RESUMEN
The ICD classification does not provide the opportunity to adequately identify pain patients. Therefore we developed an alternative method for the identification and classification of pain patients which is based on prescription and diagnoses data from the year 2006 of one nationwide sickness fund (DAK) and which is led by two main assumptions: 1. Beneficiaries without prescription of an analgetic drug but with a diagnosis pattern that is characteristic of patients who are treated with opioids are also likely to be pain patients. 2. Each combination of diagnosis groups can be traced back to one primary diagnosis out of a diagnosis group according to the patient classification system CCS (Clinical Classifications Software). The selection of this diagnosis group (CCS) allows for the allocation of the beneficiary to only one pain type. As a result we identified 65 combinations of CCS diagnosis groups--aggregated to nine "CCS pain types"--to which 77.1% of all patients with at least two opioid prescriptions can be allocated: 26.3% to pain due to arthrosis, 18.0% to pain due to intervertebral disc illnesses, 13.1% to other specific back pain, 6.7% to neuropathic pain, 4.5% to unspecific back pain, 4.2% to headache, 2.4% to pain after traumatic fractures, 1.3% to pain of multimorbid, high-maintenance patients, and 0.6% to cancer pain. Based on our method beneficiaries who have a high probability of suffering from moderate to strong pain can be identified and included in further claims data analyses of health care delivery and utilization pattern of pain-related disorders in Germany.
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Grupos Diagnósticos Relacionados/economía , Asignación de Recursos para la Atención de Salud/economía , Clasificación Internacional de Enfermedades , Programas Nacionales de Salud/economía , Dolor/clasificación , Dolor/economía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/economía , Analgésicos Opioides/uso terapéutico , Enfermedad Crónica , Control de Costos/economía , Atención a la Salud/economía , Alemania , Humanos , Revisión de Utilización de Seguros , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/tratamiento farmacológico , Adulto JovenRESUMEN
BACKGROUND: Patients with end-stage renal disease are at high risk from premature death due mainly to cardiovascular disease and infections. Established risk factors do not sufficiently explain this increased mortality. We, therefore, investigated total mortality prospectively in a single-centre study in patients on hemodialysis and assessed the prognostic value of baseline disease status, laboratory variables including emerging risk factors, and the influence of vitamin treatment. METHODS: Patients (n = 102) were followed-up for 4 years or until death (n = 49). Survival was calculated by the Kaplan-Meier method. Cox-proportional hazards model was used to determine independent predictors of total mortality. RESULTS: The known risk factors age, baseline clinical atherosclerotic disease, low albumin and increased cardiac troponin T were significantly associated with mortality. Patients who received multivitamins during follow-up had a significantly lower mortality risk than those not receiving this treatment (hazard ratio 0.29, 95% confidence interval 0.15-0.56). These associations remained significant after adjustment for age, cardiovascular disease, albumin and cardiac troponin T at baseline. CONCLUSIONS: The present study suggests that multivitamin supplementation in patients with end-stage renal disease is closely associated with reduced mortality due to all causes. These observations have to be validated in randomized clinical intervention trials.
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Fallo Renal Crónico/mortalidad , Vitaminas/administración & dosificación , Anciano , Distribución de Chi-Cuadrado , Femenino , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Diálisis Renal , Factores de Riesgo , Estadísticas no Paramétricas , Análisis de SupervivenciaRESUMEN
Functional C(-260)--> T polymorphism in the promoter of the CD14 gene has been reported to be associated with coronary heart disease (CHD). The functional role of the polymorphism, however, is still a matter of debate, since several studies have not proved its effect on clinical outcomes associated with atherosclerosis. Cardiovascular-related morbidity and mortality was assessed in a post-hoc approach four years after baseline characterization of patients (male/female n = 36/32) with angiographically proven coronary heart disease. CD14 C(-260)--> T promoter genotype was determined at baseline. Seventeen out of 20 CHD patients with non-lethal cardiovascular events carried at least one T-allele. CD14 T-260 allele carriers have a 3.59-fold (95 % confidence interval: 1.11-6.75) increased risk for non-lethal cardiovascular events (Kaplan-Meier plot: log rank test p = 0.029). All patients with lethal outcomes (n = 6) were also T-allele carriers. Multivariate logistic regression analysis among CHD patients including age, established risk factors and the C(-260)--> T polymorphism as covariates and non-lethal events as a dependent variable confirmed the independent prospective effect of the T-allele on cardiovascular outcomes in this subset. Further evidence is provided for the role of CD14 C(-260)--> T promoter polymorphism as a genetic susceptibility marker of atherosclerosis in patients with an advanced clinical course of the disease. Due to the small sample size and post-hoc character of the study large-scale prospective studies that monitor patients with proven CHD are needed to confirm these findings.
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Enfermedad Coronaria/genética , Receptores de Lipopolisacáridos/genética , Regiones Promotoras Genéticas/genética , Anciano , Biomarcadores , Enfermedad Coronaria/epidemiología , ADN/biosíntesis , ADN/genética , Femenino , Genética , Genotipo , Humanos , Lípidos/sangre , Modelos Logísticos , Masculino , Persona de Mediana Edad , Polimorfismo Genético/genética , RiesgoRESUMEN
The present study in the South American rodent Octodon degus shows for the first time that the postnatal development of hypothalamic-pituitary-adrenal axis function in this semi-precocial species differs from that of altricial rodents, i.e. rats or mice, in several aspects. Our experiments revealed a particular pattern of hypothalamic-pituitary-adrenal axis activity during the first 3 weeks of life characterized by (i) a period of low plasma glucocorticoid concentrations, during which (ii) brief stress exposure (1 h parental separation) is able to elevate glucocorticoids significantly. In addition, (iii) repeated stress exposure (1 h parental separation daily) during the first 3 weeks of life resulted in females, but not in males, in an attenuated separation-induced increase of glucocorticoids, and a higher behavioural activity in both sexes at postnatal day 21. These data indicate that parental separation early in life acts as a 'strong' stressor in this species, which on the long run can alter endocrine stress response at the time of weaning in a sex-specific manner. These findings support the role of the hypothalamic-pituitary-adrenal axis as one of the key factors mediating the effects of early life stress on the neuronal network and behaviour in O. degus.
Asunto(s)
Conducta Animal/fisiología , Corticosterona/sangre , Hidrocortisona/sangre , Octodon/fisiología , Aislamiento Social/psicología , Estrés Psicológico/sangre , Enfermedad Aguda , Adaptación Fisiológica , Adaptación Psicológica , Factores de Edad , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Padre , Femenino , Glucocorticoides/sangre , Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipotálamo-Hipofisario/fisiopatología , Masculino , Madres , Octodon/psicología , Sistema Hipófiso-Suprarrenal/fisiología , Sistema Hipófiso-Suprarrenal/fisiopatología , Factores Sexuales , Medio SocialRESUMEN
BA-HAN-1C is a clonal rat rhabdomyosarcoma cell line composed of proliferating mononuclear cells, which partly fuse to terminally differentiated postmitotic myotube-like giant cells. The exposure to retinoic acid in vitro resulted in time- and dose-dependent changes of both cell differentiation and cell growth. The mononuclear cells revealed bundles of newly formed thick and thin myofilaments, never observed in untreated cultures, and exhibited signs of contact inhibition. In addition, there was a statistically significant increase (P less than 0.001) in the number of terminally differentiated postmitotic myotube-like giant cells and in the creatine kinase activity (P less than 0.05) which was used as a biochemical differentiation marker. At the same time cell growth was significantly inhibited (P less than 0.001) in vitro and a decrease in plating efficiency, as well as in saturation density, was observed. These data demonstrate that retinoic acid can suppress cell growth and simultaneously initiate differentiation in a malignant mesenchymal tumor cell line. However, despite the clonal nature of BA-HAN-1C, the complete status of terminal differentiation was not achieved by all tumor cells. The reason why not all tumor cells responded to retinoic acid is unknown at the present time and will have to be the subject of further studies.
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Rabdomiosarcoma/patología , Tretinoina/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Fusión Celular , Línea Celular , Creatina Quinasa/metabolismo , Microscopía Electrónica , RatasRESUMEN
Three clonal subpopulations (A, B, C) isolated from the same rhabdomyosarcoma of the rat were tested and compared for their susceptibility to differentiation induction using retinoic acid (RA), dimethylformamide (DMF), and N-monomethylformamide (NMF). These subpopulations differ in that a block to spontaneous differentiation is imposed at different stages which are characteristic for each subpopulation. Whereas tumor cell proliferation was significantly inhibited (P less than 0.001) in all three subpopulations, the effects of RA, DMF, and NMF on tumor cell differentiation were strikingly heterogeneous. The response was most marked in subpopulation C, as evidenced by a significant increase in the number of terminally differentiated myotube-like giant cells (P less than 0.001) and in biochemical differentiation, as indicated by the creatine kinase activity (P less than 0.05). Between 5% (DMF and NMF) and 30% (RA) of the mononuclear cells in subpopulation C exhibited thick and thin myofilaments, which were never observed in the mononuclear cells of the control. In contrast, subpopulation A and B responded to RA, DMF, and NMF quite heterogeneously with an increase in biochemical differentiation, whereas terminally differentiated myotube-like giant cells were never observed. These results demonstrate that the therapeutic potential of differentiation induction in malignant tumors may be impaired by tumor heterogeneity.
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Dimetilformamida/farmacología , Formamidas/farmacología , Rabdomiosarcoma/patología , Tretinoina/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Fusión Celular/efectos de los fármacos , Células Clonales , Creatina Quinasa/metabolismo , Isoenzimas , Ratas , Células Tumorales CultivadasRESUMEN
The hepatic clearance of triglyceride-rich lipoproteins is mediated via apolipoprotein (apo) E which occurs in three common isoforms, apoE2, apoE3 and apoE4. To study the importance of the apoE isoforms on the response curves of different triglyceride-rich lipoproteins and the effect of chylomicron remnants on the composition of HDL, 37 normolipemics were investigated after a standardized fatty meal (8 apoE2/E2, 8 apoE2/E3, 8 apoE3/E3, 7 apoE3/E4 and 6 apoE4/E4). These individuals were matched for age, body mass index, fasting triglycerides, HDL-cholesterol, and apoA-I. A delayed chylomicron remnant clearance was observed only in apoE2 homozygotes, and this delay was neither correlated with fasting lip ds nor with peak lipoprotein concentrations. In apoE2/E3 heterozygotes, in contrast, the defective isoform E2 appears to be compensated for by the normal apoE isoform E3. In non-apo-E2/E2 individuals, the chylomicron remnant response was highly correlated with the magnitude of chylomicron and VLDL responses, with fasting triglycerides, and with the triglycerides enrichment and cholesterol depletion of HDL. These correlations were not observed in apoE2/E2. From these results we conclude that the chylomicron remnant response curve is an indicator of the extent of postprandial lipemia in non-apoE2/E2 individuals only.
Asunto(s)
Apolipoproteínas E/clasificación , Quilomicrones/farmacocinética , Grasas de la Dieta/farmacocinética , Periodo Posprandial/fisiología , Triglicéridos/farmacocinética , Adulto , Apolipoproteínas E/sangre , Área Bajo la Curva , Ayuno/sangre , Femenino , Humanos , Lipoproteínas HDL/química , Masculino , Tasa de Depuración Metabólica , Fenotipo , Retinoides/sangreRESUMEN
High-density lipoprotein (HDL) was fractionated by preparative isoelectric focussing into six distinct subpopulations. The major difference between the subfractions was in the molar ratio of apolipoprotein A-I to apolipoprotein A-II, ranging from 2.1 to 0.5. The least acidic particles had little apolipoprotein A-II, were larger and contained the most lipid. The efflux capacity of the HDL subfractions was tested with mouse peritoneal macrophages and a mouse macrophage cell line (P388D1), either fed with acetylated low-density lipoprotein or free cholesterol. All the HDL subfractions were equally able to efflux cholesterol. The efflux was concentration dependant and linear for the first 6 h. The HDL subfractions bound with high affinity (Kd = 6.7-7.9 micrograms/ml) at 4 degrees C to the cell surface of P388D1 cells (211,000-359,000 sites/cell). Ligand blotting showed that all the HDL subfractions bound to membrane polypeptides at 60, 100, and 210 kDa. These HDL binding proteins may represent HDL receptors. In summary HDL particles, which differed principally in ratio of apolipoprotein A-I to apolipoprotein A-II behaved in a similar manner for both cholesterol efflux and cell surface binding.
Asunto(s)
Apolipoproteína A-II/análisis , Apolipoproteína A-I/análisis , Colesterol/metabolismo , Lipoproteínas HDL/farmacología , Macrófagos/metabolismo , Animales , Apolipoproteína A-I/metabolismo , Apolipoproteína A-I/farmacología , Apolipoproteína A-II/metabolismo , Apolipoproteína A-II/farmacología , Línea Celular , Membrana Celular/metabolismo , Ésteres del Colesterol/metabolismo , Ditiotreitol/farmacología , Humanos , Focalización Isoeléctrica , Cinética , Lipoproteínas HDL/aislamiento & purificación , Lipoproteínas HDL/metabolismo , Lipoproteínas HDL3 , Lipoproteínas LDL/farmacología , Macrófagos/efectos de los fármacos , Ratones , Cavidad Peritoneal/citologíaRESUMEN
BACKGROUND: Patients with end-stage renal disease have a high risk of premature death, mainly as the result of cardiovascular disease (CVD), which is not sufficiently explained by the conventional risk factors. We therefore prospectively investigated total mortality and cardiovascular events in 102 patients on hemodialysis and assessed the prognostic value of baseline disease status and laboratory variables including total homocysteine and cardiac troponin T. METHODS AND RESULTS: Patients were followed for 2 years or until their first event of CVD (for outcome variable cardiovascular events, n=33) or death (for outcome variable total mortality, n=28). Survival was computed by the Kaplan-Meier method. Cox proportional hazards model was used to determine independent predictors of CVD events or total mortality. Cardiac troponin T emerged as the most powerful predictor of mortality, resulting in an almost 7-fold risk increase at concentrations >0.10 ng/mL (hazard ratio 6.85, 95% CI 3. 04 to 15.45). Total homocysteine level greater than median was also associated with mortality (hazard ratio 2.44, 95% CI 1.10 to 5.40). These hazard ratios did not change substantially after adjustment for other risk factors. Significant predictors for CVD events were baseline diabetes, cerebrovascular disease, serum glucose, and triglycerides. After adjustment, only glucose and triglycerides remained significantly related to CVD events (hazard ratio with 95% CI 1.33 [1.12 to 1.57] and 1.14 [1.04 to 1.26], respectively, for a 1-mmol/L increase in concentration). CONCLUSIONS: We conclude that total homocysteine and particularly cardiac troponin T are important predictors of mortality in patients with end-stage renal disease, whereas other laboratory variables and baseline disease status have less prognostic value.
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Fallo Renal Crónico/sangre , Fallo Renal Crónico/mortalidad , Troponina T/sangre , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/diagnóstico , Complicaciones de la Diabetes , Diabetes Mellitus/diagnóstico , Femenino , Estudios de Seguimiento , Homocisteína/sangre , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/diagnóstico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Sensibilidad y Especificidad , Tasa de SupervivenciaRESUMEN
OBJECTIVES: The diagnostic importance of circulating solubilized tumor necrosis factor-alpha receptor II (sTNF-alphaRII) and interleukin-2 receptor in coronary heart disease (CHD) was evaluated. In addition, these variables were correlated with solubilized adhesion molecule levels (i.e., intracellular adhesion molecule [ICAM], vascular cell adhesion molecule [VCAM], and E-selectin). BACKGROUND: Atherosclerosis is considered to be a chronic inflammatory process. Because the immunologic network presents an abundance of positive and negative feedback mechanisms, information obtained from different immunologic variables might be highly redundant. METHODS: In a cross-sectional study design, 60 patients with angiographically proven CHD were compared with 60 individuals who had undergone coronary angiography but in whom no evidence of stenosis could be found (control subjects). Angiography was performed at least one year before the study. Cytokine levels were determined by enzyme-linked immunosorbent assay technique and evaluated by univariate and multivariate statistical methods. RESULTS: All immunologic variables except E-selectin (p = 0.08) significantly discriminated between patients and control subjects. Coronary artery bypass graft surgery after angiography did not lead to significant differences in the variables investigated in the patients with bypass surgery as compared with the subjects without bypass surgery. Receiver-operating characteristics analysis showed comparable test accuracy for solubilized adhesion molecules and cytokine receptors. Multivariate logistic regression analysis, including age, revealed that only ICAM and sTNF-alphaRII were independently correlated with the presence of CHD. Patients belonging to the third tertile of at least one of these two variables demonstrated a 1.6- to 2-fold increased relative risk for the presence of CHD. CONCLUSIONS: We concluded that both circulating ICAM and TNF-alphaRII should be further evaluated as markers for atherosclerotic changes in the coronary system.
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Moléculas de Adhesión Celular/sangre , Enfermedad Coronaria/sangre , Receptores de Citocinas/sangre , Adulto , Anciano , Antígenos CD/sangre , Biomarcadores/sangre , Angiografía Coronaria , Puente de Arteria Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/cirugía , Estudios Transversales , Selectina E/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Receptores de Interleucina-2/sangre , Receptores del Factor de Necrosis Tumoral/sangre , Receptores Tipo II del Factor de Necrosis Tumoral , Factores de Riesgo , Molécula 1 de Adhesión Celular Vascular/sangreRESUMEN
OBJECTIVE: Smaller LDL particles are associated with an increased risk for coronary artery disease and have been found predominantly in subjects with the insulin resistance syndrome. Although insulin resistance has been suggested to be a basic defect, little is known about the relation between this predisposing factor (and associated metabolic disturbances) and LDL size distribution in young and metabolically healthy subjects. In the present study, we investigated the relation between insulin sensitivity, lipoprotein distribution, and LDL patterns in young adults to increase the understanding of the development of metabolic risk factors in an early phase of the life span. RESEARCH DESIGN AND METHODS: Young, clinically healthy subjects (n = 50; age 21.1-30.6 years) were enrolled in the study. Glucose metabolism was characterized by peripheral insulin sensitivity assessed by a hyperinsulinemic-euglycemic clamp and by levels of fasting insulin, C-peptide, and glucose. Lipoproteins were measured, and LDL fractions were additionally characterized by the diameter of the major LDL peak, estimated by 2-16% polyacrylamide gradient gel electrophoresis. Cholesterol ester transfer was estimated with a fluorescent spectroscopic method that measures the transfer of fluorescent cholesteryl linoleate between exogenous donor and acceptor particles. In this assay system, cholesterylester transfer protein (CETP) activity was only influenced by the plasma CETP concentration therefore reflecting more likely the CETP mass. RESULTS: In the entire study group, 47 subjects had LDL phenotype A (LDL diameter > 25.75 nm) and 3 subjects had an intermediate phenotype (25.50-25.75 nm). An interrelation between LDL size and LDL triglyceride (LDL-TG) per apolipoprotein (apo) B (Spearman's rank correlation analysis; r = -0.78; P < 0.001) or LDL cholesterol ester (CE) per apoB (r = 0.58, P < 0.001) was found, and 39% of the plasma samples studied were characterized by a monodispersed LDL pattern. Furthermore, LDL diameters correlated negatively with total TGs (men: r = -0.52, P < 0.001; women: r = -0.61, P < 0.001) and positively with insulin sensitivity (total population: r = 0.54, P < 0.001). In addition, LDL size was inversely related to the [VLDL + LDL cholesterol (CH)]/HDL-CH ratio and positively to the HDL-CE/TG ratio, which were both related vice versa to CETP activity levels. A direct relation between CETP activity levels and LDL size or composition was not observed. In a linear regression analysis including parameters of lipoprotein metabolism (TG, HDL cholesterol, CETP activity level), glucose metabolism (insulin sensitivity, fasting insulin), and sex, only TGs predicted significantly for 62% of LDL size variability. If the total study population was evaluated according to quintiles of insulin sensitivity, increasing TGs (analysis of variance, Scheffé test; P < 0.05) and CETP activity levels (P < 0.05) were combined with decreasing LDL particle diameters (P < 0.05) and with a preponderance of a monodispersed LDL pattern (60%) in the most insulin-resistant group. CONCLUSIONS: Among parameters of the lipoprotein and glucose metabolism, total TG is the single most important factor affecting LDL size variability, even in young adults. If the study population is evaluated according to insulin sensitivity, lipoprotein pattern is altered in a more atherogenic manner in the most insulin-resistant subjects. In this group, increasing TG and CETP activity levels are associated with decreasing LDL particle diameters and preponderance of a monodispersed LDL pattern. Although increasing CETP levels are combined with this particular lipoprotein profile, a direct relation to LDL size and composition is not found.
Asunto(s)
Composición Corporal , Glicoproteínas , Lipoproteínas LDL/sangre , Lipoproteínas/sangre , Adulto , Proteínas Portadoras/sangre , Proteínas de Transferencia de Ésteres de Colesterol , Ésteres del Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , VLDL-Colesterol/sangre , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Resistencia a la Insulina , Masculino , Valores de Referencia , Caracteres Sexuales , Triglicéridos/sangreRESUMEN
BACKGROUND: n-3 Fatty acids lower plasma triacylglycerols not only in the fasting state but also in the postprandial state. However, it is not known whether chylomicrons, chylomicron remnants, and VLDLs are all affected equally or whether some lipoprotein species are lowered preferentially. OBJECTIVE: Lipoproteins, including large and small chylomicron remnants, were determined specifically with the aid of a newly developed method involving a combination of size-exclusion chromatography and fluorometric determination of retinyl palmitate, which served as a marker for exogenous fat. DESIGN: Twelve hypertriacylglycerolemic men were treated for 6 wk with 4 capsules containing 85% fish-oil concentrate/d; each capsule contained 850 mg n-3 fatty acid ethyl esters (49.1% eicosapentaenoic acid by wt and 32.2% docosahexaenoic acid by wt). Oral-fat-tolerance tests were performed before and after the treatment. Blood samples were drawn in the fasting state and until 8 h postprandially. RESULTS: Treatment with n-3 fatty acids reduced the fasting VLDL-triacylglycerol concentration by 44% (P < 0.05) and postprandial chylomicrons and VLDLs at 4, 6, and 8 h (P < 0.05) by 49-64% and 36-43%, respectively. Chylomicron remnants were reduced only in the late postprandial phase: large chylomicron remnants by 19% at 6 h and by 43% at 8 h (P < 0.05) and small chylomicron remnants by 31% at 8 h (P < 0.05). CONCLUSION: n-3 Fatty acids effectively lower chylomicrons and VLDLs, but their effect on chylomicron remnants was observed only in the late postprandial phase.
Asunto(s)
Quilomicrones/sangre , Ácidos Grasos Omega-3/uso terapéutico , Alimentos , Hipertrigliceridemia/sangre , Lipoproteínas VLDL/sangre , Adulto , Cromatografía en Gel , Diterpenos , Ayuno , Fluorescencia , Humanos , Hipertrigliceridemia/tratamiento farmacológico , Lipoproteína Lipasa/sangre , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Ésteres de Retinilo , Triglicéridos/sangre , Vitamina A/análogos & derivados , Vitamina A/sangreRESUMEN
Elevated homocysteine concentrations are a risk factor for atherosclerotic disease. Recently it was reported that lipid lowering with fibrates increases homocysteine by up to 40%. Since elevated homocysteine concentrations can readily be lowered by vitamin supplementation, a randomized, double-blind crossover study was performed to investigate the effect of fenofibrate plus folic acid, vitamin B6 and B12 versus fenofibrate plus placebo in hyperlipidemic men. The crossover study comprised a run-in period of 6 weeks, a first treatment phase of 6 weeks, a washout phase of 8 weeks and a second treatment phase of 6 weeks. Vitamins were given at doses of 650 microg folic acid, 50 microg vitamin B12 and 5 mg vitamin B6 per day for a period of 6 weeks. After fenofibrate plus placebo the increase in homocysteine concentration was 44+/-47%. After fenofibrate plus vitamins it was 13+/-25%, being significantly lower than without vitamins. The increase in homocysteine in response to fenofibrate may counteract the cardioprotective effect of lipid lowering. The addition of vitamins involved in homocysteine metabolism can prevent most of the homocysteine increase seen after fenofibrate plus placebo. Addition of these vitamins to fenofibrate may therefore be warranted for routine use.
Asunto(s)
Fenofibrato/efectos adversos , Homocisteína/sangre , Hiperlipidemias/sangre , Hipolipemiantes/efectos adversos , Vitaminas/administración & dosificación , Estudios Cruzados , Método Doble Ciego , Fenofibrato/uso terapéutico , Ácido Fólico/administración & dosificación , Humanos , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Masculino , Persona de Mediana Edad , Piridoxina/administración & dosificación , Vitamina B 12/administración & dosificaciónRESUMEN
Interestingly, plasma total homocysteine (tHcy) concentration is consistently higher in men than in women. This observation deserves further investigations because elevated tHcy concentrations have been shown to be independently associated with coronary, peripheral, and cerebral vascular diseases. It was the aim of the present study to define major determinants of plasma tHcy in a healthy middle-aged German population under particular consideration of the gender factor. The study population was obtained from an ongoing recruitment procedure for a cohort study and comprised 336 men and women, aged 40 to 65 years. Exclusion criteria were elevated creatinine levels in blood, history of skin or atherosclerotic diseases, current use of vitamins or other supplements, and heavy smoking. Plasma tHcy, folate, vitamin B12, vitamin B6, creatinine, testosterone and estradiol, protein, and hematocrit were measured. Fat-free mass was assessed by skinfold thickness. The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR), a key enzyme of folate and homocysteine metabolism, was determined by polymerase chain reaction (PCR) with restriction enzyme analysis. In this population, plasma tHcy ranged from 5 to 46 micromol/L. The frequency of the T allele of the MTHFR was 0.29, which is lower than in other populations. A total of 54.2% of this population was homozygote for the wild-type, 39.6% heterozygote, and 6.2% homozygote for the mutation. tHcy correlated negatively with folate and cobalamin concentration in blood and positively with creatinine. No correlation was seen with vitamin B6. From the gender-related variables, tHyc correlated significantly with fat-free mass and testosterone and inversely with estradiol. The difference between gender with regard to tHcy was mainly explained by differences in fat-free mass, but also by estradiol concentrations. The following contributions to the variation of tHcy were seen in a multivariate regression model: plasma cobalamin (11%), creatinine (11%), plasma folate (8%), fat-free mass (5%), estradiol (2%), MTHFR polymorphisms (2%), and plasma protein (1%). We concluded that tHcy in the general population has a variety of determinants ranging from nutrition, internal metabolic parameters to gender-related variables.
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Homocisteína/sangre , Neoplasias/etiología , Fenómenos Fisiológicos de la Nutrición , Adulto , Factores de Edad , Anciano , Análisis de Varianza , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Ácido Fólico/sangre , Alemania , Hormonas Esteroides Gonadales/sangre , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Factores Sexuales , Vitamina B 12/sangreRESUMEN
Hyperhomocysteinemia is frequently found in patients with end-stage renal disease (ESRD). Plasma total homocysteine (tHcy) concentrations may be reduced by supplementation with folic acid or combinations of folic acid, vitamin B12, and vitamin B6. Supplementation studies with vitamin B12 alone in patients with ESRD have not yet been published. In this study, we investigated the effects of intravenous injection of cyanocobalamin (1 mg/wk for 4 weeks) in ESRD patients (N = 14) with low serum cobalamin concentrations (<180 pmol/L). All patients had elevated levels of plasma tHcy, methylmalonic acid (MMA), and cystathionine before supplementation. After supplementation, plasma tHcy and MMA decreased 35% and 48%, respectively; however, cystathionine levels were unchanged. The extent of the plasma tHcy reduction tended to be influenced by the C677T polymorphism of methylenetetrahydrofolate reductase (MTHFR). Serum cobalamin increased significantly upon supplementation, whereas serum folate levels were substantially reduced by 47%. In contrast, red blood cell (RBC) folate was unchanged. This study shows that vitamin B12 supplementation effectively decreases both MMA and plasma tHcy in ESRD patients with low B12 levels. Furthermore, it illustrates the close interrelation between vitamin B12 and folate metabolism.
Asunto(s)
Antagonistas del Ácido Fólico/uso terapéutico , Ácido Fólico/sangre , Homocisteína/sangre , Fallo Renal Crónico/sangre , Fallo Renal Crónico/tratamiento farmacológico , Ácido Metilmalónico/sangre , Vitamina B 12/uso terapéutico , Adulto , Anciano , Suplementos Dietéticos , Femenino , Antagonistas del Ácido Fólico/administración & dosificación , Genotipo , Homocisteína/antagonistas & inhibidores , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Ácido Metilmalónico/antagonistas & inhibidores , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Vitamina B 12/administración & dosificación , Vitamina B 12/sangreRESUMEN
BACKGROUND: A new extended-release (ER) formulation of fluvastatin 80 mg has been developed for once-daily treatment of primary hypercholesterolemia. OBJECTIVE: The purpose of this study was to compare the lipid-lowering efficacy and tolerability of fluvastatin ER (80 mg once daily) versus fluvastatin immediate-release (IR) (40 mg once or twice daily). METHODS: Following a 4-week placebo/dietary run-in period, patients with primary hypercholesterolemia type IIa or IIb (low-density lipoprotein cholesterol ILDL-C] > or = 160 mg/dL and triglycerides [TG] < or = 400 mg/dL) were randomized (2:1:1) to receive fluvastatin ER 80 mg once daily at bedtime (QPM), fluvastatin IR 40 mg QPM, or fluvastatin IR 40 mg BID for 24 weeks. Patients who had homozygous familial hypercholesterolemia; type I, III, IV, V, or secondary hyperlipoproteinemia; diabetes; or evidence of liver or renal impairment were excluded. At weeks 0, 2, 4, 8, 12, 16, 20, and 24 of the active-treatment period, levels of LDL-C, high-density lipoprotein cholesterol (HDL-C), TG, and total cholesterol (TC) were measured. RESULTS: Of the 1183 patients enrolled, 695 were randomly assigned to treatment--346 to fluvastatin ER 80 mg QPM, 174 to fluvastatin IR 40 mg QPM, and 175 to fluvastatin IR 40 mg BID. Patients were well matched between groups, with a mean age of approximately 56 years and body mass index of 27 kg/m2; 56.0% of patients (389/695) were female and 97.7% (679/695) were white. Fluvastatin ER 80 mg QPM lowered LDL-C levels significantly more than did fluvastatin IR 40 mg QPM (33.7% vs 24.4%; P < 0.001) and as effectively as fluvastatin IR 40 mg BID (33.9%). More than half of the patients administered fluvastatin ER 80 mg QPM and IR 40 mg BID achieved reductions in LDL-C levels of > or = 35%; more than half of those administered fluvastatin IR 40 mg QPM experienced reductions in LDL-C levels of > or = 25%. The mean reductions in LDL:HDL ratio, TC, and apolipoprotein B levels in the fluvastatin ER 80 mg QPM group were significantly greater than the reductions in the IR 40 mg QPM group (P < 0.001). In patients with mixed dyslipidemia, fluvastatin ER 80 mg reduced triglycerides by 21.8% (median 28%) and increased HDL-C by 14.5%. Fluvastatin ER 80 mg QPM was well tolerated, with incidences of clinically notable elevations in alanine aminotransferase, aspartate aminotransferase, and creatine kinase levels and musculoskeletal adverse events comparable to those in the IR 40 mg QPM group. CONCLUSION: The ER 80-mg formulation of fluvastatin is effective and well tolerated as a once-daily starting and maintenance treatment for primary hypercholesterolemia.
Asunto(s)
Anticolesterolemiantes/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Hipercolesterolemia/tratamiento farmacológico , Indoles/administración & dosificación , Adulto , Anciano , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Ácidos Grasos Monoinsaturados/efectos adversos , Femenino , Fluvastatina , Humanos , Indoles/efectos adversos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Persisting chylomicron remnant concentrations have been linked to premature atherosclerosis. The analysis of persisting chylomicron remnant concentrations by an oral triglyceride tolerance test, however, is time-consuming for the study subjects and requires large resources in the laboratory. Therefore, only small numbers of subjects have been studied in the past. We describe major improvements of the testing procedure in regard of composition of the fatty meal, of patient testing, and measurement of postprandial remnants. Shifting the time of the (ready-to-use) fatty drink from the morning hours to bedtime was well accepted by the study subjects and allowed the analysis of blood samples drawn at the morning with minimal impact on the participants' time and with minimal interferences by confounding factors (e.g. smoking, additional food intake, physical activity). Chylomicron remnants were measured by fluorometry of the supernatant after ultracentrifugation. This procedure was sensitive, was specific for chylomicron remnants, and was easy to perform. The biological validity of the improved procedure was evaluated by studying type III hyperlipoproteinemia patients and normolipemic apolipoprotein (Apo) E2 homozygotes. In conclusion, this improved test permits the rapid testing for persisting chylomicron remnants in the clinical routine and in large epidemiological studies.
Asunto(s)
Apolipoproteínas E/análisis , Quilomicrones/análisis , Grasas de la Dieta/sangre , Hiperlipoproteinemia Tipo III/sangre , Lipoproteínas/sangre , Adulto , Anciano , Apolipoproteína E2 , Apolipoproteína E3 , Cromatografía en Gel , Remanentes de Quilomicrones , Electroforesis en Gel de Poliacrilamida , Femenino , Homocigoto , Humanos , Immunoblotting , Masculino , Persona de Mediana Edad , Fenotipo , Periodo Posprandial/fisiología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Fluorescencia , Encuestas y Cuestionarios , UltracentrifugaciónRESUMEN
Although influences of cholesterol-rich lipoproteins on platelet aggregation are well established, the knowledge of interactions between triglyceride-rich lipoproteins and platelets, in particular in the postprandial state, is limited and controversial. The in-vitro effects of these lipoproteins from hypertriglyceridemic subjects on the aggregation behavior of platelets from normolipemic donors were investigated with two whole-blood methods. VLDL and chylomicrons, but not chylomicron remnants, in concentrations comparable to concentrations occurring after a fatty meal, reduced platelet aggregation in a dose-dependent manner in particle counting. Impedance aggregometry failed to monitor these effects. We conclude, that triglyceride-rich lipoproteins inhibit platelet aggregation in vitro. They may, therefore, not be linked to the acute onset of myocardial infarction.
Asunto(s)
Quilomicrones/fisiología , Lipoproteínas VLDL/fisiología , Agregación Plaquetaria/fisiología , Adulto , Humanos , Hiperlipoproteinemia Tipo II/metabolismo , Lipoproteínas VLDL/química , Lipoproteínas VLDL/aislamiento & purificación , Persona de Mediana Edad , Triglicéridos/sangreRESUMEN
The aims of this double-blind study were to examine whether in hypertriglyceridemic men the ingestion of a standardized fatty meal alters hemostasis negatively and whether triglyceride-lowering treatment with etofibrate for 6 weeks alters fasting and postprandial hemostasis positively, thus reversing the potential negative effects of a fatty meal on postprandial hemostasis. To answer these questions, we measured markers of hemostasis immediately before a standardized fatty meal, and 4, 6, 8, and 10 hours after the meal in 21 hypertriglyceridemic men both before and after treatment with etofibrate. We found that the concentration of plasmin alpha2antiplasmin complex markedly increased for at least 10 hours after the fatty meal, but that the activation of factor XII and the concentration of prothrombin activation fragment1+2 decreased after the fatty meal. These results on factor XII contradict reported in vitro data. Triglyceride-lowering treatment with etofibrate in 10 of these men for 6 weeks increased fasting and postprandial protein C and plasminogen and also slightly decreased the activation of fXII; however, it did not reverse the postprandial increase of PAP or change the decrease of prothrombin activation fragment1+2. Our findings indicate that postprandial lipoproteins alter markers of hemostasis positively in an antithrombotic and profibrinolytic direction. In addition, triglyceride-lowering treatment with etofibrate only slightly improves markers of fasting and postprandial hemostasis in an antithrombotic and profibrinolytic direction.