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A Hlavatá

Publications and source records attributed to A Hlavatá.

4 recordsLinked to original sources

Assay design and optimization of mutant-enriched PCR based method for detection of K-ras gene mutations in pancreatic carcinoma.

The aim of our work was to develop a fast, reliable and sensitive PCR method to detect K-ras mutations in various clinical samples. There is a need for an unimpeachable method for early diagnosis and/or screening of pancreatic cancer (PC). We optimized and subsequently analyzed four methods based on mutant-enriched PCR for the sensitivity, cost and time expense. Using the selected optimal method we examined codon 12 K- ras mutations in a study population of 59 patients with upper GIT malignancies. Reliability of the genotyping was confirmed by sequencing. By using the best of our modified mutant-enriched PCR methods we achieved sensitivity of 1:1 x 10(5). Further studies are necessary to determine the optimal biological material sampling in PC.

Adenocarcinoma↗

[Variation in manifestations of heteroplasmic mtDNA mutation 8993 T>G in two families].

BACKGROUND: The most frequent manifestations of heteroplasmic mitochondrial DNA (mtDNA) mutation 8993 T > G are Leigh syndrome or NARP syndrome (Neurogenic Muscle Weakness, Ataxia, and Retinitis Pigmentosa). The authors describe heterogeneity of clinical symptoms and results of biochemical and molecular analyses in seven severely clinically affected children from two unrelated families with heteroplasmic mtDNA mutation 8993 T > G. METHODS AND RESULTS: Seven clinically affected children from two unrelated families were born in term after an uneventful pregnancy. The failure to thrive, psychomotor retardation, hypotonic or spastic quadruparesis, hypertrophic cardiomyopathy, hepatopathy and hyperlactacidaemia developed after birth. Five children died in the first year of life during acute respiratory infection, one girl died at the age of 3 months with sudden death syndrome, only one boy with spastic quadruparesis and severe psychomotor retardation survived to the age of 8 years. Molecular analyses in all investigated children and their clinically non-affected mothers revealed the presence of heteroplasmic mtDNA mutation 8993 T > G. Mutated copies of mtDNA molecules in maternal tissues were in the range of 15-22%. The mutation load in all analysed children's tissues was higher than 90%. CONCLUSIONS: A broad spectrum of clinical symptoms may be observed in families with heteroplasmic mtDNA mutations 8993 T > G. Affected children with a mutation load higher than 90% usually do not survive after infancy. In both investigated families, a profound increase in the levels of heteroplasmy of mtDNA mutation 8993 T > G was observed in two subsequent generations.

Ataxia↗

[Peroxisomal hereditary diseases].

Nearly two tens of diseases are known to be caused by impairment of several metabolic functions of peroxisomes, or by deficiency in individual peroxisomal enzymes. With the exception of X-bound adrenoleukodystrophy, all diseases are based on autosomally recessive type of inheritance and a majority of them are characteristic by specific neurologic symptoms. The group of diseases in which patients develop a generalised loss of peroxisomal functions includes: Zellweger's cerebro-hepato-renal syndrome, neonatal adrenoleukodystrophy, infantile Refsum's disease, hyperpipecolic acidaemia. Other diseases, such as rhizomelic chondrodysplasia punctata and Zellweger-like syndrome are accompanied by a deficiency in several enzymatic activities. X-bound adrenoleukodystrophy, pseudo-Zellweger's syndrome, hyperoxaluria 1, adult form of Refsum's disease and acatalasaemia are peroxisomal diseases with a deficiency of a single enzyme. In clinically most severe diseases (generalised loss of peroxisomal functions), the impairment of peroxisomal biogenesis is caused assumedly due to the defect in some of the peroxisomal membrane proteins. The biochemical findings are brought about by insufficiency in such metabolic functions as oxidation of fatty acids with very long chains, oxidation of the phytanic and pipecolic acids, synthesis of cholesterol, bile salts and plasmalogenes. Rhizomelic chondrodysplasia punctata and Zellweger's syndrome are more moderate forms which are dominantly biochemically manifestant by an impairment in the synthesis of plasmalogenes. Among the diseases characterised by a deficiency in individual peroxisomal enzymes, most frequent is the X-bound andrenoleukodystrophy which has several clinical phenotypes manifestant in childhood, as well as a clinically less severe form manifestant in adulthood-adrenomyeloneuropathy. The diagnosis of peroxisomal diseases is performed by use of a wide range of methods (morphological, biochemical, immunochemical and molecular genetic examinations) which enable both postnatal and prenatal diagnostics. (Tab. 1, Ref. 104.)

Humans↗