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51.
Stachowska E Dziedziejko V Safranow K Jakubowska K Olszewska M Machaliñski B Chlubek D 《Journal of agricultural and food chemistry》2007,55(13):5335-5342
Lipoxygenases are a family of non-heme enzyme dioxygenases. The role of lipoxygenases is synthesis of hydroperoxides of fatty acids, which perform signaling functions in the body. Studies on conjugated linoleic acids (CLAs) as fatty acids with a potential anti-atherosclerotic function have recently been initiated. The aim of the study was to test the effect of CLAs and linoleic acid on 5- and 15-lipoxygenase (5-LO, 15-LO-1) enzyme activity, their mRNA expression, and concentration in the cells. It was also desired to determine whether the CLAs are substrates for the enzymes. For the experiments monocytic cell line (THP-1) and monocytes obtained from human venous blood were used. Monocytes were differentiated to macrophages: THP-1 (CD14+) by PMA administration (100 nM for 24 h) and monocytes from blood (CD14+) by 7-day cultivation with the autologous serum (10%). After differentiation, macrophages were cultured with 30 microM CLAs or linoleic acid for 48 h. The 15- and 5-lipoxygenase products were measured by HPLC method. mRNA expression and protein content were analyzed by real-time PCR and Western blot analysis. The in vitro studies proved that both CLA isomers are not substrates for 15-LO-1; in ex vivo studies hydroxydecadienoic acid (HODE) concentration was significantly reduced (p = 0.019). The trans-10,cis-12 CLA isomer reduced HODE concentration by 28% (p = 0.046) and the cis-9,trans-11 CLA isomer by 35% (p = 0.028). In macrophages obtained from THP-1 fatty acids did not change significantly mRNA expression of the majority of the investigated genes. CLAs did not change the content of 5-LO and 15-LO-1 proteins in macrophages obtained from peripheral blood. Linoleic acid induced 15-LO-1 expression (2.6 times, p < 0.05). CLAs may perform the function of an inhibitor of lipoxygenase 15-LO-1 activity in macrophages. 相似文献
52.
Danuta Chołuj Ewa B. Moliszewska 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):59-70
Alterations in some physiological processes in source leaves of sugar beet—such as chlorophyll and carbohydrate concentrations,
stomatal conductance, rate of net photosynthesis and transpiration, and activity of the photosynthetic apparatus during root
interaction with Aphanomyces cochlioides, were investigated. The influence of time of infection on plant health, yield quality and quantity was also examined. Plants
were infected at different times of their growth period: on the sowing day and 4 or 8 weeks after sowing. A variation treatment,
with non-pelleted seeds infected on the sowing day, was also analyzed. The experiment showed that development of disease symptoms
depends on the time of infection and seed protection. A significant root yield decrease was observed in case of late infection,
as compared to the yield of plants infected on the sowing day. The fresh weight of leaves was significantly increased where
there was late infection. The infected plants showed a lower content of K+, Na+ and α-amino-N than did the controls. Infection by A. cochlioides induced chlorophyll degradation mostly in older leaves with the occurrence of natural senescence processes. Chlorophyll fluorescence
parameters indicated that the photosynthetic apparatus of younger leaves was more sensitive to pathogen infection, when compared
to older ones. The photochemical efficiency of photosystem II was reduced in young leaves mainly due to disturbance of the
water-splitting system. In plants grown from non-pelleted seeds a strong impairment of PSII was observed only in those leaves
which developed during early pathogen infection. In young leaves of plants infected in the fourth week after sowing, inhibition
of the rate of net photosynthesis was correlated with the increase in intercellular CO2 concentration, indicating some disturbance in the carbon assimilation phase. In mature leaves of late infected plants the
reduction of photosynthesis net rate was associated with a decrease of stomatal conductance and an increase of diffusion resistance
to CO2 and H2O, which was also the cause of the transpiration rate inhibition. When the leaves developed during early infection, an increase
of specific leaf weight and accumulation of carbohydrates was observed. In mature leaves of non-protected plants infected
on the sowing day, the recovery of all physiological processes was observed together with a diminution of disease symptoms. 相似文献
53.
The Forgotten Rural Landscapes of Central and Eastern Europe 总被引:1,自引:0,他引:1
Hannes Palang Anu Printsmann Éva Konkoly Gyuró Mimi Urbanc Ewa Skowronek Witold Woloszyn 《Landscape Ecology》2006,21(3):347-357
Interactions between nature and man – the underlying forces in landscape – have over time caused diversity. Usually, geographers
and landscape ecologists deal with spatial diversity; in this paper, we would like to also consider temporal diversity. We
argue that Central and Eastern European landscapes (using the examples of Estonia, Hungary, Poland and Slovenia) are much
more diverse in time (layers) than Western European ones. This difference requires the use of different indicators in order
to measure and study landscapes and special problems, threats, and possibilities of management and future development – but
most important is the consideration of different perceptions. We also show that this diversity reduces the readability of
landscapes, creating miscommunication and a transformation of meanings. We further argue that the link between humans and
landscape is lost in Central and Eastern European countries due to temporal diversity, and that this link will be created
anew in a globalizing world. To overcome alienation, we need slightly different classifications/typologies for each country
in this region, with the aim of a sound future management of cultural landscapes. 相似文献
54.
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56.
The concentrations of thyroxine (T4), 3,3',5-triiodothyronine (T3) and 3,3',5'-triiodothyronine (reverse T3; rT3) in thyroid gland tissue and serum of the fetal pig (n = 68) from day 39 to 113 of gestation were measured. Tracer quantities of iodothyronines, displaying the onset of thyroid hormone activity, were found in the thyroid tissue on day 39, i.e. before the appearance of a measurable quantity of iodothyronines in the serum. The T4 and T3 thyroidal content showed the first rise between days 56 and 76. Then, T3 was increasing sharply from day 92 till birth, while T4 content was decreasing from about day 76 to a low value between day 92 and 105, and then showing an increase shortly before birth. The rT3 content was the highest on day 39 and then it was steadily decreasing to reach a nadir on about day 76. Measurable amounts of thyroid hormones (TH) in the serum were observed not earlier than on day 46 of gestation. Near birth, the tissues of the pig fetus are in a milieu characterised by the highest blood TH concentrations. The serum to thyroid concentration ratio for rT3 and T4 was generally below 1.0 until the last trimester of gestation, when it was over 5.0 for rT3 and over 4.0 for T4. By contrast, the T3 serum to thyroid ratio was below 0.5 throughout the gestation. The results show that the fetal pig thyroid displays a low rT3 and T4 content, but the marked T3 elevation observed near term supports the view that a high production and secretion of T3 near term may be a critical factor for normal postnatal adaptation to extrauterine cooling in the pig. 相似文献
57.
Ewa Smolska 《CATENA》2007
The density of gully network in the Suwa?ki Lakeland (northeastern Poland) with typical last-glaciation relief is 0.2 km/km2 on average and locally reaches 1.2 km/km2. Most gullies are isolated but sporadically they create dendritic patterns. The larger gullies are developed along dellies (bowl-shaped, dry valleys) or melt-out valleys. The smaller and shorter gullies occur on the slopes of melt-out depressions and tunnel valleys. Ages of peat covered by fans at the mouths of larger gullies indicate that gully erosion started between 3520 ± 70 to 2240 ± 100 BP. Two different units build the fans and infilled the gullies. The older unit in the lower part of fans is up to 5 m thick, contains sand and gravel that generally originated from the bottom and bank erosion of the gullies and resembles alluvium. The younger unit, about 2–3 m thick, consists of colluvium. The fans at the mouths of smaller and shorter gullies are mainly built of colluvium. The maximal grain diameter in both units is similar, which testifies to a similar intensity of extreme rainfalls. The analysed sediments have different characteristics, which indicate that the source material and depositional changes are linked to forest clearance and farmland expansion starting in the 7th century AD and continuing in the Middle Ages. 相似文献
58.
Ewa Wieczorek-Olchawa Maria Niklinska Jacek Miedzobrodzki Barbara Plytycz 《Pedobiologia》2003,47(5-6):702-709
59.
Karl Hammer Ewa Skolimowska Helmut Knüpffer 《Genetic Resources and Crop Evolution》1987,35(2):135-177
Zusammenfassung Die Genbank in Gatersleben verfügt über eine umfangreiche Wildroggen-Kollektion, die für die Aufgaben der Züchtungsforschung und Züchtung zur Verfügung steht. Probleme der Erhaltung dieser Kollektion in der Genbank werden diskutiert. In diesem Zusammenhang wird das Reproduktionssystem besonders untersucht.Zur Dokumentation des Materials ist seine Identifikation notwendig. Daher wurde die GattungSecale revidiert. Neukombinationen werden fürS. strictum (Presl) Presl — subsp.kuprijanovii (Grossh.) Hammer, subsp.anatolicum (Boiss.) Hammer, subsp.ciliatoglume (Boiss.) Hammer, subsp.africanum (Stapf) Hammer — und fürS. cereale L. — subsp.afghanicum (Vav.) Hammer — vorgeschlagen. Zur Determination der Sippen wird ein Bestimmungsschlüssel publiziert.Entwicklungstendenzen innerhalb der Gattung werden aufgezeigt.
Herrn Prof. Dr. Dr. h. c. mult.H. Stubbe aus Anlaß der 85. Wiederkehr seines Geburtstages gewidmet.
Der Beitrag von E. S. entstand im Ergebnis eines Studienaufenthaltes zur Vorbereitung ihrer Dissertation 1986 in Gatersleben. 相似文献
Preliminary work on monographs of wild plant collections:Secale L
Summary The Gatersleben gene bank holds a large collection of wild rye available for the tasks of breeding research and plant breeding. Problems of maintaining this collection in the gene bank are discussed. In this connection the breeding system is especially studied.A proper identification of the material is a necessary prerequisite for its documentation. Therefore, the genusSecale was revised. New combinations are proposed forS. strictum (Presl) Presl — subsp.kuprijanovii (Grossh.) Hammer, subsp.anatolicum (Boiss.) Hammer, subsp.ciliatoglume (Boiss.) Hammer, subsp.africanum (Stapf) Hammer — and forS. cereale L. — subsp.afghanicum (Vav.) Hammer. Keys for the determination of species and subspecies are given.Evolutionary trends within the genus are demonstrated.
: Secale L
, . . . . Secale. . S. strictum (Presl) Presl — subsp.kuprijanovii (Grossh.) Hammer, subsp.anatolicum (Boiss.) Hammer, subsp.ciliatoglume (Boiss.) Hammer, subsp.africanum (Stapf) Hammer — S. cereale L. — subsp.afghanicum (Vav.) Hammer. . .
Herrn Prof. Dr. Dr. h. c. mult.H. Stubbe aus Anlaß der 85. Wiederkehr seines Geburtstages gewidmet.
Der Beitrag von E. S. entstand im Ergebnis eines Studienaufenthaltes zur Vorbereitung ihrer Dissertation 1986 in Gatersleben. 相似文献
60.
Staffan Åkerblom Erland Bååth Lage Bringmark Ewa Bringmark 《Biology and Fertility of Soils》2007,44(1):79-91
This study compared the toxic effects of adding chromium (Cr), zinc (Zn), lead (Pb), molybdenum (Mo), nickel (Ni), and cadmium
(Cd) at three dose levels to mor layer samples in laboratory experiments. Microbial activity in the form of soil respiration
was monitored for 64 days. At the end of the experimental period, the composition of the soil microbial community structure
was analysed by phospholipid fatty acid (PLFA) analysis. The metals added induced changes in the microbial community structure
and affected respiration negatively, indicating toxicity. The microbial community structure (principal component analysis
of the PLFA pattern) for all metals was significantly related to microbial activity (cumulative respiration), indicating intimate
links between microbial community structure and activity. The most striking result in this study was that the shift in the
microbial community because of metal stress was similar for all metals. Thus, the PLFA i16:0 increased most in relative abundance
in metal-polluted soils, followed by other PLFAs indicative of Gram-positive bacteria (10Me16:0, 10Me17:0, 10Me18:0, a17:0
and br18:0). The PLFA 16:1ω5 was consistently negatively affected by metal stress, as were the PLFAs 18:1, 18:1ω7 and 19:1a.
However, a significant separation between Cr- and Cd-polluted soils was observed in the response of the PLFA cy19:0, which
decreased in abundance with Cr stress, and increased with Cd stress. Furthermore, the PLFA 18:2w6, indicating fungi, only
increased with Cr and Zn stress. The effective doses of the metals, ranked with regard to background metal concentrations,
decreased in the order: Zn > Cr > Pb > Mo > Ni > Cd. We concluded that interpretation of results of microbial activity from
experiments of metal toxicity should include microbial structural patterns and background metal concentrations. 相似文献