Variation in chromosome numbers and nuclear DNA contents in genetic resources of Lactuca L. species (Asteraceae)     

Ivana Doležalová  Aleš Lebeda  Josef Janeček  Jarmila Číhalíková  Eva Křístková  Olga Vránová 《Genetic Resources and Crop Evolution》2002,49(4):385-397

Fifty accessions of 25 Lactuca species,L. serriola ×L. sativa and Mycelismuralis were analyzed for chromosome number and relative DNA amountvariation. In the majority of Lactuca species studiedchromosome counts, as earlier reported (n = 8, 9, 17), were verified; however,for L. dregeana andL. homblei (probablyL. schweinfurthii orL. longespicata) the chromosome number(n = 9) was determined for the first time. Relative nuclear DNA content,estimated by using flow cytometry (DAPI staining), showed that 2C DNA contentranged from 2.02 pg in L.capensis to 17.96 pg inL. canadensis. Statistical and clusteranalysis of data based on relative nuclear DNA contents correspond fairly wellwith recently accepted taxonomic classification of the genusLactuca. However, the position of certain species as wellas clarification of taxonomic determinations of someLactuca accessions needs further examination.  相似文献   

The effect of pH and atmospheric deposition on concentrations of trace elements in acidified freshwaters: A statistical approach     

Josef Veselý  Vladimír Majer 《Water, air, and soil pollution》1996,88(3-4):227-246

A statistical evaluation of 5 338 analysis of freshwaters from little polluted stream basins in the Czech Republic indicated a relationship between the Pb, Cu, Zn, Cd, Be, As, Mn, Sr, F^? and Fe concentrations and the pH, over a range of pH 3.6 to 9.6. Except for Sr, the median concentrations of all the trace metals increase with decreasing pH, but the increase never extends over the whole studied acidic range (pH 3.6 to 7.0). Acid deposition related mobilization of Mn and Be into freshwaters explains the sharp increase in their concentrations with decreasing pH. Cadmium and Zn are also mobilized n strongly acidic environment. The concentrations of Be, As, F^? and Mn in strongly acidic waters and those of Zn and Cd in weakly acidic ones are considerably higher in areas receiving a higher atmospheric loading. For Be and Mn, the higher concentrations are caused by higher acid deposition rates, while for As and F^?, the concentrations are probably greater due to higher atmospheric deposition of these elements over more intensely acontaminated areas of the Czech Republic. In extremely acidic waters (pH < 4.2), the concentrations of Mn, Be, Cd, Zn and Al no longer increase with decreasing pH; on the contrary, those of Mn and Be actually decrease. This seems to be primarily caused by a decrease in their concentrations within the surface horizons of soils and vegetation induced by prolonged leaching. The Cd and Zn concentrations are independent of pH over an interval of pH 5.4 to 6.0 and thus the increase in the mean concentrations of Cd and Zn with decreasing pH involves two separate stages, at pH > 6.0 and at pH < 5.4. The concentrations of Cu in acid freshwaters are controlled by both the presence of high molecular weight organics plus biota uptake and by their atmospheric deposition levels; the concentrations of As and Pb are in addition controlled by sorption on Fe - oxyhydroxides. These elements accumulate in the topsoil, even under conditions of severe acidification. The surprisingly lower concentrations of Pb and Cu were found in acidic waters of more contaminated areas.  相似文献   

Cloning and molecular analysis of the regulatory factor HlMyb1 in hop (Humulus lupulus L.) and the potential of hop to produce bioactive prenylated flavonoids     

Matousek J  Vrba L  Novák P  Patzak J  De Keukeleire J  Skopek J  Heyerick A  Roldán-Ruiz I  De Keukeleire D 《Journal of agricultural and food chemistry》2005,53(12):4793-4798

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Characterization of sulfur speciation in low molecular weight subunits of glutenin after reoxidation with potassium iodate and potassium bromate at different pH values using x-ray absorption near-edge structure (XANES) spectroscopy     

Prange A  Birzele B  Krämer J  Modrow H  Chauvistré R  Hormes J  Köhler P 《Journal of agricultural and food chemistry》2003,51(25):7431-7438

Sulfur speciation in low molecular weight (LMW) subunits of glutenin after reoxidation with potassium iodate and potassium bromate at different pH values, aged subunits of glutenin as well as gluten, and gliadin have been investigated in situ by S K-edge X-ray absorption near-edge structure (XANES) spectroscopy. XANES spectra were analyzed quantitatively using a least-squares fitting routine to provide relative percentage contribution of different sulfur species occurring in the samples. Using potassium iodate and potassium bromate for reoxidation of reduced LMW subunits of glutenin led not only to disulfide states but also to higher oxidation states (sulfoxide state, sulfonic acid state). Strongest oxidation occurred at low pH values. Higher oxidation states were also predominantly detected in the aged subunits of glutenin, whereas the disulfide state was the main sulfur species in gluten and gliadin samples. The results showed that the oxidation state of sulfur prior to oxidation (thiol, disulfide) strongly influences sulfur speciation after oxidation. The choice of the oxidizing reagent seems to be of minor importance.  相似文献   

Plasma cholesterol levels and short-term adaptations of metabolism and milk production during feed restriction in early lactating dairy cows on pasture     

Josef J. Gross  Ann-Catherine Schwinn  Esther Müller  Andreas Münger  Frigga Dohme-Meier  Rupert M. Bruckmaier 《Journal of animal physiology and animal nutrition》2021,105(6):1024-1033

Low plasma total cholesterol (TC) concentrations are characteristic during the negative energy balance in early lactating dairy cows. The objective was to investigate short-term effects of different TC concentrations during an aggravated energy deficiency through a 1-week concentrate withdrawal on adaptations of metabolism and milk production. Multiparous Holstein cows (n = 15) were investigated during 3 week beginning at 24 ± 7 DIM (mean ± SD). Cows were kept on pasture and received additional concentrate in experimental week 1 and 3, while in week 2, concentrate was withdrawn. Blood was sampled once and milk twice daily. Based on their average TC concentration during week 1 (prior to concentrate withdrawal), cows were retrospectively assigned into a high (H-Chol; n = 8, TC ≥ 3.36 mmol/L) and a low TC groups (L-Chol; n = 7, TC < 3.36 mmol/L). Concentrations of phospholipids and lipoproteins were higher in H-Chol compared to L-Chol throughout the study (p < 0.05). During concentrate withdrawal, milk yield, glucose and insulin concentrations decreased similarly in both groups, while milk fat, milk acetone and plasma BHB were higher in H-Chol compared to L-Chol (p < 0.05). Compared to initial values, plasma NEFA, TAG and VLDL increased in both groups within 2 days after concentrate withdrawal (p < 0.05). Concentrations of NEFA during week 2 were greater in L-Chol compared to H-Chol (p < 0.05). Despite reintroduction of concentrate, milk yield in H-Chol remained lower for two more days compared to week 1 (p < .05), whereas milk yield recovered immediately in L-Chol. Activity of aspartate aminotransferase was higher in H-Chol compared to L-Chol in week 2 (p < 0.05). Greater plasma TC concentrations were associated with a reduced increase of NEFA. Further research is warranted if TC concentrations are related to adipose tissue mobilization and fatty acid turnover.  相似文献   

Potential Nitrate Leaching Under Common Landscaping Plants     

José A. Amador  Richard J. Hull  Erika L. Patenaude  John T. Bushoven  Josef H. Görres 《Water, air, and soil pollution》2007,184(1-4):323-333

Two Elsholtzia haichowensis S. populations, copper-tolerant (TLS) and non-tolerant (HA) ones were studied in hydroponic experiment for the nitrogen assimilation and plant growth under excess Cu conditions. The results demonstrated that there were surely the differences in nitrogen assimilation and plant growth between the two populations. Excess Cu caused evident decreases in the shoot and root biomass and root/shoot biomass ratio in HA population while no significant changes happened in TLS population. In addition, in HA population, excess Cu also induced apparent declines in activities of nitrate reductase (NR, EC 1.6.6.1) and glutamine synthetase (GS, EC 6.3.1.2) in the leaves and roots as well as the contents of nitrate, ammonium and amino acids in the roots. In TLS population, excess Cu did not significantly affect the NR activities in the leaves and roots and the nitrate content in the roots, and apparently elevated the root ammonium and amino acids contents, although it also clearly reduced the GS activities in the leaves and roots. Besides, with the addition of Cu in the culture solution, the Cu contents in the leaves and roots of the two populations markedly increased. But this increase was significantly lower in TLS population than that in HA population; the fact might be partly responsible for the relative stabilization of nitrogen assimilation in TLS population compared to that in HA population.  相似文献   

Monoclonal Gammopathy Associated With Naturally Occurring Canine Ehrlichiosis   总被引：1，自引：0，他引：1  

Edward B. Breitschwerdt DVM    Benny J. Woody DVM    Carole A. Zerbe DVM    Edward V. De  Buysscher DVM  PhD Ota Barta MVDr  PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1987,1(1):2-9

Clinical, hematologic, and immunologic findings for 14 dogs with Ehrlichia canis monoclonal gammopathy were studied retrospectively. Epistaxis, anemia, thrombocytopenia, hypoalbuminemia, hypergammaglobulinemia, and proteinuria were documented in the majority of these dogs. The serum protein electrophoresis pattern was characterized by a distinct narrow-base monoclonal spike, by a broad-base monoclonal spike, or by a monoclonal spike superimposed on a polyclonal gammopathy. The monoclonal spike disappeared following tetracycline treatment for ehrlichiosis. The long-term prognosis following treatment was generally good. The diagnostic features of monoclonal gammopathy due to myeloma were compared with those of E. canis monoclonal gammopathy. Owing to numerous similarities in clinical, hematologic, and immunologic findings, we conclude that an E. canis antibody titer should be determined in all dogs in which a diagnosis of benign monoclonal gammopathy is contemplated or definitive evidence of myeloma, leukemia, or macroglobulinemia is lacking.  相似文献   

Butterfly dispersal in inhospitable matrix: rare,risky, but long-distance   总被引：1，自引：1，他引：0  

Piotr Nowicki  Vladimir Vrabec  Birgit Binzenhöfer  Johann Feil  Barbara Zakšek  Thomas Hovestadt  Josef Settele 《Landscape Ecology》2014,29(3):401-412

Metapopulation models typically assume that suitable habitats occupied by local populations and unsuitable matrix separating them form a ‘black-and-white’ landscape mosaic, in which dispersal is primarily determined by the spatial configuration of habitat patches. In reality, however, the matrix composition is also likely to influence dispersal. Using intensive mark-recapture surveys we investigated inter-patch movements in Maculinea (Phengaris) nausithous and M. teleius occurring sympatrically in six metapopulations. Three of these metapopulations had the matrix dominated by forest, an inhospitable environment for grassland butterflies, whereas in the remaining three the matrix was mostly composed of open environments. Dispersal parameters derived with the Virtual Migration model revealed significant differences between both groups of metapopulations. Both species had a lower propensity to emigrate from their natal habitat patches, and they suffered substantially higher dispersal mortality in the metapopulations with forest matrix. On the other hand, mean dispersal distances were roughly an order of magnitude longer in forest matrix as compared with open landscapes (ca. 500–1,500 vs. 100–200 m). Our results suggest that inhospitable forest matrix induces strong selection against dispersal, leading to a reduced emigration rate. At the same time, the selection may promote emigrants with good dispersal abilities, which are able to perform long-distance movements. Thus, while it is generally believed that a matrix structurally similar to the habitat of a species should improve the functional connectivity of habitat patches, our findings imply that this may not necessarily be the case.  相似文献   

Vitrification of fully grown and growing porcine oocytes using germinal vesicle transfer     

Nakagawa S  Maedomari N  Kikuchi K  Nagai T  Miyano T  Fulka J  Manabe N 《The Journal of reproduction and development》2011,57(3):335-341

The survival rate of vitrified germinal vesicle (GV) stage porcine oocytes is very low, and it is not known if the vitrification damages the nucleus, cytoplasm or both. We have evaluated the eventual GV or cytoplasmic damage in fully grown (FG) and growing vitrified oocytes. Fifty-five percent of nonvitrified FG cumulus-denuded oocytes reached the metaphase II (MII) stage in culture. When growing oocytes from preantral (PA) and early antral (EA) follicles were matured in vitro, almost all oocytes were arrested at the GV stage (GV stage: PA 88.9 and EA 79.5%, respectively). When fresh GVs from FG, PA and EA oocytes were transferred into fresh enucleated FG oocytes and matured in vitro, some of them reached the MII stage (MII stage: FG/FG 57.5%, PA/FG 9.3% and EA/FG 35.3%, respectively). The maturation rate of vitrified FG oocytes was only 6.1% but increased dramatically when vitrified GVs from FG, PA and EA oocytes were transferred into fresh enucleated FG oocytes (MII stage: VitFG/FG 43.9%, VitPA/FG 7.1% and VitEA/FG 26.3%, respectively). These results were not significantly different from those for the nonvitrified groups (MII stage: FG/FG 57.5%, PA/FG 9.3% and EA/FG 35.3%, respectively). We activated the reconstructed oocytes that received fresh or vitrified GVs (FG/FG, EA/FG, VitFG/FG and VitEA/FG) and examined their embryonic development. Cleaved embryos (nonvitrified groups 13.0-61.8%, vitrified groups 33.3-40.0%) and blastocysts (nonvitrified groups 0.0-18.2%, vitrified groups 0.0-2.9%) were obtained after activation. These results demonstrate that vitrified porcine GVs maintain maturational and developmental competence and that vitrification predominantly damages the cytoplasm.  相似文献   

A spatial assessment of Culicoides spp. distribution and bluetongue disease risk areas in Austria     

Silbermayr K  Hackländer K  Doscher C  Koefer J  Fuchs K 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(5-6):228-235

Bluetongue disease (BT) was introduced into Central Europe in the summer of 2006 and has since affected most European countries. In this study we analysed the distribution of the biting midge vector Culicoides spp. in Austria and modelled Bluetongue disease risk zones. Culicoides spp. abundance data was collected from weekly catches of 14 months from 54 trapping locations. The corresponding weather data mean temperature (p < 0.001), wind (p < 0.001), relative humidity (p = 0.019) and altitude (p = 0.059) were identified as predictors on Culicoides spp. distribution in a regression model (R 2.8.0). The majority of catches were detected at temperatures above 10 degrees C and at relative humidities between 65-80%. The point data of these parameters originating from 186 meteorological stations were interpolated using the Geostatistical Analyst Kriging tool (ESRI ArcGIS 9.3). To create seasonal risk maps we overlaid regions with optimal temperature and humidity conditions with domestic ruminants density data. Our results show that the summer season holds the greatest risk of a BT epidemic with 25.9% of the analysed area providing optimal conditions for vector abundance and 12.4% showing contact risk with ruminant hosts. This project (1) provides fundamental data on the Culicoides spp. distribution in Austria, (2) determines limiting climatic parameters on vector abundance and (3) identifies risk areas by including areas of possible host-parasite-interactions. These high-risk areas can subsequently be given special attention for precautionary monitoring and surveillance measures.  相似文献