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971.
Liljana Gentschew Femke‐Anouska Heinsen Amke Caliebe Lene Christiansen Marianne Nygaard Kaare Christensen Hélène Blanché Jean‐François Deleuze Céline Derbois Pilar Galan Carsten Büning Stephan Brand Anette Peters Konstantin Strauch Martina Müller‐Nurasyid Per Hoffmann Markus M. Nöthen Wolfgang Lieb Andre Franke Stefan Schreiber Almut Nebel 《Aging cell》2016,15(3):585-588
Human longevity is characterized by a remarkable lack of confirmed genetic associations. Here, we report on the identification of a novel locus for longevity in the RAD50/IL13 region on chromosome 5q31.1 using a combined European sample of 3208 long‐lived individuals (LLI) and 8919 younger controls. First, we performed a large‐scale association study on 1458 German LLI (mean age 99.0 years) and 6368 controls (mean age 57.2 years) by targeting known immune‐associated loci covered by the Immunochip. The analysis of 142 136 autosomal single nucleotide polymorphisms (SNPs) revealed an Immunochip‐wide significant signal (PImmunochip = 7.01 × 10–9) for the SNP rs2075650 in the TOMM40/APOE region, which has been previously described in the context of human longevity. To identify novel susceptibility loci, we selected 15 markers with PImmunochip < 5 × 10–4 for replication in two samples from France (1257 LLI, mean age 102.4 years; 1811 controls, mean age 49.1 years) and Denmark (493 LLI, mean age 96.2 years; 740 controls, mean age 63.1 years). The association at SNP rs2706372 replicated in the French study collection and showed a similar trend in the Danish participants and was also significant in a meta‐analysis of the combined French and Danish data after adjusting for multiple testing. In a meta‐analysis of all three samples, rs2706372 reached a P‐value of PImmunochip+Repl = 5.42 × 10?7 (OR = 1.20; 95% CI = 1.12–1.28). SNP rs2706372 is located in the extended RAD50/IL13 region. RAD50 seems a plausible longevity candidate due to its involvement in DNA repair and inflammation. Further studies are needed to identify the functional variant(s) that predispose(s) to a long and healthy life. 相似文献
972.
973.
Multiple‐stressor effects on stream invertebrates: a mesocosm experiment manipulating nutrients,fine sediment and flow velocity
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Vasco Elbrecht Arne J. Beermann Gunnar Goessler Janis Neumann Ralph Tollrian Rüdiger Wagner Andre Wlecklik Florian Leese 《Freshwater Biology》2016,61(4):362-375
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974.
N. V. Zhukovskaya E. I. Bystrova V. B. Ivanov 《Russian Journal of Developmental Biology》2016,47(6):326-334
The lengths of meristematic (lm) and fully-elongated cells (le) were measured in the roots of 118 monocot and dicot species of herbaceous plants from 20 angiosperm families. The results were analyzed using the data on haploid DNA content (Cval) for the same species from the website (http://data.kew.org/cvalues). The distribution range of lm, le, and Cval was wider in monocot plants compared to dicots. Values of lm and le in monocot and lm in dicot species correlated positively with Cval. Dependence of lm and le on Cval was similar in diploid and polyploid species, both monocots and dicots. The average length of root cells differed less than the root length. 相似文献
975.
O.?M.?Ivanova R.?H.?ZiganshinEmail author G.?P.?Arapidi S.?I.?Kovalchuk I.?V.?Azarkin A.?V.?Sorokina V.?M.?Govorun V.?E.?Radzinsky V.?T.?Ivanov 《Russian Journal of Bioorganic Chemistry》2016,42(5):497-505
Serum samples (33 healthy women, 34 ovarian cancer, 28 colorectal cancer, 34 syphilis patients and 136 patients with various benign gynecological diseases) were analyzed by MALDI-TOF MS peptide profiling and respective predictive models were generated by genetic and supervised neural network algorithms. Classification models for pathology versus healthy control showed up to 100% sensitivity and specificity for all target diseases. However, the specificity dropped to unsatisfactory 25–40% in case of target versus nontarget disease diagnostics. Expansion of the control group to an artificial “nominal control” group by adding profiles of benign gynecological diseases considerably improved specificity of the models distinguishing ovarian cancer from healthy control and benign gynecological diseases. The suggested version of MALDI-TOF MS profiling of sera could be applied to differentiate between cancers and benign neoplasms of the same localization which is a challenging task for classical methods. To increase the specificity of diagnostic methods based on peptidome analysis of blood samples, it is necessary to identify sets of concrete peptide structures which qualitatively or quantitatively differ among patients with different diseases. 相似文献
976.
977.
Vassilis Daioglou Elke Stehfest Birka Wicke Andre Faaij Detlef P. van Vuuren 《Global Change Biology Bioenergy》2016,8(2):456-470
By‐products of agricultural and forestry processes, known as residues, may act as a primary source of renewable energy. Studies assessing the availability of this resource offer little insight on the drivers and constraints of the available potential as well as the associated costs and how these may vary across scenarios. This study projects long‐term global supply curves of the available potential using consistent scenarios of agriculture and forestry production, livestock production and fuel use from the spatially explicit integrated assessment model IMAGE. In the projections, residue production is related to agricultural and forestry production and intensification, and the limiting effect of ecological and alternative uses of residues are accounted for. Depending on the scenario, theoretical potential is projected to increase from approximately 120 EJ yr?1 today to 140–170 EJ yr?1 by 2100, coming mostly from agricultural production. To maintain ecological functions approximately 40% is required to remain in the field, and a further 20–30% is diverted towards alternative uses. Of the remaining potential (approximately 50 EJ yr?1 in 2100), more than 90% is available at costs <10By‐products of agricultural and forestry processes, known as residues, may act as a primary source of renewable energy. Studies assessing the availability of this resource offer little insight on the drivers and constraints of the available potential as well as the associated costs and how these may vary across scenarios. This study projects long‐term global supply curves of the available potential using consistent scenarios of agriculture and forestry production, livestock production and fuel use from the spatially explicit integrated assessment model IMAGE. In the projections, residue production is related to agricultural and forestry production and intensification, and the limiting effect of ecological and alternative uses of residues are accounted for. Depending on the scenario, theoretical potential is projected to increase from approximately 120 EJ yr?1 today to 140–170 EJ yr?1 by 2100, coming mostly from agricultural production. To maintain ecological functions approximately 40% is required to remain in the field, and a further 20–30% is diverted towards alternative uses. Of the remaining potential (approximately 50 EJ yr?1 in 2100), more than 90% is available at costs <10$2005 GJ?1. Crop yield improvements increase residue productivity, albeit at a lower rate. The consequent decrease in agricultural land results in a lower requirement of residues for erosion control. The theoretical potential is most sensitive to baseline projections of agriculture and forestry demand; however, this does not necessarily affect the available potential which is relatively constant across scenarios. The most important limiting factors are the alternative uses. Asia and North America account for two‐thirds of the available potential due to the production of crops with high residue yields and socioeconomic conditions which limit alternative uses. 相似文献
978.
Angeliki M. Nikolakopoulou Jordan Koeppen Michael Garcia Joshua Leish Andre Obenaus Iryna M. Ethell 《ASN neuro》2016,8(1)
Traumatic brain injury (TBI) can result in tissue alterations distant from the site of the initial injury, which can trigger pathological changes within hippocampal circuits and are thought to contribute to long-term cognitive and neuropsychological impairments. However, our understanding of secondary injury mechanisms is limited. Astrocytes play an important role in brain repair after injury and astrocyte-mediated mechanisms that are implicated in synapse development are likely important in injury-induced synapse remodeling. Our studies suggest a new role of ephrin-B1, which is known to regulate synapse development in neurons, in astrocyte-mediated synapse remodeling following TBI. Indeed, we observed a transient upregulation of ephrin-B1 immunoreactivity in hippocampal astrocytes following moderate controlled cortical impact model of TBI. The upregulation of ephrin-B1 levels in hippocampal astrocytes coincided with a decline in the number of vGlut1-positive glutamatergic input to CA1 neurons at 3 days post injury even in the absence of hippocampal neuron loss. In contrast, tamoxifen-induced ablation of ephrin-B1 from adult astrocytes in ephrin-B1loxP/yERT2-CreGFAP mice accelerated the recovery of vGlut1-positive glutamatergic input to CA1 neurons after TBI. Finally, our studies suggest that astrocytic ephrin-B1 may play an active role in injury-induced synapse remodeling through the activation of STAT3-mediated signaling in astrocytes. TBI-induced upregulation of STAT3 phosphorylation within the hippocampus was suppressed by astrocyte-specific ablation of ephrin-B1 in vivo, whereas the activation of ephrin-B1 in astrocytes triggered an increase in STAT3 phosphorylation in vitro. Thus, regulation of ephrin-B1 signaling in astrocytes may provide new therapeutic opportunities to aid functional recovery after TBI. 相似文献
979.
Salome Jones Renzo Perissinotto Nicola Kim Carrasco Andre Vosloo 《Marine Biology Research》2016,12(2):158-167
Shallow coastal lakes are prone to large fluctuations in physico-chemical variables such as salinity and turbidity. This is now escalating in response to global change. A flood event in March 2014 resulted in a silt plume spreading through part of Lake St Lucia (South Africa). To determine the impact of this event on zooplankton, the Narrows region of St Lucia was sampled on a monthly basis from March to September 2014. For comparative purposes, data from samples collected prior to the flood event were included in the analyses. Analysis of similarity (ANOSIM) revealed dissimilarities in zooplankton community structure among the sampling occasions. The March 2014–May 2014 period was characterized by the highest abundance of freshwater species. Conversely, the abundance of the resident St Lucia copepods Acartiella natalensis and Oithona brevicornis was lowest during this time, and highest in September 2014. The other dominant copepod Pseudodiaptomus stuhlmanni prevailed in March 2014, but declined markedly in April. As of September 2014, P. stuhlmanni had yet to regain its pre-flood densities. The BIOENV procedure, which relates biological and environmental data, revealed that turbidity, salinity and dissolved oxygen were responsible for the observed changes in zooplankton community structure during the study period. Careful management of turbidity and salinity is stressed, as both factors are major drivers of the biota of St Lucia and similar systems worldwide. 相似文献
980.