Ciril Krzisnik

High prevalence of thyroid peroxidase gene mutations in patients with thyroid dyshormonogenesis

OBJECTIVE Thyroid dyshormonogenesis is a genetically heterogeneous group of inherited disorders in the enzymatic cascade of thyroid hormone synthesis that result in congenital hypothyroidism (CH). Thyroid peroxidase gene (TPO) mutations are one of the most common causes of thyroid dyshormonogenesis. The aim of this study was to identify TPO gene defects in a cohort of patients with thyroid dyshormonogenesis from Slovenia, Bosnia, and Slovakia. DESIGN AND METHODS Forty-three patients with permanent CH and orthoptic thyroid glands from 39 unrelated families participated in the study. Mutational analysis of the TPO gene and part of its promoter consisted of single-stranded conformation polymorphism analysis, sequencing, and restriction fragment length polymorphism (RFLP) analysis. RESULTS TPO gene mutations were identified in 46% of participants. Seven different mutations were identified, four mutations of these being novel, namely 613C > T (R175X), 1519_1539del (A477_N483del), 2089G > A (G667S), and 2669G > A (G860R). Only a single allele mutation was identified in 65% of the TPO mutation carriers. CONCLUSIONS The results showed a higher prevalence of TPO gene mutations in thyroid dyshormonogenesis when compared with published studies. The high percentage of single allele mutations implied possible intronic or regulatory TPO gene mutations or monoallelic expression.

Cardiac damage after treatment of childhood cancer: A long-term follow-up

BackgroundWith improved childhood cancer cure rate, long term sequelae are becoming an important factor of quality of life. Signs of cardiovascular disease are frequently found in long term survivors of cancer. Cardiac damage may be related to irradiation and chemotherapy.We have evaluated simultaneous influence of a series of independent variables on the late cardiac damage in childhood cancer survivors in Slovenia and identified groups at the highest risk.Methods211 long-term survivors of different childhood cancers, at least five years after treatment were included in the study. The evaluation included history, physical examination, electrocardiograpy, exercise testing and echocardiograpy. For analysis of risk factors, beside univariate analysis, multivariate classification tree analysis statistical method was used.Results and ConclusionPatients treated latest, from 1989–98 are at highest risk for any injury to the heart (73%). Among those treated earlier are at the highest risk those with Hodgkins disease treated with irradiation above 30 Gy and those treated for sarcoma. Among specific forms of injury, patients treated with radiation to the heart area are at highest risk of injury to the valves. Patients treated with large doses of anthracyclines or concomitantly with anthracyclines and alkylating agents are at highest risk of systolic function defect and enlarged heart chambers. Those treated with anthracyclines are at highest risk of diastolic function defect. The time period of the patients treatment is emerged as an important risk factor for injury of the heart.

Tumor necrosis factor-α alters glucose metabolism in suckling rats

Abstract Tumor necrosis factor-α (TNF-α), an important mediator of endotoxic shock, induces hypoglycemia and shock in adult animals. Indomethacin ameliorates TNF-α–induced hypoglycemia in the adult. However, effects of TNF-α on glucose metabolism in the newborn have not been well documented. The present study showed that in 10-day-old rats injected with TNF-α (4.5 × 107 U/kg, intraperitoneally) the plasma glucose concentration increased from 4.1 ± 0.3 mmol/L to 6.9 ± 0.5 mmol/L (P

TISSUE GLUCOSE TRANSPORT AND GLUCOSE TRANSPORTERS IN SUCKLING RATS WITH ENDOTOXIC SHOCK

ABSTRACT Hypoglycemia occurs without hyperinsulinemia in suckling rats with endotoxic shock. However, tissue glucose uptake during endotoxic shock is not well known in the newborn. GLUT1 is insulin insensitive and is the predominant glucose transporter in 10 day old rats. In the adult with endotoxic shock, noninsulin-mediated glucose uptake and GLUT1 gene expression increase. Therefore, we hypothesized that tissue glucose uptake and GLUT1 mRNA abundance increased in 10 day old rats with endotoxic shock. The present study showed that whole body glucose disposal increased 3 h after a Salmonella enteritidis lipopolysaccharide injection (LD90 at 72 h). Plasma insulin concentration was not altered. Tissue glucose uptake increased in liver (2.4-fold) and fat (2.6-fold). However, changes of GLUT1 protein concentration were not detected in liver. GLUT1 mRNA abundance increased in liver (9-fold) and fat (4-fold). GLUT1 mRNA abundance but not glucose uptake increased in muscle. Neither glucose uptake or GLUT1 mRNA abundance was altered in brain. The mRNA abundance of tissue-specific glucose transporters (GLUT2 and GLUT4) was not altered. Thus, tissue glucose uptake and GLUT1 mRNA abundance increased without hyperinsulinemia during endotoxic shock in 10 day old rats.

Five year treatment with IGF-I of a patient with Laron syndrome in Slovenia (a follow-up report).

This is a follow-up report of a 14 1/2 year-old boy with Laron syndrome, who received twice daily therapy with IGF-I 120 micrograms/kg for 5 years that resulted in a linear growth of 40 cm. Concomitantly he became very obese which is attributed to IGF-I action via the insulin receptors.

Frequencies of Q188R and N314D mutations and IVS5-24g>A intron variation in the galactose-1-phosphate uridyl transferase (GALT) gene in the Slovenian population.

Abstract Numerous mutations in the galactose-1-phosphate uridyl transferase (GALT) gene have been found to impair GALT activity to different extent, causing galactosemia. This disorder exhibits considerable allelic heterogeneity in different populations and ethnic groups. The Q188R mutation accounts for 60–70% of classical galactosemia alleles in the Caucasian population. Individuals homoallelic for Q188R have a severe phenotype with complete loss of enzyme activity. Another form of GALT deficiency is Duarte galactosemia with N314D mutation associated alleles (Duarte-2). Although heterozygotes for classical galactosemia are asymptomatic at birth and Duarte galactosemia appears to be quite benign, there are some indications that these disorders can increase the risk of developing certain diseases later in life. The aim of our study was to analyze a healthy Slovenian population for the frequencies of Q188R and N314D mutations, and for the Duarte-2 indicative intronic variation IVS5-24G>A. DNA samples from 174 healthy subjects were analyzed for all three mutations by polymerase chain reaction and digestion with restriction enzymes. Allele frequencies for Q188R and N314D mutations and IVS5-24G>A intron variation were found to be 0.29%, 8.0% and 5.7%, respectively. These results correlate well with those reported for most other healthy Caucasian populations.

Lack of association of common allelic variants in the thyroglobulin gene with Hashimoto's thyroiditis in young subjects with type 1 diabetes.

Background/Aim: Four SNPs (E10SNP24, E10SNP158, E12SNP, E33SNP) in the Tg gene are suspected to be involved in the development of autoimmune thyroid diseases. The aim of the study was to determine whether these variants play a role in the development of Hashimoto’s thyroiditis in young subjects with type 1 diabetes, in whom autoimmune thyroid diseases are significantly more common than in the general population. Subjects and Methods: Seventy-six subjects with type 1 diabetes and Hashimoto’s thyroiditis and 110 subjects with only type 1 diabetes were studied. Hashimoto’s thyroiditis was determined according to the clinical, biochemical and ultrasonographic criteria. SNPs were determined by the TaqMan SNP method. Results: In young subjects with type 1 diabetes, no association between any of the tested SNPs or their combinations and Hashimoto‘s thyroiditis was found. Conclusions: This is the first study to investigate the association of SNPs located inside the coding region of the Tg gene with the development of Hashimoto’s thyroiditis in subjects with type 1 diabetes. The lack of an association is in concordance with a study where marker Tgms2, located inside intron 27, was not associated with joint susceptibility for autoimmune thyroid disease and type 1 diabetes.