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31.
32.
Molecular evolution of rodent insulins 总被引:1,自引:0,他引:1
Several trees of amino acid sequences of rodent insulins were derived with
the maximum-parsimony procedure. Possible orthologous and paralogous
relationships were investigated. Except for a recent gene duplication in
the ancestor of rat and mouse, there are no strong arguments for other
paralogous relationships. Therefore, a tree in agreement with other
biological data is the most reasonable one. According to this tree, the
capacity to form zinc-binding hexamers was lost once in the ancestor of the
hystricomorph rodents, followed by moderately increased evolutionary rates
in the lineages to African porcupine and chinchilla but highly increased
rates in at least three independent lines to other taxa of this suborder:
guinea pig, cuis, and Octodontoidea (coypu and casiragua).
相似文献
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34.
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35.
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36.
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
37.
Laurent Rivet Gilbert Mille Anne Basseres Alain Ladousse Claude Gerin Monique Acquaviva Jean-Claude Bertrand 《Biotechnology letters》1993,15(6):637-640
Summary Hexadecane biodegradation by a marine bacterium has been investigated in the presence of an oleophilic nutriment (INIPOL EAP 22). Hydrocarbon attack was only observed after metabolism of the fatty acids present in the fertilizer. The bacterium used up 95 % fatty acids in the first 24 hours. Hexadecane biodegradation took place after 50 h incubation and reached 40 % after 360 h. 相似文献
38.
Purification and specificity of bacteriolytic enzyme I from Hartmannella glebae. 总被引:1,自引:1,他引:0 下载免费PDF全文
A soil amoeba (Hartmannella glebae), when grown in conjunction with Enterobacter aerogenes and Alcaligenes faecalis, produced two enzymes. Enzyme I was purified by gel filtration on Sephadex G-100 and chromatography on diethylaminoethyl-cellulose. It is a basic protein. The analysis of the enzymic digest of the cell walls of Micrococcus lysodeikticus after reduction and acid hydrolysis showed that the enzyme cleaved the glycosidic bond between acetylmuramic acid and acetylglucosamine of the peptidoglycan moiety of the cell walls. The enzyme is identified as endo-beta-N-acetylmuramidase. 相似文献
39.
40.