bluuebunny/crossref_metadata_2025 huggingface dataset:
Time-Motion and Biological Responses in Simulated Mixed Martial Arts Sparring Matches
Authors: Coswig Victor S. , Ramos Solange de P. , Del Vecchio Fabrício B.
Published: January 2016

Coswig, VS, Ramos, SdP, and Del Vecchio, FB. Time-motion and biological responses in simulated mixed martial arts sparring matches. J Strength Cond Res 30(8): 2156–2163, 2016—Simulated matches are a relevant component of training for mixed martial arts (MMA) athletes. This study aimed to characterize time-motion responses and investigate physiological stress and neuromuscular changes related to MMA sparring matches. Thirteen athletes with an average age of 25 ± 5 years, body mass of 81.3 ± 9.5 kg, height of 176.2 ± 5.5 cm, and time of practice in MMA of 39 ± 25 months participated in the study. The fighters executed three 5-minute rounds with 1-minute intervals. Blood and salivary samples were collected and physical tests and psychometric questionnaires administered at 3 time points: before (PRE), immediately after (POST), and 48 hours after the combat (48 h). Statistical analysis applied analysis of variance for repeated measurements. In biochemical analysis, significant changes (p ≤ 0.05) were identified between PRE and POST (glucose: 80.3 ± 12.7 to 156.5 ± 19.1 mg·ml−1; lactate: 4 ± 1.7 to 15.6 ± 4.8 mmol·dl−1), POST and 48 hours (glucose: 156.5 ± 19.1 to 87.6 ± 15.5 mg·ml−1; lactate: 15.6 ± 4.8 to 2.9 ± 3.5 mmol·dl−1; urea: 44.1 ± 8.9 to 36.3 ± 7.8 mg·ml−1), and PRE and 48 hours (creatine kinase [CK]: 255.8 ± 137.4 to 395.9 ± 188.7 U/L). In addition, time-motion analyses showed a total high:low intensity of 1:2 and an effort:pause ratio of 1:3. In conclusion, simulated MMA sparring matches feature moderate to high intensity and a low degree of musculoskeletal damage, which can be seen by absence of physical performance and decrease in CK. Results of the study indicate that sparring training could be introduced into competitive microcycles to improve technical and tactical aspects of MMA matches, due to the high motor specificity and low muscle damage.
Contribution of Upper-Body Strength, Body Composition, and Maximal Oxygen Uptake to Predict Double Poling Power and Overall Performance in Female Cross-Country Skiers
Authors: Østerås Sindre , Welde Boye , Danielsen Jørgen , van den Tillaar Roland , Ettema Gertjan , Sandbakk Øyvind
Published: January 2016

Østerås, S, Welde, B, Danielsen, J, van den Tillaar, R, Ettema, G, and Sandbakk, Ø. Contribution of upper-body strength, body composition, and maximal oxygen uptake to predict double poling power and overall performance in female cross-country skiers.J Strength Cond Res30(9): 2557–2564, 2016—Maximal oxygen uptake (V̇o2max) is regarded as the most performance-differentiating physiological measure in cross-country (XC) skiing. In addition, upper-body strength and lean mass have been associated with double poling (DP) power in XC skiers. In this study, we tested upper-body maximal strength, lean mass, and V̇o2max's contributions to predict DP power production of different durations and the overall XC skiing performance level of elite female XC skiers. Thirteen skiers (V̇o2max: 64.9 ± 4.2 ml·kg−1·min−1) performed one 30-second and one 3-minute DP performance test using a ski ergometer. The International Ski Federation's (FIS) ranking points determined their overall XC skiing performance. The skiers performed three 1-repetition maximal strength tests in poling-specific exercises that isolated the elbow extension, shoulder extension, and trunk flexion movements. Body composition was determined by a DXA scan, and V̇o2max was tested in an incremental running test. Multiple regressions were used to predict power production in the 30-second and 3-minute tests and FIS points. The 2 best predictions of 30-second DP power were lean upper-body mass and maximal upper-body strength (with the 3 strength tests normalized and pooled together as one variable) (R2= 0.84 and 0.81,p< 0.001). Along with V̇o2max, the same 2 variables were the best predictions of both 3-minute DP power (R2= 0.60 and 0.44,p≤ 0.05) and overall XC skiing performance (R2= 0.43 and 0.40,p≤ 0.05). Although the importance of upper-body strength and lean mass to predict DP power production and the overall XC skiing performance declines with the performance duration in female XC skiers, the importance of V̇o2max shows an opposite relationship.
Adaptation to Damaging Dance and Repeated-Sprint Activity in Women
Authors: Brown Meghan A. , Howatson Glyn , Keane Karen M. , Stevenson Emma J.
Published: January 2016

Brown, MA, Howatson, G, Keane, KM, and Stevenson, EJ. Adaptation to damaging dance and repeated-sprint activity in women. J Strength Cond Res 30(9): 2574–2581, 2016—The repeated bout effect (RBE) refers to the prophylactic effect from damaging exercise after a single previous bout of exercise. There is a paucity of data examining the RBE in women, and investigations using exercise paradigms beyond isolated eccentric contractions are scarce. In light of the limited literature, this investigation aimed to determine whether 2 different sport-specific exercise bouts would elicit a RBE in women. Twenty-one female dancers (19 ± 1 years) completed either a dance-specific protocol (n = 10) or sport-specific repeated-sprint protocol (n = 11). Delayed-onset muscle soreness (DOMS), limb girths, creatine kinase (CK), countermovement jump height, reactive strength index, maximal voluntary contraction, and 30-meter sprint time were recorded before and 0, 24, 48, and 72 hours after exercise. An identical exercise bout was conducted approximately 4 weeks after the initial bout, during which time the subjects maintained habitual training and dietary behaviors. DOMS and 30-meter sprint time decreased after a second bout of both activities (p = 0.003;

JOURNAL/jscr/04.03/00124278-201609000-00027/inline-formula1/v/2023-08-19T002706Z/r/image-tiff

= 0.38 and p = 0.008; and

JOURNAL/jscr/04.03/00124278-201609000-00027/inline-formula2/v/2023-08-19T002706Z/r/image-tiff

= 0.31, respectively). Circulating CK was also lower at 24, 48, and 72 hours after the second bout, independent of group (p = 0.010 and

JOURNAL/jscr/04.03/00124278-201609000-00027/inline-formula3/v/2023-08-19T002706Z/r/image-tiff

= 0.23). Compared with the repeated-sprint protocol, the magnitude of change in DOMS was greater after a subsequent bout of the dance protocol (p = 0.010 and

JOURNAL/jscr/04.03/00124278-201609000-00027/inline-formula4/v/2023-08-19T002706Z/r/image-tiff

= 0.19). These data are the first to demonstrate that dance and repeated-sprint activity resulting in muscle damage in women confers a protective effect against muscle damage after a subsequent bout.
Physical Performance of Brazilian Rugby Players From Different Age Categories and Competitive Levels
Authors: Kobal Ronaldo , Nakamura Fábio Y. , Moraes José E. , Coelho Maurício , Kitamura Katia , Cal Abad Cesar C. , Pereira Lucas A. , Loturco Irineu
Published: January 2016

Kobal, R, Nakamura, FY, Moraes, JE, Coelho, M, Kitamura, K, Cal Abad, CC, Pereira, LA, and Loturco, I. Physical performance of Brazilian rugby players from different age categories and competitive levels. J Strength Cond Res 30(9): 2433–2439, 2016—The aim of this study was to compare the anthropometric characteristics and physical capacities (vertical jumping, speed, agility, and endurance abilities) among different age categories of Brazilian rugby players from the same high-level club and to compare their respective data with those obtained from the national team players. Eighty-eight men Brazilian rugby players from 4 different age categories were divided into 4 different groups (i.e., under-15 [U-15], under-17 [U-17], under-19 [U-19], and professional senior team [PRO]) and a group composed of players from the Brazilian national team (NAT). Anthropometric measures (i.e., height and body mass), squat jump (SJ) and countermovement jump (CMJ) tests , 2 agility tests (change of direction [COD] and proagility), 40-m sprinting, and the Yo-Yo endurance test (level 1) were compared among the groups using an analysis of covariance (multivariable multivariate analysis of covariance) with the body mass as a covariate. The NAT group demonstrated significantly greater performances in all variables compared with the U-15, U-17, U-19, and PRO groups (p ≤ 0.05). Moreover, the PRO group demonstrated better performances in vertical jumping assessments (i.e., SJs and CMJs) and agility tests (i.e., COD and proagility) than the younger categories (p ≤ 0.05). Finally, except for the U-15 group, no significant differences were found between the young age-categories in sprint and endurance capacities. These findings show that, throughout the maturation process, rugby players improve their muscle power and agility abilities without presenting significant increases in endurance and sprinting capacities. Importantly, this does not hold true for players from the NAT group, who presented superior performance in all assessed physical variables (in comparison with the younger age and PRO categories).
Accumulation of Laminin Monomers inDrosophilaGlia Leads to Glial Endoplasmic Reticulum Stress and Disrupted Larval Locomotion
Authors: Petley-Ragan Lindsay M. , Ardiel Evan L. , Rankin Catharine H. , Auld Vanessa J.
Published: January 2016

The nervous system is surrounded by an extracellular matrix composed of large glycoproteins, including perlecan, collagens, and laminins. Glial cells in many organisms secrete laminin, a large heterotrimeric protein consisting of an α, β, and γ subunit. Prior studies have found that loss of laminin subunits from vertebrate Schwann cells causes loss of myelination and neuropathies, results attributed to loss of laminin-receptor signaling. We demonstrate that loss of the laminin γ subunit (LanB2) in the peripheral glia ofDrosophila melanogasterresults in the disruption of glial morphology due to disruption of laminin secretion. Specifically, knockdown of LanB2 in peripheral glia results in accumulation of the β subunit (LanB1), leading to distended endoplasmic reticulum (ER), ER stress, and glial swelling. The physiological consequences of disruption of laminin secretion in glia included decreased larval locomotion and ultimately lethality. Loss of the γ subunit from wrapping glia resulted in a disruption in the glial ensheathment of axons but surprisingly did not affect animal locomotion. We found that Tango1, a protein thought to exclusively mediate collagen secretion, is also important for laminin secretion in glia via a collagen-independent mechanism. However loss of secretion of the laminin trimer does not disrupt animal locomotion. Rather, it is the loss of one subunit that leads to deleterious consequences through the accumulation of the remaining subunits.

SIGNIFICANCE STATEMENTThis research presents a new perspective on how mutations in the extracellular matrix protein laminin cause severe consequences in glial wrapping and function. Glial-specific loss of the β or γ laminin subunit disrupted glia morphology and led to ER expansion and stress due to retention of other subunits. The retention of the unpaired laminin subunit was key to the glial disruption as loss of Tango1 blocked secretion of the complete laminin trimer but did not lead to glial or locomotion defects. The effects were observed in the perineurial glia that envelope the peripheral and central nervous systems, providing evidence for the importance of this class of glia in supporting nervous system function.
Why Don't We Move Slower? The Value of Time in the Neural Control of Action
Authors: Berret Bastien , Jean Frédéric
Published: January 2016

To want something now rather than later is a common attitude that reflects the brain's tendency to value the passage of time. Because the time taken to accomplish an action inevitably delays task achievement and reward acquisition, this idea was ported to neural movement control within the “cost of time” theory. This theory provides a normative framework to account for the underpinnings of movement time formation within the brain and the origin of a self-selected pace in human and animal motion. Then, how does the brain exactly value time in the control of action? To tackle this issue, we used an inverse optimal control approach and developed a general methodology allowing to squarely sample infinitesimal values of the time cost from experimental motion data. The cost of time underlying saccades was found to have a concave growth, thereby confirming previous results on hyperbolic reward discounting, yet without making any prior assumption about this hypothetical nature. For self-paced reaching, however, movement time was primarily valued according to a striking sigmoidal shape; its rate of change consistently presented a steep rise before a maximum was reached and a slower decay was observed. Theoretical properties of uniqueness and robustness of the inferred time cost were established for the class of problems under investigation, thus reinforcing the significance of the present findings. These results may offer a unique opportunity to uncover how the brain values the passage of time in healthy and pathological motor control and shed new light on the processes underlying action invigoration.

SIGNIFICANCE STATEMENTMovement time is a fundamental characteristic of neural motor control, but the principles underlying its formation remain little known. This work addresses that question within the inverse optimal control framework where the challenge is to uncover what optimality criterion underlies a system's behavior. Here we rely on the “cost of time” theory that finds its roots into the brain's tendency to discount the actual value of future reward. It asserts that the time elapsed until action completion entails a cost, thereby making slow moves nonoptimal. By means of a thorough theoretical analysis, the present article shows how to sample the infinitesimal values of the time cost without prior assumption about its hypothetical nature and emphasizes its sigmoidal shape for reaching.
Obesity Weighs down Memory through a Mechanism Involving the Neuroepigenetic Dysregulation of Sirt1
Authors: Heyward Frankie D. , Gilliam Daniel , Coleman Mark A. , Gavin Cristin F. , Wang Jing , Kaas Garrett , Trieu Richard , Lewis John , Moulden Jerome , Sweatt J. David
Published: January 2016

Aberrant gene expression within the hippocampus has recently been implicated in the pathogenesis of obesity-induced memory impairment. Whether a dysregulation of epigenetic modifications mediates this disruption in gene transcription has yet to be established. Here we report evidence of obesity-induced alterations in DNA methylation of memory-associated genes, including Sirtuin 1 (Sirt1), within the hippocampus, and thus offer a novel mechanism by which SIRT1 expression within the hippocampus is suppressed during obesity. Forebrain neuron-specificSirt1knock-out closely recapitulated the memory deficits exhibited by obese mice, consistent with the hypothesis that the high-fat diet-mediated reduction of hippocampal SIRT1 could be responsible for obesity-linked memory impairment. Obese mice fed a diet supplemented with the SIRT1-activating molecule resveratrol exhibited increased hippocampal SIRT1 activity and preserved hippocampus-dependent memory, further strengthening this conclusion. Thus, our findings suggest that the memory-impairing effects of diet-induced obesity may potentially be mediated by neuroepigenetic dysregulation of SIRT1 within the hippocampus.

SIGNIFICANCE STATEMENTPrevious studies have implicated transcriptional dysregulation within the hippocampus as being a relevant pathological concomitant of obesity-induced memory impairment, yet a deeper understanding of the basis for, and etiological significance of, transcriptional dysregulation in this context is lacking. Here we present the first evidence of epigenetic dysregulation (i.e., altered DNA methylation and hydroxymethylation) of memory-related genes, includingSirt1, within the hippocampus of obese mice. Furthermore, experiments using transgenic and pharmacological approaches strongly implicate reduced hippocampal SIRT1 as being a principal pathogenic mediator of obesity-induced memory impairment. This paper offers a novel working model that may serve as a conceptual basis for the development of therapeutic interventions for obesity-induced memory impairment.
Microsaccades Are Coupled to Heartbeat
Authors: Ohl Sven , Wohltat Christian , Kliegl Reinhold , Pollatos Olga , Engbert Ralf
Published: January 2016

During visual fixation, the eye generates microsaccades and slower components of fixational eye movements that are part of the visual processing strategy in humans. Here, we show that ongoing heartbeat is coupled to temporal rate variations in the generation of microsaccades. Using coregistration of eye recording and ECG in humans, we tested the hypothesis that microsaccade onsets are coupled to the relative phase of the R-R intervals in heartbeats. We observed significantly more microsaccades during the early phase after the R peak in the ECG. This form of coupling between heartbeat and eye movements was substantiated by the additional finding of a coupling between heart phase and motion activity in slow fixational eye movements; i.e., retinal image slip caused by physiological drift. Our findings therefore demonstrate a coupling of the oculomotor system and ongoing heartbeat, which provides further evidence for bodily influences on visuomotor functioning.

SIGNIFICANCE STATEMENTIn the present study, we show that microsaccades are coupled to heartbeat. Moreover, we revealed a strong modulation of slow eye movements around the R peak in the ECG. These results suggest that heartbeat as a basic physiological signal is related to statistical modulations of fixational eye movements, in particular, the generation of microsaccades. Therefore, our findings add a new perspective on the principles underlying the generation of fixational eye movements. Importantly, our study highlights the need to record eye movements when studying the influence of heartbeat in neuroscience to avoid misinterpretation of eye-movement-related artifacts as heart-evoked modulations of neural processing.
Age-Related Phasic Patterns of Mitochondrial Maintenance in AdultCaenorhabditis elegansNeurons
Authors: Morsci Natalia S. , Hall David H. , Driscoll Monica , Sheng Zu-Hang
Published: January 2016

Aging is associated with cognitive decline and increasing risk of neurodegeneration. Perturbation of mitochondrial function, dynamics, and trafficking are implicated in the pathogenesis of several age-associated neurodegenerative diseases. Despite this fundamental importance, the critical understanding of how organismal aging affects lifetime neuronal mitochondrial maintenance remains unknown, particularly in a physiologically relevant context. To address this issue, we performed a comprehensivein vivoanalysis of age-associated changes in mitochondrial morphology, density, trafficking, and stress resistance in individualCaenorhabditis elegansneurons throughout adult life. Adult neurons display three distinct stages of increase, maintenance, and decrease in mitochondrial size and density during adulthood. Mitochondrial trafficking in the distal neuronal processes declines progressively with age starting from early adulthood. In contrast, long-liveddaf-2mutants exhibit delayed age-associated changes in mitochondrial morphology, constant mitochondrial density, and maintained trafficking rates during adulthood. Reduced mitochondrial load at late adulthood correlates with decreased mitochondrial resistance to oxidative stress. Revealing aging-associated changes in neuronal mitochondriain vivois an essential precedent that will allow future elucidation of the mechanistic causes of mitochondrial aging. Thus, our study establishes the critical foundation for the future analysis of cellular pathways and genetic and pharmacological factors regulating mitochondrial maintenance in aging- and disease-relevant conditions.

SIGNIFICANCE STATEMENTUsingCaenorhabditis elegansas a model, we address long-standing questions: How does aging affect neuronal mitochondrial morphology, density, trafficking, and oxidative stress resistance? Are these age-related changes amenable to genetic manipulations that slow down the aging process? Our study illustrates that mitochondrial trafficking declines progressively from the first day of adulthood, whereas mitochondrial size, density, and resistance to oxidative stress undergo three distinct stages: increase in early adulthood, maintenance at high levels during mid-adulthood, and decline during late adulthood. Thus, our study characterizes mitochondrial aging profile at the level of a single neuron in its native environment and establishes the critical foundation for the future genetic and pharmacological dissection of factors that influence long-term mitochondrial maintenance in neurons.
Activation of PPARγ Ameliorates Spatial Cognitive Deficits through Restoring Expression of AMPA Receptors in Seipin Knock-Out Mice
Authors: Zhou Libin , Chen Tingting , Li Guoxi , Wu Chaoming , Wang Conghui , Li Lin , Sha Sha , Chen Lei , Liu George , Chen Ling
Published: January 2016

A characteristic phenotype of congenital generalized lipodystrophy 2 (CGL2) that is caused by loss-of-function of seipin gene is mental retardation. Here, we show that seipin deficiency in hippocampal CA1 pyramidal cells caused the reduction of peroxisome proliferator-activated receptor gamma (PPARγ). Twelve-week-old systemicseipinknock-out mice and neuronalseipinknock-out (seipin-nKO) mice, but not adiposeseipinknock-out mice, exhibited spatial cognitive deficits as assessed by the Morris water maze and Y-maze, which were ameliorated by the treatment with the PPARγ agonist rosiglitazone (rosi). In addition,seipin-nKO mice showed the synaptic dysfunction and the impairment of NMDA receptor-dependent LTP in hippocampal CA1 regions. The density of AMPA-induced current (IAMPA) in CA1 pyramidal cells and GluR1/GluR2 expression were significantly reduced inseipin-nKO mice, whereas the NMDA-induced current (INMDA) and NR1/NR2 expression were not altered. Rosi treatment inseipin-nKO mice could correct the decrease in expression and activity of AMPA receptor (AMPAR) and was accompanied by recovered synaptic function and LTP induction. Furthermore, hippocampal ERK2 and CREB phosphorylation inseipin-nKO mice were reduced and this could be rescued by rosi treatment. Rosi treatment inseipin-nKO mice elevated BDNF concentration. The MEK inhibitor U0126 blocked rosi-restored AMPAR expression and LTP induction inseipin-nKO mice, but the Trk family inhibitor K252a did not. These findings indicate that the neuronal seipin deficiency selectively suppresses AMPAR expression through reducing ERK-CREB activities, leading to the impairment of LTP and spatial memory, which can be rescued by PPARγ activation.

SIGNIFICANCE STATEMENTCongenital generalized lipodystrophy 2 (CGL2), caused by loss-of-function mutation of seipin gene, is characterized by mental retardation. By the generation of systemic or neuronalseipinknock-out mice, the present study providesin vivoevidence that neuronal seipin deficiency causes deficits in spatial memory and hippocampal LTP induction. Neuronal seipin deficiency selectively suppresses AMPA receptor expression, ERK-CREB phosphorylation with the decline of PPARγ. The PPARγ agonist rosiglitazone can ameliorate spatial cognitive deficits and rescue the LTP induction inseipinknock-out mice by restoring AMPA receptor expression and ERK-CREB activities.
AP-1 Transcription Factors Mediate BDNF-Positive Feedback Loop in Cortical Neurons
Authors: Tuvikene Jürgen , Pruunsild Priit , Orav Ester , Esvald Eli-Eelika , Timmusk Tõnis
Published: January 2016

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, regulates both survival and differentiation of several neuronal populations in the nervous system during development, as well as synaptic plasticity in the adult brain. BDNF exerts its biological functions through its receptor TrkB. Although the regulation ofBDNFtranscription by neuronal activity has been widely studied, little is known about TrkB signaling-dependent expression ofBDNF. Using rat primary cortical neuron cultures, we show that theBDNFgene is a subject to an extensive autoregulatory loop, where TrkB signaling upregulates the expression of all majorBDNFtranscripts, mainly through activating MAPK pathways. Investigating the mechanisms behind this autoregulation, we found that AP-1 transcription factors, comprising Jun and Fos family members, participate in the induction ofBDNFexon I, III, and VI transcripts. AP-1 transcription factors directly upregulate the expression of exon I transcripts by binding two novel AP-1cis-elements in promoter I. Moreover, our results show that the effect of AP-1 proteins on the activity of ratBDNFpromoters III and VI is indirect, because AP-1 proteins were not detected to bind the respective promoter regions by chromatin immunoprecipitation (ChIP). Collectively, we describe an extensive positive feedback system inBDNFregulation, adding a new layer to the elaborate control ofBDNFgene expression.

SIGNIFICANCE STATEMENTHere, we show for the first time that in rat primary cortical neurons the expression of all majorBDNFtranscripts (exon I, II, III, IV, VI, and IXa transcripts) is upregulated in response to TrkB signaling, and that AP-1 transcription factors participate in the induction of exon I, III, and VI transcripts. Moreover, we have described two novel functional AP-1cis-elements inBDNFpromoter I, responsible for the activation of the promoter in response to TrkB signaling. Our results indicate the existence of a positive feedback loop for obtaining sufficient BDNF levels necessary for various TrkB signaling-dependent physiological outcomes in neurons.
Equivalent Activities of Repulsive Axon Guidance Receptors
Authors: Long Hong , Yoshikawa Shingo , Thomas John B.
Published: January 2016

Receptors on the growth cone at the leading edge of elongating axons play critical guidance roles by recognizing cues via their extracellular domains and transducing signals via their intracellular domains, resulting in changes in direction of growth. An important concept to have emerged in the axon guidance field is the importance of repulsion as a major guidance mechanism. Given the number and variety of different repulsive receptors, it is generally thought that there are likely to be qualitative differences in the signals they transduce. However, the nature of these possible differences is unknown. By creating chimeras using the extracellular and intracellular domains of three differentDrosophilarepulsive receptors, Unc5, Roundabout (Robo), and Derailed (Drl) and expressing them in defined cells within the embryonic nervous system, we examined the responses elicited by their intracellular domains systematically. Surprisingly, we found no qualitative differences in growth cone response or axon growth, suggesting that, despite their highly diverged sequences, each intracellular domain elicits repulsion via a common pathway. In terms of the signaling pathway(s) used by the repulsive receptors, mutations in the guanine nucleotide exchange factor Trio strongly enhance the repulsive activity of all three intracellular domains, suggesting that repulsion by Unc5, Robo, and Drl, and perhaps repulsion in general, involves Trio activity.

SIGNIFICANCE STATEMENTA prevailing concept that has emerged in the axon guidance field is the importance of repulsion as a guidance mechanism for steering axons to their appropriate targets. Given the number and variety of different repulsive receptors, it is generally thought that there are differences in the signals that they transduce. However, this has never been tested directly. We have used the advanced genetics ofDrosophilato compare directly the outputs of different repulsive receptors. Surprisingly, we found no qualitative differences in receptor-mediated repulsion, suggesting that, despite their highly diverged domain structure, each receptor couples to a common repulsive pathway. We went on to show that this common pathway involves Trio, a guanine nucleotide exchange factor known to promote cytoskeletal remodeling.
Transcranial Stimulation of the Dorsolateral Prefrontal Cortex Prevents Stress-Induced Working Memory Deficits
Authors: Bogdanov Mario , Schwabe Lars
Published: January 2016

Stress is known to impair working memory performance. This disruptive effect of stress on working memory has been linked to a decrease in the activity of the dorsolateral prefrontal cortex (dlPFC). In the present experiment, we tested whether transcranial direct current stimulation (tDCS) of the dlPFC can prevent stress-induced working memory impairments. We tested 120 healthy participants in a 2 d, sham-controlled, double-blind between-subjects design. Participants completed a test of their individual baseline working memory capacity on day 1. On day 2, participants were exposed to either a stressor or a control manipulation before they performed a visuospatial and a verbal working memory task. While participants completed the tasks, anodal, cathodal, or sham tDCS was applied over the right dlPFC. Stress impaired working memory performance in both tasks, albeit to a lesser extent in the verbal compared with the visuospatial working memory task. This stress-induced working memory impairment was prevented by anodal, but not sham or cathodal, stimulation of the dlPFC. Compared with sham or cathodal stimulation, anodal tDCS led to significantly better working memory performance in both tasks after stress. Our findings indicate a causal role of the dlPFC in working memory impairments after acute stress and point to anodal tDCS as a promising tool to reduce cognitive deficits related to working memory in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder.

SIGNIFICANCE STATEMENTWorking memory deficits are prominent in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder. Similar working memory impairments have been observed in healthy individuals exposed to acute stress. So far, attempts to prevent such stress-induced working memory deficits focused mainly on pharmacological interventions. Here, we tested the idea that transcranial direct current stimulation of the dorsolateral prefrontal cortex (dlPFC), a critical neural substrate of working memory, may prevent working memory impairments after stress. Our results indicate that anodal stimulation of the dlPFC may indeed preserve working memory performance under stress, suggesting that the dlPFC plays a causal role in stress-induced working memory deficits and pointing to a potential new avenue to prevent stress-induced cognitive impairments.
Neuropeptide Y Impairs Retrieval of Extinguished Fear and Modulates Excitability of Neurons in the Infralimbic Prefrontal Cortex
Authors: Vollmer Lauren L. , Schmeltzer Sarah , Schurdak Jennifer , Ahlbrand Rebecca , Rush Jennifer , Dolgas Charles M. , Baccei Mark L. , Sah Renu
Published: January 2016

Neuropeptide Y (NPY), a 36 aa peptide, regulates stress and emotional behaviors. Preclinical and clinical studies support an association of NPY with trauma-evoked syndromes such as posttraumatic stress disorder (PTSD), although the exact contribution of NPY is not clear. In the current study, we examined functional attributes of NPY in the infralimbic (IL) cortex, an area that regulates fear memories and is reported to be hypoactive in PTSD. Carriers of NPY gene polymorphism rs16147 have been reported to have elevated prefrontal NPY expression. Infusion of NPY into the IL cortex in rats significantly impaired fear extinction memory without affecting conditioned fear expression or acquisition of extinction. Neuroendocrine stress response, depression-like behavior, and working memory performance were not affected by NPY infusion into the IL. The NPY Y1receptor antagonist BIBO3304 completely abolished NPY effects on fear extinction retrieval. Y1receptor expression was localized on CaMKII-positive pyramidal projection neurons and GAD67-positive interneurons in the IL. Patch-clamp recordings revealed increased inhibitory synaptic transmission onto IL projection neurons in the presence of NPY. Thus, NPY dampens excitability of IL projection neurons and impairs retrieval of extinction memory by inhibiting consolidation of extinction. Of relevance to PTSD, elevation of prefrontal NPY attributable to the genetic polymorphism rs16147 may contribute to IL hypoactivity, resulting in impaired extinction memory and susceptibility to the disorder.

SIGNIFICANCE STATEMENTNeuropeptide Y (NPY), a stress modulatory transmitter, is associated with posttraumatic stress disorder (PTSD). Contribution of NPY to PTSD symptomology is unclear. PTSD patients have reduced activity in the infralimbic (IL) subdivision of the medial prefrontal cortex (mPFC), associated with compromised extinction memory. No information exists on fear modulation by NPY in the IL cortex, although NPY and NPY receptors are abundant in these areas. This study shows that IL NPY inhibits consolidation of extinction, resulting in impaired retrieval of extinction memory and modulates excitability of IL projection neurons. In addition to providing a novel perspective on extinction memory modulation by NPY, our findings suggest that elevated mPFC NPY in gene polymorphism rs16147 carriers or after chronic stress could increase susceptibility to PTSD.
Islam Indonesia dan Demokratisasi: Dari Transisi ke Konsolidasi
Authors: Testriono Testriono
Published: January 2016

Mirjam Kunkler and Alfred Stepan (eds). 2013. Democracy and Islam in Indonesia. New York: Columbia University Press. xv + 252pp.Donald L. Horowitz. 2013. Constitutional Change and Democracy in Indonesia. Cambridge: Cambridge University Press. xviii + 326pp.The two reviewed books provide explanations for the success of Indonesia’s democratization. Kunkler and Stepan’s (2013) edited volume, Democracy and Islam in Indonesia, emphasizes the political actors (agency) in explaining democratization in Indonesia. Meanwhile, Horowitz’s (2013) Constitutional Change and Democracy in Indonesia focuses on institutions and the strategies of institutional reform chosen by political actors during democratization. Both works provide careful evaluation on the relatively stable development of Indonesian democracy. Examining the social, political, and institutional foundations that facilitate the consolidation of Indonesia’s democracy, the two works analyze why and how the democratic transition in Indonesia proceeded to a consolidation stage. Different form Kunkler and Stepan’s edited volume, which evaluates the state of Indonesian democracy by refererring to the criteria offered by democratic consolidation framework, Horowitz’s work moves farther revealing why the democratic processes have occurred in the sequence and manner that they did.DOI: 10.15408/sdi.v22i3.2411
Hereditary Angioedema Presenting as Recurrent Acute Pancreatitis
Authors: Berger Tal D. , Garty Ben-Zion
Published: January 2016

Hereditary angioedema (HAE) may manifest with swelling of the face, extremities, and upper airways. Gastrointestinal symptoms are also common and may include abdominal pain, vomiting, and diarrhea. However, pancreatic involvement is rare and has been reported only in a few adults with previously diagnosed HAE. We describe a 6-year-old boy who presented with recurrent severe abdominal pain accompanied by an elevation in pancreatic enzyme levels, without subcutaneous or cutaneous angioedema. His symptoms had begun 18 months earlier, and he was hospitalized several times before the present admission with a diagnosis of acute pancreatitis. More comprehensive analysis yielded low levels of C2, C4, CH50, and C1 esterase inhibitor, establishing the diagnosis of HAE. One year after diagnosis, swelling of the extremities appeared for the first time. This is the first report of a child in whom pancreatic disease was the presenting symptom of HAE. HAE should be included in the differential diagnosis of recurrent pancreatitis in children.
Stakeholder Views of Clinical Trials in Low- and Middle-Income Countries: A Systematic Review
Authors: Joseph Pathma D. , Caldwell Patrina H.Y. , Tong Allison , Hanson Camilla S. , Craig Jonathan C.
Published: January 2016

CONTEXT:

Clinical trials are necessary to improve the health care of children, but only one-quarter are conducted in the low- to middle-income countries (LMICs) in which 98% of the global burden of disease resides.

OBJECTIVE:

To describe stakeholder beliefs and experiences of conducting trials in children in LMICs.

DATA SOURCES:

Electronic databases were searched to August 2014.

STUDY SELECTION:

Qualitative studies of stakeholder perspectives on conducting clinical trials among children in LMICs.

DATA EXTRACTION:

Findingswere analyzed by using thematic synthesis.

RESULTS:

Thirty-nine studies involving 3110 participants (children [n = 290], parents or caregivers [n = 1609], community representatives [n = 621], clinical or research team members [n = 376], regulators [n = 18], or sponsors [n = 15]) across 22 countries were included. Five themes were identified: centrality of community engagement (mobilizing community, representatives’ pivotal role, managing expectations, and retaining involvement); cognizance of vulnerability and poverty (therapeutic opportunity and medical mistrust); contending with power differentials (exploitation, stigmatization, and disempowerment); translating research to local context (cultural beliefs, impoverishment constraints, and ethical pluralism); and advocating fair distribution of benefits (health care, sponsor obligation, and collateral community benefits).

LIMITATIONS:

Studies not published in English were excluded.

CONCLUSIONS:

Conducting trials in children in LMICs is complex due to social disadvantage, economic scarcity, idiosyncratic cultural beliefs, and historical disempowerment, all of which contribute to inequity, mistrust, and fears of exploitation. Effective community engagement in recruiting, building research capacities, and designing trials that are pragmatic, ethical, and relevant to the health care needs of children in LMICs may help to improve the equity and health outcomes of this vulnerable population.
Ablation of Arrhythmias in Patients with Adult Congenital Heart Disease
Authors: Lobo Rodrigo Gallardo , Griffith Michael , De Bono Joseph ,   Senior Fellow in Electrophysiology,   Consultant Cardiologist, Queen Elizabeth Hospital, Birmingham, UK,   Consultant Cardiologist, Queen Elizabeth Hospital, Queen Elizabeth Medical Centre, Birmingham B15 2TH, UK. E: Joseph.DeBono@uhb.nhs.uk
Published: January 2016

Arrhythmias in adults with congenital heart disease, most commonly related to previous surgical procedures, are a frequent comorbidity in this growing population thanks to the improved outcome of surgical techniques. Re-entrant circuits around areas of scarring and natural barriers, combined with abnormal haemodynamics and the underlying anatomy, are the most common cause for these arrhythmias. They are often poorly tolerated and medical treatment is frequently inadequate. In recent years, catheter ablation has emerged as a successful therapeutic option. New advanced techniques such as the use of modern three-dimensional (3D) navigation systems have contributed to better understanding of the arrhythmia mechanisms and higher success rates of the ablation procedures. In this article we briefly summarise the characteristics of the most common arrhythmias in this patient population and some key aspects in their treatment by catheter ablation.
Trade Models in the Study of Agricultural Origins and Dispersals
Authors: Runnels Curtis
Published: January 2016

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Effect of paste content on the properties of high-strength concrete pavements
Authors: Smit M , Kearsley E
Published: January 2016

Ultra-thin continuously reinforced concrete pavement (UTCRCP) is an innovative pavement type that has the potential to fulfil South Africa's pavement repair strategy requirements. Premature failure in UTCRCP is linked to the formation of cracks that allow water ingress into supporting layers. Environmental conditions, as well as concrete properties, determine the concrete cracking tendency. Concrete properties are a function of the mixture proportions, and unlike environmental conditions, mixture proportions are controllable. The effect of mixture proportions on the properties of high-strength concrete (HSC) used in UTCRCP should be investigated. The objective of this research was to study the influence of paste content on the properties of HSC used in UTCRCP. Two sets of concrete were tested. The paste content of the first set was varied from 23% to 37% by mass, using multivariable analysis in conjunction with superplasticiser (SP) dosage. The paste content of the second set was varied from 25% to 60% by mass, only varying SP dosage to control the workability. The multivariable analysis revealed that, within the parameter range tested, paste content influenced early-age properties, but not long-term properties. Through variation of the paste content over a wider range during the second set it was found that paste content does influence both the early-age and long-term properties of HSC. From the results it could be seen that increasing the paste content of HSC generally has a detrimental effect. The paste content of HSC used in UTCRCP should be minimised, while maintaining a reasonable workability.
Pain: the voiceless scream in every haemophilia patient’s life
Authors: Rambod Masoume , Sharif Farkhondeh , Molazem Zahra , Khair Kate
Published: January 2016

Pain is a major problem in haemophilia patients’ lives. The perspective of pain in such patients is unique and may be different from other chronic illnesses. This qualitative hermeneutic phenomenological study aims to describe and interpret pain experience of haemophilia patients. Participants were selected from a haemophilia clinic affiliated with Shiraz University of Medical Sciences, Shiraz, Iran. Taking the main theme, “pain: the voiceless scream in every moment of haemophilia life”, with two subthemes, “a life full of pain” and “describing complex pain quality”, data was collected using semi-structured in-depth interviews and field notes, and thematic analysis conducted using van Manen’s methodological framework for reflective hermeneutic interpretation. The findings indicated that pain always accompanied the lives of haemophilia patients. Participants experienced acute intense pains, accompanied by bleeding, which were described as “terrible”, “severe”, “intolerable” and “unbelievable”. As joints became damaged over time, participants experienced persistent pain that was “continuous” and “constant”. Participants also coped with ever-present pain in immobile joints, described as “intense”, “annoying” and “intolerable”. This qualitative study shows that pain is present throughout haemophilia patients’ lives and that they experience different kinds of pain, demonstrated through various descriptions. By understanding the experience of pain from the perspective of haemophilia patients, nurses and healthcare workers can provide high-quality care focused on their unique needs.
Lessons from a neonate with unusual bleeding
Authors: Fosbury Emma , Blumber Raoul , Liesner Ri , Sibson Keith
Published: January 2016

Healthy, term neonates rarely encounter problems with bleeding, despite physiological differences in their levels of clotting factors, reflected in prolongation of the prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT). Their risk of bleeding, however, is significantly increased by the presence of a severe congenital bleeding disorder. Establishing such a diagnosis can present a particular challenge, given the rarity of these conditions and the difficulty in performing and interpreting laboratory assays in this age group. However, a delay in diagnosis and implementation of appropriate treatment can result in catastrophic sequelae. Therefore, the presentation of a healthy child at birth, whose condition rapidly deteriorates as a result of bleeding, should prompt the urgent investigation of a congenital haemostatic defect and involvement of expert haematological advice. We describe a very unusual presentation of a severe bleeding disorder in the first few days of life to highlight these issues.
The SIPPET study: what impact will it have on haemophilia care?
Authors: Hermans Cedric
Published: January 2016

The long-awaited results of the SIPPET (Survey of Inhibitors in Plasma-Products Exposed Toddlers) study were recently presented during a plenary session at the American Society of Hematology (ASH) conference in December 2015.
O padrão discursivo barretiano da obra Clara dos Anjos e a possibilidade dessa releitura contemporânea
Authors: Silva Adriana Reis
Published: January 2016

O presente estudo objetiva mostrar o padrão discursivo racial na produção da obra Clara dos Anjos (1922) de Lima Barreto em contraposição a essa releitura a telenovela Fera ferida (1993), de Aguinaldo Silva, Ricardo Linhares e Ana Maria Moretzsohn. Para constituir o aporte teórico estabelecido nesse trabalho, utilizamos a noção de formação discursiva segundo Michel Pêcheux (1997), buscando apreender, como a macroesturação enunciativa dos objetos Clara dos Anjos e Fera ferida se articulam através da perspectiva do dizer racial brasileiro. Parece-nos, que nesse sentido a filiação discursiva dos autores têm a capacidade de reproduzir a veleidade racial brasileira, legitimando o mito da democracia racial e o posicionamento imposto pela classe dirigente, que preza o domínio de vida capitalista. Contudo, a obra de Barreto ressignifica a óptica racial por meio da criação de “uma literatura social politicamente militante, voltada para a urgência do cotidiano em mudança e ao mesmo tempo inspirada na redenção do homem e na defesa do trabalhador oprimido pelas distorções sociais”. (PRADO, 1980, p. 13). De forma divergente, a narrativa Fera ferida mostrará, em sua trama, a desconstrução dos discursos produzidos sobre o negro, perspectiva que distorce a racialidade e, consequentemente, demanda uma nova ordem, como a criação de leis que se interpõem de forma a rever a questão racial.This study aims to show the racial pattern in the discursive production of Clara dos Anjos (1922), work of Lima Barreto in contrast to that rereading the soap opera Fera Ferida (1993), written by Aguinaldo Silva, Ricardo Linhares and Ana Maria Moretzsohn. Constituting the theoretical framework established in this work, we use the notion of discursive formation according to Michel Pêcheux (1997), seeking to understand, as the macrostructure enunciation of objects Clara dos Anjos and Fera Ferida articulate through the perspective of the Brazilian racial say. It seems to me that, in that sense the discursive affiliation of authors has the ability to play the Brazilian racial whim, legitimizing myth of racial democracy and the position imposed by the ruling class, which values the capitalist life domain. However, the work of Barreto resignifies racial optical through the creation of “a politically militant social literature, focused on the urgency of change in everyday and at the same time inspired by the redemption of man and the defense of the oppressed worker by social distortions.” (PRADO, 1980, p. 13). In different ways, the Fera Ferida narrative shows in its plot, the deconstruction of discourses produced on black, perspective that distorts raciality and therefore demand a new order, such as the creation of laws that stand in order to review the racial issue.
Treatment of Corneal Astigmatism at the Time of Cataract Surgery, What Can Be Promised
Authors: Beiko George ,   Assistant Clinical Professor, Department of Ophthalmology, McMaster University, Ontario, Canada
Published: January 2016

The treatment of corneal astigmatism at the time of cataract surgery is commonplace. Corneal incisional surgery and toric intraocular lenses (IOLs) are routinely utilised; the role of each modality is understood and defined. Although technological advances have been made in the assessment of the cornea and in the execution of the treatment options, recent innovations in toric IOL designs may be more significant for the comprehensive ophthalmologist.