Pyridinium crosslinks of collagen as a marker of bone resorption rates in children and adolescents: Normal values and clinical application

The aim of our study was to establish normal values of urinary pyridinoline (Pyr) and deoxypyridinoline (DPyr) excretion for children aged 3–18 years, examine the biological variability of the marker, and assess its clinical value for pediatric patients with growth hormone deficiency. Pyr and DPyr was measured in first void urine samples from 692 healthy subjects (340 boys, 352 girls) by high-performance liquid chromatography. At sampling, age, body height, and weight was recorded for all individuals. Short-term variability in crosslinks excretion was examined in four healthy children. The clinical value of the marker was studied in seven patients with growth hormone (GH) deficiency. In childhood, crosslinks excretion exceeded normal adult values by about fivefold and declined during puberty. In the age range of 13–18 years, gender-related differences in Pyr and DPyr levels were observed, presumably resulting from the earlier onset of puberty in girls. Urinary levels of Pyr and DPyr were highly correlated both in males and females. Pyr/DPyr ratio was significantly higher in adolescents than children, suggesting enhanced release of Pyr from extraosseous sources. In both genders, neither age nor anthropometric variables showed a linear effect on crosslinks excretion. The range of within-subject, short-term variability in urinary Pyr and DPyr was relatively high (CV: 6%–21%), indicating that single measurements of crosslinks excretion may not adequately reflect bone resorption rates in children. Pyr and DPyr levels were significantly lower in GH-deficient patients and normalized during human growth hormone (hGH) therapy. Significant correlations between growth velocity (GV) and crosslinks levels were found, but individual prediction of GV increment during hGH treatment may be inaccurate. Pyr/DPyr ratio was not related to GV. It is concluded that measurement of urinary Pyr and DPyr excretion in children may be a valuable tool to assess bone resorption rates in population-based studies. In individual patients, however, only qualitative evaluation of disease severity and response to treatment seems justified.     

The effect of sulphinpyrazone and alpha-tocopherol on platelet activation and function in haemodialysed patients

In 30 patients on chronic haemodialysis treatment the platelet activity and function were studied before and during antiplatelet therapy with alpha-tocopherol and sulphinpyrazone. In both kinds of treatment a significant decrease of ADP-induced and spontaneous aggregation was observed. Sulphinpyrazone exerts an inhibitory effect not only on platelet aggregation but also on platelet factor 3 and provokes a significant prolongation of the bleeding time.     

Seven DNA polymorphisms in the LDL receptor gene: application to the study of familial hypercholesterolemia in Spain

We have performed restriction fragment length polymorphism (RFLP) analysis at the low density lipoprotein receptor (LDLR) locus in order to investigate the molecular genetics of familial hypercholesterolemia (FH) in Spain. Firstly, a sample of 50 unrelated patients with a clinical diagnosis of FH was screened for the presence of major rearrangements at this locus by Southern blot analysis of Bgt II digested genomic DNA. Four different mutations were detected, accounting for 8% of the mutant alleles in the Spanish FH sample. Then, we determined the relative allele frequency and estimated linkage disequilibrium between seven RFLPs of the LDLR gene in the remaining 46 FH patients and in 61 normolipidemic controls. Hindi, Avail, Pvu II, Msp I, and Nco I are the most polymorphic sites with individual PIC values higher than 0.28, whereas the Taq I and Stu I sites display low levels of polymorphism. The usefulness of the seven RFLPs to confirm a clinical diagnosis of FH was investigated in 15 FH-families, consisting of 118 individuals, in whom the presence of Familial Defective Apolipoprotein B-100 (FDB) due to the apoB₃₅₀₀ mutation was excluded. Independent haplotypes were constructed for 71 chromosomes: 15 FH and 56 control haplotypes. A total of 14 different haplotypes was found. In 12 families, clinical diagnosis of FH was confirmed by cosegregation analysis, which makes these RFLPs useful for studying the inheritance of the LDLR gene in 80% of Spanish families with FH. Comparison of haplotypes found in the Spanish sample with those found in Swiss and Norwegians suggests heterogeneity of haplotypes among European populations.     

Inhibitory effect of tritoqualine on activation of latent polymorphonuclear leukocyte collagenase

Treatment of rats with histamine releaser compound 48/80 caused changes in blood leukocyte populations. An increased number of PMN-leukocytes was observed. Tritoqualine only modestly reduced the number of granulocytes. In animals treated with compound 48/80 an activation of PMN-leukocyte latent collagenase of up to 80% was observed. This activation was partially inhibited (about 40%) in animals pretreated with tritoqualine. The results presented suggest that the beneficial effect of tritoqualine in allergic diseases may be in part connected with an indirect inhibition of collagenase activity.     

The role of calcium ions and inositol phospholipids in platelet activation]

The present state of knowledge on the importance of calcium ions and inositol phospholipids in the metabolic changes associated with early stages of platelet activation is outlined, with stress laid in the biochemical mechanisms of intracellular rise of calcium ion concentration. The metabolism of inositol phospholipids is briefly discussed stressing the importance of the metabolites of these phospholipids--1,2-diacylglycerol and 1,4,5-inositol triphosphate which are of key importance in the transfer of information between platelet membrane and intracellular structures.     

Serological conflict: relation between antibody titer, Liley's zone and the condition of the fetus and newborn infant]

On the basis of analysis of 128 cases of serological incompatibility it was found that antibodies to Rh in titres of 1/8 or less constituted a good prognostic factor, and without evidence of fetal distress in USG examination this was not an indication to treatment undertaking. If the titre is from 1/16 to 1/128 the prognosis is worse and the degree of fetal haemolytic disease risk may be estimated on the basis of USG and Liley's zone. The prognosis is very bad in case of titre exceeding 1/128 and high Liley's zone, and without effective treatment of haemolytic disease in fetal life only few fetuses survive.     

Long-term results of treatment for articular calcaneus fractures with Westhues method]

In this paper the authors evaluate the long-term results of treatment for articular calcaneus fractures with Westhues method. This evaluation is performed with regard to triple measurement of B?hler's angle value and to subjective criteria. The clinical material from years 1985-2002 consists of 47 patients aged between 24 and 56 years (mean age 32 years) with articular calcaneus fractures--namely, 41 male patients (87.2%) and 6 female patients (12.8%). The follow-up examination was performed in 24 patients (51% of all patients), namely, in 23 male patients (48.8%) and in one female patient (2.2%). Minimum follow-up time was 12 months and maximum was 9 years. Acquired results suggest that Westhues method restores normal B?hler's angle value only in tongue-type calcaneous fractures.