Contents of pentosidine in the tissue of the intervertebral disc as an indicator of the human age.

The study deals with the post-translational modifications of proteins - glycation of the tissue of the intervertebral disc and determination of one of advanced glycation end's products - pentosidine in the relation to the age. Pentosidine was detected in the hydrolysate of the intervertebral discs from persons between the ages of 16 and 95 years. 142 samples were analysed by high performance liquid chromatography, and the detected amounts of pentosidine were processed statistically. The coefficient of correlation of dependence of the amount of pentosidine on the age amounts to r = 0.92. The results of the work testify to the fact that it is possible to use the detection of pentosidine in the tissue of the intervertebral disc for the estimation of the age. Nevertheless subsequent experiments should be done under different conditions post-mortem decomposition.

International Staging System required standardization of biochemical laboratory testing in multiple myeloma.

The standardization of biochemical measurement procedures in multiple myeloma is necessary for reliable prognostic stratification of patients in multicentric trials. The new prognostic index International Staging System for multiple myeloma uses only two laboratory markers, albumin and beta-2 microglobulin. Our study compared results of albumin, beta-2 microglobulin and monoclonal immunoglobulin measurements from six centers which provide treatment for multiple myeloma in the Czech Republic and attempted to standardize the analytic procedures. We have found that the measurement of albumin is well standardized and the results from all laboratories were comparable. The measurement of beta-2 microglobulin achieved comparability only after a partial unification of analytical methods. The determination of monoclonal immunoglobulin concentration provided comparable results for concentrations higher than 20 g/l with higher variability for lower values.

[Prenatal diagnostics during the first trimester in the clinical praxis]. / Prenatální diagnostika v prvním trimestru gravidity v klinické praxi.

BACKGROUND: Biochemical screening test for Down's syndrome now offered in the 16th to 20th week of pregnancy reaches 60-65% sensitivity with 5% false positives. Newly introduced combined test done between 11+0 to 13+6 weeks of pregnancy, maternal serum biochemistry (free beta hCG a PAPP-A) and foetal nuchal translucency measurement, offer very early identification of Down's syndrome in foeti. The purpose of our study was the introduction of the new method and confirmation of the expected sensitivity and false positivity in our conditions. METHODS AND RESULTS: The combined test identified 5 of 6 (83%) of Down's syndrome foeti from the studied group of 2573 pregnancies. The false positive rate was 2.2%. Women aged 35 years or more represented 15% of our cohort. One Down's syndrome foetus with normal combined test was identified in the 21 week of pregnancy due to its heart failure which was diagnosed with ultrasound. Morover, 4 foeti with Edwards- and one with Turner syndrome were identified. CONCLUSIONS: In comparison with the second trimester biochemical screening, the first trimester combined test offers the information at the end of first trimester, it has higher sensitivity and low false positivity. The combined test gives clear outcomes, easy audit and control over ultrasound and biochemical results. Introduction of the first trimester screening requires strict adherence to the method both by the sonographer and the biochemical laboratory, and the acceptance of rigorous audit rules.

Impact of essential hypertension and primary aldosteronism on plasma brain natriuretic peptide concentration.

INTRODUCTION: Brain natriuretic peptide (BNP) has important role in the diagnosis and management of heart failure. Data on the impact of blood pressure (BP) on BNP are controversial. In primary aldosteronism (PA), BNP production can be affected by both hypertension and specific endocrine mechanisms. This study was aimed at investigating the impact of hypertension and hyperaldosteronism on plasma BNP levels. METHODS: Plasma BNP concentration, casual and 24-h BP and echocardiographic indices were assessed in 40 patients with moderate to severe essential hypertension (EH), 40 BP-matched patients with PA, and 40 age- and sex-matched healthy controls. RESULTS: BNP levels in PA and EH groups did not differ significantly and were higher compared with those in controls [median and interquartile range 26 (13-48) pg/ml, p = 0.01, and 23 (9-32) pg/ml, n.s., vs 14 (6-26) pg/ml in controls]. Remarkably elevated BNP was observed only in three PA and two EH patients, all having significant left ventricular (LV) hypertrophy. BNP levels in PA and EH groups correlated weakly with casual and 24-h BP, interventricular septal thickness and LV mass index (LVMI). Diastolic BP and LVMI were identified as the strongest independent determinants of BNP (p = 0.002 and p = 0.01, respectively). CONCLUSIONS: Both PA and EH patients had modest and mutually comparable elevation of BNP, which was independently determined by diastolic BP and LVMI. Both subtypes of PA (aldosterone-producing adenoma and bilateral adrenal hyperplasia) had similar effect on BNP production. Specific impact of hyperaldosteronism on BNP was not confirmed.

[Age-related post-translational modification of proteins in human tissue and its use determination of age in forensic medicine. Review]. / Závislost nekterých posttranslacních modifikací proteinu lidských tkání na veku a jejich pouzití pro urcování veku v soudním lékarství. Prehled poznatku.

This article deals with some of posttranslational modification of proteins which are, or could be useful to work out objective and standard methods for age estimation in forensic medicine. From many posttranslational modifications other than racemization, the evaluation of pentosidine, one of the products of nonenzymatic glycosylation, seems to be promising. The enlargement of menu of methods for age estimation is important mainly for forensic sciences when determination of the age of an unknown dead body is necessary. Morphological methods are quite often subjective and charged with errors.

Adipose tissue distribution in obese females. Relationship to androgens, cortisol, growth hormone and leptin.

Adipose tissue distribution predicts development of obesity complications better than total adipose tissue content. The aim of the study was to evaluate the role of the hormonal factors contributing to the adipose tissue distribution in obese females. The cohort examined consisted of 94 women in the range of overweight to obesity, aged 44.2 +/- 11.2 years (21-67), weight 100.1 +/- 17.5 kg (65.8-148), BMI 37.13 +/- 5.72 kg/m2 (26.4-50.7). Adipose tissue (AT) distribution was examined by CT at level L4/5 and intraabdominal adipose tissue and the subcutaneous abdominal adipose tissue area (IAAT and SAAT, respectively) were determined. Growth hormone (GH), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS), cortisol, testosterone, androstene-dione, SHBG, total thyroxine, total triiodothyronine (T3), TSH and leptin were assessed by routine methods by RIA and CLIA. GH, DHEA and DHEA-S correlated significantly negatively with IAAT (r = -0.24, p < 0.05, r = -0.30, p < 0.01, r = -0.34, p < 0.005, respectively). A borderline significant negative correlation of T3 with IAAT was shown (r = -0.20, p = 0.054). A significant positive correlation of SAAT with total testosterone and serum leptin was found (r = 0.27, p < 0.01, r = 0.64, p < 0.001, respectively). When comparing the difference of individual hormone levels between the 1st and 5th quintile of IAAT, no significant difference between the groups was found after adjustment for weight and age. In contrast, when comparing the 1st and 5th quintile according to the SAAT a significantly lower total testosterone and leptin in the 1st quintile of SAAT was found. Only in leptin the difference remained significant after adjustment for adipose tissue content. In conclusion, the results suggest that the relationship of individual hormones examined in this study to the central adipose tissue distribution are mostly mediated by age and adipose tissue content; they do not seem to be in a causal connection with the intraabdominal adipose tissue content. The only exception concerns leptin, which is significantly related to the subcutaneous abdominal adipose tissue area.

Comparison of different immunoassays for CA 19-9.

We compared six routinely employed immunoassay kits: Architect i2000 and AxSYM, Abbott Laboratories; Elecsys 2010, Roche Diagnostics; ELSA, CIS-BioInternational; Immulite 1, Diagnostic Products Corporation; and IRMA-mat, Byk-Sangtec Diagnostica. Using all analytical systems, we measured identical groups of clinical samples completed with selected control samples. The repeatability of measurements (coefficient of variation) ranged from 2.1% (Elecsys 2010) to 6.7% (ELSA). The parameters of Passing-Bablok regression show significant systematic differences among analytical systems. Data from a Bland-Altman diagram suggest that these differences project onto other, still more significant individual differences among individual samples. Though the cut-off values differ between various systems, no similar clinical efficacy appears to be attained. The behavior of individual systems is quite different for identical control materials and does not necessarily duplicate the calibration for biological samples. The results of determining CA 19-9 cannot be extrapolated from one analytical technique to another, even in cases where the same monoclonal antibody is used. Standardization of CA 19-9 measurement systems is necessary to allow use of the results for the purposes of evidence-based medicine.

Can chemiluminescent immunoanalysis of thyroid hormones stand for a reference method?

Some analytical properties of chemiluminescent immunoassays (ChLIA) for the estimation of total triiodothyronine (T3), total thyroxine (T4) and thyrotropine (TSH) in serum were studied and compared with radioimmunoanalysis (RIA) as a reference method. Measurement range of ChLIA for T3 is lower, for T4 is equivalent and for TSH is greater than by RIA methods. Analytical sensitivity of ChLIA is better for all three analytes. Also precision of ChLIA is much better. ChLIA method seems to be more resistant to lipaemia. When compared to secondary reference materials, i.e. to commercial control sera, higher accuracy can be evaluated. However, adjustment of the control sera and analytical methods to different primary standards and calibrators, resulting in disagreement of results with asigned values, seems to be evident. With respect to the accuracy of ChLIA further study should be performed involving primary standards. Other interferences except of lipaemia, which we refer to in our work, and problems of specificity also need to be elucidated.