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The influence of physical activity on body mass components has been studied using a sample of Moscow children. 195 girls and 259 boys of Russian ethnicity from 12 to 17 years old were investigated cross-sectionally in 2005 in different Moscow schools. According to the level of physical activity they were divided into three groups: 1-those who did not take part in regular physical exercise (44 boys and 50 girls); 2-those who took part in special sports programs in general education schools (82 boys and 82 girls); 3-students of special sports schools with a high sports ranking (133 boys and 63 girls). The program included anthropometric measurements, evaluation of sexual maturation indices, somatotypes, and "functional" traits (diastolic and systolic blood pressure, pulse rate, hand grip, etc). For the study of body composition, bioelectrical impedance analysis (BIA) was used. The estimates of body mass components were also calculated using the anthropometric measurements. For the fat component, the estimates obtained by BIA and the anthropometric methods were highly correlated: r=0.85-0.88. Age changes of BIA measurements and body components were analysed. With multiple regression analysis it was shown that BIA measurements are dependent on a great number of morphological and functional traits, with the most informative sets of traits being selected. The degree of physical activity has a strong effect on body components: the contents of fat-free mass (FFM) and total body water (TBW) significantly increase, and the fat mass (FM) in girls decreases.  相似文献   
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More than half of the mutations of the amyloid precursor protein (APP) discovered in familiar forms of Alzheimer’s disease are located in the transmembrane domain. The pathogenic mutations presumably affect the lateral dimerization of the APP transmembrane domain in the membrane and change the dimer conformation and/or stability. Thus, the mutations cause an alternative APP digestion pattern in the membrane and neurotoxic amyloid β-peptide generation. For the detailed study of the specific protein-protein and protein-lipid interactions of the APP transmembrane domain, an E. coli recombinant expression construct was made. The recombinant protein contains an APP transmembrane domain (APPtm(686–726)) with adjacent extramembrane N and C ends. Here, we report the method of isotope-labeled APPtm expression and purification in quantities necessary for a heteronuclear NMR spectroscopy structure and dynamics study. On the basis of the 1H-15N-HSQC spectra, we developed APPtm(686–726) solubilization conditions in the membrane-emulated milieu detergent micelles and lipid bicelles.  相似文献   
35.
Depth Profilometry involves the measurement of the depth profile of objects, and has significant potential for various industrial applications that benefit from non-destructive sub-surface profiling such as defect detection, corrosion assessment, and dental assessment to name a few. In this study, we investigate the feasibility of depth profilometry using an Multiplexed Optical High-coherence Interferometry MOHI instrument. The MOHI instrument utilizes the spatial coherence of a laser and the interferometric properties of light to probe the reflectivity as a function of depth of a sample. The axial and lateral resolutions, as well as imaging depth, are decoupled in the MOHI instrument. The MOHI instrument is capable of multiplexing interferometric measurements into 480 one-dimensional interferograms at a location on the sample and is built with axial and lateral resolutions of 40 μm at a maximum imaging depth of 700 μm. Preliminary results, where a piece of sand-blasted aluminum, an NBK7 glass piece, and an optical phantom were successfully probed using the MOHI instrument to produce depth profiles, demonstrate the feasibility of such an instrument for performing depth profilometry.  相似文献   
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Extremely acidic copper-containing proteins, neurocupreins, were isolated from brains of various mammals (bovine, rabbit, pig and sheep). Neurocupreins from all these sources were found to have similar physico-chemical and antigenic properties. Using the immunological approach, it was shown that neurocuprein is located only in brain cytosol and synaptosomal fractions. Extremely acidic copper-containing proteins were also isolated from soluble and membranous fractions of chromaffin granules from bovine adrenal medulla. The soluble form of the protein from the granules has practically the same physico-chemical and antigenic properties as neurocupreins. The copper protein isolated from membranes of granules has slightly higher molecular weight and somewhat different amino acid composition, although their EPR spectra are identical. However, both copper proteins from chromaffin granules are immunoprecipitated with antibodies to neurocuprein. It is suggested that the membranous form differs from the soluble one in possessing a peptide which prolongs the protein chain without changes in its antigenic properties.  相似文献   
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We study the opto‐electrical properties of Natronomonas pharaonis sensory rhodopsin II (NpSRII) by using a near‐field microwave microprobe (NFMM) under external light illumination. To investigate the possibility of application of NFMM to biological macromolecules, we used time dependent properties of NPSRII before/after light activation which has three distinct states – ground‐state, M‐state, and O‐state. The diagnostic ability of NFMM is demonstrated by measuring the microwave reflection coefficient (S11) spectrum of NpSRII under steady‐state illumination in the wavelength range of 350–650 nm. Moreover, we present microwave reflection coefficient S11 spectra in the same wavelength range for two fast‐photocycling rhodopsins: green light‐absorbing proteorhodopsin (GPR) and Gloeobacter rhodopsin (GR). In addition the frequency sweep shift can be detected completely even for tiny amounts of sample (~10–3 OD of rhodopsin). Based on these results NFMM shows both very high sensitivity for detecting conformational changes and produces a good time‐resolved spectrum. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
38.

Background

To evaluate association between von Willebrand factor (vWF) activity, inflammation markers, disease activity, and subclinical atherosclerosis in patients with rheumatoid arthritis (RA) and low cardiovascular risk.

Methods

Above mentioned parameters were determined in blood samples of 74 non-diabetic, normotensive, female subjects, with no dyslipidemia(42 patients, 32 matched healthy controls, age 45.3±10.0 vs. 45.2±9.8 years). Intima-media thickness (IMT) was measured bilaterally, at common carotid, bifurcation, and internal carotid arteries. Subclinical atherosclerosis was defined as IMT>IMTmean+2SD in controlsat each carotid level and atherosclerotic plaque as IMT>1.5 mm. Majority of RA patients were on methotrexate (83.3%), none on steroids >10 mg/day or biologic drugs. All findings were analysed in the entire study population and in RA group separately.

Results

RA patients with subclinical atherosclerosis had higher vWF activity than those without (133.5±69.3% vs. 95.3±36.8%, p<0.05). Predictive value of vWF activity for subclinical atherosclerosis was confirmed by logistic regression. vWF activity correlated significantly with erythrocyte sedimentation rate, fibrinogen, modified disease activity scores (mDAS28–ESR, mDAS28–CRP), modified Health Assessment Questionnaire (p<0.01 for all), duration of smoking, number of cigarettes/day, rheumatoid factor concentration (p<0.05 for all), and anti-CCP antibodies (p<0.01). In the entire study population, vWF activity was higher in participants with subclinical atherosclerosis (130±68% vs. 97±38%, p<0.05) or atherosclerotic plaques (123±57% vs. 99±45%, p<0.05) than in those without. Duration of smoking was significantly associated with vWF activity (β 0.026, p = 0.039).

Conclusions

We demonstrated association of vWF activity and subclinical atherosclerosis in low-risk RA patients as well as its correlation with inflammation markers, all parameters of disease activity, and seropositivity. Therefore, vWF might be a valuable marker of early atherosclerosis in RA patients.  相似文献   
39.
Telomeres are the ends of eukaryotic chromosomes, consisting of consecutive short repeats that protect chromosome ends from degradation. Telomeres shorten with each cell division, leading to replicative cell senescence. Deregulation of telomere length homeostasis is associated with the development of various age-related diseases and cancers. A number of experimental techniques exist for telomere length measurement; however, until recently, the absence of tools for extracting telomere lengths from high-throughput sequencing data has significantly obscured the association of telomere length with molecular processes in normal and diseased conditions. We have developed Computel, a program in R for computing mean telomere length from whole-genome next-generation sequencing data. Computel is open source, and is freely available at https://github.com/lilit-nersisyan/computel. It utilizes a short-read alignment-based approach and integrates various popular tools for sequencing data analysis. We validated it with synthetic and experimental data, and compared its performance with the previously available software. The results have shown that Computel outperforms existing software in accuracy, independence of results from sequencing conditions, stability against inherent sequencing errors, and better ability to distinguish pure telomeric sequences from interstitial telomeric repeats. By providing a highly reliable methodology for determining telomere lengths from whole-genome sequencing data, Computel should help to elucidate the role of telomeres in cellular health and disease.  相似文献   
40.
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