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171.
Karl A Franklin Christer Janson Thórarinn Gíslason Amund Gulsvik Maria Gunnbj?rnsdottir Birger N Laerum Eva Lindberg Eva Norrman Lennarth Nystr?m Ernst Omenaas Kjell Torén Cecilie Svanes 《Respiratory research》2008,9(1):63
Background
To our knowledge, no studies of the possible association of early life environment with snoring in adulthood have been published. We aimed to investigate whether early life environment is associated with snoring later in life.Methods
A questionnaire including snoring frequency in adulthood and environmental factors in early life was obtained from 16,190 randomly selected men and women, aged 25–54 years, in Sweden, Norway, Iceland, Denmark and Estonia (response rate 74%).Results
A total of 15,556 subjects answered the questions on snoring. Habitual snoring, defined as loud and disturbing snoring at least 3 nights a week, was reported by 18%. Being hospitalized for a respiratory infection before the age of two years (adjusted odds ratio (OR) = 1.27; 95% confidence interval (CI) 1.01–1.59), suffering from recurrent otitis as a child (OR = 1.18; 95%CI 1.05–1.33), growing up in a large family (OR = 1.04; 95%CI 1.002–1.07) and being exposed to a dog at home as a newborn (OR = 1.26; 95%CI 1.12–1.42) were independently related to snoring later in life and independent of a number of possible confounders in adulthood. The same childhood environmental factors except household size were also related with snoring and daytime sleepiness combined.Conclusion
The predisposition for adult snoring may be partly established early in life. Having had severe airway infections or recurrent otitis in childhood, being exposed to a dog as a newborn and growing up in a large family are environmental factors associated with snoring in adulthood. 相似文献172.
173.
Maribasappa Karched Riikka Ihalin Kjell Eneslätt Deyu Zhong Jan Oscarsson Sun N Wai Casey Chen Sirkka E Asikainen 《BMC microbiology》2008,8(1):18
Background
Aggregatibacter actinomycetemcomitans is an oral bacterium associated with aggressively progressing periodontitis. Extracellular release of bacterial outer membrane proteins has been suggested to mainly occur via outer membrane vesicles. This study investigated the presence and conservation of peptidoglycan-associated lipoprotein (AaPAL) among A. actinomycetemcomitans strains, the immunostimulatory effect of AaPAL, and whether live cells release this structural outer membrane lipoprotein in free-soluble form independent of vesicles. 相似文献174.
Woods AS Marcellino D Jackson SN Franco R Ferré S Agnati LF Fuxe K 《Journal of proteome research》2008,7(8):3428-3434
Receptor heteromerization is a mechanism used by G protein-coupled receptors to diversify their properties and function. We previously demonstrated that these interactions occur through salt bridge formation between epitopes of the involved receptors. Recent studies claim that calmodulin (CaM) binds to an Arg-rich epitope located in the amino-terminus of the dopamine D(2) receptor third intracellular loop. This is the same epitope involved in adenosine A(2A)-D(2) receptor heteromerization, through Coulombic interaction between the Arg residues and a phosphorylated serine (pS) located in the medial segment of the C-terminus of the A(2A) receptor. Mass spectrometric analysis indicates that an electrostatic interaction involving the D(2) receptor Arg-rich epitope and several CaM acidic epitopes are mainly responsible for the D(2) receptor-CaM binding. CaM could also form multiple noncovalent complexes by means of electrostatic interactions with an epitope localized in the proximal segment of the C-terminus of the A(2A) receptor. Ca(2+) disrupted the binding of CaM to the D(2) but not to the A(2A) receptor epitope, and CaM disrupted the electrostatic interactions between the D(2) receptor epitope and the more distal A(2A) receptor epitope. A model is introduced with the possible functional implications of A(2A)-D(2)-CaM interactions. These in vitro findings imply a possible regulatory role for CaM in receptor heteromers formation. 相似文献
175.
Seasonal variations in olfactory sensory neurons--fish sensitivity to sex pheromones explained? 总被引:1,自引:0,他引:1
Olfactory sensory neurons of vertebrates regenerate throughout the life of the animal. In fishes, crypt cells are a type of olfactory sensory neurons thought to respond to sex pheromones. Here, we demonstrate that the number of crypt cells in the olfactory epithelium of the crucian carp varies dramatically throughout the year. During winter, few crypt cells are observed at any location within the sensory epithelium. In spring, the majority of crypt cells are located deep in the epithelium not yet exposed to the environment. However, during the summer spawning season, crypt cells are positioned at the epithelial surface. These findings may explain previous studies demonstrating a relationship between circulating androgen and olfactory sensitivity to sex pheromones. 相似文献
176.
Otso Suominen Inga‐Lill Persson Kjell Danell Roger Bergström John Pastor 《Ecography》2008,31(5):636-645
Large herbivores can affect vegetation structure and species composition as well as material and energy flows in the ecosystem through their selective feeding, defecation, urination and trampling. These changes have a large potential to indirectly affect other trophic levels, but the mechanisms are poorly known. We studied the impacts of moose Alces alces browsing along a gradient of site productivity by experimentally simulating four different moose densities. Here we show that moose can affect the richness and abundance of three trophic levels in Swedish boreal forests through complex direct and indirect impacts, but in qualitatively different ways depending on how the physical habitat or food resources of a trophic level are affected. Vegetation richness had a hump‐shaped (unimodal) response to increased moose density. Leaf litter production decreased when browsing increased, which in turn depressed the abundance of flying prey for spiders. Consequently, spider abundance and richness declined monotonically. The responses of spider richness to moose density were further conditioned by site productivity: the response was positive at productive and negative at unproductive sites. In contrast, herbivorous Hemiptera were not affected by moose, most likely because the abundance of their food plants was not affected. The highest simulated moose density had an impact on all variables responding to moose even after a few years of treatment and can be considered as overabundance. We also show that the impacts of low or moderate moose density can be positive to some of the organisms negatively affected by high density. The level of herbivore population density that leads to substantial community impacts also depends on site factors, such as productivity. 相似文献
177.
Hildur Helgadottir Emilia Andersson Lisa Villabona Lena Kanter Henk van der Zanden Geert W. Haasnoot Barbara Seliger Kjell Bergfeldt Johan Hansson Boel Ragnarsson-Olding Rolf Kiessling Giuseppe Valentino Masucci 《Cancer immunology, immunotherapy : CII》2009,58(10):1599-1608
Purpose We have previously demonstrated an association of the human leukocyte antigen (HLA), HLA-A2 allele with ovarian and prostate
cancer mortality as well as a segregation of the ancestral HLA haplotype (AHH) 62.1 [(A2) B15 Cw3 DRB1*04] in patients with
stage III–IV serous ovarian cancer. The objective of the present study was to determine the role of the HLA phenotype on the
prognosis in stage III–IV malignant melanoma patients.
Patients and methods A cohort of metastatic malignant melanoma patients (n = 91), in stage III (n = 26) or IV (n = 65) were analysed for HLA-A, -B, -Cw and -DRB1 types by PCR/sequence-specific primer method. The frequencies of HLA alleles
in the patients were compared to that of healthy Swedish bone marrow donors. The effect of HLA types on prognosis was defined
by Kaplan–Meier and Cox analysis.
Results The presence of the AHH 62.1 in clinical stage IV patients was significantly and independently associated with the worst survival
rate recorded from the appearance of metastasis (HR = 2.14; CI = 1.02–4.4; P = 0.04). In contrast, the period from the primary diagnosis to metastasis was the longest in patients with this haplotype
(HR = 0.40; CI = 0.17–0.90; P = 0.02).
Conclusions Melanoma patients in our cohort with 62.1 AHH which is associated with autoimmune diseases have an initial strong anti-tumour
control with longer metastasis-free period. These patients have rapid progression after the appearance of metastasis, responding
poorly to chemo- or/and immunotherapy. This apparently paradoxical clinical process could be due to the interplay between
tumour clones escape and immune surveillance ending up with a rapid disease progression.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
178.
Kjell Nordberg Helena L. Filipsson Pernilla Linn Mikael Gustafsson 《Marine Micropaleontology》2009,73(1-2):117-128
Significant faunal changes reported from recent, coastal environments, which are not directly influenced by urban and industrial impact, are rarely seen. In Gullmar Fjord on the Swedish west coast, a significant foraminiferal fauna change occurred in connection with severe low-oxygen conditions that evolved in the winter of 1979/1980. A foraminiferal fauna marked by common Skagerrak–Kattegat species, which had previously characterised the deep fjord basin, was replaced by the opportunistic, low-oxygen tolerant species Stainforthia fusiformis (Williamsson).To study this phenomenon further we performed stable oxygen and carbon isotope analyses on the indicator species itself, S. fusiformis, both on specimens from sediment cores representing approximately the last 85 years and on living (stained) individuals taken from a transect across the deep fjord basin. Our purpose was to detail how and why S. fusiformis, came to dominate the fauna.The oxygen isotope results suggest that salinities and temperatures in the deep basin have been relatively constant over the last c. 85 years, while the carbon isotopes show a significant change towards more negative values in association with the faunal shift of 1979/1980. The combined results from both the cores and the surface sediments suggest that S. fusiformis did not inhabit the deep basin until 1980. Before then, almost all specimens of S. fusiformis were small sized and their carbon isotope values suggest they were re-deposited shallow-water specimens that had been transported down to the central, deep basin as part of a suspension load. After a major faunal extinction in 1979–1980, S. fusiformis of all sizes suddenly appeared in large numbers and their carbon isotopic values were similar to the signal from registered in the recent, living fauna within the deep basin. This suggests that the opportunistic S. fusiformis established itself in the deep basin as a consequence of the severe low-oxygen event and the faunal crash of the previously dominating Skagerrak–Kattegat fauna. 相似文献
179.
Mathieu Basille Ivar Herfindal Hugues Santin‐Janin John D. C. Linnell John Odden Reidar Andersen Kjell Arild Høgda Jean‐Michel Gaillard 《Ecography》2009,32(4):683-691
In the multi-use landscape of southern Norway, the distribution of lynx is likely to be determined both by the abundance of their favoured prey – the roe deer – and the risk associated with the presence of humans because most lynx mortalities are caused by humans (recreational harvest, poaching, vehicle collisions). We described the distribution of the reproductive portion of the lynx population based on snow-track observations of females with dependent kittens collected over 10 yr (1997–2006) in southern Norway. We used the ecological-niche factor analysis to examine how lynx distribution was influenced by roe deer, human activity, habitat type, environmental productivity and elevation. Our first prediction that lynx should be found in areas of relatively high roe deer abundance was supported. However, our second prediction that lynx should avoid human activity was rejected, and lynx instead occupied areas more disturbed in average than those available (with the exception of the most densely occupied areas). Lynx, however, avoided the most disturbed areas and our third prediction of a trade-off between abundance of prey and avoidance of human activity was supported. On the one hand, roe deer in the most disturbed areas benefit to a large extent from current human land use practices, potentially allowing them to escape predation from lynx. On the other hand, the situation is not so favourable for the predators who are restricted in competition refuges with medium to low prey densities. The consequence is that lynx conservation will have to be achieved in a human modifed environment where the potential for a range of conflicts and high human-caused mortality will remain a constant threat. 相似文献
180.