bluuebunny/crossref_metadata_2025 huggingface dataset:
Presynaptic Suppression of Dorsal Horn Inhibitory Transmission by μ-Opioid Receptors
Authors: Kerchner Geoffrey A. , Zhuo Min
Published: December 2017

Opioids modify sensory experience at many levels in the CNS. The mechanisms of this action, including the ways opioid receptors affect synaptic transmission, are not yet fully understood. Here we show that the selective activation of μ-opioid receptors suppressed inhibitory transmission between spinal cord dorsal horn neurons in vitro. μ-Opioid receptor activation reduced evoked inhibitory postsynaptic current (eIPSC) amplitude by acting presynaptically, because it altered the paired-pulse ratio, did not affect GABA-evoked currents, and decreased miniature IPSC (mIPSC) frequency. The mechanism of this effect was independent both of presynaptic Ca2+ entry and of the pathway linking presynaptic kainate (KA) receptors to suppression of inhibitory transmission in the same cells. These data identify μ-opioid receptors as important presynaptic modulators of dorsal horn inhibitory transmission.
Behavior of Junction Channels Between Rat Glomus Cells During Normoxia and Hypoxia
Authors: Abudara Verónica , Jiang R. G. , Eyzaguirre C.
Published: December 2017

The activity of gap junction channels between cultured and clustered carotid body glomus cells of the rat was studied with dual voltage clamping during normoxia (Po 2 300 Torr) and hypoxia induced by sodium dithionite (Na2S2O4) or 100% N2. Na2S2O4reduced the saline Po 2 to ∼10 Torr, whereas 100% N2 reduced ambient O2 to ∼60 Torr. The following observations were made. 1) In normoxia, the intercellular macroconductance ( G j = 3.0 ± 1.01 ns, mean ± SE) was changed unevenly (increased and decreased) under hypoxic conditions by either agent, although N2 produced the largest changes. 2) The intercellular microconductances of the channels ( g j = 104.44 ± 10.16 pS under normoxic conditions) significantly decreased in 100% N2 but showed depressions and enhancements in Na2S2O4. 3) The conductance of single-junction channels (SChs), calculated as g j variance/mean g j, yielded a mean of ∼17.6 pS. Larger values were obtained with manual measurements of the data (∼34 pS). Hypoxic hypoxia (induced by 100% N2) significantly depressed the conductance of SChs when calculated from digitized records or from manual measurements. Hypoxia induced by Na2S2O4did not significantly change junctional conductance. 4) The number of intercellular channels, calculated as g j/SCh g j, had a mean of ∼452 (range 1 to 2,471). During N2-induced hypoxia, this number significantly decreased to ∼84 but remained unchanged during Na2S2O4hypoxia. 5) The mean open time of junction channels varied from 4 to 30 ms in different experiments, having an overall mean of μ = 11.33 ± 0.33 ms. This value was significantly reduced by 100% N2 but was not changed by Na2S2O4. 6) Intracellular calcium ([Ca2+]i), 46.2 ± 4.84 nM under normoxia, significantly increased to 77.32 ± 11.27 nM with Na2S2O4and to 66.39 ± 11.64 nM with 100% N2. It is concluded that 100% N2 uncouples glomus cells by significantly reducing intercellular macro- and microconductances. Hypoxia induced by Na2S2O4had variable effects. The coupling effects of hypoxia may depend on, or be aided by, increases in [Ca2+]i and/or intracellular pH changes. However, secreted transmitters and ATP plus the effects of hypoxia on second messengers and other cytoplasmic components may also play an important role in this phenomenon.
Functional Properties of Single Motor Units in the Inferior Head of Human Lateral Pterygoid Muscle: Task Firing Rates
Authors: Phanachet I. , Whittle T. , Wanigaratne K. , Murray G. M.
Published: December 2017

The precise function of the inferior head of the human lateral pterygoid muscle (IHLP) is unclear. The aim of this study was to clarify the normal function of the IHLP. The hypothesis was that an important function of the IHLP is the generation and fine control of horizontal (i.e., anteroposterior and mediolateral) jaw movements. The activities of 50 single motor units (SMUs) were recorded from IHLP (14 subjects) during two- or three-step contralateral movement ( n = 36) and/or protrusion ( n = 33). Most recording sites were identified by computer tomography. There was a statistically significant overall increase in firing rate as the magnitude of jaw displacement increased between the holding phases (range of increments: 0.3–1.6 mm). The firing rates during the dynamic phases for each unit were significantly greater than those during the previous holding phases but less than those during the subsequent holding phases. For the contralateral step task at the intermediate rate, the cross-correlation coefficients between jaw displacement in the mediolateral axis and the mean firing rate of each unit ranged from r = 0.29 to 0.77; mean ± SD; r = 0.49 ± 0.13 (protrusive step task: r = 0.12–0.74, r = 0.44 ± 0.14 for correlation with anterior–posterior axis). The correlation coefficients at the fast rate during the contralateral step task and the protrusive step task were significantly higher than those at the slow rate. The firing rate change of the SMUs per unit displacement between holding phases was significantly greater for the lower-threshold than for the higher-threshold units during contralateral movement and protrusion. After dividing IHLP into four regions, the SMUs recorded in the superior part exhibited significantly greater mean firing rate changes per unit displacement during protrusion than for the SMUs recorded in the inferior part. Significantly fewer units were related to the protrusive task in the superior–medial part. These data support previously proposed notions of functional heterogeneity within IHLP. The present findings provide further evidence for an involvement of the IHLP in the generation and fine control of horizontal jaw movements.
Extrusion of Intracellular Calcium Ion After In Vitro Ischemia in the Rat Hippocampal CA1 Region
Authors: Tanaka E. , Uchikado H. , Niiyama S. , Uematsu K. , Higashi H.
Published: December 2017

Simultaneous recordings of intracellular Ca2+([Ca2+]i) signal and extracellular DC potential were obtained from the CA1 region in 1-[6-amino-2-(5-carboxy-2-oxazolyl)-5-benzofuranyloxy]-2-(2-amino-5-methylphenoxy)-ethane- N, N, N′, N′-tetraacetic acid penta-acetoxymethyl ester (Fura-2/AM)-loaded rat hippocampal slices. Superfusion with oxygen- and glucose-deprived medium (in vitro ischemia) for 5–6 min produced a rapid rise of the [Ca2+]ilevel in the stratum radiatum (rising phase of the [Ca2+]isignal), which occurred simultaneously with a rapid negative DC potential (rapid negative potential). When oxygen and glucose were reintroduced, the increased [Ca2+]isignal diminished rapidly (falling phase of the [Ca2+]isignal) during the generation of a slow negative DC potential (slow negative potential), which occurred within 1 min from the onset of the reintroduction. Thereafter, the [Ca2+]isignal partially and the slow negative potential completely returned to the preexposure level approximately 6 min after the reintroduction. The changes in [Ca2+]isignal during and after in vitro ischemia were very similar to the changes in the membrane potential of glial cells. The rising and falling phases of [Ca2+]isignal corresponded to the rapid depolarization and a depolarizing hump, respectively, in the repolarizing phase of glial cells. A prolonged application of in vitro ischemia or a reintroduction of either glucose or oxygen suppressed the falling phase after ischemic exposure. The application of ouabain (30 μM) generated both a rapid negative potential and a rapid elevation of [Ca2+]i, but no slow negative potential or rapid reduction in [Ca2+]iwere observed. When oxygen and glucose were reintroduced to slices in the Na+-free or ouabain- or Ni2+-containing medium, the falling phase was suppressed. The falling phase was significantly accelerated in Ca2+- and Mg2+-free with EGTA-containing medium. In contrast, the falling phase was significantly slower in the Ca2+-free with high Mg2+- and EGTA-containing medium. The falling phase of the [Ca2+]isignal after ischemic exposure is thus considered to be primarily dependent on the reactivation of Na+, K+-ATPases, while the extrusion of cytosolic Ca2+via the forward-mode operation of Na+/Ca2+exchangers in glial cells is thought to be directly involved in the rapid reduction of [Ca2+]iafter ischemic exposure.
Na+ Entry Through AMPA Receptors Results in Voltage-Gated K+ Channel Blockade in Cultured Rat Spinal Cord Motoneurons
Authors: Van Damme P. , Van den Bosch L. , Van Houtte E. , Eggermont J. , Callewaert G. , Robberecht W.
Published: December 2017

α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor currents, evoked with the agonist kainate, were studied with the gramicidin perforated-patch-clamp technique in cultured rat spinal cord motoneurons. Kainate-induced currents could be blocked by the AMPA receptor antagonist LY 300164 and displayed an apparent strong inward rectification. This inward rectification was not a genuine property of AMPA receptor currents but was a result of a concomitant decrease in outward current at potentials positive to −40.5 ± 1.3 mV. The AMPA receptor current itself was nearly linear (rectification index 0.91). The kainate-inhibited outward current had a reversal potential close to the estimated K+equilibrium potential and was blocked by 30 mM tetraethylammonium. When voltage steps were applied, it was found that kainate inhibited both the delayed rectifier K+ current KV and the transient outward K+ current, KA. The kainate-induced inhibition of K+ currents was dependent on ion flux through the AMPA receptor, because no change in the membrane conductance was noticed in the presence of LY 300164. Removing extracellular Ca2+ had no effect, whereas replacing extracellular Na+ or clamping the membrane close to the estimated Na+equilibrium potential during kainate application attenuated the inhibition of the K+ current. Sustained Na+ influx induced by application of the Na+ ionophore monensin could mimic the effect of kainate on K+ conductance. These findings demonstrate that Na+ influx through AMPA receptors results in blockade of voltage-gated K+channels.
Hippocampal Contributions to Episodic Encoding: Insights From Relational and Item-Based Learning
Authors: Davachi Lila , Wagner Anthony D.
Published: December 2017

The integrity of the hippocampus and surrounding medial-temporal cortices is critical for episodic memory, with the hippocampus being posited to support relational or configural associative learning. The present event-related functional magnetic resonance imaging (fMRI) study investigated the role of specific medial-temporal lobe structures in learning during relational and item-based processing, as well as the extent to which these structures are engaged during item-based maintenance of stimuli in working memory. fMRI indexed involvement of the hippocampus and underlying cortical regions during performance of two verbal encoding conditions, one that required item-based maintenance of word triplets in working memory and the other that entailed the formation of inter-item associations across the words in each triplet. Sixteen subjects were scanned using a rapid event-related fMRI design while they encountered the item-based and relational processing trials. To examine the correlation between fMRI signal in medial-temporal structures during learning and the subject's subsequent ability to remember the stimuli (a measure of effective memory formation), subjects were administered a yes-no recognition memory test following completion of the encoding scans. Results revealed that the hippocampus proper was engaged during both relational and item-based processing, with relational processing resulting in a greater hippocampal response. By contrast, entorhinal and parahippocampal gyri were differentially engaged during item-based processing, providing strong evidence for a functional neuroanatomic distinction between hippocampal and parahippocampal structures. Analysis of the neural correlates of subsequent memory revealed that activation in the bilateral hippocampus was reliably correlated with behavioral measures of effective memory formation only for those stimuli that were encoded in a relational manner. Taken together, these data provide evidence that the hippocampus, while engaged during item-based working memory maintenance, differentially subserves the relational binding of items into an integrated memory trace so that the experience can be later remembered.
P2X Receptors in Trigeminal Subnucleus Caudalis Modulate Central Sensitization in Trigeminal Subnucleus Oralis
Authors: Hu Bo , Chiang Chen Yu , Hu James W. , Dostrovsky Jonathan O. , Sessle Barry J.
Published: December 2017

This study investigated the role of trigeminal subnucleus caudalis (Vc) P2X receptors in the mediation of central sensitization induced in nociceptive neurons in subnucleus oralis (Vo) by mustard oil (MO) application to the tooth pulp in anesthetized rats. MO application produced a long-lasting central sensitization reflected in neuroplastic changes (i.e., increases in neuronal mechanoreceptive field size and responses to innocuous and noxious mechanical stimuli) in Vo nociceptive neurons. Twenty minutes after MO application, the intrathecal (i.t.) administration to the rostral Vc of the selective P2X1, P2X3, and P2X2/3 receptor antagonist, 2′-(or 3′-) O-trinitrophenyl-ATP (TNP-ATP), significantly and reversibly attenuated the MO-induced central sensitization for more than 15 min; saline administration had no effect. Administration to the rostral Vc of the selective P2X1, P2X3, and P2X2/3 receptor agonist, α,β-methylene ATP (α,β-meATP, i.t.) produced abrupt and significant neuroplastic changes in Vo nociceptive neurons, followed by neuronal desensitization as evidenced by the ineffectiveness of a second i.t. application of α,β-meATP and subsequent MO application to the pulp. Administration to the rostral Vc of the selective P2X1 receptor agonist β,γ-methylene ATP (β,γ-meATP, i.t.) produced no significant neuroplastic changes per se and did not affect the subsequent MO-induced neuroplastic changes in Vo nociceptive neurons. These results suggest that P2X3 and possibly also the P2X2/3 receptor subtypes in Vc may play a role in the initiation and maintenance of central sensitization in Vo nociceptive neurons induced by MO application to the pulp.
Intrinsic and Synaptic Properties of Neurons in an Avian Thalamic Nucleus During Song Learning
Authors: Luo Minmin , Perkel David J.
Published: December 2017

The anterior forebrain pathway (AFP) of the avian song system is a circuit essential for song learning but not for song production. This pathway consists of a loop serially connecting area X in the basal ganglia, the medial portion of the dorsolateral nucleus of thalamus (DLM), and the pallial lateral magnocellular nucleus of the anterior neostriatum (lMAN). The majority of DLM neurons in adult male zebra finches closely resemble mammalian thalamocortical neurons in both their intrinsic properties and the strong GABAergic inhibitory input they receive from the basal ganglia. These observations support the hypothesis that the AFP and the mammalian basal ganglia-thalamocortical pathway use similar information-processing mechanisms during sensorimotor learning. Our goal was to determine whether the cellular properties of DLM neurons are already established in juvenile birds in the sensorimotor phase of song learning when the AFP is essential. Current- and voltage-clamp recording in DLM of juvenile male zebra finches showed that juvenile DLM has two distinct cell types with intrinsic properties largely similar to those of their respective adult counterparts. Immunostaining for glutamic acid decarboxylase (GAD) in juvenile zebra finches revealed that, as in adults, most area X somata are large and strongly GAD+ and that their terminals in DLM form dense GAD+ baskets around somata. GAD immunoreactivity in DLM was depleted by lesions of area X, indicating that a strong GABAergic projection from area X to DLM is already established in juveniles. Some of the DLM neurons exhibited large, spontaneous GABAergic synaptic events. Stimulation of the afferent pathway evoked an inhibitory postsynaptic potential or current that was blocked by the GABAA receptor antagonist bicuculline methiodide. The decay of the GABAAreceptor-mediated currents was slower in juvenile neurons than in adults. In addition, the reversal potential for these currents in juveniles was significantly more depolarized both than that in adults and than the Cl− equilibrium potential; yet the reversal potential was still well below the firing threshold and thus inhibitory in the slice preparation. Our findings suggest that the signal-processing role of DLM during sensorimotor learning is generally similar to that in adulthood but that quantitative changes in synaptic transmission accompany the development of stereotyped song.
Time Course and Magnitude of Movement-Related Gating of Tactile Detection in Humans. III. Effect of Motor Tasks
Authors: Williams Stephan R. , Chapman C. Elaine
Published: December 2017

This study investigated the relative importance of central and peripheral signals for movement-related gating by comparing the time course and magnitude of movement-related decreases in tactile detection during a reference motor task, active isotonic digit 2 (D2) abduction, with that seen during three test tasks: a comparison with active isometric D2 abduction (movement vs. no movement) evaluated the contribution of peripheral reafference generated by the movement to gating; a comparison with passive D2 abduction (motor command vs. no motor command; movement generated by an external agent) allowed us to evaluate the contribution of the central motor command to tactile gating; and finally, the inclusion of an active “no apparatus,” or freehand, D2 abduction task allowed us to evaluate the potential contribution of incidental peripheral reafference generated by the position detecting apparatus to the results (apparatus vs. no apparatus). Weak electrical stimuli (2-ms pulse; intensity, 90% detected at rest) were applied to D2 at different delays before and after movement onset or electromyographic (EMG) activity onset. Significant time-dependent movement-related decreases in detection were obtained with all tasks. When the results obtained during the active isotonic movement task were compared with those obtained in the three test tasks, no significant differences in the functions describing detection performance over time were seen. The results obtained with the isometric D2 abduction task show that actual movement of a body part is not necessary to diminish detection of tactile stimuli in a manner similar to the decrease produced by isotonic, active movement. In the passive test task, the peak decrease in detection clearly preceded the onset of passive movement (by 38 ms) despite the lack of a motor command and, presumably, no movement-related peripheral reafference. A slightly but not significantly earlier decrease was obtained with active movement (49 ms before movement onset). Expectation of movement likely did not contribute to the results because stimulus detection during sham passive movement trials (subjects expected but did not receive a passive movement) was not different from performance at rest (no movement). The results obtained with passive movement are best explained by invoking backward masking of the test stimuli by movement-related reafference and demonstrate that movement-related reafference is sufficient to produce decreases in detection with a time course and amplitude not significantly different from that produced by active movement.
Peripheral Inflammation Increases the Functional Coherency of Spinal Responses to Tactile but not Nociceptive Stimulation
Authors: Galhardo Vasco , Apkarian A. Vania , Lima Deolinda
Published: December 2017

Reorganization of central networks and plasticity of neuronal representations have been implicated in recent years in the dynamic expression of somatosensory responses. The functional properties of spinal cells were shown to change in the scale of minutes after peripheral high-intensity stimulations and to undergo profound alterations in their responses in experimental models of chronic pain. These observations, however, are restricted to recordings from individual cells, and no information exists on how these changes may be reflected on the activity of somatosensory neuronal networks involved in pain processing. To understand how spinal cord networks may be altered after the onset of hyperalgesia, we extracellularly recorded from groups of five to nine neighboring neurons in the hindlimb representation area of the dorsal horn. The multineuronal activity evoked by cutaneous innocuous and noxious stimulation was compared before and for 3 h after the subcutaneous injection of diluted formalin. Formalin caused immediate changes in response properties and mechanical threshold of activation for the majority of the neurons and induced the incorporation of previously unresponsive neighboring neurons to the functional network. Analysis of the temporal correlation within the neuronal population revealed that formalin-induced inflammation increased the functional coherence of the network to the nonnociceptive stimulation but not to the painful stimuli. This increase in the tactile acuity of populations of nociceptive neurons may be a basis for the emergence of touch-evoked pain.
Adaptation and Inhibition Underlie Responses to Time-Varying Interaural Phase Cues in a Model of Inferior Colliculus Neurons
Authors: Borisyuk Alla , Semple Malcolm N. , Rinzel John
Published: December 2017

A mathematical model was developed for exploring the sensitivity of low-frequency inferior colliculus (IC) neurons to interaural phase disparity (IPD). The formulation involves a firing-rate-type model that does not include spikes per se. The model IC neuron receives IPD-tuned excitatory and inhibitory inputs (viewed as the output of a collection of cells in the medial superior olive). The model cell possesses cellular properties of firing rate adaptation and postinhibitory rebound (PIR). The descriptions of these mechanisms are biophysically reasonable, but only semi-quantitative. We seek to explain within a minimal model the experimentally observed mismatch between responses to IPD stimuli delivered dynamically and those delivered statically ( McAlpine et al. 2000 ; Spitzer and Semple 1993 ). The model reproduces many features of the responses to static IPD presentations, binaural beat, and partial range sweep stimuli. These features include differences in responses to a stimulus presented in static or dynamic context: sharper tuning and phase shifts in response to binaural beats, and hysteresis and “rise-from-nowhere” in response to partial range sweeps. Our results suggest that dynamic response features are due to the structure of inputs and the presence of firing rate adaptation and PIR mechanism in IC cells, but do not depend on a specific biophysical mechanism. We demonstrate how the model's various components contribute to shaping the observed phenomena. For example, adaptation, PIR, and transmission delay shape phase advances and delays in responses to binaural beats, adaptation and PIR shape hysteresis in different ranges of IPD, and tuned inhibition underlies asymmetry in dynamic tuning properties. We also suggest experiments to test our modeling predictions: in vitro simulation of the binaural beat (phase advance at low beat frequencies, its dependence on firing rate), in vivo partial range sweep experiments (dependence of the hysteresis curve on parameters), and inhibition blocking experiments (to study inhibitory tuning properties by observation of phase shifts).
No on-off Maps in Supragranular Layers of Ferret Visual Cortex
Authors: Chapman Barbara , Gödecke Imke
Published: December 2017

Primary visual cortex contains functional maps of a number of stimulus properties including ocular dominance, orientation, direction, color, and spatial frequency. These maps must be organized with respect to each other and to a single continuous retinotopic map of visual space such that each stimulus parameter is represented at each point in space. In the ferret, geniculo-cortical inputs to cortical layer IV are segregated into on- andoff-center patches, suggesting the possibility that there might be an additional cortical map in this species. We have used optical imaging of intrinsic signals to search for on-offmaps in ferret visual cortical cells and have found none. This suggests that the high degree of on-off segregation seen subcortically in the ferret may play a role in the development of visual cortical receptive fields rather than in adult cortical function.
Autotaxin-Lysophosphatidic Acid: From Inflammation to Cancer Development
Authors: Valdés-Rives Silvia Anahi , González-Arenas Aliesha
Published: December 2017

Lysophosphatidic acid (LPA) is a ubiquitous lysophospholipid and one of the main membrane-derived lipid signaling molecules. LPA acts as an autocrine/paracrine messenger through at least six G protein-coupled receptors (GPCRs), known as LPA1–6, to induce various cellular processes including wound healing, differentiation, proliferation, migration, and survival. LPA receptors and autotaxin (ATX), a secreted phosphodiesterase that produces this phospholipid, are overexpressed in many cancers and impact several features of the disease, including cancer-related inflammation, development, and progression. Many ongoing studies aim to understand ATX-LPA axis signaling in cancer and its potential as a therapeutic target. In this review, we discuss the evidence linking LPA signaling to cancer-related inflammation and its impact on cancer progression.
Different Phenotypes of Mild Nonproliferative Diabetic Retinopathy with Different Risks for Development of Macular Edema (C-TRACER Study)
Authors: Ribeiro Luísa , Pappuru Rajeev , Lobo Conceição , Alves Dalila , Cunha-Vaz José
Published: December 2017

Purpose: To evaluate diabetic retinopathy (DR) progression in patients with diabetes mellitus type 2 in 2 populations of different ethnicity. Methods: A prospective observational study was designed to follow eyes/patients with mild nonproliferative DR, for 2 years or until the development of central-involved macular edema (CIME), in 2 centers from different regions of the world. A total of 205 eyes/patients fulfilled the inclusion/exclusion criteria and were included in this study. Ophthalmological examinations, fundus photography with RetmarkerDR analysis, and optical coherence tomography were performed at baseline and at 6, 12 and 24 months. Results: Of the 158 eyes/patients that completed this study, 24 eyes developed CIME and 134 eyes were present at the last study visit. Eighty-eight eyes (56.4%) were classified as phenotype A, 49 (31.4%) as phenotype B, and 19 (12.2%) as phenotype C. Phenotype A is associated with a very low risk for development of CIME in comparison with phenotypes B and C. The OR for development of CIME was 19.0 for phenotype B and 25.1 for phenotype C. Conclusion: Eyes in the initial stages of DR show different phenotypes with different risks of progression to ME. The phenotypes associated with increased risks of progression show different distributions in patients of different ethnicities.
Cognitive Functioning in Formerly Opioid-Dependent Adults after At Least 1 Year of Abstinence: A Naturalistic Study
Authors: Schmidt Peggy , Haberthür Annina , Soyka Michael
Published: December 2017

This study is an evaluation of cognitive functioning in formerly opioid-dependent adults after at least 1 year of abstinence. Participants (45 formerly opioid-dependent patients, referred to as abstainers, and 45 matched healthy controls) completed a structured screening and subsequent cognitive test battery covering intelligence, learning and memory, attention, and executive functions. Many cognitive functions were comparable between long-term abstainers and healthy controls, and we found few relevant differences. Long-term abstainers seem to have subtle deficits in recognition performance. Based on our and earlier findings, opioid maintenance treatment may be seen as relatively safe with respect to cognitive dysfunction and cognitive functioning is of great relevance for the rehabilitation and daily functioning of substance-dependent people.
Experimental Inhibition of Periostin Attenuates Kidney Fibrosis
Authors: Hwang Jin Ho , Yang Seung Hee , Kim Yong Chul , Kim Jin Hyuk , An Jung Nam , Moon Kyung Chul , Oh Yun Kyu , Park Jae Yoon , Kim Dong Ki , Kim Yon Su , Lim Chun Soo , Lee Jung Pyo
Published: December 2017

Background: Periostin is responsible for tissue regeneration, fibrosis, and wound healing via its interaction with integrin. Recently, the role of periostin has been shown to contribute to fibrosis in chronic kidney disease. We investigated the role of periostin and the effect of periostin blockade in renal fibrogenesis. Methods: We investigated the function of periostin in vivo in wild-type and periostin-null mice (Postn-KO) in a unilateral ureteral obstruction (UUO) model. For the in vitro experiments, primary cultured inner medullary collecting duct cells from the wild-type and Postn-KO mice were used. Results: Periostin expression was strongly induced by UUO in the wild-type mice. UUO induced renal fibrosis and morphological changes in the obstructed kidney of wild-type mice, whereas global knockout of periostin reduced fibrosis induced by UUO and improved kidney structure. Fibrosis- and inflammation-related mRNA were significantly induced in the wild-type mice and were decreased in the Postn-KO mice. Additionally, α-smooth muscle actin expression was increased following the administration of recombinant periostin in vitro. The effect of periostin blockade was examined using 2 methods. The integrin blockade peptide decreased fibrosis-related gene expression in in vitro experiments. Anti-periostin polyclonal antibody attenuated renal fibrosis induced by UUO through changes in transforming growth factor-β signaling and the inflammatory and apoptotic pathways. Conclusion: Periostin is a marker of renal fibrosis and may augment the progression of fibrogenesis as an extracellular matrix protein. Periostin blockade effectively attenuated renal fibrogenesis. Thus, periostin inhibition may be a therapeutic strategy for the amelioration of renal disease progression.
A new species of Elachistocleis (Anura: Microhylidae) from the Brazilian Pantanal
Authors: Piva Alessandher , Caramaschi Ulisses , Albuquerque Nelson Rufino de
Published: December 2017

A new species of Elachistocleis from the Brazilian Pantanal is described. The new species differs from all other Elachistocleis in having the following combination of characters: medium to large-sized species (26.9–40.3 mm); head length about 89% of head width; post-commissural gland poorly developed; dorsum in preservative (EtOH 70%) slightly rough, grayish, with minute, scattered white dots and a large, elongated dark gray spot on the mid-dorsum and posterior part of head; venter gray or brown with white spots separating dorsal and ventral regions; a single vocal sac dark gray; large, irregular, light cream spot on humerus; large, irregular light cream spots on groin; light cream, irregular stripe on posterior surfaces of thighs; and irregular, light cream spots on the proximal internal surface of each shank. This new species increases the number of Oval frogs for the state of Mato Grosso do Sul to four and demonstrates the value of the single protected area in Corumbá for biodiversity conservation. Continuing field investigations in the Maciço do Urucum are necessary to determine the diversity of the herpetofauna in that region.
Percurso da obra poética de Rui Knopfli e Manuel Alegre: uma escrita de si
Authors: Lima Kelly Mendes
Published: December 2017

O artigo pretende apresentar uma breve análise sobre o percurso poético da obra do moçambicano Rui Knopfli (1932-1997) e da do português Manuel Alegre (1936-) em correlação com experiências públicas, de ordem sócio-histórico-política, em particular o exílio, daqueles sujeitos autores. Para tanto, aborda os conceitos de escrita de si (M. Foucault) e de literatura viva (José Régio e Emerson da Cruz Inácio), aponta os (des)caminhos daquelas produções literárias e, então, para melhor estudá-los, associa eventos e discussões quanto a deslocamentos geográficos (exílios e 'desexílios', a partir de E. Said e M. Benedetti) e subjetivos ('insílios', com Paul Ilie e Miriam Lidia Volpe).
PAR4 (Protease-Activated Receptor 4) Antagonism With BMS-986120 Inhibits Human Ex Vivo Thrombus Formation
Authors: Wilson Simon J. , Ismat Fraz A. , Wang Zhaoqing , Cerra Michael , Narayan Hafid , Raftis Jennifer , Gray Timothy J. , Connell Shea , Garonzik Samira , Ma Xuewen , Yang Jing , Newby David E.
Published: December 2017

Objective—

BMS-986120 is a novel first-in-class oral PAR4 (protease-activated receptor 4) antagonist with potent and selective antiplatelet effects. We sought to determine for the first time, the effect of BMS-986120 on human ex vivo thrombus formation.

Approach and Results—

Forty healthy volunteers completed a phase 1 parallel-group PROBE trial (Prospective Randomized Open-Label Blinded End Point). Ex vivo platelet activation, platelet aggregation, and thrombus formation were measured at 0, 2, and 24 hours after (1) oral BMS-986120 (60 mg) or (2) oral aspirin (600 mg) followed at 18 hours with oral aspirin (600 mg) and oral clopidogrel (600 mg). BMS-986120 demonstrated highly selective and reversible inhibition of PAR4 agonist peptide (100 μM)-stimulated P-selectin expression, platelet-monocyte aggregates, and platelet aggregation (
P
<0.001 for all). Compared with pretreatment, total thrombus area (μm
2
/mm) at high shear was reduced by 29.2% (95% confidence interval, 18.3%–38.7%;
P
<0.001) at 2 hours and by 21.4% (9.3%–32.0%;
P
=0.002) at 24 hours. Reductions in thrombus formation were driven by a decrease in platelet-rich thrombus deposition: 34.8% (19.3%–47.3%;
P
<0.001) at 2 hours and 23.3% (5.1%–38.0%;
P
=0.016) at 24 hours. In contrast to aspirin alone, or in combination with clopidogrel, BMS-986120 had no effect on thrombus formation at low shear (
P
=nonsignificant). BMS-986120 administration was not associated with an increase in coagulation times or serious adverse events.

Conclusions—

BMS-986120 is a highly selective and reversible oral PAR4 antagonist that substantially reduces platelet-rich thrombus formation under conditions of high shear stress. Our results suggest PAR4 antagonism has major potential as a therapeutic antiplatelet strategy.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT02439190.
Infarct Fibroblasts Do Not Derive From Bone Marrow Lineages
Authors: Moore-Morris Thomas , Cattaneo Paola , Guimarães-Camboa Nuno , Bogomolovas Julius , Cedenilla Marta , Banerjee Indroneal , Ricote Mercedes , Kisseleva Tatiana , Zhang Lunfeng , Gu Yusu , Dalton Nancy D. , Peterson Kirk L. , Chen Ju , Pucéat Michel , Evans Sylvia M.
Published: December 2017

Rationale:

Myocardial infarction is a major cause of adult mortality worldwide. The origin(s) of cardiac fibroblasts that constitute the postinfarct scar remain controversial, in particular the potential contribution of bone marrow lineages to activated fibroblasts within the scar.

Objective:

The aim of this study was to establish the origin(s) of infarct fibroblasts using lineage tracing and bone marrow transplants and a robust marker for cardiac fibroblasts, the Collagen1a1-green fluorescent protein reporter.

Methods and Results:

Using genetic lineage tracing or bone marrow transplant, we found no evidence for collagen-producing fibroblasts derived from hematopoietic or bone marrow lineages in hearts subjected to permanent left anterior descending coronary artery ligation. In fact, fibroblasts within the infarcted area were largely of epicardial origin. Intriguingly, collagen-producing fibrocytes from hematopoietic lineages were observed attached to the epicardial surface of infarcted and sham-operated hearts in which a suture was placed around the left anterior descending coronary artery.

Conclusions:

In this controversial field, our study demonstrated that the vast majority of infarct fibroblasts were of epicardial origin and not derived from bone marrow lineages, endothelial-to-mesenchymal transition, or blood. We also noted the presence of collagen-producing fibrocytes on the epicardial surface that resulted at least in part from the surgical procedure.
Prodromus of a fern flora for Bolivia. XXIII. Saccolomataceae
Authors: KESSLER MICHAEL , SMITH ALAN R.
Published: December 2017

We provide a synopsis to the monogeneric fern family Saccolomataceae in Bolivia, comprising three widespread species.
Prodromus of a fern flora for Bolivia. XXIV. Lonchitidaceae
Authors: SMITH ALAN R. , KESSLER MICHAEL
Published: December 2017

We provide a synopsis to the Lonchitidaceae in Bolivia, a family comprising a single genus and species in the country and in the Neotropics. The sole species, Lonchitis hirsuta, is widespread and very similar to the only other species in the genus, L. occidentalis, in continental Africa and Madagascar.
AUTOAVALIAÇÃO DA CONDIÇÃO DE SAÚDE DA POPULAÇÃO BAIANA
Authors: Godoy Figueiredo Ana Claudia Morais , Camurugi Macedo Maria Luiza , Ferreira Cunha Daniel , Santana dos Santos Dulcineia , Evans da Silva Cabral Nidiane , Suzart Gomes-Filho Isaac , Tuy Batista Josicélia Estrela , Santana Orrico Géssica , Carvalho Lima Porto Edla , Freitas Coelho Julita Maria , Borges Silva Roberta , Seixas da Cruz Simone
Published: December 2017

Objetivo: Descrever a autoavaliação da condição de saúde da população baiana, de acordo com alguns fatores sociodemográficos. Método: Estudo de caráter transversal, cujo banco de dados utilizado foi da Pesquisa Nacional de Saúde (PNS). Foram levantados dados de 6153 pessoas, de ambos os sexos, com faixa etária acima de 18 anos, residentes na Bahia. As variáveis selecionadas foram sexo, raça/cor, estado civil, plano de saúde, diagnóstico de doença crônica, presença de depressão nas últimas semanas, nível de instrução, faixa etária e condição de saúde. Aplicou-se o teste qui-quadrado na análise dos dados, por meio do pacote estatístico Stata 15. Resultados: Definiram seu estado de saúde como bom: 56,88% dos homens, 68,87% dos indivíduos com faixa etária entre 18 e 29 anos, união estável/livre (56,24%), com plano de saúde (58,27%), ensino médio incompleto (73,66%). Em contrapartida, a maior parte das pessoas deprimidas a mais de uma semana (59,44%) e aquelas com doenças crônicas (54,48%) classificaram seu estado de saúde como regular. Conclusão: A maioria das pessoas relatou seu estado de saúde como bom. Destaca-se que essa definição foi mais frequente em pessoas do sexo masculino, jovens, com companheiro, que possuem plano de saúde e maior escolaridade.
Análise da situação de saúde e autopercepção: contribuições para a gestão dos serviços de saúde
Authors: Passos-Soares Johelle de Santana , Coelho Thereza Christina Bahia
Published: December 2017

O número 3 do volume 7 da RSC da UEFS envolve um conjunto de trabalhos desenvolvidos com uso de dados secundários e de experiências que empregaram o georreferenciamento, no intuito de investigar o comportamento de importantes problemas de saúde que ainda persistem no nosso cenário brasileiro como hepatites, doença falciforme, dengue e hipertensão. O estudo dos perfis de saúde expressa as diferentes condições de vida e trabalho, enquanto a aplicabilidade de estudos ecológicos, com uso da análise temporal e espacial dos diversos agravos à saúde, possibilita avaliar a equidade segundo variáveis demográficas e socioeconômicas.
Afrontar el desgaste: cuidado y mecanismos paliativos de la fatiga por compasión
Authors: Campos-Vidal José Francisco , Cardona-Cardona Josefa , Cuartero-Castañer María Elena
Published: December 2017

El concepto de Fatiga por Compasión (Compassion Fatigue) o Desgaste por Empatía es común en la literatura científica de Trabajo Social internacional, aunque sorprendentemente inexistente en la literatura española. Puede definirse la fatiga por compasión como estado de agotamiento y disfunción biológica, psicológica y relacional, resultado de la exposición inmediata o prolongada al estrés por compasión y como el resultado final del proceso progresivo y acumulativo consecuencia del contacto prolongado, continuado e intenso con clientes o pacientes, el uso de uno mismo y la exposición al estrés.El mantenimiento del desgaste puede derivar en cuadros severos típicos de traumatización secundaria o en el inicio del Síndrome del Profesional Quemado (Burnout). En todo caso, si un profesional del trabajo social experimenta dicho fenómeno, su capacidad para empatizar, conectar y ayudar a sus clientes se ve gravemente disminuida. Paradójicamente, la fatiga por compasión es por una parte, necesaria e inevitable si se desarrolla una buena práctica; por otra, peligrosa e inhabilitante si no se compensa mediante otros mecanismos.La fatiga por compasión no se puede prevenirse pero puede y debe paliarse de forma consciente. Incrementar la capacidad de reconocer y minimizar el impacto del desgaste es una responsabilidad del profesional y de la organización en la cual trabaja. Por último, el trabajo plantea el qué hacer ante este fenómeno y de qué manera cuidarse personal, profesional e institucionalmente.
El profesor universitario: integración entre lo personal y lo profesional
Authors: Bermúdez-Aponte José Javier , Laspalas Pérez Francisco Javier
Published: December 2017

En la primera parte de este artículo se explica cómo afectan a la labor docente ciertos cambios sociales y culturales, como son el surgimiento de la sociedad del conocimiento, la orientación hacia el mercado por parte de las universidades, las exigencias y presiones a los profesores para publicar, la pérdida del sentido ético en la actividad académica y la disparidad de tareas que hoy se le asignan al profesor universitario. A raíz de lo anterior, se propone un modelo comprensivo de docente universitario compuesto por dos ejes o vertientes –lo personal y lo profesional–, que incorpora y sintetiza diferentes aportaciones sobre este tema. Finalmente, se defiende la necesidad de entender la labor docente universitaria como una vocación, en el sentido más hondo de la palabra; una vocación lleva consigo la inclinación a perseguir un fin: la formación y educación de los estudiantes que tenemos encomendados.
Efectos de la comunicación dialógica en la mejora de la composición escrita en estudiantes de primaria
Authors: Gutiérrez-Fresneda Raúl , Díez-Mediavilla Antonio
Published: December 2017

La escritura es una herramienta imprescindible para el éxito académico que requiere de unas habilidades y estrategias de gran complejidad que no siempre se enseñan en el ámbito escolar. El propósito de este trabajo fue analizar si, mediante un programa de enseñanza de las estrategias de producción escrita implementado a través de la comunicación dialógica en grupos interactivos, se adquiere una mejor composición escrita. Se empleó un diseño cuasiexperimental de comparación entre grupos con medidas pretest y postest. En el estudio participaron 409 estudiantes con edades comprendidas entre los 8 y los 9 años. Los resultados apoyan el valor potencial del programa y sugieren el desarrollo de modelos de enseñanza que integren prácticas de comunicación dialógica, por lo que se recomienda el diseño de programas orientados al desarrollo de las estrategias de composición a través de grupos interactivos en cuanto que facilitan el aprendizaje de la composición escrita.
Zukunftsstadt: Forschung für klimaresiliente, sozial-ökologisch gerechte und lebenswerte Städte
Authors: Schmidt Andreas
Published: December 2017

Das Bundesministerium für Bildung und Forschung (BMBF) verstärkt mit der Fördermaßnahme Umsetzung der Leitinitiative Zukunftsstadt den Schwerpunkt der umsetzungsorientierten Stadtforschung. Durch bedarfsgerechte, praxisorientierte, inter- und transdisziplinäre
Forschung soll die Fördermaßnahme Impulse für die nachhaltige Entwicklung auf kommunaler Ebene setzen.
Integrating Interdisciplinarity and Internationality in Sustainable Development Education
Authors: Brudermann Thomas , Holländer Robert , Pastres Roberto , Posch Alfred , Schot Paul
Published: December 2017

Growing awareness of environmental and social issues in economic development contributes to move the idea of sustainable development forward. Since 2008, the Joint International Master in Sustainable Development offers an international and interdisciplinary approach to the hotly
debated topic. It combines the strengths of the eight partner universities in Europe, Asia and Africa.
The neural events that change perception
Authors: Krug Kristine , Parker Andrew J.
Published: December 2017

Neuroscientific research has made tremendous progress towards unravelling the neuronal codes that underlie our rich sensory perception and experience. From single neurons in primates’ visual brain that predict perceptual choices to activity patterns in defined neuronal circuits, electrical activity across different levels correlates with perception. The key to how neuronal signals give rise to our visual experience lies in causal interventions directly applied to neurons and circuits, interventions that alter perception naturalistically and in predictable ways. The most powerful and reliable intervention method in primates remains invasive electrical micro-stimulation, which can change selectively the appearance of visual objects defined by more than one visual cue. Such artificial signals are integrated with visually evoked stimuli and with contextual factors like reward. Scaling up these methodologies presents opportunities for vision replacement through cortical neuro-prosthetics.
Effect of Urea on the Shape and Structure of Carbon Nanotubes
Authors: Elamin M. R. , Abdulkhair Babiker Y. , Taha Kamal K.
Published: December 2017

Coiled multiwall carbon nanotubes (MWCNTs) were prepared on Fe, Co, and Ni metal oxides supported on α-Al2O3 using urea as fuel and catalyst surface modifying agent by catalytic chemical vapour deposition (CCVD). The shape of the nanotubes was influenced by the addition of urea, where coiled and uncoiled tubes were obtained in the presence and absence of urea, respectively. The MWCNTs were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption analysis. The coiling/uncoiling of the nanotubes was visualized from the SEM and TEM images of the prepared specimens. The XRD data showed the characteristic peaks of the nanotubes. BET analysis of the coiled tubes revealed 85.57 m2 g−1 surface area with a pore diameter 102.2–110.8 Å. A mechanism for the nanotubes coiling is suggested.
Cystic Fibrosis as a Theme to Incorporate Team-Based Learning in Cell Biology Courses
Authors: Hurst-Kennedy Jennifer
Published: December 2017

Team-based learning (TBL) is structured, cooperative learning teaching strategy used in a variety of disciplines. TBL uses a three-step approach for delivering content to students: out-of-class preparation, readiness assurance, and application. In this article, a method for incorporating TBL into an undergraduate cell biology course using cystic fibrosis (CF) as a theme is described. Class content is divided into modules. Each module consists of (1) out-of-class video viewing and reading assignments; (2) individual and team assessments, mini-lectures, and think-pair-share activities to assess understanding of the material; and (3) in-class, group problem sets related to the molecular pathogenesis of CF. Although originally designed for an introductory undergraduate cell biology course, this curriculum can be easily adapted for upper-level undergraduate and high school students.