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1.
Yngve Kvinnsland Trond Stokke Ellen Aurlien 《Journal of nuclear medicine》2007,48(2):327; author reply 327-327; author reply 328
2.
Myeloperoxidase in human lung lavage 总被引:2,自引:0,他引:2
Birgitta Schmekel Yngve Hörnblad Margareta Linden Christer Sundström Per Venge 《Inflammation》1990,14(4):455-461
Bronchial wash and bronchoalveolar lavage were performed in 12 healthy subjects (five smokers), in order to elucidate whether or not material of neutrophil origin may be phagocytized by lung macrophages in vivo. Cells from different levels in the bronchial tree were obtained by sequential injection and subsequent aspiration of either four 50-ml or five 10-ml aliquots. Each aliquot was used for the determination of total and differential cell counts. The proportion of myeloperoxidase-positive alveolar macrophages was determined by specific immune histochemical staining. The percentage of myeloperoxidase-positive macrophages was highest (median 94.8%, range 37-98.5%) in the 10-ml aliquots and lowest in the last three 50-ml aliquots (median values 1-2.5%) (P less than 0.001). A significant correlation was obtained between the fraction of myeloperoxidase-positive macrophages and the percentage count of bronchoalveolar lavage neutrophils (r = 0.466, P less than 0.05). Furthermore, the cellular myeloperoxidase showed a significant inverse correlation (r = -0.46, P less than 0.05) to the viability of the bronchoalveolar lavage cells. Our findings are compatible with previous demonstrations in animals of neutrophil phagocytosis by lung macrophages and show that this phenomenon in particular occurs in the more proximal airways. The internalization of neutrophils or neutrophil components by airway macrophages may be an important scavenger mechanism for protection of the lung from the deleterious effects of activated neutrophils. 相似文献
3.
Gehad E. B. Elghazali Staffan Paulie Gudrun Andersson Yngve Hansson Gran Holmquist Jia-Bin Sun Tomas Olsson Hans Peter Ekre Marita Troye-Blomberg 《European journal of immunology》1993,23(11):2740-2745
The enzyme-linked immunospot (ELISPOT) assay has been proven to be an efficient and sensitive method for the enumeration of single cells secreting antibodies or cytokines. Here we have used this method to determine the number of interleukin-4 (IL-4)- and interferon-γ (IFN-γ)-producing cells in in vitro secondary responses to tetanus toxoid (TT) and the mycobacterial antigen (purified protein derivative; PPD) or the mitogen phytohemagglutinin (PHA). PHA-induced IL-4 and IFN-γ secretion was well correlated suggesting polyclonal activation of cells. This was not the case with the specific antigens, where PPD preferentially induced IFN-γ- and very few IL-4-producing cells, while TT-induced both IL-4 and IFN-γ. These differences are probably a reflection of the types of immunity the two antigens induce, mycobacteria preferentially inducing a cell-mediated T helper type 1 (Th 1) type of immunity, while immunity to tetanus is an antibody-dependent, Th 2 type of response. In individuals recently boosted with TT, a significant increase in both IL-4- and IFN-γ-producing cells in response to TT was seen at day 7 after boost, followed by decline. This was in contrast to what was seen in response to PPD where an increase of IFN-γ-producing cells after the TT boost at day 7 persisted for at least 14 days. These results suggest that after an in vivo boost both antigen-specific and nonspecific T cells are activated and that antigen-specific cells home to other organs and therefore may be difficult to demonstrate in the circulation. Our data show that the ELISPOT assay is a powerful tool for determining the frequency of cells secreting cytokines. The assay has several advantages over other assays since it is sensitive, measures the number of actually secreting cells, and avoids the problems of binding of cytokines to their cell-bound or soluble receptors. 相似文献
4.
Calculations of normal tissue complication probability (NTCP) values for the rectum are difficult because it is a hollow, non-rigid, organ. Finding the true cumulative dose distribution for a number of treatment fractions requires a CT scan before each treatment fraction. This is labour intensive, and several surrogate distributions have therefore been suggested, such as dose wall histograms, dose surface histograms and histograms for the solid rectum, with and without margins. In this study, a Monte Carlo method is used to investigate the relationships between the cumulative dose distributions based on all treatment fractions and the above-mentioned histograms that are based on one CT scan only, in terms of equivalent uniform dose. Furthermore, the effect of a specific choice of histogram on estimates of the volume parameter of the probit NTCP model was investigated. It was found that the solid rectum and the rectum wall histograms (without margins) gave equivalent uniform doses with an expected value close to the values calculated from the cumulative dose distributions in the rectum wall. With the number of patients available in this study the standard deviations of the estimates of the volume parameter were large, and it was not possible to decide which volume gave the best estimates of the volume parameter, but there were distinct differences in the mean values of the values obtained. 相似文献
5.
The brain is an important site of hematogenous metastases from malignanttumors in other organs. The effects on the brain is a combination of tissuedestruction induced by invading tumor cells and reactive alterationsoccurring around the metastases. This review focuses on neuropathologicalchanges around hematogenous metastases of the human brain. The peritumoralbrain parenchyma shows structural and functional changes of theintracerebral microvessels and edema. The endothelial cells of peritumoralmicrovessels express glucose transporter protein (GLUT 1) in the same way asthe normal brain. Reduction in immunostaining to GLUT 1 may occur in themicrovessels located within the metastases. This would indicateabnormalities of the blood-brain barrier in tumor vessels but normal barrierfunction in the peritumoral region. Reactive astrocytes and activatedmicroglial cells are both involved in the process of peritumoral gliosis.Activated glial cells produce numerous biological active compounds includingendothelin-1 which after release from such cells can influence the structureand function of the peritumoral brain tissue. Lesions of oligodendrocytesand edema may be implicated in myelin degeneration. Finally, metastases willinduce axonal and neuronal injuries as indicated by a recent study onexpression of -amyloid precursor protein (APP) in reactive axonalswellings. 相似文献
6.
Knut-Inge Klepp Carmen Perez Rodrigo Inga Thorsdottir Pernille Due Maria Daniel Vaz de Almeida Ibrahim Elmadfa Alexandra Wolf Jóhanna Haraldsdóttir Johannes Brug Michael Sjöström Agneta Yngve Ilse De Bourdeaudhuij 《Zeitschrift fur Gesundheitswissenschaften》2005,13(2):97-101
Aim The Pro Children consortium consists of the following partners: Knut-Inge Klepp (Coordinator), Department of Nutrition, University of Oslo, Norway; Carmen Perez Rodrigo, Unidad de Nutricion Comunitaria, Bilbao, Spain; Inga Thorsdottir, Unit for Nutrition Research, Landspitali University Hospital, Reykjavik, Iceland; Pernille Due, Department of Social Medicine, University of Copenhagen, Denmark; Maria Daniel Vaz de Almeida, Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto, Portugal; Ibrahim Elmadfa and Alexandra Wolf, Institute of Nutrition, University of Vienna, Austria; Jóhanna Haraldsdóttir, Research Department of Human Nutrition, Royal Veterinary and Agricultural University, Copenhagen, Denmark; Johannes Brug, Erasmus Medical Center Rotterdam, Department of Public Health, The Netherlands; Michael Sjöström and Agneta Yngve, Unit for Preventive Nutrition, Karolinska Institutet, Stockholm, Sweden; Ilse De Bourdeaudhuij, Department of Movement and Sport Sciences, Ghent University, Belgium.The Pro Children study is designed to assess vegetable and fruit consumption and determinants of the consumption patterns among European school children and their parents. A second objective is to develop and test strategies for promoting increased consumption of vegetables and fruits among school children and their parents.Subjects and methods Surveys of national, representative samples of 11-year-old school children and their parents were conducted in nine countries during October–November 2003, i.e. in Austria, Belgium, Denmark, Iceland, The Netherlands, Norway, Portugal, Spain and Sweden. Comprehensive school-based educational programmes were developed and tested in three settings, i.e. in the Bilbao region, Spain, in Rotterdam, The Netherlands, and in Buskerud county of Norway. A 24-h recall format and frequency items assessing regular intake were used to assess vegetable and fruit consumption. Determinants were assessed employing the theoretical framework of the ASE model (Attitudes, Social Influences and Self-Efficacy), including cognitive factors, normative influences, skills and environmental barriers related to vegetable and fruit consumption. The intervention programmes were tested employing a group-randomized trial design where schools were randomly allocated to an intervention arm and a delayed intervention arm. Surveys among all participating children and their parents were conducted prior to the initiation of the intervention (September 2003; month 0), immediately after the end of the intervention (at month 8) and at the end of the subsequent school year (month 20).Results Preliminary data from the project indicate that girls eat vegetables and fruit significantly more often than do boys across all participating countries. There are no sex differences, however, with respect to perceived availability of vegetables and fruit at home and outside the home setting. In all countries, perceived availability appears to be significantly associated with reported frequency of both vegetable and fruit consumption.Conclusion Experience so far indicates that the Pro Children Project will succeed in producing valid and reliable research instruments for assessing vegetable and fruit consumption among school children and their parents and that comparable, comprehensive intervention programmes can be implemented across geographic and cultural settings within Europe. 相似文献
7.
8.
Ludvig Paul Muren Asa Karlsdottir Yngve Kvinnsland Tore Wentzel-Larsen Olav Dahl 《Radiotherapy and oncology》2005,75(3):293-302
BACKGROUND AND PURPOSE: To study the impact of the new ICRU 62 'Planning organ at Risk Volume' (PRV) concept on the relationship between rectum dose-volume histogram (DVH) data and toxicity. PATIENTS AND METHODS: The acute gastro-intestinal (GI) RTOG toxicity in 127 prostate cancer patients prescribed a total dose of 70 Gy with conformal irradiation to either the prostate, the prostate and seminal vesicles or the whole pelvis (initial 50 Gy only) were analysed. DVHs were derived for the rectum only and for rectum extended with six PRV margin sets (narrow/intermediate/wide; anterior/anterior and posterior). The data was analysed using permutation tests, logistic regression and effective uniform dose (EUD) calculations. RESULTS: Acute Grade 2 GI toxicity was seen in 22 of 127 cases (17%). Permutation tests showed that the difference between DVHs for patients with and without Grade 2 effects was significant, both for rectum only and rectum PRVs (P-value range: 0.02-0.04), with generally lower P-values for the PRVs. In the logistic regression, the fractional DVH variables (i.e. volumes) were significantly related to toxicity, with approximately 2-3 times as many significant dose levels for the PRVs as for rectum only. E.g. with wide anterior and posterior margins (16 and 11 mm, respectively) the relation was significant at 26 different dose levels (6-7, 13-14, 35-43, 60-71 and 73 Gy), compared to nine levels (38-40, 43-44 and 71-74 Gy) for rectum only. EUDs were significantly different for patients with and without Grade 2 effects both for rectum only and the PRVs (95% confidence interval for EUD increase with Grade 2 effects: 0.1-3.1 Gy). CONCLUSIONS: All statistical methods applied indicated a small, but definite difference in DVH parameters between patients with versus those without Grade 2 effects. The difference was most pronounced when margins of 16 mm anterior and 11 mm posterior were applied. 相似文献
9.
Anne Stuedal Inger Torhild Gram Yngve Bremnes Herman Adlercreutz Marit B Veier?d Giske Ursin 《Cancer epidemiology, biomarkers & prevention》2005,14(9):2154-2159
AIMS: Certain phytoestrogens, such as lignans, may protect against developing breast cancer. Enterolactone is a lignan metabolite produced by the intestinal flora from dietary precursors such as whole grains, vegetables, and fruits. Enterolactone has been shown to have weak estrogenic and antiestrogenic properties. We decided to examine the association between plasma levels of enterolactone and mammographic density, a biomarker for breast cancer risk. METHODS: We included data from postmenopausal women ages 55 and older who participated in a cross-sectional mammogram study in Troms?, Norway. Mammograms, plasma enterolactone measurements, as well as information on anthropometric and hormonal/reproduction factors were available on 616 women. We assessed mammographic density using a previously validated computer-assisted method. We estimated correlation coefficients and conducted multiple regression analyses. RESULTS: Mean mammographic density increased slightly across quartiles of enterolactone; the women in the highest quartile had, on average, 3.1% (absolute difference) higher percentage mammographic density compared with the lowest quartile (P(trend) < 0.01). After adjustment for age, body mass index, number of full-term pregnancies, age at first birth, and use of postmenopausal hormone therapy, the mean difference in density was reduced to 2.0% (P(trend) = 0.05). Results were similar when restricted to the 454 current hormone nonusers. The fully adjusted statistical model explained 28.3% of the total variability in mammographic percentage density, with body mass index contributing 18.2% and enterolactone only 0.9%. CONCLUSION: In our study, higher levels of enterolactone were associated with slightly higher percentage mammographic density. Our results suggest that if higher enterolactone levels reduce the risk of developing breast cancer in postmenopausal women, then this effect is not through lowering mammographic density. 相似文献
10.
Summary Cellular accumulation of sulphatides after intracerebral and endoneurial injections of the lipid was shown to occur if mesenchymal cell proliferation is induced by cold injury to the brain or by transection of peripheral nerves. The cells accumulating the sulphatide in the brain were identified as mesenchymal phagocytes and in the peripheral nerves as endoneurial phagocytic cells.Accumulation of sulphatide was found in the epithelial cells of the renal collecting tubules after intracerebral injection of the lipid. This observation indicates that part of the renal sulphatide which can be demonstrated histochemically in the kidneys from cases of metachromatic leucodystrophy may derive from the brain and is excreted via the kidneys.
Zusammenfassung Celluläre Anhäufung von Sulfatiden nach intracerebralen und endoneuralen Injektionen des Lipids konnte nachgewiesen werden, wenn eine Proliferation von Mesenchymzellen durch Kälteverletzung des Gehirns oder durch Durchschneidung peripherer Nerven induziert wurde. Die mit Sulfatiden beladenen Zellen im Gehirn wurden als mesenchymale Phagocyten und in den peripheren Nerven als endoneurale Phagocytenzellen identifiziert.Anhäufung von Sulfatiden wurde nach intracerebraler Injektion des Lipids ferner in den Epithelzellen der Sammelstücke der Nierentubuli nachgewiesen. Dieser Befund weist darauf hin, daß ein Teil des renalen Sulfatides, das histochemisch in der Niere von Fällen metachromatischer Leukodystrophie nachgewiesen werden kann, teilweise aus dem Gehirn stammen könnte und über die Nieren ausgeschieden wird.相似文献