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D Nowak

Publications and source records attributed to D Nowak.

At least 19 recordsLinked to original sources
PubMed2007

European dissemination of a web- and case-based learning system for occupational medicine: NetWoRM Europe.

OBJECTIVE: Occupation has a large impact on health in Europe. In order to prevent and recognize occupational diseases, medical students and physicians should know about the potentially causal relationship between profession and diseases as well as the basic legal aspects of occupational medicine (OM). However, the opportunity of bedside teaching, the students' most favoured way of teaching, is limited. METHODS: One possibility to complete and improve traditional training in OM is computer-oriented case-based learning. Using the authoring system "CASUS" (INSTRUCT AG) cases can be created and handled without knowledge in computer sciences. RESULTS: So far, 19 cases have been created and evaluated by students of German universities. Due to the great efforts arising from the creation of such multimedia cases it is desirable and cost-effective to use the existing cases at several medical universities. Therefore, the Net-based Training in Work-Related Medicine (NetWoRM) project shares cases on an international base. In February and April 2005, 13 case-authors from 12 centres were trained in the basics of case creation during a 3 week programme in Munich. The overall evaluation of the participants indicated that this way of teaching case creation is very efficient. Up to now, nine cases were translated into English and five into Spanish. First implementation of the cases in Spain and Finland showed a good acceptance by the students but more evaluation has still to be done. CONCLUSION: Based on these results we conclude that exchange of case-based e-learning in OM is feasible and rewarding on an international base.

Case-Control Studies↗
PubMed2006

Elevated exhalation of hydrogen peroxide and circulating IL-18 in patients with pulmonary tuberculosis.

Mycobacteria are the strong stimulators of respiratory burst, resulting in production of reactive oxygen species and nitrogen intermediates. The aim of our study was to assess the concentration of hydrogen peroxide (H(2)O(2)) in expired breath condensate (EBC) and the serum level of interleukin-18 (IL-18) in patients with active pulmonary tuberculosis (TB) before introduction of chemotherapy and after 2 months of treatment. Sixteen patients, current cigarette smokers, with advanced pulmonary TB were enrolled into the study. As a control served two groups: I group--16 asymptomatic cigarette smokers, II group--17 healthy never smoked subjects. The level of H(2)O(2) in EBC was significantly higher in patients with TB (1.3+/-0.7 microM) as compared to cigarette are healthy nonsmoker subjects (0.4+/-0.1 and 0.2+/-0.1 microM, respectively, P<0.05). Two months of treatment significantly decreased the level of H(2)O(2) exhalation in TB patients (0.5+/-0.3 microM) to the value that was not different from that in asymptomatic smokers but was still higher than in never smoked subjects. Serum concentration of IL-18 in TB patients was higher than that found in both control groups either before and after antituberculous treatment (P<0.05). Exhaled H(2)O(2) did not correlate with circulating IL-18 in TB patients before or after treatment. These results demonstrated the occurrence of oxidative stress in the airways of TB patients completely attenuating after 2 months of successful antituberculous treatment.

Adult↗
PubMed2006

Heart rate variability, hemostatic and acute inflammatory blood parameters in healthy adults after short-term exposure to welding fume.

The present study aimed to investigate, whether short-term experimental exposure to high levels of welding fumes would be capable of exerting acute effects in healthy subjects. Specifically, we assessed cardiovascular function in terms of heart rate variability (HRV) as well as the concentrations of inflammatory mediators and hemostatic proteins in blood as outcome measures. Twenty subjects without a history of airway and cardiovascular diseases were exposed to either control air or welding fume for 1 h on 2 separate days under standardized conditions. The median concentration of the alveolar particle fraction during welding was 3.5 mg/m(3 )(quartiles: 1.4-6.3 mg/m(3); range 1.0-25.3 mg/m(3)). Five hours later a panel of clinical assessments was performed, including HRV measurement and drawing of blood samples. There were no changes in symptom ratings or lung function after welding fume exposure. Exposures did also not differ regarding effects on time- and frequency-domain parameters of HRV. Similarly, blood leukocyte numbers, cell differentials and the blood levels of fibrinogen, C-reactive protein, antithrombin III, factor VIII, von Willebrand factor, ristocetin cofactor, sICAM-1, tumor necrosis factor alpha, interleukin 6, interleukin 8 and epithelial neutrophil activating peptide 78 were not altered by welding fume inhalation. However, there was a significant fall in the level of endothelin-1 (P < 0.01). In conclusion, the data did not indicate effects of clinical significance of a short-term high-level exposure to welding fumes on HRV or a set of blood hemostatic and acute inflammatory parameters in healthy subjects. The small but statistically significant effect on endothelin levels demonstrated that measurable effects could be elicited even in these individuals. Overall, welding fumes are not likely to exert acute cardiovascular effects in healthy individuals.

Adult↗
PubMed2006

Needlestick injuries during medical training.

Medical students are at risk of acquiring infections caused by needlestick injuries, although it is unknown when needlestick injuries are most likely to occur during medical training. The aim of this study was to define high-risk periods over the course of medical training. A cross-sectional study was conducted among medical students in the first, third, fourth and fifth years of training at two medical schools in Munich. Overall, 1317 (85%) students returned a questionnaire on demographic data, vaccination status against hepatitis B, lifetime prevalence of needlestick injuries, level of knowledge about measures after such accidents, and transmission risks. Lifetime prevalence of needlestick injuries was 23%, ranging from 12% in first year students to 41% in fourth year students. These accidents happened most commonly during medical internships, especially during blood-taking practices; an activity that usually starts during the third year of training. The frequency of respondents not vaccinated against hepatitis B also varied between first (21%) and fourth (6.6%) year students. Needlestick injuries occur frequently and early on in medical training. In order to decrease the risk of preventable infections, complete coverage of vaccination against hepatitis B should be achieved early in medical training.

Adult↗
PubMed2006

Smoking and the incidence of asthma during adolescence: results of a large cohort study in Germany.

BACKGROUND: The association between smoking and asthma or wheeze has been extensively studied in cross sectional studies, but evidence from large prospective cohort studies on the incidence of asthma during adolescence is scarce. METHODS: We report data from a cohort study in two German cities, Dresden and Munich. The study population (n = 2936) was first studied in 1995/6 at age 9-11 years as part of phase II of the International Study of Asthma and Allergies in Childhood (ISAAC II) and followed up in 2002/3. At baseline the parents completed a questionnaire and children underwent clinical examination and blood sampling. At follow up the young adults completed questionnaires on respiratory health, living, and exposure conditions. Incidence risk ratios (IRR) were calculated and adjusted for potential confounders using a modified Poisson regression approach. RESULTS: The adjusted IRR for incident wheeze for active smokers compared with non-smokers was 2.30 (95% confidence interval (CI) 1.88 to 2.82). The adjusted IRR was slightly higher for incident wheeze without a cold (2.76, 95% CI 1.99 to 3.84) and the incidence of diagnosed asthma (2.56, 95% CI 1.55 to 4.21). Analysis of duration and intensity of active smoking indicated dose dependent associations. Stratified analyses showed that the risk of incident wheeze without a cold in atopic smokers increased with decreasing plasma alpha(1)-antitrypsin levels at baseline (1.64, 95% CI 1.22 to 2.20 per interquartile range). CONCLUSIONS: Active smoking is an important risk factor for the incidence of asthma during adolescence. Relatively lower plasma levels of alpha(1)-antitrypsin, although well above currently accepted thresholds, may increase susceptibility to respiratory disease among atopic smokers.

Adolescent↗
PubMed2006

[Acute effects on the health of children after accidental exposure to epichlorohydrine].

PURPOSE: In September 2002, two freight trains collided at Bad Muender, Germany. The inhabitants were potentially exposed to combustion products and to the human carcinogen epichlorohydrine (ECH). We aimed to describe the geographical distribution of and potential risk factors for acute symptoms among children residing in Bad Muender. METHODS: The parents of a random sample of children were invited to answer a mail-in questionnaire (response rate 63%). The main outcome measures were self-reported acute symptoms potentially associated with combustion products (e. g., irritation of the eyes, nose, or throat) and stress-related unspecific symptoms (e. g., gastrointestinal complaints, sleep problems, headaches). The main location during the first 26 hours after the train accident served as exposure proxy measure. In addition, potential predictors for the symptoms under study were assessed. RESULTS: The prevalence of symptoms associated with combustion products was 5.9%. Unspecific symptoms were reported for 6.3% of the children. Main location and prevalence of symptoms were not significantly associated. Physician-diagnosed asthma and nasal allergies were the main predictors of symptoms. CONCLUSION: The prevalence of acute symptoms was relatively high in a random sample of children living close to the incident. However, associations between exposure to the accident and symptoms could not be established conclusively.

Accidents↗
PubMed2006

Inverse association between farm animal contact and respiratory allergies in adulthood: protection, underreporting or selection?

BACKGROUND: It has been argued that the inverse association between exposure to farm animals and nasal allergies observed in children and adults might be because of self-selection. AIMS: We aimed to assess the health-based selection out of farming in adults. MATERIAL AND METHODS: A cross-sectional study was carried out in a rural region. Overall, 4053 inhabitants (63%) aged 18-44 years responded to a questionnaire on respiratory diseases, life-time exposure to farming environments and potential confounders. For 2678 of these, specific immunoglobulin E to common allergens was available. The outcome was: (i) sensitization and symptoms of nasal allergies (symptomatic sensitization); (ii) sensitization without symptoms of nasal allergies (asymptomatic sensitization). RESULTS: Farm animal contact in childhood was associated with a decreased risk of symptomatic and asymptomatic sensitization. Continued exposure to farm animals in adulthood further decreased the odds ratio of symptomatic (odds ratio 0.2; 95% confidence interval 0.1, 0.4) but not asymptomatic sensitization (0.7; 0.4, 1.1). Starting farm animal contact in adulthood even increased the odds ratio of asymptomatic sensitization (2.4; 1.1, 5.2). CONCLUSIONS: The preventive effect of childhood contact to farm animals against sensitization continues into adulthood. However, in adulthood self-selection based on symptoms and underreporting of symptoms might also play a role.

Adolescent↗
PubMed2006

The role of parasitic infections in atopic diseases in rural schoolchildren.

BACKGROUND: There is increasing evidence that the farming environment has a protective effect as regards allergic diseases. Exposure to animal parasites, particularly helminth infections, is common in the farming environment. However, the role of helminths in this environment is not well determined to date. METHODS: This analysis focuses on 613 children 6-13 years of age from rural areas of Austria, Germany and Switzerland, who took part in the Allergy and Endotoxin (ALEX) study. Allergic diseases and farming characteristics were assessed by a standardized questionnaire and as a crude measure of possible exposure to helminths, IgG antibodies to Ascaris lumbricoides were measured. RESULTS: Exposure to nematodes, as determined by the levels of antibody to A. lumbricoides, was more frequent among farmers' children than non-farmers' children (39.8%vs 31.1%, P = 0.03). This positive serology was found to be significantly associated with high total IgE levels [odds ratio (OR) = 3.05, 95% confidence interval (CI) = 1.81-5.12] and eosinophilia (OR = 2.84, 95% CI = 1.66-4.84). However, no association between anti-nematode serology and the prevalences of asthma, wheeze, hay fever or atopy was found. A weak association for atopy was observed after adjustment for total IgE. CONCLUSION: Immunoglobulin G antibodies to A. lumbricoides, as a crude measure of possible exposure to helminths, did not indicate any protective effect against allergic diseases in this population. Although farmers' children had increased antibody levels reactive to helminth parasites indicating exposure, this did not explain the protective effect of farming against atopic diseases.

Adolescent↗
PubMed2006

Association between exposure to farming, allergies and genetic variation in CARD4/NOD1.

BACKGROUND: Caspase recruitment domain protein (CARD) 4 has been recently identified as an intracellular pattern recognition receptor that interacts with muropeptides found in common Gram-negative bacteria. We therefore aimed to explore whether the previously observed inverse association between exposure to microbial products and asthma and allergies in childhood is modified by genetic variation in CARD4. METHODS: We genotyped 668 children [mean age 9.3 (SD 1.5) years] enrolled in the cross-sectional ALEX study for seven haplotype tagging single nucleotide polymorphisms in CARD4. We studied the association of asthma, hay fever and allergen-specific serum immunoglobulin E with exposure to a farming environment and with levels of endotoxin and muramic acid measured in house dust samples. We tested whether these associations differed between the genotypes of the polymorphisms under study. RESULTS: A strong protective effect of a farming environment on allergies was only found in children homozygous for the T allele in CARD4/-21596, but not in children carrying the minor allele (C). Among the former, farmers' children had a significantly lower frequency of sensitization against pollen (5.8%), hay fever (1.7%) and atopic asthma symptoms (1.7%) compared with children not living on a farm (19.4%, 13.0% and 7.6%, P<0.01, <0.01 and <0.05, respectively). Conversely, no significant difference in prevalence of these phenotypes by farming status was found among children with a C allele in CARD4/-21596 (14.3%, 7.1% and 8.0%vs 16.5%, 9.0% and 5.7%, respectively). CONCLUSION: Polymorphisms in CARD4 significantly modify the protective effect of exposure to a farming environment.

Agriculture↗
PubMed2006

Do respiratory symptoms predict job choices in teenagers?

Existing guidelines advise adolescents with asthma and allergies against high-risk occupations. The aim of the current authors' analyses was to investigate the resulting self-selection in a prospective cohort study. The participants of Phase II of the International Study of Asthma and Allergies in Childhood in Germany (aged 9-11 yrs at baseline) were re-contacted after 7 yrs (response rate was 77%) and were asked to complete a questionnaire, which included items on atopic diseases. The subjects were also asked about the type of job they would like to have in the future (preferred job choice). Exposure to agents with potential asthma risk was evaluated using a job exposure matrix. The analyses were restricted to those in school-based vocational training programmes without occupational exposures. A total of 33% of subjects chose jobs with high asthma risk, 23% selected low asthma risk jobs and the remaining adolescents indicated jobs without known asthma risk (reference category). There were no statistically significant associations between asthma, allergic rhinitis or atopic dermatitis and selecting jobs with asthma risk. Participants with allergic rhinitis tended to select high risk jobs less frequently. In conclusion, self-selection into low risk jobs seems to play a minor role in teenagers with asthma or allergies.

Adolescent↗
PubMed2006

Differential effect of cigarette smoking on hydrogen peroxide and thiobarbituric acid reactive substances exhaled in patients with community acquired pneumonia.

BACKGROUND: This study was designed to investigate the effect of cigarette smoking on hydrogen peroxide (H2O2) and thiobarbituric reactive substances (TBARs) concentrations in exhaled breath condensate (EBC) in patients with community acquired pneumonia (CAP). METHODS: H2O2 and TBARs concentrations in EBC were determined with spectrofluorimetrical assays. RESULTS: Non-smoking CAP patients (n = 24) exhaled 1.4, 1.8 and 1.7 times more H2O2 than the smoking patients with CAP (n = 19) as assessed one (0.73 +/- 0.32 microM v. 0.51 +/- 0.36 microM), three (0.84 +/- 0.31 microM v. 0.47 +/- 0.24 microM) and five (0.66 +/- 0.28 microM v. 0.40 +/- 0.35 microM) days after admission (p < 0.05 in each case). Over 10 days of hospital treatment, mean level of exhaled H2O2 0.45 +/- 0.22 microM in CAP patients with smoking history was decreased if compared with 0.71 +/- 0.19 microM exhaled H2O2 in CAP group (p = 0.005). On the contrary, TBARs concentration evaluated over entire study period was increased in smoking CAP patients (median 0.02 microM, range 0-0.32 microM) compared with non-smoking group (median 0.01 microM, range 0-0.21 microM, p < 0.05). Concurrent, active smoking status was related with the decreased levels of H2O2 exhaled in breath condensate within the course of CAP but it appeared to increase levels of TBARs. CONCLUSIONS: The differential alternations of oxidative parameters in EBC with respect to the smoking status might provide evidence of increased H2O2 decomposition and enhanced generation of reactive species in airways of CAP patients.

Aged↗
PubMed2006

Moderate exercise decreases nitric oxide exhalation in patients with stable coronary artery disease.

Nitric oxide (NO) is present in exhaled air in humans and its level may decrease in heart diseases. Nitrates are metabolised to NO. In the present study we prospectively investigated how coronary disease treated with oral nitrates and physical exercise influence the exhaled NO concentration (exNO). The study was performed in 44 patients with stable coronary artery disease (CAD) treated with oral nitrates (31 nonsmokers and 13 smokers). End-tidal concentration of exhaled NO was measured by the use of a chemiluminescence method. The Bruce protocol of an exercise test was performed in 21 coronary patients and 11 volunteers. NO was measured before and 2-5 min after the test. We found no significant differences in the exNO level between healthy controls and CAD patients as analyzed either for the whole groups or non-smoker and smoker subgroups (6.01 parts per billion (ppb) vs. 4.91 ppb; 7.02 ppb vs. 5,89 ppb; 3.62 ppb vs. 3.33 ppb, respectively). However, the coronary patients group, as a whole, had lower exNO after exercise (4.22 ppb vs. 3,84 ppb, P<0.01). The difference persisted after division of this group into non-smokers and smokers; 5.19 ppb vs. 4,79 ppb, P<0.05 and 3.63 ppb vs. 3.27 ppb, P<0.05, respectively). The level of exNO changed inappreciably after exercise in control subjects. We conclude that coronary disease and oral nitrates, in themselves, do not influence the exhaled NO concentration. Physical exercise, on the other side, lowers the exhaled NO level in coronary patients.

Breath Tests↗
PubMed2006

Actin cytoskeleton and beta-actin expression in correlation with higher invasiveness of selected hepatoma Morris 5123 cells.

Our studies were focused on the isolation and characterization of highly motile fraction of cells from hepatoma Morris 5123 population. Cells that underwent several migration cycles through Matrigel - coated filters were successfully cultured. The invasion index was determined by means of Matrigel invasion assay. Statically significant increase in the value of invasion factor for selected cells variant in comparison to the parental population was observed. The considerable changes in the cell shape were followed by the reorganization of the actin cytoskeleton structure including a dense subcortical congestion in the distribution of beta -actin isoform. The visualization of this protein in tumor cells was performed by immunostaining and scanning fluorescent confocal microscopy. The results were confirmed by densitometry analysis of Western blots. In addition, the increased state of actin polymerization in the cytoplasmic fraction of selected cells was determined as measured by filamentous to monomeric (F:G) actin ratio. Concluding, the selected fraction of hepatoma Morris 5123 cells with higher invasion capacity was characterized by rounded shape, remarkable increase of beta -actin level, its submembrane concentration as well as with the increased state of actin polymerization with respect to parental cells population.

Actins↗
PubMed2005

Inhalation of stable dust extract prevents allergen induced airway inflammation and hyperresponsiveness.

BACKGROUND: Recent epidemiological studies have shown that growing up on a traditional farm provides protection from the development of allergic disorders such as hay fever and allergic asthma. We present experimental evidence that substances providing protection from the development of allergic diseases can be extracted from dust collected in stables of animal farms. METHODS: Stable dust was collected from 30 randomly selected farms located in rural regions of the Alps (Austria, Germany and Switzerland). The dust was homogenised with glass beads and extracted with physiological sodium chloride solution. This extract was used to modulate immune response in a well established mouse model of allergic asthma. RESULTS: Treatment of mice by inhalation of stable dust extract during sensitisation to ovalbumin inhibited the development of airway hyperresponsiveness and airway eosinophilia upon challenge, as well as the production of interleukin 5 by splenocytes and of antigen specific IgG(1) and IgE. Dust extract also suppressed the generation of human dendritic cells in vitro. The biological activity of the dust extract was not exclusively mediated by lipopolysaccharide. CONCLUSIONS: Stable dust from animal farms contains strong immune modulating substances. These substances can interfere with the development of both cellular and humoral immunity against allergens, thus suppressing allergen sensitisation, airway inflammation, and airway hyperresponsiveness in a murine model of allergic asthma.

Allergens↗