High indoor microbial levels are associated with reduced Th1 cytokine secretion capacity in infancy

Background: Exposure to microbes and their components may affect the maturation of the immune system. We examined the association of house dust microbial content with cytokine-producing capacity at birth and at the age of 1 year. Methods: Production of TNF-α, IFN-γ, IL-5, IL-8 and IL-10 at birth (n = 228) and at the age of 1 year (n = 200) following 24- and 48-hour whole-blood stimulation with staphylococcal enterotoxin B (SEB), lipopolysaccharide and the combination of phorbol ester and ionomycin was measured. Concentrations of ergosterol (marker for fungal biomass), muramic acid (marker for Gram-positive bacteria) and 3-hydroxy fatty acids with a carbon chain length from 10 to 14 (marker for Gram-negative bacteria) in living room floor dust were analyzed using gas chromatography-tandem mass spectrometry. Five single microbial species or groups were determined using a quantitative polymerase chain reaction method. Results: A high total level of the studied Gram-positive bacteria in general or Mycobacterium spp. in house dust was associated with decreased SEB-stimulated IFN-γ production, especially at the age of 1 year. The total level of indoor fungi analyzed (Penicillium spp., Aspergillus spp. and Paecilomyces variotii group, Trichoderma viride/atroviride/koningii,Wallemia sebi) was also inversely associated with IFN-γ production at the age of 1 year, but this association did not remain significant after adjustment for potential confounders. A few associations were found between microbial exposures and other measured cytokines. Conclusions: High indoor microbial exposures may affect immune development in early life by reducing T helper type 1 cytokine secretion capacity. The observed hyporesponsiveness may reflect the adaptation of the immune system to environmental antigens. In future, more attention should be paid especially to the immunomodulatory role of exposures to Gram-positive bacteria.     

Odour annoyance and physical symptoms among residents living near waste treatment centres

Waste treatment processes produce odours and biological emissions to the environment, but their health effects are controversial. The aim of our study was to assess odour-associated self-reported physical symptoms among residents living near waste treatment centres. The study was conducted in the surroundings of five large-scale Finnish waste treatment centres with composting plants. In 2006, 1142 randomly selected residents living within 1.5, 3.0 and 5.0 km of these centres were interviewed by telephone. A questionnaire with 102 items asked about respondent's personal characteristics, odour exposure and symptoms during the preceding 12 months. Physical symptoms were analysed by distance to the waste treatment centre and by the respondent's perception and annoyance of waste treatment odour. The residents who were classified as “annoyed of the odour” reported following physical symptoms more than the others did: unusual shortness of breath (OR 1.5, 95% CI 1.0–2.2), eye irritation (1.5, 1.1–2.1), hoarseness/dry throat (1.5, 1.1–2.0), toothache (1.4, 1.0–2.1), unusual tiredness (1.5, 1.1–2.0), fever/shivering (1.7, 1.1–2.5), joint pain (1.5, 1.1–2.1) and muscular pain (1.5, 1.1–2.0). Moreover, the ORs for almost all other physical symptoms were elevated among the annoyed respondents. Reported odour annoyance near the waste treatment centres showed an association with many physical symptoms among residents living in the neighbouring areas.     

Identifying emerging trends in recreational drug use; outcomes from the Psychonaut Web Mapping Project

Background

This paper presents the outcomes of the 2-year European Union funded Psychonaut Web Mapping Project which aimed at developing and implementing an integrated web mapping system to promptly identify and learn about novel psychoactive substances (NPS; “legal highs”) through the regular monitoring of the Internet.

Methods

More than 200 discussion forums, social media, online shops, websites and other Internet resources (e.g. YouTube, eBay, Google, Google Insight) have been extensively and regularly monitored in 7 European countries (UK, Finland, Norway, Belgium, Germany, Italy and Spain) for emerging trends of NPS throughout the period of the study.

Results

Key online resources have been identified as “leading edge” which have provided accurate and timely information on novel emerging compounds. In total more than 400 substances/products have been recorded. NPS have been noted online before reaching wider audiences.

Discussion

Although a high number of novel psychoactive substances have been identified in the 2-year duration of the project, not all have become trends that needed public health response. Conversely, new recreational drug phenomena such as “spice drugs,” mephedrone and naphyrone were all identified as emerging trends in forums and websites. In addition, it has been possible for the first time to collate detailed information on these and several more compounds even though no or limited scientific publications were available. It is therefore recommended that these monitoring activities are to be continued, that more countries, researchers and health professionals are involved, and that the findings are widely shared with all the relevant agencies, health professionals and future research projects.Implications, advantages and limitations of using the Internet as primary source for identifying emerging trends are also discussed.     

Increased levels of lipid peroxides in aged rat brain as revealed by direct assay of peroxide values

Lipid peroxide concentrations in brain tissues of young and aged rats were determined by a direct method for measuring peroxide values. Three different brain regions were analyzed for lipid peroxides. The peroxide levels increased in all three regions of aged as compared to those of young rats, while lipid peroxides in plasma appeared to be stable along with age. Lipid peroxides in cerebrum and cerebellum increased 1.6-2.0 times in aged brains compared with young ones, and about 3-fold in the brain stem. Increased levels of lipid peroxides in aged brains seem not merely due to increased pools of precursor polyene fatty acids, but rather due to altered protection systems for lipid peroxidase formation.     

Detection of Chlamydia pneumoniae by colorimetric in situ hybridization

Chlamydia pneumoniae causes chronic infections, which have been associated with cardiovascular diseases. The antigenic structures of the organism have been detected in atherosclerotic lesions by immunohistochemistry. We wanted to further evaluate the presence and localization of C. pneumoniae in different tissues by in situ hybridization. We established a new colorimetric in situ hybridization method using a digoxigenin-labelled probe and studied the localization of C. pneumoniae in formalin-fixed, paraffin-embedded lungs of infected mice. We also used the method to study its presence in 12 abdominal aortic aneurysms. In C. pneumoniae-infected mice, the organism was first detected in bronchial epithelial cells, and later in pneumocytes and endothelial cells. C. pneumoniae was also present in five of eight abdominal aortic aneurysms previously shown to be positive by immunohistochemistry. The findings are in accordance with the invasive nature of C. pneumoniae, and confirm its presence in abdominal aortic aneurysms.     

Chlamydia pneumoniae reactive T lymphocytes in the walls of abdominal aortic aneurysms.

BACKGROUND: The presence of Chlamydia pneumoniae in the walls of abdominal aortic aneurysms (AAAs) has been demonstrated recently, but its role in the cause and/or maintenance of aortic wall inflammation is not known. In the present study, we have investigated the possible relationship between C. pneumoniae and the antigen specificity of T lymphocytes mediating inflammation in AAA tissue. MATERIALS AND METHODS: Tissue specimens were obtained from 22 consecutive AAA patients undergoing elective surgery (mean age 67 +/- 1 year). Immunohistochemical analysis of the formalin-fixed tissue was performed using the streptavidin-biotin-peroxidase method. In vivo activated T lymphocytes were propagated from the specimens with interleukin (IL) 2, and antigen specificity of the established T-cell lines was analysed in the presence of autologous antigen-presenting cells using radioactive thymidine labelling. RESULTS: Immunohistological staining of AAA tissue showed the presence of C. pneumoniae antigen in 55% (6/11) of the samples studied. The inflammatory cell infiltrate of the AAA tissue contained 60-90% T (CD45RO) and 0-10% B (CD20) cells. When the tissue specimens were cultured without antigen in the presence of IL-2, lymphocyte propagation was achieved in 17 out of the 22 samples. Chlamydia pneumoniae antigen was found to induce a positive proliferative response in 8 of the 17 lines. CONCLUSIONS: The presence of C. pneumoniae specific T lymphocytes among in vivo activated cells from the AAA tissue specimens suggests that C. pneumoniae participates in the maintenance of the inflammatory response in the tissue and may thus be involved in the progression of the disease.     

Monoclonal antibodies against oxidized low-density lipoprotein bind to apoptotic cells and inhibit their phagocytosis by elicited macrophages: Evidence that oxidation-specific epitopes mediate macrophage recognition

Apoptosis is recognized as important for normal cellular homeostasis in multicellular organisms. Although there have been great advances in our knowledge of the molecular events regulating apoptosis, much less is known about the receptors on phagocytes responsible for apoptotic cell recognition and phagocytosis or the ligands on apoptotic cells mediating such recognition. The observations that apoptotic cells are under increased oxidative stress and that oxidized low-density lipoprotein (OxLDL) competes with apoptotic cells for macrophage binding suggested the hypothesis that both OxLDL and apoptotic cells share oxidatively modified moieties on their surfaces that serve as ligands for macrophage recognition. To test this hypothesis, we used murine monoclonal autoantibodies that bind to oxidation-specific epitopes on OxLDL. In particular, antibodies EO6 and EO3 recognize oxidized phospholipids, including 1-palmitoyl 2-(5-oxovaleroyl) phosphatidylcholine (POVPC), and antibodies EO12 and EO14 recognize malondialdehyde-lysine, as in malondialdehyde-LDL. Using FACS analysis, we demonstrated that each of these EO antibodies bound to apoptotic cells but not to normal cells, whereas control IgM antibodies did not. Confocal microscopy demonstrated cell-surface expression of the oxidation-specific epitopes on apoptotic cells. Furthermore, each of these antibodies inhibited the phagocytosis of apoptotic cells by elicited peritoneal macrophages, as did OxLDL. In addition, an adduct of POVPC with BSA also effectively prevented phagocytosis. These data demonstrate that apoptotic cells express oxidation-specific epitopes-including oxidized phospholipids-on their cell surface, and that these serve as ligands for recognition and phagocytosis by elicited macrophages.