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41.
F. Fazio C. Saoca S. Casella G. Fortino G. Piccione 《Marine and Freshwater Behaviour and Physiology》2013,45(4):289-296
The aim of this study was to evaluate the possible correlation between biometric indices (length and weight) and some blood parameters in 225 Gilthead sea bream (Sparus aurata) and 225 European sea bass (Dicentrarchus labrax) cultured in onshore tanks with the same physical–chemical conditions of water (temperature, soluble oxygen and salinity). From each fish, blood samples were collected to evaluate Red Blood Cell Count, Haematocrit, Haemoglobin Concentration, White Blood Cell Count, Thrombocyte Count, Mean Corpuscular Volume, Mean Corpuscular Haemoglobin and Mean Corpuscular Haemoglobin Concentration, glucose, lactate and Total Proteins. In both species, the relationship between the biometric indices and blood parameters was evaluated using linear regression analysis that showed a statistically significant correlation between the biometric indices and seven of the studied parameters. These results showed that fish size is an important factor in the interpretation of haematological and biochemical profiles in order to evaluate correctly the health status of the fish. 相似文献
42.
Bee Ting Chan Einly Lim Chi Wei Ong Noor Azuan Abu Osman 《Computer methods in biomechanics and biomedical engineering》2013,16(1):90-96
Despite the advancement of cardiac imaging technologies, these have traditionally been limited to global geometrical measurements. Computational fluid dynamics (CFD) has emerged as a reliable tool that provides flow ?eld information and other variables essential for the assessment of the cardiac function. Extensive studies have shown that vortex formation and propagation during the filling phase acts as a promising indicator for the diagnosis of the cardiac health condition. Proper setting of the boundary conditions is crucial in a CFD study as they are important determinants, that affect the simulation results. In this article, the effect of different transmitral velocity profiles (parabolic and uniform profile) on the vortex formation patterns during diastole was studied in a ventricle with dilated cardiomyopathy (DCM). The resulting vortex evolution pattern using the uniform inlet velocity profile agreed with that reported in the literature, which revealed an increase in thrombus risk in a ventricle with DCM. However the application of a parabolic velocity profile at the inlet yields a deviated vortical flow pattern and overestimates the propagation velocity of the vortex ring towards the apex of the ventricle. This study highlighted that uniform inlet velocity profile should be applied in the study of the filling dynamics in a left ventricle because it produces results closer to that observed experimentally. 相似文献
43.
44.
Dr Julio J. Ochoa Francisco Contreras-Chova Sergio Muñoz Eduardo Araujo-Nepomuceno Antonio Bonillo Antonio Molina-Carballo 《Free radical research》2013,47(9):1035-1040
Objective: To study the evolution of lipid peroxidation, enzymatic antioxidants response, lipid profile and membrane fluidity in erythrocytes from very low birth weight (VLBW) infants during their first 7 days of extra-uterine life.Study design: One hundred and twenty infants were selected and divided in two groups according to their weight and gestational age. Hydroperoxides, fatty-acid profile, fluidity (DPH and TMA-DPH) and catalase, SOD and GPx activities were measured in erythrocytes.Results: VLBW group showed higher concentration of hydroperoxides and lower membrane fluidity during the first 72 h, lower SOD activity during the first 3 h and higher GPx activity during the first 7 days of life. Also, this group showed lower n-3 polyunsaturated fatty-acids percentage with respect to the term group.Conclusion: Erythrocytes from VLBW infants showed higher oxidative damage and lower fluidity in their membranes, at least during the first 3 days of extra-uterine life, which may cause alterations in their functions and flexibility. 相似文献
45.
《Free radical research》2013,47(9):710-717
AbstractThe protecting ability of the Piper betle leaves-derived phenol, allylpyrocatechol (APC) against AAPH-induced membrane damage of human red blood cells (RBCs) was investigated. Compared to control, AAPH (50 mM) treatment resulted in significant hemolysis (55%, p < 0.01), associated with increased malondialdehyde (MDA) (2.9-fold, p < 0.001) and methemoglobin (6.1-fold, p < 0.001) levels. The structural deformation due to membrane damage was confirmed from scanning electron microscopy (SEM) images and Heinz bodies formation, while the cell permeability was evident from the K+ efflux (28.7%, p < 0.05) and increased intracellular Na+ concentration (8%, p < 0.05). The membrane damage, due to the reduction of the cholesterol/phospholipids ratio and depletion (p < 0.001) of ATP, 2,3-DPG by ?44–54% and Na+–K+ ATPase activity (43.7%), indicated loss of RBC functionality. The adverse effects of AAPH on all these biochemical parameters and the resultant oxidative hemolysis of RBCs were significantly reduced by pretreating the cells with APC (7 μM) or α-tocopherol (50 μM) for 1 h, prior to incubation with AAPH. 相似文献
46.
Susan C. Connor Mark P. Hodson Stephanie Ringeissen Brian C. Sweatman Paul J. Mcgill Catherine J. Waterfield 《Biomarkers》2013,18(4-5):364-385
A previous report of this work (Ringeissen et al. 2003) described the use of nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistical data analysis (MVDA) to identify novel biomarkers of peroxisome proliferation (PP) in Wistar Han rats. Two potential biomarkers of peroxisome proliferation in the rat were described, N-methylnicotinamide (NMN) and N-methyl-4-pyridone-3-carboxamide (4PY). The inference from these results was that the tryptophan-nicotinamide adenine dinucleotide (NAD+) pathway was altered in correlation with peroxisome proliferation, a hypothesis subsequently confirmed by TaqMan® analysis of the relevant genes encoding two key enzymes in the pathway, aminocarboxymuconate-semialdehyde decarboxylase (EC 4.1.1.45) and quinolinate phosphoribosyltransferase (EC 2.4.2.19). The objective of the present study was to investigate these data further and identify other metabolites in the NMR spectrum correlating equally with PP. MVDA Partial Least Squares (PLS) models were constructed that provided a better prediction of PP in Wistar Han rats than levels of 4PY and NMN alone. The resulting Wistar Han rat predictive models were then used to predict PP in a test group of Sprague Dawley rats following administration of fenofibrate. The models predicted the presence or absence of PP (above on arbitrary threshold of >2-fold mean control) in all Sprague Dawley rats in the test group. 相似文献
47.
Sang Myung Lee Seok Chang Kim Joonseok Oh Jin Hee Kim MinKyun Na 《Phytochemistry letters》2013,6(4):620-624
In spite of the general concept that herbal supplements are safe, there is a lack of appropriate quality control measures and regulations that often culminates in serious undesirable effects such as allergic reactions and renal and liver damage. Thus, there is a growing need to establish a suitable methodology that enables authentication and quality assurance of herbal products. The root of Panax ginseng C. A. Meyer (Araliaceae), commonly called ginseng, is traditionally recognized as a prominent herbal medicine in Far East Asia. There are two types of processed ginseng, white and red ginseng, based on processing methods, and these play a significant role in modifying ginsenosides, which are the major bioactive metabolites in these products. Herein we purify and characterize a new ginsenoside, 20(R)-ginsenoside Rf, utilizing NMR, UPLC-ESI-Q-TOF-MS and validate the metabolite is generated from its epimer, 20(S)-ginsenoside Rf during the steaming process to manufacture red ginseng. We further propose a relevant mechanism for the chemical conversion. This finding updates chemical profiling of ginseng products that can be employed in quality assurance and authentication. 相似文献
48.
Andrew K. Schmucker Nicholas Scott Johnson Ugo Bussy Ke Li Heather S. Galbraith Yu-Wen Chung-Davidson Weiming Li 《Journal of fish biology》2020,96(4):1024-1033
The American eel (Anguilla rostrata) is an imperilled fish hypothesized to use conspecific cues, in part, to coordinate long-distance migration during their multistage life history. Here, holding water and tissue from multiple American eel life stages was collected and analysed for the presence, profile and concentration of bile acids. Distinct bile acid profiles were identified in glass, elver, yellow eel and silver eel holding waters using ultraperformance liquid chromatography high-resolution mass spectrometry and principal component analysis. Taurochenodeoxycholic acid, taurodeoxycholic acid, cholic acid, deoxycholic acid, taurolithocholic acid and taurocholic acid were detected in whole tissue of American glass eels and elvers, and in liver, intestine and gallbladder samples of late-stage yellow eels. Bile acids were not a major component of silver eel washings or tissue. This study is novel because little was previously known about bile acids produced and emitted into the environment by American eels. Future behavioural studies could evaluate whether any bile acids produced by American eels influence conspecific migratory behaviour. 相似文献
49.
The mesic Caspian (Hyrcanian) forest and ecotone communities provide a marked contrast to the arid and semiarid landscapes associated with most of the territory of Iran. To date, the ecological characteristics of these habitats, threatened and of conservation importance, have been little studied. Accordingly, ecological profiles of some important plant species of these communities have been assessed along two altitudinal gradients (300–2300 m a.s.l.). Vegetation and soils were sampled every 100 m in elevation, with the data subsequently analyzed using TWINSPAN and corrected frequency (CF) analyses. Relationships between soil variables (subdivided into three classes, the lowest, the middle and the upper third of all values) and herbaceous and shrub species (presence/absence data) were analyzed by the polythetic divisive classification method. 379 plant species and eleven soil variables – N, P, K, CaCO3, EC, pH, organic matter, C/N ratio and percentage of sand, clay and silt – were considered. The ecological profile method was used to evaluate the affinity and significance of associations between the probability of species’ occurrence and topsoil characteristics found by the polythetic method. Five vegetation groups were identified: two groups, with Acer campestre and Quercus macranthera in the tree layer and Veronica mazanderanae and Phuopsis stylosa as herbs, were restricted to forest-steppe ecotones and the upper mountain areas. Three groups, with Acer velutinum, Ruscus hyrcanus, Carpinus betulus, Danae racemosa, Fagus orientalis and Aruncus vulgaris as indicator species, occurred in the forest itself. Of the 42 plant species assessed as being of particular importance, 13 had significant relationships with eight soil factors. Thus, certain species, including endemic plant species of restricted distribution and conservation importance, can be used as indicators of particular soil conditions in the Hyrcanian forest area. 相似文献
50.
《Chronobiology international》2013,30(4):397-407
The purpose was to assess age-related circadian changes of blood pressure profile (BPP) employing a truncated Fourier series with four harmonics (tFs) in patients with essential hypertension. The study was performed on 32 patients with essential hypertension divided in two groups: (A) 15 patients younger than 55 years and (B) 17 patients older than 60 years. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored every 20 minutes for 24h with a noninvasive portable device (SpaceLabs 90202). To evaluate the existence of SBP and DBP circadian rhythms a one-sample runs-test was performed and the mesor, amplitude, and acrophase from the overall curve of each patient were obtained by tFs. In both groups, SBP and DBP profiles showed a first peak in the late morning and a second peak in the early evening around the same hours. The two peaks in the SBP profile were higher and the two peaks in the DBP profile were lower in older patients than in younger ones (p. 01, p <. 05, p>. 3, p>. 05). The truncated Fourier series with four harmonics evidences different age-related BP profiles characterized by two peaks with higher SBP and lower DBP in elderly patients. These changes of BPP are in accordance with the reported higher risk of cardiovascular events observed around the same hours. (Chronobiology International, 14(4), 397–407, 1997) 相似文献