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31.
There is increasing evidence that climate change shifts species distributions towards poles and mountain tops. However, most studies are based on presence–absence data, and either abundance or the observation effort has rarely been measured. In addition, hardly any studies have investigated the direction of shifts and factors affecting them. Here, we show using count data on a 1000 km south–north gradient in Finland, that between 1970–1989 and 2000–2012, 128 bird species shifted their densities, on average, 37 km towards the north north‐east. The species‐specific directions of the shifts in density were significantly explained by migration behaviour and habitat type. Although the temperatures have also moved on average towards the north north‐east (186 km), the species‐specific directions of the shifts in density and temperature did not correlate due to high variation in density shifts. Findings highlight that climate change is unlikely the only driver of the direction of species density shifts, but species‐specific characteristics and human land‐use practices are also influencing the direction. Furthermore, the alarming results show that former climatic conditions in the north‐west corner of Finland have already moved out of the country. This highlights the need for an international approach in research and conservation actions to mitigate the impacts of climate change.  相似文献   
32.
Macrophages’ phenotypic and functional diversity depends on differentiating programs related to local environmental factors. Recent interest was deserved to the signal transduction pathways acting in macrophage polarization, including the phosphoinositide (PI) system and related phospholipase C (PLC) family of enzymes. The expression panel of PLCs and the subcellular localization differs in quiescent cells compared to the pathological counterpart. We analyzed the expression of PLC enzymes in unpolarized (M0), as well as in M1 and M2 macrophages to list the expressed isoforms and their subcellular localization. Furthermore, we investigated whether inflammatory stimulation modified the basal panel of PLCs’ expression and subcellular localization. All PLC enzymes were detected within both M1 and M2 cells, but not in M0 cells. M0, as well as M1 and M2 cells own a specific panel of expression, different for both genes’ mRNA expression and intracellular localization of PLC enzymes. The panel of PLC genes’ expression and PLC proteins’ presence slightly changes after inflammatory stimulation. PLC enzymes might play a complex role in macrophages during inflammation and probably also during polarization.  相似文献   
33.
Sediment surface samples (0–2 cm) from 66 sites, and longer cores (up to 540 cm) from 9 sites in the estuary of the river Kyrönjoki, Western Finland, were analysed for organic content, P, Fe, Mn, Pb, Cd, Cu and Zn. One core was dated on the basis of annual laminations.Chemical analyses of the cores showed that organic matter and heavy metal content have increased in recent decades. The heavy metal content was clearly lower than in areas polluted by industry. The sedimentation rate in the delta increased between the 1930s and 1950. It decreased in the 1960s, and has been below 1930s levels since 1970. The sedimentation rates of organic matter were fairly stable all through the period measured, even though the organic content increased.The increase in organic matter and the heavy metal content of the sediment in recent decades is evidently due to the increased intensity of agriculture, forestry and peat harvesting in the drainage basin. Drainage of peatlands in particular has increased erosion and the organic sediment load of the river. Reservoir building after 1970 has decreased the sedimentation rates in the delta.  相似文献   
34.
doi: 10.1111/j.1741‐2358.2010.00427.x Associations of instrumental activities of daily living and handgrip strength with oral self‐care among home‐dwelling elderly 75+ Objective: To study the associations of instrumental activities of daily living (IADL) and the handgrip strength with oral self‐care among dentate home‐dwelling elderly people in Finland. Materials and methods: The study analysed data for 168 dentate participants (mean age 80.6 years) in the population‐based Geriatric Multidisciplinary Strategy for Good Care of the Elderly (GeMS) study. Each participant received a clinical oral examination and structured interview in 2004–2005. Functional status was assessed using the IADL scale and handgrip strength was measured using handheld dynamometry. Results: Study participants with high IADL (scores 7–8) had odds ratios (ORs) for brushing their teeth at least twice a day of 2.7 [95% confidence intervals (CI) 1.1–6.8], for using toothpaste at least twice a day of 2.0 (CI 0.8–5.2) and for having good oral hygiene of 2.8 (CI 1.0–8.3) when compared with participants with low IADL (scores ≤6). Participants in the upper tertiles of the handgrip strength had ORs for brushing the teeth at least twice a day of 0.9 (CI 0.4–1.9), for using the toothpaste at least twice a day of 0.9 (CI 0.4–1.8) and for good oral hygiene of 1.1 (CI 0.5–2.4) in comparison with the study subjects in the lowest tertile of handgrip strength. Conclusion: The results of this study suggest that the functional status, measured by means of the IADL scale, but not handgrip strength, is an important determinant of oral self‐care among the home‐dwelling elderly.  相似文献   
35.
The stability against chemical denaturants of the elongation factor EF-1alpha (SsEF-1alpha), a protein isolated from the hyperthermophilic archaeon Sulfolobus solfataricus has been characterized in detail. Indeed, the atypical shape of the protein structure and the unusual living conditions of the host organism prompted us to analyze the effect of urea and guanidine hydrochloride (GuHCl) on the GDP complex of the enzyme (SsEF-1alpha x GDP) by fluorescence and circular dichroism. These studies were also extended to the nucleotide-free form of the protein (nfSsEF-1alpha). Interestingly, the experiments show that the denaturation curves of both SsEF-1alpha forms present a single inflection point, which is indicative of a cooperative unfolding process with no intermediate species. Moreover, the chemically induced unfolding process of both SsEF-1alpha x GDP and nfSsEF-1alpha is fully reversible. Both SsEF-1alpha forms exhibit remarkable stability against urea, but they do not display a strong resistance to the denaturing action of GuHCl. These findings suggest that electrostatic interactions significantly contribute to SsEF-1alpha stability.  相似文献   
36.
Several sphingolipid derivatives, including sphingosylphosphorylcholine (SPC), regulate a multitude of biological processes. In the present study we show that both human thyroid cancer cells (FRO cells) and normal human thyroid cells express G protein-coupled receptor 4 (GPR4) and ovarian cancer G protein-coupled receptor 1 (OGR1), putative SPC-specific receptors. In FRO cells SPC evoked a concentration-dependent increase in intracellular free calcium concentration ([Ca2+]i) in a calcium containing, but not in a calcium-free buffer. Sphingosine 1-phosphate (S1P) evoked an increase in [Ca2+]i in both a calcium containing and a calcium-free buffer. The phospholipase C (PLC) inhibitor U 73122 potently attenuated the effect of SPC, suggesting that effects of SPC were mediated by a G protein coupled receptor. Overnight pretreatment of the cells with pertussis toxin did not affect the SPC-evoked response. Interestingly, SPC did not evoke an increase in inositol phosphates, although S1P did so. Furthermore, in cells pretreated with thapsigargin to deplete intracellular calcium stores, SPC still evoked an increase in [Ca2+]i, suggesting that SPC mainly evoked entry of extracellular calcium. When the cells were pretreated with the protein kinase C (PKC) inhibitor GF 109203X, or when the cells were pretreated with PMA for 24 h, the SPC-evoked calcium entry was attenuated. Thus, the SPC-evoked calcium entry was apparently dependent on PKC. In sharp contrast, the increase in [Ca2+]i evoked by S1P was not sensitive to GF 109203X. Furthermore, the calcium entry evoked by the diacylglycerol analog 1-oleoyl-2-acetyl-sn-glycerol was not inhibited by GF 109203X. In addition, SPC decreased the incorporation of 3H-thymidine in a concentration-dependent manner in FRO cells. Taken together, SPC may be an important factor regulating thyroid cancer cell function.  相似文献   
37.
The plant Melissa officinalis L. has been used traditionally in the treatment of cognitive dysfunction. Based on its traditional medicinal use, it was assessed for its clinical efficacy in mild to moderate Alzheimer’s patients. The plant was effective in the management of the disease. Therefore, based on this result, a similar plant extract was prepared in order to be screened for bioactivities which are relevant in Alzheimer’s disease therapy. The extract was recently screened for antioxidant activity and it showed a wide range of antioxidant properties. Another important bioactivity is acetylcholinesterase inhibition, which the extract was screened for in the current investigation. The extract was capable of inhibiting the enzyme in a time and dose-dependent manner. Activity of the extract at 10 min was estimated as 1.72 ± 0.16 μg equivalents of physostigmine/mg of the extract. Acetylcholinesterase inhibitory guided fractionation of the extract was then carried out. Most of the fractions showed inhibitory activity and were more potent than the extract. The contents of the most potent fraction were identified as cis- and trans-rosmarinic acid isomers and a rosmarinic acid derivative using LC-DAD-ESI-MS and NMR methods.  相似文献   
38.
The purpose of this study was to detect local gloss and surface structure changes of sodium chloride tablets. The changes in surface structure were reflected by gloss variation, which was measured using a diffractive optical element-based gloss-meter (DOG). By scanning a surface area, we constructed a 2-dimensional gloss map that characterized the tablet’s surface structure. The gloss variation results were compared with scanning electron microscopy (SEM) images and average surface roughness values that were measured by conventional diamond stylus profilometry. The profilometry data showed a decrease in tablet surface roughness as a function of compression force. In general, a smoother surface contributes to higher average gloss values. The average gloss values for this material, in contrast, showed a decrease as a function of the compression force. The sequence of particle fragmentation and deformation together with crack formation in sodium chloride particles resulted in a loss of gloss for single sodium chloride particles at the tablet surfaces, which could be detected by the DOG. These results were supported by the SEM images. The results show that detailed information regarding tablets’ surface structure changes can be obtained by detection of local gloss variation and average gloss. Published: January 13, 2006  相似文献   
39.
Aim The role of biotic interactions in influencing species distributions at macro‐scales remains poorly understood. Here we test whether predictions of distributions for four boreal owl species at two macro‐scales (10 × 10 km and 40 × 40 km grid resolutions) are improved by incorporating interactions with woodpeckers into climate envelope models. Location Finland, northern Europe. Methods Distribution data for four owl and six woodpecker species, along with data for six land cover and three climatic variables, were collated from 2861 10 × 10 km grid cells. Generalized additive models were calibrated using a 50% random sample of the species data from western Finland, and by repeating this procedure 20 times for each of the four owl species. Models were fitted using three sets of explanatory variables: (1) climate only; (2) climate and land cover; and (3) climate, land cover and two woodpecker interaction variables. Models were evaluated using three approaches: (1) examination of explained deviance; (2) four‐fold cross‐validation using the model calibration data; and (3) comparison of predicted and observed values for independent grid cells in eastern Finland. The model accuracy for approaches (2) and (3) was measured using the area under the curve of a receiver operating characteristic plot. Results At 10‐km resolution, inclusion of the distribution of woodpeckers as a predictor variable significantly improved the explanatory power, cross‐validation statistics and the predictive accuracy of the models. Inclusion of land cover led to similar improvements at 10‐km resolution, although these improvements were less apparent at 40‐km resolution for both land cover and biotic interactions. Main conclusions Predictions of species distributions at macro‐scales may be significantly improved by incorporating biotic interactions and land cover variables into models. Our results are important for models used to predict the impacts of climate change, and emphasize the need for comprehensive evaluation of the reliability of species–climate impact models.  相似文献   
40.
Hou YZ  Zhao GR  Yang J  Yuan YJ  Zhu GG  Hiltunen R 《Life sciences》2004,75(14):1775-1786
Ligusticum chuanxiong and Angelica sinensis have been widely used in traditional Chinese medicine to treat some pathological settings such as atherosclerosis and hypertension. We determined the protective effect of the extract of Ligusticum chuanxiong and Angelica sinensis (ELCAS) on human umbilical vein endothelial cells (ECV304) damage induced by hydrogen peroxide. ECV304 cells were pre-treated with ELCAS and exposed to 5 mM hydrogen peroxide. The results show that ELCAS dose- and time-dependently protected ECV304 cells against hydrogen peroxide damage and suppressed the production of reactive oxygen species (ROS). The decrement of ROS may be associated with increased activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). Western blot analysis revealed that ELCAS significantly increased the phosphorylation of ERK and promoted eNOS expression. These observations indicate that ELCAS protected ECV304 cells against hydrogen peroxide damage by enhancing the antioxidative ability, activating ERK and eNOS signaling pathway. Our data also provide new evidence of Ligusticum chuanxiong and Angelica sinensis in preventing both cardiovascular and cerebrovascular diseases.  相似文献   
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