Hyperbaric oxygen enhances collagen III formation in wound of ZDF rat.

Diabetic foot ulcer (DFU) is a serious complication of diabetes and hyperbaric oxygen therapy (HBOT) is also considered in comprehensive treatment. The evidence supporting the use of HBOT in DFU treatment is controversial. The aim of this work was to introduce a DFU model in ZDF rat by creating a wound on the back of an animal and to investigate the effect of HBOT on the defect by macroscopic evaluation, quantitative histological evaluation of collagen (types I and III), evaluation of angiogenesis and determination of interleukin 6 (IL6) levels in the plasma. The study included 10 rats in the control group (CONT) and 10 in the HBOT group, who underwent HBOT in standard clinical regimen. Histological evaluation was performed on the 18th day after induction of defect. The results show that HBOT did not affect the macroscopic size of the defect nor IL6 plasma levels. A volume fraction of type I collagen was slightly increased by HBOT without reaching statistical significance (1.35+/-0.49 and 1.94+/-0.67 %, CONT and HBOT, respectively). In contrast, the collagen type III volume fraction was ~120 % higher in HBOT wounds (1.41+/-0.81 %) than in CONT ones (0.63+/-0.37 %; p=0.046). In addition, the ratio of the volume fraction of both collagens in the wound ((I+III)w) to the volume fraction of both collagens in the adjacent healthy skin ((I+III)h) was ~65 % higher in rats subjected to HBOT (8.9+/-3.07 vs. 5.38+/-1.86 %, HBOT and CONT, respectively; p=0.028). Vessels density (number per 1 mm2) was found to be higher in CONT vs. HBOT (206.5+/-41.8 and 124+/-28.2, respectively, p<0.001). Our study suggests that HBOT promotes collagen III formation and decreases the number of newly formed vessels at the early phases of healing.

Hyperbaric oxygen influences chronic wound healing - a cellular level review.

Chronic wound is a serious medical issue due to its high prevalence and complications; hyperbaric oxygen therapy (HBOT) is also considered in comprehensive treatment. Clinical trials, including large meta-analyses bring inconsistent results about HBOT efficacy. This review is summarizing the possible effect of HBOT on the healing of chronic wound models at the cellular level. HBOT undoubtedly escalates the production of reactive oxygen and nitrogen radicals (ROS and RNS), which underlie both the therapeutic and toxic effects of HBOT on certain tissues. HBOT paradoxically elevates the concentration of Hypoxia inducible factor (HIF) 1 by diverting the HIF-1 degradation to pathways that are independent of the oxygen concentration. Elevated HIF-1 stimulates the production of different growth factors, boosting the healing process. HBOT supports synthesis of Heat shock proteins (HSP), which are serving as chaperones of HIF-1. HBOT has antimicrobial effect, increases the effectiveness of some antibiotics, stimulates fibroblasts growth, collagen synthesis and suppresses the activity of proteolytic enzymes like matrix metalloproteinases. All effects of HBOT were investigated on cell cultures and animal models, the limitation of their translation is discussed at the end of this review.

Norepinephrine turnover in the left ventricle of subtotally nephrectomized rats.

Increased activity of the sympathetic nervous system (SNS) has been proposed as a risk factor for increased cardiovascular mortality in patients with chronic kidney disease (CKD). Information on the activity of cardiac sympathetic innervation is non-homogeneous and incomplete. The aim of our study was to evaluate the tonic effect of SNS on heart rate, norepinephrine turnover and direct and indirect effects of norepinephrine in left ventricles of subtotally nephrectomized rats (SNX) in comparison with sham-operated animals (SHAM). Renal failure was verified by measuring serum creatinine and urea levels. SNX rats developed increased heart rates and blood pressure (BP). The increase in heart rate was not caused by sympathetic overactivity as the negative chronotropic effect of metipranolol did not differ between the SNX and SHAM animals. The positive inotropic effects of norepinephrine and tyramine on papillary muscle were not significantly different. Norepinephrine turnover was measured after the administration of tyrosine hydroxylase inhibitor, pargyline, tyramine, desipramine, and KCl induced depolarization. The absolute amount of released norepinephrine was comparable in both groups despite a significantly decreased norepinephrine concentration in the cardiac tissue of the SNX rats. We conclude that CKD associated with renal denervation in rats led to adaptive changes characterized by an increased reuptake and intracellular norepinephrine turnover which maintained normal reactivity of the heart to sympathetic stimulation.

Variability of mitochondrial respiration in relation to sepsis-induced multiple organ dysfunction.

Ample experimental evidence suggests that sepsis could interfere with any mitochondrial function; however, the true role of mitochondrial dysfunction in the pathogenesis of sepsis-induced multiple organ dysfunction is still a matter of controversy. This review is primarily focused on mitochondrial oxygen consumption in various animal models of sepsis in relation to human disease and potential sources of variability in experimental results documenting decrease, increase or no change in mitochondrial respiration in various organs and species. To date, at least three possible explanations of sepsis-associated dysfunction of the mitochondrial respiratory system and consequently impaired energy production have been suggested: 1. Mitochondrial dysfunction is secondary to tissue hypoxia. 2. Mitochondria are challenged by various toxins or mediators of inflammation that impair oxygen utilization (cytopathic hypoxia). 3. Compromised mitochondrial respiration could be an active measure of survival strategy resembling stunning or hibernation. To reveal the true role of mitochondria in sepsis, sources of variability of experimental results based on animal species, models of sepsis, organs studied, or analytical approaches should be identified and minimized by the use of appropriate experimental models resembling human sepsis, wider use of larger animal species in preclinical studies, more detailed mapping of interspecies differences and organ-specific features of oxygen utilization in addition to use of complex and standardized protocols evaluating mitochondrial respiration.

Repeated exposure to hyperbaric hyperoxia affects mitochondrial functions of the lung fibroblasts.

Hyperbaric oxygen (HBO) therapy, i.e. breathing pure oxygen under increased environmental pressures serves as a treatment for diverse medical conditions. However, elevated oxygen concentration can be detrimental to central nervous system or lungs. Our study aimed to evaluate the effects of repeated exposure to HBO on mitochondrial respiration assessed by high-resolution respirometry (HRR), cell viability estimated by PrestoBlue® reaction, morphology analyzed by routine phase contrast and fluorescent microscopy, and superoxide dismutase (SOD) and citrate synthase (CS) activities using human lung fibroblasts. The cells were exposed to HBO for 2 h per day for 5 consecutive days. One day after the last exposure, HBO cells displayed significantly smaller area and perimeter, compromised viability and elevated SOD activity. No changes were detected in CS activity or quality of mitochondrial network. HRR revealed impaired mitochondrial oxygen consumption manifested by increased leak respiration, decreased activity of complex II and compromised ATP-related oxygen consumption when fatty acids were oxidized. Our findings document that in conditions mimicking chronic intermittent exposure to HBO, lung fibroblasts suffer from compromised mitochondrial respiration linked to complex II and impaired cellular growth in spite of increased antioxidant defense. Underlying mechanism of this HBO-induced mitochondrial dysfunction should be further explored.

[Environmental pollution and childhood morbidity]. / Znecistené ovzdusí a nemocnost detí.

BACKGROUND: A study of morbidity of children aged 0 to 3 years was organized in two districts in the Czech Republic. Comparisons were drawn between children living in district Teplice, known for its high air pollution, and those living in Practice, the district with consistently lower particulate and SO2 exposures. METHODS AND RESULTS: 452 children of the follow up study were born between May 1994 and December 1996. Childhood morbidity during the first three years of life was obtained from their pediatric records. Diagnoses were coded using the International Classification of Diseases--the 10th edition, and categorized into broad groups. Children born in Teplice experienced a significantly higher rate of otitis media (and otalgia), gastrointestinal infections, upper respiratory infections, and pneumonia, but they did not differ in the risk of bronchitis or that of viral infections such as varicella. These findings remained valid after the multiple linear regression models were calculated and adjusted for education, maternal age, maternal smoking, and other smokers in the household, breastfeeding, and attendance at the day care. CONCLUSIONS: Air pollution may alter early childhood susceptibility to infection, but other differences between the districts have to be considered: systematic diagnostic differences for several health outcomes between pediatricians in Teplice and Practice, differences in health-care seeking approach of parents, and some hitherto unidentified factors.

Childhood morbidity and air pollution in the Teplice program.

BACKGROUND: A study of morbidity of children aged 0 to 3 years was conducted in two districts in the Czech Republic. Comparisons were made between children living in Teplice district, known for its high air pollution, and children living in Practice, a district with consistently lower particulate and SO2 exposures. METHODS AND RESULTS: The children were selected for the follow up based on deliveries from May 1994 to December 1966. Childhood morbidity during the first three years of life of 452 children was extracted from their pediatric records. Diagnoses were coded using the International Classification of Diseases--10th edition, and categorized into broad groupings. Children born in Teplice experienced a significantly higher rate of otitis media and otalgia, gastrointestinal infections, upper respiratory infections, and pneumonia, but did not differ in their risk for bronchitis or for viral infections such as varicella. These findings remained after multiple linear regression models adjusted for education, maternal age, maternal smoking, and other smokers in the household, breastfeeding, and attendance at day care. CONCLUSIONS: Air pollution may alter early childhood susceptibility to infection, but other differences between the districts must be considered: systematic diagnostic differences for several health outcomes comparing pediatricians in Teplice vs. Practice, differences in health-care seeking behavior by the parents, and inadequate control for confounding.

[Maternal exposure to dust particles during pregnancy and fetal growth in 2 regions with different levels of air pollution]. / Expozice matky prachovým cásticím tehotenství a rust plodu ve dvou regionech s rozdílnou úrovní znecisteného ovzdusí.

BACKGROUND: Recently, an association between adverse pregnancy outcome and air pollution was hypothesized in several papers. The aim of the present study is to evaluate the impact of particles with aerodynamic diameter < or = 10 microns (PM10) on the intrauterine growth retardation (IUGR) in two regions with the different levels of air pollution. METHODS AND RESULTS: The study group includes all singleton full term births of European origin over a two-year period in the district of Teplice (n = 1,943) and Prachatice (n = 883). Information on reproductive and health history and lifestyle was obtained from maternal questionnaires and medical records. IUGR was chosen as the indicator of reproductive effects. The mean concentration of PM10 for each women in particular gestational month was calculated. Three concentration intervals were constructed (low < 40 micrograms/m3; medium 40-50 micrograms/m3; high > or = 50 micrograms/m3). Relative risk of IUGR was estimated for particular month and pollutant level. Influence of the potential confounders (maternal age, height and pre-pregnancy weight, smoking, season and the year of study) was controlled using logistic regression models; adjusted odd's ratio (AOR) was estimated. Relative risk of IUGR in Teplice District was increased for medium PM10 levels (AOR = 1.62 CI: 1.07-2.46) (P < 0.02) as well as for high levels in the first gestational month (2.64 CI: 1.48-4.71) (P < 0.001). The same association was observed also in Prachatice District, though the PM10 did not achieve the "high" levels (> or = 50 micrograms/m3). AOR for IUGR for mothers exposed in the 1st gestational month to medium PM10 levels was three times the risk of those exposed to low levels (3.50 CI: 1.82-6.81) (P < 0.0003). No similar relationship was observed in any other gestational stage. CONCLUSIONS: Influence of particles or other associated air pollutants on fetal growth in early gestation is one of several possible explanations of these results. Timing of this effect in both different regions is compatible with a current hypothesis of IUGR etio-pathogenesis. Seasonal factors, one of the other possible explanations, is less probable. More investigation is required to evaluate a possible causal nature of the relationship observed.

[Parameters of cellular immunity in maternal and umbilical cord blood in relation to air pollution. Preliminary results of a pregnancy outcomes study]. / Parametry bunecné imunity v materské a pupecníkové krvi ve vztahu k znecistení ovzdusí. Predbezné výsledky projektu výsledky tehotenství.

BACKGROUND: The study is a part of the project Pregnancy Outcome (Teplice Program) examining effects of polluted environment on the quality of reproduction in Teplice (high polluted) and Prachatice (control) districts. Selected parameters of cell mediated and humoral immunity in maternal and umbilical samples after delivery were assayed. METHODS AND RESULTS: Lymphocytes in 768 samples of maternal venous blood and 739 samples of umbilical blood collected in May 1994-October 1997 were phenotyped using flow cytometry. Medical and personal questionnaires were used to obtain data on clinical risk factors during pregnancy, health and life style of mothers, the course and prolongation of labour and newborn's status. The percentages of T and NK lymphocytes in both umbilical and maternal blood were associated with a number of variables, including the course of labour. After adjustment for the other predictors, the percentage of NK lymphocytes was found significantly higher in Teplice than in Prachatice samples--in both maternal and umbilical blood. CONCLUSIONS: A part of the observed difference between distribution of NK and T lymphocytes can be attributed to living in the polluted district. To see effects of polluted environment, the association of seasonal difference in levels of major pollutants with seasonal changes in lymphocyte phenotype will be analyzed.

Fecundability and parental exposure to ambient sulfur dioxide.

Recently it has been observed that birth rates in Teplice, a highly polluted district in Northern Bohemia, have been reduced during periods when sulfur dioxide levels were high. This study, which is based on data from 2,585 parental pairs in the same region, describes an analysis of the impact of SO(2) on fecundability in the first unprotected menstrual cycle (FUMC). We obtained detailed personal data, including time-to-pregnancy information, via maternal questionnaires at delivery. We estimated individual exposures to SO(2) in each of the 4 months before conception on the basis of continual central monitoring. Three concentration intervals were introduced: < 40 microg/m(3 )(reference level); 40-80 microg/m(3); and [greater than or equal to] 80 microg/m(3). We estimated adjusted odds ratios (AORs) of conception in the FUMC using logistic regression models. Many variables were screened for confounding. AORs for conception in the FUMC were consistently reduced only for couples exposed in the second month before conception to SO(2) levels as follows: 40-80 microg/m(3), AOR 0.57 [95% confidence interval (CI), 0.37-0.88; p < 0.011]; [greater than or equal to] 80 microg/m(3), AOR 0.49 (CI, 0.29-0.81; p < 0.006). The association was weaker in the second 2 years of the study, probably due to the gradual decrease of SO(2) levels in the region. The relationship between SO(2) and fecundability was greater in couples living close to the central monitoring station (within 3.5 km). The timing of these effects is consistent with the period of sperm maturation. This is in agreement with recent findings; sperm abnormalities originating during spermatid maturation were found in young men from Teplice region who were exposed to the increased levels of ambient SO(2). Alternative explanations of our results are also possible.

The impact of polycyclic aromatic hydrocarbons and fine particles on pregnancy outcome.

The relationship between intrauterine growth retardation (IUGR) and exposure to particulate matter [less than/equal to] 10 microm (PM(10)) and particulate matter [less than and equal to] 2.5 microm (PM(2.5))( )in early pregnancy was recently studied in the highly polluted district of Teplice (Northern Bohemia). From this observation rose the question about the possible role of the carcinogenic fraction of polycyclic aromatic hydrocarbons (c-PAHs), which are usually bound to fine particles. The impact of c-PAHs and fine particles on IUGR was analyzed in Teplice and in Prachatice, a region with similarly high c-PAH but low particle levels. All European, single live births occurring in a 4-year period in Teplice (n = 3,378) and Prachatice (n = 1,505) were included. Detailed personal data were obtained via questionnaires and medical records. Mean PM(10), PM(2.5,) and c-PAHs levels during the 9 gestational months (GM) were estimated for each mother. Adjusted odds ratios (AORs) of IUGR for three levels of c-PAHs (low, medium, and high) and for continuous data were estimated after adjustment for a range of covariates using logistic regression models. In the present 4-year sample from Teplice, previously published results about increasing IUGR risk after exposure to particles in the first GM were fully confirmed, but no such effects were found in Prachatice. The AOR of IUGR for fetuses from Teplice exposed to medium levels of c-PAHs in the first GM was 1.60 [confidence interval (CI), 1.06-2. 15], and to high levels 2.15 (CI, 27-3.63). An exposure-response relationship was established by analyzing the continuous data. For each 10 ng increase of c-PAHs in the first GM, the AOR was 1.22 (CI, 1.07-1.39). About the same relationship was observed in Prachatice in spite of the low particle levels. The results prove that exposure to c-PAHs in early gestation may influence fetal growth. The particulate matter-IUGR association observed earlier may be at least partly explained by the presence of c-PAHs on particle surfaces.

Adverse reproductive outcomes from exposure to environmental mutagens.

The effect of environmental pollution on reproductive outcomes has been studied in the research project 'Teplice Program' analyzing the impact of air pollution on human health. Genotoxicity of urban air particles <10 microm (PM10) in in vitro system was determined by the analysis of DNA adducts. The highest DNA binding activity was observed in aromatic fraction, identifying DNA adducts of carcinogenic polycyclic aromatic hydrocarbons (PAHs) presumably diolepoxide-derived from: 9-hydroxybenzo[a]pyrene (9-OH-B[a]P), benzo[a]pyrene-r-7,-dihydrodiol-t-9,10-epoxide[+] (anti-BPDE), benzo[b]fluoranthene (B[b]F), chrysene (CHRY), benz[a]antracene (B[a]A), indeno[1,2,3-cd]pyrene (I[cd]P). Reproductive studies were conducted in both females and males. A study of the effects of PM10 exposure on pregnancy outcomes found the relationship between the intrauterine growth retardation (IUGR) and PM10 levels over 40 microg/m(3) in the first gestational month (Odds Ratio for 40-50 microg/m(3)50 microg/m(3)=1.9). Selected biomarkers were analyzed in venous blood, cord blood (chromosomal aberrations, comet assay) and placenta (DNA adducts, genetic polymorphisms of GSTM1 and NAT2 genotypes) of women enrolled in a nested case-control study. DNA adduct levels were higher in polluted vs. control districts, in smoking vs. nonsmoking mothers, and in GSTM1 null genotype, which was more pronounced in polluted district. No effect of air pollution was observed by cytogenetic analysis of chromosomal aberrations or by comet assay. The reproductive development of young men was followed by measures of semen quality, adjusted for ambient SO(2) exposure. The analysis identified significant associations with air pollution for <13% morphologically normal sperm, <29% sperm with normal head shape, <24% motile sperm. Analysis of aneuploidy in human sperm by FISH showed, aneuploidy YY8 was associated with season of heaviest air pollution. These findings are suggestive for an influence of air pollution on YY8 disomy. All these results indicate that air pollution may increase DNA damage in human population, which may be even higher for susceptible groups. Biomarkers of exposure (DNA adducts) and susceptibility (GSTM1 and NAT2) may indicate the risk of presumable low environmental exposure. Pregnancy outcome and semen studies imply that relatively low air pollution (higher than 40 microg PM10/m(3)) can significantly increase the adverse reproductive outcomes affecting both genders.

Fetal growth and maternal exposure to particulate matter during pregnancy.

Prior studies reported an association between ambient air concentrations of total suspended particles and SO2 during pregnancy and adverse pregnancy outcomes. We examined the possible impact of particulate matter up to 10 microm (PM10) and up to 2.5 microm (PM2. 5) in size on intrauterine growth retardation (IUGR) risk in a highly polluted area of Northern Bohemia (Teplice District). The study group includes all singleton full-term births of European origin over a 2-year period in the Teplice District. Information on reproductive history, health, and lifestyle was obtained from maternal questionnaires. The mean concentrations of pollutants for each month of gestation were calculated using continuous monitoring data. Three intervals (low, medium, and high) were constructed for each pollutant (tertiles). Odds ratios (ORs) for IUGR for PM10 and PM2.5 levels were generated using logistic regression for each month of gestation after adjustment for potential confounding factors. Adjusted ORs for IUGR related to ambient PM10 levels in the first gestational month increased along the concentration intervals: medium 1.62 [95% confidence interval (CI), 1.07-2.46], high 2.64 (CI, 1.48-4.71). ORs for PM2.5 were 1.26 (CI, 0.81-1.95) and 2.11 (CI, 1. 20-3.70), respectively. No other associations of IUGR risk with particulate matter were found. Influence of particles or other associated air pollutants on fetal growth in early gestation is one of several possible explanations of these results. Timing of this effect is compatible with a current hypothesis of IUGR pathogenesis. Seasonal factors, one of the other possible explanations, is less probable. More investigation is required to examine these findings and alternative explanations.

Single cell gel electrophoresis assay: sensitivity of peripheral white blood cells in human population studies.

The single cell gel electrophoresis assay (Comet assay) was selected as a biomarker of exposure to evaluate the impact of air pollution and lifestyle variables on hospitalized pregnancies in two districts with different air pollution levels in northern (Teplice) and southern (Prachatice) Bohemia. The hypothesis was that the DNA damage detected as single strand breaks would be generally higher in the district with higher air pollution levels. To undertake the study we enrolled 322 pregnancies in Teplice and 220 in Prachatice. Venous and cord blood were analysed using the original alkaline Comet assay procedure with lysis for 60 min, unwinding for 40 min and electrophoresis for 24 min. We also used a modified procedure in which unwinding was prolonged to 60 min and electrophoresis to 40 min. Peripheral white blood cells (WBC) were analysed using an image analyser system. When we analysed the results obtained for mothers and their children no differences were found between polluted and control districts. The prolongation of alkali unwinding and electrophoresis did not increase sensitivity of the assay. No effects of prematurity, ethnicity, smoking or GSTM1 polymorphism were observed for any of the Comet parameters. Multiple regression analyses were performed for the European population (n = 285). A statistical model was fitted to determine the relationship between the Comet parameters of mothers and their children. According to our results it seems that the Comet assay was not a particularly sensitive technique to determine the effects of environmental pollution at the DNA level if peripheral WBC are used.

DNA adducts in human placenta as related to air pollution and to GSTM1 genotype.

DNA adducts in human placenta have been studied in relation to metabolic genotype for glutathione S-transferase M1 (GSTM1) in 98 mothers living in two regions with a different annual average air pollution levels: Northern Bohemia-the district of Teplice as polluted industrial area (mines, brown coal power plants) and Southern Bohemia-the district of Prachatice as agricultural area without heavy industry. Forty-nine placenta samples (25 from the Teplice district and 24 from the Prachatice district) from non-smoking mothers with the date of delivery in the summer period and 49 placenta samples (25 from the Teplice district and 24 from Prachatice district) from mothers with the date of delivery in the winter period were analysed. The total DNA adduct levels were calculated as the sum of adducts in the diagnoal radioactive zone (DRZ) and one distinct spot outside of the DRZ (termed X), which was detected in almost all placenta samples. We found total DNA adduct levels of 1.40 +/- 0.87 (0.04-3.65) and 1.04 +/- 0.63 (0.11-3.08) adducts per 10(8) nucleotides for the Teplice and Prachatice districts, respectively. The significant difference between both districts in placental DNA adduct levels was found for the winter sampling period only (1.49 vs. 0.96 adducts per 10(8) nucleotides; p = 0.023). No seasonal variation was observed for DNA adduct levels in the overall population studied. A positive GSTM1 genotype was detected in 51 subjects, while GSTM1-null genotype was found in 47 subjects. Higher DNA adduct levels were detected in a group with GSTM1-null genotype (p = 0.009). This finding seems more significant for subjects in the Teplice district (p = 0.047) than for those in the Prachatice district (p = 0.092). Significant district and seasonal differences were found in subgroups carrying the GSTM1-null genotype. DNA adduct levels in placentas of mothers with GSTM1-null genotype living in the polluted district of Teplice were higher than those in Prachatice (p = 0.050); also the adduct levels in placentas sampled in the summer period were higher than those sampled in the winter period (p = 0.011). Our results indicate that simultaneous analysis of DNA adducts and metabolic genotypes could emphasize the use of DNA adduct measurements, particularly in the case of the environmental exposure when the total doses of genotoxic pollutants are very low.

Influence of GSTM1 and NAT2 genotypes on placental DNA adducts in an environmentally exposed population.

The placenta bulky DNA adducts have been studied in relation to metabolic genotypes for glutathione S-transferase M1 (GSTM1) and N-acetyl transferase 2 (NAT2) in 158 mothers (113 nonsmokers and 45 smokers) living in two regions with different annual average air pollution levels of sulphur dioxide, nitrogen oxides, particulate matter < 10 microns, and polycyclic aromatic hydrocarbons. One region was the district of Teplice as the polluted industrial region with mines and brown coal power plants, and the other was the district of Prachatice, an agricultural region without heavy industry. DNA adduct levels were determined by using a butanol extraction enrichment procedure of 32P-postlabeling. GSTM1 and NAT2 genotypes were studied by using polymerase chain reaction. The total DNA adduct levels included a diagonal radioactive zone (DRZ) and one distinct spot outside DRZ (termed X), which was detected in almost all placenta samples and correlated with DRZ (r = .682; P < .001). We found the total DNA adduct levels 2.12 +/- 1.46 (0.04-7.70) and 1.48 +/- 1.09 (0.11-4.98) adducts per 10(8) nucleotides for Teplice and Prachatice districts, respectively, indicating significant differences between both regions studied (P = .004). Elevated DNA adduct levels were found in smoking mothers (10 or more cigarettes per day) by comparison with nonsmoking mothers (3.21 +/- 1.39 versus 1.32 +/- 0.88 adducts per 10(8) nucleotides; P < .001). Placental DNA adduct levels in smokers correlated with cotinine measured in plasma (r = .432; P = .003). This relation indicates that cigarette smoking could be predominantly responsible for DNA adduct formation in placentas of smoking mothers. DNA adduct levels were evaluated separately for non-smokers (1.50 +/- 1.00 vs. 1.09 +/- 0.66 adducts/10(8) nucleotides for the Teplice and Prachatice districts, respectively; P = .046) and smokers (3.35 +/- 1.47 vs. 2.91 +/- 1.20 adducts/10(8) nucleotides for Teplice and Prachatice districts, respectively; P = .384) to exclude the effect of active cigarette smoking on the district variation. These findings indicate that the effect of the environmental pollution in cigarette smokers is practically overlapped by tobacco exposure. No seasonal variation was observed for DNA adduct levels in the overall population studied and no relation between total DNA adduct levels in placenta and levels of vitamins A, C, and E in venous and cord blood was found. A positive GSTM1 genotype was detected in 78 subjects, while negative GSTM1 genotype was found in 80 subjects. Higher DNA adduct levels were detected in the group with GSTM1-negative genotype by comparison with GSTM1-positive genotype (2.05 +/- 1.30 vs. 1.66 +/- 1.39 adducts/10(8) nucleotides; P = .018). This finding is more pronounced in the Teplice district (2.33 +/- 1.36 vs. 1.88 +/- 1.56 adducts/10(8) nucleotides; P = .053) than for the Prachatice district (1.61 +/- 1.09 vs. 1.36 +/- 1.10 adducts/10(8) nucleotides; P = .248) and for nonsmokers (1.45 +/- 0.82 vs. 1.18 +/- 0.93 adducts/10(8) nucleotides; P = .029) more than for smokers (3.45 +/- 1.14 vs. 2.95 +/- 1.62 adducts/10(8) nucleotides; P = .085). Significant district and seasonal differences were found in subgroups with GSTM1-negative genotype. DNA adduct levels in placentas of the GSTM1-negative subgroup were higher in mothers living in the polluted district of Teplice than in Prachatice (P = .012). The adduct levels in placentas sampled in the summer period were higher than in the winter period in the GSTM1-negative population (P = .006). No effect of the NAT2 genotype on DNA adduct levels was observed.

Teplice program--the impact of air pollution on human health.

The aim of the Teplice Program is to investigate and assess the impact of air pollution on the health of the population in the district of Teplice, Czech Republic. Characterization of the air pollutants demonstrated unusually high concentrations during winter inversions of fine particles dominated by acidic sulfates, genotoxic organic compounds, and toxic trace elements. The major source of airborne fine particles is the burning of coal for heating and power. Human exposure and biomarker studies demonstrated large seasonal variations in air pollution within the Teplice District and higher seasonal average pollution levels than the comparative district, Prachatice. Personal exposures to fine particles and organic carcinogens [e.g., polycyclic aromatic hydrocarbons (PAH)] were correlated with excretion of PAH metabolites in urine, several trace metals in blood, and DNA adducts in white blood cells. Respiratory and neurobehavioral studies of school children were conducted using questionnaires and clinical measures. A significantly higher prevalence of adverse respiratory symptoms and decreased lung function were found in the Teplice district than in Prachatice. The neurobehavioral studies indicated significantly higher teacher referrals for clinical assessment in Teplice, but the majority of objective performance measures did not differ. Reproductive studies were conducted in both males and females. A study of the effects of exposure on pregnancy and birth found an excess prevalence of low birth weight and premature births in Teplice; these adverse effects were more common in infants conceived in the winter and whose mothers were smokers. Based on questionnaires and medical examination, the reproductive development of young men was not different between districts and seasons, however, measures of semen quality suggest that exposure to high levels of air pollution are associated with transient decrements in semen quality.

[The environment, life style and pregnancy outcome]. / Zivotní prostredí, zivotní styl a výsledky tehotenství.

BACKGROUND: Unproved statement is frequently suggested, that pregnancy outcome in mining districts of Northern Bohemia is damaged due to high level of pollution. The aim of study is to compare the pregnancy outcome of women from the mining district of Teplice (with extremely high air pollution) with that of Prachatice (district with relatively low pollution level) and to evaluate the relative impact of various factors (environmental exposure, lifestyle variables, individual exposures). In the preliminary communication the study design is described and first results are discussed. METHODS AND RESULTS: About 2260 pregnancies terminated by delivery in Teplice and Prachatice districts from April 1994 till June 1995 were enrolled. In the prospective cohort study all pregnancies terminated during 1994-1997 will be included. Data about reproduction and health history and lifestyle are obtained from questionnaires completed by mothers and medical staff. As indicators of reproductive damage low birth weight (< 2500 g) and premature birth (< 37th week) are used. Preliminary descriptive results obtained during first 14 months of data collection are discussed. Prevalence of low birth weight was 8.8% in the district of Teplice but only 4.0% in Prachatice (P < 0.001). It is 6.2% and 3.4% for prematurity (P < 0.01). However, 14.1% Gypsy births were found in Teplice whereas only 2.9% in Prachatice (P < 0.001). Prevalence of low birth weight is 23.6% and that of prematurity 13.4% among Gypsy births. Significant linear relationship of low birth weight (P < 0.0001) and prematurity (P < 0.0001) with number of cigarettes smoked by mother at early pregnancy was found. Significantly higher proportion of Teplice mothers smokes significantly more cigarettes (P < 0.0001). Relative risk of premature birth of infants conceived in winter by smoking mothers is 3.2 times higher for non-Gypsies (P < 0.0001) and 6.5 times higher by Gypsies (P < 0.0001). CONCLUSIONS: Differences of prevalence of low birth weights and prematurity between Teplice and Prachatice districts would be explained partly by differences in ethnic structure and smoking habits. However, the difference remains significant statistically just after exclusion of both factors mentioned. The adverse effect of the Winter conception period on the prematurity prevalence could be due to synergistic effect of smoking and environmental load (increased level of pollutants in winter period); simultaneous action of both factors may exceed the threshold of protective mechanisms.

Cytogenetic analysis of 1508 spontaneous abortions originating from south Slovakia.

Knowledge with regard to the spontaneous abortion cytogenetics has been derived exclusively from populations of the highly developed countries; its full applicability to east-european populations living in the peculiar conditions of the former 'socialist countries' may be questioned. The consecutive series of 1912 spontaneous abortion products with identifiable embryonal tissue was collected in six maternal clinics in south Slovakia. 1508 specimens were set in culture. Among 926 (61.4%) successfully karyotyped abortions, 46.0% were chromosomally abnormal specimens. The proportion of the groups of abnormalities is similar to that in other large series, with the exception of a higher proportion of mosaics (14.3% of the abnormalities). The abnormality rate in the whole sample also lies within the range of values published. However, significant inter-regional variability has been established: the chromosome abnormality rate in the urban subsample is 47.8%, whereas the value was only 35.3% for rural southern districts. The anomaly rates are lower for all maternal ages and gestation phases in the country subsample. The possibility of the environmental diversity effect was discussed. No other major peculiarity of cytogenetic abortion characteristics can be determined in the population studied.

The importance of prenatal period to the new-borns population quality.

Approximately 60% of all human pregnancies terminate spontaneously before birth, mostly before being recognized. Exceptionally high prevalence of abnormalities has been found in this reproduction output. Original frequency of chromosomal (ChA) and developmental anomalies (DA) is not known, but may be very high. From 100 spontaneously aborted fetuses about 50 are ChA, approximately 70 are DA and only about 20 are without any pathological finding. Using data on ChA and DA distribution in newborns and those in abortuses--together with the knowledge on abortion rates in various gestation phases--the prenatal population structure may be reconstructed: in the pregnancy recognition phase about 7% ChA and 10-15% DA conceptuses remain in the population of surviving fetuses. Prenatal selection decreases gradually the frequency of anomalies to the values that are usually found in new-borns. The disappearance of particular anomalies is nonrandom, changing the malformation spectrum continually. The risk of prenatal elimination of the anomaly is not invariably proportional to the degree of phenotype damage of the fetus. Study of the hidden part of prenatal population offers the possibility to cover a considerably larger fraction of the whole reproduction output and supplies new valuable knowledge.