Laboratory Evaluation of Antiphospholipid Antibodies in Patients With Venous Thromboembolism

The objective of our study was to evaluate the significance of extended antiphospholipid profile in patients with venous thromboembolism without any systemic autoimmune disease. In 140 patients (age 18-69 years; 47.1% men) with venous thromboembolism and 136 control participants we tested anticardiolipin antibodies, anti-beta 2 glycoprotein I (anti-β2-GPI) and also non-criteria antiphospholipid antibodies: antiphosphatidic acid, antiphosphatidylethanolamine, antiphosphatidylglycerol, antiphosphatidylinositol, antiphosphatidylserine. Commercial and in-house enzyme-linked immunosorbent assays were used. The antibodies with significantly higher prevalence in patients (compared to controls) were: immunoglobulin (Ig) M-anticardiolipin antibodies (12.9%; P = 0.035), IgG-anti-β2-GPI (16.4%; P = 0.0032), IgM-antiphosphatidylethanolamine (14.3%; P = 0.014). In most cases, these three antibodies did not overlap. In conclusion, of non-criteria antiphospholipid antibodies, only antiphosphatidylethanolamine were significantly more prevalent in patients with venous thromboembolism, with only minor overlapping with the criteria antiphospholipid antibodies. Our results suggest the possible utility of searching for antiphosphatidylethanolamine in the clinical suspicion of antiphospholipid syndrome and the absence of criteria antiphospholipid antibodies.

Asymmetric dimethylarginine and the effect of folate substitution in children with familial hypercholesterolemia and diabetes mellitus type 1

A recently discussed cardiovascular risk factor, asymmetric dimethylarginine (ADMA), is known to act as an endogenous inhibitor of endothelial nitric oxide synthase. The aim of this study was to establish 1) the relationship between ADMA and ultrasonographically or biochemically determined endothelial dysfunction in children, and 2) the effect of folate supplementation on these parameters. The study cohort included 32 children with familial hypercholesterolemia (FH), 30 with diabetes mellitus type 1 (DM1) and 30 age-matched healthy children as the control group. Furthermore, twenty-eight randomly selected FH and DM1 children were re-examined after 3-months supplementation with folic acid. Baseline levels of ADMA and oxidized low density lipoproteins (oxLDL) were significantly higher in FH group than in DM1 and healthy children. Children in DM1 group had significantly lower concentration of homocysteine, but ADMA levels were normal. Folic acid supplementation significantly lowered homocysteine and hsCRP levels in both FH and DM1 group; however, ADMA and oxLDL concentrations remained unaltered. In conclusion, ADMA and oxLDL appear to be associated with endothelial dysfunction in children with FH. Administration of folic acid did not influence these markers in both FH and DM1 children.

Synergistic effect of angiotensin II type 1 receptor and endothelial nitric oxide synthase gene polymorphisms on arterial stiffness

Angiotensin II and nitric oxide belong to important factors in the functional and structural changes of vessel wall, leading to its increased stiffness. We investigated, whether common mutations of angiotensin II type 1 receptor (AGTR(1)) and endothelial nitric oxide synthase (eNOS) are associated with increased arterial stiffness. Two polymorphisms, A(1166)C of AGTR(1) and T(786)C of Enos, were estimated in a random, general population-based sample of 250 subjects. Arterial stiffness was measured using Sphygmocor as aortic (carotid-femoral) and peripheral (femoral-tibial) pulse wave velocities (PWV). Carriers of 3-4 mutant alleles from both polymorphisms, that is, homozygous for both mutations or homozygous for one and heterozygous for the second one, showed significantly higher peripheral PWV (17.92+/-2.40) than those with none or only 1-2 mutant alleles (12.37+/-0.51; P<0.003). Carriers of 3-4 mutant alleles had three times higher risk of having increased peripheral PWV (>or= 13.63 m s(-1), that is, in the top quartile) and this association remained significant after adjustment for potential confounders. No association was found between estimated genotypes and aortic PWV. In conclusion, combination of A(1166)C of AGTR(1) and T(786)C of eNOS mutations increased stiffness of muscular-type arteries.

Even mild changes in free thyroxine could influence the degree of heart failure measured by its biological surrogates

Both, severe hypo- or hyperthyroidism may alter hemodynamic parameters. The aim of our study was to ascertain, whether also distinct changes within normal range of free thyroxine (fT4) would be associated with an impairment of left ventricle function in patients with chronic heart failure. Hundred-forty-eight patients (m121, f27, mean age 63.8 +/- 1.14 years) with chronic heart failure, fT4 levels within the normal range (9-22 pmol/l) and without thyrostatics or substitution treatment. Degree of heart failure was quantified by plasma B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP). Patients with fT4 in the range 11.9-14.6 pmol/l [optimal, second-third quintile] had significantly lower NT-proBNP (718 +/- 70.4 pg/ml), than those with fT4 < or = 11.8 [low-normal, bottom quintile](1236 +/- 223.6 pg/ml; p<0.03) and those with fT4 over 14.6 pmol/l [high-normal, top two quintiles] (1192 +/- 114.9 pg/ml; p<0.0002). These differences remain significant, also if adjusted for age, gender and other confounders; adjusted odds ratio was 1.30 (1.05-1.59) for optimal vs. low-normal and 1.27 (1.04-1.55) for optimal vs. high-normal. Similar statistical differences were also found in BNP, but only when optimal and high-normal fT4 ranges were compared. In conclusion, the severity of heart failure seems to be also influenced by only mild deviations of fT4 concentrations from optimal levels.

Mild hyperhomocysteinaemia is associated with increased aortic stiffness in general population

Total homocysteine (tHcy) level was identified as a strong and independent predictor of cardiovascular events. We investigated the association between tHcy and mechanical properties of large arteries in a random, general population-based sample of 251 subjects (mean age 48 years). Large artery properties, such as aortic and peripheral (lower-limb) pulse wave velocity (PWV), and augmentation index of radial artery were measured using semi-automatic Sphygmocor device. Aortic PWV (APWV) positively correlated with tHcy (r = 0.28, P<0.0001), and a significant increasing trend of APWV was found by tHcy quartiles (P = 0.0003 by ANOVA). This association remained significant after adjustment for conventional cardiovascular risk factors (age, gender, smoking, overweight, hypertension, dyslipidaemia and impaired glucose metabolism) and for usual homocysteine confounders (folate, B12, renal function). Subjects with mild hyperhomocysteinaemia (i.e. with tHcy > or = 15 micromol/l) had 2.74 times higher risk of having their APWV over 8.42 m/s (i.e. in the top quartile). No such association was found either for PWV measured at lower extremity or for radial augmentation index. In conclusion, in our series of subjects from general population, we found a strong and independent relationship between homocysteine concentration and APWV, a parameter of stiffness of central arteries.

Folate co-administration improves the effectiveness of fenofibrate to decrease the lipoprotein oxidation and endothelial dysfunction surrogates

Fibrate therapy results in elevation of plasma total homocysteine (tHcy), which is known to induce oxidative stress and endothelial dysfunction. We aimed to establish whether fibrate-induced elevation of tHcy has also similar consequences and whether they may be prevented by folate co-administration. Eighteen subjects with hypercholesterolemia were included in an open, prospective, cross-over study. We compared intra-individually the effect of fenofibrate on tHcy, oxidative stress and endothelial dysfunction surrogates, in monotherapy and when combined with 10 mg of folate. These effects were also compared with fluvastatin monotherapy. Fenofibrate in monotherapy significantly decreased LDL cholesterol, increased the tHcy by 39.5 %, while oxidized LDL (oxLDL), malondialdehyde (MDA), von Willebrand factors (vWf) and thrombomodulin (TMD) remained unchanged. When fibrate was co-administered with folate, the tHcy remained on the initial post-diet level, while both the total and oxLDL as well as MDA, vWf and TMD decreased. In contrast to fenofibrate monotherapy, fluvastatin (80 mg) had a similar effect as combined therapy with fenofibrate and folate, while tHcy remained uninfluenced. In conclusion, fenofibrate decreases the LDL cholesterol, but in contrast to fluvastatin, has no significant antioxidative and endothelium-protective potential, probably due to a concomitant increase of tHcy. These effects may be improved by co-administration of folate.

Assays for the RNA chaperone activity of proteins

Proteins with RNA chaperone activity promote RNA folding by loosening the structure of misfolded RNAs or by preventing their formation. How these proteins achieve this activity is still unknown, the mechanism is not understood and it is unclear whether this activity is always based on the same mechanism or whether different RNA chaperones use different mechanisms. To address this question, we compare and discuss in this paper a set of assays that have been used to measure RNA chaperone activity. In some assays, this activity is related to the acceleration of monomolecular reactions such as group I intron cis-splicing or anti-termination of transcription. Hereby, it is proposed that the proteins release the RNAs from folding traps, which represent the kinetic barriers during the folding process and involve the loosening of structural elements. In most assays, however, bimolecular reactions are monitored, which include the simple acceleration of annealing of two complementary RNAs, the turnover stimulation of ribozyme cleavage and group I intron trans-splicing. The acceleration of these reactions most probably involves the unfolding of structures that interfere with annealing or folding and may in addition provoke annealing by crowding. Most assays are performed in vitro, where conditions might differ substantially from intracellular conditions, and two assays have been reported that detect RNA chaperone activity in vivo.

[Recommendations for the treatment of tobacco dependence]

This first Czech version of guidelines formulated by the working group of mentioned medical associations is based on current literature and international guidelines. They are aimed mainly on clinical medicine and on incorporation of this treatment into the health care system according to WHO recommendations. They should serve to the treatment of tobacco dependence at any level: during any contact with the smoking patient (short intervention), in specialised centres or for the health care providers or health system itself.

[Epidemiological study of hypothyroidism as cardiovascular risk in population]

BACKGROUND

Prevalence of hypothyroidism (HT) markedly differs among various populations. We aimed to establish the prevalence of HT in the Czech population and to assess its association with conventional cardiovascular risk factors.

METHODS AND RESULTS

1240 subjects (629 m, 611 f; mean age 52.3); a random, population-based sample were evaluated. Cut-off points for thyroid parameters were defined as follows: thyreostimulating hormone (TSH) 0.58-3.65 mU/I, free thyroxine (fT4) 9-22 pmol/l and thyroid peroxidase antibodies (TPOAb) < or = 14 IU/A. The overall prevalence of HT was 6.8% in males and 13.8% in females (p < 0.0001); subclinical HT (high TSH, normal fT4) was found in 3.0% and 8.0%, overt-untreated (high TSH, low fT4) in 3.2% and 3.0% and overt-treated HT in 0.6% and 2.8% of males and females, respectively. Moreover, in euthyroid subjects, 4.6% of males and 9.3% of females showed positive TPO-Ab (p < 0.0001). The adjusted relative risk of hypothyroidism was significantly increased in males with manifest vascular disease (odds ratio 3.48 (1.56-7.74)]), in females aged > or = 55 years (2.08 (1.29-3.36)) or hypertension (1.80 (1.03-3.13)), and moreover, in males and females with positive TPOAb (5.81 (2.57-13.13) and 5.92 (3.38-10.36), resp.)

CONCLUSIONS

Hypothyroidism was found in Czech population highly prevalent and it can contribute to the coronary risk, produced by conventional factors.

[Association between free thyroxin concentration and degree of heart failure in patients with chronic heart insufficiency]

BACKGROUND

It is evident, that overt thyroid dysfunction (both, hypo- or hyperthyroidism) could be associated with heart failure. The aim of our study was to establish whether also mild changes in free thyroxin (fT4) may influence the degree of heart failure in patients with chronic heart insufficiency.

METHODS AND RESULTS

There were included 148 patients (m 121, f 27, mean age 63.8 +/- 1.14) with clinical chronic heart failure were, with fT4 levels within the normal range (9-22 pmol/l) and without thyroid suppression or substitution treatment. Degree of heart failure was quantified by plasma B-type natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP) and big endothelin. Patients with fT4 in the range 11.9-14.6 pmol/l (optimal, 3rd-6th decile) had significantly lower NT-proBNP (718 +/- 70.4 pg/ml), than those with fT4 < or = 11.8 (low-normal, bottom two deciles) (1236 +/- 223.6 pg/ml; p < 0.03) and those with fT4 over 14.6 pmol/l [high-normal, top four deciles] (1192 +/- 114.9 pg/ml; p < 0.0002). These differences remain significant also if adjusted for age, gender and other confounders; adjusted odds ratio was 1.30 (1.05-1.59) for optimal vs. low-normal and 1.27 (1.04-1.55) for optimal vs. high-normal. Similar statistical differences were found also in BNP and high endothelin, but only between optimal and high-normal fT4 strata.

CONCLUSIONS

The degree of heart failure could be influenced also by mild changes in fT4 concentration.

[Pilot study of the noninvasive assessment of endothelial dysfunction by post-occlusion dopplerometry velocity curves analysis in arteria brachialis]

BACKGROUND

A new method of noninvasive assessment of endothelial dysfunction was used in this pilot study. Study has been set on a. brachialis dopplerometry velocity curves analysis. Index of blood stream deceleration between the first and second minute of the postocclusion periode was measured on a. brachialis after transient mechanical occlusion of the forearm--so called Deceleration Index.

METHODS AND RESULTS

Eighteen patients with so far untreated hypercholesterolemia were involved in our study. Profile of velocity curves became significantly different after six months of fluvastatin therapy, Deceleration Index increased from 3 % to more than 7 % (p<0.05). That correlated with LDL-CH levels decrease, but also with the significant decrease of biochemical markers of endothelial dysfunction (trombomodulin, von Willebrand factor).

CONCLUSIONS

The result is corresponding with previously published studies that have proved endothelial function improvement after statin therapy using another ultrasonographic methods.

[Quality of therapeutic control of hyperlipidemias in secondary prevention of coronary heart disease in the light of current recommendations]

Definite evidence has been established, that coronary patients benefit from appropriate therapeutic control of risk profile, as recommended by several Guidelines. However, the impact of these Guidelines on coronary morbidity and mortality is limited by level of its implementation into broad clinical practice and possibility to reach the defined secondary preventive targets with currently available therapeutic resources. We reviewed 6 studies, realized between 1995 and 2000, which was aimed to establish, how many patients with clinical coronary heart disease achieved recommended targets for lipid-lowering treatment. From 10850 cardiac patients examined in these surveys, in average 42.8% were treated with lipid lowering drugs, but only in 26.8% and 24.3% of patients was reached the target level for total and LDL cholesterol, resp. On the other hand use of lipid lowering drugs markedly increased from about 16-32% in 1995, 61-93% in 2000, moreover in the same time period the proportion of patients reaching target levels of total cholesterol increased from about 14-18% to 30-64%.

Connaissance et prévention des borrélioses par piqûres de tiques

INTRODUCTION

European borreliosis, known to the general public as 'Lyme disease' in analogy with the American form, which it differs from in many points, is endemic in the area of Alsace and is a public health problem. The level of knowledge and prevention of the population with regard to the disease has never been assessed in France.

MATERIAL AND METHODS

A survey was conducted in all the national health examination centers in Alsace using a self-applied questionnaire. The data collected concerned the socio-demographical characteristics, knowledge on the disease, history of tick bites, fear the disease creates, frequency of visits to the forest, prevention habits when visiting the forest and the attitude adopted in the case of a tick bite.

RESULTS

Out of the 600 persons included, 99 (16.5 p.cent) had been bitten by ticks once or more over the past year. The existence of Lyme's disease was known to 74 p.cent of the consultants, 63 p.cent claimed they were worried by the disease and 43 p.cent knew that the first manifestation is redness spreading over the skin. Twenty-seven percent wore trousers and long sleeves when visiting the forest and 19 p.cent inspected their body carefully on their return. The persons least well informed were also those who did little to protect themselves against tick bites. They often were under 30 years old, lived in urban settings and had few diplomas. Those who had frequent spare time in forest and those who had a history of tick bites were the best informed and protected themselves better. The fear of the disease was associated with better knowledge and more appropriate behaviour.

DISCUSSION

This study shows that a large percent of the population in Alsace is exposed to tick bites. Tick bite borreliosis is relatively well known, but protection remains insufficient. Better knowledge of the disease is related to better prevention. Information and teaching campaigns for the general public could specifically target the young people, urban dwellers and those with few diplomas. Specific messages of prevention could be delivered to the most exposed at-risk subjects (i.e. those bitten by ticks or having leisure in forest) at the places of their leisure or medical consultations.