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91.
The effect of two different iron chelates and iron concentration on multiplication, shoot growth, chlorophyll content and rooting of Carlina onopordifolia were studied in in vitro culture. FeEDTA presented in MS basal medium was replaced by FeEDDHA, which was applied in three concentrations: 93.5, 187.0 and 280.5?mg?dm?3 (5.6?mg?dm?3, 11.2 and 16.8?mg?dm?3 Fe ions, respectively). Changing chelate or iron concentration in the medium had no effect on axillary shoot number proliferation, but growth of shoots was significantly inhibited by a two- and three-fold increase in concentration of FeEDDHA in the medium. Supplementation of the medium with FeEDDHA as Fe source significantly increased the level of chlorophyll in the leaves. After treatment of shoots with IBA for 5?s and growing them on the MS medium supplemented with FeEDTA, the number of roots per shoot was significantly higher than on medium containing FeEDDHA. Increasing the concentration of Fe ions in the medium after a short pulse (5?s) of IBA had no effect on shoot rooting. After 30?s of 1-g?dm?3 IBA treatment, growth of roots on medium with FeEDDHA was stimulated. The survival rate was relatively low and did not depend on the type and concentration of iron chelate in the rooting medium. 相似文献
92.
Hromadnikova I 《DNA and cell biology》2012,31(7):1221-1232
Since the placenta is being continuously remodeled during normal placental development, extracellular nucleic acids of both fetal and placental origin, packed into either trophoblast-derived apoptotic bodies or shedding syncytiotrophoblast microparticles, may be detected in maternal circulation during the course of normal gestation. Placental-insufficiency-related pregnancy complications have been shown to be associated with excessive placental trophoblast apoptosis and shedding of placenta debris. Recent advances in the field are reviewed with a focus on the diagnostic potential of particular molecular biomarkers and their eventual implementation in the currently used predictive and diagnostic algorithms for placental-insufficiency-related pregnancy complications. 相似文献
93.
Pomajbíková K Petrželková KJ Petrášová J Profousová I Kalousová B Jirků M Sá RM Modrý D 《The Journal of eukaryotic microbiology》2012,59(1):97-99
Trophozoites of Troglocorys cava were detected in all but one of the wild chimpanzee populations from Rubondo Island (Tanzania), with a prevalence ranging between 20% and 78%. However, the ciliate was absent in all captive groups. Prevalence appeared to increase with the number of sequential samples taken from a particular individual and reached 95.5% in wild individuals sampled at least 4 times. 相似文献
94.
95.
Ilona Lipp Mathias Benedek Andreas Fink Karl Koschutnig Gernot Reishofer Sabine Bergner Anja Ischebeck Franz Ebner Aljoscha Neubauer 《PloS one》2012,7(12)
The neural efficiency hypothesis postulates an inverse relationship between intelligence and brain activation. Previous research suggests that gender and task modality represent two important moderators of the neural efficiency phenomenon. Since most of the existing studies on neural efficiency have used ERD in the EEG as a measure of brain activation, the central aim of this study was a more detailed analysis of this phenomenon by means of functional MRI. A sample of 20 males and 20 females, who had been screened for their visuo-spatial intelligence, was confronted with a mental rotation task employing an event-related approach. Results suggest that less intelligent individuals show a stronger deactivation of parts of the default mode network, as compared to more intelligent people. Furthermore, we found evidence of an interaction between task difficulty, intelligence and gender, indicating that more intelligent females show an increase in brain activation with an increase in task difficulty. These findings may contribute to a better understanding of the neural efficiency hypothesis, and possibly also of gender differences in the visuo-spatial domain. 相似文献
96.
Clara cells are non-ciliated, secretory bronchiolar epithelial cells that serve to detoxify harmful inhaled substances. Clara cells also function as stem/progenitor cells for repair in the bronchioles. Clara cell secretory protein (CCSP) is specifically expressed in pulmonary Clara cells and is widely used as a Clara cell marker. In addition CCSP promoter is commonly used to direct gene expression into the lung in transgenic models. The discovery of CCSP immunoreactivity in plasma membranes of airway lining cells prompted us to explore the possibility of enriching Clara cells by flow cytometry. We established a novel and simple method for the isolation of CCSP-expressing cell Clara cells using a combination of mechanical and enzymatic dissociation followed by flow cytometry sorting technology. We showed that ~25% of dissociated cells from whole lung expressed CCSP. In the resulting preparation, up to 98% of cells expressed CCSP. Notably, we found that several common stem cell markers including CD44, CD133, Sca-1 and Sox2 were expressed in CCSP(+) cells. Moreover, CCSP(+) cells were able to form spheroid colonies in vitro with 0.97‰ efficiency. Parallel studies in vivo confirmed that a small population of CCSP(-)expressing cells in mouse airways also demonstrates stem cell-like properties such as label retention and harboring rare bronchioalveolar stem cells (BASCs) in terminal bronchioles (TBs). We conclude that CCSP(+) cells exhibit a number of stem cell-like features including stem cell marker expression, bronchosphere colony formation and self-renewal ability. Clara cell isolation by flow cytometry sorting is a useful method for investigating the function of primary Clara cells in stem cell research and mouse models. 相似文献
97.
Brandes V Schelle I Brinkmann S Schulz F Schwarz J Gerhard R Genth H 《Biological chemistry》2012,393(1-2):77-84
Toxin A (TcdA) and toxin B (TcdB) are the major virulence factors of Clostridium difficile-associated diarrhoea (CDAD). TcdA and TcdB mono-glucosylate small GTPases of the Rho family, thereby causing actin re-organisation in colonocytes, resulting in the loss of colonic barrier function. The hydrophilic bile acid tauroursodeoxycholic acid (TUDCA) is an approved drug for the treatment of cholestasis and biliary cirrhosis. In this study, TUDCA-induced activation of Akt1 is presented to increase cellular levels of pS71-Rac1/Cdc42 in human hepatocarcinoma (HepG2) cells, showing for the first time that bile acid signalling affects the activity of Rho proteins. Rac1/Cdc42 phosphorylation, in turn, protects Rac1/Cdc42 from TcdB-catalysed glucosylation and reduces the TcdB-induced cytopathic effects in HepG2 cells. The results of this study indicate that TUDCA may prove useful as a therapeutic agent for the treatment of CDAD. 相似文献
98.
Gaál EI Salo P Kristiansson K Rehnström K Kettunen J Sarin AP Niemelä M Jula A Raitakari OT Lehtimäki T Eriksson JG Widen E Günel M Kurki M von und Zu Fraunberg M Jääskeläinen JE Hernesniemi J Järvelin MR Pouta A;International Consortium for Blood Pressure Genome-Wide Association Studies Newton-Cheh C Salomaa V Palotie A Perola M 《PLoS genetics》2012,8(3):e1002563
Although genome-wide association studies (GWAS) have identified hundreds of complex trait loci, the pathomechanisms of most remain elusive. Studying the genetics of risk factors predisposing to disease is an attractive approach to identify targets for functional studies. Intracranial aneurysms (IA) are rupture-prone pouches at cerebral artery branching sites. IA is a complex disease for which GWAS have identified five loci with strong association and a further 14 loci with suggestive association. To decipher potential underlying disease mechanisms, we tested whether there are IA loci that convey their effect through elevating blood pressure (BP), a strong risk factor of IA. We performed a meta-analysis of four population-based Finnish cohorts (n(FIN) = 11 266) not selected for IA, to assess the association of previously identified IA candidate loci (n = 19) with BP. We defined systolic BP (SBP), diastolic BP, mean arterial pressure, and pulse pressure as quantitative outcome variables. The most significant result was further tested for association in the ICBP-GWAS cohort of 200 000 individuals. We found that the suggestive IA locus at 5q23.2 in PRDM6 was significantly associated with SBP in individuals of European descent (p(FIN) = 3.01E-05, p(ICBP-GWAS) = 0.0007, p(ALL) = 8.13E-07). The risk allele of IA was associated with higher SBP. PRDM6 encodes a protein predominantly expressed in vascular smooth muscle cells. Our study connects a complex disease (IA) locus with a common risk factor for the disease (SBP). We hypothesize that common variants in PRDM6 can contribute to altered vascular wall structure, hence increasing SBP and predisposing to IA. True positive associations often fail to reach genome-wide significance in GWAS. Our findings show that analysis of traditional risk factors as intermediate phenotypes is an effective tool for deciphering hidden heritability. Further, we demonstrate that common disease loci identified in a population isolate may bear wider significance. 相似文献
99.
Kopera I Tuz R Kotula-Balak M Schwarz T Koczanowski J Bilinska B 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2008,309(3):117-126
In this study we thoroughly scrutinized testes morphology and investigated whether treatment of recipient boars with gonadotropin-releasing hormone (GnRH)-agonist deslorelin could alter the expression of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), luteinizing hormone receptors (LHRs), and androgen receptors (ARs) in testicular cells. An implant containing 4.7 mg of the GnRH-agonist deslorelin was subcutaneously inserted into crossbred male pigs at 91 and 147 days of age. Testicular traits, morphology of the testes, the proteins' expression, and testosterone concentration in blood plasma were analyzed in all boars after slaughter at 175 days of age. Histological analysis revealed significant alterations in both the interstitial tissue and seminiferous tubules of experimental animals after 28 and 84 days of deslorelin treatment. The intensity of the AR immunostaining within the testis appeared as a function of the severity of testicular dysgenesis. Time-dependent action of deslorelin on the expression of LHR and 3beta-HSD in Leydig cells was also detected. Staining for LHR and 3beta-HSD was very weak or the Leydig cells were immunonegative. Concomitantly, a significant decrease in plasma testosterone level was found in both groups of deslorelin-treated boars when compared with the control group. This is the first report showing the cellular distribution of AR, LHR, and 3beta-HSD in testicular cells of deslorelin-treated boars. It is concluded that morphological and immunohistochemical studies are important for the evaluation of testicular histoarchitecture and steroidogenic function. Subsequently, the endocrine control of reproduction in the GnRH-agonist deslorelin-treated males will be better understood. 相似文献
100.