thallium-201 (201Tl) in myocardial imaging studies during the last two decades, has justified a re-examination of the metabolism of this metal compound. It was found that about 4% of an injected dose was rapidly distributed to the healthy human myocardium, which is in agreement with previous reports. Apparent similarities exist between the transport of ionic thallium and potassium through cell membranes. Upon clinical use, myocardial perfusion scintigraphy is routinely carried out after i.v. administration of the agent. It is generally accepted that the rapid myocardial extraction of circulating 201Tl, during the initial 30 min. depends upon an unimpaired blood perfusion; whereas the prolonged uptake/redistribution during the next 3 h reflects myocardial viability. In the present paper, the reliability of 201Tl scintigraphy to disclose insufficient myocardial perfusion is illustrated by the examination of biological samples from patients, that were also studied by the classical coronary angiographic technique, the two methods showed an acceptable degree of agreement.


Asunto(s)
Corazón/diagnóstico por imagen , Radioisótopos de Talio , Humanos , Miocardio/metabolismo , Especificidad de Órganos , Perfusión , Cintigrafía , Estudios Retrospectivos , Radioisótopos de Talio/farmacocinética
16.
Analyst ; 120(3): 931-3, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7741257

RESUMEN

The transport of [51Cr]chromate into human erythrocytes and isolated rat hepatocytes has been investigated. It was found that uptake in both cell types could be inhibited by the established anion carrier inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid. The uptake was very fast, and in kinetic studies a very low Km was found for both cell types, indicating either a high affinity of chromate for the carrier, and/or, more probably, an efficient intracellular reduction and trapping of 51Cr. The transport capacity, however, was of the same magnitude as for physiological substrates, such as lactate and sulfate. The uptake was temperature dependent and the activation energy was of the same magnitude as that for the physiological substrates. The uptake could be partly inhibited by high levels (mmol l-1) of lactate, pyruvate or sulfate. The uptake rate was greatly increased at lower pH (6.0 versus 7.4) which could indicate transport of the HCrO4- form or an increased intracellular rate of CrVI reduction. The results showed efficient uptake of 51CrO4(2-) by erythrocytes and hepatocytes. They were consistent with a mechanism of uptake which involved the cell membrane anion-exchange carrier in the transport and trapping of 51Cr within the cell.


Asunto(s)
Antiportadores/metabolismo , Cromatos/sangre , Eritrocitos/metabolismo , Hígado/metabolismo , Ácido 4,4'-Diisotiocianostilbeno-2,2'-Disulfónico/farmacología , Animales , Antiportadores/antagonistas & inhibidores , Transporte Biológico , Radioisótopos de Cromo , Humanos , Cinética , Ratas
17.
Tidsskr Nor Laegeforen ; 115(1): 43-4, 1995 Jan 10.
Artículo en Noruego | MEDLINE | ID: mdl-7846659

RESUMEN

A 27 year old woman suffered from recurrent attacks of laryngeal oedema due to C1-inhibitor deficiency, and was treated with danazol and tranexamic acid. The trachea was intubated with great difficulty, twice on one occasion. Two and a half years later she was admitted to the Intensive Care Unit with dyspnoea and dysphagia. Tranexamic acid, corticosteroids, adrenaline (also inhalated), were administered intravenously, but dyspnoea progressed. During preparation for tracheostomy the patient suffered from sudden airway collapse. Attempts to ventilate by mask, puncture of the cricothyroid membrane and intubation were unsuccessful. A small tube was eventually inserted into the trachea after four minutes. The patient was then severely cyanotic with a pulse of thirty, and had dilated pupils. The next morning convulsions ensued and a CT scan showed cerebral oedema. In spite of treatment with pentothal, mannitol and hyperventilation she died. The authors advocate the use of intravenous infusion of C1-inhibitor concentrate, since traditional treatment is inadequate. Persons with hereditary angio-oedema should have a personal supply of C1-inhibitor at hand.


Asunto(s)
Angioedema/genética , Edema Laríngeo/genética , Adulto , Angioedema/tratamiento farmacológico , Resultado Fatal , Femenino , Humanos , Edema Laríngeo/tratamiento farmacológico , Noruega
18.
Pharmacol Toxicol ; 70(4): 308-13, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1608917

RESUMEN

The mercury concentrations in blood (HgB) and urine (HgU) samples, and in exhaled air (HgAir) were measured in 147 individuals from an urban Norwegian population, using cold vapour atomic absorption spectrometry. The study aimed to estimate the mercury exposure from the dental restorations, by correlating the data to the presence of amalgam restorations. Mean values were HgB = 24.8 nmol/l, HgU = 17.5 nmol/l and HgAir = 0.8 micrograms/m3. HgU correlated with HgAir, and both HgU and HgAir with the number of amalgam restorations, amalgam restored surfaces and amalgam restored occlusal surfaces. HgB showed poor correlation to HgU and HgAir and the presence of amalgam restorations. A differentiation of the mercury absorption due to exposure from dental amalgams and from the dietary intake, necessitates measurements of both organic and inorganic mercury in the plasma, and in the erythrocytes. The results suggest that individuals with many amalgam restorations, i.e., more than 36 restored surfaces, absorb 10-12 micrograms Hg/day.


Asunto(s)
Amalgama Dental/farmacocinética , Mercurio/metabolismo , Adolescente , Adulto , Anciano , Aire/análisis , Niño , Preescolar , Femenino , Humanos , Masculino , Mercurio/sangre , Mercurio/orina , Persona de Mediana Edad
20.
Arctic Med Res ; 50(3): 103-6, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1883416

RESUMEN

This study investigated the relationship of serum selenium to its dietary sources in a group of Lappish men and a control population. Lappish men had higher serum selenium concentrations than non-Lappish men (1.79 vs 1.58 mumol/1; p = 0.003). Serum selenium correlated positively with consumption of reindeer meat, age and cholesterol. In linear regression models, however, being Lappish was the most significant predictor of high serum selenium. Lappish men ate more reindeer meat (p = 0.001) and less fish (p = 0.013) than men in the control group. Consumption of reindeer meat was also correlated with higher serum cholesterol levels. We conclude that high serum selenium concentrations in Lappish men may be important since low mortality from cancer is reported in this group.


Asunto(s)
Dieta , Reno , Selenio/sangre , Adulto , Animales , Colesterol/sangre , Humanos , Masculino , Carne , Persona de Mediana Edad , Ocupaciones , Países Escandinavos y Nórdicos
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