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1.
A Che?mońska-Soyta M Zimecki W Nowacki M Niko?ajczuk 《Comparative immunology, microbiology and infectious diseases》2001,24(3):151-164
We investigated the influence of heparin, one of the extracellular matrix (ECM) components, on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by bovine peripheral blood mononuclear cells (PBMC) and monocytes left to adhere for 2 (freshly adherent monocytes) and 48 h (resting monocytes), activated with Salmonella typhimurium lipopolysaccharide (LPS). After 24-h stimulation with LPS, heparin (100 microg/ml) increased (by about 40%) NO production by peripheral blood mononuclear cells and by freshly adherent monocytes. However, it did not change NO synthesis by the resting monocytes. Unlike its influence on NO level, heparin diminished TNF-alpha production by PBMC and monocytes stimulated with LPS. Microscopical examination of PBMC stained with biotin-labeled heparin, showed that both lymphocytes and monocytes were able to bind this glycosaminoglycan. We suggest that heparin, as a component of ECM, modulates the early response of monocytes to exogenous stimuli. 相似文献
2.
Integrated assessment models were applied to analyze the side-benefits of structural changes in the energy systems of Finland and the EU to reduce acidity critical load exceedances in Finland. The acidification reduction potential of structural measures, induced by the need to restrict carbon dioxide (CO2) emissions, was compared with international agreements limiting acidifying emissions. The impacts of the UN/ECE Gothenburg protocol and the European Commission's proposal for a National Emission Ceilings (NEC) Directive were assessed together with domestic and bilateral policy scenarios. The study utilized point-source emission databases of Finland and the neighboring areas and a meso-scale deposition model together with the Europewide transfer matrices of the EMEP/MSC-W and European emission scenarios of IIASA. Further technical reduction measures in the adjacent large sulfur emission sources in Russia would reduce considerably deposition to nearby Finnish areas. Energy saving and shifts in the EU energy system towards less carbon-intensive fuels instead of further technical emission controls were found to have significant potential in limiting acidifying deposition. Implementation of the Kyoto protocol in the EU could reduce the Finnish areas at risk of acidification more than the Gothenburg protocol and the NEC Directive together. 相似文献
3.
The evolutionarily conserved actin-related protein (Arp2/3) complex is a key component of actin filament networks that is dynamically regulated by nucleation-promoting and inhibitory factors. Although much is known about actin assembly, the physiologic functions of inhibitory proteins are unclear. We generated coronin 1-/- mice and found that coronin 1 exerted an inhibitory effect on cellular steady-state F-actin formation via an Arp2/3-dependent mechanism. Whereas coronin 1 was required for chemokine-mediated migration, it was dispensable for T cell antigen receptor functions in T cells. Moreover, actin dynamics, through a mitochondrial pathway, was linked to lymphocyte homeostasis. 相似文献
4.
The study was carried out to assess the economic burden of trypanosomosis in three villages of the Metekel zone in 2009. The
disease was found to cause substantial economic losses through cattle mortality, drug purchase, and draft power loss of infected
oxen. The farmers in the area were spending a significantly (p < 0.05) higher amount of money for the treatment of trypanosomosis than all other diseases combined. The overall mortality
rate of cattle due to trypanosomosis was 4.4%. The mortality was significantly higher (p < 0.05) in an area where trypanosomosis prevalence was also higher. Many of the farmers prioritized losses of draft power
as the most important impact of the disease. The overall prevalence of the disease was 12.1%. The disease burden was significantly
(p < 0.05) higher in the rainy season than at other times of the year. In general, farmers had good knowledge on the signs and
seasonality of trypanosomosis. Thus, tsetse suppression activities that involve the local community can be an important tool
towards minimizing the economic burden of the disease in the area. 相似文献
5.
Interpretation of the result of a diagnostic test depends not only on the actual test result(s) but also on information external to this result, namely the test's sensitivity and specificity. This external information (also called prior information) must be combined with the data to yield the so-called updated, posterior estimates of the true prevalence and the test characteristics. The Bayesian approach offers a natural, intuitive framework in which to carry out this estimation process. The influence of the prior information on the final result may not be ignored. Guidance for the choice of prior information not in conflict with the data can be obtained from a set of statistics and indices (DIC, p(D), Bayes-p). 相似文献
6.
Blagojević P Radulović N Palić R Stojanović G 《Journal of agricultural and food chemistry》2006,54(13):4780-4789
The chemical composition of the aerial and root essential oils, hydrodistilled from Artemisia absinthium L. and Artemisia vulgaris L. (wild-growing populations from Serbia), were studied by gas chromatography, gas chromatography-mass spectrometry, and 13C nuclear magnetic resonance. During the storage of plant material under controlled conditions, a significant decrease of essential oil yields (isolated directly after drying and after 1 year of storage) and significant differences in their chemical compositions were observed. A possible mechanism for the observed oil component interconversion has been discussed. The noticeable differences in the chemical composition of the oils isolated from roots and aerial parts of A. absinthium and A. vulgaris were also correlated with the diverging biosynthetic pathways of volatiles in the respective plant organs. The antimicrobial activities against the common human pathogens of all of the isolated oils were tested according to National Committee on Clinical Laboratory Standards. The oils showed a broad spectrum of antimicrobial activity against the tested strains. Therefore, these oils can be used as flavor and fragrance ingredients. 相似文献
7.
De Waele V Berzano M Speybroeck N Berkvens D Mulcahy GM Murphy TM 《Veterinary parasitology》2012,189(2-4):366-368
In order to clarify if a peri-parturient rise of Cryptosporidium parvum oocysts occurs in cows, faecal samples from 42 cows on two farms were collected. These samples were taken during the pre-parturient, the peri-parturient and the post-parturient periods. Two methods were used to detect the oocysts, a nested-PCR coupled with sequencing and a duplex real-time PCR (qPCR) that quantified Cryptosporidium spp. DNA concentration. The qPCR results were adjusted using a hierarchical Bayesian model taking into account within and between run variation. Generalised Estimating Equation models (GEE) were used to determine if peri-parturient cows were at greater risk of being infected than pre- or post-parturient cows. Fourteen dairy cows exhibited a peri-parturient and post-parturient rise in the excretion of Cryptosporidium spp. oocysts, other than the zoonotic C. parvum. The cows in the suckler beef farm were the only ones infected with the zoonotic species C. parvum at calving. Due to the low concentration of oocysts excreted mainly from species other than C. parvum, it would appear unlikely that cows act as a source of infection for their calves or contribute significantly to environmental contamination. 相似文献
8.
Tapani Hirvonen Joni Orava Niko Penttinen Katri Luostarinen Markku Hauta-Kasari Mika Sorjonen Kai-Erik Peiponen 《Wood Science and Technology》2014,48(5):995-1003
In this study, a comprehensive spectral image database of Nordic sawn timbers for public use was measured. Economically significant Finnish wood species birch (Betula sp.), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) were chosen for inclusion in the database. The total of samples was 107 containing heartwood, sapwood, decayed wood, blue stain, mold, resin, early wood, late wood, knots, cracks, pith, reaction wood and bark. Board and crosscut samples were measured in frozen, melted and room-dried conditions. The reflectance of samples was measured over a 300- to 2,500-nm wavelength range. Additionally, the photoluminescence of samples excited by an ultraviolet B light source was measured. The spot size used was 250 μm with an 80 mm \(\times \) 200 mm imaging area, and produced all in all 44 million spectra. In this paper, examples of the possibilities of this spectral image database as a means of detection of the spatial distribution of aromatic lignin and the moisture content (MC) of nonfrozen timber were introduced and provided. From the results, it was found that it was possible to detect the lignin distribution from spectral images, and simple and robust methods for wood MC estimations were also introduced. 相似文献
9.
Elise Monsieurs Mekete Dessie Enyew Adgo Jean Poesen Jozef Deckers Niko Verhoest Jan Nyssen 《Land Degradation \u0026amp; Development》2015,26(1):35-44
The combination of runoff‐generating areas (saturated soils) and overland flow concentration in features such as drainage ditches makes sloping farmland vulnerable to soil erosion. The establishment of drainage ditches aims at draining the excess of water from the farmland, particularly in areas where soils are saturated in the rainy season. The hydrogeomorphic impacts on the farmland itself and on downstream areas need however also to be studied. Off site, downstream problems comprise higher peak discharges, leading to gully initiation, an increase in sediment load, and flooding problems. On‐site problems such as the development of the drainage ditches into (ephemeral) gullies are less documented, although they may be important, as illustrated in the Lake Tana Basin (Ethiopia). The similarities and interactions between ephemeral gully channels and drainage ditches have to be considered to better understand all effects of drainage. Drainage ditches are a potential source of conflict between farmers with different interests and power, as well as between upstream and downstream users. A case study on drainage ditches on sloping farmlands in the Lake Tana Basin showed that nine out of ten catchments had drainage densities by ditches ranging from 53 to 510 m ha−1. Drainage ditches were constructed with an average top width of 27 (±9) cm. A significant correlation was found between stone bund density (physical conservation structures) and ditch drainage density (R = −0·72), in line with the Ethiopian government's ban on drainage ditches in farmlands where stone bunds have been constructed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.
The clear dependence of N2O production through denitrification on available nitrate in soil has been shown in many studies. Since N availability similarly limits the growth of plants, the resource competition with vegetation limits the activity of denitrifying microbes and may consequently moderate the N2O emissions from peatlands. We used uptake by Eriophorum vaginatum L. as a vegetation competition factor for microbes. The species was selected for the experiment because it has high nutrient use efficiency in low-nutrient conditions and high nutrient uptake efficiency in luxuriant nutrient conditions. We measured gaseous N flux as N2O (end product of denitrifier activity) in a restored peatland in central Finland with acetylene inhibition technique over a growing season from sample plots with varying addition levels and E. vaginatum cover. The resource competition effects were analysed with a model that used exponential decay dependence of N2O flux on the leaf area of E. vaginatum, and saturating response of N2O flux to addition level. The model explained the variation in N2O fluxes well (R2=0.86). The model simulation showed that the increasing nutrient uptake of E. vaginatum decreased the N2O fluxes exponentially. Simultaneously, denitrification appeared to saturate even in conditions with high availability of and low level of competition by vegetation. Thus, E. vaginatum is an effective competitor for in sedge-dominated peatlands that controls the availability of for denitrification, and consequently moderates the N2O emissions from peatlands. 相似文献