bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brown adipose tissue activation as measured by infrared thermography by mild anticipatory psychological stress in lean healthy females
Authors: Robinson Lindsay J. , Law James M. , Symonds Michael E. , Budge Helen 
Published: February 2016

New Findings

What is the central question of this study?
Does psychological stress, which is known to promote cortisol secretion, simultaneously activate brown adipose tissue function in healthy adult females?

What is the main finding and its importance?
One explanation for the pronounced differences in brown adipose tissue function between individuals lies in their responsiveness to psychological stress and, as such, should be taken into account when examining its in vivo stimulation.

Brown adipose tissue (BAT) has been implicated in the pathogenesis of obesity, type 2 diabetes and the metabolic syndrome and is a potential therapeutic target. Brown adipose tissue can have a significant impact on energy balance and glucose homeostasis through the action of uncoupling protein 1, dissipating chemical energy as heat following neuroendocrine stimulation. We hypothesized that psychological stress, which is known to promote cortisol secretion, would simultaneously activate BAT at thermoneutrality. Brown adipose tissue activity was measured using infrared thermography to determine changes in the temperature of the skin overlying supraclavicular BAT (TSCR). A mild psychological stress was induced in five healthy, lean, female, Caucasian volunteers using a short mental arithmetic (MA) test. The TSCR was compared with a repeated assessment, in which the MA test was replaced with a period of relaxation. Although MA did not elicit an acute stress response, anticipation of MA testing led to an increase in salivary cortisol, indicative of an anticipatory stress response, that was associated with a trend towards higher absolute and relative TSCR. A positive correlation between TSCR and cortisol was found during the anticipatory phase, a relationship that was enhanced by increased cortisol linked to MA. Our findings suggest that subtle changes in the level of psychological stress can stimulate BAT, findings that may account for the high variability and inconsistency in reported BAT prevalence and activity measured by other modalities. Consistent assessment of this uniquely metabolic tissue is fundamental to the discovery of potential therapeutic strategies against metabolic disease.
Reactive oxygen/nitrogen species and contractile function in skeletal muscle during fatigue and recovery
Authors: Cheng Arthur J. , Yamada Takashi , Rassier Dilson E. , Andersson Daniel C. , Westerblad Håkan , Lanner Johanna T. 
Published: February 2016

AbstractThe production of reactive oxygen/nitrogen species (ROS/RNS) is generally considered to increase during physical exercise. Nevertheless, direct measurements of ROS/RNS often show modest increases in ROS/RNS in muscle fibres even during intensive fatiguing stimulation, and the major source(s) of ROS/RNS during exercise is still being debated. In rested muscle fibres, mild and acute exposure to exogenous ROS/RNS generally increases myofibrillar submaximal force, whereas stronger or prolonged exposure has the opposite effect. Endogenous production of ROS/RNS seems to preferentially decrease submaximal force and positive effects of antioxidants are mainly observed during fatigue induced by submaximal contractions. Fatigued muscle fibres frequently enter a prolonged state of reduced submaximal force, which is caused by a ROS/RNS‐dependent decrease in sarcoplasmic reticulum Ca2+ release and/or myofibrillar Ca2+ sensitivity. Increased ROS/RNS production during exercise can also be beneficial and recent human and animal studies show that antioxidant supplementation can hamper the beneficial effects of endurance training. In conclusion, increased ROS/RNS production have both beneficial and detrimental effects on skeletal muscle function and the outcome depends on a combination of factors: the type of ROS/RNS; the magnitude, duration and location of ROS/RNS production; and the defence systems, including both endogenous and exogenous antioxidants.
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Microenvironmental regulation of oligodendrocyte replacement and remyelination in spinal cord injury
Authors: Alizadeh Arsalan , Karimi‐Abdolrezaee Soheila 
Published: February 2016

AbstractMyelin is a proteolipid sheath enwrapping axons in the nervous system that facilitates signal transduction along the axons. In the central nervous system (CNS), oligodendrocytes are specialized glial cells responsible for myelin formation and maintenance. Following spinal cord injury (SCI), oligodendroglia cell death and myelin damage (demyelination) cause chronic axonal damage and irreparable loss of sensory and motor functions. Accumulating evidence shows that replacement of damaged oligodendrocytes and renewal of myelin (remyelination) are promising approaches to prevent axonal degeneration and restore function following SCI. Neural precursor cells (NPCs) and oligodendrocyte progenitor cells (OPCs) are two main resident cell populations in the spinal cord with innate capacities to foster endogenous oligodendrocyte replacement and remyelination. However, due to the hostile microenvironment of SCI, the regenerative capacity of these endogenous precursor cells is conspicuously restricted. Activated resident glia, along with infiltrating immune cells, are among the key modulators of secondary injury mechanisms that create a milieu impermissible to oligodendrocyte differentiation and remyelination. Recent studies have uncovered inhibitory roles for astrocyte‐associated molecules such as matrix chondroitin sulfate proteoglycans (CSPGs), and a plethora of pro‐inflammatory cytokines and neurotoxic factors produced by activated microglia/macrophages. The quality of axonal remyelination is additionally challenged by dysregulation of the supportive growth factors required for maturation of new oligodendrocytes and axo‐oligodendrocyte signalling. Careful understanding of factors that modulate the activity of endogenous precursor cells in the injury microenvironment is a key step in developing efficient repair strategies for remyelination and functional recovery following SCI.
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All‐optical control of cardiac excitation: combined high‐resolution optogenetic actuation and optical mapping
Authors: Entcheva Emilia , Bub Gil 
Published: February 2016

AbstractCardiac tissue is an excitable system that can support complex spatiotemporal dynamics, including instabilities (arrhythmias) with lethal consequences. While over the last two decades optical mapping of excitation (voltage and calcium dynamics) has facilitated the detailed characterization of such arrhythmia events, until recently, no precise tools existed to actively interrogate cardiac dynamics in space and time. In this work, we discuss the combined use of new methods for space‐ and time‐resolved optogenetic actuation and simultaneous fast, high resolution optical imaging of cardiac excitation waves. First, the mechanisms, limitations and unique features of optically induced responses in cardiomyocytes are outlined. These include the ability to bidirectionally control the membrane potential using depolarizing and hyperpolarizing opsins; the ability to induce prolonged sustained voltage changes; and the ability to control refractoriness and the shape of the cardiac action potential. At the syncytial tissue level, we discuss optogenetically enabled experimentation on cell–cell coupling, alteration of conduction properties and termination of propagating waves by light. Specific attention is given to space‐ and time‐resolved application of optical stimulation using dynamic light patterns to perturb ongoing activation and to probe electrophysiological properties at desired tissue locations. The combined use of optical methods to perturb and to observe the system can offer new tools for precise feedback control of cardiac electrical activity, not available previously with pharmacological and electrical stimulation. These new experimental tools for all‐optical electrophysiology allow for a level of precise manipulation and quantification of cardiac dynamics comparable in robustness to the computational setting, and can provide new insights into pacemaking, arrhythmogenesis and suppression or cardioversion.
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Properties of an optogenetic model for olfactory stimulation
Authors: Genovese Federica , Thews Marion , Möhrlen Frank , Frings Stephan 
Published: February 2016

Key points
In olfactory research it is difficult to deliver stimuli with defined intensity and duration to olfactory sensory neurons.
Expression of channelrhodopsin 2 (ChR2) in olfactory sensory neurons provides a means to activate these neurons with light flashes. Appropriate mouse models are available.
The present study explores the suitability of an established olfactory marker protein (OMP)/ChR2–yellow fluorescent protein (YFP) mouse model for ex vivo experimentation.
Expression of ChR2 in sensory neurons of the main olfactory epithelium, the septal organ and vomeronasal organ is characterized. Expression pattern of ChR2 in olfactory receptor neurons and the properties of light responses indicate that light stimulation does not impact on signal transduction in the chemosensory cilia.
Light‐induced electro‐olfactograms are characterized with light flashes of different intensities, durations and frequencies.
The impact of light‐induced afferent stimulation on the olfactory bulb is examined with respect to response amplitude, polarity and low‐pass filtering.
AbstractFor the examination of sensory processing, it is helpful to deliver stimuli in precisely defined temporal and spatial patterns with accurate control of stimulus intensity. This is challenging in experiments with the mammalian olfactory system because airborne odorants have to be transported into the intricate sensory structures of the nose and must dissolve in mucus to be detected by sensory neurons. Defined and reproducible activity can be generated in olfactory sensory neurons that express the light‐gated ion channel channelrhodopsin 2 (ChR2). The neurons can be stimulated by light flashes in a controlled fashion by this optogenetic approach. Here we examined the application of an olfactory marker protein (OMP)/ChR2–yellow fluorescent protein (YFP) model for ex vivo exploration of the olfactory epithelium and the olfactory bulb of the mouse. We studied the expression patterns of ChR2 in the main olfactory system, the vomeronasal system, and the septal organ, and we found that ChR2 is absent from the sensory cilia of olfactory sensory neurons. In the olfactory epithelium, we characterized light‐induced electro‐olfactograms with respect to peripheral encoding of stimulus intensity, stimulus duration and stimulus frequency. In acute slices of the olfactory bulb, we identified specific aspects of the ChR2‐induced input signal, concerning its dynamic range, its low‐pass filter property and its response to prolonged stimulation. Our study describes the performance of the OMP/ChR2–YFP model for ex vivo experimentation on the peripheral olfactory system and documents its versatility and its limitations for olfactory research.
Contour interpolated radial basis functions with spline boundary correction for fast 3D reconstruction of the human articular cartilage from MR images
Authors: Javaid Zarrar , Boocock Mark G. , McNair Peter J. , Unsworth Charles P. 
Published: February 2016

Purpose:The aim of this work is to demonstrate a new image processing technique that can provide a “near real‐time” 3D reconstruction of the articular cartilage of the human knee from MR images which is user friendly. This would serve as a point‐of‐care 3D visualization tool which would benefit a consultant radiologist in the visualization of the human articular cartilage.Methods:The authors introduce a novel fusion of an adaptation of the contour method known as “contour interpolation (CI)” with radial basis functions (RBFs) which they describe as “CI‐RBFs.” The authors also present a spline boundary correction which further enhances volume estimation of the method. A subject cohort consisting of 17 right nonpathological knees (ten female and seven male) is assessed to validate the quality of the proposed method. The authors demonstrate how the CI‐RBF method dramatically reduces the number of data points required for fitting an implicit surface to the entire cartilage, thus, significantly improving the speed of reconstruction over the comparable RBF reconstruction method of Carr. The authors compare the CI‐RBF method volume estimation to a typical commercial package (3d doctor), Carr's RBF method, and a benchmark manual method for the reconstruction of the femoral, tibial, and patellar cartilages.Results:The authors demonstrate how the CI‐RBF method significantly reduces the number of data points (p‐value < 0.0001) required for fitting an implicit surface to the cartilage, by 48%, 31%, and 44% for the patellar, tibial, and femoral cartilages, respectively. Thus, significantly improving the speed of reconstruction (p‐value < 0.0001) by 39%, 40%, and 44% for the patellar, tibial, and femoral cartilages over the comparable RBF model of Carr providing a near real‐time reconstruction of 6.49, 8.88, and 9.43 min for the patellar, tibial, and femoral cartilages, respectively. In addition, it is demonstrated how the CI‐RBF method matches the volume estimation of a typical commercial package (3d doctor), Carr's RBF method, and a benchmark manual method for the reconstruction of the femoral, tibial, and patellar cartilages. Furthermore, the performance of the segmentation method used for the extraction of the femoral, tibial, and patellar cartilages is assessed with a Dice similarity coefficient, sensitivity, and specificity measure providing high agreement to manual segmentation.Conclusions:The CI‐RBF method provides a fast, accurate, and robust 3D model reconstruction that matches Carr's RBF method, 3d doctor, and a manual benchmark method in accuracy and significantly improves upon Carr's RBF method in data requirement and computational speed. In addition, the visualization tool has been designed to quickly segment MR images requiring only four mouse clicks per MR image slice.
Theoretical substantiation of biological efficacy enhancement for β‐delayed particle decay 9C beam: A Monte Carlo study in combination with analysis with the local effect model approach
Authors: Tian Liheng , Li Qiang , Liu Xinguo , Dai Zhongying , Fu Tingyan , He Pengbo , Yan Yuanlin , Ma Yuanyuan , Huang Qiyan 
Published: February 2016

Purpose:To improve the efficacy of heavy ion therapy, β‐delayed particle decay 9C beam as a double irradiation source for cancer therapy has been proposed. The authors' previous experiment showed that relative biological effectiveness (RBE) values at the depths around the Bragg peak of a 9C beam were enhanced and compared to its stable counterpart 12C beam. The purpose of this study was to explore the nature of the biological efficacy enhancement theoretically.Methods:A Monte Carlo simulation study was conducted in this study. First a simplified cell model was established so as to form a tumor tissue. Subsequently, the tumor tissue was imported into the Monte Carlo simulation software package gate and then the tumor cells were virtually irradiated with comparable 9C and 12C beams, respectively, in the simulations. The transportation and particle deposition data of the 9C and 12C beams, derived from the gate simulations, were analyzed with the authors' local effect model implementation so as to deduce cell survival fractions.Results:The particles emitted from the decay process of deposited 9C particles around a cell nucleus increased the dose delivered to the nucleus and elicited clustered damages around the secondary particles' trajectories. Therefore, compared to the 12C beam, the RBE value of the 9C beam increased at the depths around their Bragg peaks.Conclusions:Collectively, the increased local doses and clustered damages due to the decayed particles emitted from deposited 9C particles led to the RBE enhancement in contrast with the 12C beam. Thus, the enhanced RBE effect of a 9C beam for a simplified tumor model was shown theoretically in this study.
Fitness Field Tests’ Correlation With Game Performance in U-19-Category Basketball Referees
Authors: Nabli Mohamed Ali , Abdelkrim Nidhal Ben , Jabri Imed , Batikh Tahar , Castagna Carlo , Chamari Karim 
Published: February 2016

Purpose:To examine the relation between game performance, physiological responses, and field-test results in Tunisian basketball referees.
Methods:Computerized time–motion analysis, heart rate (HR), and blood lactate concentration [La–] were measured in 15 referees during 8 competitive games (under-19-y-old Tunisian league). Referees also performed a repeated-sprint test (RSA), Yo-Yo Intermittent Recovery Test level 1 (YYIRTL1), agility T-test, and 30-m sprint with 10-m lap time. Computerized video analysis determined the time spent in 5 locomotor activities (standing, walking, jogging, running, and sprint), then grouped in high-, moderate-, and low-intensity activities (HIAs, MIAs, and LIAs, respectively).
Results:YYIRTL1 performance correlated with (1) total distance covered during the 4th quarter (r = .52, P = .04) and (2) distance covered in LIA during all game periods (P < .05). Both distance covered and time spent in MIA during the 1st quarter were negatively correlated with the YYIRTL1 performance (r = –.53, P = .035; r = –.67, P = .004, respectively). A negative correlation was found between distance covered at HIA during the 2nd half (3rd quarter + 4th quarter) and fatigue index of the RSA test (r = –.54, P = .029). Mean HR (expressed as %HRpeak) during all game periods was correlated with YYIRTL1 performance (.61 ≤ r < .67, P < .01).
Conclusions:This study showed that (1) the YYIRTL1 performance is a moderate predictor of game physical performance in U-19 basketball referees and (2) referees’ RSA correlates with the amount of HIA performed during the 2nd half, which represents the ability to keep up with play.
An Incremental Shuttle Wheel Test for Wheelchair Tennis Players
Authors: Groot Sonja de , Valent Linda J. , Fickert Richard , Pluim Babette M. , Houdijk Han 
Published: February 2016

Purpose:To determine the relationship between outcomes of the shuttle wheel test (SWT) and peak oxygen uptake (VO2peak) during that test and whether SWT and VO2peak can discriminate between different skill levels of wheelchair tennis players.
Methods:Fifteen wheelchair tennis players performed an SWT on a tennis court while VO2 was measured continuously. Outcome measures were VO2peak and achieved stage. Relations between outcomes and Dutch wheelchair tennis ranking were calculated with Spearman correlation. Independent t tests were used to test for differences between national and international players.
Results:Moderate correlations were found between VO2peak and SWT outcome (r = .40–.47). The tennis ranking correlated weakly with VO2peak (r = –.35) and strongly with SWT outcome (r = –.80). A significant difference was found between national and international players for achieved stage (P = .027) and VO2peak (P = .027).
Conclusions:The SWT outcome only explained a small part of the variance in VO2peak among players, so it cannot be considered a valid test for aerobic capacity. However, SWT outcomes are related to the skill level of the player and give a good indication of the overall peak wheelchair performance.
In Vitro
and
In Vivo
Trypanosomicidal Action of Novel Arylimidamides against Trypanosoma cruzi
Authors: Guedes-da-Silva F. H. , Batista D. G. J. , Meuser M. B. , Demarque K. C. , Fulco T. O. , Araújo J. S. , Da Silva P. B. , Da Silva C. F. , Patrick D. A. , Bakunova S. M. , Bakunov S. A. , Tidwell R. R. , Oliveira G. M. , Britto C. , Moreira O. C. , Soeiro M. N. C. 
Published: February 2016

ABSTRACT

Arylimidamides (AIAs) have been shown to have considerable biological activity against intracellular pathogens, including
Trypanosoma cruzi
, which causes Chagas disease. In the present study, the activities of 12 novel bis-AIAs and 2 mono-AIAs against different strains of
T. cruzi
in vitro
and
in vivo
were analyzed. The most active was
m
-terphenyl bis-AIA (35DAP073), which had a 50% effective concentration (EC
50
) of 0.5 μM for trypomastigotes (Y strain), which made it 26-fold more effective than benznidazole (Bz; 13 μM). It was also active against the Colombiana strain (EC
50
= 3.8 μM). Analysis of the activity against intracellular forms of the Tulahuen strain showed that this bis-AIA (EC
50
= 0.04 μM) was about 100-fold more active than Bz (2 μM). The trypanocidal effect was dissociated from the ability to trigger intracellular lipid bodies within host cells, detected by oil red labeling. Both an active compound (35DAP073) and an inactive compound (26SMB060) displayed similar activation profiles. Due to their high selectivity indexes, two AIAs (35DAP073 and 35DAP081) were moved to
in vivo
studies, but because of the results of acute toxicity assays, 35DAP081 was excluded from the subsequent tests. The findings obtained with 35DAP073 treatment of infections caused by the Y strain revealed that 2 days of therapy induced a dose-dependent action, leading to 96 to 46% reductions in the level of parasitemia. However, the administration of 10 daily doses in animals infected with the Colombiana strain resulted in toxicity, preventing longer periods of treatment. The activity of the combination of 0.5 mg/kg of body weight/day 35DAP073 with 100 mg/kg/day Bz for 10 consecutive days was then assayed. Treatment with the combination resulted in the suppression of parasitemia, the elimination of neurological toxic effects, and survival of 100% of the animals. Quantitative PCR showed a considerable reduction in the parasite load (60%) compared to that achieved with Bz or the amidine alone. Our results support further investigations of this class with the aim of developing novel alternatives for the treatment of Chagas disease.
Dissecting the Structure-Function Relationship of a Fungicidal Peptide Derived from the Constant Region of Human Immunoglobulins
Authors: Ciociola Tecla , Pertinhez Thelma A. , Giovati Laura , Sperindè Martina , Magliani Walter , Ferrari Elena , Gatti Rita , D'Adda Tiziana , Spisni Alberto , Conti Stefania , Polonelli Luciano 
Published: February 2016

ABSTRACT

Synthetic peptides encompassing sequences related to the complementarity-determining regions of antibodies or derived from their constant region (Fc peptides) were proven to exert differential antimicrobial, antiviral, antitumor, and/or immunomodulatory activities
in vitro
and/or
in vivo
, regardless of the specificity and isotype of the parental antibody. Alanine substitution derivatives of these peptides exhibited unaltered, increased, or decreased candidacidal activities
in vitro
. The bioactive IgG-derived Fc N10K peptide (NQVSLTCLVK) spontaneously self-assembles, a feature previously recognized as relevant for the therapeutic activity of another antibody-derived peptide. We evaluated the contribution of each residue to the peptide self-assembling capability by circular-dichroism spectroscopy. The interaction of the N10K peptide and its derivatives with
Candida albicans
cells was studied by confocal, transmission, and scanning electron microscopy. The apoptosis and autophagy induction profiles in yeast cells treated with the peptides were evaluated by flow cytometry, and the therapeutic efficacy against candidal infection was studied in a
Galleria mellonella
model. Overall, the results indicate a critical role for some residues in the self-assembly process and a correlation of that capability with the candidacidal activities of the peptides
in vitro
and their therapeutic effects
in vivo
.