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81.
Xoaquín Moreira Luis Abdala-Roberts Pieter De Frenne Andrea Galmán Álvaro Gaytán Raimo Jaatinen Beatriz Lago-Núñez Camille Meeussen Pertti Pulkkinen Pil U. Rasmussen Jan P.J.G. Ten Hoopen Bart G.H. Timmermans Carla Vázquez-González Nick Bos Bastien Castagneyrol Ayco J.M. Tack 《American journal of botany》2021,108(1):172-176
82.
Raija Uusitalo-Sepp?l? Reetta Huttunen Janne Aittoniemi Pertti Koskinen Aila Leino Tero Vahlberg Esa M. Rintala 《PloS one》2013,8(1)
Background
Early diagnostic and prognostic stratification of patients with suspected infection is a difficult clinical challenge. We studied plasma pentraxin 3 (PTX3) upon admission to the emergency department in patients with suspected infection.Methods
The study comprised 537 emergency room patients with suspected infection: 59 with no systemic inflammatory response syndrome (SIRS) and without bacterial infection (group 1), 67 with bacterial infection without SIRS (group 2), 54 with SIRS without bacterial infection (group 3), 308 with sepsis (SIRS and bacterial infection) without organ failure (group 4) and 49 with severe sepsis (group 5). Plasma PTX3 was measured on admission using a commercial solid-phase enzyme-linked immunosorbent assay (ELISA).Results
The median PTX3 levels in groups 1–5 were 2.6 ng/ml, 4.4 ng/ml, 5.0 ng/ml, 6.1 ng/ml and 16.7 ng/ml, respectively (p<0.001). The median PTX3 concentration was higher in severe sepsis patients compared to others (16.7 vs. 4.9 ng/ml, p<0.001) and in non-survivors (day 28 case fatality) compared to survivors (14.1 vs. 5.1 ng/ml, p<0.001). A high PTX3 level predicted the need for ICU stay (p<0.001) and hypotension (p<0.001). AUCROC in the prediction of severe sepsis was 0.73 (95% CI 0.66–0.81, p<0.001) and 0.69 in case fatality (95% CI 0.58–0.79, p<0.001). PTX3 at a cut-off level for 14.1 ng/ml (optimal cut-off value for severe sepsis) showed 63% sensitivity and 80% specificity. At a cut-off level 7.7 ng/ml (optimal cut-off value for case fatality) showed 70% sensitivity and 63% specificity in predicting case fatality on day 28.In multivariate models, high PTX3 remained an independent predictor of severe sepsis and case fatality after adjusting for potential confounders.Conclusions
A high PTX3 level on hospital admission predicts severe sepsis and case fatality in patients with suspected infection. 相似文献83.
Juha Grönroos Jyri Seppälä Sirkka Koskela Antti Kilpeläinen Pekka Leskinen Anne Holma Juha-Pekka Tuovinen Jukka Turunen Saara Lind Marja Maljanen Pertti J. Martikainen 《The International Journal of Life Cycle Assessment》2013,18(3):567-576
Purpose
There has been lively debate, especially in Finland and Sweden, on the climate impacts of peat fuel. Previous studies of peat fuel's life-cycle climate impacts were controversial in their interpretation. The aim of this paper is conclusive examination of the issues of LCA methodology, derived from critical review of previous studies and recalculation based on the latest knowledge of greenhouse gas balances related to peat fuel’s utilisation and the radiative forcing impacts of greenhouse gases.Methods
The most recent findings on emissions and the gas fluxes between soil, vegetation and atmosphere were used in calculation of the life-cycle climate impacts of the various peat fuel utilisation chains by means of LCA methodology. In the main, the calculation methods and rules were the same as in the previous studies, with the aim being to distinguish the impact of peat fuel’s utilisation from that of the natural or semi-natural situation. A dynamic method was employed for assessing changes in radiative forcing. The results of alternative peat fuel utilisation chains were compared to the corresponding result for coal.Results
There are many steps in peat fuel LCA, where different assumptions lead to different outcomes. Determining the functional unit, reference situations and system boundaries, as well as the emission calculation methods, is important from this point of view. Determination of the initial reference situation emerged as one of the critical points in the calculations. Time scale can strongly affect the final outcomes in a study where effects of long-term land-use change are considered.Conclusions
Each peatland area is unique. The higher the greenhouse gas emissions in the initial reference situation, the greater is the climate impact of the area and the more suitable the area is for peat extraction. The study showed that more greenhouse gas flux measurements are needed, for better assessment of the climate impacts of different potential peat extraction sites. Climate change mitigation requires quick actions, and uncertainties related to emissions are higher for longer time spans. Therefore, it can be concluded that a perspective spanning more than 100 years is inappropriate in peat fuel's life-cycle climate impact assessments. 相似文献84.
Load application induces changes in the expression levels of Sox-9, FGFR-3 and VEGF in condylar chondrocytes 总被引:1,自引:0,他引:1
Papadopoulou AK Papachristou DJ Chatzopoulos SA Pirttiniemi P Papavassiliou AG Basdra EK 《FEBS letters》2007,581(10):2041-2046
Experimental and clinical observations have proven the modulatory effects of mechanical loading on the development and maintenance of cartilage architecture. Here we examined the involvement of Sox-9, FGFR-3 and VEGF (pivotal factors controlling cartilage development and growth) in the mechano-transduction pathway of mandibular condylar cartilage by changing the dynamics of the transmitted load via changes in food hardness. To this end, condyle cartilage tissue of rats fed with hard or soft food was analyzed immunohistochemically at various time points. Our findings demonstrate that different mechanical loading conditions in condylar chondrocytes trigger differentiation-/maturation-related processes by affecting the expression levels of these factors, ultimately influencing condylar cartilage growth. 相似文献
85.
Shamsiiat Abdurakhmanova Svetlana Semenova T. Petteri Piepponen Pertti Panula 《Genes, Brain & Behavior》2019,18(8)
Hypothalamic histaminergic neurons regulate a variety of homeostatic, metabolic and cognitive functions. Recent data have suggested a modulatory role of histamine and histamine receptors in shaping striatal activity and connected the histaminergic system to neuropsychiatric disorders. We characterized exploratory behavior and striatal neurotransmission in mice lacking the histamine producing enzyme histidine decarboxylase (Hdc). The mutant mice showed a distinct behavioral pattern during exploration of novel environment, specifically, increased frequency of rearing seated against the wall, jumping and head/body shakes. This behavioral phenotype was associated with decreased levels of striatal dopamine and serotonin and increased level of dopamine metabolite DOPAC. Gene expression levels of dynorphin and enkephalin, opioids released by medium spiny neurons of striatal direct and indirect pathways respectively, were lower in Hdc mutant mice than in control animals. A low dose of amphetamine led to similar behavioral and biochemical outcomes in both genotypes. Increased striatal dopamine turnover was observed in Hdc KO mice after treatment with dopamine precursor l ‐Dopa. Overall, our study suggests a role for striatal dopamine and opioid peptides in formation of distinct behavioral phenotype of Hdc KO mice. 相似文献
86.
Greenhouse gas fluxes from the eutrophic Temmesjoki River and its Estuary in the Liminganlahti Bay (the Baltic Sea) 总被引:2,自引:0,他引:2
Hanna Silvennoinen Anu Liikanen Jaana Rintala Pertti J. Martikainen 《Biogeochemistry》2008,90(2):193-208
We studied concentrations of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) in the eutrophic Temmesjoki River and Estuary in the Liminganlahti Bay in 2003–2004 and evaluated the atmospheric fluxes
of the gases based on measured concentrations, wind speeds and water current velocities. The Temmesjoki River was a source
of CO2, CH4 and N2O to the atmosphere, whereas the Liminganlahti Bay was a minor source of CH4 and a minor source or a sink of CO2 and N2O. The results show that the fluxes of greenhouse gases in river ecosystems are highly related to the land use in its catchment
areas. The most upstream river site, surrounded by forests and drained peatlands, released significant amounts of CO2 and CH4, with average fluxes of 5,400 mg CO2–C m−2 d−1 and 66 mg CH4–C m−2 d−1, and concentrations of 210 μM and 345 nM, respectively, but N2O concentrations, at an average of 17 nM, were close to the atmospheric equilibrium concentration. The downstream river sites
surrounded by agricultural soils released significant amounts of N2O (with an average emission of 650 μg N2O–N m−2 d−1 and concentration of 22 nM), whereas the CO2 and CH4 concentrations were low compared to the upstream site (55 μM and 350 nM). In boreal regions, rivers are partly ice-covered
in wintertime (approximately 5 months). A large part of the gases, i.e. 58% of CO2, 55% of CH4 and 36% of N2O emissions, were found to be released during wintertime from unfrozen parts of the river. 相似文献
87.
Warming of subarctic tundra increases emissions of all three important greenhouse gases – carbon dioxide,methane, and nitrous oxide
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Carolina Voigt Richard E. Lamprecht Maija E. Marushchak Saara E. Lind Alexander Novakovskiy Mika Aurela Pertti J. Martikainen Christina Biasi 《Global Change Biology》2017,23(8):3121-3138
Rapidly rising temperatures in the Arctic might cause a greater release of greenhouse gases (GHGs) to the atmosphere. To study the effect of warming on GHG dynamics, we deployed open‐top chambers in a subarctic tundra site in Northeast European Russia. We determined carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes as well as the concentration of those gases, inorganic nitrogen (N) and dissolved organic carbon (DOC) along the soil profile. Studied tundra surfaces ranged from mineral to organic soils and from vegetated to unvegetated areas. As a result of air warming, the seasonal GHG budget of the vegetated tundra surfaces shifted from a GHG sink of ?300 to ?198 g CO2–eq m?2 to a source of 105 to 144 g CO2–eq m?2. At bare peat surfaces, we observed increased release of all three GHGs. While the positive warming response was dominated by CO2, we provide here the first in situ evidence of increasing N2O emissions from tundra soils with warming. Warming promoted N2O release not only from bare peat, previously identified as a strong N2O source, but also from the abundant, vegetated peat surfaces that do not emit N2O under present climate. At these surfaces, elevated temperatures had an adverse effect on plant growth, resulting in lower plant N uptake and, consequently, better N availability for soil microbes. Although the warming was limited to the soil surface and did not alter thaw depth, it increased concentrations of DOC, CO2, and CH4 in the soil down to the permafrost table. This can be attributed to downward DOC leaching, fueling microbial activity at depth. Taken together, our results emphasize the tight linkages between plant and soil processes, and different soil layers, which need to be taken into account when predicting the climate change feedback of the Arctic. 相似文献
88.
Piritta Hynninen Jonna M H?m?l?inen Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S Sly Eija Tomas Pertti Kirkinen Seppo Parkkila 《Reproductive biology and endocrinology : RB&E》2004,2(1):73
Background
Carbonic anhydrase (CA) classically catalyses the reversible hydration of dissolved CO2 to form bicarbonate ions and protons. The twelve active CA isozymes are thought to regulate a variety of cellular functions including several processes in the reproductive systems. 相似文献89.
Air temperature triggers the recovery of evergreen boreal forest photosynthesis in spring 总被引:11,自引:0,他引:11
Suni Tanja Frank Berninger† Timo Vesala Tiina Markkanen Pertti Hari† Annikki Mäkelä† Hannu Ilvesniemi† Heikki Hänninen‡ Eero Nikinmaa† Timo Huttula Tuomas Laurila§ Mika Aurela§ Achim Grelle¶ ers Lindroth Almut Arneth Olga Shibistova†† Jon Lloyd 《Global Change Biology》2003,9(10):1410-1426
The timing of the commencement of photosynthesis (P*) in spring is an important determinant of growing‐season length and thus of the productivity of boreal forests. Although controlled experiments have shed light on environmental mechanisms triggering release from photoinhibition after winter, quantitative research for trees growing naturally in the field is scarce. In this study, we investigated the environmental cues initiating the spring recovery of boreal coniferous forest ecosystems under field conditions. We used meteorological data and above‐canopy eddy covariance measurements of the net ecosystem CO2 exchange (NEE) from five field stations located in northern and southern Finland, northern and southern Sweden, and central Siberia. The within‐ and intersite variability for P* was large, 30–60 days. Of the different climate variables examined, air temperature emerged as the best predictor for P* in spring. We also found that ‘soil thaw’, defined as the time when near‐surface soil temperature rapidly increases above 0°C, is not a useful criterion for P*. In one case, photosynthesis commenced 1.5 months before soil temperatures increased significantly above 0°C. At most sites, we were able to determine a threshold for air‐temperature‐related variables, the exceeding of which was required for P*. A 5‐day running‐average temperature (T5) produced the best predictions, but a developmental‐stage model (S) utilizing a modified temperature sum concept also worked well. But for both T5 and S, the threshold values varied from site to site, perhaps reflecting genetic differences among the stands or climate‐induced differences in the physiological state of trees in late winter/early spring. Only at the warmest site, in southern Sweden, could we obtain no threshold values for T5 or S that could predict P* reliably. This suggests that although air temperature appears to be a good predictor for P* at high latitudes, there may be no unifying ecophysiological relationship applicable across the entire boreal zone. 相似文献
90.