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21.
Irena A. Pidek Helena Svitavská-Svobodová Willem O. van der Knaap Agnieszka M. Noryśkiewicz Anna Filbrandt-Czaja Bożena Noryśkiewicz Małgorzata Latałowa Marcelina Zimny Joanna Święta-Musznicka Elissaveta Bozilova Spassimir Tonkov Mariana Filipova-Marinova Anneli Poska Thomas Giesecke Aleksander Gikov 《Vegetation History and Archaeobotany》2010,19(4):259-270
Annual pollen-accumulation rates (PAR) of Fagus (beech) obtained within the framework of the Pollen Monitoring Programme (PMP) were analyzed in pollen traps along a N–S transect from the Baltic Sea to the Black Sea in different European vegetation units. The study regions are situated in the lowlands of northern Poland, the uplands of SE Poland, the Czech Krkono?e Mts, the Czech ?umava Mts, the Swiss Jura Mts, the Swiss Alps, the Bulgarian Rila Mts and the Bulgarian Strandzha Mts. Most time series are 10 or 11 years long, some are 5–16 years long. Inter-annual fluctuations in Fagus PAR were analyzed and compared with seed mast years. Years with high Fagus PAR and others with low Fagus PAR occurred most frequently in parallel within each region and often in two neighbouring regions. 2006 was exceptional as it had a very high Fagus sylvatica pollen deposition in all study regions and it was also a mast year. In Bulgaria, the trend in the 5 years of Fagus orientalis PAR in the Strandzha Mts differed from that of F. sylvatica PAR in the Rila Mts. Aiming at establishing the relationship between average Fagus PAR and tree cover, differences in Fagus PAR (averaged per pollen trap) were related in each region to the proportion of beech trees in the vegetation within 2 km of the pollen traps, the distance to the nearest pollinating Fagus tree, regional or local presence of beech forests, the degree of landscape openness, and the size of forest opening in which a trap is situated. Average Fagus PAR was found to track the regional abundance of beech trees in the vegetation, not the distance of the nearest Fagus tree. Regional occurrence of beech-dominated forests was reflected by a Fagus PAR of ca. 1,400 grains cm?2 year?1, local abundance very close to pollen traps by ca. 2,400 grains, small patches of forest with admixture of Fagus by ca. 170–220 grains, and scarcity or absence of Fagus by ca. 40 grains or less. 相似文献
22.
Heather S. Pardoe Thomas Giesecke Willem O. van der Knaap Helena Svitavská-Svobodová Eliso V. Kvavadze Sampson Panajiotidis Achilles Gerasimidis Irena A. Pidek Marcelina Zimny Joanna Święta-Musznicka Małgorzata Latałowa Agnieszka M. Noryśkiewicz Elissaveta Bozilova Spassimir Tonkov Mariana V. Filipova-Marinova Jacqueline F. N. van Leeuwen Laimdota Kalniņa 《Vegetation History and Archaeobotany》2010,19(4):271-283
This paper compares pollen spectra derived from modified Tauber traps and moss samples from a selection of woodland types from Bulgaria, the Czech Republic, Georgia, Greece, Poland, Switzerland and Wales. The study examines the representation of individual taxa in the two sampling media and aims to ascertain the duration of pollen deposition captured by a moss. The latter aim was pursued through the calculation of dissimilarity indexes to assess how many years of pollen deposited in a pollen trap yield percentage values that are most similar to those obtained from the moss. The results are broadly scattered; the majority of moss samples being most similar to several years of pollen deposition in the adjacent trap. For a selection of samples, a comparison of the pollen accumulation rate in pollen traps with the pollen concentration in the moss per unit surface indicates that the entrapment and/or preservation of individual pollen types in the moss differ from that in the pollen trap. A comparison of the proportion of different taxa in the moss with the pollen spectrum of 2 years of pollen deposition in the trap also revealed large differences. There is a tendency for bisaccate grains such as Pinus and Picea to have a higher representation in moss than in traps but there is considerable regional variation. The results indicate that pollen proportions from moss samples often represent the pollen deposition of one area over several years. However, bisaccate pollen grains tend to be over-represented in moss samples compared to both pollen traps and, potentially, lake sediments. 相似文献
23.
Verónica García-Alonso Cristina López-Vicario Esther Titos Eva Morán-Salvador Ana González-Périz Bibiana Rius Marcelina Párrizas Oliver Werz Vicente Arroyo Joan Clària 《The Journal of biological chemistry》2013,288(39):28230-28242
Peroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated nuclear receptor and a master regulator of adipogenesis. Microsomal prostaglandin E (PGE) synthase-1 (mPGES-1) is an inducible enzyme that couples with cyclooxygenase-2 for the biosynthesis of PGE2. In this study we demonstrate the existence of a coordinate functional interaction between PPARγ and mPGES-1 in controlling the process of pre-adipocyte differentiation in white adipose tissue (WAT). Adipocyte-specific PPARγ knock-out mice carrying an aP2 promoter-driven Cre recombinase transgene showed a blunted response to the adipogenic effects of a high fat diet. Pre-adipocytes from these knock-out mice showed loss of PPARγ and were resistant to rosiglitazone-induced WAT differentiation. In parallel, WAT from these mice showed increased expression of uncoupling protein 1, a mitochondrial enzyme that dissipates chemical energy as heat. Adipose tissue from mice lacking PPARγ also showed mPGES-1 up-regulation and increased PGE2 levels. In turn, PGE2 suppressed PPARγ expression and blocked rosiglitazone-induced pre-adipocyte differentiation toward white adipocytes while directly elevating uncoupling protein 1 expression and pre-adipocyte differentiation into mature beige/brite adipocytes. Consistently, pharmacological mPGES-1 inhibition directed pre-adipocyte differentiation toward white adipocytes while suppressing differentiation into beige/brite adipocytes. This browning effect was reproduced in knockdown experiments using a siRNA directed against mPGES-1. The effects of PGE2 on pre-adipocyte differentiation were not seen in mice lacking PPARγ in adipose tissue and were not mirrored by other eicosanoids (i.e. leukotriene B4). Taken together, these findings identify PGE2 as a key regulator of white-to-brown adipogenesis and suggest the existence of a coordinate regulation of adipogenesis between PPARγ and mPGES-1. 相似文献
24.
Malondialdehyde plasma concentration correlates with declarative and working memory in patients with recurrent depressive disorder 总被引:1,自引:0,他引:1
Talarowska M Gałecki P Maes M Gardner A Chamielec M Orzechowska A Bobińska K Kowalczyk E 《Molecular biology reports》2012,39(5):5359-5366
Oxidative stress has been implicated in the cognitive decline, especially in memory impairment. The purpose of this study
was to determine the concentration of malondialdehyde (MDA) in patients with recurrent depressive disorders (rDD) and to define
relationship between plasma levels of MDA and the cognitive performance. The study comprised 46 patients meeting criteria
for rDD. Cognitive function assessment was based on: The Trail Making Test , The Stroop Test, Verbal Fluency Test and Auditory-Verbal
Learning Test. The severity of depression symptoms was assessed using the Hamilton Depression Rating Scale (HDRS). Statistically
significant differences were found in the intensity of depression symptoms, measured by the HDRS on therapy onset versus the
examination results after 8 weeks of treatment (P < 0.001). Considering the 8-week pharmacotherapy period, rDD patients presented better outcomes in cognitive function tests.
There was no statistically significant correlation between plasma MDA levels, and the age, disease duration, number of previous
depressive episodes and the results in HDRS applied on admission and on discharge. Elevated levels of MDA adversely affected
the efficiency of visual-spatial and auditory-verbal working memory, short-term declarative memory and the delayed recall
declarative memory. 1. Higher concentration of plasma MDA in rDD patients is associated with the severity of depressive symptoms,
both at the beginning of antidepressants pharmacotherapy, and after 8 weeks of its duration. 2. Elevated levels of plasma
MDA are related to the impairment of visual-spatial and auditory-verbal working memory and short-term and delayed declarative
memory. 相似文献
25.
Maria Bernardete Cordeiro de Sousa Nívea Saldanha Xavier Hélderes Peregrino Alves da Silva Marcelina Souza de Oliveira Maria Emília Yamamoto 《Primates; journal of primatology》2001,42(1):57-66
Hand preference has been investigated in New World primates but the data obtained thus far are controversial. In this study
we investigated hand preference in common marmosets,Callithrix jacchus, during the execution of a reaching for food task. We used 46 adult common marmoset males (n=27) and females (n=19) from the Universidade of Rio Grande do Norte colony, both wild and captive-born. To test the hand preference we used
a device measuring 10 cm2, with a central hole 1 cm in diameter, to force the animal to use only one hand to reach for food on a food dish located
underneath. Each animal was tested 5 times and had to make a maximum of 20 successful attempts per session. A total of 100
successful attempts per animal and 4,600 successful attempts for all animals were recorded during the experiment. Latency
and duration of the sessions were measured and we found preference for the use of one of the hands in common marmoset individuals,
i.e. 45 of total of 46 animals used significantly more the right or the left hand when performing the task. However no bias
at the population level was found. Females born in captivity presented an increase in the duration of latency for the first
successful attempt and in the total duration of the test sessions. These findings might be indicating differences associated
with a natural tendency for females to be more selective and to spend more time exploring alimentary sources. Additionally,
captive-born females may have a constrain in developing cognitive abilities regarding foraging since they have food available
during most part of the time. 相似文献
26.
Although every organism shares some common features of replication, this process varies greatly among eukaryotic species. Current data show that mathematical models of the organization of origins based on possibility theory may be applied (and remain accurate) in every model organism i.e. from yeast to humans. The major differences lie within the dynamics of origin firing and the regulation mechanisms that have evolved to meet new challenges throughout the evolution of the organism. This article elaborates on the relations between chromatin structure, organization of origins, their firing times and the impact that these features can have on genome stability, showing both differences and parallels inside the eukaryotic domain. 相似文献
27.
Marcelina E. Kremser Małgorzata Przybyło Dorota Hoja-Łukowicz Ewa Pocheć Angela Amoresano Andrea Carpentieri Monika Bubka Anna Lityńska 《Biochimica et Biophysica Acta (BBA)/General Subjects》2008
It is well documented that glycan synthesis is altered in some pathological processes, including cancer. The most frequently observed alterations during tumourigenesis are extensive expression of β1,6-branched complex type N-glycans, the presence of poly-N-acetyllactosamine structures, and high sialylation of cell surface glycoproteins. This study investigated two integrins, α3β1 and αvβ3, whose expression is closely related to cancer progression. Their oligosaccharide structures in two metastatic melanoma cell lines (WM9, WM239) were analysed with the use of matrix-assisted laser desorption ionisation mass spectrometry. Both examined integrins possessed heavily sialylated and fucosylated glycans, with β1,6-branches and short polylactosamine chains. In WM9 cells, α3β1 integrin was more variously glycosylated than αvβ3; in WM239 cells the situation was the reverse. Functional studies (wound healing and ELISA integrin binding assays) revealed that the N-oligosaccharide component of the tested integrins influenced melanoma cell migration on vitronectin and α3β1 integrin binding to laminin-5. Additionally, more variously glycosylated integrins exerted a stronger influence on these parameters. To the best of our knowledge, this is the first report concerning structural characterisation of αvβ3 integrin glycans in melanoma or in any cancer cells. 相似文献
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Plant Cell, Tissue and Organ Culture (PCTOC) - Mineral nutrients are necessary for the growth and development of plants. Previous studies have concentrated mainly on silicon-accumulating plants,... 相似文献
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