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351.
352.
Electrically Assisted Liquid‐Phase Microextraction Combined With Capillary Electrophoresis for Quantification of Propranolol Enantiomers in Human Body Fluids
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Hadi Tabani Ali Reza Fakhari Abolfath Shahsavani Hossein Gharari Alibabaou 《Chirality》2014,26(5):260-267
In this study, electromembrane extraction (EME) combined with cyclodextrin (CD)‐modified capillary electrophoresis (CE) was applied for the extraction, separation, and quantification of propranolol (PRO) enantiomers from biological samples. The PRO enantiomers were extracted from aqueous donor solutions, through a supported liquid membrane (SLM) consisting of 2‐nitrophenyl octyl ether (NPOE) impregnated on the wall of the hollow fiber, and into a 20‐μL acidic aqueous acceptor solution into the lumen of hollow fiber. Important parameters affecting EME efficiency such as extraction voltage, extraction time, pH of the donor and acceptor solutions were optimized using a Box‐Behnken design (BBD). Then, under these optimized conditions, the acceptor solution was analyzed using an optimized CD‐modified CE. Several types of CD were evaluated and best results were obtained using a fused‐silica capillary with ammonium acetate (80 mM, pH 2.5) containing 8 mM hydroxypropyl‐β‐CD as a chiral selector, applied voltage of 18 kV, and temperature of 20°C. The relative recoveries were obtained in the range of 78–95%. Finally, the performance of the present method was evaluated for the extraction and determination of PRO enantiomers in real biological samples. Chirality 26:260–267, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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354.
The control of balance is a primary objective in most human movements. In many cases, research or practice, it is essential to quantitatively know how good the balance is at a body posture or at every moment during a task. In this paper we suggest a new measure for postural upright stability which assigns a value to a body state based on the probability of avoiding a fall initiation from that state. The balance recovery problem is solved for a population sample using a strength database, and the probability of successfully maintaining the balance is found over the population and called the probability of recovery (PoR). It, therefore, describes an attribute of a body state: how possible the control of balance is, or how safe being at that state is. We also show the PoR calculated for a 3-link body model for all states on a plane, compare it to that found using a 2-link model, and compare it to a conventional metric: the margin of stability (MoS). It is shown, for example, that MoS may be very low at a state from which most of the people will be able to easily control their balance. 相似文献
355.
Sonja Hartwig Silja Raschke Birgit Knebel Mika Scheler Martin Irmler Waltraud Passlack Stefan Muller Franz-Georg Hanisch Thomas Franz Xinping Li Hans-Dieter Dicken Kristin Eckardt Johannes Beckers Martin Hrabe de Angelis Cora Weigert Hans-Ulrich Häring Hadi Al-Hasani D. Margriet Ouwens Jürgen Eckel Jorg Kotzka Stefan Lehr 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(5):1011-1017
The skeletal muscle is a metabolically active tissue that secretes various proteins. These so-called myokines have been proposed to affect muscle physiology and to exert systemic effects on other tissues and organs. Yet, changes in the secretory profile may participate in the pathophysiology of metabolic diseases. The present study aimed at characterizing the secretome of differentiated primary human skeletal muscle cells (hSkMC) derived from healthy, adult donors combining three different mass spectrometry based non-targeted approaches as well as one antibody based method. This led to the identification of 548 non-redundant proteins in conditioned media from hSkmc. For 501 proteins, significant mRNA expression could be demonstrated. Applying stringent consecutive filtering using SignalP, SecretomeP and ER_retention signal databases, 305 proteins were assigned as potential myokines of which 12 proteins containing a secretory signal peptide were not previously described. This comprehensive profiling study of the human skeletal muscle secretome expands our knowledge of the composition of the human myokinome and may contribute to our understanding of the role of myokines in multiple biological processes. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge. 相似文献
356.
Leila Farzin Mohammad Esmail Moassesi Fattaneh Sajadi Mojtaba Amiri Hadi Shams 《Biological trace element research》2009,129(1-3):36-45
Zinc (Zn), copper (Cu), and selenium (Se) are well-known as essential trace elements. These elements attract a great interest, not only in the scientific world, but also in the public option. The aim of this study was to evaluate the serum Zn, Cu, and Se levels in healthy volunteers (60 females and 55 males) living in Tehran. The age (6–62 years) and sex of the subjects, as well as drug and tobacco consumption, were registered. The concentrations of these elements were determined by atomic absorption spectrometry. The serum levels of Zn, Cu, and Se in the normal population of Tehran was 0.89?±?0.16 mg/L, 0.95?±?0.20 mg/L, and 99.10?±?21.78 μg/L, respectively. There was no significant gender-related difference in serum Zn concentration (p?<?0.15). However, a significant difference (p?<?0.05) in both Cu and Se levels was observed between males and females. 相似文献
357.
Azarpira N Bagheri M Raisjalali GA Aghdaie MH Behzadi S Salahi H Rahsaz M Darai M Ashraf MJ Geramizadeh B 《Molecular biology reports》2009,36(5):909-915
Despite dramatic improvements in first-year patient and graft survival rates, chronic allograft dysfunction (CAD) remains
the leading cause of late renal allograft loss, while current immunologic strategies have little effect on this condition.
The renin–angiotensin system (RAS) plays an important role in progression of chronic renal disease. It was shown that plasminogen
activator inhibitor-1 (PAI-1) functions in the RAS. This study investigates the possible links between angiotensinogen (AGT
M235T), angiotensin-converting enzyme (ACE) and PAI-1 genotypes with CAD. Assessments of polymorphism were performed in 127
renal allograft recipients (77 with CAD and 50 with normal renal function). Fifty healthy subjects were also considered for
comparison. Genotypes were determined using polymerase chain reaction (PCR) sequence-specific primers and PCR followed by
restriction fragment length polymorphism analysis. Kidney recipients with CAD had significantly higher frequencies of the
TT than the recipients without CAD (P < 0.05). The transplant recipients with CAD also had significantly higher frequencies of the DD genotype than those without
CAD (P < 0.05). No significant differences were observed between the allelic and genotypic distributions of PAI-1 polymorphisms.
Therefore, determination of AGT M235T and ACE genotypes prior to transplantation may be useful to identify patients who are
at risk for chronic renal transplant dysfunction. 相似文献
358.
Northern pike (Esox lucius L.) spermatozoa are uniflagellated cells differentiated into a head without acrosome, a midpiece and a flagellar tail region flanked by a fin structure. Total, flagellar, head and midpiece lengths of spermatozoa were measured and show mean values of 34.5, 32.0, 1.32, 1.17 μm, respectively, with anterior and posterior widths of the midpiece measuring 0.8 and 0.6 μm, respectively. The osmolality of seminal plasma ranged from 228 to 350 mOsmol kg−1 (average: 283.88 ± 33.05). After triggering of sperm motility in very low osmolality medium (distilled water), blebs appeared along the flagellum. At later periods in the motility phase, the tip of the flagellum became curled into a loop shape which resulted in a shortening of the flagellum and a restriction of wave development to the proximal part (close to head). Spermatozoa velocity and percentage of motile spermatozoa decreased rapidly as a function of time postactivation and depended on the osmolality of activation media (P < 0.05). In general, the greatest percentage of motile spermatozoa and highest spermatozoa velocity were observed between 125 and 235 mOsmol kg−1. Osmolality above 375 mOsmol kg−1 inhibited the motility of spermatozoa. After triggering of sperm motility in activation media, beating waves propagated along the full length of flagella, while waves appeared dampened during later periods in the motility phase, and were absent at the end of the motility phase. By increasing osmolality, the velocity of spermatozoa reached the highest value while wave length, amplitude, number of waves and curvatures also were at their highest values. This study showed that sperm morphology can be used for fish classification. Sperm morphology, in particular, the flagellar part showed several changes during activation in distilled water. Sperm motility of pike is inhibited due to high osmolality in the seminal plasma. Osmolality of activation medium affects the percentage of motile sperm and spermatozoa velocity due to changes in flagellar wave parameters. 相似文献
359.
360.
Yuzuru Hamada Nontakorn Urasopon Islamul Hadi Suchinda Malaivijitnond 《International journal of primatology》2006,27(2):497-513
Rhesus (Macaca mulatta) and long-tailed (M. fascicularis) macaques belong to the same species, and are parapatric within a
zone that lies between 15° and 20° N on the Indochinese peninsula. Researchers have reported probable hybrids between the
2 species from that zone, but have not studied the extent of introgression. To test for phenotypic evidence of hybridization,
we collected body mass, morphometrics (body size and proportions), and pelage color readings from free-ranging rhesus living
close to the zonal boundary at Wat Tham Pa Mak Ho (WTPMH), Wang Saphun district, Loei province, northeastern Thailand (17°14′N,
101°47′E). Female WTPMH rhesus macaques (n =12) were 10–20% smaller, but with a greater relative tail length than the captive
Chinese or Indian female rhesus. Female WTPMH were larger than the free-ranging long-tailed macaques, but with similar limb
proportions and a shorter relative tail length. The WTPMH rhesus macaques also displayed the bipartite pelage color pattern
typical of Macaca mulatta . The evidence suggests slight contribution of long-tailed macaques to the gene pool of the WTPMH
population. Further sampling of other macaque populations within the zone and genetic analysis are essential to address better
the question of hybridization. Determination of the distribution and range of biobehavioral variation of macaques within the
zone is urgently needed, because their habitat is being rapidly destroyed by deforestation, and their demography and social
structure are threatened by artificial disturbance. 相似文献