bluuebunny/crossref_metadata_2025 huggingface dataset:
Intrinsic and Extrinsic Modulation of a Single Central Pattern Generating Circuit
Authors: Morgan Peter T. , Perrins Ray , Lloyd Philip E. , Weiss Klaudiusz R.
Published: December 2017

Intrinsic and extrinsic neuromodulation are both thought to be responsible for the flexibility of the neural circuits (central pattern generators) that control rhythmic behaviors. Because the two forms of modulation have been studied in different circuits, it has been difficult to compare them directly. We find that the central pattern generator for biting in Aplysia is modulated both extrinsically and intrinsically. Both forms of modulation increase the frequency of motor programs and shorten the duration of the protraction phase. Extrinsic modulation is mediated by the serotonergic metacerebral cell (MCC) neurons and is mimicked by application of serotonin. Intrinsic modulation is mediated by the cerebral peptide-2 (CP-2) containing CBI-2 interneurons and is mimicked by application of CP-2. Since the effects of CBI-2 and CP-2 occlude each other, the modulatory actions of CBI-2 may be mediated by CP-2 release. Although the effects of intrinsic and extrinsic modulation are similar, the neurons that mediate them are active predominantly at different times, suggesting a specialized role for each system. Metacerebral cell (MCC) activity predominates in the preparatory (appetitive) phase and thus precedes the activation of CBI-2 and biting motor programs. Once the CBI-2s are activated and the biting motor program is initiated, MCC activity declines precipitously. Hence extrinsic modulation prefacilitates biting, whereas intrinsic modulation occurs during biting. Since biting inhibits appetitive behavior, intrinsic modulation cannot be used to prefacilitate biting in the appetitive phase. Thus the sequential use of extrinsic and intrinsic modulation may provide a means for premodulation of biting without the concomitant disruption of appetitive behaviors.
Somatostatin Modulation of Excitatory Synaptic Transmission Between Periventricular and Arcuate Hypothalamic Nuclei In Vitro
Authors: Lanneau Christophe , Peineau Stéphane , Petit Florence , Epelbaum Jacques , Gardette Robert
Published: December 2017

Hypophysiotropic somatostatin (SRIF) and growth hormone–releasing hormone (GHRH) neurons are primarily involved in the neurohormonal control of growth hormone (GH) secretion. They are located in periventricular (PEV) and arcuate (ARC) hypothalamic nuclei, respectively, but their connectivity is not well defined. To better understand the neuronal network involved in the control of GH secretion, connections from PEV to ARC neurons were reconstructed in vitro and neuronal phenotypes assessed by single-cell multiplex RT-PCR. Of 814 stimulated PEV neurons, monosynaptic responses were detected in only 45 ARC neurons. Monosynaptic excitatory currents were detected in 29 ARC neurons and inhibitory currents in 16, indicating a 2/1 ratio for excitatory versus inhibitory connections. Galanin (GAL), NPY, pro-opiomelanocortin (POMC), and SRIF mRNAs were detected in neurons from both nuclei but GHRH mRNA almost exclusively in ARC. Among the five SRIF receptors, only sst1 and sst2 were expressed, in 94% of ARC and 59% of PEV neurons, respectively. Of 128 theoritical combinations between neuropeptides and sst receptors, only 22 were represented in PEV and 25 in ARC. For PEV neurons, neuropeptide phenotypes did not influence excitatory connections. However, the occurrence of presynaptic sst receptors on GAL and SRIF PEV neurons significantly increased their probability of connection to ARC neurons. GHRH ARC neurons expressing sst2, but not sst1, receptors were always connected with PEV neurons. Physiological responses to sst1 (CH-275) or sst2 (Octreotide) agonists were always correlated with the detection of respective sst mRNAs. In conclusion, 1) SRIF-modulated excitatory transmission develops in vitro from PEV to ARC neurons, 2) ARC GHRH neurons bearing sst2 receptors appears directly controlled by fast glutamatergic transmission from PEV neurons simultaneously expressing one to four neuropeptides, 3) GHRH neurons bearing sst1 receptors lack this control, and 4) these results suggest that fast excitatory neurotransmission and neuropeptide modulation can derive from a small subset of PEV hypothalamic neurons targeted at ARC neuronal subpopulations.
G-Protein-Modulated Ca2+ Current With Slowed Activation Does Not Alter the Kinetics of Action Potential-Evoked Ca2+ Current
Authors: Artim Debra E. , Meriney Stephen D.
Published: December 2017

We have studied voltage-dependent inhibition of N-type calcium currents to investigate the effects of G-protein modulation-induced alterations in channel gating on action potential-evoked calcium current. In isolated chick ciliary ganglion neurons, GTPγS produced voltage-dependent inhibition that exhibited slowed activation kinetics and was partially relieved by a conditioning prepulse. Using step depolarizations to evoke calcium current, we measured tail current amplitudes on abrupt repolarization to estimate the time course of calcium channel activation from 1 to 30 ms. GTPγS prolonged significantly channel activation, consistent with the presence of kinetic slowing in the modulated whole cell current evoked by 100-ms steps. Since kinetic slowing is caused by an altered voltage dependence of channel activation (such that channels require stronger or longer duration depolarization to open), we asked if GTPγS-induced modulation would alter the time course of calcium channel activation during an action potential. Using an action potential waveform as a voltage command to evoke calcium current, we abruptly repolarized to −80 mV at various time points during the repolarization phase of the action potential. The resulting tail current was used to estimate the relative number of calcium channels that were open. Using action potential waveforms of either 2.2- or 6-ms duration at half-amplitude, there were no differences in the time course of calcium channel activation, or in the percent activation at any time point tested during the repolarization, when control and modulated currents were compared. It is also possible that modulated channels might open briefly and that these reluctant openings would effect the time course of action potential-evoked calcium current. However, when control and modulated currents were scaled to the same peak amplitude and superimposed, there was no difference in the kinetics of the two currents. Thus voltage-dependent inhibition did not alter the kinetics of action potential-evoked current. These results suggest that G-protein-modulated channels do not contribute significantly to calcium current evoked by a single action potential.
Cerebral-Abdominal Interganglionic Coordinating Neurons inAplysia
Authors: Xin Yuanpei , Koester John , Jing Jian , Weiss Klaudiusz R. , Kupfermann Irving
Published: December 2017

Three cerebral-abdominal interneurons (CAIs), CC2, CC3, and CC7, were identified in the cerebral ganglion C cluster. The cells send their axons to the abdominal ganglion via the pleural-abdominal connective. CC2 and CC3 are bilaterally symmetrical cells, whereas CC7 is a unilateral cell. CC3 is immunopositive for serotonin and may be the same cell (CB-1) previously described as located in the B cluster rather than the C cluster. We suggest that the full designation of CC3, be CC3(CB-1). All three cells respond to feeding-related inputs. Each CAI has a monosynaptic connection to at least one abdominal ganglion neuron involved in the control of various nonsomatic organs. The CAIs also exert widespread polysynaptic actions in the abdominal and head ganglia. The results suggest that the CAIs may act as interneurons that coordinate visceral responses mediated by the abdominal ganglion, with behaviors such as feeding and head withdrawal, that are controlled by neurons located in the head ganglia of the animal.
Synchronization in Monkey Motor Cortex During a Precision Grip Task. I. Task-Dependent Modulation in Single-Unit Synchrony
Authors: Baker S. N. , Spinks R. , Jackson A. , Lemon R. N.
Published: December 2017

Neural synchronization in the cortex, and its potential role in information coding, has attracted much recent attention. In this study, we have recorded long spike trains (mean, 33,000 spikes) simultaneously from multiple single neurons in the primary motor cortex (M1) of two conscious macaque monkeys performing a precision grip task. The task required the monkey to use its index finger and thumb to move two spring-loaded levers into a target, hold them there for 1 s, and release for a food reward. Synchrony was analyzed using a time-resolved cross-correlation method, normalized using an estimate of the instantaneous firing rate of the cell. This was shown to be more reliable than methods using trial-averaged firing rate. A total of 375 neurons was recorded from the M1 hand area; 235 were identified as pyramidal tract neurons. Synchrony was weak [mean k′ = 1.05 ± 0.04 (SD)] but widespread among pairs of M1 neurons (218/1359 pairs with above-chance synchrony), including output neurons. Synchrony usually took the form of a broad central peak [average width, 18.7 ± 8.7 (SD) ms]. There were marked changes during different phases of the task. As a population, synchrony was greatest during the steady hold period in striking contrast to the averaged cell firing rate, which was maximal when the animal was moving the levers into target. However, the modulation of synchrony during task performance showed considerable variation across individual cell pairs. Two types of synchrony were identified: oscillatory (with periodic side lobes in the cross-correlation) and nonoscillatory. Their relative contributions were quantified by filtering the cross-correlations to exclude either frequencies from 18 to 37 Hz or all higher and lower frequencies. At the peak of population synchrony during the hold period, about half (51.7% in one monkey, 56.2% in the other) of the synchronization was within this oscillatory bandwidth. This study provides strong support for assemblies of neurons being synchronized during specific phases of a complex task with potentially important consequences for both information processing within M1 and for the impact of M1 commands on target motoneurons.
The Motor Output and Behavior Produced by Rhythmogenic Sacrocaudal Networks in Spinal Cords of Neonatal Rats
Authors: Delvolvé I. , Gabbay H. , Lev-Tov A.
Published: December 2017

The characteristics of the rhythmic motor output and behavior produced by intrinsic sacrocaudal networks were studied in isolated tail-spinal cord preparations of neonatal rats. An alternating left-right rhythm could be induced in the sacral cord by stimulus trains applied to sacrocaudal afferents at various intensities. Strengthening the stimulation intensity enhanced the rhythmic efferent firing and accelerated the rhythm by ≤30%. High stimulation intensities induced tonic excitation or inhibition and thereby perturbed the rhythm. Increasing the stimulation frequency from 1 to 10 Hz decreased the cycle time of the rhythm by 36%. The rhythm was blocked during prolonged afferent stimulation but could be restored by stimulation of contralateral afferents. Sacrocaudal afferent activation produced ventroflexion accompanied by either low- or high-amplitude rhythmic abduction of the tail. The low-amplitude abductions were produced by alternating flexor bursts during long stimulus trains. The activity of abductors and extensors was substantially reduced during these trains, their recruitment lagged after that of the flexors, and their activity bursts were much shorter. It is suggested that tail extensor/abductor motoneurons were suppressed during the stimulus train by inhibitory afferent projections. The high-amplitude abductions appeared after cessation of stimulus trains. Alternating left-right activation of the tail muscles, and coactivation of the principal muscles on each side of the tail were observed during these abductions. It is suggested that flexors and extensors assist the abductors to produce the high-amplitude abductions. This suggestion is supported by the finding that tail abduction could be produced by direct unilateral stimulation of any of the principal tail muscles. The relevance of the findings described in the preceding text to the use of regional sacral circuits in generation of stereotypic motor behaviors and to future studies of rhythmogenic sacrocaudal networks is discussed.
Characteristics of Glutamate-Evoked Temporomandibular Joint Afferent Activity in the Rat
Authors: Cairns Brian E. , Sessle Barry J. , Hu James W.
Published: December 2017

Injection of glutamate into the rat temporomandibular joint (TMJ) capsule can reflexly induce a prolonged increase in the electromyographic (EMG) activity of the jaw muscles, however, the characteristics of TMJ afferents activated by glutamate have not been investigated. In the present study, we examined the effect of glutamate injection into the TMJ capsule on jaw muscle EMG activity and the extracellularly recorded activity of single trigeminal afferents that had receptive fields in the TMJ tissue and antidromically identified projections to the brain stem subnucleus caudalis (Vc) in rats of both sexes. Glutamate (0.05–1.0 M, 10 μl) injection into the TMJ capsule evoked EMG activity in a dose-related manner; however, at concentrations of 0.5 and 1.0 M, glutamate-evoked digastric muscle responses were greater in female than in male rats. In experiments where jaw muscle EMG and afferent activity were recorded simultaneously, glutamate (0.5 M, 10 μl) injection into the TMJ capsule evoked activity in the jaw muscles as well as in 27 (26 Aδ and 1 C-fiber afferent) of 34 trigeminal afferents that could be activated by blunt mechanical stimulation of the TMJ tissue. In these experiments, glutamate-evoked jaw muscle activity was significantly increased for 6 min after the glutamate injection, whereas afferent activity was significantly increased only during the first minute after the glutamate injection. The glutamate-evoked afferent activity was inversely related to conduction velocity and, in afferents with conduction velocities <10 m/s, was significantly greater in female ( n = 6) than in male ( n = 10) rats. These results suggest that glutamate excites putative nociceptive afferents within the TMJ to a greater degree in female than in male rats. This sex-related difference in afferent discharge may, in part, underlie sex-related differences in glutamate-evoked jaw muscle EMG activity.
Role of Retinal Slip in the Prediction of Target Motion During Smooth and Saccadic Pursuit
Authors: de Brouwer Sophie , Missal Marcus , Lefèvre Philippe
Published: December 2017

Visual tracking of moving targets requires the combination of smooth pursuit eye movements with catch-up saccades. In primates, catch-up saccades usually take place only during pursuit initiation because pursuit gain is close to unity. This contrasts with the lower and more variable gain of smooth pursuit in cats, where smooth eye movements are intermingled with catch-up saccades during steady-state pursuit. In this paper, we studied in detail the role of retinal slip in the prediction of target motion during smooth and saccadic pursuit in the cat. We found that the typical pattern of pursuit in the cat was a combination of smooth eye movements with saccades. During smooth pursuit initiation, there was a correlation between peak eye acceleration and target velocity. During pursuit maintenance, eye velocity oscillated at ∼3 Hz around a steady-state value. The average gain of smooth pursuit was ∼0.5. Trained cats were able to continue pursuing in the absence of a visible target, suggesting a role of the prediction of future target motion in this species. The analysis of catch-up saccades showed that the smooth-pursuit motor command is added to the saccadic command during catch-up saccades and that both position error and retinal slip are taken into account in their programming. The influence of retinal slip on catch-up saccades showed that prediction about future target motion is used in the programming of catch-up saccades. Altogether, these results suggest that pursuit systems in primates and cats are qualitatively similar, with a lower average gain in the cat and that prediction affects both saccades and smooth eye movements during pursuit.
Differential Coding of Pain Intensity in the Human Primary and Secondary Somatosensory Cortex
Authors: Timmermann Lars , Ploner Markus , Haucke Katrin , Schmitz Frank , Baltissen Rüdiger , Schnitzler Alfons
Published: December 2017

The primary (SI) and secondary (SII) somatosensory cortices have been shown to participate in human pain processing. However, in humans it is unclear how SI and SII contribute to the encoding of nociceptive stimulus intensity. Using magnetoencephalography (MEG) we recorded responses in SI and SII in eight healthy humans to four different intensities of selectively nociceptive laser stimuli delivered to the dorsum of the right hand. Subjects' pain ratings correlated highly with the applied stimulus intensity. Activation of contralateral SI and bilateral SII showed a significant positive correlation with stimulus intensity. However, the type of dependence on stimulus intensity was different for SI and SII. The relation between SI activity and stimulus intensity resembled an exponential function and matched closely the subjects' pain ratings. In contrast, SII activity showed an S-shaped function with a sharp increase in amplitude only at a stimulus intensity well above pain threshold. The activation pattern of SI suggests participation of SI in the discriminative perception of pain intensity. In contrast, the all-or-none–like activation pattern of SII points against a significant contribution of SII to the sensory-discriminative aspects of pain perception. Instead, SII may subserve recognition of the noxious nature and attention toward painful stimuli.
Wavelets of Excitability in Sensory Neurons
Authors: Hasty Jeff , Collins J. J. , Wiesenfeld Kurt , Grigg Peter
Published: December 2017

We have investigated variations in the excitability of mammalian cutaneous mechanoreceptor neurons. We focused on the phase dynamics of an action potential relative to a periodic stimulus, showing that the excitability of these sensory neurons has interesting nonstationary oscillations. Using a wavelet analysis, these oscillations were characterized through the depiction of their period as a function of time. It was determined that the induced oscillations are weakly dependent on the stimulus frequency, and that lower temperatures significantly reduce the frequency of the phase response. Our results reveal novel excitability properties in sensory neurons, and, more generally, could prove significant in the deduction of mechanistic attributes underlying the nonstationary excitability in neuronal systems. Since peripheral neurons feed information to the CNS, variable responses observed in higher regions may be generated in part at the site of sensory detection.
Differential Modulation of Respiratory Neuronal Discharge Patterns by GABAA Receptor and Apamin-Sensitive K+ Channel Antagonism
Authors: Tonkovic-Capin V. , Stucke A. G. , Stuth E. A. , Tonkovic-Capin M. , Krolo M. , Hopp F. A. , McCrimmon D. R. , Zuperku E. J.
Published: December 2017

The discharge patterns of respiratory neurons of the caudal ventral respiratory group (cVRG) appear to be subject to potent GABAergic gain modulation. Local application of the GABAA receptor antagonist bicuculline methochloride amplifies the underlying discharge frequency ( F n) patterns mediated by endogenous excitatory and inhibitory synaptic inputs. Gain modulation can also be produced by alterations in the amplitude of spike afterhyperpolarizations (AHPs) mediated by apamin-sensitive small-conductance Ca2+-activated K+ (SK) channels. Since methyl derivatives of bicuculline (BICm) also have been shown to reduce the amplitude of AHPs, in vitro, it is possible that the BICm-induced gain modulation is due to a block of SK channels. The purpose of these studies was to determine the mechanisms by which BICm produces gain modulation and to characterize the influence of SK channels in the control of respiratory neuron discharge. Six protocols were used in this in vivo study of cVRG inspiratory (I) and expiratory (E) neurons in decerebrate, paralyzed, ventilated dogs. The protocols included characterizations of the neuronal responses to 1) BICm and apamin on the same neuron, 2) BICm during maximum apamin-induced block of AHPs, 3) apamin during maximum BICm-induced gain modulatory responses, 4) the specific GABAAreceptor antagonist, (+)β-hydrastine, 5) the specific GABAA receptor agonist, muscimol, and 6) the GABA uptake inhibitor, nipecotic acid. For protocols 3, 5, and 6, only E neurons were studied. Four-barrel micropipettes were used for extracellular single neuron recording and pressure ejection of drugs. Cycle-triggered histograms were used to quantify the F n patterns and to determine the drug-induced changes in the gain (slope) and offset of the F n patterns. Compared to apamin at maximum effective dose rates, BICm produced a 2.1-fold greater increase in peak F n and a 3.1-fold greater increase in average F n. BICm and apamin produced similar increases in gain, but the offsets due to apamin were more negative. The responses to hydrastine were similar to BICm. During maximum apamin block, BICm produced an additional 112 ± 22% increase in peak F n. Conversely, apamin produced an additional 176 ± 74% increase in peak F n during the maximum BICm-induced response. Muscimol and nipecotic acid both decreased the gain and offset of the discharge patterns. Taken together, these results suggest that the gain modulatory effect of BICm is due to a reduction of GABAA-ergic shunting inhibition rather than a reduction in AHPs by block of SK channels in canine cVRG neurons.
Effects of Protein Kinase A Activation on the Responses of Primate Spinothalamic Tract Neurons to Mechanical Stimuli
Authors: Lin Qing , Wu Jing , Willis William D.
Published: December 2017

Behavioral and anatomical studies by our group have suggested that the protein kinase A (PKA) signal transduction cascade contributes to long-term changes in nociceptive processing at the spinal cord level. In this study, we have examined the effects of activation of the PKA cascade on the responses of spinothalamic tract (STT) neurons to peripheral mechanical stimuli in anesthetized and paralyzed monkeys. PKA in the spinal cord was activated by intra-spinal infusion of forskolin, an activator of adenylate cyclase, by microdialysis. There was a consistent increase in responses to mechanical pressure and pinch stimuli in all STT cells tested when forskolin was administered. Enhanced responses remained at relatively high levels when forskolin had been washed out for 30 min. However, in most STT cells tested (65%), the responses to brushing stimuli were not obviously changed when forskolin was given. Background activity was slightly increased when forskolin was administered. An inactive isomer of forskolin,d-forskolin, did not produce significant effects on cellular activity. The sensitization of STT cells to noxious mechanical stimuli produced by forskolin could be blocked by pretreatment of the spinal cord with the PKA inhibitor, N-[2-(( p-bromocinnamyl)amino)ethyl]-5-isoquinolinesulfonamine (H89). The same dose of H89 did not affect the enhanced responses to mechanical stimuli produced by activation of protein kinase G by intra-spinal infusion of 8-bromo-cGMP, indicating that the effect of forskolin was selective. The present data suggest that activation of PKA can preferentially enhance the responses of STT cells to noxious mechanical stimuli without producing an increase in responses to innocuous brushing stimuli. We speculate that the PKA signal transduction cascade may contribute more to secondary mechanical hyperalgesia than to secondary mechanical allodynia.
Role of High-Voltage Activated Potassium Currents in High-Frequency Neuronal Firing: Evidence From a Basal Metazoan
Authors: Buckingham Steven D. , Spencer Andrew N.
Published: December 2017

Certain neurons of vertebrates are specialized for high-frequency firing. Interestingly, high-frequency firing is also seen in central neurons in basal bilateral metazoans. Recently, the role of potassium currents with rightward-shifted activation curves in producing high-frequency firing has come under scrutiny. We apply intracellular recording, patch-clamp techniques, and compartmental modeling to examine the roles of rightward-shifted potassium currents in repetitive firing and shaping of action potentials in central neurons of the flatworm, Notoplana atomata ( Phylum Platyhelminthes). The kinetic properties of potassium and sodium currents were determined from patch-clamp experiments on dissociated brain cells. To predict the effects of changing the steady-state and kinetic properties of these potassium currents, these data were incorporated into a computer model of a 30-μm spherical cell with the levels of current adjusted to approximate the values recorded in voltage-clamp experiments. The model was able to support regenerative spikes at high frequencies in response to injected current. Current-clamp recordings of cultured cells and of neurons in situ also showed evidence of very-high-frequency firing. Adjusting the ratio of inactivating to non-inactivating potassium currents had little effect upon the firing pattern of the cell or its ability to fire at high frequencies, whereas the presence of the non-inactivating current was necessary for repetitive firing. Computer simulations suggested that the rightward shift in voltage sensitivity confers a raised firing threshold, while rapid channel kinetics underlie high frequency firing, and the large activation range enhances the coding range of the cell.
Chronic Electrical Stimulation of Afferents From One Eye Changes Ocular Dominance of Visual Cortical Neurons in Kittens
Authors: Ohshima Minoru , Hata Yoshio , Ichisaka Satoshi , Wakita Masumi , Fukuda Mitsuhiro , Kameyama Katsuro , Tsumoto Tadaharu
Published: December 2017

Binocular visual responsiveness of neurons in visual cortex of the cat can be changed by monocular visual deprivation in the critical period of postnatal development. It is hypothesized that afferents from each eye compete with one another for synaptic connections with cortical neurons so that less active afferents from the deprived eye fail to maintain the connections. This hypothesis predicts that an increase in inputs from one eye instead of decrease due to deprivation should also change binocular responsiveness of cortical neurons. However, the hypothesis has not successfully been tested with experimental activation of afferents from one eye. In the present study, we activated one of the optic nerves by chronic electrical stimulation of θ-burst type in behaving kittens for 2 days. After such a monocular activation, visual cortical neurons showed a significant ocular dominance shift in favor of the electrically activated eye, although neurons in the activated and nonactivated layers of the dorsal lateral geniculate nucleus had no biased visual responses. Also, we found no detectable difference between activated and nonactivated eye responses of cortical neurons in other response properties such as orientation selectivity. These results support the hypothesis that the balance between activities of both afferents is critical for formation or consolidation of each eye-specific pathway.
Minimally Invasive Repetitive UVA Irradiation along with Riboflavin Treatment Increased the Strength of Sclera Collagen Cross-Linking
Authors: Xiao Bo , Chu Yanhua , Wang Hongyan , Han Quanhong
Published: December 2017

Objective. This study aimed to investigate the efficacy of minimally invasive repetitive UVA irradiation along with riboflavin treatment on sclera collagen cross-linking in rabbits. Method. Forty-eight healthy adult New Zealand white rabbits were randomly divided into four groups: pseudosurgery group (group I), single-irradiation group (group II), duplicate-irradiation group (group III), and triplicate-irradiation group (group IV), with 12 rabbits in each group. For the single-irradiation group, a specially made LED light source was inserted through a minimally invasive conjunctival incision to gain close contact with the sclera for irradiation, and for the repetitive irradiation groups, the above experimental procedure was repeated once or twice every other week. Biomechanical parameters of the sclera including ultimate stress (σ) and 8% Young’s modulus (E) were compared among the groups. Results. In comparison with control group I, the ultimate stress of group II, group III, and group IV increased by 80.1%, 107.9%, and 182.1%, respectively, and their 8% Young’s modulus increased by 106.1%, 159.5%, and 208.5%, respectively, one day after surgery (P<0.01). Conclusion. Repetitive minimally invasive UVA irradiation with riboflavin significantly increased biomechanical strength of the sclera in the irradiated area, and biomechanical strength increased with repeated times of irradiation.
Carbonation of Water Repellent-Treated Concrete
Authors: Zhang Peng , Li Peibing , Fan Hong , Shang Huaishuai , Guo Siyao , Zhao Tiejun
Published: December 2017

Water repellent treatment has been considered an effective preventive method against water and aggressive ions penetration into concrete and consequently can improve the durability of concrete structures. In reality, many concrete structures are exposed to conditions with high risk of carbonation. In this contribution, one type of ordinary concrete had been prepared and surface impregnated by 400 g/m2silane cream and 100 g/m2and 400 g/m2silane gel. In addition, integral water repellent concrete was produced by adding 2% silane emulsion. Then, the specimens were exposed to accelerated carbonation for 7, 28, and 72 days. The effect of water repellent treatment on carbonation of concrete has been investigated. The results indicate that surface impregnation reduced carbonation depth of concrete under RH 70%, but integral water repellent concrete increased carbonation. Carbonation reaction started behind the hydrophobic layer in the surface-impregnated concrete. The coefficient of carbonation can be described better by a hyperbolic function of time. Treatment by 400 g/m2silane gel and silane cream showed better efficiency on reducing carbonation than usage of 100 g/m2. Coefficient of water capillary suction was decreased significantly by both surface impregnation and integral water repellent treatment. It is an effective method to protect concrete from water penetration into the material.
Epidemiology of Respiratory Pathogens among Elderly Nursing Home Residents with Acute Respiratory Infections in Corsica, France, 2013–2017
Authors: Masse Shirley , Capai Lisandru , Falchi Alessandra
Published: December 2017

Background. The current study aims to describe the demographical and clinical characteristics of elderly nursing home (NH) residents with acute respiratory infections (ARIs) during four winter seasons (2013/2014–2016/2017), as well as the microbiological etiology of these infections. Methods. Seventeen NHs with at least one ARI resident in Corsica, France, were included. An ARI resident was defined as a resident developing a sudden onset of any constitutional symptoms in addition to any respiratory signs. Nasopharyngeal swabs from ARI residents were screened for the presence of 21 respiratory agents, including seasonal influenza viruses. Results. Of the 107 ARI residents enrolled from NHs, 61 (57%) were positive for at least one of the 21 respiratory pathogens. Forty-one (38.3%) of the 107 ARI residents had influenza: 38 (92%) were positive for influenza A (100% A(H3N2)) and three (8%) for influenza B/Victoria. Axillary fever (≥38°C) was significantly more common among patients infected with influenza A(H3N2). Conclusion. The circulation of seasonal respiratory viruses other than influenza A(H3N2) seems to be sporadic among elderly NH residents. Investigating the circulation of respiratory viruses in nonwinter seasons seems to be important in order to understand better the dynamic of their year-round circulation in NHs.
Design of Gain Scheduling Control Using State Derivative Feedback
Authors: Llins Lázaro Ismael Hardy , Assunção Edvaldo , Teixeira Marcelo C. M. , Cardim Rodrigo , Cadalso Mario R. R. , Oliveira Diogo R. de , da Silva Emerson R. P.
Published: December 2017

In recent years, the study of systems subject to time‐varying parameters has awakened the interest of many researchers. The gain scheduling control strategy guarantees a good performance for systems of this type and also is considered as the simplest to deal with problems of this nature. Moreover, the class of systems in which the state derivative signals are easier to obtain than the state signals, such as in the control for reducing vibrations in a mechanical system, has gained an important hole in control theory. Considering those ideas, we propose sufficient conditions via LMI for designing a gain scheduling controller using state derivative feedback. The ‐stability methodology was used for improving the performance of the transitory response. Practical implementation in an active suspension system and comparison with other methods validates the efficiency of the proposed strategy.
Soft Tissue Repair with Easy-Accessible Autologous Newborn Placenta or Umbilical Cord Blood in Severe Malformations: A Primary Evaluation
Authors: Ekblad Åsa , Fossum Magdalena , Götherström Cecilia
Published: December 2017

Disrupted organogenesis leads to permanent malformations that may require surgical correction. Autologous tissue grafts may be needed in severe lack of orthotopic tissue but include donor site morbidity. The placenta is commonly discarded after birth and has a therapeutic potential. The aim of this study was to determine if the amnion from placenta or plasma rich of growth factors (PRGF) with mononuclear cells (MNC) from umbilical cord blood (UCB), collected noninvasively, could be used as bio-constructs for autologous transplantation as an easy-accessible no cell culture-required method. Human amnion and PRGF gel were isolated and kept in culture for up to 21 days with or without small intestine submucosa (SIS). The cells in the constructs showed a robust phenotype without induced increased proliferation (Ki67) or apoptosis (caspase 3), but the constructs showed decreased integrity of the amnion-epithelial layer at the end of culture. Amnion-residing cells in the SIS constructs expressed CD73 or pan-cytokeratin, and cells in the PRGF-SIS constructs expressed CD45 and CD34. This study shows that amnion and UCB are potential sources for production of autologous grafts in the correction of congenital soft tissue defects. The constructs can be made promptly after birth with minimal handling or cell expansion needed.
Effect of Water Saturation on the Diffusion/Adsorption of 22Na and Cesium onto the Callovo-Oxfordian Claystones
Authors: Savoye Sébastien , Lefevre Serge , Fayette Agnès , Robinet Jean-Charles
Published: December 2017

The diffusion and adsorption behaviors of sodium and cesium were investigated in the Callovo-Oxfordian claystones (France) under unsaturated conditions. Through-, out-, and in-diffusion laboratory experiments were performed on intact and compacted samples. These samples were partially saturated using an osmotic method for imposed suction up to 9 MPa. This specific technique enabled us to obtain water saturation degree ranging from 81% to 100% for intact samples and from 70% to 100% for compacted materials. The results showed a very low impact of water saturation on the extent of adsorption for 22Na and cesium, onto intact and compacted materials. Such observations suggest that the saturation degrees were not low enough to limit the access of cations to adsorption sites on clay surfaces. At full saturation, enhanced diffusion for 22Na and cesium was clearly evidenced onto intact and compacted samples. Under unsaturated conditions, the diffusion behavior for Cs and 22Na was not only slower but also distinct as compared to fully saturated samples. For the intact rock and under suction of 1.9 MPa, the Cs diffusivity was reduced by a factor of 17, whereas for sodium, it was reduced by a factor of 5. Explanation was then proposed to explain such a difference.
Large Enterolith Complicating a Meckel Diverticulum Causing Obstructive Ileus in an Adolescent Male Patient
Authors: Nastos Constantinos , Giannoulopoulos Dimitrios , Georgopoulos Ioannis , Salakos Christos , Dellaportas Dionysios , Papaconstantinou Ioannis , Theodosopoulos Theodosios , Polymeneas Georgios
Published: December 2017

We present a unique case of a 16-year-old male patient who was eventually diagnosed with a large enterolith arising from a Meckel’s diverticulum. The enterolith had caused intermittent intestinal symptoms for three years before resulting in small bowel obstruction requiring surgical intervention. Meckel’s enterolith ileus is very rare with only few cases described in the literature. To our knowledge, this is only the second case of Meckel’s enterolith which had caused intermittent symptoms over a period of time, before resulting in ileus, and the first case where the intermittent symptoms lasted several years before bowel obstruction. The patient had been evaluated with colonoscopy, computerized tomography (CT), and magnetic resonance imaging enterography (MRIE); a calcified pelvic mass had been found, but no further diagnosis other than calcification was established. The patient presented at our emergency department, with symptoms of obstructive ileus and underwent exploratory laparotomy, where a large enterolith arising from a Meckel’s diverticulum (MD) was identified, causing the obstruction. A successful partial enterectomy, enterolith removal, and primary end-to-end anastomosis took place; the patient was permanently relieved from his long-standing symptoms. Consequently, complications of Meckel’s diverticulum and enterolithiasis have to be included in the differential diagnosis of abdominal complaints.
Community and Proteomic Analysis of Anaerobic Consortia Converting Tetramethylammonium to Methane
Authors: Chen Wei-Yu , Kraková Lucia , Wu Jer-Horng , Pangallo Domenico , Jeszeová Lenka , Liu Bing , Yasui Hidenari
Published: December 2017

Tetramethylammonium-degrading methanogenic consortia from a complete-mixing suspended sludge (CMSS) and an upflow anaerobic sludge blanket (UASB) reactors were studied using multiple PCR-based molecular techniques and shotgun proteomic approach. The prokaryotic 16S rRNA genes of the consortia were analyzed by quantitative PCR, high-throughput sequencing, and DGGE-cloning methods. The results showed that methanogenicarchaeawere highly predominant in both reactors but differed markedly according to community structure. Community and proteomic analysis revealed thatMethanomethylovoransandMethanosarcinawere the major players for the demethylation of methylated substrates and methane formation through the reduction pathway of methyl-S-CoM and possibly, acetyl-CoA synthase/decarbonylase-related pathways. Unlike high dominance of oneMethanomethylovoranspopulation in the CMSS reactor, diverse methylotrophicMethanosarcinaspecies inhabited in syntrophy-like association with hydrogenotrophicMethanobacteriumin the granular sludge of UASB reactor. The overall findings indicated the reactor-dependent community structures of quaternary amines degradation and provided microbial insight for the improved understanding of engineering application.
Effect of Airborne Particle Abrasion on Microtensile Bond Strength of Total-Etch Adhesives to Human Dentin
Authors: D’Amario Maurizio , Piccioni Chiara , Di Carlo Stefano , De Angelis Francesca , Caruso Silvia , Capogreco Mario
Published: December 2017

Aim of this study was to investigate a specific airborne particle abrasion pretreatment on dentin and its effects on microtensile bond strengths of four commercial total-etch adhesives. Midcoronal occlusal dentin of extracted human molars was used. Teeth were randomly assigned to 4 groups according to the adhesive system used: OptiBond FL (FL), OptiBond Solo Plus (SO), Prime & Bond (PB), and Riva Bond LC (RB). Specimens from each group were further divided into two subgroups: control specimens were treated with adhesive procedures; abraded specimens were pretreated with airborne particle abrasion using 50 μm Al2O3before adhesion. After bonding procedures, composite crowns were incrementally built up. Specimens were sectioned perpendicular to adhesive interface to produce multiple beams, which were tested under tension until failure. Data were statistically analysed. Failure mode analysis was performed. Overall comparison showed significant increase in bond strength (p<0.001) between abraded and no-abraded specimens, independently of brand. Intrabrand comparison showed statistical increase when abraded specimens were tested compared to no-abraded ones, with the exception of PB that did not show such difference. Distribution of failure mode was relatively uniform among all subgroups. Surface treatment by airborne particle abrasion with Al2O3particles can increase the bond strength of total-etch adhesives.
Roles of Endoplasmic Reticulum Stress in NECA‐Induced Cardioprotection against Ischemia/Reperfusion Injury
Authors: Xing Fengmei , Han Hui , He Yonggui , Zhang Yidong , Jing Liwei , Xu Zhelong , Xi Jinkun
Published: December 2017

Objective. This study aimed to investigate whether the nonselective A2 adenosine receptor agonist NECA induces cardioprotection against myocardial ischemia/reperfusion (I/R) injury via glycogen synthase kinase 3β (GSK‐3β) and the mitochondrial permeability transition pore (mPTP) through inhibition of endoplasmic reticulum stress (ERS). Methods and Results. H9c2 cells were exposed to H2O2 for 20 minutes. NECA significantly prevented H2O2‐induced TMRE fluorescence reduction, indicating that NECA inhibited the mPTP opening. NECA blocked H2O2‐induced GSK‐3β phosphorylation and GRP94 expression. NECA increased GSK‐3β phosphorylation and decreased GRP94 expression, which were prevented by both ERS inductor 2‐DG and PKG inhibitor KT5823, suggesting that NECA may induce cardioprotection through GSK‐3β and cGMP/PKG via ERS. In isolated rat hearts, both NECA and the ERS inhibitor TUDCA decreased myocardial infarction, increased GSK‐3β phosphorylation, and reversed GRP94 expression at reperfusion, suggesting that NECA protected the heart by inhibiting GSK‐3β and ERS. Transmission electron microscopy showed that NECA and TUDCA reduced mitochondrial swelling and endoplasmic reticulum expansion, further supporting that NECA protected the heart by preventing the mPTP opening and ERS. Conclusion. These data suggest that NECA prevents the mPTP opening through inactivation of GSK‐3β via ERS inhibition. The cGMP/PKG signaling pathway is responsible for GSK‐3β inactivation by NECA.
Study on Crystallization and Magnetic Property Deviation of Ni-Zn-Cu Ferrite Depending on the State of the Starting Material in the Annealing Process
Authors: Yang Su-won , Jeong Kwang-pil , Kim Jeong-gon
Published: December 2017

The spinel structure of the nanosize powder (Ni0.3Zn0.3Cu0.4Fe2O4) substituted by Ni, Zn, and Cu was fabricated by the sol-gel process. Changes in weight, crystal formation, and magnetic properties were observed by XRD, TG-DTA, VSM in the annealing process of the sol and gel. The saturation magnetization of the sol showed 54.8–58.6 emu/g at 500–800°C, and the gel showed 52.3–56.8 emu/g at 600–800°C. The coercive force of the sol decreased in the range −136 Oe to −11.4 Oe at 500–800°C, and the gel decreased in the range −95 Oe to −44 Oe at 600–800°C. Therefore, the deviation of the annealing temperature of the nanopowder fabricated in the sol process and the gel process was about 100°C.
Treatment of Extensively Comminuted Mandibular Fracture with the Aid of a Condylar Positioning Device
Authors: Nazimi Abd Jabar , Ezulia Tengku , Rajaran Jothi Raamahlingam , Mohd Yunus Siti Salmiah , Nabil Syed
Published: December 2017

We describe a case of extensively comminuted mandibular fracture that extends bilaterally to the angle of mandible successfully treated with the use of condylar positioning device (CPD). This simple, yet effective, technique that almost exclusively described in orthognathic surgery is useful when advance surgical techniques such as pre- or intraoperative landmark identification may not be readily available. CPD technique optimizes the manual manipulations of the comminuted distal segments during fracture reduction and internal fixation. At the same time, it allows greater control of the proximal segments to avoid further surgical complication.
Comparison between theHLA-B∗58 : 01Allele and Single-Nucleotide Polymorphisms in Chromosome 6 for Prediction of Allopurinol-Induced Severe Cutaneous Adverse Reactions
Authors: Saksit Niwat , Nakkam Nontaya , Konyoung Parinya , Khunarkornsiri Usanee , Tassaneeyakul Wongwiwat , Chumworathayi Pansu , Kanjanawart Sirimas , Sukasem Chonlaphat , Sangviroon Alisara , Pattanacheewapull Oranuch , Tassaneeyakul Wichittra
Published: December 2017

Severe cutaneous adverse drug reactions (SCARs) are life-threatening reactions. The strong association between theHLA-B∗58 : 01allele and allopurinol-induced SCARs is well recognized. Screening forHLA-B∗58 : 01allele before prescribing allopurinol in some populations has been recommended. Several single-nucleotide polymorphisms (SNPs) in chromosome 6 have been found to be tightly linked with theHLAallele, and these SNPs have been proposed as surrogate markers of theHLA-B∗58 : 01allele. This study aimed to evaluate the association between three SNPs in chromosome 6 and allopurinol-induced SCARs in a Thai population. The linkage disequilibrium between theHLA-B∗58 : 01allele and these SNPs was also evaluated. Results showed that three SNPs including rs9263726, rs2734583, and rs3099844 were significantly associated with allopurinol-induced SCARs but with a lower degree of association when compared with theHLA-B∗58 : 01allele. The sensitivity, specificity, PPV, and NPV of these SNPs were comparable to those of theHLA-B∗58 : 01allele. Although detection of the SNP is simpler and less expensive compared with that of theHLA-B∗58 : 01allele, these SNPs were not perfectly linked with theHLA-B∗58 : 01allele. Screening using these SNPs as surrogate markers of theHLA-B∗58 : 01allele to avoid SCARs prior to allopurinol administration needs caution because of their imperfect linkage with theHLA-B∗58 : 01allele.
Hydroxychloroquine Use in Lupus Patients during Pregnancy Is Associated with Longer Pregnancy Duration in Preterm Births
Authors: Kroese S. J. , de Hair M. J. H. , Limper M. , Lely A. T. , van Laar J. M. , Derksen R. H. W. M. , Fritsch-Stork R. D. E.
Published: December 2017

Objective. To investigate the effect of hydroxychloroquine (HCQ) in pregnant women with systemic lupus erythematosus (SLE). Methods. In SLE pregnancies of a single Dutch center (2000–2015), lupus activity and flares before and during pregnancy and postpartum were assessed using the SLE Disease Activity Index (SLEDAI)/SLEPDAI (SLEDAI adjusted for pregnancy). The association between HCQ use and pregnancy outcomes (early spontaneous abortion, fetal death, and preterm and term live birth) was analyzed using generalized estimating equations (GEE) accounting for the occurrence of multiple pregnancies per patient. Analyses were adjusted for antiphospholipid antibody (aPL) status. Results. 110 pregnancies (63 mostly Caucasian patients) were included, of which, in 30, HCQ was used; overall occurrence of flares was low (non-HCQ group: 5 mild (6.4%) and 2 severe (2.6%); HCQ group: 2 mild (6.7%) and no severe flares). The HCQ group showed a trend towards lower dosage of prednisone (OR 0.2 (95% CI 0.0–1.4); p=0.10). Pregnancy outcomes were comparable between groups. Among preterm live births, pregnancy duration was significantly longer in HCQ users (2.4 weeks (95% CI 1.0–3.8; p≤0.001)). Conclusion. HCQ use was associated with longer pregnancy duration in the vulnerable preterm birth population, underscoring the beneficial effect of HCQ use during pregnancy.