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991.
992.
Paweł Wiśniewski Justyna Szklarczyk Marcin Maciaga Andrzej Paszkowski 《Acta Physiologiae Plantarum》2006,28(6):577-588
The occurrence of four l-alanine:2-oxoglutarate aminotransferase (AOAT) isoenzymes (AOAT-like proteins): alanine aminotransferase 1 and 2 (AlaAT1
and AlaAT2, EC 2.6.1.2) and l-glutamate:glyoxylate aminotransferase 1 and 2 (GGAT1 and GGAT2, EC 2.6.1.4) was demonstrated in Arabidopsis thaliana leaves. These enzymes differed in their substrate specificity, susceptibility to pyridoxal phosphate inhibitors and behaviour
during molecular sieving on Zorbax SE-250 column. A difference was observed in the electrostatic charge values at pH 9.1 between
GGAT1 and GGAT2 as well as between AlaAT1 and AlaAT2, despite high levels of amino acid sequence identity (93 % and 85 %,
respectively). The unprecedented evidence for the monomeric structure of both AlaAT1 and AlaAT2 is presented. The molecular
mass of each enzyme estimated by molecular sieving on Sephadex G-150 and Zorbax SE-250 columns and SDS/PAGE was approximately
60 kDa. The kinetic parameters: Km (Ala)=1.53 mM, Km (2-oxoglutarate)=0.18 mM, kcat=124.6 s−1, kcat/Km=8.1 × 104 M−1·s−1 of AlaAT1 were comparable to those determined for other AlaATs isolated from different sources. The two studied GGATs also
consisted of a single subunit with molecular mass of 47.3–70 kDa. The estimated Km values for l-glutamate (1.2 mM) and glyoxylate (0.42 mM) in the transamination catalyzed by putative GGAT1 contributed to indentification
of the enzyme. Based on these results we concluded that each of four AOAT genes in Arabidopsis thaliana leaves expresses different AOAT isoenzyme, functioning in a native state as a monomer. 相似文献
993.
994.
Jacek Wendykier Aleksandra Grzdziel Barbara Bekman Marcin Bieniasiewicz Adam Bekman Piotr Wendykier Boena Wo
niak Marta Reudelsdorf Krzysztof
losarek 《Reports of Practical Oncology and Radiotherapy》2021,26(4):553
BackgroundThe comparison between profiles during the commissioning of the treatment planning system is an essential procedure. It is impossible to designate a field size for off-axis, wedged, and FFF beams directly by using the definition of the on-axis symmetric field size. This work proposes the use of different characteristic points as indicators of the field size for commissioning and QA purposes. This work aimed to search for the beam profile’s characteristic points and use them for the TPS commissioning purposes.Materials and methodsThe proposal is to use profile inflection points as the beam profile characteristic points. The usage of dedicated software allowed for comparing distances between inflection points and between points of 50% intensity. For the off-axis, wedged, and FFF fields, comparisons were made to the nominal field sizes.ResultsDistances between inflection points proved to be different by less than 1 mm from nominal field sizes for all kinds of investigated beams.ConclusionsInflection points are convenient for comparing the off-axis, wedged, and FFF field sizes because of their independence from profile normalization. With finite accuracy, the inflection points could be used for the above kind of beam sizes designation. 相似文献
995.
The present study was designed to find out whether brain nitric oxide (NO) influences hemodynamic response to intracerebroventricular (ICV) infusion of interleukin-1 beta (IL-1beta). Mean arterial blood pressure (MAP) and heart rate (HR) were recorded in seven series of experiments performed on conscious Sprague-Dawley rats receiving during 60 min ICV infusion of: 0.9% NaCl (5 microl/h; series 1), IL-1beta (100 ng/h; series 2), NO synthase inhibitor (L-NAME, 1mg/h; series 3), IL-1beta together with L-NAME (series 4), IL-1beta together with inactive isomer of NO synthase inhibitor (D-NAME, 1mg/h; series 5), NO donor (SNAP, 40 microg/h; series 6) and IL-1beta together with SNAP (series 7). ICV infusion of saline did not influence MAP while administration of IL-1beta as well as IL-1beta together with D-NAME elicited a significant, though transient, increase in MAP. In series 4, combined infusion of IL-1beta and L-NAME exerted an increase in MAP, which persisted until the end of the experiment and was significantly higher than in series 2 and 5. In series 7, infusion of SNAP together with IL-1beta abolished the pressor effect of IL-1beta. HR was not significantly altered in any of the experimental series. These results demonstrate that inhibition of NO synthesis in the brain enhances and prolongs the pressor response to IL-1beta, whereas concomitant administration of NO donor abolishes the hemodynamic effect of IL-1beta. Therefore, we conclude that NO generated in the brain is involved in buffering the pressor response to IL-1beta. 相似文献
996.
Probiotic utilization is becoming increasingly popular in veterinary medicine. However, only few probiotic products are available commercially for use in dogs in our market. Therefore, the aim of our study was to determine the properties of new potential probiotic Lactobacillus fermentum AD1 strain-own canine isolate and to investigate its effect on several microbiological and biochemical parameters in healthy dogs. The strain expressed in vitro survival by pH 3.0 after 3h (86.8%) and in the presence of 1% bile (75.4%). The AD1 strain adhered to the canine and human intestinal mucus. It was sensitive to commonly used antimicrobials. Fifteen healthy dogs were supplemented with 10(9)L. fermentum AD1 for 7 days. At the end of AD1 strain application, numbers of faecal lactobacilli and enterococci increased significantly in the canine faeces. Significant increase of total protein and total lipid and significant reduction of glucose in serum of dogs were noted. These data indicate that L. fermentum AD1 survive transit through the canine gastrointestinal tract, and populate the colon and probably increased absorption of some nutrients. Whether longer time of its application lead to the same results as well as its potential to improve immune function in dogs remains to be determined. 相似文献
997.
Doroszuk A Wojewodzic MW Kammenga JE 《Proceedings. Biological sciences / The Royal Society》2006,273(1601):2611-2618
Sexual reproduction is acknowledged to facilitate adaptation to novel environments while asexual eukaryotes are often regarded as having low adaptive potential. This view has been challenged in a number of studies, but the adaptive potential of asexual populations in the field is poorly documented. We investigated the response of natural populations of the parthenogenetic nematode Acrobeloides nanus to imposed divergent selective pressures. For this purpose, we employed a replicated evolution experiment in the field. After 20 years of evolution under abiotic stress and control conditions, life-history traits were assessed in reaction norm- and reciprocal transplant experiments. Both these experiments indicated adaptive divergence within the population of A. nanus. Namely, the transplant experiment demonstrated that in the stressed soil environment, body growth rate was more reduced in the nematodes originating from the control treatment. In the reaction norm experiment, survival and reproduction were higher under test conditions corresponding to the native environment of the nematodes. The differences in the analysed traits are discussed in the context of life-history theory. Overall, our results strongly support high adaptive potential of A. nanus and suggest that population structure and distribution of asexual species is shaped by local adaptation events. 相似文献
998.
Magdalena Jaszek Jerzy uchowski Elbieta Dajczak Kamila Cimek Marcin Graz Krzysztof Grzywnowicz 《International biodeterioration & biodegradation》2006,58(3-4):168
The effect of menadione (MQ; 2-methyl-1,4-naphtoquinone) superoxide generating agent on the biological activity of two strains of white-rot fungi, Fomes fomentarius and Tyromyces pubescens, was determined. In this study 1 mM of MQ solution was added to 10-day-old idiophasic cultures. The application of MQ to F. fomentarius and T. pubescens cultures stimulated extracellular laccase (LAC) and manganese-dependent peroxidase (MnP) activities in comparison to the control values (without MQ). In the presence of MQ the concentration of oxalic acid in the medium of both fungi was dramatically decreased. MQ treatment also caused an increase of intracellular superoxide dismutase activity, formaldehyde and glutathione disulfide level in both strains. In the case of F. fomentarius, addition of MQ enhanced catalase activity. The rate of intra- and extracellular proteolysis decreased in F. fomentarius and increased in T. pubescens MQ treated cultures. 相似文献
999.
Research was carried out to determine aquatic oligochaete habitat preferences in the Rokytná River (Thaya River basin), a
sixth order highland stream in the Czech Republic during the period of April 1999–April 2001. Quantitative samples were collected
and current velocity and basic physico-chemical variables were measured monthly in four typical habitats in the Rokytná River.
During this study, 28, 842 individuals representing 44 oligochaete species or higher taxa were collected. Temporal variability
of proportional occurrence of trophic groups found on selected habitats (gathering collectors and grazers) was analysed. Habitat
preferences of oligochaete species were evaluated by Canonical Correspondence Analysis (CANOCO). Biochemical oxygen demand
(BOD) and nitrate (NO3−) ion concentration were the most important variables explaining the distribution of Oligochaeta along the first axis. Current
velocity (at 40% of the depth) and presence of oligochaetes associated with the habitat where gravel bars never formed were
the most important variables along the second axis. Both axes were correlated with the temperature, reflecting the sampling
in summer along the first axis and sampling in late spring along the second axis. The amount of organic matter (BOD) and concentrations
of NO3− ions represented both oligochaete food source and decomposition products contributing to the growth of algae. Current velocity
and preferred habitat explained the spatial pattern of oligochaete distributions. 相似文献
1000.
The early medical complications of Chernobyl accident include post radiation disease, which were diagnosed in 134 subjects affected by ionizing radiation. 28 persons died during the first 100 days after the event. The increase occurrence of coronary heart disease, endocrine, haematological, dermatological and other diseases were observed after disaster in the contaminated territories. We also discussed the impact of ionizing radiation from Chernobyl accident on pregnancy and congenital defects occurrence. Changes following the Chernobyl accident, as the inhabitants migration from contaminated regions, political and economic conversions, led to depression, anxiety, and even to "epidemic" of mental diseases. Increased suicide rate, car accidents, alcohol and drug abuse have been observed in this population. Nowadays vegetative neurosis is more often diagnosed in Ukrainian children. Epidemiological studies were conducted on the ionising radiation effect on the health and on the dose of received radiation after Chernobyl accident face numerous problems as the absence of reliable data regarding diseases in the contaminated territories. 相似文献