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61.
Clemens Wittenbecher Romina di Giuseppe Ronald Biemann Juliane Menzel Maria Arregui Juliane Hoffmann Krasimira Aleksandrova Heiner Boeing Berend Isermann Matthias B. Schulze Cornelia Weikert 《PloS one》2015,10(9)
The reliability of single time point measurements of the novel adipokines retinol-binding protein 4 and omentin-1 in the blood has not been evaluated in large samples yet. The present study aimed to assess the amount of biological variation of these two adipokines within individuals. The study sample comprised 207 participants (124 women and 83 men) from Potsdam (Germany) and surrounding areas, with an average age of 56.5 years (SD 4.2). Blood samples were collected from each participant twice, approximately four months apart. Using enzyme linked immunosorbent assays, the concentrations of retinol-binding protein 4 and omentin-1 were determined in EDTA plasma. As indicators of reliability, intraclass correlation coefficients (ICCs) were calculated from the repeated biomarker measurements. The ICCs for repeated retinol-binding protein 4 and omentin-1 measurements were 0.77 (95% CI 0.71, 0.82) and 0.83 (95% CI 0.78, 0.87), respectively, indicating for both adipokines excellent reliability. ICCs were stable across strata according to sex, age, BMI, and blood pressure. Thus, for epidemiological studies it seems reasonable to rely on concentrations of retinol-binding protein 4 and omentin-1 in samples from a single time point if repeated measurements are not available. 相似文献
62.
S. S. Terekhov T. V. Bobik Yu. A. Mokrushina A. V. Stepanova N. M. Aleksandrova I. V. Smirnov A. A. Belogurov N. A. Ponomarenko A. G. Gabibov 《Applied Biochemistry and Microbiology》2016,52(2):162-169
A platform for the cloning and expression of active human butyrylcholinesterase (BuChE) in the yeast Pichia рastoris is first presented. Genetic constructs for BuChE gene expression, separately and in conjunction with a proline-rich peptide called proline-rich attachment domain (PRAD), are based on the vector pPICZαA. It is shown that the highest level of production is achieved in the expression of a BuChE gene without PRAD pPICZαA. It is found that one can obtain up to 125 mg of active enzyme from 1 L of culture medium at an optimal pH environment (pH 7.6), an optical seed culture density of 3 o.u., and an optimum methanol addition mode of (0.5% methanol in the first day and 0.2% thereafter from the second day). 相似文献
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66.
D. V. Grishin D. D. Zhdanov Ju. A. Gladilina V. S. Pokrovsky O. V. Podobed M. V. Pokrovskaya S. S. Aleksandrova A. L. Milyushkina M. A. Vigovskiy N. N. Sokolov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2018,12(2):143-150
In this work, a recombinant chemotaxis CheW protein from Thermotoga petrophila RKU-1 (TpeCheW) and its mutant homologue (TpeCheW-mut) have been obtained. Despite the low homology with the CheW protein of the Escherichia coli bacteria, these proteins do not cause metabolic overload and are well expressed by E. coli laboratory strains. A wide range of features and parameters important for isolation of the TpeCheW-mut protein, such as stability over a wide range of temperatures and pH values, high level of expression, solubility, and the possibility of using simple low-stage purification schemes, including heat pretreatment, has been recognized. Possible directions of using this protein in the practice of scientific and applied research have been formulated and justified. 相似文献
67.
R. Daraktchiev V. Beschkov N. Kolev T. Aleksandrova 《Bioprocess and biosystems engineering》1997,16(2):115-117
The bioreactor with a semi-fixed packing consists of frames with stretched “Raschell”-type sacks on them. This construction enables the attainment of a larger interfacial area of the biofilm carrier per unit reactor volume as well as the easy removal of the exausted biomass at certain biofilm thickness. In the present paper the batch anaerobic conversion of lactose to lactic acid in this reactor with immobilized bacteria Lactobacillus casei is studied. The dilution rate of the feeding substrate solution was 1?mm/s. Comparison of our experimental results with data, obtained for free cells and other construction of bioreactors with immobilized cells is made. It is shown that the used immobilised biocatalyst is superior to free bacterial cells, or attached to the inner pores of polyurethane foam. 相似文献
68.
Relationships among msx gene structure and function in zebrafish and other vertebrates 总被引:6,自引:2,他引:4
Ekker M; Akimenko MA; Allende ML; Smith R; Drouin G; Langille RM; Weinberg ES; Westerfield M 《Molecular biology and evolution》1997,14(10):1008-1022
The zebrafish genome contains at least five msx homeobox genes, msxA, msxB,
msxC, msxD, and the newly isolated msxE. Although these genes share
structural features common to all Msx genes, phylogenetic analyses of
protein sequences indicate that the msx genes from zebrafish are not
orthologous to the Msx1 and Msx2 genes of mammals, birds, and amphibians.
The zebrafish msxB and msxC are more closely related to each other and to
the mouse Msx3. Similarly, although the combinatorial expression of the
zebrafish msx genes in the embryonic dorsal neuroectoderm, visceral arches,
fins, and sensory organs suggests functional similarities with the Msx
genes of other vertebrates, differences in the expression patterns preclude
precise assignment of orthological relationships. Distinct duplication
events may have given rise to the msx genes of modern fish and other
vertebrate lineages whereas many aspects of msx gene functions during
embryonic development have been preserved.
相似文献
69.
E L Riabkova G K Reshed'ko E D Agapova I A Aleksandrova N V Beloborodova T Iu Vostrikova D E Zdzitovetski? S F Ivanova V N Il'ina N E Marusina I G Multykh S V Polikarpova S V Skal'ski? T N Suborova I A Toropova V B Turkutiukov 《Antibiotiki i khimioterapii͡a》2005,50(8-9):43-51
Prevalence of Klebsiella pneumoniae among gramnegative pathogens of nosocomial infections in intensive care units of 33 hospitals of 22 towns in Russia was investigated. Antibiotic susceptibility and extended-spectrum beta-lactamase production were tested in 420 nosocomial K. pneumoniae isolates. Carbapenems (imipenem, meropenem and ertapenem) showed the highest activity. Extended-spectrum beta-lactamase production based on the phenotyping methods was revealed in 342 (81.4%) isolates. The maximum activity against the K. pneumoniae isolates producing extended-spectrum beta-lactamase was observed in imipenem and meropenem (no unsusceptible strains were isolated). 3.2% of the isolates was not susceptible to ertapenem. Differences in the activity of cefoperazone/sulbactam, amikacin, ciprofloxacin and levofloxacin against the extended-spectrum beta-lactamase producing isolates in various hospitals were recorded. 相似文献
70.
RICARDO BONFIM-SILVA LARISSA OLIVEIRA GUIMARÃES JANDSON SOUZA SANTOS JAQUELINE FAGUNDES PEREIRA ANA ANGÉLICA LEAL BARBOSA DOMINGOS LAZARO SOUZA RIOS 《Journal of genetics》2016,95(1):63-69
The rennin–angiotensin–aldosterone system (RAAS) is a critical pathway in regulating blood pressure and salt/water homeostasis, possessing an intimate relationship with the development of systemic artery hypertension (SAH). Once hypertension is considered a risk factor for coronary artery disease (CAD), the RAAS is also related to this pathology. This investigation aimed to analyse if the frequencies of AGT M235T (rs699) and ACE I/D (rs4646994) polymorphisms are associated with CAD and SAH in African-Brazilians and Caucasian-Brazilians. In this study we analysed 714 subjects who underwent coronary angiography to detect obstructive lesions and CAD, as well as blood pressure measurement and SAH, grouped according to ethnicity: 266 African-Brazilians and 448 Caucasian-Brazilians. Among CAD and SAH cases and controls, the genotype and allele frequencies of ACE I/D polymorphism were similar in both ethnic groups. The AGT 235TT genotype and 235T allele frequencies were higher in SAH cases (32%, 54.7%) versus controls in Caucasian-Brazilians (19.8%, 46.4%; P= 0.038, P= 0.031, respectively). The AGT 235TT (OR = 1.8; P= 0.028) demonstrated to be an independent factor risk in a multivariate logistic regression increasing SAH risk in Caucasians but not in African-Brazilians. In summary, AGT M235T polymorphism was associated with SAH risk in Caucasian-Brazilians, and no association was detected with CAD. No association was also observed in ACE I/D polymorphism either in CAD or SAH in African-Brazilians and Caucasian-Brazilians. 相似文献