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441.
Deletion/insertion polymorphism of the prion protein gene (<Emphasis Type="Italic">PRNP</Emphasis>) in Polish Holstein-Friesian cattle 总被引:1,自引:0,他引:1
Czarnik U Zabolewicz T Strychalski J Grzybowski G Bogusz M Walawski K 《Journal of applied genetics》2007,48(1):69-71
The aim of the present study was to identify the deletion/insertion polymorphism of the bovine prion protein gene (PRNP) within the promoter sequence (23 bp), intron 1 (12 bp) and 3’ untranslated region (14 bp). DNA was isolated from blood of
234 randomly tested Polish Holstein-Friesian cows and from semen of 47 sires used for artificial insemination (AI) in 2004.
No statistically significant differences were found in the frequency of genotypes and alleles between cows and breeding bulls
in the 3 analysed polymorphic sites within thePRNP gene. Only 3 haplotypes were identified in sires and 4 haplotypes in cows. 相似文献
442.
Cultures of Saccharomyces cerevisiae were subjected to the effect of PEF (pulse electric field) and a source of selenium. The culture period after which yeast cells were subjected to PEF treatment was optimized, as was the duration of the exposure. Optimization of the nutrient medium composition in S. cerevisiae cultures resulted in an over 1.8-fold increase in selenium accumulation with relation to cultures on the initial substrate. Optimization of the pH value and of culture duration resulted in selenium accumulation increase by approximately 78%. A significant correlation was found between the accumulation of selenium in yeast cells and its concentration in the culture substrate. The highest accumulation of selenium in the biomass of yeast, approx. 240 microg/g d.m., was obtained after 15-min exposure to PEF on a 20-h culture. An approx. 50% higher content of selenium in cells was recorded, as compared with the control culture without the application of PEF. 相似文献
443.
Lau C Borgmann S Maciejewska M Ngounou B Gründler P Schuhmann W 《Biosensors & bioelectronics》2007,22(12):3014-3020
Indirectly heated electrodes operating in a non-isothermal mode have been used as transducers for reagentless glucose biosensors. Pyrroloquinoline quinone-dependent soluble glucose dehydrogenase (PQQ-sGDH) was entrapped on the electrode surface within a redox hydrogel layer. Localized polymer film precipitation was invoked by electrochemically modulating the pH-value in the diffusion zone in front of the electrode. The resulting decrease in solubility of an anodic electrodeposition paint (EDP) functionalized with Osmium complexes leads to precipitation of the redox hydrogel concomitantly entrapping the enzyme. The resulting sensor architecture enables a fast electron transfer between enzyme and electrode surface. The glucose sensor was operated at pre-defined temperatures using a multiple current-pulse mode allowing reproducible indirect heating of the sensor. The sensor characteristics such as the apparent Michaelis constants K(M)(app) and maximum currents I(max)(app) were determined at different temperatures for the main substrate glucose as well as a potential interfering co-substrate maltose. The limit of detection increased with higher temperatures for both substrates (0.020 mM for glucose, and 0.023 mM for maltose at 48 degrees C). The substrate specificity of PQQ-sGDH is highly temperature dependent. Therefore, a mathematical model based on a multiple linear regression approach could be applied to discriminate between the current response for glucose and maltose. This allowed accurate determination of glucose in a concentration range of 0-0.1mM in the presence of unknown maltose concentrations ranging from 0 to 0.04 mM. 相似文献
444.
445.
Aleksander Jamsheer Anna Materna‐Kiryluk Magdalena Badura‐Stronka Katarzyna Wiśniewska Barbara Więckowska Jan Mejnartowicz Anna Balcar‐Boroń Maria Borszewska‐Kornacka Mieczysława Czerwionka‐Szaflarska Elżbieta Gajewska Urszula Godula‐Stuglik Marian Krawczynski Janusz Limon Józef Rusin Henryka Sawulicka‐Oleszczuk Ewa Szwałkiewicz‐Warowicka Janusz Świetliński Mieczysław Walczak Anna Latos‐Bieleńska 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(3):211-215
BACKGROUND: Amniotic rupture sequence (ARS) is a disruption sequence presenting with fibrous bands, possibly emerging as a result of amniotic tear in the first trimester of gestation. Our comparative study aims to assess whether there is a difference in the clinical pattern of congenital limb and internal organ anomalies between ARS with body wall defect (ARS‐BWD) and ARS without BWD (ARS‐L). METHODS: Among 1,706,639 births recorded between 1998 and 2006, 50 infants with a diagnosis of ARS were reported to the Polish Registry of Congenital Malformations. The information on 3 infants was incomplete, thus only 47 cases were analyzed. These infants were classified into groups of ARS‐L (38 infants) and ARS‐BWD (9 infants). RESULTS: The ARS‐BWD cases were more frequently affected by various congenital defects (overall p < 0.0001), and in particular by urogenital malformations (p = 0.003). In both groups, limb reduction defects occurred in approximately 80% of cases; however, minor and distal limb defects (phalangeal or digital amputation, pseudosyndactyly, constriction rings) predominated in the ARS‐L group (p = 0.0008). The ARS‐L group also had a higher frequency of hand and upper limb involvement. CONCLUSIONS: This observation suggests that amniotic band adhesion in ARS‐L takes place at a later development stage. Although limited by a small sample size, our study contributes to the growing evidence that both ARS entities represent two nosologically distinct conditions. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
446.
447.
Jerzy Macewicz Sławomir Orzechowski Urszula Dobrzy ska Sophie Haebel 《Acta Physiologiae Plantarum》2006,28(5):409-416
Barley biotypes from the world collection differ in their storage protein content even till 200 %. This is the first report
including results of the research, in which the structure of grains containing different amount of protein was tested to explain
this difference. The endosperm was investigated using scanning electron microscopy. The structure of the aleurone layer, storing
large quantities of protein, did not differ between the high- and low-protein forms of barley. It has been proven that the
large quantities of kernel protein may be stored in some cells of the zone adjacent to the aleurone layer, defined as the
subaleurone cells. It has been shown that morphologically uniform kernels of the same plant and even of the same ear can vary
greatly with respect to the number of these subaleurone cells. The purpose of the study was an examination of variation in
protein structure in single kernels of a fodder, a brewery and in an extra high-protein form of barley as well. Moreover the
studies were aimed to detect qualitative differences in the subaleurone protein. Application of mass spectrometry made possible
the identification of several kinds of proteins which were present in subaleurne layer of kernels. In the granule-bound protein
fraction isolated from the subaleurone type kernels, a much stronger representation of some protein was found, with the molecular
mass between 29 and 45 kDa, in comparison with the low-protein kernels. It is supposed, that these protein are isoforms of
z-type serpin and B3-hordein. 相似文献
448.
Birkner E Grucka-Mamczar E Zalejska-Fiolka J Chlubek D Kasperczyk S Stawiarska-Pieta B Blaszczyk U 《Biological trace element research》2006,112(2):169-174
The aim of the study was examining the effect of fluoride ions and caffeine administration on glucose and urea concentration
in blood serum and the activity of protein metabolism enzymes and selected enzymes of the urea cycle in rat liver. The study
was carried out using 18 male Sprague-Daowley rats (4.5 mo old). Rats were divided into three groups. Group I received distilled
water ad libitum. Group II received 4.9 mg F−/kg body mass/d of sodium fluoride in the water, and group III received sodium fluoride (in the above-mentioned dose) and
3 mg/kg body mass/d of caffeine in the water. After 50 d, the rats were anesthetized with thiopental and fluoride ions, glucose,
and urea concentration in blood serum were determined. Also determined were the activities of aspartate aminotransferase,
alanine aminotransferase glutamate dehydrogenase, ornithine carbamoylotransferase and arginase in liver homogenates. Liver
was taken for pathomorphological examinations. The applied doses of F− (4.9 mg/kg body mass/d) and F−+ caffeine (4.9 mg F−/kg body mass/d+3 mg caffeine/kg body mass/d) resulted in a statistically significant increase of fluoride ion concentration
in blood serum, a slight increase of the glucose concentration, and no changes in the concentration of urea in blood serum.
This might testify to the absence of kidney lesions for the applied concentrations of F−. No change in the functioning of hepatocytes was observed; however, slight disturbances have been noted in the functioning
of the liver, connected with the activation of urea cycle, increase of arginase activity, and accumulation of F− in this organ. There was no observed significant influence of caffeine supplementation on the obtained results. 相似文献
449.
Effect of Oleate on Neurotransmitter Transport and Other Plasma Membrane Functions in Rat Brain Synaptosomes 总被引:4,自引:3,他引:1
The effects of fatty acids, oleate and palmitate, on gamma-aminobutyric acid (GABA), aspartate, and 3,4- dihydroxyphenylethylamine (dopamine) transport and a variety of other membrane functions were studied in rat brain synaptosomes at a constant lipid-to-protein ratio. Under the conditions utilized oleate, but not palmitate, caused statistically significant changes in synaptosomal functions. Oleic acid inhibited the uptake of the amino acid neurotransmitters and dopamine in a tetrodotoxin-insensitive manner; it also induced the release of neurotransmitters from synaptosomes. The synaptosomal membrane potential decreased and the maximum GABA accumulation ratio [( GABA]i/[GABA]o) declined in parallel. The same depolarizing effect was seen in the presence of 50 microM verapamil or when chloride was replaced by propionate. The rate of respiration was stimulated by the unsaturated fatty acid; neither verapamil (50 microM) nor ouabain (100 microM) was effective in preventing the increase in oxygen consumption. By contrast, ruthenium red substantially decreased the stimulatory effect of oleate. The intrasynaptosomal [Ca2+] was increased by 40%, whereas [Na+]i remained unaltered. It is postulated that under the conditions used the inhibition of neurotransmitter uptake and the decrease in their accumulation caused by oleate result from the depolarization of synaptosomes that arises, at least in part, from increased permeability of the plasma membrane to calcium ions. 相似文献
450.
A case of Microsporum persicolor skin infection in a casual employee of a veterinary clinic in Montreal, Quebec, Canada, is reported. A survey of 80 wild rodents in the Montreal area resulted in the isolation of M. persicolor from two voles (Clethrionomys gapperi) and one deer mouse (Peromyscus maniculatus). One of the voles, heavily infested with parasites including ticks, had obvious lesions on the nose. This is the first report of M. persicolor in rodents in North America. 相似文献