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121.
Ferens-Sieczkowska M Midro A Mierzejewska-Iwanowska B Zwierz K Katnik-Prastowska I 《Glycoconjugate journal》1999,16(10):573-577
Alterations in haptoglobin (Hp) glycosylation were examined in the plasma of the first patient with carbohydrate-deficient glycoprotein syndrome (CDGS) who was described in Poland. Hp concentration in the CDGS patient plasma was low (240mg/l) and the Hp phenotype was shown to be 2-2. Three glycoforms of the Hp subunit were observed in SDS-PAGE in CDGS. The densitometric analysis and molecular weight determinations suggested that 50% of glycoforms were fully glycosylated; 30% contained three out of four and 20% only two out of four glycan units compared to those that are present in Hp derived from healthy people. Results with lectins (concanavalin A and Sambucus nigra, Maackia amurensis and Alleuria aurantia agglutinins) indicate that all three glycoforms of subunit of CDGS-Hp contained biantennary complex glycans terminated with 2,6 bound sialic acid, but without fucose or 2,3 linked sialic acid. Hp glycosylation abnormalities described in this work suggest that this case was a type I carbohydrate-deficient glycoprotein syndrome. 相似文献
122.
123.
Effects of anesthetics on systemic hemodynamics in mice 总被引:1,自引:0,他引:1
Janssen BJ De Celle T Debets JJ Brouns AE Callahan MF Smith TL 《American journal of physiology. Heart and circulatory physiology》2004,287(4):H1618-H1624
The aim of this study was to compare the systemic hemodynamic effects of four commonly used anesthetic regimens in mice that were chronically instrumented for direct and continuous measurements of cardiac output (CO). Mice (CD-1, Swiss, and C57BL6 strains) were instrumented with a transit-time flow probe placed around the ascending aorta for CO measurement. An arterial catheter was inserted into the aorta 4 or 5 days later for blood pressure measurements. After full recovery, hemodynamic parameters including stroke volume, heart rate, CO, mean arterial pressure (MAP), and total peripheral resistance were measured with animals in the conscious state. General anesthesia was then induced in these mice using isoflurane (Iso), urethane, pentobarbital sodium, or ketamine-xylazine (K-X). The doses and routes of administration of these agents were given as required for general surgical procedures in these animals. Compared with the values obtained for animals in the conscious resting state, MAP and CO decreased during all anesthetic interventions, and hemodynamic effects were smallest for Iso (MAP, -24 +/- 3%; CO, -5 +/- 7%; n = 15 mice) and greatest for K-X (MAP, -51 +/- 6%; CO, -37 +/- 9%; n = 8 mice), respectively. The hemodynamic effects of K-X were fully antagonized by administration of the alpha(2)-receptor antagonist atipamezole (n = 8 mice). These results indicate that the anesthetic Iso has fewer systemic hemodynamic effects in mice than the nonvolatile anesthetics. 相似文献
124.
Mouse development and cell proliferation in the absence of D-cyclins 总被引:41,自引:0,他引:41
Kozar K Ciemerych MA Rebel VI Shigematsu H Zagozdzon A Sicinska E Geng Y Yu Q Bhattacharya S Bronson RT Akashi K Sicinski P 《Cell》2004,118(4):477-491
D-type cyclins (cyclins D1, D2, and D3) are regarded as essential links between cell environment and the core cell cycle machinery. We tested the requirement for D-cyclins in mouse development and in proliferation by generating mice lacking all D-cyclins. We found that these cyclin D1(-/-)D2(-/-)D3(-/-) mice develop until mid/late gestation and die due to heart abnormalities combined with a severe anemia. Our analyses revealed that the D-cyclins are critically required for the expansion of hematopoietic stem cells. In contrast, cyclin D-deficient fibroblasts proliferate nearly normally but show increased requirement for mitogenic stimulation in cell cycle re-entry. We found that the proliferation of cyclin D1(-/-)D2(-/-)D3(-/-) cells is resistant to the inhibition by p16(INK4a), but it critically depends on CDK2. Lastly, we found that cells lacking D-cyclins display reduced susceptibility to the oncogenic transformation. Our results reveal the presence of alternative mechanisms that allow cell cycle progression in a cyclin D-independent fashion. 相似文献
125.
A number of in planta transformation protocols that avoid long culture under sterile conditions were developed for Arabidopsis thaliana. The most widely used methods are based on vacuum infiltration and floral dip. These methods were adapted for transformation
of other species as well. Successful in planta transformations of alfalfa, radish, pakchoi and petunia were reported recently. In this short review we present several modified
procedures originally developed for Arabidopsis thaliana and in some cases adapted to other species. We emphasize the crucial parameters involved in in planta transformation. We also describe here the studies attempting to shed light on the mechanisms and estimating the cellular
target of transformation, which may help in transforming new plant species. 相似文献
126.
Kwiecień RA Rostkowski M Dybała-Defratyka A Paneth P 《Journal of inorganic biochemistry》2004,98(6):1078-1086
Several semiempirical methods (MNDO-d, PM3tm, PM3-d, PM5, PM6, and AM1-d) have been tested against experimental data and density functional theory (DFT) results in search for the best methods that can be used for quantum-mechanical-molecular mechanics (QM/MM) modeling of corrinoid systems of vitamin B(12) co-factor. It has been found that the PM6 parametrization in its present form gives results closest to hybrid DFT calculations that are most widely used thus far. In comparison with pure DFT and experimental data the best agreement is obtained for PM3tm parametrization, while PM6 yields slightly worse results. AM1-d yields bad geometry of the corrin moiety. The worst performance was observed for MNDO-d, which has severe problem with position and orientation of the alpha-ligands. 相似文献
127.
Gralak MA Bertrandt J Klos A Stryczek AB Piastowska AW Morka A Debski B 《Biological trace element research》2004,98(1):85-93
The aim of the present study was to investigate the influence of nutritional deficiency and dietary addition of vitamins (B2, B6, and folate) on hepatic concentration of zinc and copper in rats. The experiment was performed on 260 growing male Wistar
rats divided into 13 groups. Animals of 11 groups were fed isocaloric diets (14.7 MJ/kg) in which the 20% of energy was derived
from protein. Another two groups of rats were offered diets with 9% or 4.5% of energy originating from protein. Animals of
both mentioned groups and of the control group (20% of energy from protein) were offered diets ad libitum. The other 10 groups were offered 50% and 30% of the amount consumed in the control group. Eight groups, from those 10 restricted
ones, were differentiated by dietary addition of vitamins B2 and B6 and folate (300% addition). Restricted feed intake did not affect the liver zinc concentration but significantly increased
the copper concentration. The addition of vitamin B6 decreased the liver Zn concentration. The highest liver Cu concentration was noted in rats offered restricted diets to only
30% of intake in the control group and high in vitamin B2 and in rats supplemented with all of studied vitamins together. It suggests that vitamin B2 had the strongest impact on liver Cu concentration in rats fed restricted diets. 相似文献
128.
Essential role of Mia40 in import and assembly of mitochondrial intermembrane space proteins 总被引:11,自引:0,他引:11
Chacinska A Pfannschmidt S Wiedemann N Kozjak V Sanjuán Szklarz LK Schulze-Specking A Truscott KN Guiard B Meisinger C Pfanner N 《The EMBO journal》2004,23(19):3735-3746
Mitochondria import nuclear-encoded precursor proteins to four different subcompartments. Specific import machineries have been identified that direct the precursor proteins to the mitochondrial outer membrane, inner membrane or matrix, respectively. However, a machinery dedicated to the import of mitochondrial intermembrane space (IMS) proteins has not been found so far. We have identified the essential IMS protein Mia40 (encoded by the Saccharomyces cerevisiae open reading frame YKL195w). Mitochondria with a mutant form of Mia40 are selectively inhibited in the import of several small IMS proteins, including the essential proteins Tim9 and Tim10. The import of proteins to the other mitochondrial subcompartments does not depend on functional Mia40. The binding of small Tim proteins to Mia40 is crucial for their transport across the outer membrane and represents an initial step in their assembly into IMS complexes. We conclude that Mia40 is a central component of the protein import and assembly machinery of the mitochondrial IMS. 相似文献
129.
130.
Papasavvas E Kostman JR Mounzer K Grant RM Gross R Gallo C Azzoni L Foulkes A Thiel B Pistilli M Mackiewicz A Shull J Montaner LJ 《PLoS medicine》2004,1(3):e64