Identification of patients with chronic obstructive pulmonary disease (COPD) by measurement of plasma biomarkers.

INTRODUCTION: Inflammation is an important constituent of the pathology of chronic obstructive pulmonary disease (COPD), leading to alveolar destruction and airway remodelling. OBJECTIVE: The aim of this study was to assess the difference in plasma biomarkers of inflammation between asymptomatic smokers and patients with COPD. METHODS: We used commercially available enzyme-linked immunosorbent assay kits to measure the plasma levels of tumour necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), monocyte chemotactic protein-1 (MCP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1) and tissue inhibitor of metalloproteinase-2 (TIMP-2) on two occasions with a 2-week interval in patients with COPD (n = 20), asymptomatic smokers (n = 10) and healthy lifelong non-smokers (n = 10). The participants were characterised clinically, physiologically and by quantitative computed tomography by measuring the relative area of emphysema below -910 Hounsfield units (RA-910). RESULTS: The results of the biomarker measurements on the two occasions were highly reproducible. Patients with COPD had significantly higher plasma levels of IL-8 (P = 0.004) and significantly lower levels of TIMP-1 (P = 0.02) than smokers and non-smokers. There was no statistically significant difference between the three groups in the level of TNF-alpha, MMP-9, MCP-1 and TIMP-2. The IL-8/TIMP-1 ratio correlated significantly with the degree of airway obstruction measured as forced expiratory volume in 1 second (FEV(1)) % predicted (r = -0.47, P < 0.01); with the diffusion capacity (r = -0.41, P < 0.01); and with the grade of emphysema measured as RA-910 (r = 0.39, P = 0.01). CONCLUSION: These findings suggest that the measurement of plasma biomarkers, such as IL-8/TIMP-1, may aid to discriminate patients with COPD from smokers at lower risk of developing COPD.

Design of a fast multileaf collimator for radiobiological optimized IMRT with scanned beams of photons, electrons, and light ions.

Intensity modulated radiation therapy is rapidly becoming the treatment of choice for most tumors with respect to minimizing damage to the normal tissues and maximizing tumor control. Today, intensity modulated beams are most commonly delivered using segmental multileaf collimation, although an increasing number of radiation therapy departments are employing dynamic multileaf collimation. The irradiation time using dynamic multileaf collimation depends strongly on the nature of the desired dose distribution, and it is difficult to reduce this time to less than the sum of the irradiation times for all individual peak heights using dynamic leaf collimation [Svensson et al., Phys. Med. Biol. 39, 37-61 (1994)]. Therefore, the intensity modulation will considerably increase the total treatment time. A more cost-effective procedure for rapid intensity modulation is using narrow scanned photon, electron, and light ion beams in combination with fast multileaf collimator penumbra trimming. With this approach, the irradiation time is largely independent of the complexity of the desired intensity distribution and, in the case of photon beams, may even be shorter than with uniform beams. The intensity modulation is achieved primarily by scanning of a narrow elementary photon pencil beam generated by directing a narrow well focused high energy electron beam onto a thin bremsstrahlung target. In the present study, the design of a fast low-weight multileaf collimator that is capable of further sharpening the penumbra at the edge of the elementary scanned beam has been simulated, in order to minimize the dose or radiation response of healthy tissues. In the case of photon beams, such a multileaf collimator can be placed relatively close to the bremsstrahlung target to minimize its size. It can also be flat and thin, i.e., only 15-25 mm thick in the direction of the beam with edges made of tungsten or preferably osmium to optimize the sharpening of the penumbra. The low height of the collimator will minimize edge scatter from glancing incidence. The major portions of the collimator leafs can then be made of steel or even aluminum, so that the total weight of the multileaf collimator will be as low as 10 kg, which may even allow high-speed collimation in real time in synchrony with organ movements. To demonstrate the efficiency of this collimator design in combination with pencil beam scanning, optimal radiobiological treatments of an advanced cervix cancer were simulated. Different geometrical collimator designs were tested for bremsstrahlung, electron, and light ion beams. With a 10 mm half-width elementary scanned photon beam and a steel collimator with tungsten edges, it was possible to make as effective treatments as obtained with intensity modulated beams of full resolution, i.e., here 5 mm resolution in the fluence map. In combination with narrow pencil beam scanning, such a collimator may provide ideal delivery of photons, electrons, or light ions for radiation therapy synchronized to breathing and other organ motions. These high-energy photon and light ion beams may allow three-dimensional in vivo verification of delivery and thereby clinical implementation of the BioArt approach using Biologically Optimized three-dimensional in vivo predictive Assay based adaptive Radiation Therapy [Brahme, Acta Oncol. 42, 123-126 (2003)].

Radiation transport calculations for 50 MV photon therapy beam using the Monte Carlo code GEANT4.

A new thin transmission target technique for fast dose delivery using narrow scanned photon beams has been developed. High-energy, 50-100 MeV, electron beams of low emittance incident on thin low-Z targets produce narrow and intense high-energy bremsstrahlung beams. However, electrons transmitted through the target are bent from the therapeutic beam by a purging magnet and have to be effectively absorbed in a dedicated electron collector. The electron-photon transport through a treatment head has been studied using the Monte Carlo simulation toolkit Geant4. The Geant4 electromagnetic physics processes have been compared with experimental data of radial dose profiles. The differences between calculated and measured radial dose distributions are approximately 2-10%. Preliminary investigations of the collector design have been carried out in order to minimise secondary electron and photon contamination of the therapeutic beam. The toolkit presented here is promising for further development of narrow photon beam therapy.

Evidence for a protein transported through the secretory pathway en route to the higher plant chloroplast.

In contrast to animal and fungal cells, green plant cells contain one or multiple chloroplasts, the organelle(s) in which photosynthetic reactions take place. Chloroplasts are believed to have originated from an endosymbiotic event and contain DNA that codes for some of their proteins. Most chloroplast proteins are encoded by the nuclear genome and imported with the help of sorting signals that are intrinsic parts of the polypeptides. Here, we show that a chloroplast-located protein in higher plants takes an alternative route through the secretory pathway, and becomes N-glycosylated before entering the chloroplast.

Health perceptions of local community works: network women describe how flows of energy and space of action generate health and ill health.

This paper presents a theoretical model on how flows of energy and space of action generate health and ill health in a local community work. Local community work was assessed through a case study of women's networks in a peripheral region of northern Sweden. The aim of the study was to analyse what participation in women's networks can mean for the members health perceptions. A purposeful selection of women's networks was made for the purpose of carrying out a qualitative follow-up study. Grounded theory was used to analyse the data and to generate a theoretical model. The meaning of participation in networks proved to be plural, as both health-deteriorating and health-promotive mechanisms were found. Two core categories "flows of energy" and "a space of action" as well as the four ancillary categories: social relations within the network; increased awareness of gender and power; becoming visible; and material prerequisites for networking were grounded in the data. We suggest that under certain circumstances local community work can be of crucial importance for health promotion.

Inhibition of lipopolysaccharide-mediated human monocyte activation, in vitro, by alpha1-antitrypsin.

alpha1-Antitrypsin (AAT) is a major circulating and tissue inhibitor of serine proteinases. As such AAT is thought to play an important role in limiting host tissue injury at sites of inflammation. There is now increasing evidence, however, that AAT may exhibit biological activity independent of its protease inhibitor function. In this study we compared the effects of native (inhibitory) and modified (non-inhibitory), e.g., polymerised and oxidised forms of AAT on LPS-induced human monocyte activation, in vitro. We found that native AAT inhibited LPS-stimulated synthesis and release of TNFalpha and IL-1beta mRNA and protein, respectively, but enhanced the release of the anti-inflammatory cytokine, IL-10. Similarly, polymerised and oxidised forms of AAT inhibited LPS-stimulated IL-1beta and TNFalpha. The effects of AATs were observed whether added prior to or following removal of LPS, suggesting that sequestration of agonist was unlikely to explain their biological effects. Furthermore, studies with neutralising antibodies indicated that generation of IL-10 was unlikely to be the mechanism responsible for the inhibitory effects of AATs. Thus, our data demonstrate for the first time that AAT exhibits anti-inflammatory activity in vitro that is unrelated to inhibition of serine proteases.

Natural allergen exposure does not diminish the sensitivity of cytokine production to glucocorticosteroids in blood cells of seasonal allergic asthma and rhinitis patients.

Glucocorticosteroid (GCS) inhibition of cytokine production is a major anti-inflammatory mechanism. However, increased production of pro-inflammatory cytokines during allergic airway inflammation has been proposed to reduce GCS effects. This study aimed to investigate whether allergic airway inflammation due to natural allergen exposure might decrease the sensitivity of granulocyte-macrophage colony-stimulating factor (GM-CSF) production to GCS in blood cells. Blood samples were collected from patients with seasonal allergic asthma (n = 10) and rhinitis (n = 8) and healthy subjects (n = 9), before, during, and after the birch pollen season. Whole blood cultures were stimulated with LPS (10 ng/ml) and treated with budesonide (10(-11)-10(-7) M) for 20 h. GM-CSF levels were analysed using immunoassay. Birch pollen exposure did not alter LPS-stimulated GM-CSF production, although disease symptoms and blood eosinophils increased in the patients. There were no significant differences in budesonide inhibition of GM-CSF production by blood cells of asthma and rhinitis patients compared with cells of healthy subjects before, during or after the birch pollen season and no change in response to allergen exposure. A concentration of 1 nM budesonide inhibited GM-CSF production by more than 50% at all time points. In conclusion, natural allergen exposure did not reduce the sensitivity of GM-CSF production to GCS inhibition in blood cells of seasonal allergic asthma and rhinitis patients.