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101.
Hepatic fibrosis and cirrhosis are worldwide health care problems, especially in regions with a high rate of hepatitis infection. As these diseases affect a major part of the human population, the search for antifibrotic therapies has a high priority in medical research. Transforming growth factor β1 (TGF-β1) is one of the most powerful profibrotic cytokines. Thus, blocking TGF-β1 activity by natural inhibitors represents a valid and logical strategy to combat hepatic fibrosis. One of the natural inhibitors of TGF-β1 is decorin, a small leucine-rich proteoglycan that binds with high affinity to this cytokine and prevents its interaction with pro-fibrotic receptors. Recent evidence has shown that decorin has a protective role in liver fibrogenesis insofar as its genetic ablation in mice leads to enhanced matrix deposition, impaired matrix degradation, and "activation" of hepatic stellate cells, the main producers of fibrotic tissue. Moreover, TGF-β1 exerts a stronger effect when functional decorin is absent. These data provide robust genetic evidence for a direct role of endogenous decorin in preventing and retarding hepatic fibrosis. Thus, boosting the endogenous production of decorin or systemic delivery of recombinant decorin could represent an additional therapeutic modality against hepatic fibrosis. 相似文献
102.
Farkas Z Márki-Zay J Kucsera J Vágvölgyi C Golubev WI Pfeiffer I 《Acta biologica Hungarica》2012,63(2):277-287
Wickerhamomyces anomalus VKM Y-159 strain produces two types of toxin designated as WAKT a and WAKT b, encoded by chromosomal genes. The WAKT a toxin is heat-labile, pronase sensitive acting in pH range 3-4 affecting on several yeasts including pathogenic Candida species while the WAKT b toxin is protease- and thermo-resistant, acting in pH range 3-7 on two species, Candida alai and Candida norvegica. The rapid decrease of the number of viable cells after toxin treatment demonstrates that both toxins have cytocidic effect. 相似文献
103.
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
104.
Attila Sipos Zsolt Török Erzsébet Rőth Attila Kiss-Szikszai Gyula Batta Ilona Bereczki Zsolt Fejes Anikó Borbás Eszter Ostorházi Ferenc Rozgonyi Lieve Naesens Pál Herczegh 《Bioorganic & medicinal chemistry letters》2012,22(23):7092-7096
The primary amino function of teicoplanin pseudoaglycon has been transformed into arylthioisoindole or benzoisoindole and glycosylthioisoindole derivatives, in a reaction with o-phthalaldehyde or naphtalene-2,3-dicarbaldehyde and various thiols. All of the obtained semisynthetic antibiotics exhibited potent antibacterial activities against Gram-positive bacteria in the ng per ml concentration range. A few of them showed antiviral activity, in particular against influenza virus. 相似文献
105.
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
106.
107.
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
108.
109.
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
110.
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