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Comparative Study 2006; 27(Suppl 2): 86-90 PubMed PMID: 17159787 Citation  Keywords:  Adult, Bystander Effect:radiation effects, Carcinoma:etiology, Computer Simulation, Humans, Lung:radiation effects, Lung Neoplasms:etiology, Models, Biological, Neoplasms, Radiation-Induced, Radon Daughters:toxicity, Risk Factors, Smoking:adverse effects,.   

OBJECTIVES: Exposure to radon and radon decay products represents one of the greatest risks of ionizing radiation from natural sources in some residential and working areas. Recently increasing attention has been paid to accurate estimations of this health risk by using various models.

METHODS: In the presented study, a bystander model was used to predict biological effects of radon products on lung tissue target cells. The model considers radiation response as a superposition of the direct alpha particles hit effect and the bystander (cells communication) effect. Energy deposition in the lung tissue and in the air gap was calculated using the Bethe-Bloch equation. The exponential distribution of radon progenies in the mucous layer of smokers and non-smokers was evaluated.

RESULTS: The excess relative risk value of lung cancer occurrence per unit exposure obtained in our study was ERR/WLM=0.0047 for smokers and ERR/WLM=0.0171 (taking into account the environment in radioactive ore mines) for non-smokers. Other published results give the average excess relative risk values per unit exposure in the dwellings for smokers ERR=0.050 per 100 Bq.m(-3) and for non-smokers ERR=0.198 per 100 B.qm(-3). Results presented in this study are in good agreement with the published epidemiological data on lung cancer incidence for mines and residential areas.

CONCLUSIONS: The bystander model is suitable for radon risk prediction in dwellings and at workplaces (residential and working areas)....

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Comparative Study 2006; 27(Suppl 2): 74-77 PubMed PMID: 17159784 Citation  Keywords:  Anticonvulsants:adverse effects, Congenital Abnormalities:epidemiology, Czech Republic, Developmental Disabilities:chemically induced, Epilepsy:complications, Female, Fetal Death:chemically induced, Humans, Infant, Newborn, Information Services, Pregnancy.   

OBJECTIVES: Care, treatment and follow-up in psychiatric and epileptic pregnant women were compared with women inquiring Czech Teratology Information Service (CZTIS) due to other exposure to drugs during pregnancy.

METHODS: Data were collected by CZTIS, member of European Network of Teratology Information Services from 1996. Exposed groups were compared with pregnant women exposed to drugs which were not classified as major teratogens or hyperthermia. Groups do not vary in age, reproductive history and other parameters.

RESULTS: We observed higher frequency of miscarriage and voluntary termination of pregnancy in the group of psychiatric patients. The number of malformation in prospective follow-up cases was lower than in control group.

CONCLUSIONS: Chronic diseases as epilepsy or psychiatric disorders have to be treated during pregnancy. Women should obtain accurate information about possible risk before pregnancy. Co-operation is needed in these cases. Physicians should keep in mind that appropriate information is to be given to the patient according to her disease, education and comprehension of the problem. If there is any doubt they should organize help for their patients....

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Evaluation Studies 2006; 27(Suppl 2): 69-73 PubMed PMID: 17159783 Citation  Keywords:  Animals, Animals, Newborn, Dietary Supplements, Female, Fetal Hypoxia:chemically induced, Fetal Viability:drug effects, Growth and Development:drug effects, Male, Phenytoin:toxicity, Pregnancy, Pregnancy, Animal, Prenatal Exposure Delayed Effects:preventi.   

OBJECTIVES: The aim of this study was to test the effect of supranutritional dosage of the natural antioxidant vitamin E (VitE) on phenytoin (PHT) induced developmental toxicity and possible long-term effects in rat offspring.

METHODS: PHT (150 mg/kg) was administered by oral gavage daily from day 7 to 18 of gestation and VitE prior to PHT orally on the same days.

RESULTS: PHT administration alone resulted in decreased survival rate and lower body weight of pups on day 21 post partum (PP). Moreover, PHT slightly changed somatic growth and pups failed to present dynamic air righting on days 15-20 PP. VitE supplementation did not alleviate these changes but rather induced persisting body weight reduction on the days 21 PP and 100 PP. We observed also decreased brain wet weight in the PHT and VitE + PHT groups compared to controls.

CONCLUSIONS: We concluded that prenatal supplementation with 500 mg/kg of VitE did not ameliorate the developmental toxicity of PHT and failed to protect postnatal development of rat offspring. Further, in the group supplemented with VitE, the occurrence of persistent body weight gain depression up to adulthood indicates its possible interference with somatic growth regulation....

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Journal Article 2006; 27(Suppl 2): 57-60 PubMed PMID: 17159780 Citation  Keywords:  Adult, Antineoplastic Agents:toxicity, Chromosomes, Human, DNA Damage, DNA-Binding Proteins:genetics, Female, Gene Frequency, Genetic Predisposition to Disease, Humans, Male, Medical Staff, Hospital, Middle Aged, Occupational Diseases:chemically induced, .   

OBJECTIVES: Medical workers in oncological units have chronically been exposed to low doses of cytostatics (C) with potential consequences on DNA and chromosomal integrity. Our study addresses relationships between chromosomal aberrations (CAs), chromosome (CSA), and chromatid (CTA) types and polymorphisms in DNA repair genes XRCC1 and XRCC3.

METHODS: The study was conducted on 72 exposed individuals from hospitals in Martin (HMT; 28 individuals), Ruzomberok (HRK; 31 medical workers) and in Trstená (HTS; 13 individuals), and on 34 unexposed individuals. Conventional cytogenetic analysis was employed for the detection of CAs. XRCC1 and XRCC3 polymorphisms were assayed for by Taqman SNP genotyping assays ("Assay-by-Demand") using Real-Time allelic discrimination on AB 7 500 equipment (all from Applied Biosystems, Foster City, USA).

RESULTS: Higher frequencies of CAs were detected in exposed individuals than in controls (1.78% versus 1.32%, respectively). The frequency of aberrant cells (Ab.c.) was highest among workers from HRK (1.97%), followed by those from HMT and HTS (1.54% and 1.85 %, respectively). In the exposed group a moderately higher frequency of CTA (0.93%) in comparison with CSA (0.85%) was detected. Higher CAs were detected in individuals with homozygous variant polymorphism in XRCC1 exon 10 gene than in those with wild-type genotype (1.87% versus 1.60%). Variant T allele in XRCC3 exon 7 was also associated with higher CAs (1.71% and 1.74%) as compared to the wild-type C allele (1.45%).

CONCLUSIONS: The detection of individuals with increased susceptibility to genotoxic agents enables to take preventive measures during the working process....

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Evaluation Studies 2006; 27(Suppl 2): 23-26 PubMed PMID: 17159772 Citation  Keywords:  Animals, Antioxidants:analysis, Body Weight:drug effects, Bronchoalveolar Lavage Fluid:chemistry, Ceramics:toxicity, Glutathione Peroxidase:analysis, Inhalation Exposure:analysis, Lung:chemistry, Lung Diseases:chemically induced, Male, Mineral Fibers:toxi.   

OBJECTIVES: The programmes of asbestos replacement brought the need to use other fibres for insulation or reinforcement of material. The aim of the presented study was to follow the effect of refractory ceramic fibres (RCF3) alone or in combination with cigarette smoke (CS) on antioxidant status of the lung in experiment on animals. As free radicals are supposed to play a role in pathogenesis of lung diseases and the toxicity of particles has been associated with production of reactive oxygen species, the antioxidant status may serve as marker of lung injury. Our hypothesis was that the effect of combined exposure to RCF3 and CS will be additive or synergic.

DESIGN: Scheme of experiment: Wistar rats were randomly divided into 4 groups per 6 animals: control, intratracheal exposure to 4 mg of RCF3, inhalatory exposure to mainstream of cigarette smoke from 8 standard research 1R1 cigarettes per day, and both intratracheal exposure to RCF3 and inhalatory to CS. The exposure lasted 6 months, the inhalatory exposure was performed 5 times per week. After finishing the exposure bronchoalveolar lavage of lungs was performed and ascorbic acid, superoxide dismutase, glutathione and glutathione peroxidase were determined in lung tissue and cell free fraction of bronchoalveolar lavage fluid (BALF).

RESULTS: The results showed that the most sensitive indicator of changes in antioxidant status was glutathione, which was changed in all groups both in BALF and lung tissue homogenate....

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Journal Article 2006; 27(4): 415-423 PubMed PMID: 16891999 Citation  Keywords:  Adult, Apolipoprotein E2:genetics, Chronic Disease, Dental Amalgam:adverse effects, Dental Restoration, Permanent, Depression:chemically induced, Fatigue:chemically induced, Female, Genetic Predisposition to Disease, Genotype, Humans, Male, Memory Disorde.   

: In a group of 465 patients diagnosed as having chronic mercury toxicity (CMT), 32.3% had severe fatigue, 88.8% had memory loss, and 27.5% had depression. A significant correlation was found between CMT and the Apo-lipoprotein E4 genotype (p=0.001). An investigation into an additional 864 consecutively seen general practice patients, resulted in 30.3% having evidence consistent with CMT, and once again a significant correlation was found with the APO-E4 genotype (p=0.001). Removal of amalgam mercury fillings when combined with appropriate treatment resulted in a significant symptom reduction (p<0.001) to levels reported by healthy subjects....

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Journal Article 2006; 27(4): 401-413 PubMed PMID: 16807526 Citation  Keywords:  Child, Preschool, Developmental Disabilities:chemically induced, Diphtheria-Tetanus-Pertussis Vaccine:adverse effects, Haemophilus Vaccines:adverse effects, Humans, Nervous System Diseases:chemically induced, Thimerosal:adverse effects, United States:epid.   

BACKGROUND: Thimerosal is an ethylmercury-containing compound (49.6% mercury by weight) used as at the preservative level in vaccines (0.005% to 0.01%).

METHODS: Statistical modeling in a meta-analysis epidemiological assessment of the Vaccine Adverse Event Reporting System (VAERS) for neurodevelopment disorders (NDs) reported following Diphtheria-Tetanus-whole-cell-Pertussis (DTP) vaccines in comparison to Diphtheria-Tetanus-whole-cell-Pertussis-Haemophilus Influenzae Type b (DTPH) vaccines (administered: 1994-1997) and following Thimerosal-containing Diphtheria-Tetanus-acellular-Pertussis (DTaP), vaccines in comparison to Thimerosal-free DTaP vaccines (administered: 1997-2000), was undertaken.

RESULTS: Significantly increased adjusted (sex, age, vaccine type, vaccine manufacturer) risks of autism, speech disorders, mental retardation, personality disorders, thinking abnormalities, ataxia, and NDs in general, with minimal systematic error or confounding, were associated with TCV exposure.

CONCLUSION: It is clear from the results of the present epidemiological study and other recently published data associating mercury exposure with childhood NDs, additional ND research should be undertaken in the context of evaluating mercury-associated exposures, especially from Thimerosal-containing vaccines....

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Journal Article 2006; 27(1-2): 128-132 PubMed PMID: 16648788 Citation  Keywords:  Acetylcholine:metabolism, Animals, Blood Glucose:metabolism, Hippocampus:metabolism, Hypoglycemia:chemically induced, Hypoglycemic Agents, Insulin, Male, Microdialysis, Neostriatum:drug effects, Rats, Rats, Wistar,.   

OBJECTIVE: It has been well acknowledged that hypoglycemia induces cognitive impairment. However, the behavior of hippocampal cholinergic system, which is thought to play a key role in cognition, during hypoglycemia remains to be elucidated.

MATERIALS AND METHODS: In this study we conducted a microdialysis using 9 weeks old virgin male Wistar/ST rats to determine the changes of extracelluar acethylcholine and glucose levels in the hippocampus during insulin-induced severe hypoglycemia, and compared the results with those obtained from a microdialysis in the striatum.

RESULTS: The extracelluar concentrations of acethylcholine both in the hippocampus and striatum did not change during hypoglycemia.

CONCLUSION: The results of the present study may suggest that changes of hippocampal cholinergic release may not be involved in the mechanism of cognitive impairment during hypoglycemia....

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