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Total Homocysteine (total + homocysteine)
Kinds of Total Homocysteine Terms modified by Total Homocysteine Selected AbstractsPolymorphisms in genes related to folate and cobalamin metabolism and the associations with complex birth defectsPRENATAL DIAGNOSIS, Issue 6 2008R. Brouns Abstract Objective To investigate the associations between biomarkers and genetic variants involved in homocysteine metabolism and the risk of complex birth defects. Methods Total homocysteine (tHcy), folate, cobalamin, apo-transcobalamin (apo-TC) and apo-haptocorrin (apo-HC) were measured in the amniotic fluid of 82 women who were pregnant with a child having a complex birth defect, such as neural tube defect, cleft lip and/or palate, heart defect or omphalocele, and in 110 women pregnant with a non-malformed child. The determined genotypes of the child comprised of 5, 10-methylenetetrahydrofolate reductase (MTHFR 677C > T, 1298A > C), methionine synthase (MTR 2756A > G), methionine synthase reductase (MTRR 66A > G) and transcobalamin (TCN2 776C > G). Univariate and multivariate logistic regression analyses were performed. Results Significantly lower cobalamin and higher apo-TC, apo-HC, tHcy and folate concentrations were determined in amniotic fluids of cases compared with controls (p,0.001). Logistic regression analysis revealed that after adjustment for maternal age, children carrying the MTHFR 677T allele showed a four-fold increased risk of having a complex birth defect, OR (95% CI) = 4.0 (1.1,15.4). Other genotypes did not show significant associations. Conclusion The MTHFR 677C > T polymorphism in conjunction with reduced folate- and/or cobalamin status may increase the risk of complex birth defects. Copyright © 2008 John Wiley & Sons, Ltd. [source] Reduced plasma total homocysteine concentrations in Type 1 diabetes mellitus is determined by increased renal clearanceDIABETIC MEDICINE, Issue 3 2005B. A. J. Veldman Abstract Introduction Elevated plasma levels of total homocysteine are related to the development of vascular complications. Patients with diabetes mellitus are particularly at risk for the development of these complications. Several factors determine plasma total homocysteine including renal function. Aims As early Type 1 diabetes is characterized by a relative glomerular hyperfiltration, increased renal clearance could contribute to decreased levels of homocysteine as observed in Type 1 diabetes mellitus. Therefore we investigated the relationship between plasma total homocysteine and the glomerular filtration rate (GFR). Methods In 92 Type 1 diabetes patients and 44 control subjects, we measured GFR and effective renal plasma flow (ERPF) by means of continuous infusion of inulin and p-aminohippurate. Fasting plasma total homocysteine was measured using high performance liquid chromatography. Results GFR (121 ± 21 resp. 104 ± 14 ml/min; P < 0.001) and ERPF (563 ± 127 resp. 516 ± 121 ml/min; P = 0.05) were significantly higher in Type 1 diabetes patients as compared with control subjects. Plasma total homocysteine was reduced in Type 1 diabetes patients as compared with control subjects (11.0 ± 4.5 resp. 13.4 ± 7 µmol/l; P = 0.01). Plasma total homocysteine was strongly correlated with GFR (Type 1 diabetes patients: r = ,0.43, P < 0.001; control subjects: r = ,0.39, P = 0.01). Conclusion GFR is a major determinant of plasma total homocysteine levels in Type 1 diabetes patients as well as control subjects. The reduced plasma total homocysteine levels in diabetes patients can be explained by an increased GFR. [source] Hyperhomocysteinemia in Children Treated with Antiepileptic Drugs Is Normalized by Folic Acid SupplementationEPILEPSIA, Issue 10 2005Martina Huemer Summary:,Purpose: To assess the prevalence of hyperhomocysteinemia in pediatric patients treated with antiepileptic drugs (AEDs) and to evaluate the effect of folic acid supplementation on plasma total homocysteine (tHcy) concentrations in hyperhomocysteinemic patients. Methods: 123 patients from three regional hospitals participated in the study. Patients with hyperhomocysteinemia were included in a 3-month double-blind randomized trial testing oral folic acid supplementation (1 mg/day) versus placebo. Results: Hyperhomocysteinemia (tHcy >10.4 ,mol/L) was present in 19 of 123 patients. Patients with hyperhomocysteinemia were older (13.7 ± 4 vs. 11.0 ± 3.9 years) and had significantly lower folate and cobalamin concentrations. Multidrug (two or more) AED treatment and duration of therapy correlated significantly with elevated total homocysteine (tHcy) and low folate. In contrast, polymorphisms in the methylene tetrahydrofolate reductase gene (MTHFR 677 C,T, 1298 A,C, 1793 G,A) had no significant impact on tHcy. Nine of 19 patients with hyperhomocysteinemia were randomized to placebo, whereas the remaining 10 patients received folic acid supplementation. Folic acid supplementation resulted in a significant increase of folate and decrease of tHcy, whereas both parameters remained unchanged in the placebo group. Conclusions: Hyperhomocysteinemia is present in 15.5% of children receiving long-term AED treatment. Multidrug treatment and long duration of therapy enhance the risk for hyperhomocysteinemia. Folic acid supplementation significantly reduces tHcy. We recommend assessment of serum folate and plasma tHcy in children receiving AEDs. [source] Serum homocysteine, creatinine, and glucose as predictors of the severity and extent of coronary artery disease in asymptomatic members of high-risk familiesEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2002P. Pajunen Abstract Background There has been no previous study to determine the severity and extent of coronary artery disease (CAD) in subjects with no diagnosis or symptoms of CAD at the time of the angiography. Methods Fifty-three subjects, who were siblings of patients with early onset CAD, underwent coronary angiography. Indices to describe per-patient characteristics of CAD were calculated, based on computer-aided quantitative coronary angiography. Clinical and laboratory characteristics were correlated to the angiographic parameters. Results Serum total homocysteine (, = 0·29, P < 0·05) and creatinine (, = 0·47, P = 0·001) levels were related to the global atheroma burden index. The median of the atheroma burden index was two times higher in the top homocysteine quartile compared to the lowest quartile. The overall atheroma burden index correlated significantly with the fasting blood glucose level in all subjects. Diabetes, especially when albuminuria was present, was a powerful risk factor. In a multivariate analysis, only age and sex were independent predictors of atheroma burden. Conclusions Serum homocysteine and creatinine concentrations, and diabetes with albuminuria were found to be markers of the severity and extent of CAD in subjects of high-risk families without symptoms of CAD. [source] Response to Dr Spence: Plasma total homocysteine in acute strokeEUROPEAN JOURNAL OF NEUROLOGY, Issue 8 2007T. Tatlisumak No abstract is available for this article. [source] Plasma total homocysteine in acute strokeEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2007J. D. Spence No abstract is available for this article. [source] Plasma total homocysteine levels are associated with advanced leukoaraiosis but not with asymptomatic microbleeds on T2*-weighted MRI in patients with strokeEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2006H. Naka Both leukoaraiosis and asymptomatic microbleeds are associated with small-artery diseases. Although an association between hyperhomocysteinemia and leukoaraiosis has been reported, no studies have evaluated the association between total homocysteine (tHcy) level and presence of microbleeds in stroke patients. We evaluated the association between tHcy level and leukoaraiosis or microbleeds in stroke patients. In 102 patients with stroke (69.5 ± 10.3 years old, 54 men and 48 women), microbleeds on T2*-weighted MR images were counted, leukoaraiosis on T2-weighted images was graded and fasting plasma tHcy concentrations were measured. Plasma tHcy level was significantly higher in patients with advanced leukoaraiosis than in those without advanced leukoaraiosis (13.9 ± 4.6 ,mol/l vs. 10.2 ± 3.4 ,mol/l, P < 0.0001). Plasma tHcy level was not significantly different in patients with microbleeds and those without microbleeds (11.3 ± 4.1 ,mol/l vs. 11.4 ± 4.3 ,mol/l, P = 0.9441). Elevated tHcy level is significantly and independently associated with advanced leukoaraiosis [odds ratio (OR), 1.330; 95% CI, 1.130,1.565] but not with the presence of microbleeds. Elevated tHcy level appears to be associated with ischemic small-artery disease rather than with bleeding-prone small-artery disease. [source] Uremic hyperhomocysteinemia: A randomized trial of folate treatment for the prevention of cardiovascular eventsHEMODIALYSIS INTERNATIONAL, Issue 2 2007Areuza C. A. VIANNA Abstract Homocysteine is a risk factor for atherosclerosis in the general population, and serum homocysteine levels are almost universally elevated in chronic renal failure patients. When such patients are treated with dialysis, cardiovascular disease accounts for more than 50% of their mortality, which, in some proportion, may be pathophysiologically related to the elevated serum homocysteine levels. From April 2003 to March 2005, we conducted a 2-year, double-blind, randomized, placebo-controlled trial of 186 patients with end-stage kidney disease due to any cause, who were older than 18 years and stable on hemodialysis. Patients were assigned to receive either oral folic acid 10 mg 3 times a week immediately after every dialysis session under nurse supervision or an identical-appearing placebo for the entire study. On admission, plasma total homocysteine (tHcy) levels were above 13.9 ,mol/L in 96.7% of patients (median 25.0 ,mol/L, range 9.3,104.0 ,mol/L). In the placebo group, tHcy levels remained elevated at 6, 12, and 24 months, while oral folate significantly decreased tHcy to a median value of 10.5 (2.8,20.3) ,mol/L, (p<0.01). During the study, 38 patients (folic acid group 17 vs. placebo group 21; p=0.47) died from cardiovascular disease. Kaplan,Meier life table analysis dealing with the incidence of cardiovascular events, both fatal and nonfatal (myocardial infarction, arrhythmias, angina, heart failure, cerebrovascular accident), showed that 2 years of folic acid treatment and the lowering of the homocysteine blood levels had no effect on cardiovascular events (p=0.41; hazard ratio 1.24, 95% CI 0.74,2.10). However, the carotid artery intima-media wall thickness measured in a blinded fashion decreased from 1.94 ± 0.59 mm to 1.67 ± 0.38 mm (p<0.01) after 2 years of folate therapy. In this short-term study of uremic patients, 2 years of folic acid supplementation normalized the tHcy blood levels in 92.3% of patients but did not change the incidence of cardiovascular events compared with the control group. However, ultrasonography of the common carotid arteries performed at entry and 24 months later showed a significant decrease in intima-media thickness with folate supplementation. This suggests that early folate supplementation may benefit patients with chronic renal failure by preventing cardiovascular deterioration. [source] A population-based intervention study on elevated serum levels of methylmalonic acid and total homocysteine in elderly people: results after 36 months of follow-upJOURNAL OF INTERNAL MEDICINE, Issue 5 2004K. Björkegren Abstract. Objectives., To study the effects of vitamin B12 and folic acid treatment on haematological measures, reported symptoms and clinical findings over a 3-year period. Design., A longitudinal two-cohort study. Setting., A mid-Swedish community. Subjects., A 20% random sample of persons 70 years or older in a defined geographical area were invited to a survey (n = 266). Sixty-nine persons who had serum cobalamin <300 pmol L,1 and serum methylmalonic acid (MMA) ,0.37 ,mol L,1 or serum total homocysteine (tHcy) ,15 ,mol L,1 and who had no vitamin B12 or folic acid substitution were selected for treatment. Main outcome measures., Serum cobalamin, folate, MMA and tHcy. Presence of gastrointestinal, neurological, psychiatric and some other symptoms, obtained by questionnaire, and Mini Mental State Examination (MMSE) score, vibration sense measurement and findings at a physical examination. Results., After combined vitamin B12,folic acid treatment, all persons normalized their serum tHcy and MMA levels and the effect remained after 3 years. The study design allowed separation of pure vitamin B12 deficiencies from folate and combined deficiencies. There was a tendency towards improvement of vibration sense, especially in the long nerve paths, and improvement of neurological symptoms and oral mucosa findings. No improvement was seen for other symptoms, reflex activity or MMSE score. Conclusions., Vitamin treatment of elderly people in the early phase of the condition may reverse damage that otherwise would become irreversible. If initiated, the treatment should be combined with vitamin B12 and folic acid. [source] Homocysteine, malondialdehyde and endothelial markers in dialysis patients during low-dose folinic acid therapyJOURNAL OF INTERNAL MEDICINE, Issue 5 2002T. Apeland Abstract. Apeland T, Mansoor MA, Seljeflot I, Brønstad I, Gøransson L, Strandjord RE (Rogaland Central Hospital, Stavanger; and Ullevål University Hospital, Oslo; Norway). Homocysteine, malondialdehyde and endothelial markers in dialysis patients during low-dose folinic acid therapy. J Intern Med 2002; 252: 456,464. Objectives. Haemodialysis patients have elevated levels of the atherogenic amino acid homocysteine. We wanted to assess the effects of small doses of intravenous folinic acid (the active form of folic acid) on some biochemical risk factors of cardiovascular disease. Design. Longitudinal and open intervention study. Setting. Two dialysis units in the County of Rogaland. Subjects. All patients on maintenance haemodialysis were invited, and 32 of 35 patients gave their informed consent. Interventions. After each dialysis session, the patients were given 1.0 mg of folinic acid intravenously thrice a week for a period of 3 months. Prior to and during the study, all patients were on maintenance supplementation with small doses of vitamins B1, B2, B3, B5, B6 and B12. Main outcome measures. Changes in the levels of (i) plasma total homocysteine (p-tHcy) and folate, (ii) circulating endothelium related proteins , markers of endothelial activation and (iii) serum malondialdehyde (S-MDA) , a marker of oxidative stress and lipid peroxidation. Results. The p-tHcy levels were reduced by 37% (P < 0.0001), whilst the serum and erythrocyte folate levels increased by 95 and 104%, respectively (P < 0.0001 for both). The circulating levels of endothelium related cellular adhesion molecules and haemostatic factors remained high and unchanged, except the thrombomodulin (TM) levels increased (P = 0.0004). The high levels of S-MDA were reduced by 26% (P = 0.003). Conclusions. Low doses of folinic acid given intravenously to dialysis patients reduced their levels of p-tHcy and S-MDA and thus improved their cardiovascular risk profile. The concurrent increment in TM levels was unexpected and of unknown clinical significance. [source] Hyperhomocysteinemia and low B vitamin levels are independently associated with venous thromboembolism: results from the EDITH study: a hospital-based case,control studyJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2006E. OGER Summary.,Background:,Moderate hyperhomocysteinemia and B vitamins deficiency are thought to be risk factors for venous thromboembolism (VTE). The causality and independence of those associations are still questioned. Methods:,We measured fasting serum total homocysteine, folates, and vitamin B12 levels as well as 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T genotypes in 467 patients hospitalized with a first well-documented deep vein thrombosis and/or pulmonary embolism not related to a major acquired risk factor and 467 controls matched for gender and age. Results:,Mild hyperhomocysteinemia, low serum folates, and vitamin B12 were associated with VTE independently of each other. In multivariate analysis, odds ratios (OR) (95% CI) for VTE associated with mild hyperhomocysteinemia (>15 ,mol L,1), low serum folates (,,4.9 nmol L,1), and vitamin B12 (, 253 pmol L,1) were 1.48 (1.05,2.08), 3.14 (1.35,7.32) and 1.42 (1.03,1.98), respectively. An MTHFRC677T genotype was not significantly associated with VTE; OR (95% CI): 1.13 (0.70,1.81) Conclusions:,The current data provides further knowledge in the complex relationship between hyperhomocysteinemia, low vitamin levels, and VTE. [source] Clinical trial: B vitamins improve health in patients with coeliac disease living on a gluten-free dietALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2009C. HALLERT Summary Background, Patients with coeliac disease living on a gluten-free diet show vitamin deficiency and reduced subjective health status. Aim, To study the biochemical and clinical effects of B vitamin supplementation in adults with longstanding coeliac disease. Methods, In a double blind placebo controlled multicentre trial, 65 coeliac patients (61% women) aged 45,64 years on a strict gluten-free diet for several years were randomized to a daily dose of 0.8 mg folic acid,0.5 mg cyanocobalamin and 3 mg pyridoxine or placebo for 6 months. The outcome measures were psychological general well-being (PGWB) and the plasma total homocysteine (tHcy) level, marker of B vitamin status. Results, Fifty-seven patients (88%) completed the trial. The tHcy level was baseline median 11.7 ,mol/L (7.4,23.0), significantly higher than in matched population controls [10.2 ,mol/L (6.7,22.6) (P < 0.01)]. Following vitamin supplementation, tHcy dropped a median of 34% (P < 0.001), accompanied by significant improvement in well-being (P < 0.01), notably Anxiety (P < 0.05) and Depressed Mood (P < 0.05) for patients with poor well-being. Conclusions, Adults with longstanding coeliac disease taking extra B vitamins for 6 months showed normalized tHcy and significant improvement in general well-being, suggesting that B vitamins should be considered in people advised to follow a gluten-free diet. [source] Effect of selenium status and supplementation with high-selenium yeast on plasma homocysteine and B vitamin concentrations in the UK elderlyMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 11 2008Bram Bekaert Abstract The level of plasma total homocysteine (tHcy), long known to be B vitamin dependent, has recently been shown to be inversely associated with plasma selenium (Se) concentration in human subjects. We therefore, chose to investigate the interaction between Se, tHcy and B vitamins in a double-blind, placebo-controlled trial where 501 healthy UK elderly volunteers were randomly allocated to receive 100, 200, or 300 ,g Se/day as high-Se-yeast, or placebo-yeast for 6 months. Plasma Se, tHcy, folate, vitamin B-12, pyridoxal-5,-phosphate (PLP) and its catabolite, 4-pyridoxic acid, were measured in all participants at baseline and in samples from the placebo, 100 and 300 ,g Se/day groups, at follow-up. At baseline, Se was inversely correlated with tHcy but only in males (p < 0.001). Before supplementation, tHcy concentration was significantly lower in the highest compared to the lowest Se tertile in males (p < 0.05), and in females when folate concentrations were also in the top tertile (p < 0.05). The effect of folate, PLP and vitamin B-12 concentrations on plasma tHcy correlated with Se concentration at baseline. After 6 months of Se supplementation, only Se concentration had changed significantly. Supplementation with Se does not affect tHcy concentration in the UK elderly population. [source] Determination of total homocysteine in dried blood spots using high performance liquid chromatography for homocystinuria newborn screeningPEDIATRICS INTERNATIONAL, Issue 1 2004Andi Dwi Bahagia Febriani AbstractBackground: The most widely used method for newborn screening for homocystinuria (HCU) is a semiquantitative bacterial inhibition assay for measuring methionine concentration in dried blood spots (DBS). Because this method has resulted in a number of missed cases due to many factors, we developed a high performance liquid chromatography (HPLC) method with fluorescence detection to measure total homocysteine (tHcy) in DBS which might be useful for newborn screening for HCU. Methods: One disk of DBS 3 mm in diameter was sonicated in 10 min. The extract was reduced with dithioerythritol and was derivatized with 4-aminosulfonyl-7fluoro-2,1,3-benzoxadiazole before injection into HPLC. Results: This method showed good linearity (r = 0.996), precision (coefficient of variation range 2.7,5%), and excellent correlation coefficient between DBS and serum tHcy, both in control (r = 0.932) and patient samples (r = 0.952). By this method, the mean tHcy concentration in DBS of preterm newborns, full-term newborns, and adults was 1.4 ± 1.0, 2.5 ± 1.6, and 4.9 ± 1.5 µmol/L, respectively. The mean tHcy DBS concentration in two cases of cystathionine-,-synthase deficiency and one case of 5,10-methylentetrahydrofolate reductase deficiency was 22.7 ± 2.88, 29.3 ± 1.90, and 41.3 µmol/L, respectively. Conclusions: The present method, which is rapid, user friendly and reliable, seems applicable to newborn screening of HCU in place of methionine measurement. [source] Metabolic effects and the methylenetetrahydrofolate reductase (MTHFR) polymorphism associated with neural tube defects in southern Brazil,BIRTH DEFECTS RESEARCH, Issue 7 2004Têmis Maria Félix Abstract BACKGROUND The importance of metabolic factors in neural tube defects (NTDs) has been the focus of many investigations. Several authors have suggested that abnormalities in homocysteine metabolism, such as hyperhomocysteinemia, folate deficiency, and low vitamin B12, may be responsible for these malformations and that both nutritional factors and genetic abnormalities are associated with them. METHODS We conducted a case-control study to investigate the influence of biochemical and genetic factors in NTDs in infants in southern Brazil. Levels of folate, vitamin B12, total homocysteine (t-Hcy) and the 677C>T and 1298A>C polymorphisms of the MTHFR gene were analyzed in 41 NTD child,mother pairs and 44 normal child,mother control pairs. RESULTS Subjects in the case group had a higher mean blood folate level than those in the control group. The level of vitamin B12 was lower in mothers in the NTD group than in control mothers (p = 0.004). The level of t-Hcy was not different in the two groups, but t-Hcy and vitamin B12 were correlated (p = 0.002). There was no difference in the genotype distribution for 677C>T and 1298A>C polymorphisms of MTHFR in the case and control pairs. The level of t-Hcy was correlated with 677TT. CONCLUSIONS Despite the small sample in this study, we suggest that low vitamin B12 and, consequently, hyperhomocysteinemia are important risk factors for NTDs in our population. Birth Defects Research (Part A), 2004. © 2004 Wiley-Liss, Inc. [source] Reduced in vivo oxidative stress following 5-methyltetrahydrofolate supplementation in patients with early-onset thrombosis and 677TT methylenetetrahydrofolate reductase genotypeBRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2005Antonio Coppola Summary The protective role of folate in vascular disease has been related to antioxidant effects. In 45 patients with previous early-onset (at age <50 years) thrombotic episodes and the 677TT methylenetetrahydrofolate reductase genotype, we evaluated the effects of a 28d-course (15 mg/d) of 5-methyltetrahydrofolate (MTHF) on homocysteine metabolism and on in vivo generation of 8-iso-prostaglandin F2, (8-iso-PGF2,), a reliable marker of oxidative stress. At baseline, patients' fasting total homocysteine (tHcy) was 11·5 ,mol/l (geometric mean) and urinary excretion of 8-iso-PGF2, was 304 pg/mg creatinine, with the highest metabolite levels in the lowest quartile of plasma folate distribution (P < 0·05). After 5-MTHF supplementation, plasma folate levels increased approximately 13-fold (P < 0·0001 versus baseline); tHcy levels (6·7 ,mol/l, P < 0·0001) and urinary 8-iso-PGF2, (254 pg/mg creatinine, P < 0·001) were both significantly lowered, their reduction being proportional to baseline values (r = 0·98 and r = 0·77, respectively) and maximal in patients with the lowest pre-supplementation folate levels (P < 0·05). The effects on folate (P < 0·0001) and tHcy (P = 0·0004) persisted for at least up to 2 months after withdrawing 5-MTHF. In parallel with long-lasting tHcy-lowering effects, a short-course 5-MTHF supplementation reduces in vivo formation of 8-iso-PGF2, in this population, supporting the antioxidant protective effects of folate in vascular disease. [source] The effects of thyroxine replacement on the levels of serum asymmetric dimethylarginine (ADMA) and other biochemical cardiovascular risk markers in patients with subclinical hypothyroidismCLINICAL ENDOCRINOLOGY, Issue 2 2005Omer Ozcan Summary Background, The relationship between subclinical hypothyroidism (SH) and cardiovascular disease (CVD) is still under debate. The purpose of the present study was to evaluate plasma total homocysteine (tHcy), high sensitive C-reactive protein (hsCRP), small dense low-density lipoprotein (sdLDL), l -arginine and asymmetric dimethylarginine (ADMA) concentrations and their relationship to nitric oxide (NO) production, measured as plasma nitrite-plus-nitrate (NOx) concentration, in patients with SH before and after thyroxine replacement therapy and compared with control group values. Design, Eighty-four women with SH and 33 healthy women as controls matched to the patient group for sex, age and body mass index (BMI), were enrolled in this study. Lipoprotein profile, tHcy, hsCRP, sdLDL, ADMA, l -arginine and NOx were measured in pre- and post-treatment blood samples. Results, The pretreatment total cholesterol (TC), LDL-C, hsCRP, ADMA and l -arginine levels were significantly higher and NOx levels were lower than in the control group. After treatment, hsCRP, ADMA and l -arginine levels were significantly reduced and sdLDL and NOx levels were significantly increased. Conclusion, The present study demonstrated an elevation of hsCRP and ADMA plasma levels of patients with SH associated with a reduction in NO production, which may contribute to some cardiovascular alterations. The elevated ADMA and hsCRP levels were reduced after thyroxine replacement. Also the sdLDL levels of SH patients were found to be lower than the control group values whereas TC and LDL were elevated. Even though we found an elevation in sdLDL levels after treatment, those values were still not higher than in the control group. [source] Single nucleotide polymorphism in CTH associated with variation in plasma homocysteine concentrationCLINICAL GENETICS, Issue 6 2004J Wang Plasma total homocysteine (tHcy) concentration, an independent risk factor of atherosclerosis, has numerous genetic and environmental determinants. While the thermolabile polymorphism in MTHFR encoding methylenetetrahydrofolate reductase is the best-studied genetic factor associated with variation in plasma tHCy, other candidate genes are being evaluated. Recently, we discovered that cystathioninuria was caused by mutations in the CTH gene encoding cystathionine ,-lyase, an enzyme that converts cystathionine to cysteine in the trans-sulfuration pathway. We also identified a common single nucleotide polymorphism (SNP), namely c.1364G>T (S403I) in exon 12 of CTH. In the current analysis, we studied the association of genotypes of this SNP with plasma tHcy concentrations in 496 Caucasian subjects. CTH 1364T/T homozygotes had significantly higher mean plasma tHcy concentration than subjects with other genotypes, and the effect sizes of CTH and MTHFR genotypes were similar. The findings suggest that common variation in CTH may be a determinant of plasma tHcy concentrations. [source] |