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71.
Victor van der Meer Henk F van Stel Moira J Bakker Albert C Roldaan Willem JJ Assendelft Peter J Sterk Klaus F Rabe Jacob K Sont 《Respiratory research》2010,11(1):74
Background
Internet-based self-management has shown to improve asthma control and asthma related quality of life, but the improvements were only marginally clinically relevant for the group as a whole. We hypothesized that self-management guided by weekly monitoring of asthma control tailors pharmacological therapy to individual needs and improves asthma control for patients with partly controlled or uncontrolled asthma.Methods
In a 1-year randomised controlled trial involving 200 adults (18-50 years) with mild to moderate persistent asthma we evaluated the adherence with weekly monitoring and effect on asthma control and pharmacological treatment of a self-management algorithm based on the Asthma Control Questionnaire (ACQ). Participants were assigned either to the Internet group (n = 101) that monitored asthma control weekly with the ACQ on the Internet and adjusted treatment using a self-management algorithm supervised by an asthma nurse specialist or to the usual care group (UC) (n = 99). We analysed 3 subgroups: patients with well controlled (ACQ ≤ 0.75), partly controlled (0.75>ACQ ≤ 1.5) or uncontrolled (ACQ>1.5) asthma at baseline.Results
Overall monitoring adherence was 67% (95% CI, 60% to 74%). Improvements in ACQ score after 12 months were -0.14 (p = 0.23), -0.52 (p < 0.001) and -0.82 (p < 0.001) in the Internet group compared to usual care for patients with well, partly and uncontrolled asthma at baseline, respectively. Daily inhaled corticosteroid dose significantly increased in the Internet group compared to usual care in the first 3 months in patients with uncontrolled asthma (+278 μg, p = 0.001), but not in patients with well or partly controlled asthma. After one year there were no differences in daily inhaled corticosteroid use or long-acting β2-agonists between the Internet group and usual care.Conclusions
Weekly self-monitoring and subsequent treatment adjustment leads to improved asthma control in patients with partly and uncontrolled asthma at baseline and tailors asthma medication to individual patients'' needs.Trial registration
Current Controlled Trials ISRCTN79864465 相似文献72.
Background
The assembly and spatial organization of enzymes in naturally occurring multi-protein complexes is of paramount importance for the efficient degradation of complex polymers and biosynthesis of valuable products. The degradation of cellulose into fermentable sugars by Clostridium thermocellum is achieved by means of a multi-protein "cellulosome" complex. Assembled via dockerin-cohesin interactions, the cellulosome is associated with the cell surface during cellulose hydrolysis, forming ternary cellulose-enzyme-microbe complexes for enhanced activity and synergy. The assembly of recombinant cell surface displayed cellulosome-inspired complexes in surrogate microbes is highly desirable. The model organism Lactococcus lactis is of particular interest as it has been metabolically engineered to produce a variety of commodity chemicals including lactic acid and bioactive compounds, and can efficiently secrete an array of recombinant proteins and enzymes of varying sizes. 相似文献73.
74.
Santamaría E Muñoz J Fernandez-Irigoyen J Sesma L Mora MI Berasain C Lu SC Mato JM Prieto J Avila MA Corrales FJ 《Journal of proteome research》2006,5(4):944-953
S-adenosylmethionine arises as a central molecule in the preservation of liver homeostasis as a chronic hepatic deficiency results in spontaneous development of steatohepatitis and hepatocellular carcinoma. In the present work, we have attempted a comprehensive analysis of proteins associated with hepatocarcinogenesis in MAT1A knock out mice using a combination of two-dimensional electrophoresis and mass spectrometry, to then apply the resulting information to identify hallmarks of human HCC. Our results suggest the existence of individual-specific factors that might condition the development of preneoplastic lesions. Proteomic analysis allowed the identification of 151 differential proteins in MAT1A-/- mice tumors. Among all differential proteins, 27 changed in at least 50% of the analyzed tumors, and some of these alterations were already detected months before the development of HCC in the KO liver. The expression level of genes coding for 13 of these proteins was markedly decreased in human HCC. Interestingly, seven of these genes were also found to be down-regulated in a pretumoral condition such as cirrhosis, while depletion of only one marker was assessed in less severe liver disorders. 相似文献
75.
Pascual G Rodríguez M Corrales C Turégano F García-Honduvilla N Bellón JM Buján J 《Cryobiology》2004,48(1):62-71
The endothelial loss provoked by the methods of vascular cryopreservation used at most human vessel banks is one of the main factors leading to the failure of grafting procedures performed using cryopreserved vessel substitutes. This study evaluates the effects of the storage temperature and thawing protocol on the endothelial cell loss suffered by cryopreserved vessels, and optimises the thawing temperature and protocol for cryopreserving arterial grafts in terms of that producing least endothelial loss. Segments of the common iliac artery of the minipig (n = 20) were frozen at a temperature reduction rate of 1 degrees C/min in a biological freezer. After storing the arterial fragments for 30 days, study groups were established according to the storage temperature (-80, -145 or -196 degrees C) and subsequent thawing procedure (slow or rapid thawing). Fresh vessel segments served as the control group. Once thawed, the specimens were examined by light, transmission, and scanning electron microscopy. The covered endothelial surface was determined by image analysis. Data for the different groups were compared by one way ANOVA. When cryopreservation at each of the storage temperatures was followed by slow thawing, the endothelial cells showed improved morphological features and viability over those of specimens subjected to rapid thawing. Rapidly thawed endothelial cells showed irreversible ultrastructural damage such as mitochondrial dilation and rupture, reticular fragmentation, and peripheral nuclear condensation. In contrast, slow thawing gave rise to changes compatible with reversible damage in a large proportion of the endothelial cells: general swelling, reticular dilation, mitochondrial swelling, and nuclear chromatin condensation. Gradually thawed cryopreserved arteries showed a lower proportion of damaged cells identified by the TUNEL method compared to the corresponding rapidly thawed specimens (p < 0.05, for all temperatures). In all the groups in which vessels underwent rapid thawing (except at -145 degrees C), significant differences (p < 0.05) in endothelial cover values were recorded with respect to control groups. Storage of cryopreserved vessels at -80 degrees C followed by rapid thawing led to greatest endothelial cell loss (61.36+/-9.06% covered endothelial surface), while a temperature of -145 degrees C followed by slow thawing was best at preserving the endothelium of the vessel wall (89.38+/-16.67% surface cover). In conclusion, storage at a temperature of -145 degrees C in nitrogen vapour followed by gradual automated thawing seems to be the best way of preserving the endothelial surface of the arterial cryograft. This method gives rise to best endothelial cell viability and cover values, with obvious benefits for subsequent grafting. 相似文献
76.
Previously, treatment of Tamm-Horsfall glycoprotein (THp) from different
donors with endo-beta-galactosidase has been shown to liberate a tetra- and
a Sd(a)-active pentasaccharide, concluding the presence of N-linked
carbohydrate chains containing additional N - acetyllactosamine units.
These type of oligosaccharides were not found in a detailed structure
elucidation of the carbohydrate moiety of THp of one male donor, suggesting
a donor-specific feature for these type of structures. Therefore, THp was
isolated from four healthy male donors and each subjected to
endo-beta-galactosidase treatment in order to release these tetra- and
Sd(a)-active pentasaccharide. Differences were observed in the total amount
of released tetra- and Sda-active pentasaccharide of the used donors (42,
470, 478, 718 microg/100 mg THp), indicating that the presence of repeating
N-acetyllactosamine units incorporated into the N-glycan moiety of THp is
donor specific. Furthermore, a higher expression of the Sd(a) determinant
on antennae which display N-acetyllactosamine elongation was observed,
suggesting a better accessibility for the
beta-N-acetylgalactosaminyltransferase. In order to characterize the
N-glycans containing repeating N- acetyllactosamine units, carbohydrate
chains were enzymatically released from THp and isolated. The
tetraantennary fraction, which accounts for more than 33% of the total
carbohydrate moiety of THp, was used to isolate oligosaccharides containing
additional N - acetyllactosamine units. Five N-linked tetraantennary
oligosaccharides containing a repeating N-acetyllactosamine unit were
identified, varying from structures bearing four Sd(a) determinants to
structures containing no Sd(a) determinant (see below). One compound was
used in order to specify the branch location of the additional N-
acetyllactosamine unit, and it appeared that only the Gal-6' and Gal-8'
residues were occupied by a repeating N -acetyllactosamine unit.
相似文献
77.
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80.
Laurents DV Corrales S Elías-Arnanz M Sevilla P Rico M Padmanabhan S 《Biochemistry》2000,39(45):13963-13973
Folding kinetics for phage 434 Cro protein are examined and compared with those reported for lambda(6-85), the N-terminal domain of the repressor of phage lambda. The two proteins have similar all-helical structures consisting of five helices but different stabilities. In contrast to lambda(6-85), sharp and distinct aromatic (1)H NMR signals without exchange broadening characterize the native and urea-denatured 434 Cro forms at equilibrium at 20 degrees C, indicating slow interconversion on the NMR time scale. Stopped-flow fluorescence data using the single 434 Cro tryptophan indicate strongly urea-dependent refolding rates and smaller urea dependencies of the unfolding rates, suggesting a native-like transition state ensemble. Refolding rates are slower and unfolding rates considerably faster at pH 4 than at pH 6. This accounts for the lower stability of 434 Cro at pH 4 and suggests the existence of pH-dependent, possibly salt bridge interactions that are more stabilizing at pH 6. At <2 M urea, decreased folding amplitudes and nonlinear urea dependencies that are apparent at pH 6 indicate deviation from two-state behavior and suggest the formation of an early folding intermediate. The folding behavior of 434 Cro and why it folds 2 orders of magnitude slower than lambda(6-85) are rationalized in terms of the lower intrinsic helix stabilities and putative charge interactions in 434 Cro. 相似文献