Air pollution and molecular changes in age-related diseases.

Assessment of the impact that air contaminants have on health is difficult as this is a complex mixture of substances that varies depending on the time and place. There are many studies on the association between air pollution and increased morbidity and mortality. Before the effect of polluted air is manifested at the level of the organs, an impact can be observed at the molecular level. These include some new biomarkers, like a shortening of the mean telomere length in DNA, dysregulation of gene expression caused by microRNA levels or a variation in the copy number of mitochondrial DNA. These changes may predispose individuals to premature development of age-related diseases and consequently to shortening of life. The common attribute, shared by changes at the molecular level and the development of diseases, is the presence of oxidative stress.

Frequency of mutations in BRCA genes and other candidate genes in high-risk probands or probands with breast or ovarian cancer in the Czech Republic.

Breast cancer is currently the most common form of malignant tumour in womenboth in the Czech Republic and in most countries of the western world, and its incidence is constantly increasing. Many risk factors are known to play a major role in the development of this form of cancer. One of them is genetics, especially the BRCA1/2 genes. A higher risk of ovarian cancer is also associated with these genes. With the development of laboratory diagnostics massive parallel sequencing methods (NGS) are now routinely employed, enabling the detection of other pathogenic sequence variants, or variants of uncertain significance (VUS) not previously detected. Besides the high penetrance BRCA1/2 genes, medium and low penetrant genes also come to the fore. There were 2046 probands examined in the study, men and women, mainly from eastern part of the Czech Republic. These were selected for a genetic examination, after meeting indication criteria (probands from high-risk families or with breast or ovarian cancer). From this group only women, 2033 probands, were selected and were given a genetic examination for the possible presence of patogenic sequence variants in BRCA1/2 genes, or other candidate genes. Analyses were conducted in the laboratory using DHPLC or next generation sequencing. MLPA method is used for large rearrangements in genes. From all examined women 212 mutations were detected. The most mutations (128) were found in the BRCA1 gene (60%). In the BRCA2 gene 71 mutations (34%) were found and 13 more mutations (6%) were detected in another candidate genes (CHEK2, PALB2, ERCC4). The most frequent sequence variant was c.5266dupC in the BRCA1 gene. The results show that 72% of women with a confirmed mutation in the BRCA1 gene and 77.5% of women with the sequence variant BRCA2, already had breast cancer and 16.4% of women with BRCA1 and 7% of women with BRCA2 already had ovarian cancer. Only 21 high risk families used the possibility to be tested and had undergone targeted mutation testing. The study results suggest a reflection of the causes and needs for examination of patients and women predisposed to breast or ovarian cancer.

[Frequency view on genome changes testing]. / Frekvencní pohled na vysetrení odchylek genomu.

Laboratories dealing with human genome, both inherited and acquired changes, dispose with similar methods and technology. The spectrum of genetic tests is relatively broad and the number of mutations or variants tested differs substantially. Also the number of examinations carried out in individual laboratories varies. Data presented in the tables come from the year 2004 and indicate the number of examinations requested and number of positive results. Many laboratories mentioned in the registry CZDDNAL (http://www.uhkt.cz/lab_a_vysetreni/nr lab_dna_diag/dna_lab_db) perform the same tests but there is also a great number of tests carried out by only one laboratory. Reasons of the request, cost-effectiveness and clinical utility of genetic testing is being discussed.

[Hemorrhagic complications during warfarin treatment]. / Krvácivé komplikace pri lécbe warfarinem.

Bleeding is probably the major complication of anticoagulant treatment with vitamin K antagonists represented nowadays mostly by warfarin in the Czech Republic. The main risk factors in hemorrhagic complications of warfarinisation are the intensity and instability of the anticoagulant treatment, individual patient characteristics, warfarin interactions with other drugs and the length of the anticoagulant therapy. Severe bleeding in warfarin patients is most effectively brought about by a fast and complete undoing of the anticoagulation effect of the drug employing the prothrombin complex concentrate and slow i.v. vitamin K1 infusion regardless of the reason for the anticoagulation. This approach can secure the minimalisation of the bleeding's negative consequences. A less severe bleeding or asymptomatic increase in the international normalized ratio can be treated effectively by skipping or decreasing of the warfarin dosage and/or oral administration of vitamin K1 (i.v. administration only in selected higher risk cases) that does result only in a partial consolidation of coagulopathy but of such type that the risk of thrombotic event requires. The article's goal is to contribute to the treatment standardization in patients with warfarin overdose and/or with hemorrhagic complications due to warfarin treatment and it is available at www.thrombosis.cz. The guidelines include a ready-reference chart whose objective is immediate and quick crash course in the clinical practice.