The effect of feeding frequency on growth performance and body composition in juvenile rainbow trout (Oncorhynchus mykiss) reared in cold seawater

This study was done to investigate the effects of different feeding frequencies on the growth, feed efficiency and specific growth rate (%) of juvenile of rainbow trout (Oncorhynchus mykiss, weight 16.44±0.22 g) rearing in cold sea water conditions (5.8 to 9.3°C; 17 to 18 ppt). Fish were fed on a commercial feed to the apparent satiation twice a day (Control), six times every day (TD6), four times every day (TD4) and three times every day (TD3) for 8 weeks of the trial. The fish fed to satiation in all the experimental groups. Weight gain, growth rate, feed intake and final body weight decreased with reduction of feeding frequency from six times daily to two times daily. The fish fed at TD6 had relatively high apparent net protein retention and better feed conversion efficiency compared with the fish fed at the control, TD4 and TD3. The feeding frequency had significant effect on the crude lipid, crude protein but not moisture and crude ash proximate composition of rainbow trout. It was recommended that six meals per day was the optimal feeding frequency for juvenile rainbow trout reared in cold sea water at 5.8 to 9.3°C, 17 to 18 ppt.Key words: Feeding frequencies, growth, body composition, sea water, Oncorhynchus mykiss

A comparison of essential oil components of plants and calli grown in vivo and in vitro conditions of bible hyssop (Origanum syriacum L. var. bevanii (Holmes) Ietswaart)

This research was carried out to determine and compare the essential oil components of regenerated plants and calli grown under in vitro conditions with in vivo plants of Origanum syriacum var. bevanii taxon used as donor. The essential oil components of the donor plants grown with cuttings taken from the native environment and regenerant plants and calli grown from the various explants in vitro supplemented with different concentrations of the plant growth regulators were determined by Gas Chromatography-Mass Spectrometry (GC-MS). In result of the research, it was determined that the essential oil components of donor and regenerant plants and calli were quite different from each other. It was determined that was Carbamic Acid (26.49%) and Carvacrol (19.67%) in essential oil from the regenerant plants while was Carvacrol (36.28%) and ortho-Cymene (19.76%) in essential oil from the donor plants as major components. It was determined that was 64.82% Ethanol, 57.23% 1,2-Propanediol, 55.11% L(+)-Lactic acid, 53.53% Methyltartronic acid, 52.16% 4-Penten-2-ol ve 38.47% 2-Methoxycinnamic acid in essential oil from the callus as major components disparately. 2-Methoxycinnamic acid, which is one of the initial components in the formation of simple phenolic compounds, was found at the highest rate (38.4%) in the callus developed from the stem node explant, compared to the other callus developed from the leaf explant, and constitutes the main component. Therefore, according to the results of the analysis, it was determined that the callus developed from the stem node explant gave promising results in the formation of secondary metabolites

Allelopathic potential of macrofungi on germinating maize (Zea mays L.) grain

The effect of methanol extracts of 10 macrofungi was evaluated on grain germination of maize (Zea mays L.). Germination percentage, radicle and plumule length and the level of carbohydrates and fatty acids were measured. Fungal metabolites inhibited germination up to 90.96%, plumule (97.77%) and radicle (92.83%) development. Plumule and radicle lengths were stimulated 35.26 and 10.60% in some assays, respectively. The fungal metabolites decreased the glucose (97.60%), sucrose (90.34%), fructose (96.85%), maltose (95.64%), oleic acid (97.50%) and linoleic acid (98.25%) levels, whereas increasing levels of the glucose (165.14%), sucrose (166.53%), fructose (83.18%), maltose (124.73%), oleic acid (6975.00%) and linoleic acid (5233.33%) were detected in some assays. It is concluded that macrofungi metabolites have commonly inhibitory effects on physiological and morphological processes of germinating maize grain except for considerable increases in the some parameters investigated

Is neck circumference measurement an indicator for abdominal obesity? A pilot study on Turkish Adults

Background: Neck circumference (NC) measurement is one of the simple screening measurements which can be used as an index of upper body fat distribution to identify obesity.Objectives: The aim of this study was to determine the relationship between neck circumferences and obesity.Methods:A total 411 volunteer adults participated in this study (174 men, 237 women). A questionnaire which consisted of anthropometric measurements and demographic features was used. Patients with NC ≥37 cm for men and ≥34 cm for women require evaluation of overweight status.Results: The percentages of the men and women with BMI ≥ 25kg/m2 were 55.2% and 27.0% respectively and with high neck circumferences were 85.1% and 38.8%, respectively. The percentages of the men and women with high waist circumference were 31.6% and 79.3%, respectively. In both gender there were positive significant correlations between neck circumference, body weight (men, r=0.576; women, r=0.702; p=0.000), waist circumferences (men, r=0.593; women r=0.667; p=0.000), hip circumferences (men, r=0.568; women, r=0.617; p=0.000) and BMI (men, r=0.587; women, r=0.688; p=0.000).Conclusions: This study indicates that NC was associated with body weight, BMI, waist and hip circumferences and waist/hip ratio for men and women. A significant association was found between NC and conventional overweight and obesity indexes. NC was associated with waist/hip ratio for men and women.Key words: Neck circumference, obesity

Analysis of motoneuron responses to composite synaptic volleys (computer simulation study)

This paper deals with the analysis of changes in motoneuron (MN) firing evoked by repetitively applied stimuli aimed toward extracting information about the underlying synaptic volleys. Spike trains were obtained from computer simulations based on a threshold-crossing model of tonically firing MN, subjected to stimulation producing postsynaptic potentials (PSPs) of various parameters. These trains were analyzed as experimental results, using the output measures that were previously shown to be most effective for this purpose: peristimulus time histogram, raster plot and peristimulus time intervalgram. The analysis started from the effects of single excitatory and inhibitory PSPs (EPSPs and IPSPs). The conclusions drawn from this analysis allowed the explanation of the results of more complex synaptic volleys, i.e., combinations of EPSPs and IPSPs, and the formulation of directions for decoding the results of human neurophysiological experiments in which the responses of tonically firing MNs to nerve stimulation are analyzed

Palmitoylation of xanthan polysaccharide for self-assembly microcapsule formation and encapsulation of cells in physiological conditions

Hydrophobized polysaccharides have emerged as a promising strategy in the biomedical field due to the versatility to design functional structures through the spontaneous self-assembly in cell-friendly conditions. Based on this concept, xanthan, a bacterial extracellular polysaccharide with potential as encapsulating matrix, was conjugated with hydrophobic palmitoyl groups to obtain an amphiphilic system able to form capsules by self-assembly processes. The conjugation of xanthan was performed at different xanthan/palmitoyl chloride ratios and Fourier transformed infrared, 1H nuclear magnetic resonance spectroscopies, as well as wide angle X-ray diffraction, differential scanning calorimetry were performed to characterize the obtained conjugates. The results showed that the increase in the hydrophobic reactant promoted higher hydrophobic interaction and consequently higher molecular organization. At certain palmitoyl concentrations and through a proper balance between charge repulsion and hydrophobic interaction, the amphiphilic molecules self-assembled into stable capsular hollow structures in the presence of physiological ion concentration and pH. Poly-L-lysine coated microcapsules with an average diameter of 576.6 _ 74 mm and homogenous size distribution were obtained. The morphology revealed by scanning electron microscopy showed microcapsules with two distinct layers. The ability of palmitoyl-xanthan microcapsules to sustain viability and proliferation of encapsulated cells was confirmed by AlamarBlue and DNA assays. These findings suggest the application of palmitoyl-xanthan microcapsules as a potential material for cell encapsulation in cellbased therapies.This work was supported by the European Union funded project "Find and Bind" (NMP4-SL-2009-229292) under FP7. A. C. Mendes thanks the Portuguese Foundation for Science Technology for a PhD grant (SFRH/BD/42161/2007). We thank Emanuel Fernandes of the 3B's Research Group at the University of Minho for his assistance with DSC analysis

Musculoskeletal sonography in juvenile systemic lupus erythematosus

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Effect of aging on H-reflex response to fatigue

Injury as a result of tripping is relatively common among older people. The risk of falling increases with fatigue and of importance is the ability to dorsiflex the foot through timely activation of the tibialis anterior (TA) muscle to ensure the foot clears the ground, or an obstacle, during the swing phase of walking. We, therefore, questioned whether the muscle spindle input to the motoneurons alters with ongoing fatigue in older people. We electrically stimulated the common peroneal nerve to assess the TA primary afferent efficacy using H-reflex before, immediately following and after a fatiguing maximal isometric contraction. M-response was kept unchanged throughout the experiment to ensure a similar stimulus intensity was delivered across time points. H-reflex increased significantly while the TA muscle was in a state of fatigue for the younger participants but tended to decrease with increasing age. The main contributor to the tonicity of TA muscle, i.e., excitatory synapses of spindle primary endings of motoneurons that innervate TA muscle, tend to lose their efficacy during fatigue in the older individuals but increased efficiency in the majority of the younger people. Since TA muscle is the main dorsiflexor of the foot and it needs to be active during the swing phase of stepping to prevent tripping, older individuals become more susceptible to falling when their muscles are fatigued. This finding may help improve devices/treatments to overcome the problem of tripping among older individuals

Mimicking human neuronal pathways in silico: an emergent model on the effective connectivity

International audienceWe present a novel computational model that detects temporal configurations of a given human neuronal pathway and constructs its artificial replication. This poses a great challenge since direct recordings from individual neurons are impossible in the human central nervous system and therefore the underlying neuronal pathway has to be considered as a black box. For tackling this challenge, we used a branch of complex systems modeling called artificial self-organization in which large sets of software entities interacting locally give rise to bottom-up collective behaviors. The result is an emergent model where each software entity represents an integrate-and-fire neuron. We then applied the model to the reflex responses of single motor units obtained from conscious human subjects. Experimental results show that the model recovers functionality of real human neuronal pathways by comparing it to appropriate surrogate data. What makes the model promising is the fact that, to the best of our knowledge, it is the first realistic model to self-wire an artificial neuronal network by efficiently combining neuroscience with artificial self-organization. Although there is no evidence yet of the model's connectivity mapping onto the human connectivity, we anticipate this model will help neuroscientists to learn much more about human neuronal networks, and could also be used for predicting hypotheses to lead future experiments