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Biomedical subjects

D Nowak

Publications and source records attributed to D Nowak.

At least 55 records · Page 3Linked to original sources

Farming exposure in childhood, exposure to markers of infections and the development of atopy in rural subjects.

BACKGROUND: Within the context of the hygiene hypothesis, we aimed to study the potential association between farming-related risk factors and Toxoplasma gondii (T. gondii) as well as Helicobacter pylori (H. pylori) seropositivity. METHODS: The study included questionnaire data and serum samples of 321 young adults living in a rural environment. Serum samples were analysed for specific IgE to a common panel of aeroallergens (SX1) as well as IgG against T. gondii and H. pylori. RESULTS: Regular contact with animal stables before the age of 3 years (odds ratio (OR) (95% confidence interval): 2.0 [1.0; 4.0]) and unpasteurized milk consumption at age 6 years (1.8 [1.0; 3.3]) were the strongest risk factors for T. gondii infection. None of the farming-related factors were significantly associated with H. pylori infection. Current consumption of raw farm milk was not significantly associated with H. pylori infection (2.1 [0.8; 5.3]). Regular contact with animal houses before the age of 7 years was the strongest predictor for atopy (0.49 [0.26-0.96]). The reduction in risk could not be further decreased by any other factor under consideration. After adjustment for animal house contact, the OR for atopy was decreased by raw milk consumption and H. pylori infection in an additive manner. CONCLUSION: Exposure to farming environments in childhood might predict T. gondii seropositivity in rural subjects. Nevertheless, the strongest predictor for atopy in rural subjects seems to be regular contact with farm animals. Whether T. gondii infection is an intermediate factor in the association between farm contact and atopy needs to be confirmed in larger studies.

Adult↗

Toxoplasma gondii infection, atopy and autoimmune disease.

While for many allergens a dose-response relationship has clearly been established the association between early childhood exposure to cat allergens and risk of sensitisation is still controversial and even inverse relations have been described. At the same time, a negative association between Toxoplasma gondii (T. gondii) infection and atopic diseases has been found in epidemiologic studies. As cats are the major source of T. gondii oocysts, we hypothesize that cat allergen exposure might be a confounder in the association between T. gondii infection and allergic diseases. Furthermore, it is well known that atopic diseases are T helper cell 2 (Th2) driven while autoimmune diseases are dominated by a Th1 response. A counterbalance between Th1 and Th2 cells has been postulated. However, it has been shown recently that subjects with autoimmune disease are more likely to suffer from atopic diseases. Therefore, similar cytokine profiles might underlie these disorders. If this holds true it can be hypothesised that T. gondii infection is associated with a lower prevalence of autoimmune disease.

Allergens↗

Elevated exhalation of hydrogen peroxide in patients with systemic sclerosis.

BACKGROUND: Systemic sclerosis is accompanied by an influx of activated phagocytes into distal airways. These cells release H2O2, which may evaporate from the airways surface and be detected in expired breath condensate. We tested whether patients with systemic sclerosis exhale more H2O2 than healthy subjects and whether breath condensate H2O2 levels correlate with some clinical parameters. MATERIAL AND METHODS: H2O2 was measured fluorimetrically in the expired breath condensate of 27 patients (22 women, five men, mean age 49 +/- 13.1 years) with systemic sclerosis and 27 age- and sex- matched healthy controls. RESULTS: Exhaled H2O2 levels were 3.5-fold higher (0.88 +/- 0.62 microM vs. 0.25 +/- 0.17 microM, P < 0.001) in the patients with systemic sclerosis than in the controls. Treatment with cyclophosphamide and/or prednisone (29 +/- 50 months, range 3-168 months) did not significantly decrease H2O2 exhalation (0.78 +/- 0.50 microM, n= 10 vs. 0.94 +/- 0.67 microM, n= 17, P > 0.05). No significant difference was found between patients with limited and diffuse scleroderma (1.03 +/- 0.69 microM, n= 17 vs. 0.63 +/- 0.41 microM, n= 10, P > 0.05). H2O2 levels correlated with disease duration (r = 0.38, P < 0.05) and time from the first Raynaud's episode (r = 0.44, P < 0.05). CONCLUSIONS: Patients with systemic sclerosis exhale more H2O2 than healthy controls, suggesting involvement of reactive oxygen species in disease processes. Lack of significant intergroups differences in H2O2 levels may have resulted from the small number of patients analyzed.

Breath Tests↗

Exhaled hydrogen peroxide correlates with the release of reactive oxygen species by blood phagocytes in healthy subjects.

Various cells including polymorphonuclear leukocytes, alveolar macrophages and type-II pneumocytes may be a source of exhaled hydrogen peroxide (H2O2) in airways of humans. H2O2 can convert into hydroxyl radicals leading to peroxidative damage of airways structures and formation of volatile thiobarbituric acid-reactive substances (TBARs). We tested whether exhalation of H2O2 and TBARs by healthy subjects depends on reactive oxygen species generation from blood phagocytes. The expired breath condensate (EBC) and blood specimens were collected from 41 healthy, never smoked subjects (mean age 20.7 +/- 0.8 years, 18 men, 23 women) and then the EBC concentration of H2O2 and TBARs and 2 x 10(-5) M fMLP-provoked whole blood chemiluminescence response was measured. The mean concentration of H2O2 and TBARs in EBC was 0.28 +/- 0.17 and 0.04 +/- 0.13 microM with ratio of positive readings reaching 36/41 and 4/41, respectively. The chemiluminescence response to n-formyl-methionyl-leveyl-phenylalanine stimulation was obtained in all cases and the following parameters were estimated: basal chemiluminescence (bCl); peak chemiluminescence (pCl); absolute light emission (aCl); and peaktime. H2O2 levels in EBC positively correlated (Spearmann test) with bCl (r=0.41, P<0.01), pCl (r=0.47, P<0.01), aCl (r=0.49, P<0.001), peaktime (r=0.52, P<0.001) in the whole group and with bCl (r=0.56, P<0.01), pCl (r=0.67, P<0.01), aCl (r=0.66, P<0.01) in men and with aCl (r=0.41, P<0.05) and peaktime (r=0.48, P<0.05) in women. No association between exhaled TBARs and blood phagocytes activity was found. These results indicate that H2O2 exhalation in healthy never smoked subjects depends on ability of blood phagocytes to generate reactive oxygen species.

Adult↗

[Respiratory diseases in European farmers. Part 1: Literature review].

Farming is still one of the most important economic sectors in the world. At the same time, a high prevalence of respiratory diseases in farmers is well known. Among these, allergic and non-allergic asthma, chronic bronchitis, hypersensitivity pneumonitis and organic dust toxic syndrome (ODTS) are of uppermost importance. Because of the large variety of agriculture across Europe exposure conditions and risk factors for airway diseases may vary largely. While exposure to organic dusts and irritants are most important in grain and animal production, workers in greenhouses are mainly exposed to pollen, fungi, as well as pesticides. Up to now, the knowledge about the prevalence of respiratory diseases in European farmers working in different agricultural sectors was limited. Furthermore, reliable data on farming characteristics as well as exposure patterns that might prone risk factors for respiratory diseases were missing. Therefore, the European Farmers' Project was initiated. The results of this study are given in the second part of this paper.

Agricultural Workers' Diseases↗

[Respiratory diseases in European farmers-II. Part of the European farmers' project].

BACKGROUND: The aim of the European Farmers' Project was to estimate the prevalence of respiratory diseases in farmers across Europe. Furthermore, risk factors for respiratory symptoms in different parts of agricultural production should be assessed. METHODS: In the first part of the study, 7496 farmers from four European countries answered a written questionaire. Of these, 229 were visited at their farms in the second part of the survey. On site, spirometry, allergy tests, as well exposure measurements were performed. RESULTS: Farmers with animal production had a significantly lower prevalence of allergic diseases than the general population. In contrast, the prevalence of chronic phlegm was higher in animal farmers. Organic dust toxic syndrome (ODTS) was a major predictor of chronic bronchitis. It was indicated that allergens found in the working environment could be transfered to the living environment of the farmer. Poor ventilation as well as high temperatures inside the animal buildings were shown to have a negative impact on respiratory symptoms and lung function parameters. CONCLUSION: Animal farmers are at high risk of chronic bronchitis. Intervention studies on the efficacy of different types of ventilation are now warranted. Furthermore, prospective studies on the associaton between ODTS and COPD should be done.

Adult↗

Cost of illness of atopic asthma and seasonal allergic rhinitis in Germany: 1-yr retrospective study.

The purpose of this study was to evaluate the cost of illness of moderate-to-severe atopic asthma and/or seasonal allergic rhinitis (SAR) in Germany from the perspective of third-party payers (TPP) and patients. Five-hundred patients (276 children/adolescents) with moderate-to-severe asthma and/or SAR were included in this cross-sectional study. Information was collected using a specific patient questionnaire and the abstraction of patient records. Overall, annual costs per patient increased with the severity of atopic asthma and if it was associated with SAR. The average annual cost of SAR was Euro1,089 per child/adolescent and Euro1,543 per adult. Annual costs of severe asthma plus SAR increased to Euro7,928 per child/adolescent and to Euro9,287 per adult. For TPPs, the main cost drivers were medication, hospitalisation, and rehabilitation. The most significant costs for patients were household modifications. For children/adolescents, 60-78% of the expenditures were direct costs, while in adults, 58% of expenditures were indirect costs. It was also observed that patients with moderate and severe asthma used inhaled corticosteroids less frequently than recommended by treatment guidelines. In summary, the total cost for patients increases with the severity of atopic asthma and/or seasonal allergic rhinitis and indirect costs represent a large proportion of the total cost.

Adolescent↗

Region-related risk factors for respiratory symptoms in European and Californian farmers.

The aim of this study was to determine the prevalences and regional risk factors for respiratory symptoms in European and Californian farmers. Farmers participating in the 1993-1997 surveys performed in Europe (n = 7,188) and California (n = 1,839) were included in this cross-sectional study. Respiratory symptoms and farming characteristics were assessed by questionnaire and risk factors associated with symptoms using logistic regression. The prevalences of rhinitis and asthma were lower in European (12.7% and 2.8%) than in Californian farmers (23.9% and 4.7%), but chronic bronchitis and toxic pneumonitis were more prevalent in Europe (10.7% and 12.2%) than in California (4.41% and 2.7%). Respiratory symptoms were associated with poultry and rabbit farming, flower growing and the cultivation of grain and oil plants. Working in Europe was a statistically significant risk factor for chronic bronchitis and toxic pneumonitis. Chronic bronchitis was related to toxic pneumonitis, work inside confinement buildings and greenhouses. Chronic bronchitis and toxic pneumonitis are highly prevalent among European farmers and are mainly attributable to indoor work.

Adult↗

Activity of type IV collagenases (MMP-2 and MMP-9) in primary pulmonary carcinomas: a quantitative analysis.

PURPOSE: Matrix metalloproteinases MMP-2 and MMP-9 are implicated in invasion and metastasis of malignant tumors. We investigated the expression and activation of MMP-2 and MMP-9 in lung cancer compared with normal lung parenchyma, and looked for a potential marker of malignancy. METHODS: Thirty-six pulmonary carcinomas and paired normal lung specimens were analyzed by gelatin zymography and computer-assisted image analysis for the expression of MMP-2 and MMP-9. RESULTS: We showed that expression of both type IV collagenases was remarkably higher in carcinoma samples than in lung parenchyma. The MMP-9 levels in lung cancer were over twofold higher than in normal lung tissues. The levels of latent and active forms of MMP-2 in lung cancer samples were, correspondingly, 3.8- and 17-fold higher than in lung parenchyma. The tumor/normal (T/N) ratios of MMP-2 were negatively correlated with the hemoglobin levels and erythrocytes number. CONCLUSIONS: A high level of the active form of MMP-2 in almost all of the carcinomas and the near lack of its activation in normal lung parenchyma shows that MMP-2 activation is associated with the malignant phenotype and may serve as a good marker of malignancy. The correlation between low hemoglobin level and T/N ratio of MMP-2 may indicate significance of MMP-2 for angiogenesis.

Aged↗

[Prevalence of weather sensitivity in Germany].

BACKGROUND AND OBJECTIVE: As epidemiological data on prevalence of weather-related health effects were lacking we conducted a weather sensitivity (WS) survey in Germany. SUBJECTS AND METHODS: A total of 1064 citizens (age > 16) representative of the population in Germany were interviewed in January 2001. RESULTS: The results show that 19.2% of the population believe that weather influences their health to a "high degree", 35.3% that weather has "some influence on their health". The highest prevalence of WS (high + some influence) is found in the age group of > 60 years, in 68% of the subjects. The highest frequencies of weather-related symptoms are reported for stormy weather (30%) and when it gets colder (29%). The most frequent symptoms reported by weather-sensitive subjects are headaches/migraine (61%), lethargy (47%), sleep disturbances (46%), fatigue (42%), joint pain (40%), irritation (31%), depression (27%), vertigo (26%), concentration problems (26%) and scar pain (23%). 32% of the weather-sensitive subjects have been incapable to do their regular work because of weather-related symptoms at least once last year, 22% even several times. Co-morbidity was significantly higher in weather-sensitive subjects. CONSEQUENCE: On the basis of these data we are planning studies on causal factors of weather-related health effects.

Absenteeism↗