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981.
Two-dimensional electrophoresis (2-DE) of soluble proteins and enzymes was performed and specific activities of 5 enzymes (esterase, pectinesterase, acid phosphatase, protease and diaphorase) were determined in stigmas of Lolium multiflorum (Italian ryegrass) treated with self or foreign pollen coat eluates (pc). Also, a low-molecular-weight fraction of the treated self-compatible (SC) and self-incompatible (SI) stigmas was analyzed by high-pressure liquid chromatography (HPLC). The treatment of stigmas with foreign pollen induced the loss of 42% of the control sample proteins in SC plants but only of 5.5% in SI plants. In contrast, the treatment of stigmas with foreign pollen induced the loss of 15% proteins in SC plants and of 29% in SI plants. Specific activities of esterase, pectinesterase and diaphorase were higher in SC than in SI stigmas. The 2-DE enzyme patterns indicated qualitative relationships between the presence of some isoforms of acid phosphatase or protease and the treatment with self or foreign pc in SC and SI stigmas. No changes were observed in HPLC profiles of the low-molecular-weight fraction from SC and SI stigmas treated or not with pc. The presented results revealed different reactions of SC and SI stigmas to the treatment with self or foreign pc. Further investigations may explain if any of the observed reactions represent specific reorientations in the style, facilitating cross- or self-pollination. 相似文献
982.
Constantinou M Binka-Kowalska A Borkowska E Zajac E Jałmuzna P Matych J Nawrocka A Kałuzewski B 《Journal of applied genetics》2006,47(3):273-275
Multiplex FISH (UroVysion), Comparative Genomic Hybridization (CGH), and Multitemperature Single-Strand Conformation Polymorphism (MSSCP) were applied for non-invasive diagnosis and prognosis of bladder cancer. The UroVysion test was positive in 80% of patients with pT1 and in 100% of patients with either pT2 or pT3 tumours. Tumours with pT3T4 stages were characterized by high numbers of chromosomal imbalances, detected by CGH. The mutation of the p53 gene was detected in 16% of patients, but only in those with pT2 or pT3 tumours. 相似文献
983.
Zieminska E Stafiej A Pitsinos EN Couladouros EA Moutsos V Kozlowska H Toczylowska B Lazarewicz JW 《Neuro-Signals》2006,15(6):283-292
Although the interactions of several natural bastadins with the RyR1 isoform of the ryanodine receptor in sarcoplasmic reticulum has been described, their structure-dependent interference with the RyR2 isoform, mainly expressed in cardiac muscle and brain neurons, has not been studied. In this work, we examined calcium transients induced by natural bastadin 10 and several synthetic bastadins in cultured cerebellar granule cells known to contain RyR2. The fluorescent calcium indicator fluo-3 and confocal microscopy were used to evaluate changes in the intracellular Ca(2+) concentration (Ca(i)), and the involvement of ryanodine receptors was assessed using pharmacological tools. Our results demonstrate that apart from the inactive BAST218F6 (a bisdebromo analogue of bastadin 10), synthetic bastadin 5, and synthetic analogues BAST217B, BAST240 and BAST268 (at concentrations >20 microM) increased Ca(i) in a concentration-dependent, ryanodine- and FK-506-sensitive way, with a potency significantly exceeding that of 20 mM caffeine. Moreover, the same active bastadins at a concentration of 5 muM in the presence of ryanodine prevented a thapsigargin-induced increase in Ca(i). These results indicate that bastadins, acting in a structure-dependent manner, modify the activity of RyR2 in primary neuronal culture and provide new information about structure-related pharmacological properties of bastadins. 相似文献
984.
Rychter P Biczak R Herman B Smyłła A Kurcok P Adamus G Kowalczuk M 《Biomacromolecules》2006,7(11):3125-3131
The degradation of poly[(R,S)-3-hydroxybutyrate], a-PHB, binary blends with natural PHB (n-PHB) and poly(L-lactic acid), PLLA, respectively, has been investigated in soil. In such a natural environment, a-PHB blend component was found to biodegrade. The degradation of a-PHB-containing blends proceeded faster than that of respective plain n-PHB and PLLA. The molecular weight decrease of the n-PHB component was higher, while the same rate of bioerosion of both components was observed for the a-PHB/n-PHB binary blend. For the a-PHB blend with PLLA, the weight loss was accompanied by blend composition changes and the decrease of a-PHB content. However, the PLLA molecular weight decrease was lower in the blend in comparison with the plain PLLA sample. The increase of the number of microorganisms particularly observed for the soil where binary blends were incubated indicates that microbial degradation of a-PHB takes place. The terrestrial plant growth test (cress and barley) demonstrates no environmental toxicity of the materials studied. 相似文献
985.
Małgorzata D. Gaj Aneta Trojanowska Agnieszka Ujczak Martyna Mędrek Aleksandra Kozioł Beata Garbaciak 《Plant Growth Regulation》2006,49(2-3):183-197
Plant hormones are considered to be the key factors involved in triggering in vitro induced plant morphogenesis, including somatic embryogenesis (SE). Mutants affected in SE and altered in hormonal response therefore provide valuable material for genetic research on in vitro induced plant embryogenesis. The capacity for SE was studied in 27 mutants with defects in response to different plant hormones: auxin, ABA, gibberellin and cytokinin, and evaluated in 2-week-old mutant and wild-type cultures in terms of their efficiency and productivity. SE was induced in vitro via a direct morphogenic pathway, through the culture of immature zygotic embryos on standard solid medium with 5 μM 2,4-D. The majority of the analyzed mutants displayed a significantly impaired capacity for SE; and those affected belonged to several different hormone-defective groups, including forms affected in auxin (axr4), gibberellin (ga) and ABA (abi, hyl1, cpb20, abh1) response. These mutants showed a significant decrease in embryogenic response as manifested by a low efficiency and/or productivity of SE. Additionally, SE efficiency was analyzed for axr4-1 mutant on media supplemented with different auxins while GA3 and inhibitors of gibberellins (uniconazol P and paclobutrazol), were applied for pkl1-1-mutant. The selected mutants provide a valuable research tool for studying the molecular mechanisms determining the induction of embryogenesis in cultures of somatic tissues. Their usefulness in further studies is discussed. 相似文献
986.
The CART receptors: background and recent advances 总被引:1,自引:0,他引:1
Previous evidence obtained from several behavioral and biochemical studies suggested the existence of multiple CART receptors. However, identification of CART receptor binding has been largely unsuccessful until recently. The first evidence of CART signaling properties came from a study demonstrating that CART 55-102 inhibited voltage-dependent intracellular calcium signaling. More recent studies showed CART-induced dose- and time-dependent activation of extracellular signal-regulated kinase (ERK) 1 and 2 in AtT20 cell line. The activation of ERK was blocked by pertussis toxin but not genisten suggesting the involvement of Gi/o linked cascade in CART's signaling properties in AtT20 cells. Shortly after these findings, the evidence of CART 61-102 specific binding was obtained from the same cell line. This study demonstrated that [(125)I]-CART 61-102 was displaced only by active CART peptide but not by inactive CART fragments or several other unrelated peptides or drugs. The [(125)I]-CART 61-102 binding was saturable and it had a high affinity for a single site in AtT20 cells. The binding was also dependent on time, pH, temperature and protein concentration. The average (+/-S.E.M.) B(max) and K(d) values were 101.4+/-8.8 fmol/mg protein and 21.9+/-8.0 pM, respectively. These data indicate the existence of specific CART receptor binding in AtT20 cells where CART signaling has been demonstrated. The identification of a receptor clone in these cells may help us elucidate CART receptors in other tissues. Because CART is implicated with several physiological functions including feeding, drug reward and stress, identification of a CART receptor would provide a novel target for the development of pharmacological tools and drugs for obesity and other disorders. 相似文献
987.
Birkner E Kasperczyk S Zalejska-Fiolka J Kasperczyk A Birkner B 《Biological trace element research》2006,111(1-3):137-149
The aim of this study was to investigate the effect of combined therapy of vitamin E and selenomethionine to pro/ antioxidant
status in experimental hypercholesterolemia. Thirty male rabbits were included in the study and randomized into five groups
consisting of the control group (standard diet) and four experimental groups staying on a diet rich in cholesterol (0.5 g/100
g diet): cholesterol group and groups supplemented cholesterol with selenomethionine (12.5 μg/kg body mass/24 h) or vitamin
E (10 mg of Dl-α-tocopherol/kg body mass/24 h) or combination of the above antioxidants for 3 mo. The activity of superoxide dismutase (SOD),
glutathione peroxidase (GPX), and catalase (CAT) as well as the concentration of malondialdehyde (MDA) was estimated in the
blood during every month of experiment. Increased activity of SOD and GPX with a decreased concentration of MDA in comparison
to the cholesterol diet was found mainly in the combination of study antioxidants. The supplementation of the cholesterol
diet with combined doses of vitamin E and selenomethionine appears to prevent the lesions induced by experimental hypercholesterolemia
much more efficiently than single doses of the above. 相似文献
988.
Narbutt J Lesiak A Sysa-Jedrzejowska A Smolewski P Robak T Zalewska A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2006,44(1):61-63
Human blood dendritic cells (BDC) can be divided into three subsets: plasmacytoid DC (PDC) and two myeloid subsets--MDC1 and MDC2. Several studies revealed the presence of both MDC and PDC in blood of healthy subjects, however no precise literature data exist on the number and distribution of BDC in the skin. The aim of our study was to assess the number and distribution of BDC and their subtypes in the healthy skin. The-study included 30 healthy volunteers (age 18-51). Punch biopsies were taken from the buttock skin from each subject, and immunofluorescent staining was performed using monoclonal mouse IgG1 antibodies directed against BDCA-1, BDCA-2, BDCA-3 and BDC-4. The BDC were present both in the epidermis and dermis. PDC were detected mainly in the dermis (mean 1.2 cells per field). Myeloid subtypes were observed mainly in the middle layers of the epidermis and in the upper part of the dermis (mean 1.8 cells per field). The detection of blood dendritic cells in the skin proves their role in immune cutaneous surveillance. 相似文献
989.
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
990.
Plasma copper concentrations in pathological pregnancies. 总被引:1,自引:0,他引:1
Ana Alebic-Juretic Aleksandra Frkovic 《Journal of trace elements in medicine and biology》2005,19(2-3):191-194
Copper is an essential element required for the formation of many enzymes with important roles in the human body. During pregnancy, the maternal serum copper concentration is increased due to the higher levels of ceruloplasmin that are the result of elevated oestrogen levels. The aim of this work was to investigate maternal plasma copper concentrations in relation to various pathological conditions during pregnancy. A total of 319 maternal plasma samples were analysed: 103 taken from women in the first trimester, 73 in the second trimester, 99 in the third trimester of pregnancy and 44 at delivery. The plasma concentration of copper during each trimester of normal pregnancy was taken as a reference value. Group comparisons performed by analysis of variance (ANOVA) followed by Dunnett test indicated substantially lower plasma concentrations of copper in pathological conditions diagnosed during the first trimester of pregnancy (spontaneous abortion, threatened abortion, missed abortion and blighted ovum). No significant differences in maternal plasma blood copper concentrations were found in pathological conditions (threatened abortion, threatened preterm delivery and pyelonephritis) diagnosed in the second trimester of pregnancy. Significant differences in plasma copper concentrations were found in the third trimester, for which finding the Dunnett test indicated the cholestasis group to be responsible. Except for twin pregnancy, a tendency to higher plasma copper concentrations, however not statistically significant, was observed in other pathological conditions during the third trimester (gestosis, intrauterine growth retardation, preterm labour). 相似文献