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Sample records for inhibitory controls dnic

  1. Diffuse noxious inhibitory controls and nerve injury: restoring an imbalance between descending monoamine inhibitions and facilitations.

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    Bannister, Kirsty; Patel, Ryan; Goncalves, Leonor; Townson, Louisa; Dickenson, Anthony H

    2015-09-01

    Diffuse noxious inhibitory controls (DNICs) utilize descending inhibitory controls through poorly understood brain stem pathways. The human counterpart, conditioned pain modulation, is reduced in patients with neuropathy aligned with animal data showing a loss of descending inhibitory noradrenaline controls together with a gain of 5-HT3 receptor-mediated facilitations after neuropathy. We investigated the pharmacological basis of DNIC and whether it can be restored after neuropathy. Deep dorsal horn neurons were activated by von Frey filaments applied to the hind paw, and DNIC was induced by a pinch applied to the ear in isoflurane-anaesthetized animals. Spinal nerve ligation was the model of neuropathy. Diffuse noxious inhibitory control was present in control rats but abolished after neuropathy. α2 adrenoceptor mechanisms underlie DNIC because the antagonists, yohimbine and atipamezole, markedly attenuated this descending inhibition. We restored DNIC in spinal nerve ligated animals by blocking 5-HT3 descending facilitations with the antagonist ondansetron or by enhancing norepinephrine modulation through the use of reboxetine (a norepinephrine reuptake inhibitor, NRI) or tapentadol (μ-opioid receptor agonist and NRI). Additionally, ondansetron enhanced DNIC in normal animals. Diffuse noxious inhibitory controls are reduced after peripheral nerve injury illustrating the central impact of neuropathy, leading to an imbalance in descending excitations and inhibitions. Underlying noradrenergic mechanisms explain the relationship between conditioned pain modulation and the use of tapentadol and duloxetine (a serotonin, NRI) in patients. We suggest that pharmacological strategies through manipulation of the monoamine system could be used to enhance DNIC in patients by blocking descending facilitations with ondansetron or enhancing norepinephrine inhibitions, so possibly reducing chronic pain.

  2. Electroacupuncture Potentiates Cannabinoid Receptor-Mediated Descending Inhibitory Control in a Mouse Model of Knee Osteoarthritis

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    Xiao-Cui Yuan

    2018-04-01

    Full Text Available Knee osteoarthritis (KOA is a highly prevalent, chronic joint disorder, which can lead to chronic pain. Although electroacupuncture (EA is effective in relieving chronic pain in the clinic, the involved mechanisms remain unclear. Reduced diffuse noxius inhibitory controls (DNIC function is associated with chronic pain and may be related to the action of endocannabinoids. In the present study, we determined whether EA may potentiate cannabinoid receptor-mediated descending inhibitory control and inhibit chronic pain in a mouse model of KOA. We found that the optimized parameters of EA inhibiting chronic pain were the low frequency and high intensity (2 Hz + 1 mA. EA reversed the reduced expression of CB1 receptors and the 2-arachidonoylglycerol (2-AG level in the midbrain in chronic pain. Microinjection of the CB1 receptor antagonist AM251 into the ventrolateral periaqueductal gray (vlPAG can reversed the EA effect on pain hypersensitivity and DNIC function. In addition, CB1 receptors on GABAergic but not glutamatergic neurons are involved in the EA effect on DNIC function and descending inhibitory control of 5-HT in the medulla, thus inhibiting chronic pain. Our data suggest that endocannabinoid (2-AG-CB1R-GABA-5-HT may be a novel signaling pathway involved in the effect of EA improving DNIC function and inhibiting chronic pain.

  3. Determinants of endogenous analgesia magnitude in a diffuse noxious inhibitory control (DNIC) paradigm: do conditioning stimulus painfulness, gender and personality variables matter?

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    Granot, Michal; Weissman-Fogel, Irit; Crispel, Yonathan; Pud, Dorit; Granovsky, Yelena; Sprecher, Elliot; Yarnitsky, David

    2008-05-01

    Descending modulation of pain can be demonstrated psychophysically by dual pain stimulation. This study evaluates in 31 healthy subjects the association between parameters of the conditioning stimulus, gender and personality, and the endogenous analgesia (EA) extent assessed by diffuse noxious inhibitory control (DNIC) paradigm. Contact heat pain was applied as the test stimulus to the non-dominant forearm, with stimulation temperature at a psychophysical intensity score of 60 on a 0-100 numerical pain scale. The conditioning stimulus was a 60s immersion of the dominant hand in cold (12, 15, 18 degrees C), hot (44 and 46.5 degrees C), or skin temperature (33 degrees C) water. The test stimulus was repeated on the non-dominant hand during the last 30s of the conditioning immersion. EA extent was calculated as the difference between pain scores of the two test stimuli. State and trait anxiety and pain catastrophizing scores were assessed prior to stimulation. EA was induced only for the pain-generating conditioning stimuli at 46.5 degrees C (p=0.011) and 12 degrees C (p=0.003). EA was independent of conditioning pain modality, or personality, but a significant gender effect was found, with greater EA response in males. Importantly, pain scores of the conditioning stimuli were not correlated with EA extent. The latter is based on both our study population, and on additional 82 patients, who participated in another study, in which EA was induced by immersion at 46.5 degrees C. DNIC testing, thus, seems to be relatively independent of the stimulation conditions, making it an easy to apply tool, suitable for wide range applications in pain psychophysics.

  4. An investigation into the inhibitory function of serotonin in diffuse noxious inhibitory controls in the neuropathic rat.

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    Bannister, K; Lockwood, S; Goncalves, L; Patel, R; Dickenson, A H

    2017-04-01

    Following neuropathy α2-adrenoceptor-mediated diffuse noxious inhibitory controls (DNIC), whereby a noxious conditioning stimulus inhibits the activity of spinal wide dynamic range (WDR) neurons, are abolished, and spinal 5-HT7 receptor densities are increased. Here, we manipulate spinal 5-HT content in spinal nerve ligated (SNL) animals and investigate which 5-HT receptor mediated actions predominate. Using in vivo electrophysiology we recorded WDR neuronal responses to von frey filaments applied to the hind paw before, and concurrent to, a noxious ear pinch (the conditioning stimulus) in isoflurane-anaesthetised rats. The expression of DNIC was quantified as a reduction in WDR neuronal firing in the presence of conditioning stimulus and was investigated in SNL rats following spinal application of (1) selective serotonin reuptake inhibitors (SSRIs) citalopram or fluoxetine, or dual application of (2) SSRI plus 5-HT7 receptor antagonist SB269970, or (3) SSRI plus α2 adrenoceptor antagonist atipamezole. DNIC were revealed in SNL animals following spinal application of SSRI, but this effect was abolished upon joint application of SSRI plus SB269970 or atipamezole. We propose that in SNL animals the inhibitory actions (quantified as the presence of DNIC) of excess spinal 5-HT (presumed present following application of SSRI) were mediated via 5-HT7 receptors. The anti-nociception depends upon an underlying tonic noradrenergic inhibitory tone via the α2-adrenoceptor. Following neuropathy enhanced spinal serotonin availability switches the predominant spinal 5-HT receptor-mediated actions but also alters noradrenergic signalling. We highlight the therapeutic complexity of SSRIs and monoamine modulators for the treatment of neuropathic pain. © 2016 European Pain Federation - EFIC®.

  5. Does Acupuncture Needling Induce Analgesic Effects Comparable to Diffuse Noxious Inhibitory Controls?

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    Juerg Schliessbach

    2012-01-01

    Full Text Available Diffuse noxious inhibitory control (DNIC is described as one possible mechanism of acupuncture analgesia. This study investigated the analgesic effect of acupuncture without stimulation compared to nonpenetrating sham acupuncture (NPSA and cold-pressor-induced DNIC. Forty-five subjects received each of the three interventions in a randomized order. The analgesic effect was measured using pressure algometry at the second toe before and after each of the interventions. Pressure pain detection threshold (PPDT rose from 299 kPa (SD 112 kPa to 364 kPa (SD 144, 353 kPa (SD 135, and 467 kPa (SD 168 after acupuncture, NPSA, and DNIC test, respectively. There was no statistically significant difference between acupuncture and NPSA at any time, but a significantly higher increase of PPDT in the DNIC test compared to acupuncture and NPSA. PPDT decreased after the DNIC test, whereas it remained stable after acupuncture and NPSA. Acupuncture needling at low pain stimulus intensity showed a small analgesic effect which did not significantly differ from placebo response and was significantly less than a DNIC-like effect of a painful noninvasive stimulus.

  6. Prediction of chronic post-operative pain: pre-operative DNIC testing identifies patients at risk.

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    Yarnitsky, David; Crispel, Yonathan; Eisenberg, Elon; Granovsky, Yelena; Ben-Nun, Alon; Sprecher, Elliot; Best, Lael-Anson; Granot, Michal

    2008-08-15

    Surgical and medical procedures, mainly those associated with nerve injuries, may lead to chronic persistent pain. Currently, one cannot predict which patients undergoing such procedures are 'at risk' to develop chronic pain. We hypothesized that the endogenous analgesia system is key to determining the pattern of handling noxious events, and therefore testing diffuse noxious inhibitory control (DNIC) will predict susceptibility to develop chronic post-thoracotomy pain (CPTP). Pre-operative psychophysical tests, including DNIC assessment (pain reduction during exposure to another noxious stimulus at remote body area), were conducted in 62 patients, who were followed 29.0+/-16.9 weeks after thoracotomy. Logistic regression revealed that pre-operatively assessed DNIC efficiency and acute post-operative pain intensity were two independent predictors for CPTP. Efficient DNIC predicted lower risk of CPTP, with OR 0.52 (0.33-0.77 95% CI, p=0.0024), i.e., a 10-point numerical pain scale (NPS) reduction halves the chance to develop chronic pain. Higher acute pain intensity indicated OR of 1.80 (1.28-2.77, p=0.0024) predicting nearly a double chance to develop chronic pain for each 10-point increase. The other psychophysical measures, pain thresholds and supra-threshold pain magnitudes, did not predict CPTP. For prediction of acute post-operative pain intensity, DNIC efficiency was not found significant. Effectiveness of the endogenous analgesia system obtained at a pain-free state, therefore, seems to reflect the individual's ability to tackle noxious events, identifying patients 'at risk' to develop post-intervention chronic pain. Applying this diagnostic approach before procedures that might generate pain may allow individually tailored pain prevention and management, which may substantially reduce suffering.

  7. Water-Soluble Dinitrosyl Iron Complex (DNIC): a Nitric Oxide Vehicle Triggering Cancer Cell Death via Apoptosis.

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    Wu, Shou-Cheng; Lu, Chung-Yen; Chen, Yi-Lin; Lo, Feng-Chun; Wang, Ting-Yin; Chen, Yu-Jen; Yuan, Shyng-Shiou; Liaw, Wen-Feng; Wang, Yun-Ming

    2016-09-19

    Nitric oxide (NO) is an important cellular signaling molecule that modulates various physiological activities. Angiogenesis-promoting activities of NO-donor drugs have been explored in both experimental and clinical studies. In this study, a structurally well characterized and water-soluble neutral {Fe(NO)2}(9) DNIC [(S(CH2)2OH)(S(CH2)2NH3)Fe(NO)2] (DNIC 2) was synthesized to serve as a NO-donor species. The antitumor activity of DNIC 2 was determined by MTT assay, confocal imaging, and Annexin-V/PI staining. The IC50 values of DNIC 2 were 18.8, 42.9, and 38.6 μM for PC-3, SKBR-3, and CRL5866 tumor cells, respectively. Moreover, DNIC 2 promoted apoptotic cell death via activation of apoptosis-associated proteins and inhibition of survival associated proteins. In particular, DNIC 2 treatment suppressed PC-3 tumor growth by 2.34- and 19.3-fold at 7 and 21 days, in comparison with the control group. These results indicate that water-soluble DNIC 2 may serve as a promising drug for cancer therapy.

  8. The plasticity of descending controls in pain: translational probing.

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    Bannister, Kirsty; Dickenson, A H

    2017-07-01

    Descending controls, comprising pathways that originate in midbrain and brainstem regions and project onto the spinal cord, have long been recognised as key links in the multiple neural networks that interact to produce the overall pain experience. There is clear evidence from preclinical and clinical studies that both peripheral and central sensitisation play important roles in determining the level of pain perceived. Much emphasis has been put on spinal cord mechanisms in central excitability, but it is now becoming clear that spinal hyperexcitability can be regulated by descending pathways from the brain that originate from predominantly noradrenergic and serotonergic systems. One pain can inhibit another. In this respect diffuse noxious inhibitory controls (DNIC) are a unique form of endogenous descending inhibitory pathway since they can be easily evoked and quantified in animals and man. The spinal pharmacology of pathways that subserve DNIC are complicated; in the normal situation these descending controls produce a final inhibitory effect through the actions of noradrenaline at spinal α 2 -adrenoceptors, although serotonin, acting on facilitatory spinal 5-HT 3 receptors, influences the final expression of DNIC also. These descending pathways are altered in neuropathy and the effects of excess serotonin may now become inhibitory through activation of spinal 5-HT 7 receptors. Conditioned pain modulation (CPM) is the human counterpart of DNIC and requires a descending control also. Back and forward translational studies between DNIC and CPM, gauged between bench and bedside, are key for the development of analgesic therapies that exploit descending noradrenergic and serotonergic control pathways. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

  9. Unusual Synthetic Pathway for an {Fe(NO)2}9 Dinitrosyl Iron Complex (DNIC) and Insight into DNIC Electronic Structure via Nuclear Resonance Vibrational Spectroscopy

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    Speelman, Amy L.; Zhang, Bo; Silakov, Alexey; Skodje, Kelsey M.; Alp, E. Ercan; Zhao, Jiyong; Hu, Michael Y.; Kim, Eunsuk; Krebs, Karsten; Lehnert, Nicolai

    2016-06-06

    Dinitrosyl iron complexes (DNICs) are among the most abundant NO-derived cellular species. Monomeric DNICs can exist in the {Fe(NO)2}9 or {Fe(NO)2}10 oxidation state (in the Enemark -Feltham notation). However, experimental studies of analogous DNICs in both oxidation states are rare, which prevents a thorough understanding of the di ff erences in the electronic structures of these species. Here, the {Fe(NO)2}9 DNIC [Fe(dmp)(NO)2](OTf) ( 1 ; dmp = 2,9-dimethyl-1,10- phenanthroline) is synthesized from a ferrous precursor via an unusual pathway, involving disproportionation of an {FeNO}7 complex to yield the {Fe(NO)2}9 DNIC and a ferric species, which is subsequently reduced by NO gas to generate a ferrous complex that re-enters the reaction cycle. In contrast to most {Fe(NO)2}9 DNICs with neutral N-donor ligands, 1 exhibits high solution stability and can be characterized structurally and spectroscopically. Reduction of 1 yields the corresponding {Fe(NO)2}10 DNIC [Fe(dmp)(NO)2](2). The Mo ssbauer isomer shift of 2 is 0.08 mm/s smaller than that of 1 , which indicates that the iron center is slightly more oxidized in the reduced complex. The nuclear resonance vibrational spectra (NRVS) of 1 and 2 are distinct and provide direct experimental insight into di ff erences in bonding in these complexes. In particular, the symmetric out-of-plane Fe -N - O bending mode is shifted to higher energy by 188 cm-1 in 2 in comparison to 1 . Using quantum chemistry centered normal coordinate analysis (QCC-NCA), this is shown to arise from an increase in Fe - NO bond order and a sti ff ening of the Fe(NO)2 unit upon reduction of 1 to 2 . DFT calculations demonstrate that the changes in bonding arise from an iron- centered reduction which leads to a distinct increase in Fe - NO π -back-bonding in

  10. Effect of ketamine on endogenous pain modulation in healthy volunteers.

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    Niesters, Marieke; Dahan, Albert; Swartjes, Maarten; Noppers, Ingeborg; Fillingim, Roger B; Aarts, Leon; Sarton, Elise Y

    2011-03-01

    Inhibitory and facilitatory descending pathways, originating at higher central nervous system sites, modulate activity of dorsal horn nociceptive neurons, and thereby influence pain perception. Dysfunction of inhibitory pain pathways or a shift in the balance between pain facilitation and pain inhibition has been associated with the development of chronic pain. The N-methyl-d-aspartate receptor antagonist ketamine has a prolonged analgesic effect in chronic pain patients. This effect is due to desensitization of sensitized N-methyl-d-aspartate receptors. Additionally, ketamine may modulate or enhance endogenous inhibitory control of pain perception. Diffuse noxious inhibitory control (DNIC) and offset analgesia (OA) are 2 mechanisms involved in descending inhibition. The present study investigates the effect of a ketamine infusion on subsequent DNIC and OA responses to determine whether ketamine has an influence on descending pain control. Ten healthy subjects (4 men/6 women) received a 1-hour placebo or S(+)-ketamine (40mg per 70kg) infusion on 2 separate occasions in random order. Upon the termination of the infusion, DNIC and OA responses were obtained. After placebo treatment, significant descending inhibition of pain responses was present for DNIC and OA. In contrast, after ketamine infusion, no DNIC was observed, but rather a significant facilitatory pain response (Ppain inhibition and pain facilitation was shifted by ketamine towards pain facilitation. The absence of an effect of ketamine on OA indicates differences in the mechanisms and neurotransmitter influences between OA and DNIC. Diffuse noxious inhibitory control responses following a 1-hour low-dose ketamine treatment displayed facilitation of pain in response to experimental noxious thermal stimulation. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  11. Lateralized kappa opioid receptor signaling from the amygdala central nucleus promotes stress-induced functional pain.

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    Nation, Kelsey M; De Felice, Milena; Hernandez, Pablo I; Dodick, David W; Neugebauer, Volker; Navratilova, Edita; Porreca, Frank

    2018-05-01

    The response of diffuse noxious inhibitory controls (DNIC) is often decreased, or lost, in stress-related functional pain syndromes. Because the dynorphin/kappa opioid receptor (KOR) pathway is activated by stress, we determined its role in DNIC using a model of stress-induced functional pain. Male, Sprague-Dawley rats were primed for 7 days with systemic morphine resulting in opioid-induced hyperalgesia. Fourteen days after priming, when hyperalgesia was resolved, rats were exposed to environmental stress and DNIC was evaluated by measuring hind paw response threshold to noxious pressure (test stimulus) after capsaicin injection in the forepaw (conditioning stimulus). Morphine priming without stress did not alter DNIC. However, stress produced a loss of DNIC in morphine-primed rats in both hind paws that was abolished by systemic administration of the KOR antagonist, nor-binaltorphimine (nor-BNI). Microinjection of nor-BNI into the right, but not left, central nucleus of the amygdala (CeA) prevented the loss of DNIC in morphine-primed rats. Diffuse noxious inhibitory controls were not modulated by bilateral nor-BNI in the rostral ventromedial medulla. Stress increased dynorphin content in both the left and right CeA of primed rats, reaching significance only in the right CeA; no change was observed in the rostral ventromedial medulla or hypothalamus. Although morphine priming alone is not sufficient to influence DNIC, it establishes a state of latent sensitization that amplifies the consequences of stress. After priming, stress-induced dynorphin/KOR signaling from the right CeA inhibits DNIC in both hind paws, likely reflecting enhanced descending facilitation that masks descending inhibition. Kappa opioid receptor antagonists may provide a new therapeutic strategy for stress-related functional pain disorders.

  12. Do Children with Better Inhibitory Control Donate More? Differentiating between Early and Middle Childhood and Cool and Hot Inhibitory Control

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    Jian Hao

    2017-12-01

    Full Text Available Inhibitory control may play an important part in prosocial behavior, such as donating behavior. However, it is not clear at what developmental stage inhibitory control becomes associated with donating behavior and which aspects of inhibitory control are related to donating behavior during development in early to middle childhood. The present study aimed to clarify these issues with two experiments. In Experiment 1, 103 3- to 5-year-old preschoolers completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results indicated that there were no relationships between cool or hot inhibitory control and donating behavior in the whole group and each age group of the preschoolers. In Experiment 2, 140 elementary school children in Grades 2, 4, and 6 completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results showed that inhibitory control was positively associated with donating behavior in the whole group. Cool and hot inhibitory control respectively predicted donating behavior in the second and sixth graders. Therefore, the present study reveals that donating behavior increasingly relies on specific inhibitory control, i.e., hot inhibitory control as children grow in middle childhood.

  13. Preschool Inhibitory Control Predicts ADHD Group Status and Inhibitory Weakness in School.

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    Jacobson, Lisa A; Schneider, Heather; Mahone, E Mark

    2017-12-26

    Discriminative utility of performance measures of inhibitory control was examined in preschool children with and without ADHD to determine whether performance measures added to diagnostic prediction and to prediction of informant-rated day-to-day executive function. Children ages 4-5 years (N = 105, 61% boys; 54 ADHD, medication-naïve) were assessed using performance measures (Auditory Continuous Performance Test for Preschoolers-Commission errors, Conflicting Motor Response Test, NEPSY Statue) and caregiver (parent, teacher) ratings of inhibition (Behavior Rating Inventory of Executive Function-Preschool version). Performance measures and parent and teacher reports of inhibitory control significantly and uniquely predicted ADHD group status; however, performance measures did not add to prediction of group status beyond parent reports. Performance measures did significantly predict classroom inhibitory control (teacher ratings), over and above parent reports of inhibitory control. Performance measures of inhibitory control may be adequate predictors of ADHD status and good predictors of young children's classroom inhibitory control, demonstrating utility as components of clinical assessments. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Mechanism of inhibition of catalase by nitro and nitroso compounds.

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    Titov, V Yu; Petrenko, Yu M; Vanin, A F

    2008-01-01

    Dinitrosyl iron complexes (DNIC) with thiolate ligands and S-nitrosothiols, which are NO and NO+ donors, share the earlier demonstrated ability of nitrite for inhibition of catalase. The efficiency of inhibition sharply (by several orders in concentration of these agents) increases in the presence of chloride, bromide, and thiocyanate. The nitro compounds tested--nitroarginine, nitroglycerol, nitrophenol, and furazolidone--gained the same inhibition ability after incubation with ferrous ions and thiols. This is probably the result of their transformation into DNIC. None of these substances lost the inhibitory effect in the presence of the well known NO scavenger oxyhemoglobin. This fact suggests that NO+ ions rather than neutral NO molecules are responsible for the enzyme inactivation due to nitrosation of its structures. The enhancement of catalase inhibition in the presence of halide ions and thiocyanate might be caused by nitrosyl halide formation. The latter protected nitrosonium ions against hydrolysis, thereby ensuring their transfer to the targets in enzyme molecules. The addition of oxyhemoglobin plus iron chelator o-phenanthroline destroying DNIC sharply attenuated the inhibitory effect of DNIC on catalase. o-Phenanthroline added alone did not influence this effect. Oxyhemoglobin is suggested to scavenge nitrosonium ions released from decomposing DNIC, thereby preventing catalase nitrosation. The mixture of oxyhemoglobin and o-phenanthroline did not affect the inhibitory action of nitrite or S-nitrosothiols on catalase.

  15. Impulsivity: A deficiency of inhibitory control?

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    Lansbergen, M.M.

    2007-01-01

    Impulsivity has been defined as acting without thinking. Impulsivity can be quantified by impulsivity questionnaires, but also by behavioral paradigms which tax inhibitory control. Previous research has repeatedly demonstrated deficient inhibitory control in psychopathological samples characterized

  16. Voluntary inhibitory motor control over involuntary tic movements.

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    Ganos, Christos; Rothwell, John; Haggard, Patrick

    2018-03-06

    Inhibitory control is crucial for normal adaptive motor behavior. In hyperkinesias, such as tics, disinhibition within the cortico-striato-thalamo-cortical loops is thought to underlie the presence of involuntary movements. Paradoxically, tics are also subject to voluntary inhibitory control. This puzzling clinical observation questions the traditional definition of tics as purely involuntary motor behaviors. Importantly, it suggests novel insights into tic pathophysiology. In this review, we first define voluntary inhibitory tic control and compare it with other notions of tic control from the literature. We then examine the association between voluntary inhibitory tic control with premonitory urges and review evidence linking voluntary tic inhibition to other forms of executive control of action. We discuss the somatotopic selectivity and the neural correlates of voluntary inhibitory tic control. Finally, we provide a scientific framework with regard to the clinical relevance of the study of voluntary inhibitory tic control within the context of the neurodevelopmental disorder of Tourette syndrome. We identify current knowledge gaps that deserve attention in future research. © 2018 International Parkinson and Movement Disorder Society. © 2018 International Parkinson and Movement Disorder Society.

  17. Flexible brain network reconfiguration supporting inhibitory control.

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    Spielberg, Jeffrey M; Miller, Gregory A; Heller, Wendy; Banich, Marie T

    2015-08-11

    The ability to inhibit distracting stimuli from interfering with goal-directed behavior is crucial for success in most spheres of life. Despite an abundance of studies examining regional brain activation, knowledge of the brain networks involved in inhibitory control remains quite limited. To address this critical gap, we applied graph theory tools to functional magnetic resonance imaging data collected while a large sample of adults (n = 101) performed a color-word Stroop task. Higher demand for inhibitory control was associated with restructuring of the global network into a configuration that was more optimized for specialized processing (functional segregation), more efficient at communicating the output of such processing across the network (functional integration), and more resilient to potential interruption (resilience). In addition, there were regional changes with right inferior frontal sulcus and right anterior insula occupying more central positions as network hubs, and dorsal anterior cingulate cortex becoming more tightly coupled with its regional subnetwork. Given the crucial role of inhibitory control in goal-directed behavior, present findings identifying functional network organization supporting inhibitory control have the potential to provide additional insights into how inhibitory control may break down in a wide variety of individuals with neurological or psychiatric difficulties.

  18. Self-restraint spillover: Inhibitory control disrupts appetite regulation among ruminators.

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    Schlinkert, Caroline; Koole, Sander L

    2017-10-23

    People can use inhibitory control to temporarily inhibit their personal preferences to achieve their long-term goals. According to the ego fixation model (Koole et al., 2014), ruminators have difficulties relaxing inhibitory control, leading them to continue inhibiting their personal needs, even when this is no longer required by the situation. Inhibitory control may thus disrupt healthy appetite regulation among ruminators. Among 324 Dutch undergraduate students (218 women; M age  = 21.5), different inhibitory control states were manipulated by varying whether or not participants exerted inhibitory control (Study 1) or priming high versus low inhibitory control (Study 2). All participants then performed a food-tasting task. Healthy appetite regulation was defined as a positive correlation between level of food deprivation and preference for high-calorie foods. For taste ratings, the interaction between inhibitory control and rumination was significant in each study: Inhibitory control disrupted healthy appetite regulation in taste preferences among ruminators, but not among non-ruminators. For eating behavior, the same interaction effect was significant when the two studies were combined. Inhibitory control disrupts healthy appetite regulation among ruminators. These findings suggest the need for caution in interventions that rely on inhibitory control, especially among samples with compulsive thought tendencies. © 2017 Wiley Periodicals, Inc.

  19. Self-reported impulsivity and inhibitory control in problem gamblers.

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    Lorains, Felicity K; Stout, Julie C; Bradshaw, John L; Dowling, Nicki A; Enticott, Peter G

    2014-01-01

    Impulsivity is considered a core feature of problem gambling; however, self-reported impulsivity and inhibitory control may reflect disparate constructs. We examined self-reported impulsivity and inhibitory control in 39 treatment-seeking problem gamblers and 41 matched controls using a range of self-report questionnaires and laboratory inhibitory control tasks. We also investigated differences between treatment-seeking problem gamblers who prefer strategic (e.g., sports betting) and nonstrategic (e.g., electronic gaming machines) gambling activities. Treatment-seeking problem gamblers demonstrated elevated self-reported impulsivity, more go errors on the Stop Signal Task, and a lower gap score on the Random Number Generation task than matched controls. However, overall we did not find strong evidence that treatment-seeking problem gamblers are more impulsive on laboratory inhibitory control measures. Furthermore, strategic and nonstrategic problem gamblers did not differ from their respective controls on either self-reported impulsivity questionnaires or laboratory inhibitory control measures. Contrary to expectations, our results suggest that inhibitory dyscontrol may not be a key component for some treatment-seeking problem gamblers.

  20. Bilingual Contexts Modulate the Inhibitory Control Network

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    Jing Yang

    2018-03-01

    Full Text Available The present functional magnetic resonance imaging (fMRI study investigated influences of language contexts on inhibitory control and the underlying neural processes. Thirty Cantonese–Mandarin–English trilingual speakers, who were highly proficient in Cantonese (L1 and Mandarin (L2, and moderately proficient in English (L3, performed a picture-naming task in three dual-language contexts (L1-L2, L2-L3, and L1-L3. After each of the three naming tasks, participants performed a flanker task, measuring contextual effects on the inhibitory control system. Behavioral results showed a typical flanker effect in the L2-L3 and L1-L3 condition, but not in the L1-L2 condition, which indicates contextual facilitation on inhibitory control performance by the L1-L2 context. Whole brain analysis of the fMRI data acquired during the flanker tasks showed more neural activations in the right prefrontal cortex and subcortical areas in the L2-L3 and L1-L3 condition on one hand as compared to the L1-L2 condition on the other hand, suggesting greater involvement of the cognitive control areas when participants were performing the flanker task in L2-L3 and L1-L3 contexts. Effective connectivity analyses displayed a cortical-subcortical-cerebellar circuitry for inhibitory control in the trilinguals. However, contrary to the right-lateralized network in the L1-L2 condition, functional networks for inhibitory control in the L2-L3 and L1-L3 condition are less integrated and more left-lateralized. These findings provide a novel perspective for investigating the interaction between bilingualism (multilingualism and inhibitory control by demonstrating instant behavioral effects and neural plasticity as a function of changes in global language contexts.

  1. Do detour tasks provide accurate assays of inhibitory control?

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    Whiteside, Mark A.; Laker, Philippa R.; Beardsworth, Christine E.

    2018-01-01

    Transparent Cylinder and Barrier tasks are used to purportedly assess inhibitory control in a variety of animals. However, we suspect that performances on these detour tasks are influenced by non-cognitive traits, which may result in inaccurate assays of inhibitory control. We therefore reared pheasants under standardized conditions and presented each bird with two sets of similar tasks commonly used to measure inhibitory control. We recorded the number of times subjects incorrectly attempted to access a reward through transparent barriers, and their latencies to solve each task. Such measures are commonly used to infer the differential expression of inhibitory control. We found little evidence that their performances were consistent across the two different Putative Inhibitory Control Tasks (PICTs). Improvements in performance across trials showed that pheasants learned the affordances of each specific task. Critically, prior experience of transparent tasks, either Barrier or Cylinder, also improved subsequent inhibitory control performance on a novel task, suggesting that they also learned the general properties of transparent obstacles. Individual measures of persistence, assayed in a third task, were positively related to their frequency of incorrect attempts to solve the transparent inhibitory control tasks. Neophobia, Sex and Body Condition had no influence on individual performance. Contrary to previous studies of primates, pheasants with poor performance on PICTs had a wider dietary breadth assayed using a free-choice task. Our results demonstrate that in systems or taxa where prior experience and differences in development cannot be accounted for, individual differences in performance on commonly used detour-dependent PICTS may reveal more about an individual's prior experience of transparent objects, or their motivation to acquire food, than providing a reliable measure of their inhibitory control. PMID:29593115

  2. A pilot investigation of acute inhibitory control training in cocaine users.

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    Alcorn, Joseph L; Pike, Erika; Stoops, William S; Lile, Joshua A; Rush, Craig R

    2017-05-01

    Disrupted response inhibition and presence of drug-cue attentional bias in cocaine-using individuals have predicted poor treatment outcomes. Inhibitory control training could help improve treatment outcomes by strengthening cognitive control. This pilot study assessed the effects of acute inhibitory control training to drug- and non-drug-related cues on response inhibition performance and cocaine-cue attentional bias in cocaine-using individuals. Participants who met criteria for a cocaine-use disorder underwent five sessions of inhibitory control training to either non-drug-related cues (i.e., rectangles) or cocaine cues (n=10/condition) in a single day. Response inhibition and attentional bias were assessed prior to and following training using the stop-signal task and visual-probe task with eye tracking, respectively. Training condition groups did not differ on demographics, inhibitory control training performance, response inhibition, or cocaine-cue attentional bias. Response inhibition performance improved as a function of inhibitory control training in both conditions. Cocaine-cue attentional bias was observed, but did not change as a function of inhibitory control training in either condition. Response inhibition in cocaine-using individuals was augmented by acute inhibitory control training, which may improve treatment outcomes through better behavioral inhibition. Future studies should investigate longer-term implementation of inhibitory control training, as well as combining inhibitory control training with other treatment modalities. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Residential Mobility, Inhibitory Control, and Academic Achievement in Preschool

    Science.gov (United States)

    Schmitt, Sara A.; Finders, Jennifer K.; McClelland, Megan M.

    2015-01-01

    Research Findings: The present study investigated the direct effects of residential mobility on children's inhibitory control and academic achievement during the preschool year. It also explored fall inhibitory control and academic skills as mediators linking residential mobility and spring achievement. Participants included 359 preschool children…

  4. Time Course of Brain Network Reconfiguration Supporting Inhibitory Control.

    Science.gov (United States)

    Popov, Tzvetan; Westner, Britta U; Silton, Rebecca L; Sass, Sarah M; Spielberg, Jeffrey M; Rockstroh, Brigitte; Heller, Wendy; Miller, Gregory A

    2018-05-02

    Hemodynamic research has recently clarified key nodes and links in brain networks implementing inhibitory control. Although fMRI methods are optimized for identifying the structure of brain networks, the relatively slow temporal course of fMRI limits the ability to characterize network operation. The latter is crucial for developing a mechanistic understanding of how brain networks shift dynamically to support inhibitory control. To address this critical gap, we applied spectrally resolved Granger causality (GC) and random forest machine learning tools to human EEG data in two large samples of adults (test sample n = 96, replication sample n = 237, total N = 333, both sexes) who performed a color-word Stroop task. Time-frequency analysis confirmed that recruitment of inhibitory control accompanied by slower behavioral responses was related to changes in theta and alpha/beta power. GC analyses revealed directionally asymmetric exchanges within frontal and between frontal and parietal brain areas: top-down influence of superior frontal gyrus (SFG) over both dorsal ACC (dACC) and inferior frontal gyrus (IFG), dACC control over middle frontal gyrus (MFG), and frontal-parietal exchanges (IFG, precuneus, MFG). Predictive analytics confirmed a combination of behavioral and brain-derived variables as the best set of predictors of inhibitory control demands, with SFG theta bearing higher classification importance than dACC theta and posterior beta tracking the onset of behavioral response. The present results provide mechanistic insight into the biological implementation of a psychological phenomenon: inhibitory control is implemented by dynamic routing processes during which the target response is upregulated via theta-mediated effective connectivity within key PFC nodes and via beta-mediated motor preparation. SIGNIFICANCE STATEMENT Hemodynamic neuroimaging research has recently clarified regional structures in brain networks supporting inhibitory control. However, due to

  5. Inhibitory control in childhood stuttering

    NARCIS (Netherlands)

    Eggers, K.; de Nil, L.; Van den Bergh, B.R.H.

    2013-01-01

    Purpose The purpose of this study was to investigate whether previously reported parental questionnaire-based differences in inhibitory control (IC; Eggers, De Nil, & Van den Bergh, 2010) would be supported by direct measurement of IC using a computer task. Method Participants were 30 children who

  6. Hunger, inhibitory control and distress-induced emotional eating.

    Science.gov (United States)

    van Strien, Tatjana; Ouwens, Machteld A; Engel, Carmen; de Weerth, Carolina

    2014-08-01

    Self-reported emotional eating has been found to significantly moderate distress-induced food intake, with low emotional eaters eating less after a stress task than after a control task and high emotional eaters eating more. The aim of the present study was to explore possible underlying mechanisms by assessing possible associations with (1) ability to experience the typical post-stress reduction of hunger and (2) inhibitory control. We studied these effects in 54 female students who were preselected on the basis of extremely high or low scores on an emotional eating questionnaire. Using a within subject design we measured the difference of actual food or snack intake after a control or a stress task (Trier Social Stress Test). As expected, the moderator effect of emotional eating on distress-induced food intake was found to be only present in females with a failure to report the typical reduction of hunger immediately after a stress task (an a-typical hunger stress response). Contrary to our expectations, this moderator effect of emotional eating was also found to be only present in females with high ability to stop motor impulses (high inhibitory control). These findings suggest that an a-typical hunger stress response but not poor inhibitory control may underlie the moderator effect of emotional eating on distress-induced food intake. However, inhibitory control may play a role whether or not there is a moderator effect of self-reported emotional eating on distress-induced food intake. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Performa Inhibitory Control dengan Induksi Sing-a-Song Stress Test pada Dewasa Awal

    Directory of Open Access Journals (Sweden)

    Akhmad Kurniawan

    2018-04-01

    Full Text Available Inhibitory control is able to control attention by inhibiting internal tendencies and external influences. Inhibitory control is controlled by dorsolateral prefrontal cortex and anterior cingulate cortex, that can be affected by stress variable. Sing-a-Song Stress Test (SSST is a current method to induce stress that has never been practiced in study of inhibitory control. This study aimed to determine the effect of SSST against inhibitory control in early adult. Between subjects design was applied in this study. A number of 35 participants with age range from 17 to 21 years old were randomly assigned into experimental group (n = 17 and control group (n = 18. Inhibitory control was measured using Computerized Stroop Color-Word Test (CSCWT. Positive Affect and Negative Affect Schedule (PANAS was used to conduct a manipulation check. Independent-Samples T Test explained no significant effect of stress on inhibitory control (t = -0,117; p > 0,05.

  8. Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality

    Directory of Open Access Journals (Sweden)

    Toria Herd

    2018-02-01

    Full Text Available Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems and social competence. In this prospective longitudinal study, we examine whether changes in inhibitory control, measured at both behavioral and neural levels, mediate the association between stress and changes in secure relationship quality with parents and peers. The sample included 167 adolescents (53% males who were first recruited at age 13 or 14 years and assessed annually three times. Adolescents’ inhibitory control was measured by their behavioral performance and brain activities, and adolescents self-reported perceived stress levels and relationship quality with mothers, fathers, and peers. Results suggest that behavioral inhibitory control mediates the association between perceived stress and adolescent’s secure relationship quality with their mothers and fathers, but not their peers. In contrast, given that stress was not significantly correlated with neural inhibitory control, we did not further test the mediation path. Our results highlight the role of inhibitory control as a process through which stressful life experiences are related to impaired secure relationship quality between adolescents and their mothers and fathers.

  9. Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality.

    Science.gov (United States)

    Herd, Toria; Li, Mengjiao; Maciejewski, Dominique; Lee, Jacob; Deater-Deckard, Kirby; King-Casas, Brooks; Kim-Spoon, Jungmeen

    2018-01-01

    Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems and social competence. In this prospective longitudinal study, we examine whether changes in inhibitory control, measured at both behavioral and neural levels, mediate the association between stress and changes in secure relationship quality with parents and peers. The sample included 167 adolescents (53% males) who were first recruited at age 13 or 14 years and assessed annually three times. Adolescents' inhibitory control was measured by their behavioral performance and brain activities, and adolescents self-reported perceived stress levels and relationship quality with mothers, fathers, and peers. Results suggest that behavioral inhibitory control mediates the association between perceived stress and adolescent's secure relationship quality with their mothers and fathers, but not their peers. In contrast, given that stress was not significantly correlated with neural inhibitory control, we did not further test the mediation path. Our results highlight the role of inhibitory control as a process through which stressful life experiences are related to impaired secure relationship quality between adolescents and their mothers and fathers.

  10. Attenuation of Experimental Pain by Vibro-Tactile Stimulation in Patients with Chronic Local or Widespread Musculoskeletal Pain

    OpenAIRE

    Staud, Roland; Robinson, Michael E.; Goldman, Casey T.; Price, Donald D.

    2011-01-01

    Patients with chronic pain syndromes, like fibromyalgia (FM) complain of widespread pain and tenderness, as well as non-refreshing sleep, cognitive dysfunction, and negative mood. Several lines of evidence implicate abnormalities of central pain processing as contributors for chronic pain, including dysfunctional descending pain inhibition. One form of endogenous pain inhibition, diffuse noxious inhibitory controls (DNIC), has been found to be abnormal in some chronic pain patients and eviden...

  11. Dogs' reaction to inequity is affected by inhibitory control.

    Science.gov (United States)

    Brucks, Désirée; Range, Friederike; Marshall-Pescini, Sarah

    2017-11-17

    Inequity aversion is thought to act as a mechanism to ensure cooperation and has been studied in many different species, consistently revealing inter-individual variation. Inhibitory control has been proposed to act as one factor responsible for this variation since individuals need to inhibit performing the required action and/or refuse rewards in order to exhibit inequity aversion. Here, we investigated if dogs' sensitivity to inequity is affected by their capacity for inhibitory control, assessed in a test battery and questionnaire. Overall, dogs showing high compulsivity scores (i.e. repetitive behaviours independent of feedback) were more motivated to participate in the inequity task independent of the rewarding scheme. Dogs were more sensitive to inequity and individual contrast if they exhibited a slower decision speed in the inhibition tasks. Furthermore, less persistent and more impulsive dogs were more sensitive to reward inequity, potentially due to having a lower tolerance level for frustration. Results indicate that aspects of inhibitory control can explain the variation in dogs' inequity response, highlighting one of the mechanisms underlying responses to inequity. Emphasising the importance to design paradigms, which allow us to disentangle capacities to recognise inequity from the inability to react to it due to poor inhibitory control abilities.

  12. The Effect of Domestication on Inhibitory Control: Wolves and Dogs Compared

    Science.gov (United States)

    Marshall-Pescini, Sarah; Virányi, Zsófia; Range, Friederike

    2015-01-01

    Inhibitory control i.e. blocking an impulsive or prepotent response in favour of a more appropriate alternative, has been suggested to play an important role in cooperative behaviour. Interestingly, while dogs and wolves show a similar social organization, they differ in their intraspecific cooperation tendencies in that wolves rely more heavily on group coordination in regard to hunting and pup-rearing compared to dogs. Hence, based on the ‘canine cooperation’ hypothesis wolves should show better inhibitory control than dogs. On the other hand, through the domestication process, dogs may have been selected for cooperative tendencies towards humans and/or a less reactive temperament, which may in turn have affected their inhibitory control abilities. Hence, based on the latter hypothesis, we would expect dogs to show a higher performance in tasks requiring inhibitory control. To test the predictive value of these alternative hypotheses, in the current study two tasks; the ‘cylinder task’ and the ‘detour task’, which are designed to assess inhibitory control, were used to evaluate the performance of identically raised pack dogs and wolves. Results from the cylinder task showed a significantly poorer performance in wolves than identically-raised pack dogs (and showed that pack-dogs performed similarly to pet dogs with different training experiences), however contrary results emerged in the detour task, with wolves showing a shorter latency to success and less perseverative behaviour at the fence. Results are discussed in relation to previous studies using these paradigms and in terms of the validity of these two methods in assessing inhibitory control. PMID:25714840

  13. Distinguishing between impairments of working memory and inhibitory control in cases of early dementia.

    Science.gov (United States)

    Crawford, Trevor J; Higham, Steve

    2016-01-29

    Dementia (most notably, Alzheimer's Disease) is often associated with impairments of both working memory and inhibitory control. However, it is unclear whether these are functionally distinct impairments. We addressed the issue of whether working memory and inhibitory control can be dissociated, using data from a sample of patients who were recruited in a longitudinal study (Crawford et al., 2013, 2015). The first case revealed a preserved working memory capacity together with poor inhibitory control in the anti-saccade task. A longitudinal follow-up revealed that the defective inhibitory control emerged 12-months before the dementia was evident on the mini-mental state examination assessment. A second case revealed a poor working memory together with a well-preserved level of inhibitory control. The dissociation of working memory and inhibitory control was confirmed statistically in 7 additional cases. These findings yield converging evidence that working memory and inhibitory control are distinct cognitive operations and challenges the Kimberg and Farah (2000) cognitive model of working memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Inhibitory control and moral emotions: relations to reparation in early and middle childhood.

    Science.gov (United States)

    Colasante, Tyler; Zuffianò, Antonio; Bae, Na Young; Malti, Tina

    2014-01-01

    This study examined links between inhibitory control, moral emotions (sympathy and guilt), and reparative behavior in an ethnically diverse sample of 4- and 8-year-olds (N = 162). Caregivers reported their children's reparative behavior, inhibitory control, and moral emotions through a questionnaire, and children reported their guilt feelings in response to a series of vignettes depicting moral transgressions. A hypothesized meditation model was tested with inhibitory control relating to reparative behavior through sympathy and guilt. In support of this model, results revealed that high levels of inhibitory control were associated with high levels of reparative behavior through high levels of sympathy and guilt. However, the mediation of inhibitory control to reparation through guilt was significant for 4-year-olds only. Results are discussed in relation to the temperamental, regulatory, and affective-moral precursors of reparative behavior in early and middle childhood.

  15. Determinants of aggressive behavior: Interactive effects of emotional regulation and inhibitory control.

    Directory of Open Access Journals (Sweden)

    I-Ju Hsieh

    Full Text Available Aggressive behavior can be defined as any behavior intended to hurt another person, and it is associated with many individual and social factors. This study examined the relationship between emotional regulation and inhibitory control in predicting aggressive behavior. Seventy-eight participants (40 males completed self-report measures (Negative Mood Regulation Scale and Buss-Perry Aggression Questionnaire, a stop signal task, and engaged in a modified version of Taylor Aggression Paradigm (TAP exercise, in which the outcome was used as a measure of direct physical aggression. We used a hierarchical, mixed-model multiple regression analysis test to examine the effects of emotion regulation and inhibitory control on physical reactive aggression. Results indicated an interaction between emotion regulation and inhibitory control on aggression. For participants with low inhibitory control only, there was a significant difference between high and low emotion regulation on aggression, such that low emotion regulation participants registered higher aggression than high emotion regulation participants. This difference was not found among participants with high inhibitory control. These results have implications for refining and targeting training and rehabilitation programs aimed at reducing aggressive behavior.

  16. Sex Differences in How Erotic and Painful Stimuli Impair Inhibitory Control

    Science.gov (United States)

    Yu, Jiaxin; Hung, Daisy L.; Tseng, Philip; Tzeng, Ovid J. L.; Muggleton, Neil G.; Juan, Chi-Hung

    2012-01-01

    Witnessing emotional events such as arousal or pain may impair ongoing cognitive processes such as inhibitory control. We found that this may be true only half of the time. Erotic images and painful video clips were shown to men and women shortly before a stop signal task, which measures cognitive inhibitory control. These stimuli impaired…

  17. Inhibitory control and negative emotional processing in psychopathy and antisocial personality disorder.

    Science.gov (United States)

    Verona, Edelyn; Sprague, Jenessa; Sadeh, Naomi

    2012-05-01

    The field of personality disorders has had a long-standing interest in understanding interactions between emotion and inhibitory control, as well as neurophysiological indices of these processes. More work in particular is needed to clarify differential deficits in offenders with antisocial personality disorder (APD) who differ on psychopathic traits, as APD and psychopathy are considered separate, albeit related, syndromes. Evidence of distinct neurobiological processing in these disorders would have implications for etiology-based personality disorder taxonomies in future psychiatric classification systems. To inform this area of research, we recorded event-related brain potentials during an emotional-linguistic Go/No-Go task to examine modulation of negative emotional processing by inhibitory control in three groups: psychopathy (n = 14), APD (n = 16), and control (n = 15). In control offenders, inhibitory control demands (No-Go vs. Go) modulated frontal-P3 amplitude to negative emotional words, indicating appropriate prioritization of inhibition over emotional processing. In contrast, the psychopathic group showed blunted processing of negative emotional words regardless of inhibitory control demands, consistent with research on emotional deficits in psychopathy. Finally, the APD group demonstrated enhanced processing of negative emotion words in both Go and No-Go trials, suggesting a failure to modulate negative emotional processing when inhibitory control is required. Implications for emotion-cognition interactions and putative etiological processes in these personality disorders are discussed.

  18. Inhibitory Control in Speech Comprehension among Dai–Han Bilingual Children

    Directory of Open Access Journals (Sweden)

    Yun Tao

    2017-08-01

    Full Text Available We aimed to investigate differences in inhibitory control ability between proficient and non-proficient Dai–Han bilinguals. Two experiments used a combined stimulus–stimulus and stimulus–response compatibility paradigm for this purpose. Participants were Dai–Han bilingual primary-school students selected from a Dai-speaking town in Yunnan province, China. In Dai language interference condition, participants were asked to complete a picture category task. Results showed that the effect of attentional control for non-proficient bilinguals (NPBs was significantly greater than that for proficient bilinguals (PBs, while the effect of response inhibition was not. This implied that a difference in inhibitory control between PBs and NPBs appeared at the attention control stage when interference by the Dai lexicon emerged. In Han language interference condition, however, participants were also asked to complete the same task. Results showed that the effect of response inhibition for NPBs was significantly greater than that for PBs, but the effect of attentional control was not. This demonstrated that a difference in inhibitory control emerged at the response inhibition stage when interference by the Han lexicon emerged. This pattern of results is opposite to previous researches, which indicated that the difference between PBs and NPBs occurred at the response inhibition stage under first language condition, whereas at the attentional control stage under second language (L2 condition. Based on these, this study suggests that Dai–Han bilinguals showed a remarkable L2 advantage. In addition, results showed that response times (RTs of PBs were faster than RTs of NPBs while confounding variables (e.g., intelligence, etc. were under control. This indicates that the inhibitory control ability of the PBs is superior to that of NPBs in this study.

  19. Neuroscientific Insights: Attention, Working Memory, and Inhibitory Control

    Science.gov (United States)

    Raver, C. Cybele; Blair, Clancy

    2016-01-01

    In this article, Cybele Raver and Clancy Blair explore a group of cognitive processes called executive function (EF)--including the flexible control of attention, the ability to hold information through working memory, and the ability to maintain inhibitory control. EF processes are crucial for young children's learning. On the one hand, they can…

  20. The role of cardiac vagal tone and inhibitory control in pre-schoolers' listening comprehension.

    Science.gov (United States)

    Scrimin, Sara; Patron, Elisabetta; Florit, Elena; Palomba, Daniela; Mason, Lucia

    2017-12-01

    This study investigated the role of basal cardiac activity and inhibitory control at the beginning of the school year in predicting oral comprehension at the end of the year in pre-schoolers. Forty-three, 4-year-olds participated in the study. At the beginning of the school year children's electrocardiogram at rest was registered followed by the assessment of inhibitory control as well as verbal working memory and verbal ability. At the end of the year all children were administered a listening comprehension ability measure. A stepwise regression showed a significant effect of basal cardiac vagal tone in predicting listening comprehension together with inhibitory control and verbal ability. These results are among the first to show the predictive role of basal cardiac vagal tone and inhibitory control in pre-schoolers' oral text comprehension, and offer new insight into the association between autonomic regulation of the heart, inhibitory control, and cognitive activity at a young age. © 2017 Wiley Periodicals, Inc.

  1. Investigating Inhibitory Control in Children with Epilepsy: An fMRI Study

    Science.gov (United States)

    Triplett, Regina L.; Velanova, Katerina; Luna, Beatriz; Padmanabhan, Aarthi; Gaillard, William D.; Asato, Miya R.

    2014-01-01

    SUMMARY Objective Deficits in executive function are increasingly noted in children with epilepsy and have been associated with poor academic and psychosocial outcomes. Impaired inhibitory control contributes to executive dysfunction in children with epilepsy; however, its neuroanatomic basis has not yet been investigated. We used functional Magnetic Resonance Imaging (fMRI) to probe the integrity of activation in brain regions underlying inhibitory control in children with epilepsy. Methods This cross-sectional study consisted of 34 children aged 8 to 17 years: 17 with well-controlled epilepsy and 17 age-and sex-matched controls. Participants performed the antisaccade (AS) task, representative of inhibitory control, during fMRI scanning. We compared AS performance during neutral and reward task conditions and evaluated task-related blood-oxygen level dependent (BOLD) activation. Results Children with epilepsy demonstrated impaired AS performance compared to controls during both neutral (non-reward) and reward trials, but exhibited significant task improvement during reward trials. Post-hoc analysis revealed that younger patients made more errors than older patients and all controls. fMRI results showed preserved activation in task-relevant regions in patients and controls, with the exception of increased activation in the left posterior cingulate gyrus in patients specifically with generalized epilepsy across neutral and reward trials. Significance Despite impaired inhibitory control, children with epilepsy accessed typical neural pathways as did their peers without epilepsy. Children with epilepsy showed improved behavioral performance in response to the reward condition, suggesting potential benefits of the use of incentives in cognitive remediation. PMID:25223606

  2. Polynuclear water-soluble dinitrosyl iron complexes with cysteine or glutathione ligands: electron paramagnetic resonance and optical studies.

    Science.gov (United States)

    Vanin, Anatoly F; Poltorakov, Alexander P; Mikoyan, Vasak D; Kubrina, Lyudmila N; Burbaev, Dosymzhan S

    2010-09-15

    Electron paramagnetic resonance and optical spectrophotometric studies have demonstrated that low-molecular dinitrosyl iron complexes (DNICs) with cysteine or glutathione exist in aqueous solutions in the form of paramagnetic mononuclear (capital EM, Cyrillic-DNICs) and diamagnetic binuclear complexes (B-DNICs). The latter represent Roussin's red salt esters and can be prepared by treatment of aqueous solutions of Fe(2+) and thiols (small er, Cyrilliccapital EN, Cyrillic 7.4) with gaseous nitric oxide (NO) at the thiol:Fe(2+) ratio 1:1. capital EM, Cyrillic-DNICs are synthesized under identical conditions at the thiol:Fe(2+) ratios above 20 and produce an EPR signal with an electronic configuration {Fe(NO)(2)}(7) at g(aver.)=2.03. At neutral pH, aqueous solutions contain both M-DNICs and B-DNICs (the content of the latter makes up to 50% of the total DNIC pool). The concentration of B-DNICs decreases with a rise in pH; at small er, Cyrilliccapital EN, Cyrillic 9-10, the solutions contain predominantly M-DNICs. The addition of thiol excess to aqueous solutions of B-DNICs synthesized at the thiol:Fe(2+) ratio 1:2 results in their conversion into capital EM, Cyrillic-DNICs, the total amount of iron incorporated into M-DNICs not exceeding 50% of the total iron pool in B-DNICs. Air bubbling of cys-capital EM, Cyrillic-DNIC solutions results in cysteine oxidation-controlled conversion of capital EM, Cyrillic-DNICs first into cys-B-DNICs and then into the EPR-silent compound capital HA, Cyrillic able to generate a strong absorption band at 278 nm. In the presence of glutathione or cysteine excess, compound capital HA, Cyrillic is converted into B-DNIC/M-DNIC and is completely decomposed under effect of the Fe(2+) chelator small o, Cyrillic-phenanthroline or N-methyl-d-glucamine dithiocarbamate (MGD). Moreover, MGD initiates the synthesis of paramagnetic mononitrosyl iron complexes with MGD. It is hypothesized that compound capital HA, Cyrillic represents a polynuclear

  3. Inhibitory control is not lateralized in Parkinson's patients.

    Science.gov (United States)

    Mirabella, G; Fragola, M; Giannini, G; Modugno, N; Lakens, Daniel

    2017-07-28

    Parkinson's disease (PD) is often characterized by asymmetrical symptoms, which are more prominent on the side of the body contralateral to the most extensively affected brain hemisphere. Therefore, lateralized PD presents an opportunity to examine the effects of asymmetric subcortical dopamine deficiencies on cognitive functioning. As it has been hypothesized that inhibitory control relies upon a right-lateralized pathway, we tested whether left-dominant PD (LPD) patients suffered from a more severe deficit in this key executive function than right-dominant PD patients (RPD). To this end, via a countermanding task, we assessed both proactive and reactive inhibition in 20 LPD and 20 RPD patients, and in 20 age-matched healthy subjects. As expected, we found that PD patients were significantly more impaired in both forms of inhibitory control than healthy subjects. However, there were no differences either in reactive or proactive inhibition between LPD and RPD patients. All in all, these data support the idea that brain regions affected by PD play a fundamental role in subserving inhibitory function, but do not sustain the hypothesis according to which this executive function is predominantly or solely computed by the brain regions of the right hemisphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality

    OpenAIRE

    Toria Herd; Mengjiao Li; Dominique Maciejewski; Jacob Lee; Kirby Deater-Deckard; Brooks King-Casas; Jungmeen Kim-Spoon

    2018-01-01

    Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems...

  5. Can Working Memory and Inhibitory Control Predict Second Language Learning in the Classroom?

    Directory of Open Access Journals (Sweden)

    Jared A. Linck

    2015-10-01

    Full Text Available The role of executive functioning in second language (L2 aptitude remains unclear. Whereas some studies report a relationship between working memory (WM and L2 learning, others have argued against this association. Similarly, being bilingual appears to benefit inhibitory control, and individual differences in inhibitory control are related to online L2 processing. The current longitudinal study examines whether these two components of executive functioning predict learning gains in an L2 classroom context using a pretest/posttest design. We assessed 25 university students in language courses, who completed measures of WM and inhibitory control. They also completed a proficiency measure at the beginning and end of a semester and reported their grade point average (GPA. WM was positively related to L2 proficiency and learning, but inhibitory control was not. These results support the notion that WM is an important component of L2 aptitude, particularly for predicting the early stages of L2 classroom learning.

  6. Inhibitory control in young children and its role in emerging internalization.

    Science.gov (United States)

    Kochanska, G; Murray, K; Jacques, T Y; Koenig, A L; Vandegeest, K A

    1996-04-01

    We examined inhibitory control as a quality of temperament that contributes to internalization. Children were assessed twice, at 26-41 months (N = 103) and at 43-56 months (N = 99), on repeated occasions, in multiple observational contexts and using parental reports. Comprehensive behavioral batteries incorporating multiple tasks were designed to measure inhibitory control at toddler and preschool age. They had good internal consistencies, corresponded with maternal ratings, and were developmentally sensitive. Individual children's performance was significantly correlated across both assessments, indicating stable individual differences. Girls surpassed boys at both ages. Children's internalization was observed while they were alone with prohibited objects, with a mundane chore, playing games that occasioned cheating, being induced to violate standards of conduct, and assessed using maternal reports. Inhibitory control was significantly associated with internalization, both contemporaneously and as a predictor in the longitudinal sense. The implications for considering children's temperament as a significant, yet often neglected contributor to developing internalization are discussed.

  7. Rational Decision-Making in Inhibitory Control

    Science.gov (United States)

    Shenoy, Pradeep; Yu, Angela J.

    2011-01-01

    An important aspect of cognitive flexibility is inhibitory control, the ability to dynamically modify or cancel planned actions in response to changes in the sensory environment or task demands. We formulate a probabilistic, rational decision-making framework for inhibitory control in the stop signal paradigm. Our model posits that subjects maintain a Bayes-optimal, continually updated representation of sensory inputs, and repeatedly assess the relative value of stopping and going on a fine temporal scale, in order to make an optimal decision on when and whether to go on each trial. We further posit that they implement this continual evaluation with respect to a global objective function capturing the various reward and penalties associated with different behavioral outcomes, such as speed and accuracy, or the relative costs of stop errors and go errors. We demonstrate that our rational decision-making model naturally gives rise to basic behavioral characteristics consistently observed for this paradigm, as well as more subtle effects due to contextual factors such as reward contingencies or motivational factors. Furthermore, we show that the classical race model can be seen as a computationally simpler, perhaps neurally plausible, approximation to optimal decision-making. This conceptual link allows us to predict how the parameters of the race model, such as the stopping latency, should change with task parameters and individual experiences/ability. PMID:21647306

  8. Rational decision-making in inhibitory control.

    Science.gov (United States)

    Shenoy, Pradeep; Yu, Angela J

    2011-01-01

    An important aspect of cognitive flexibility is inhibitory control, the ability to dynamically modify or cancel planned actions in response to changes in the sensory environment or task demands. We formulate a probabilistic, rational decision-making framework for inhibitory control in the stop signal paradigm. Our model posits that subjects maintain a Bayes-optimal, continually updated representation of sensory inputs, and repeatedly assess the relative value of stopping and going on a fine temporal scale, in order to make an optimal decision on when and whether to go on each trial. We further posit that they implement this continual evaluation with respect to a global objective function capturing the various reward and penalties associated with different behavioral outcomes, such as speed and accuracy, or the relative costs of stop errors and go errors. We demonstrate that our rational decision-making model naturally gives rise to basic behavioral characteristics consistently observed for this paradigm, as well as more subtle effects due to contextual factors such as reward contingencies or motivational factors. Furthermore, we show that the classical race model can be seen as a computationally simpler, perhaps neurally plausible, approximation to optimal decision-making. This conceptual link allows us to predict how the parameters of the race model, such as the stopping latency, should change with task parameters and individual experiences/ability.

  9. Differences in Inhibitory Control between Impulsive and Premeditated Aggression in Juvenile Inmates

    Directory of Open Access Journals (Sweden)

    Zhuo Zhang

    2017-07-01

    Full Text Available Inhibitory control dysfunction was considered a universal characteristic of violent offenders. The aim of this study was to examine differences in inhibitory control between two subtypes of violent youth; those displaying predominantly impulsive and those presenting predominantly premeditated aggression (PM. Forty-four juvenile offenders, defined on the basis of the Procedures for the Classification of Aggressive/Violent Acts (Stanford and Barratt, 2001 participated (N = 23: impulsive; N = 21 premeditated. A visual Go/NoGo task was used to compare behavioral responses and event-related potentials (ERPs between groups. The task contained two letters (W and M, W was the Go stimulus and M the NoGo stimulus. The impulsive youth showed a significantly greater decrease in N2 latency for Go relative to NoGo trials than the premeditated aggressive youth. The differentiation in N2 amplitude between Go and NoGo (N2d was negatively correlated with impulsivity of aggression. Both groups showed no significant central NoGo P3. Our findings suggest that impulsive violent youth show stronger prepotent responses and impaired conflict monitoring during early inhibitory control processing relative to premeditated aggressive youth. Both impulsive and premeditated violent youth may show impaired response inhibition at the late processing stage of inhibitory control.

  10. Effects of incentives, age, and behavior on brain activation during inhibitory control: A longitudinal fMRI study

    Directory of Open Access Journals (Sweden)

    David J. Paulsen

    2015-02-01

    Full Text Available We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.

  11. Conflict Inhibitory Control Facilitates Pretense Quality in Young Preschoolers

    Science.gov (United States)

    Van Reet, Jennifer

    2015-01-01

    The present research explores the role of inhibitory control (IC) in young preschoolers' pretense ability using an ego depletion paradigm. In Experiment 1 (N = 56), children's pretense ability was assessed either before or after participating in conflict IC or control tasks, and in Experiment 2 (N = 36), pretense ability was measured after…

  12. Early adversity, RSA, and inhibitory control: evidence of children's neurobiological sensitivity to social context.

    Science.gov (United States)

    Skowron, Elizabeth A; Cipriano-Essel, Elizabeth; Gatzke-Kopp, Lisa M; Teti, Douglas M; Ammerman, Robert T

    2014-07-01

    This study examined parasympathetic physiology as a moderator of the effects of early adversity (i.e., child abuse and neglect) on children's inhibitory control. Children's respiratory sinus arrhythmia (RSA) was assessed during a resting baseline, two joint challenge tasks with mother, and an individual frustration task. RSA assessed during each of the joint parent-child challenge tasks moderated the effects of child maltreatment (CM) status on children's independently-assessed inhibitory control. No moderation effect was found for RSA assessed at baseline or in the child-alone challenge task. Among CM-exposed children, lower RSA levels during the joint task predicted the lowest inhibitory control, whereas higher joint task RSA was linked to higher inhibitory control scores that were indistinguishable from those of non-CM children. Results are discussed with regard to the importance of considering context specificity (i.e., individual and caregiver contexts) in how biomarkers inform our understanding of individual differences in vulnerability among at-risk children. © 2013 Wiley Periodicals, Inc.

  13. Controlled versus automatic processes: which is dominant to safety? The moderating effect of inhibitory control.

    Directory of Open Access Journals (Sweden)

    Yaoshan Xu

    Full Text Available This study explores the precursors of employees' safety behaviors based on a dual-process model, which suggests that human behaviors are determined by both controlled and automatic cognitive processes. Employees' responses to a self-reported survey on safety attitudes capture their controlled cognitive process, while the automatic association concerning safety measured by an Implicit Association Test (IAT reflects employees' automatic cognitive processes about safety. In addition, this study investigates the moderating effects of inhibition on the relationship between self-reported safety attitude and safety behavior, and that between automatic associations towards safety and safety behavior. The results suggest significant main effects of self-reported safety attitude and automatic association on safety behaviors. Further, the interaction between self-reported safety attitude and inhibition and that between automatic association and inhibition each predict unique variances in safety behavior. Specifically, the safety behaviors of employees with lower level of inhibitory control are influenced more by automatic association, whereas those of employees with higher level of inhibitory control are guided more by self-reported safety attitudes. These results suggest that safety behavior is the joint outcome of both controlled and automatic cognitive processes, and the relative importance of these cognitive processes depends on employees' individual differences in inhibitory control. The implications of these findings for theoretical and practical issues are discussed at the end.

  14. Reward, interrupted: Inhibitory control and its relevance to addictions.

    Science.gov (United States)

    Jentsch, James David; Pennington, Zachary T

    2014-01-01

    There are broad individual differences in the ability to voluntarily and effortfully suppress motivated, reward-seeking behaviors, and this review presents the hypothesis that these individual differences are relevant to addictive disorders. On one hand, cumulative experience with drug abuse appears to alter the molecular, cellular and circuit mechanisms that mediate inhibitory abilities, leading to increasingly uncontrolled patterns of drug-seeking and -taking. On the other, native inter-individual differences in inhibitory control are apparently a risk factor for aspects of drug-reinforced responding and substance use disorders. In both cases, the behavioral manifestation of poor inhibitory abilities is linked to relatively low striatal dopamine D2-like receptor availability, and evidence is accumulating for a more direct contribution of striatopallidal neurons to cognitive control processes. Mechanistic research is now identifying genes upstream of dopamine transmission that mediate these relationships, as well as the involvement of other neurotransmitter systems, acting alone and in concert with dopamine. The reviewed research stands poised to identify new mechanisms that can be targeted by pharmacotherapies and/or by behavioral interventions that are designed to prevent or treat addictive behaviors and associated behavioral pathology. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A cross-cultural investigation of inhibitory control, generative fluency, and anxiety symptoms in Romanian and Russian preschoolers.

    Science.gov (United States)

    Cheie, Lavinia; Veraksa, Aleksander; Zinchenko, Yuri; Gorovaya, Alexandra; Visu-Petra, Laura

    2015-01-01

    The current study focused on the early development of inhibitory control in 5- to 7-year-old children attending kindergarten in two Eastern-European countries, Romania and Russia. These two countries share many aspects of child-rearing and educational practices, previously documented to influence the development of inhibitory control. Using the Lurian-based developmental approach offered by the Developmental Neuropsychological Assessment battery, the study aimed to contribute to cross-cultural developmental neuropsychology by exploring (a) early interrelationships between subcomponents of inhibitory control (response suppression and attention control) and generative fluency (verbal and figural) in these two cultures, as well as (b) the predictive value of external factors (culture and maternal education) and individual differences (age, gender, nonverbal intelligence, trait anxiety) on inhibitory control and fluency outcomes in children from both countries. First, findings in both culture samples suggest that even at this young age, the construct of inhibitory control cannot be considered a unitary entity. Second, differences in maternal education were not predictive of either inhibitory control or fluency scores. However, children's attention control performance varied as a function of culture, and the direction of these cultural effects differed by whether the target outcome involved performance accuracy versus efficiency as an output. Findings also confirmed the previously documented intensive developmental improvement in preschoolers' inhibitory control during this period, influencing measures of response suppression and particularly attention control. Finally, the results further stress the importance of individual differences effects in trait anxiety on attention control efficiency across cultures.

  16. Altruistic sharing behavior in children: Role of theory of mind and inhibitory control.

    Science.gov (United States)

    Liu, Buyun; Huang, Zhelan; Xu, Guifeng; Jin, Yu; Chen, Yajun; Li, Xiuhong; Wang, Qingxiong; Song, Shanshan; Jing, Jin

    2016-01-01

    This study aimed to assess altruistic sharing behavior in children aged 3 to 5, 6 to 8, and 9 to 11 years and to explore the involvement of potential cognitive mechanisms, namely theory of mind (ToM) and inhibitory control. A total of 158 children completed a dictator game with stickers as incentives. ToM was evaluated using a false belief task in preschoolers and the Strange Story Test in school-age children. Inhibitory control was assessed in preschoolers with the Day-Night task and in older children with the Stroop Color-Word Test. The result was that 48.10% of children aged 3 to 5 years decided to share, and the percentage rose significantly with increasing age. The difference in altruism level in children who decided to share among the three age groups was nonsignificant. These results suggest that mechanisms underlying the decision to share or not and altruistic behavior may be different. No significant linear relations were found between cognitive processes (i.e., ToM and inhibitory control) and sharing behavior. Surprisingly, 9- to 11-year-olds who shared 3 of 10 stickers performed worse in inhibitory control than did those who shared any other number of stickers. In conclusion, the proportion of children who decided to share, but not the level of altruism, increased with age. ToM was not involved in altruistic sharing, whereas inhibitory control may play a role when deciding how much to share. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Specific alteration of rhythm in temperature-stressed rats possess features of abdominal pain in IBS patients

    Directory of Open Access Journals (Sweden)

    Yasuo Itomi

    2015-09-01

    Full Text Available It is known that specific alteration of rhythm in temperature (SART stress produces somatic pain. However, it remains to be investigated whether SART stress induces visceral pain. In this study, we investigated the visceral hypersensitivity in the SART stress model by pharmacological tools and heterotopical nociception. Four-week-old Sprague–Dawley rats were exposed to repeated cold stress. Visceral pain was measured by visceromotor response to colorectal distension, and the effects of alosetron and duloxetine on visceral pain were investigated in SART rats. Heterotopical nociception was given by capsaicin injection into the left forepaw to induce diffuse noxious inhibitory controls (DNIC. SART stress induced visceral hypersensitivity that was sustained at minimum for one week. In pharmacological analysis, alosetron and duloxetine improved SART stress-induced visceral hypersensitivity. Heterotopical nociception induced DNIC in normal conditions, but was disrupted in SART rats. On the other hand, RMCP-II mRNA in distal colon was not affected by SART stress. In conclusion, SART rats exhibit several features of visceral pain in IBS, and may be a useful model for investigating the central modification of pain control in IBS.

  18. High-disinhibition restrained eaters are disinhibited by self-regulatory depletion in the food-related inhibitory control.

    Science.gov (United States)

    Zhou, Yizhou; Gao, Xiao; Chen, Hong; Kong, Fanchang

    2017-08-01

    Restrained eating for weight control and loss is becoming highly prevalent in many affluent societies, while most of the restrained eaters are rather unsuccessful in the long term. According to the strength model of self-control, the disinhibition effect of restrained eaters may occur after the depletion of self-control resources. However, no work has examined the direct impact of self-control resources on inhibitory control ability of restrained eaters. This study investigated the influences of self-control resources on the food-related inhibitory control among high-restraint/low-disinhibition restrained eaters, high-restraint/high-disinhibition restrained eaters and unrestrained eaters using stop signal task. Results reveal that there's no difference of food-related inhibitory control between three groups when the self-control resources are non-depleted, while high-restraint/high-disinhibition restrained eaters showing a decrease of food-related inhibitory control after ego-depletion. This disinhibition effect only seems to occur in samples of restrained eaters with a high tendency toward overeating. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Early Adversity, RSA, and Inhibitory Control: Evidence of Children’s Neurobiological Sensitivity to Social Context

    Science.gov (United States)

    Skowron, Elizabeth A.; Cipriano-Essel, Elizabeth; Gatzke-Kopp, Lisa M.; Teti, Douglas M.; Ammerman, Robert T.

    2014-01-01

    This study examined parasympathetic physiology as a moderator of the effects of early adversity (i.e., child abuse and neglect) on children’s inhibitory control. Children’s respiratory sinus arrhythmia (RSA) was assessed during a resting baseline, two joint challenge tasks with mother, and an individual frustration task. RSA assessed during each of the joint parent–child challenge tasks moderated the effects of child maltreatment (CM) status on children’s independently-assessed inhibitory control. No moderation effect was found for RSA assessed at baseline or in the child-alone challenge task. Among CM-exposed children, lower RSA levels during the joint task predicted the lowest inhibitory control, whereas higher joint task RSA was linked to higher inhibitory control scores that were indistinguishable from those of non-CM children. Results are discussed with regard to the importance of considering context specificity (i.e., individual and caregiver contexts) in how biomarkers inform our understanding of individual differences in vulnerability among at-risk children. PMID:24142832

  20. Timing control by redundant inhibitory neuronal circuits

    International Nuclear Information System (INIS)

    Tristan, I.; Rulkov, N. F.; Huerta, R.; Rabinovich, M.

    2014-01-01

    Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model

  1. Timing control by redundant inhibitory neuronal circuits

    Energy Technology Data Exchange (ETDEWEB)

    Tristan, I., E-mail: itristan@ucsd.edu; Rulkov, N. F.; Huerta, R.; Rabinovich, M. [BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0402 (United States)

    2014-03-15

    Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model.

  2. Dissociable Fronto-Operculum-Insula Control Signals for Anticipation and Detection of Inhibitory Sensory Cue.

    Science.gov (United States)

    Cai, Weidong; Chen, Tianwen; Ide, Jaime S; Li, Chiang-Shan R; Menon, Vinod

    2017-08-01

    The ability to anticipate and detect behaviorally salient stimuli is important for virtually all adaptive behaviors, including inhibitory control that requires the withholding of prepotent responses when instructed by external cues. Although right fronto-operculum-insula (FOI), encompassing the anterior insular cortex (rAI) and inferior frontal cortex (rIFC), involvement in inhibitory control is well established, little is known about signaling mechanisms underlying their differential roles in detection and anticipation of salient inhibitory cues. Here we use 2 independent functional magnetic resonance imaging data sets to investigate dynamic causal interactions of the rAI and rIFC, with sensory cortex during detection and anticipation of inhibitory cues. Across 2 different experiments involving auditory and visual inhibitory cues, we demonstrate that primary sensory cortex has a stronger causal influence on rAI than on rIFC, suggesting a greater role for the rAI in detection of salient inhibitory cues. Crucially, a Bayesian prediction model of subjective trial-by-trial changes in inhibitory cue anticipation revealed that the strength of causal influences from rIFC to rAI increased significantly on trials in which participants had higher anticipation of inhibitory cues. Together, these results demonstrate the dissociable bottom-up and top-down roles of distinct FOI regions in detection and anticipation of behaviorally salient cues across multiple sensory modalities. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Effects of acute buspirone administration on inhibitory control and sexual discounting in cocaine users.

    Science.gov (United States)

    Strickland, Justin C; Bolin, B Levi; Romanelli, Michael R; Rush, Craig R; Stoops, William W

    2017-01-01

    Cocaine users display deficits in inhibitory control and make impulsive choices that may increase risky behavior. Buspirone is an anxiolytic that activates dopaminergic and serotonergic systems and improves impulsive choice (i.e., reduces sexual risk-taking intent) in cocaine users when administered chronically. We evaluated the effects of acutely administered buspirone on inhibitory control and impulsive choice. Eleven subjects with a recent history of cocaine use completed this within-subject, placebo-controlled study. Subjects performed two cued go/no-go and a sexual risk delay-discounting task following oral administration of buspirone (10 and 30 mg), triazolam (0.375 mg; positive control), and placebo (negative control). Physiological and psychomotor performance and subject-rated data were also collected. Buspirone failed to change inhibitory control or impulsive choice; however, slower reaction times were observed at the highest dose tested. Buspirone did not produce subject-rated drug effects but dose-dependently decreased diastolic blood pressure. Triazolam impaired psychomotor performance and increased ratings of positive subject-rated effects (e.g., Like Drug). These findings indicate that acutely administered buspirone has little impact on behavioral measures of inhibitory control and impulsive sexual decision-making. Considering previous findings with chronic dosing, these findings highlight that the behavioral effects of buspirone differ as a function of dosing conditions. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Inhibitory Control of Proactive Interference in Adults with ADHD

    Science.gov (United States)

    White, Holly A.

    2007-01-01

    Objective: Attention deficit hyperactivity disorder (ADHD) is associated with poor inhibition of prepotent responses and deficits in distractor inhibition, but relatively few studies have addressed inhibitory control of proactive interference (PI) in individuals with ADHD. Thus, the goal of the present study was to evaluate resistance to spatial…

  5. ANS acuity and mathematics ability in preschoolers from low-income homes: contributions of inhibitory control.

    Science.gov (United States)

    Fuhs, Mary Wagner; McNeil, Nicole M

    2013-01-01

    Recent findings by Libertus, Feigenson, and Halberda (2011) suggest that there is an association between the acuity of young children's approximate number system (ANS) and their mathematics ability before exposure to instruction in formal schooling. The present study examined the generalizability and validity of these findings in a sample of preschoolers from low-income homes. Children attending Head Start (N = 103) completed measures to assess ANS acuity, mathematics ability, receptive vocabulary, and inhibitory control. Results showed only a weak association between ANS acuity and mathematics ability that was reduced to non-significance when controlling for a direct measure of receptive vocabulary. Results also revealed that inhibitory control plays an important role in the relation between ANS acuity and mathematics ability. Specifically, ANS acuity accounted for significant variance in mathematics ability over and above receptive vocabulary, but only for ANS acuity trials in which surface area conflicted with numerosity. Moreover, this association became non-significant when controlling for inhibitory control. These results suggest that early mathematical experiences prior to formal schooling may influence the strength of the association between ANS acuity and mathematics ability and that inhibitory control may drive that association in young children. © 2012 Blackwell Publishing Ltd.

  6. Complete unconscious control: Using (in)action primes to demonstrate completely unconscious activation of inhibitory control mechanisms

    Science.gov (United States)

    Hepler, Justin; Albarracin, Dolores

    2018-01-01

    Although robust evidence indicates that action initiation can occur unconsciously and unintentionally, the literature on action inhibition suggests that inhibition requires both conscious thought and intentionality. In prior research demonstrating automatic inhibition in response to unconsciously processed stimuli, the unconscious stimuli had previously been consciously associated with an inhibitory response within the context of the experiment, and participants had consciously formed a goal to activate inhibition processes when presented with the stimuli (because task instructions required participants to engage in inhibition when the stimuli occurred). Therefore, prior work suggests that some amount of conscious thought and intentionality are required for inhibitory control. In the present research, we recorded event-related potentials during two go/no-go experiments in which participants were subliminally primed with general action/inaction concepts that had never been consciously associated with task-specific responses. We provide the first demonstration that inhibitory control processes can be modulated completely unconsciously and unintentionally. PMID:23747649

  7. Inhibitory self-control moderates the effect of changed implicit food evaluations on snack food consumption.

    Science.gov (United States)

    Haynes, Ashleigh; Kemps, Eva; Moffitt, Robyn

    2015-07-01

    The current study used a modified implicit association test (IAT) to change implicit evaluations of unhealthy snack food and tested its effects on subsequent consumption. Furthermore, we investigated whether these effects were moderated by inhibitory self-control. A sample of 148 women (17-25 years) motivated to manage weight through healthy eating completed an IAT intervention, and pre- and post-intervention IATs assessing implicit evaluations of unhealthy food. The intervention IAT trained participants to pair unhealthy food stimuli with either positive or negative stimuli. A task disguised as a taste-test was used to assess consumption of unhealthy snack foods. Inhibitory self-control was measured using a self-report scale. As predicted, the implicit evaluation of unhealthy food became more negative from pre- to post-training among participants in the food negative pairing condition; however, there was no corresponding change in the food positive pairing condition. The effect of the training on snack consumption was moderated by inhibitory self-control with only participants low in inhibitory self-control having lower snack intake following the food negative training. This finding is consistent with dual-process models of behaviour which predict that self-control capacity renders impulses less influential on behaviour. Furthermore, it suggests that an intervention that retrains implicit food evaluations could be effective at reducing unhealthy eating, particularly among those with low inhibitory self-control. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists.

    Directory of Open Access Journals (Sweden)

    Kristy Martin

    Full Text Available Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists.After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control for 30 min (mental exertion condition, or an easy cognitive task for 10 min (control condition in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE were recorded.The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001. During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014. There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502. Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups.The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling

  9. Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists.

    Science.gov (United States)

    Martin, Kristy; Staiano, Walter; Menaspà, Paolo; Hennessey, Tom; Marcora, Samuele; Keegan, Richard; Thompson, Kevin G; Martin, David; Halson, Shona; Rattray, Ben

    2016-01-01

    Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists. After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control) for 30 min (mental exertion condition), or an easy cognitive task for 10 min (control condition) in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE) were recorded. The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001). During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014). There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502). Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups. The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling performance

  10. The effects of inhibitory control training for preschoolers on reasoning ability and neural activity

    DEFF Research Database (Denmark)

    Liu, Qian; Zhu, Xinyi; Ziegler, Albert

    2015-01-01

    Inhibitory control (including response inhibition and interference control) develops rapidly during the preschool period and is important for early cognitive development. This study aimed to determine the training and transfer effects on response inhibition in young children. Children....../week, for 3 weeks. Several cognitive tasks (involving inhibitory control, working memory, and fluid intelligence) were used to evaluate the transfer effects, and electroencephalography (EEG) was performed during a go/no-go task. Progress on the trained game was significant, while performance on a reasoning...

  11. Mother-Child Interactions and Externalizing Behavior Problems in Preschoolers over Time : Inhibitory Control as a Mediator

    NARCIS (Netherlands)

    van Dijk, Rianne; Dekovic, Maja; Bunte, Tessa L; Schoemaker, Kim; Zondervan-Zwijnenburg, Mariëlle; Espy, Kimberly A; Matthys, Walter

    2017-01-01

    Previous research has shown links between parenting and externalizing behavior problems in young children over time. Associations between inhibitory control, one of the executive functions, and externalizing behavior problems are widely established as well. Yet, the role of inhibitory control in the

  12. [Working memory and executive control: inhibitory processes in updating and random generation tasks].

    Science.gov (United States)

    Macizo, Pedro; Bajo, Teresa; Soriano, Maria Felipa

    2006-02-01

    Working Memory (WM) span predicts subjects' performance in control executive tasks and, in addition, it has been related to the capacity to inhibit irrelevant information. In this paper we investigate the role of WM span in two executive tasks focusing our attention on inhibitory components of both tasks. High and low span participants recalled targets words rejecting irrelevant items at the same time (Experiment 1) and they generated random numbers (Experiment 2). Results showed a clear relation between WM span and performance in both tasks. In addition, analyses of intrusion errors (Experiment 1) and stereotyped responses (Experiment 2) indicated that high span individuals were able to efficiently use the inhibitory component implied in both tasks. The pattern of data provides support to the relation between WM span and control executive tasks through an inhibitory mechanism.

  13. The Role of Inhibitory Control in the Development of Human Figure Drawing in Young Children

    Science.gov (United States)

    Riggs, Kevin J.; Jolley, Richard P.; Simpson, Andrew

    2013-01-01

    We investigated the role of inhibitory control in young children's human figure drawing. We used the Bear-Dragon task as a measure of inhibitory control and used the classification system devised by Cox and Parkin to measure the development of human figure drawing. We tested 50 children aged between 40 and 64 months. Regression analysis showed…

  14. Food specific inhibitory control under negative mood in binge-eating disorder: Evidence from a multimethod approach.

    Science.gov (United States)

    Leehr, Elisabeth J; Schag, Kathrin; Dresler, Thomas; Grosse-Wentrup, Moritz; Hautzinger, Martin; Fallgatter, Andreas J; Zipfel, Stephan; Giel, Katrin E; Ehlis, Ann-Christine

    2018-02-01

    Inhibitory control has been discussed as a developmental and maintenance factor in binge-eating disorder (BED). The current study is the first aimed at investigating inhibitory control in a negative mood condition on a psychophysiological and behavioral level in BED with a combination of electroencephalography (EEG) and eye tracking (ET). We conducted a combined EEG and ET study with overweight individuals with BED (BED+, n = 24, mean age = 31, mean BMI = 35 kg/m 2 ) and without BED (BED-, n = 23, mean age = 28, mean BMI = 35 kg/m 2 ) and a normal-weight (NWC, n = 26, mean age 28, mean BMI = 22 kg/m 2 ) control group. We assessed self-report data regarding impulsivity and emotion regulation as well as the processing of food stimuli under negative mood in an antisaccade task. Main outcome variables comprise event-related potentials (ERP) regarding conflict processing (N2) and performance monitoring (error-related negativity [ERN/Ne]) assessed by EEG and inhibitory control (errors in the first and second saccade) assessed by ET. BED+ patients reported increased impulsivity and higher emotion regulation difficulties compared with the other groups. The eye tracking data revealed impaired inhibitory control in BED+ compared with both control groups. Further, we found preliminary evidence from EEG recordings that conflict processing might be less thorough in the BED+ sample as well as in the NWC sample. In the BED+ sample this might be connected to the inhibitory control deficits on behavioral level. While the BED- sample showed increased conflict processing latencies (N2 latencies), which might indicate a compensation mechanism, the BED+ sample did not show such a mechanism. Performance monitoring (ERN/Ne latencies and amplitudes) was not impaired in the BED+ sample compared with both control samples. Participants with BED reported higher impulsivity and lower emotion regulation capacities. The combined investigation of electrocortical processes and

  15. Reduced Inhibitory Control Mediates the Relationship Between Cortical Thickness in the Right Superior Frontal Gyrus and Body Mass Index.

    Science.gov (United States)

    Lavagnino, Luca; Mwangi, Benson; Bauer, Isabelle E; Cao, Bo; Selvaraj, Sudhakar; Prossin, Alan; Soares, Jair C

    2016-08-01

    Unhealthy eating behaviors often develop in the setting of inadequate inhibitory control, a function broadly ascribed to the prefrontal cortex (PFC). Regulation of inhibitory control by the PFC and its anatomical components and their contribution to increasing body mass index (BMI) are poorly understood. To study the role of PFC in the regulation of inhibitory control and body weight, we examined measures of cortical thickness in PFC sub-regions, inhibitory control (color-word interference task (CWIT)), and BMI in 91 healthy volunteers. We tested the predictive effect of PFC sub-regional cortical thickness on BMI and mediation by inhibitory control measured with CWIT. Measures of depression (BDI-II), anxiety (STAI-T) and trauma-related symptoms (TSC-40) were collected; the disinhibition scale of the three-factor eating questionnaire (TFEQ) was used to assess disinhibited eating. We then tested the relationship between BD-II, STAI-T, TSC-40, TFEQ, CWIT, and BMI with correlation analyses. Right superior frontal gyrus cortical thickness significantly predicted BMI (β=-0.91; t=-3.2; p=0.002). Mediation analysis showed a significant indirect effect of cortical thickness on BMI mediated by inhibitory control (95% CI=-6.1, -0.67). BMI was unrelated to BDI-II, STAI-T, TSC-40, or TFEQ scores. We found an inverse relationship between cortical thickness in the right-superior frontal gyrus and BMI, which was fully mediated by inhibitory control neurocognitive performance. Our results suggest possible targets for neuromodulation in obesity (ie superior frontal gyrus) and a quantifiable mediator of their effects (ie inhibitory control).

  16. The Contribution of Inhibitory Control to Preschoolers' Social-Emotional Competence

    Science.gov (United States)

    Rhoades, Brittany L.; Greenberg, Mark T.; Domitrovich, Celene E.

    2009-01-01

    Social-emotional competence is a key developmental task during early childhood. This study examined concurrent relationships between maternal education and employment status, children's sex, ethnicity, age, receptive vocabulary, emotional knowledge, attention skills, inhibitory control and social-emotional competence in a sample of 146 preschool,…

  17. Monetary rewards modulate inhibitory control

    Directory of Open Access Journals (Sweden)

    Paula Marcela Herrera

    2014-05-01

    Full Text Available The ability to override a dominant response, often referred to as behavioural inhibiton, is considered a key element of executive cognition. Poor behavioural inhibition is a defining characteristic of several neurological and psychiatric populations. Recently, there has been increasing interest in the motivational dimension of behavioural inhibition, with some experiments incorporating emotional contingencies in classical inhibitory paradigms such as the Go/Nogo and Stop Signal Tasks. Several studies have reported a positive modulatory effect of reward on the performance of such tasks in pathological conditions such as substance abuse, pathological gambling, and ADHD. However, experiments that directly investigate the modulatory effects of reward magnitudes on the performance of inhibitory paradigms are rare and consequently, little is known about the finer grained relationship between motivation and self-control. Here, we probed the effect of reward and reward magnitude on behavioural inhibition using two modified version of the widely used Stop Signal Task. The first task compared no reward with reward, whilst the other compared two different reward magnitudes. The reward magnitude effect was confirmed by the second study, whereas it was less compelling in the first study, possibly due to the effect of having no reward in some conditions. In addition, our results showed a kick start effect over global performance measures. More specifically, there was a long lasting improvement in performance throughout the task, when participants received the highest reward magnitudes at the beginning of the protocol. These results demonstrate that individuals’ behavioural inhibition capacities are dynamic not static because they are modulated by the reward magnitude and initial reward history of the task at hand.

  18. The role of dopamine in inhibitory control in smokers and non-smokers: a pharmacological fMRI study

    NARCIS (Netherlands)

    Luijten, Maartje; Veltman, Dick J.; Hester, Robert; Smits, Marion; Nijs, Ilse M. T.; Pepplinkhuizen, Lolke; Franken, Ingmar H. A.

    2013-01-01

    Contemporary theoretical models of substance dependence posit that deficits in inhibitory control play an important role in substance dependence. The neural network underlying inhibitory control and its association with substance dependence have been widely investigated. However, the pharmacology of

  19. The role of dopamine in inhibitory control in smokers and non-smokers: A pharmacological fMRI study

    NARCIS (Netherlands)

    Luijten, M.; Veltman, D.J.; Hester, R.; Smits, M.; Nijs, I.M.T.; Pepplinkhuizen, L.; Franken, I.H.A.

    2013-01-01

    Contemporary theoretical models of substance dependence posit that deficits in inhibitory control play an important role in substance dependence. The neural network underlying inhibitory control and its association with substance dependence have been widely investigated. However, the pharmacology of

  20. Can musical engagement alleviate age-related decline in inhibitory control?

    NARCIS (Netherlands)

    Vromans, R.D.; Nilsenova, Marie; Papafragou, A.; Grodner, D.; Mirman, D.; Trueswell, J. C.

    2016-01-01

    The purpose of our study was to determine whether active musical engagement alleviates decline in inhibitory control due to cognitive aging. Given that musical training in young adults has been shown to improve attentional performance, we can expect this benefit to persist for older adults as well.

  1. Deviant Peer Behavior and Adolescent Delinquency: Protective Effects of Inhibitory Control, Planning, or Decision Making?

    Science.gov (United States)

    Hinnant, J Benjamin; Forman-Alberti, Alissa B

    2018-05-09

    We examined relations between adolescent perceptions of deviant peer behavior and delinquency as moderated by inhibitory control, planning, and decision making in the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development at age 15 (N = 991). Adolescents reported perceptions of deviant peer behavior. Inhibitory control, planning, and decision making were assessed behaviorally. Delinquency was evaluated with a latent variable comprised of parent-guardian perceptions of adolescent delinquency and adolescent self-reports. Only inhibitory control moderated the relationship between deviant peer behavior and delinquency, showing that better inhibition protected against delinquency in contexts of high levels of adolescent perceptions of deviant peer behavior. Findings are discussed in the context of theories of adolescent delinquency and risk taking. © 2018 Society for Research on Adolescence.

  2. Attention problems, inhibitory control, and intelligence index overlapping genetic factors: a study in 9-, 12-, and 18-year-old twins.

    Science.gov (United States)

    Polderman, Tinca J C; de Geus, Eco J C; Hoekstra, Rosa A; Bartels, Meike; van Leeuwen, Marieke; Verhulst, Frank C; Posthuma, Danielle; Boomsma, Dorret I

    2009-05-01

    It is assumed that attention problems (AP) are related to impaired executive functioning. We investigated the association between AP and inhibitory control and tested to what extent the association was due to genetic factors shared with IQ. Data were available from 3 independent samples of 9-, 12-, and 18-year-old twins and their siblings (1,209 participants). AP were assessed with checklists completed by multiple informants. Inhibitory control was measured with the Stroop Color Word Task (Stroop, 1935), and IQ with the Wechsler Intelligence Scale for Children (Wechsler et al., 2002) or Wechsler Adult Intelligence Scale (Wechsler, 1997). AP and inhibitory control were only correlated in the 12-year-old cohort (r = .18), but appeared non-significant after controlling for IQ. Significant correlations existed between AP and IQ in 9- and 12-year olds (r = -.26/-.34). Inhibitory control and IQ were correlated in all cohorts (r = -.16, -.24 and -.35, respectively). Genetic factors that influenced IQ also influenced inhibitory control. We conclude that the association between AP and inhibitory control as reported in the literature may largely derive from genetic factors that are shared with IQ.

  3. Inhibitory Control and Hedonic Response towards Food Interactively Predict Success in a Weight Loss Programme for Adults with Obesity

    Directory of Open Access Journals (Sweden)

    Timo Brockmeyer

    2016-10-01

    Full Text Available Objective: Low inhibitory control and strong hedonic response towards food are considered to contribute to overeating and obesity. Based on previous research, the present study aimed at examining the potentially crucial interplay between these two factors in terms of long-term weight loss in people with obesity. Methods: BMI, inhibitory control towards food, and food liking were assessed in obese adults prior to a weight reduction programme (OPTIFAST® 52. After the weight reduction phase (week 13 and the weight loss maintenance phase (week 52, participants' BMI was re-assessed. Results: Baseline BMI, inhibitory control and food liking alone did not predict weight loss. As hypothesised, however, inhibitory control and food liking interactively predicted weight loss from baseline to week 13 and to week 52 (albeit the latter effect was less robust. Participants with low inhibitory control and marked food liking were less successful in weight reduction. Conclusion: These findings underscore the relevance of the interplay between cognitive control and food reward valuation in the maintenance of obesity.

  4. Inhibitory Control during Emotional Distraction across Adolescence and Early Adulthood

    Science.gov (United States)

    Cohen-Gilbert, Julia E.; Thomas, Kathleen M.

    2013-01-01

    This study investigated the changing relation between emotion and inhibitory control during adolescence. One hundred participants between 11 and 25 years of age performed a go-nogo task in which task-relevant stimuli (letters) were presented at the center of large task-irrelevant images depicting negative, positive, or neutral scenes selected from…

  5. Inhibitory control and the onset of combustible cigarette, e-cigarette, and hookah use in early adolescence: The moderating role of socioeconomic status.

    Science.gov (United States)

    Riggs, Nathaniel R; Pentz, Mary Ann

    2016-01-01

    The purpose of the study was to test the moderating influence of socioeconomic status (SES) on the associations between inhibitory control and the onset of combustible cigarette, electronic (e-) cigarette, and hookah use in early adolescence. A total of 407 adolescents self-reported nicotine use, inhibitory control, and SES. The hypothesis that inhibitory control would be significantly associated with nicotine use onset (i.e., combustible cigarettes, e-cigarettes, and hookah) only under the condition of low SES was tested. Direct associations were found for inhibitory control on "ever use" of all three nicotine use variables. A moderating effect was also found whereby low inhibitory control was significantly associated with nicotine use onset when participants were from low, but not high, SES families. Findings illustrate one contextual condition under which inhibitory control is associated with early onset of nicotine use.

  6. Inhibitory Control in the Cortico-Basal Ganglia-Thalamocortical Loop: Complex Regulation and Interplay with Memory and Decision Processes.

    Science.gov (United States)

    Wei, Wei; Wang, Xiao-Jing

    2016-12-07

    We developed a circuit model of spiking neurons that includes multiple pathways in the basal ganglia (BG) and is endowed with feedback mechanisms at three levels: cortical microcircuit, corticothalamic loop, and cortico-BG-thalamocortical system. We focused on executive control in a stop signal task, which is known to depend on BG across species. The model reproduces a range of experimental observations and shows that the newly discovered feedback projection from external globus pallidus to striatum is crucial for inhibitory control. Moreover, stopping process is enhanced by the cortico-subcortical reverberatory dynamics underlying persistent activity, establishing interdependence between working memory and inhibitory control. Surprisingly, the stop signal reaction time (SSRT) can be adjusted by weights of certain connections but is insensitive to other connections in this complex circuit, suggesting novel circuit-based intervention for inhibitory control deficits associated with mental illness. Our model provides a unified framework for inhibitory control, decision making, and working memory. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Comparison of the acute effects of high-intensity interval training and continuous aerobic walking on inhibitory control.

    Science.gov (United States)

    Kao, Shih-Chun; Westfall, Daniel R; Soneson, Jack; Gurd, Brendon; Hillman, Charles H

    2017-09-01

    The purpose of this study was to investigate the effects of a single bout of high-intensity interval training (HIIT) and continuous aerobic exercise (CAE) on inhibitory control. The P3 component of the stimulus-locked ERP was collected in 64 young adults during a modified flanker task following 20 min of seated rest, 20 min of CAE, and 9 min of HIIT on separate days in counterbalanced order. Participants exhibited shorter overall reaction time following CAE and HIIT compared to seated rest. Response accuracy improved following HIIT in the task condition requiring greater inhibitory control compared to seated rest and CAE. P3 amplitude was larger following CAE compared to seated rest and HIIT. Decreased P3 amplitude and latency were observed following HIIT compared to seated rest. The current results replicated previous findings indicating the beneficial effect of acute CAE on behavioral and neuroelectric indices of inhibitory control. With a smaller duration and volume of exercise, a single bout of HIIT resulted in additional improvements in inhibitory control, paralleled by a smaller and more efficient P3 component. In sum, the current study demonstrated that CAE and HIIT differentially facilitate inhibitory control and its underlying neuroelectric activation, and that HIIT may be a time-efficient approach for enhancing cognitive health. © 2017 Society for Psychophysiological Research.

  8. Inhibitory coupling between inhibitory interneurons in the spinal cord dorsal horn

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    Ribeiro-da-Silva Alfredo

    2009-05-01

    Full Text Available Abstract Local inhibitory interneurons in the dorsal horn play an important role in the control of excitability at the segmental level and thus determine how nociceptive information is relayed to higher structures. Regulation of inhibitory interneuron activity may therefore have critical consequences on pain perception. Indeed, disinhibition of dorsal horn neuronal networks disrupts the balance between excitation and inhibition and is believed to be a key mechanism underlying different forms of pain hypersensitivity and chronic pain states. In this context, studying the source and the synaptic properties of the inhibitory inputs that the inhibitory interneurons receive is important in order to predict the impact of drug action at the network level. To address this, we studied inhibitory synaptic transmission in lamina II inhibitory interneurons identified under visual guidance in spinal slices taken from transgenic mice expressing enhanced green fluorescent protein (EGFP under the control of the GAD promoter. The majority of these cells fired tonically to a long depolarizing current pulse. Monosynaptically evoked inhibitory postsynaptic currents (eIPSCs in these cells were mediated by both GABAA and glycine receptors. Consistent with this, both GABAA and glycine receptor-mediated miniature IPSCs were recorded in all of the cells. These inhibitory inputs originated at least in part from local lamina II interneurons as verified by simultaneous recordings from pairs of EGFP+ cells. These synapses appeared to have low release probability and displayed potentiation and asynchronous release upon repeated activation. In summary, we report on a previously unexamined component of the dorsal horn circuitry that likely constitutes an essential element of the fine tuning of nociception.

  9. The development of inhibitory control in preschool children: effects of "executive skills" training.

    Science.gov (United States)

    Dowsett, S M; Livesey, D J

    2000-03-01

    As one of several processes involved in the executive functioning of the cognitive system, inhibitory control plays a significant role in determining how various mental processes work together in the successful performance of a task. Studies of response inhibition have shown that although 3-year-old children have the cognitive capacity to learn the rules required for response control, indicated by the correct verbal response, developmental constraints prevent them from withholding the correct response (Bell & Livesey, 1985; Livesey & Morgan, 1991). Some argue that these abulic dissociations are relative to children's ability to reflect on the rules required for response control (Zelazo, Reznick, & Pinon, 1995). The current study showed that repeated exposure to tasks facilitating the acquisition of increasingly complex rule structures could improve inhibitory control (as measured by a go/no-go discrimination learning task), even in children aged 3 years. These tasks included a variant of Diamond and Boyer's (1989) modified version of the Wisconsin Card Sort Task and a simplification of the change paradigm (Logan & Burkell, 1986). It is argued that experience with these tasks increased the acquisition of complex rules by placing demands on executive processes. This includes response control and other executive functions, such as representational flexibility, the ability to maintain information in working memory, the selective control of attention, and proficiency at error correction. The role of experiential variables in the development of inhibitory control is discussed in terms of the interaction between neural development and appropriate executive task experience in the early years. Copyright 2000 John Wiley & Sons, Inc.

  10. Acute effects of alcohol on inhibitory control and simulated driving in DUI offenders.

    Science.gov (United States)

    Van Dyke, Nicholas; Fillmore, Mark T

    2014-06-01

    The public health costs associated with alcohol-related traffic accidents have prompted considerable research aimed at identifying characteristics of individuals who drive under the influence (DUI) in order to improve treatment and prevention strategies. Survey studies consistently show that DUI offenders self-report higher levels of impulsivity compared to their nonoffending counterparts. However, little is known about how individuals with a DUI history respond under alcohol. Inhibitory control is a behavioral component of impulsivity thought to underlie risky drinking and driving behaviors. The present study examined the degree to which DUI drivers display deficits of inhibitory control in response to alcohol and the degree to which alcohol impaired their simulated driving performance. It was hypothesized that DUI offenders would display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance. Young adult drivers with a history of DUI and a demographically-comparable group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg dose of alcohol and a placebo. Inhibitory control was measured by using a cued go/no-go task. Drivers then completed a driving simulation task that yielded multiple indicators of driving performance, such as within-lane deviation, steering rate, centerline crossings and road edge excursions, and drive speed. Results showed that although DUI offenders self-reported greater levels of impulsivity than did controls, no group differences were observed in the degree to which alcohol impaired inhibitory control and driving performance. The findings point to the need to identify other aspects of behavioral dysfunction underlying the self-reported impulsivity among DUI offenders, and to better understand the specific driving situations that might pose greater risk to DUI offenders. The systematic study of candidate cognitive deficits in DUI offenders will provide important

  11. Inhibitory Control, but Not Prolonged Object-Related Experience Appears to Affect Physical Problem-Solving Performance of Pet Dogs

    Science.gov (United States)

    Müller, Corsin A.; Riemer, Stefanie; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

    2016-01-01

    Human infants develop an understanding of their physical environment through playful interactions with objects. Similar processes may influence also the performance of non-human animals in physical problem-solving tasks, but to date there is little empirical data to evaluate this hypothesis. In addition or alternatively to prior experiences, inhibitory control has been suggested as a factor underlying the considerable individual differences in performance reported for many species. Here we report a study in which we manipulated the extent of object-related experience for a cohort of dogs (Canis familiaris) of the breed Border Collie over a period of 18 months, and assessed their level of inhibitory control, prior to testing them in a series of four physical problem-solving tasks. We found no evidence that differences in object-related experience explain variability in performance in these tasks. It thus appears that dogs do not transfer knowledge about physical rules from one physical problem-solving task to another, but rather approach each task as a novel problem. Our results, however, suggest that individual performance in these tasks is influenced in a complex way by the subject’s level of inhibitory control. Depending on the task, inhibitory control had a positive or a negative effect on performance and different aspects of inhibitory control turned out to be the best predictors of individual performance in the different tasks. Therefore, studying the interplay between inhibitory control and problem-solving performance will make an important contribution to our understanding of individual and species differences in physical problem-solving performance. PMID:26863141

  12. Inhibitory Control, but Not Prolonged Object-Related Experience Appears to Affect Physical Problem-Solving Performance of Pet Dogs.

    Directory of Open Access Journals (Sweden)

    Corsin A Müller

    Full Text Available Human infants develop an understanding of their physical environment through playful interactions with objects. Similar processes may influence also the performance of non-human animals in physical problem-solving tasks, but to date there is little empirical data to evaluate this hypothesis. In addition or alternatively to prior experiences, inhibitory control has been suggested as a factor underlying the considerable individual differences in performance reported for many species. Here we report a study in which we manipulated the extent of object-related experience for a cohort of dogs (Canis familiaris of the breed Border Collie over a period of 18 months, and assessed their level of inhibitory control, prior to testing them in a series of four physical problem-solving tasks. We found no evidence that differences in object-related experience explain variability in performance in these tasks. It thus appears that dogs do not transfer knowledge about physical rules from one physical problem-solving task to another, but rather approach each task as a novel problem. Our results, however, suggest that individual performance in these tasks is influenced in a complex way by the subject's level of inhibitory control. Depending on the task, inhibitory control had a positive or a negative effect on performance and different aspects of inhibitory control turned out to be the best predictors of individual performance in the different tasks. Therefore, studying the interplay between inhibitory control and problem-solving performance will make an important contribution to our understanding of individual and species differences in physical problem-solving performance.

  13. Inhibitory Control, but Not Prolonged Object-Related Experience Appears to Affect Physical Problem-Solving Performance of Pet Dogs.

    Science.gov (United States)

    Müller, Corsin A; Riemer, Stefanie; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

    2016-01-01

    Human infants develop an understanding of their physical environment through playful interactions with objects. Similar processes may influence also the performance of non-human animals in physical problem-solving tasks, but to date there is little empirical data to evaluate this hypothesis. In addition or alternatively to prior experiences, inhibitory control has been suggested as a factor underlying the considerable individual differences in performance reported for many species. Here we report a study in which we manipulated the extent of object-related experience for a cohort of dogs (Canis familiaris) of the breed Border Collie over a period of 18 months, and assessed their level of inhibitory control, prior to testing them in a series of four physical problem-solving tasks. We found no evidence that differences in object-related experience explain variability in performance in these tasks. It thus appears that dogs do not transfer knowledge about physical rules from one physical problem-solving task to another, but rather approach each task as a novel problem. Our results, however, suggest that individual performance in these tasks is influenced in a complex way by the subject's level of inhibitory control. Depending on the task, inhibitory control had a positive or a negative effect on performance and different aspects of inhibitory control turned out to be the best predictors of individual performance in the different tasks. Therefore, studying the interplay between inhibitory control and problem-solving performance will make an important contribution to our understanding of individual and species differences in physical problem-solving performance.

  14. Proactive behavior, but not inhibitory control, predicts repeated innovation by spotted hyenas tested with a multi-access box.

    Science.gov (United States)

    Johnson-Ulrich, Lily; Johnson-Ulrich, Zoe; Holekamp, Kay

    2018-05-01

    Innovation is widely linked to cognitive ability, brain size, and adaptation to novel conditions. However, successful innovation appears to be influenced by both cognitive factors, such as inhibitory control, and non-cognitive behavioral traits. We used a multi-access box (MAB) paradigm to measure repeated innovation, the number of unique innovations learned across trials, by 10 captive spotted hyenas (Crocuta crocuta). Spotted hyenas are highly innovative in captivity and also display striking variation in behavioral traits, making them good model organisms for examining the relationship between innovation and other behavioral traits. We measured persistence, motor diversity, motivation, activity, efficiency, inhibitory control, and neophobia demonstrated by hyenas while interacting with the MAB. We also independently assessed inhibitory control with a detour cylinder task. Most hyenas were able to solve the MAB at least once, but only four hyenas satisfied learning criteria for all four possible solutions. Interestingly, neither measure of inhibitory control predicted repeated innovation. Instead, repeated innovation was predicted by a proactive syndrome of behavioral traits that included high persistence, high motor diversity, high activity and low neophobia. Our results suggest that this proactive behavioral syndrome may be more important than inhibitory control for successful innovation with the MAB by members of this species.

  15. Eye Gaze and Aging: Selective and Combined Effects of Working Memory and Inhibitory Control

    Directory of Open Access Journals (Sweden)

    Trevor J. Crawford

    2017-11-01

    Full Text Available Eye-tracking is increasingly studied as a cognitive and biological marker for the early signs of neuropsychological and psychiatric disorders. However, in order to make further progress, a more comprehensive understanding of the age-related effects on eye-tracking is essential. The antisaccade task requires participants to make saccadic eye movements away from a prepotent stimulus. Speculation on the cause of the observed age-related differences in the antisaccade task largely centers around two sources of cognitive dysfunction: inhibitory control (IC and working memory (WM. The IC account views cognitive slowing and task errors as a direct result of the decline of inhibitory cognitive mechanisms. An alternative theory considers that a deterioration of WM is the cause of these age-related effects on behavior. The current study assessed IC and WM processes underpinning saccadic eye movements in young and older participants. This was achieved with three experimental conditions that systematically varied the extent to which WM and IC were taxed in the antisaccade task: a memory-guided task was used to explore the effect of increasing the WM load; a Go/No-Go task was used to explore the effect of increasing the inhibitory load; a ‘standard’ antisaccade task retained the standard WM and inhibitory loads. Saccadic eye movements were also examined in a control condition: the standard prosaccade task where the load of WM and IC were minimal or absent. Saccade latencies, error rates and the spatial accuracy of saccades of older participants were compared to the same measures in healthy young controls across the conditions. The results revealed that aging is associated with changes in both IC and WM. Increasing the inhibitory load was associated with increased reaction times in the older group, while the increased WM load and the inhibitory load contributed to an increase in the antisaccade errors. These results reveal that aging is associated with

  16. Eye Gaze and Aging: Selective and Combined Effects of Working Memory and Inhibitory Control.

    Science.gov (United States)

    Crawford, Trevor J; Smith, Eleanor S; Berry, Donna M

    2017-01-01

    Eye-tracking is increasingly studied as a cognitive and biological marker for the early signs of neuropsychological and psychiatric disorders. However, in order to make further progress, a more comprehensive understanding of the age-related effects on eye-tracking is essential. The antisaccade task requires participants to make saccadic eye movements away from a prepotent stimulus. Speculation on the cause of the observed age-related differences in the antisaccade task largely centers around two sources of cognitive dysfunction: inhibitory control (IC) and working memory (WM). The IC account views cognitive slowing and task errors as a direct result of the decline of inhibitory cognitive mechanisms. An alternative theory considers that a deterioration of WM is the cause of these age-related effects on behavior. The current study assessed IC and WM processes underpinning saccadic eye movements in young and older participants. This was achieved with three experimental conditions that systematically varied the extent to which WM and IC were taxed in the antisaccade task: a memory-guided task was used to explore the effect of increasing the WM load; a Go/No-Go task was used to explore the effect of increasing the inhibitory load; a 'standard' antisaccade task retained the standard WM and inhibitory loads. Saccadic eye movements were also examined in a control condition: the standard prosaccade task where the load of WM and IC were minimal or absent. Saccade latencies, error rates and the spatial accuracy of saccades of older participants were compared to the same measures in healthy young controls across the conditions. The results revealed that aging is associated with changes in both IC and WM. Increasing the inhibitory load was associated with increased reaction times in the older group, while the increased WM load and the inhibitory load contributed to an increase in the antisaccade errors. These results reveal that aging is associated with changes in both IC and

  17. Inhibitory Control and Working Memory in Post-Institutionalized Children

    Science.gov (United States)

    Merz, Emily C.; McCall, Robert B.; Wright, Amanda J.; Luna, Beatriz

    2013-01-01

    Inhibitory control and working memory were examined in post-institutionalized (PI) children adopted into United States families from Russian institutions. The PI sample originated from institutions that were less severely depriving than those represented in previous studies and approximated the level of psychosocial deprivation, which is characterized by adequate physical resources but a lack of consistent and responsive caregiving. PI children (N=75; 29 male) ranged in age from 8–17 years (M=12.97; SD=3.03) and were grouped according to whether they were adopted after 14 months or before 9 months. A non-adopted comparison group (N=133; 65 male) ranged in age from 8–17 years (M=12.26; SD=2.75). PI children adopted after 14 months of age displayed poorer performance on the stop-signal and spatial span tasks relative to PI children adopted before 9 months of age after controlling for age at assessment. The two PI groups did not differ in their performance on a spatial self-ordered search task. Older-adopted PI children also showed poorer spatial span task performance compared to non-adopted children, but younger-adopted PI children did not. Task performance was significantly associated with parent-rated hyperactive-impulsive behavior in everyday contexts. These findings suggest that exposure to prolonged early institutional deprivation may be linked with inhibitory control and working memory difficulties years after adoption. PMID:23519375

  18. Childhood maltreatment is associated with a sex-dependent functional reorganization of a brain inhibitory control network.

    Science.gov (United States)

    Elton, Amanda; Tripathi, Shanti P; Mletzko, Tanja; Young, Jonathan; Cisler, Josh M; James, G Andrew; Kilts, Clinton D

    2014-04-01

    Childhood adversity represents a major risk factor for drug addiction and other mental disorders. However, the specific mechanisms by which childhood adversity impacts human brain organization to confer greater vulnerability for negative outcomes in adulthood is largely unknown. As an impaired process in drug addiction, inhibitory control of behavior was investigated as a target of childhood maltreatment (abuse and neglect). Forty adults without Axis-I psychiatric disorders (21 females) completed a Childhood Trauma Questionnaire (CTQ) and underwent functional MRI (fMRI) while performing a stop-signal task. A group independent component analysis identified a putative brain inhibitory control network. Graph theoretical analyses and structural equation modeling investigated the impact of childhood maltreatment on the functional organization of this neural processing network. Graph theory outcomes revealed sex differences in the relationship between network functional connectivity and inhibitory control which were dependent on the severity of childhood maltreatment exposure. A network effective connectivity analysis indicated that a maltreatment dose-related negative modulation of dorsal anterior cingulate (dACC) activity by the left inferior frontal cortex (IFC) predicted better response inhibition and lesser attention deficit hyperactivity disorder (ADHD) symptoms in females, but poorer response inhibition and greater ADHD symptoms in males. Less inhibition of the right IFC by dACC in males with higher CTQ scores improved inhibitory control ability. The childhood maltreatment-related reorganization of a brain inhibitory control network provides sex-dependent mechanisms by which childhood adversity may confer greater risk for drug use and related disorders and by which adaptive brain responses protect individuals from this risk factor. Copyright © 2013 Wiley Periodicals, Inc.

  19. Inhibitory control effects in adolescent binge eating and consumption of sugar-sweetened beverages and snacks.

    Science.gov (United States)

    Ames, Susan L; Kisbu-Sakarya, Yasemin; Reynolds, Kim D; Boyle, Sarah; Cappelli, Christopher; Cox, Matthew G; Dust, Mark; Grenard, Jerry L; Mackinnon, David P; Stacy, Alan W

    2014-10-01

    Inhibitory control and sensitivity to reward are relevant to the food choices individuals make frequently. An imbalance of these systems can lead to deficits in decision-making that are relevant to food ingestion. This study evaluated the relationship between dietary behaviors - binge eating and consumption of sweetened beverages and snacks - and behavioral control processes among 198 adolescents, ages 14 to 17. Neurocognitive control processes were assessed with the Iowa Gambling Task (IGT), a generic Go/No-Go task, and a food-specific Go/No-Go task. The food-specific version directly ties the task to food cues that trigger responses, addressing an integral link between cue-habit processes. Diet was assessed with self-administered food frequency and binge eating questionnaires. Latent variable models revealed marked gender differences. Inhibitory problems on the food-specific and generic Go/No-Go tasks were significantly correlated with binge eating only in females, whereas inhibitory problems measured with these tasks were the strongest correlates of sweet snack consumption in males. Higher BMI percentile and sedentary behavior also predicted binge eating in females and sweet snack consumption in males. Inhibitory problems on the generic Go/No-Go, poorer affective decision-making on the IGT, and sedentary behavior were associated with sweetened beverage consumption in males, but not females. The food-specific Go/No-Go was not predictive in models evaluating sweetened beverage consumption, providing some initial discriminant validity for the task, which consisted of sweet/fatty snacks as no-go signals and no sugar-sweetened beverage signals. This work extends research findings, revealing gender differences in inhibitory function relevant to behavioral control. Further, the findings contribute to research implicating the relevance of cues in habitual behaviors and their relationship to snack food consumption in an understudied population of diverse adolescents not

  20. Acute alcohol effects on inhibitory control and implicit cognition: implications for loss of control over drinking

    NARCIS (Netherlands)

    Field, M.; Wiers, R.W.; Christiansen, P.; Fillmore, M.T.; Verster, J.C.

    2010-01-01

    Alcohol impairs inhibitory control, and it alters implicit alcohol cognitions including attentional bias and implicit associations. These effects are seen after doses of alcohol which do not lead to global impairments in cognitive performance. We review studies which demonstrate that the effects of

  1. Inseparability of Go and Stop in Inhibitory Control: Go Stimulus Discriminability Affects Stopping Behavior.

    Science.gov (United States)

    Ma, Ning; Yu, Angela J

    2016-01-01

    Inhibitory control, the ability to stop or modify preplanned actions under changing task conditions, is an important component of cognitive functions. Two lines of models of inhibitory control have previously been proposed for human response in the classical stop-signal task, in which subjects must inhibit a default go response upon presentation of an infrequent stop signal: (1) the race model, which posits two independent go and stop processes that race to determine the behavioral outcome, go or stop; and (2) an optimal decision-making model, which posits that observers decides whether and when to go based on continually (Bayesian) updated information about both the go and stop stimuli. In this work, we probe the relationship between go and stop processing by explicitly manipulating the discrimination difficulty of the go stimulus. While the race model assumes the go and stop processes are independent, and therefore go stimulus discriminability should not affect the stop stimulus processing, we simulate the optimal model to show that it predicts harder go discrimination should result in longer go reaction time (RT), lower stop error rate, as well as faster stop-signal RT. We then present novel behavioral data that validate these model predictions. The results thus favor a fundamentally inseparable account of go and stop processing, in a manner consistent with the optimal model, and contradicting the independence assumption of the race model. More broadly, our findings contribute to the growing evidence that the computations underlying inhibitory control are systematically modulated by cognitive influences in a Bayes-optimal manner, thus opening new avenues for interpreting neural responses underlying inhibitory control.

  2. Inseparability of Go and Stop in Inhibitory Control: Go Stimulus Discriminability Affects Stopping Behavior

    Directory of Open Access Journals (Sweden)

    Ning eMa

    2016-03-01

    Full Text Available Inhibitory control, the ability to stop or modify preplanned actions under changing task conditions, is an important component of cognitive functions. Two lines of models of inhibitory control have previously been proposed for human response in the classical stop-signal task, in which subjects must inhibit a default go response upon presentation of an infrequent stop signal: (1 the race model, which posits two independent go and stop processes that race to determine the behavioral outcome, go or stop; and (2 an optimal decision-making model, which posits that observers decides whether and when to go based on continually (Bayesian updated information about both the go and stop stimuli. In this work, we probe the relationship between go and stop processing by explicitly manipulating the discrimination difficulty of the go stimulus. While the race model assumes the go and stop processes are independent, and therefore go stimulus discriminability should not affect the stop stimulus processing, we simulate the optimal model to show that it predicts harder go discrimination results in a longer go reaction time (RT, a lower stop error rate, as well as a faster stop-signal RT. We then present novel behavioral data that validate these model predictions. The results thus favor a fundamentally inseparable account of go and stop processing, in a manner consistent with the optimal model, and contradicting the independence assumption of the race model. More broadly, our findings contribute to the growing evidence that the computations underlying inhibitory control are systematically modulated by cognitive influences in a Bayes-optimal manner, thus opening new avenues for interpreting neural responses underlying inhibitory control.

  3. Evidence for an inhibitory-control theory of the reasoning brain.

    Science.gov (United States)

    Houdé, Olivier; Borst, Grégoire

    2015-01-01

    In this article, we first describe our general inhibitory-control theory and, then, we describe how we have tested its specific hypotheses on reasoning with brain imaging techniques in adults and children. The innovative part of this perspective lies in its attempt to come up with a brain-based synthesis of Jean Piaget's theory on logical algorithms and Daniel Kahneman's theory on intuitive heuristics.

  4. Threat Interference Biases Predict Socially Anxious Behavior: The Role of Inhibitory Control and Minute of Stressor.

    Science.gov (United States)

    Gorlin, Eugenia I; Teachman, Bethany A

    2015-07-01

    The current study brings together two typically distinct lines of research. First, social anxiety is inconsistently associated with behavioral deficits in social performance, and the factors accounting for these deficits remain poorly understood. Second, research on selective processing of threat cues, termed cognitive biases, suggests these biases typically predict negative outcomes, but may sometimes be adaptive, depending on the context. Integrating these research areas, the current study examined whether conscious and/or unconscious threat interference biases (indexed by the unmasked and masked emotional Stroop) can explain unique variance, beyond self-reported anxiety measures, in behavioral avoidance and observer-rated anxious behavior during a public speaking task. Minute of speech and general inhibitory control (indexed by the color-word Stroop) were examined as within-subject and between-subject moderators, respectively. Highly socially anxious participants (N=135) completed the emotional and color-word Stroop blocks prior to completing a 4-minute videotaped speech task, which was later coded for anxious behaviors (e.g., speech dysfluency). Mixed-effects regression analyses revealed that general inhibitory control moderated the relationship between both conscious and unconscious threat interference bias and anxious behavior (though not avoidance), such that lower threat interference predicted higher levels of anxious behavior, but only among those with relatively weaker (versus stronger) inhibitory control. Minute of speech further moderated this relationship for unconscious (but not conscious) social-threat interference, such that lower social-threat interference predicted a steeper increase in anxious behaviors over the course of the speech (but only among those with weaker inhibitory control). Thus, both trait and state differences in inhibitory control resources may influence the behavioral impact of threat biases in social anxiety. Copyright © 2015

  5. Imagined Positive Emotions and Inhibitory Control: The Differentiated Effect of Pride versus Happiness

    Science.gov (United States)

    Katzir, Maayan; Eyal, Tal; Meiran, Nachshon; Kessler, Yoav

    2010-01-01

    "Inhibitory control" is a cognitive mechanism that contributes to successful self-control (i.e., adherence to a long-term goal in the face of an interfering short-term goal). This research explored the effect of imagined positive emotional events on inhibition. The authors proposed that the influence of imagined emotions on inhibition…

  6. Put on a happy face! Inhibitory control and socioemotional knowledge predict emotion regulation in 5- to 7-year-olds.

    Science.gov (United States)

    Hudson, Amanda; Jacques, Sophie

    2014-07-01

    Children's developing capacity to regulate emotions may depend on individual characteristics and other abilities, including age, sex, inhibitory control, theory of mind, and emotion and display rule knowledge. In the current study, we examined the relations between these variables and children's (N=107) regulation of emotion in a disappointing gift paradigm as well as their relations with the amount of effort to control emotion children exhibited after receiving the disappointing gift. Regression analyses were also conducted to identify unique predictors. Children's understanding of others' emotions and emotion display rules, as well as their inhibitory control skills, emerged as significant correlates of emotion regulation and predicted children's responses to the disappointing gift even after controlling for other relevant variables. Age and inhibitory control significantly predicted the amount of overt effort that went into regulating emotions, as did emotion knowledge (albeit only marginally). Together, findings suggest that effectively regulating emotions requires (a) knowledge of context-appropriate emotions along with (b) inhibitory skills to implement that knowledge. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Redox-controlled dinitrosyl formation at the diiron-oxo center of NorA.

    Science.gov (United States)

    Cramm, Rainer; Strube, Katja

    2008-01-01

    In the denitrifying bacterium Ralstonia eutropha H16, the NorA protein is coproduced with the respiratory nitric oxide (NO) reductase. NorA contains a diiron-oxo center, which can form stable adducts with dioxygen and NO. In contrast to other diiron proteins, the formation of NorA-NO requires both fully reduced protein and additional electrons. A minor fraction of in vitro NorA-NO represents a paramagnetic dinitrosyl iron complex (DNIC), while the major fraction is attributed to a DNIC of the structure {Fe(NO)(2)}, which shows no electron paramagnetic resonance. The NorA-DNIC may be formed either upon direct reaction of the protein with NO or upon incubation with nitrite due to an intrinsic nitrite reduction activity of NorA that liberates NO. NorA can be purified rapidly as a six histidine-tagged derivative from overproducing cells of Escherichia coli. This chapter describes procedures for the preparation of different redox forms of NorA for the formation of NorA adducts with NO, dioxygen, and azide, as well as for the quantification of NorA-bound NO.

  8. Modulating mimicry: Exploring the roles of inhibitory control and social understanding in 5-year-olds' behavioral mimicry.

    Science.gov (United States)

    van Schaik, Johanna E; Hunnius, Sabine

    2018-01-01

    During adult interactions, behavioral mimicry, the implicit copying of an interaction partner's postures and mannerisms, communicates liking and affiliation. While this social behavior likely develops during early childhood, it is unclear which factors contribute to its emergence. Here, the roles of inhibitory control and social understanding on 5-year-olds' behavioral mimicry were investigated. Following a social manipulation in which one experimenter shared a sticker with the child and the other experimenter kept two stickers for herself, children watched a video in which these experimenters each told a story. During this story session, children in the experimental group (n = 28) observed the experimenters perform face and hand rubbing behaviors whereas the control group (n = 23) did not see these behaviors. Children's inhibitory control was assessed using the day-night task and their social understanding was measured through a parental questionnaire. Surprisingly, group-level analyses revealed that the experimental group performed the behaviors significantly less than the control group (i.e. a negative mimicry effect) for both the sticker-sharer and sticker-keeper. Yet, the hypothesized effects of inhibitory control and social understanding were found. Inhibitory control predicted children's selective mimicry of the sticker-keeper versus sticker-sharer and children's overall mimicry was correlated with social understanding. These results provide the first indications to suggest that factors of social and cognitive development dynamically influence the emergence and specificity of behavioral mimicry during early childhood.

  9. Inhibitory control effects in adolescent binge eating and consumption of sugar-sweetened beverages and snacks

    Science.gov (United States)

    Ames, Susan L.; Kisbu-Sakarya, Yasemin; Reynolds, Kim D.; Boyle, Sarah; Cappelli, Christopher; Cox, Matthew G.; Dust, Mark; Grenard, Jerry L.; Mackinnon, David P.; Stacy, Alan W.

    2014-01-01

    Inhibitory control and sensitivity to reward are relevant to the food choices individuals make frequently. An imbalance of these systems can lead to deficits in decision-making that are relevant to food ingestion. This study evaluated the relationship between dietary behaviors – binge eating and consumption of sweetened beverages and snacks - and behavioral control processes, among 198 ethnically diverse adolescents, ranging in age from 14 to 17, in Southern California. Neurocognitive control processes were assessed with the Iowa Gambling Task, a generic Go/No-Go task, and a food-specific Go/No-Go task. The food-specific Go/No-Go task directly ties the task to food cues that trigger responses, addressing an integral link between cue-habit processes. Dietary measures were assessed with self-administered food frequency and binge eating questionnaires. Results of latent variable models revealed marked gender differences. Inhibitory problems on the food-specific and generic Go/No-Go tasks were significantly correlated with binge eating only in females, whereas inhibitory problems measured with these tasks were the strongest correlates of sweet snack consumption in males. Higher BMI percentile and sedentary behavior also predicted binge eating in females and sweet snack consumption in males. Inhibitory problems on the generic Go/No-Go, poorer affective decision-making, assessed with the Iowa Gambling Task, and sedentary behavior were associated with sweetened beverage consumption in males, but not females. The food-specific Go/No-Go was not predictive in models evaluating sweetened beverage consumption, providing some initial discriminant validity for the task, which consisted of sweet/fatty snacks as no-go signals and no sugar-sweetened beverage signals. This research extends other study findings, revealing gender differences in inhibitory function relevant to behavioral control. Further, the findings contribute to research implicating the relevance of cues in

  10. Genetic controls balancing excitatory and inhibitory synaptogenesis in neurodevelopmental disorder models

    Directory of Open Access Journals (Sweden)

    Cheryl L Gatto

    2010-06-01

    Full Text Available Proper brain function requires stringent balance of excitatory and inhibitory synapse formation during neural circuit assembly. Mutation of genes that normally sculpt and maintain this balance results in severe dysfunction, causing neurodevelopmental disorders including autism, epilepsy and Rett syndrome. Such mutations may result in defective architectural structuring of synaptic connections, molecular assembly of synapses and/or functional synaptogenesis. The affected genes often encode synaptic components directly, but also include regulators that secondarily mediate the synthesis or assembly of synaptic proteins. The prime example is Fragile X syndrome (FXS, the leading heritable cause of both intellectual disability and autism spectrum disorders. FXS results from loss of mRNA-binding FMRP, which regulates synaptic transcript trafficking, stability and translation in activity-dependent synaptogenesis and plasticity mechanisms. Genetic models of FXS exhibit striking excitatory and inhibitory synapse imbalance, associated with impaired cognitive and social interaction behaviors. Downstream of translation control, a number of specific synaptic proteins regulate excitatory versus inhibitory synaptogenesis, independently or combinatorially, and loss of these proteins is also linked to disrupted neurodevelopment. The current effort is to define the cascade of events linking transcription, translation and the role of specific synaptic proteins in the maintenance of excitatory versus inhibitory synapses during neural circuit formation. This focus includes mechanisms that fine-tune excitation and inhibition during the refinement of functional synaptic circuits, and later modulate this balance throughout life. The use of powerful new genetic models has begun to shed light on the mechanistic bases of excitation/inhibition imbalance for a range of neurodevelopmental disease states.

  11. Acute neuropharmacological effects of atomoxetine on inhibitory control in ADHD children: A fNIRS study

    Directory of Open Access Journals (Sweden)

    Masako Nagashima

    2014-01-01

    Full Text Available The object of the current study is to explore the neural substrate for effects of atomoxetine (ATX on inhibitory control in school-aged children with attention deficit hyperactivity disorder (ADHD using functional near-infrared spectroscopy (fNIRS. We monitored the oxy-hemoglobin signal changes of sixteen ADHD children (6–14 years old performing a go/no-go task before and 1.5 h after ATX or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design. Sixteen age- and gender-matched normal controls without ATX administration were also monitored. In the control subjects, the go/no-go task recruited the right inferior and middle prefrontal gyri (IFG/MFG, and this activation was absent in pre-medicated ADHD children. The reduction of right IFG/MFG activation was acutely normalized after ATX administration but not placebo administration in ADHD children. These results are reminiscent of the neuropharmacological effects of methylphenidate to up-regulate reduced right IFG/MFG function in ADHD children during inhibitory tasks. As with methylphenidate, activation in the IFG/MFG could serve as an objective neuro-functional biomarker to indicate the effects of ATX on inhibitory control in ADHD children. This promising technique will enhance early clinical diagnosis and treatment of ADHD in children, especially in those with a hyperactivity/impulsivity phenotype.

  12. Got Rhythm? Better Inhibitory Control Is Linked with More Consistent Drumming and Enhanced Neural Tracking of the Musical Beat in Adult Percussionists and Nonpercussionists.

    Science.gov (United States)

    Slater, Jessica; Ashley, Richard; Tierney, Adam; Kraus, Nina

    2018-01-01

    Musical rhythm engages motor and reward circuitry that is important for cognitive control, and there is evidence for enhanced inhibitory control in musicians. We recently revealed an inhibitory control advantage in percussionists compared with vocalists, highlighting the potential importance of rhythmic expertise in mediating this advantage. Previous research has shown that better inhibitory control is associated with less variable performance in simple sensorimotor synchronization tasks; however, this relationship has not been examined through the lens of rhythmic expertise. We hypothesize that the development of rhythm skills strengthens inhibitory control in two ways: by fine-tuning motor networks through the precise coordination of movements "in time" and by activating reward-based mechanisms, such as predictive processing and conflict monitoring, which are involved in tracking temporal structure in music. Here, we assess adult percussionists and nonpercussionists on inhibitory control, selective attention, basic drumming skills (self-paced, paced, and continuation drumming), and cortical evoked responses to an auditory stimulus presented on versus off the beat of music. Consistent with our hypotheses, we find that better inhibitory control is correlated with more consistent drumming and enhanced neural tracking of the musical beat. Drumming variability and the neural index of beat alignment each contribute unique predictive power to a regression model, explaining 57% of variance in inhibitory control. These outcomes present the first evidence that enhanced inhibitory control in musicians may be mediated by rhythmic expertise and provide a foundation for future research investigating the potential for rhythm-based training to strengthen cognitive function.

  13. The Development of Automatic and Controlled Inhibitory Retrieval Processes in True and False Recall

    Science.gov (United States)

    Knott, Lauren M.; Howe, Mark L.; Wimmer, Marina C.; Dewhurst, Stephen A.

    2011-01-01

    In three experiments, we investigated the role of automatic and controlled inhibitory retrieval processes in true and false memory development in children and adults. Experiment 1 incorporated a directed forgetting task to examine controlled retrieval inhibition. Experiments 2 and 3 used a part-set cue and retrieval practice task to examine…

  14. Human Immunodeficiency Virus Type-1 Elite Controllers Maintain Low Co-Expression of Inhibitory Receptors on CD4+ T Cells.

    Science.gov (United States)

    Noyan, Kajsa; Nguyen, Son; Betts, Michael R; Sönnerborg, Anders; Buggert, Marcus

    2018-01-01

    Human immunodeficiency virus type-1 (HIV-1) elite controllers (ELCs) represent a unique population that control viral replication in the absence of antiretroviral therapy (cART). It is well established that expression of multiple inhibitory receptors on CD8+ T cells is associated with HIV-1 disease progression. However, whether reduced co-expression of inhibitory receptors on CD4+ T cells is linked to natural viral control and slow HIV-1 disease progression remains undefined. Here, we report on the expression pattern of numerous measurable inhibitory receptors, associated with T cell exhaustion (programmed cell death-1, CTLA-4, and TIGIT), on different CD4+ T cell memory populations in ELCs and HIV-infected subjects with or without long-term cART. We found that the co-expression pattern of inhibitory receptors was significantly reduced in ELCs compared with HIV-1 cART-treated and viremic subjects, and similar to healthy controls. Markers associated with T cell exhaustion varied among different memory CD4+ T cell subsets and highest levels were found mainly on transitional memory T cells. CD4+ T cells co-expressing all inhibitory markers were positively correlated to T cell activation (CD38+ HLA-DR+) as well as the transcription factors Helios and FoxP3. Finally, clinical parameters such as CD4 count, HIV-1 viral load, and the CD4/CD8 ratio all showed significant associations with CD4+ T cell exhaustion. We demonstrate that ELCs are able to maintain lower levels of CD4+ T cell exhaustion despite years of ongoing viral replication compared with successfully cART-treated subjects. Our findings suggest that ELCs harbor a "healthy" state of inhibitory receptor expression on CD4+ T cells that might play part in maintenance of their control status.

  15. Dissociating the role of prefrontal and premotor cortices in controlling inhibitory mechanisms during motor preparation.

    Science.gov (United States)

    Duque, Julie; Labruna, Ludovica; Verset, Sophie; Olivier, Etienne; Ivry, Richard B

    2012-01-18

    Top-down control processes are critical to select goal-directed actions in flexible environments. In humans, these processes include two inhibitory mechanisms that operate during response selection: one is involved in solving a competition between different response options, the other ensures that a selected response is initiated in a timely manner. Here, we evaluated the role of dorsal premotor cortex (PMd) and lateral prefrontal cortex (LPF) of healthy subjects in these two forms of inhibition by using an innovative transcranial magnetic stimulation (TMS) protocol combining repetitive TMS (rTMS) over PMd or LPF and a single pulse TMS (sTMS) over primary motor cortex (M1). sTMS over M1 allowed us to assess inhibitory changes in corticospinal excitability, while rTMS was used to produce transient disruption of PMd or LPF. We found that rTMS over LPF reduces inhibition associated with competition resolution, whereas rTMS over PMd decreases inhibition associated with response impulse control. These results emphasize the dissociable contributions of these two frontal regions to inhibitory control during motor preparation. The association of LPF with competition resolution is consistent with the role of this area in relatively abstract aspects of control related to goal maintenance, ensuring that the appropriate response is selected in a variable context. In contrast, the association of PMd with impulse control is consistent with the role of this area in more specific processes related to motor preparation and initiation.

  16. Dissociating the role of prefrontal and premotor cortices in controlling inhibitory mechanisms during motor preparation

    Science.gov (United States)

    Duque, Julie; Labruna, Ludovica; Verset, Sophie; Olivier, Etienne; Ivry, Richard B.

    2012-01-01

    Top-down control processes are critical to select goal-directed actions in flexible environments. In humans, these processes include two inhibitory mechanisms that operate during response selection: one is involved in solving a competition between different response options, the other ensures that a selected response is initiated timely. Here, we evaluated the role of dorsal premotor cortex (PMd) and lateral prefrontal cortex (LPF) of healthy subjects in these two forms of inhibition by using an innovative transcranial magnetic stimulation (TMS) protocol combining repetitive TMS (rTMS) over PMd or LPF and a single pulse TMS (sTMS) over primary motor cortex (M1). sTMS over M1 allowed us to assess inhibitory changes in corticospinal excitability, while rTMS was used to produce transient disruption of PMd or LPF. We found that rTMS over LPF reduces inhibition associated with competition resolution whereas rTMS over PMd decreases inhibition associated with response impulse control. These results emphasize the dissociable contributions of these two frontal regions to inhibitory control during motor preparation. The association of LPF with competition resolution is consistent with the role of this area in relatively abstract aspects of control related to goal maintenance, ensuring that the appropriate response is selected in a variable context. In contrast, the association of PMd with impulse control is consistent with the role of this area in more specific processes related to motor preparation and initiation. PMID:22262879

  17. Impaired inhibitory control in recreational cocaine users.

    Directory of Open Access Journals (Sweden)

    Lorenza S Colzato

    Full Text Available Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed.

  18. Effects of reward and punishment on brain activations associated with inhibitory control in cigarette smokers.

    Science.gov (United States)

    Luijten, Maartje; O'Connor, David A; Rossiter, Sarah; Franken, Ingmar H A; Hester, Robert

    2013-11-01

    Susceptibility to use of addictive substances may result, in part, from a greater preference for an immediate small reward relative to a larger delayed reward or relative insensitivity to punishment. This functional magnetic resonance imaging (fMRI) study examined the neural basis of inhibiting an immediately rewarding stimulus to obtain a larger delayed reward in smokers. We also investigated whether punishment could modulate inhibitory control. The Monetary Incentive Go/NoGo (MI-Go/NoGo) task was administered that provided three types of reward outcomes contingent upon inhibitory control performance over rewarding stimuli: inhibition failure was either followed by no monetary reward (neutral condition), a small monetary reward with immediate feedback (reward condition) or immediate monetary punishment (punishment condition). In the reward and punishment conditions, successful inhibitory control resulted in larger delayed rewards. Community sample of smokers in the Melbourne (Australia) area. Nineteen smokers were compared with 17 demographically matched non-smoking controls. Accuracy, reaction times and brain activation associated with the MI-Go/NoGo task. Smokers showed hyperactivation in the right insula (P rewarding stimulus to obtain a larger delayed reward, and during inhibition of neutral stimuli. Group differences in brain activity were not significant in the punishment condition in the right insula and dorsolateral prefrontal cortex, most probably as a result of increased activation in non-smoking controls. Compared with non-smokers, smokers showed increased neural activation when resisting immediately rewarding stimuli and may be less sensitive to punishment as a strategy to increase control over rewarding stimuli. © 2013 Society for the Study of Addiction.

  19. Distinguishing stimulus and response codes in theta oscillations in prefrontal areas during inhibitory control of automated responses.

    Science.gov (United States)

    Mückschel, Moritz; Dippel, Gabriel; Beste, Christian

    2017-11-01

    Response inhibition mechanisms are mediated via cortical and subcortical networks. At the cortical level, the superior frontal gyrus, including the supplementary motor area (SMA) and inferior frontal areas, is important. There is an ongoing debate about the functional roles of these structures during response inhibition as it is unclear whether these structures process different codes or contents of information during response inhibition. In the current study, we examined this question with a focus on theta frequency oscillations during response inhibition processes. We used a standard Go/Nogo task in a sample of human participants and combined different EEG signal decomposition methods with EEG beamforming approaches. The results suggest that stimulus coding during inhibitory control is attained by oscillations in the upper theta frequency band (∼7 Hz). In contrast, response selection codes during inhibitory control appear to be attained by the lower theta frequency band (∼4 Hz). Importantly, these different codes seem to be processed in distinct functional neuroanatomical structures. Although the SMA may process stimulus codes and response selection codes, the inferior frontal cortex may selectively process response selection codes during inhibitory control. Taken together, the results suggest that different entities within the functional neuroanatomical network associated with response inhibition mechanisms process different kinds of codes during inhibitory control. These codes seem to be reflected by different oscillations within the theta frequency band. Hum Brain Mapp 38:5681-5690, 2017. © 2017 Wiley-Liss, Inc. © 2017 Wiley Periodicals, Inc.

  20. Childhood inhibitory control and adolescent impulsivity and novelty seeking as differential predictors of relational and overt aggression.

    Science.gov (United States)

    Sarkisian, Katherine; Van Hulle, Carol; Lemery-Chalfant, Kathryn; Goldsmith, H H

    2017-04-01

    Impulsivity is commonly conflated with novelty seeking, but these traits are conceptually independent and hold different predictive implications. Using a multi-informant, longitudinal design, we examined childhood inhibitory control, as well as adolescent impulsivity and novelty seeking, as predictors of aggression in a sample of 976 twins. Lower childhood inhibitory control and higher adolescent impulsivity predicted both overt and relational aggression in regression analyses that accounted for sex, puberty status, age, and socioeconomic status. As predicted, novelty seeking did not predict aggression, a finding that supports its independence from impulsivity.

  1. Obesity is associated with lack of inhibitory control and impaired heart rate variability reactivity and recovery in response to food stimuli.

    Science.gov (United States)

    Spitoni, Grazia Fernanda; Ottaviani, Cristina; Petta, Anna Maria; Zingaretti, Pietro; Aragona, Massimiliano; Sarnicola, Antonio; Antonucci, Gabriella

    2017-06-01

    Recent theories compare obesity with addiction in terms of lack of inhibitory control in both clinical populations. The present study hypothesized impaired inhibition in obese patients reflected both in executive functions and reduced vagal tone (indexed by a decrease in heart rate variability; HRV) in response to food stimuli. Twenty-four inpatients with obesity (19 women) and 37 controls (24 women) underwent ECG monitoring during baseline, food stimuli viewing, and a recovery phase. Tests and questionnaires assessing inhibitory control and psychopathological dispositions were also administered. As hypothesized, patients were characterized by deficits in all the tests measuring inhibitory capacities. Results also show greater HRV reduction and impaired HRV recovery in response to food stimuli in obese patients compared to controls. The drive to eat experienced by obese patients in the absence of caloric need may rely on impairments in inhibitory and vagal functioning. Results are discussed in terms of implications for therapy. Copyright © 2017. Published by Elsevier B.V.

  2. Romantic love is associated with enhanced inhibitory control in an emotional stop-signal task

    Directory of Open Access Journals (Sweden)

    Sensen Song

    2016-10-01

    Full Text Available Purpose: This study explored whether romantic lovers differ in emotion-related inhibitory control capacity from those who are single. Methods: 88 healthy undergraduate college students participated in the study. Half were currently in love and in a romantic relationship (love group, LG, and half were single and had never been in a romantic relationship (single group, SG. Based on duration of romantic relationship (i.e., love duration, the LG were further divided into two subgroups: early stage love and longer periods of love. All participants completed an emotional Stop Signal Task (eSST, which consisted of a variety of human face stimuli representing sadness (a negative emotion, as well as neutral emotions. Results: Results found that relative to SG, lovers showed greater inhibitory control [shorter stop-signal reaction time (SSRT] during negative emotion condition trials. Furthermore, in early stages of love, SSRT for negative emotion condition trials was significantly shorter compared to that in longer periods of love or SG individuals, with no significant differences between the latter two groups. Conclusions: Compared with individuals who were single, early-stage lovers showed greater capacity for inhibiting action during presentation of negative emotional stimuli. Within a greater social context, greater inhibitory control capacity during early stages of love may be related to the successful formation of romantic relationships, particularly to the ability to persevere in goal-directed action despite negative emotional contexts such as that of sadness.

  3. Romantic Love Is Associated with Enhanced Inhibitory Control in an Emotional Stop-Signal Task

    Science.gov (United States)

    Song, Sensen; Zou, Zhiling; Song, Hongwen; Wang, Yongming; d’Oleire Uquillas, Federico; Wang, Huijun; Chen, Hong

    2016-01-01

    Purpose: This study explored whether romantic lovers differ in emotion-related inhibitory control capacity from those who are single. Methods: 88 healthy undergraduate college students participated in the study. Half were currently in love and in a romantic relationship (love group, LG), and half were single and had never been in a romantic relationship (single group, SG). Based on duration of romantic relationship (i.e., love duration), the LG were further divided into two subgroups: “early stage love” and “longer periods of love”. All participants completed an emotional Stop Signal Task, consisting of a variety of human face stimuli displaying either sad or neutral affect. Results: Results found that relative to SG, lovers showed greater inhibitory control [shorter stop-signal reaction time (SSRT)] during negative emotion condition trials. Furthermore, in early stages of love, SSRT for negative emotion condition trials was significantly shorter compared to that in “longer periods of love” or SG individuals, with no significant differences between the two latter groups. Conclusion: Compared with individuals who were single, early stage lovers showed greater capacity for inhibiting action during presentation of negative emotional stimuli. Within a greater social context, greater inhibitory control capacity during early stages of love may be related to the successful formation of romantic relationships, particularly to the ability to persevere in goal-directed action despite negative emotional contexts such as that of sadness. PMID:27826260

  4. Dinitrosyl iron complexes with thiolate ligands: physico-chemistry, biochemistry and physiology.

    Science.gov (United States)

    Vanin, Anatoly F

    2009-08-01

    Some present-day concepts on the origin and functional activities of dinitrosyl iron complexes (DNIC) with thiolate ligands are considered. Nitric oxide (NO) including to DNIC increases its stability and ensures effective targeting of NO to organs and tissues. DNIC have a square-planar structure; unpaired electron is localized on the d(z2) orbital of the d(7) iron atom. The formula of DNIC appears as [(RS(-))(2)Fe(+)(NO(+))(2)....((-)SR)(2)](-); electron spin is S=1/2. Conversion of an originally diamagnetic group, Fe(2+)(NO)(2) with electron configuration d(8), into a paramagnetic Fe(+)(NO(+))(2) group is a result of disproportionation of NO ligands and substitution of newly generated NO(-) for NO. The nitrosonium ions present in DNIC impart to them high nitrosylating activity, e.g., ability to induce S-nitrosylation of thiols. The ability of S-nitrosothiols to form DNIC in a direct reaction with bivalent iron is a prerequisite to effective mutual conversions of DNIC and S-nitrosothiols. In this work, I consider some mechanisms of destructive effects of low-molecular DNIC on active centers of iron-sulfur proteins, ability of DNIC to express certain genes, to activate guanylate cyclase, to exert hypotensive, vasodilator effects, to inhibit platelet aggregation, to accelerate wound healing and to produce potent erective action. Recently a stabilized powder-like polymeric composition based on dimeric glutathione DNIC the water-soluble polymer in which was used as a filling agent was designed. The advantages of this stable DNIC-glutathione preparation include their ability to retain their physico-chemical and functional activities within at least one year. At present, the preparation undergo testing as a base for the design of a wide variety of broad-spectrum drugs.

  5. [Dinitrosyl iron complexes with glutathione recover rats with experimental endometriosis].

    Science.gov (United States)

    Adamian, L V; Burgova, E N; Tkachev, N A; Mikoian, V D; Stepanian, A A; Sonova, M M; Vanin, A F

    2013-01-01

    The effect of binuclear dinitrosyl iron complexes (DNIC) with glutathione on endometrioid tumors in rats with experimental endometriosis has been studied. The latter was induced by an autotransplantation model, where two fragments of endometrium with myometrium (2 x 2 mm) from the left uterine horn was grafted to the inner surface of the anterior abdominal wall. The test animals received intraperitoneal injections of 0.5 ml DNIC-glutathione at the dose of 12.5 micromole per kg daily for 12 days 28 days after operation. The injections resulted in more than a 2-fold decrease in the total volume of both large tumors formed from grafts and small additive tumors formed nearby grafts. The disappearance of the additive tumors was also observed in test animals. The EPR signal with g(av) = 2.03 characteristic of protein bound DNIC with thiol-containing ligands was recorded in livers, graft and additive tumors of test and control animals pointing out intensive generation of nitric oxide in rats with experimental endometriosis. Ribonucleotide reductase activation discovered by doublet the EPR signal at g = 2.0 with 2.3 mT hyperfine structure splitting was found in small tumors. The cytotoxic effect of DNIC-glutathione on endometrioid tumors was suggested to be due to DNIC degradation nearby the tumors induced by iron chelating compounds released from the tumors. The degradation resulted in release of a high amount of nitric oxide molecules and nitrosonium ions from DNICs affecting the tumors by way of the cytotoxic effect.

  6. Do daily fluctuations in inhibitory control predict alcohol consumption? : An ecological momentary assessment study

    NARCIS (Netherlands)

    Jones, Andrew; Tiplady, Brian; Houben, Katrijn; Nederkoorn, Chantal; Field, Matt

    RATIONALE: Deficient inhibitory control is predictive of increased alcohol consumption in the laboratory; however, little is known about this relationship in naturalistic, real-world settings. OBJECTIVES: In the present study, we implemented ecological momentary assessment methods to investigate the

  7. Dinitrosyl iron complexes with glutathione as NO and NO⁺ donors.

    Science.gov (United States)

    Borodulin, Rostislav R; Kubrina, Lyudmila N; Mikoyan, Vasak D; Poltorakov, Alexander P; Shvydkiy, Vyacheslav О; Burbaev, Dosymzhan Sh; Serezhenkov, Vladimir A; Yakhontova, Elena R; Vanin, Anatoly F

    2013-02-28

    It has been found that heating of solutions of the binuclear form of dinitrosyl iron complexes (B-DNIC) with glutathione in a degassed Thunberg apparatus (рН 1.0, 70°С, 6 h) results in their decomposition with a concomitant release of four gaseous NO molecules per one B-DNIC. Further injection of air into the Thunberg apparatus initiates fast oxidation of NO to NO₂ and formation of two GS-NO molecules per one B-DNIC. Under similar conditions, the decomposition of B-DNIC solutions in the Thunberg apparatus in the presence of air is complete within 30-40 min and is accompanied by formation of four GS-NO molecules per one B-DNIC. It is suggested that the latter events are determined by oxidation of B-DNIC iron and concominant release of four nitrosonium ions (NO⁺) from each complex. Binding of NO⁺ to thiol groups of glutathione provokes GS-NO synthesis. At neutral рН, decomposition of B-DNIC is initiated by strong iron chelators, viz., о-phenanthroline and N-methyl-d-glucamine dithiocarbamate (MGD). In the former case, the reaction occurs under anaerobic conditions (degassed Thunberg apparatus) and is accompanied by a release of four NO molecules from B-DNIC. Under identical conditions, MGD-induced decomposition of B-DNIC gives two EPR-active mononuclear mononitrosyl iron complexes with MGD (MNIC-MGD) able to incorporate two iron molecules and two NO molecules from each B-DNIC. The other two NO molecules released from B-DNIC (most probably, in the form of nitrosonium ions) bind to thiol groups of MGD to give corresponding S-nitrosothiols. Acidification of test solutions to рН 1.0 initiates hydrolysis of MGD and, as a consequence, decomposition of MNIC-MGD and the S-nitrosated form of MGD; the gaseous phase contains four NO molecules (as calculated per each B-DNIC). The data obtained testify to the ability of B-DNIC with glutathione (and, probably, of B-DNIC with other thiol-containing ligands) to release both NO molecules and nitrosonium ions upon their

  8. Influence of inhibitory control on planning abilities in children with mild intellectual disability

    Directory of Open Access Journals (Sweden)

    Gligorović Milica

    2016-01-01

    Full Text Available With regard to the fact that the tendency toward unsophisticated strategies is often related to difficulties with basic components of executive functions, the aim of this research was to determine the relation between planning abilities and inhibitory control in children with mild intellectual disability (MID. The sample included 56 children with idiopathic MID (IQ 50-69, M=61.13, SD=7.14, of both genders (26/46.3% of girls, between 9.11 and 14.03 years of age (M=11.61; SD=1.29. Go no Go Task and Day/Night Stroop Task were used for the assessment of inhibitory control (delayed response to the agreed signal, conflict provoking motor responses, and inhibition of arrogant verbal responses, while Tower of London Test (ToL was used for the assessment of planning abilities. Multivariate analysis of covariance (MANCOVA, paired samples t-test, Pearson's correlation, and partial correlation coefficients were used in statistical analysis of the results. The results showed that the mistakes in Response delay set of Go-no-Go task were the only significant factor of primary Total move score variable (ToL. The influence of the ability to delay motor activity, assessed by Response delay set, on all ToL variables was statistically significant (p=0.003. The results lead to a conclusion that, during the processes of planning and executing activities, children with MID primarily rely on simple inhibitory mechanisms.

  9. Macrophage migration inhibitory factor as an incriminating agent in vitiligo.

    Science.gov (United States)

    Farag, Azza Gaber Antar; Hammam, Mostafa Ahmed; Habib, Mona SalahEldeen; Elnaidany, Nada Farag; Kamh, Mona Eaid

    2018-03-01

    Vitiligo is an autoimmune skin disorder in which the loss of melanocytes is mainly attributed to defective autoimmune mechanisms and, lately, there has been more emphasis on autoinflammatory mediators. Among these is the macrophage migration inhibitory factor, which is involved in many autoimmune skin diseases. However, little is known about the contribution of this factor to vitiligo vulgaris. To determine the hypothesized role of migration inhibitory factor in vitiligo via estimation of serum migration inhibitory factor levels and migration inhibitory factor mRNA concentrations in patients with vitiligo compared with healthy controls. We also aimed to assess whether there is a relationship between the values of serum migration inhibitory factor and/or migration inhibitory factor mRNA with disease duration, clinical type and severity in vitiligo patients. Evaluation of migration inhibitory factor serum level and migration inhibitory factor mRNA expression by ELISA and real-time PCR, respectively, were performed for 50 patients with different degrees of vitiligo severity and compared to 15 age- and gender-matched healthy volunteers as controls. There was a highly significant increase in serum migration inhibitory factor and migration inhibitory factor mRNA levels in vitiligo cases when compared to controls (pvitiligo patients, and each of them with duration and severity of vitiligo. In addition, patients with generalized vitiligo have significantly elevated serum migration inhibitory factor and mRNA levels than control subjects. Small number of investigated subjects. Migration inhibitory factor may have an active role in the development of vitiligo, and it may also be a useful index of disease severity. Consequently, migration inhibitory factor may be a new treatment target for vitiligo patients.

  10. General deficit in inhibitory control of excessive smartphone users: Evidence from an event-related potential study

    Directory of Open Access Journals (Sweden)

    Jingwei eChen

    2016-04-01

    Full Text Available With the popularity of smartphones, the problem of excessive use has drawn increasing attention. However, it is not clear whether there is an inhibitory deficit in excessive smartphone users. Using a modified Go/NoGo task with three types of context (blank, neutral and smartphone-related, the present study combined measures of behavior and electrophysiology (event-related potentials, ERPs to examine general and specific inhibitory control in an excessive smartphone use group and a normal use group. Results showed that participants in both groups had larger amplitude of N2 and P3 on NoGo trials than Go trials. NoGo N2, an ERP component associated with inhibitory control, was more negative in the excessive smartphone use group than the normal use group. These results suggest that in the early stage of inhibition processing, excessive smartphone users experience more conflicts and show a general deficit that does not depend on smartphone-related cues. Moreover, the study provides further neuroscience evidence of the physiological correlates of excessive smartphone use.

  11. General Deficit in Inhibitory Control of Excessive Smartphone Users: Evidence from an Event-Related Potential Study

    Science.gov (United States)

    Chen, Jingwei; Liang, Yunsi; Mai, Chunmiao; Zhong, Xiyun; Qu, Chen

    2016-01-01

    With the popularity of smartphones, the problem of excessive use has drawn increasing attention. However, it is not clear whether there is an inhibitory deficit in excessive smartphone users. Using a modified Go/NoGo task with three types of context (blank, neutral, and smartphone-related), the present study combined measures of behavior and electrophysiology [event-related potentials (ERPs)] to examine general and specific inhibitory control in an excessive smartphone use group and a normal use group. Results showed that participants in both groups had larger amplitude of N2 and P3 on NoGo trials than Go trials. NoGo N2, an ERP component associated with inhibitory control, was more negative in the excessive smartphone use group than the normal use group. These results suggest that in the early stage of inhibition processing, excessive smartphone users experience more conflicts and show a general deficit that does not depend on smartphone-related cues. Moreover, the study provides further neuroscience evidence of the physiological correlates of excessive smartphone use. PMID:27148120

  12. Brief report: Inhibitory control of socially relevant stimuli in children with high functioning autism

    NARCIS (Netherlands)

    Geurts, H.M.; Begeer, S.; Stockman, L.

    2009-01-01

    The current study explored whether inhibitory control deficits in high functioning autism (HFA) emerged when socially relevant stimuli were used and whether arousal level affected the performance. A Go/NoGo paradigm, with socially relevant stimuli and varying presentation rates, was applied in 18

  13. Behavioral inhibition and anxiety: The moderating roles of inhibitory control and attention shifting

    Science.gov (United States)

    White, Lauren K.; McDermott, Jennifer Martin; Degnan, Kathryn A.; Henderson, Heather A.; Fox, Nathan A.

    2013-01-01

    Behavioral inhibition (BI), a temperament identified in early childhood, is associated with social reticence in childhood and an increased risk for anxiety problems in adolescence and adulthood. However, not all behaviorally inhibited children remain reticent or develop an anxiety disorder. One possible mechanism accounting for the variability in the developmental trajectories of BI is a child’s ability to successfully recruit cognitive processes involved in the regulation of negative reactivity. However, separate cognitive processes may differentially moderate the association between BI and later anxiety problems. The goal of the current study was to examine how two cognitive processes - attention shifting and inhibitory control - laboratory assessed at 48 months of age moderated the association between 24-month BI and anxiety symptoms in the preschool years. Results revealed that high levels of attention shifting decreased the risk for anxiety symptoms in children with high levels of BI, whereas high levels of inhibitory control increased this risk for anxiety symptoms. These findings suggest that different cognitive processes may influence relative levels of risk or adaptation depending upon a child’s temperamental reactivity. PMID:21301953

  14. Neural correlates of atomoxetine improving inhibitory control and visual processing in Drug-naïve adults with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Fan, Li-Ying; Chou, Tai-Li; Gau, Susan Shur-Fen

    2017-10-01

    Atomoxetine improves inhibitory control and visual processing in healthy volunteers and adults with attention-deficit/hyperactivity disorder (ADHD). However, little is known about the neural correlates of these two functions after chronic treatment with atomoxetine. This study aimed to use the counting Stroop task with functional magnetic resonance imaging (fMRI) and the Cambridge Neuropsychological Test Automated Battery (CANTAB) to investigate the changes related to inhibitory control and visual processing in adults with ADHD. This study is an 8-week, placebo-controlled, double-blind, randomized clinical trial of atomoxetine in 24 drug-naïve adults with ADHD. We investigated the changes of treatment with atomoxetine compared to placebo-treated counterparts using the counting Stroop fMRI and two CANTAB tests: rapid visual information processing (RVP) for inhibitory control and delayed matching to sample (DMS) for visual processing. Atomoxetine decreased activations in the right inferior frontal gyrus and anterior cingulate cortex, which were correlated with the improvement in inhibitory control assessed by the RVP. Also, atomoxetine increased activation in the left precuneus, which was correlated with the improvement in the mean latency of correct responses assessed by the DMS. Moreover, anterior cingulate activation in the pre-treatment was able to predict the improvements of clinical symptoms. Treatment with atomoxetine may improve inhibitory control to suppress interference and may enhance the visual processing to process numbers. In addition, the anterior cingulate cortex might play an important role as a biological marker for the treatment effectiveness of atomoxetine. Hum Brain Mapp 38:4850-4864, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Dose-response relationships between exercise intensity, cravings, and inhibitory control in methamphetamine dependence: An ERPs study.

    Science.gov (United States)

    Wang, Dongshi; Zhou, Chenglin; Zhao, Min; Wu, Xueping; Chang, Yu-Kai

    2016-04-01

    The present study integrated behavioral and neuroelectric approaches for determining the dose-response relationships between exercise intensity and methamphetamine (MA) craving and between exercise intensity and inhibitory control in individuals with MA dependence. Ninety-two individuals with MA dependence were randomly assigned to an exercise group (light, moderate, or vigorous intensity) or to a reading control group. The participants then completed a craving self-report at four time points: before exercise, during exercise, immediately after exercise, and 50 min after exercise. Event-related potentials were also recorded while the participants completed a standard Go/NoGo task and an MA-related Go/NoGo task approximately 20 min after exercise cessation. The reduction in self-reported MA craving scores of the moderate and vigorous intensity groups was greater than that of the light intensity and control groups during acute exercise as well as immediately and 50 min following exercise termination. Additionally, an inverted-U-shaped relationship between exercise intensity and inhibitory control was generally observed for the behavioral and neuroelectric indices, with the moderate intensity group exhibiting shorter Go reaction times, increased NoGo accuracy, and larger NoGo-N2 amplitudes. Acute exercise may provide benefits for MA-associated craving and inhibitory control in MA-dependent individuals, as revealed by behavioral and neuroelectric measures. Moderate-intensity exercise may be associated with more positive effects, providing preliminary evidence for the establishment of an exercise prescription regarding intensity for MA dependence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Nitrosothiol Formation and Protection against Fenton Chemistry by Nitric Oxide-induced Dinitrosyliron Complex Formation from Anoxia-initiated Cellular Chelatable Iron Increase*

    Science.gov (United States)

    Li, Qian; Li, Chuanyu; Mahtani, Harry K.; Du, Jian; Patel, Aashka R.; Lancaster, Jack R.

    2014-01-01

    Dinitrosyliron complexes (DNIC) have been found in a variety of pathological settings associated with •NO. However, the iron source of cellular DNIC is unknown. Previous studies on this question using prolonged •NO exposure could be misleading due to the movement of intracellular iron among different sources. We here report that brief •NO exposure results in only barely detectable DNIC, but levels increase dramatically after 1–2 h of anoxia. This increase is similar quantitatively and temporally with increases in the chelatable iron, and brief •NO treatment prevents detection of this anoxia-induced increased chelatable iron by deferoxamine. DNIC formation is so rapid that it is limited by the availability of •NO and chelatable iron. We utilize this ability to selectively manipulate cellular chelatable iron levels and provide evidence for two cellular functions of endogenous DNIC formation, protection against anoxia-induced reactive oxygen chemistry from the Fenton reaction and formation by transnitrosation of protein nitrosothiols (RSNO). The levels of RSNO under these high chelatable iron levels are comparable with DNIC levels and suggest that under these conditions, both DNIC and RSNO are the most abundant cellular adducts of •NO. PMID:24891512

  17. An event-related potential investigation of the acute effects of aerobic and coordinative exercise on inhibitory control in children with ADHD

    Directory of Open Access Journals (Sweden)

    Sebastian Ludyga

    2017-12-01

    Full Text Available The current body of evidence suggests that an aerobic exercise session has a beneficial effect on inhibitory control, whereas the impact of coordinative exercise on this executive function has not yet been examined in children with ADHD. Therefore, the present study aims to investigate the acute effects of aerobic and coordinative exercise on behavioral performance and the allocation of attentional resources in an inhibitory control task.Using a cross-over design, children with ADHD-combined type and healthy comparisons completed a Flanker task before and after 20 min moderately-intense cycling exercise, coordinative exercise and an inactive control condition. During the task, stimulus-locked event-related potentials were recorded with electroencephalography.Both groups showed an increase of P300 amplitude and decrease of reaction time after exercise compared to the control condition. Investigating the effect of exercise modality, aerobic exercise led to greater increases of P300 amplitude and reductions in reaction time than coordinative exercise in children with ADHD.The findings suggest that a single exercise bout improves inhibitory control and the allocation of attentional resources. There were some indications that an aerobic exercise session seems to be more efficient than coordinative exercise in reducing the inhibitory control deficits that persist in children with ADHD. Keywords: P300, Executive function, Cognitive performance, Flanker task, Development, Healthy children

  18. Theoretical Investigations on the Mechanistic Aspects of O2 Activation by a Biomimetic Dinitrosyl Iron Complex

    NARCIS (Netherlands)

    Banerjee, Ambar; Sen, Souloke; Paul, Ankan

    2018-01-01

    Though dinitrosyl-iron complexes (DNICs) are largely believed to act as NO carriers, several experiments on model DNICs have suggested that they can also act as nitrating agents in presence of dioxygen. Oxygen activation by DNICs has been implicated as a possible route for protein tyrosine nitration

  19. The Role of Inhibitory Control in Children's Cooperative Behaviors during a Structured Puzzle Task

    Science.gov (United States)

    Giannotta, Fabrizia; Burk, William J.; Ciairano, Silvia

    2011-01-01

    This study examined the role of inhibitory control (measured by Stroop interference) in children's cooperative behaviors during a structured puzzle task. The sample consisted of 250 8-, 10-, and 12-year-olds (117 girls and 133 boys) attending classrooms in three primary schools in Northern Italy. Children individually completed an elaborated…

  20. Inhibitory Control and Harsh Discipline as Predictors of Externalizing Problems in Young Children: A Comparative Study of U.S., Chinese, and Japanese Preschoolers

    Science.gov (United States)

    Olson, Sheryl L.; Tardif, Twila Z.; Miller, Alison; Felt, Barbara; Grabell, Adam S.; Kessler, Daniel; Wang, Li; Karasawa, Mayumi; Hirabayashi, Hidemi

    2011-01-01

    We examined associations between child inhibitory control, harsh parental discipline and externalizing problems in 120 4 year-old boys and girls in the US, China, and Japan. Individual differences in children's inhibitory control abilities, assessed using behavioral tasks and maternal ratings, were related to child externalizing problems reported…

  1. Inhibitory control effects in adolescent binge eating and consumption of sugar-sweetened beverages and snacks

    OpenAIRE

    Ames, Susan L.; Kisbu-Sakarya, Yasemin; Reynolds, Kim D.; Boyle, Sarah; Cappelli, Christopher; Cox, Matthew G.; Dust, Mark; Grenard, Jerry L.; Mackinnon, David P.; Stacy, Alan W.

    2014-01-01

    Inhibitory control and sensitivity to reward are relevant to the food choices individuals make frequently. An imbalance of these systems can lead to deficits in decision-making that are relevant to food ingestion. This study evaluated the relationship between dietary behaviors – binge eating and consumption of sweetened beverages and snacks - and behavioral control processes, among 198 ethnically diverse adolescents, ranging in age from 14 to 17, in Southern California. Neurocognitive control...

  2. College Binge Drinking Associated with Decreased Frontal Activation to Negative Emotional Distractors during Inhibitory Control

    Directory of Open Access Journals (Sweden)

    Julia E. Cohen-Gilbert

    2017-09-01

    Full Text Available The transition to college is associated with an increase in heavy episodic alcohol use, or binge drinking, during a time when the prefrontal cortex and prefrontal-limbic circuitry continue to mature. Traits associated with this immaturity, including impulsivity in emotional contexts, may contribute to risky and heavy episodic alcohol consumption. The current study used blood oxygen level dependent (BOLD multiband functional magnetic resonance imaging (fMRI to assess brain activation during a task that required participants to ignore background images with positive, negative, or neutral emotional valence while performing an inhibitory control task (Go-NoGo. Subjects were 23 college freshmen (seven male, 18–20 years who engaged in a range of drinking behavior (past 3 months’ binge episodes range = 0–19, mean = 4.6, total drinks consumed range = 0–104, mean = 32.0. Brain activation on inhibitory trials (NoGo was contrasted between negative and neutral conditions and between positive and neutral conditions using non-parametric testing (5000 permutations and cluster-based thresholding (z = 2.3, p ≤ 0.05 corrected. Results showed that a higher recent incidence of binge drinking was significantly associated with decreased activation of dorsolateral prefrontal cortex (DLPFC, dorsomedial prefrontal cortex (DMPFC, and anterior cingulate cortex (ACC, brain regions strongly implicated in executive functioning, during negative relative to neutral inhibitory trials. No significant associations between binge drinking and brain activation were observed for positive relative to neutral images. While task performance was not significantly associated with binge drinking in this sample, subjects with heavier recent binge drinking showed decreased recruitment of executive control regions under negative versus neutral distractor conditions. These findings suggest that in young adults with heavier recent binge drinking, processing of negative emotional

  3. Attention Problems, Inhibitory Control, and Intelligence Index Overlapping Genetic Factors: A Study in 9-, 12-, and 18-Year-Old Twins

    OpenAIRE

    Polderman, T.J.C.; de Geus, E.J.C.; Hoekstra, R.A.; Bartels, M.; van Leeuwen, M.; Verhulst, F.C.; Posthuma, D.; Boomsma, D.I.

    2009-01-01

    It is assumed that attention problems (AP) are related to impaired executive functioning. We investigated the association between AP and inhibitory control and tested to what extent the association was due to genetic factors shared with IQ. Data were available from 3 independent samples of 9-, 12-, and 18-year-old twins and their siblings (1,209 participants). AP were assessed with checklists completed by multiple informants. Inhibitory control was measured with the Stroop Color Word Task (St...

  4. Adolescents with and without gestational cocaine exposure: Longitudinal analysis of inhibitory control, memory and receptive language.

    Science.gov (United States)

    Betancourt, Laura M; Yang, Wei; Brodsky, Nancy L; Gallagher, Paul R; Malmud, Elsa K; Giannetta, Joan M; Farah, Martha J; Hurt, Hallam

    2011-01-01

    Preclinical studies of gestational cocaine exposure (GCE) show evidence of changes in brain function at the anatomical, physiological, and behavioral levels, to include effects on developing dopaminergic systems. In contrast, human studies have produced less consistent results, with most showing small effects or no effects on developmental outcomes. Important changes in brain structure and function occur through adolescence, therefore it is possible that prenatal cocaine exposure has latent effects on neurocognitive (NC) outcome that do not manifest until adolescence or young adulthood. We examined NC function using a set of 5 tasks designed to tap 4 different systems: inhibitory control, working memory, receptive language, and incidental memory. For each NC task, data were collected longitudinally at ages 12, 14.5 and 17 years and examined using generalized estimating equations. One hundred and nine children completed at least two of the three evaluations. Covariates included in the final model were assessment number, gender, participant age at first assessment, caregiver depression, and two composites from the Home Observation for Measurement of the Environment (HOME), Environmental Stimulation and Parental Nurturance. We found no cocaine effects on inhibitory control, working memory, or receptive language (p=0.18). GCE effects were observed on incidental face memory task (p=0.055), and GCE by assessment number interaction effects were seen on the incidental word memory task (p=0.031). Participant performance on inhibitory control, working memory, and receptive language tasks improved over time. HOME Environmental Stimulation composite was associated with better receptive language functioning. With a larger sample size smaller differences between groups may have been detected. This report shows no evidence of latent effects of GCE on inhibitory control, working memory, or receptive language. GCE effects were observed on the incidental face memory task, and GCE by

  5. Modulation of Apoptosis Controls Inhibitory Interneuron Number in the Cortex

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    Myrto Denaxa

    2018-02-01

    Full Text Available Cortical networks are composed of excitatory projection neurons and inhibitory interneurons. Finding the right balance between the two is important for controlling overall cortical excitation and network dynamics. However, it is unclear how the correct number of cortical interneurons (CIs is established in the mammalian forebrain. CIs are generated in excess from basal forebrain progenitors, and their final numbers are adjusted via an intrinsically determined program of apoptosis that takes place during an early postnatal window. Here, we provide evidence that the extent of CI apoptosis during this critical period is plastic and cell-type specific and can be reduced in a cell-autonomous manner by acute increases in neuronal activity. We propose that the physiological state of the emerging neural network controls the activity levels of local CIs to modulate their numbers in a homeostatic manner.

  6. Theory of Mind, Inhibitory Control, and Preschool-Age Children's Suggestibility in Different Interviewing Contexts

    Science.gov (United States)

    Scullin, Matthew H.; Bonner, Karri

    2006-01-01

    The current study examined the relations among 3- to 5-year-olds' theory of mind, inhibitory control, and three measures of suggestibility: yielding to suggestive questions (yield), shifting answers in response to negative feedback (shift), and accuracy in response to misleading questions during a pressured interview about a live event. Theory of…

  7. Inhibitory Control Mediates the Relationship between Depressed Mood and Overgeneral Memory Recall in Children

    Science.gov (United States)

    Raes, Filip; Verstraeten, Katrien; Bijttebier, Patricia; Vasey, Michael W.; Dalgleish, Tim

    2010-01-01

    It has been well established that depressed mood is related to overgeneral memory recall (OGM), which refers to a relative difficulty in retrieving specific information from one's autobiographical memory (AM). The present study examined whether OGM is also related to depressed mood in children and whether lack of inhibitory control mediates this…

  8. Inhibitory control as a factor of adaptive functioning of children with mild intellectual disability

    Directory of Open Access Journals (Sweden)

    Gligorović Milica

    2012-01-01

    Full Text Available Bearing in mind that the adaptive behaviour is one of the defining parameters of intellectual disability, determining of the influence of inhibitory control on adaptive functioning in children with mild intellectual disability was defined as a basic aim of this research. The sample covered 95 children with mild intellectual disability (MID, of both genders, from 10 to 14 years of age. By analysis of the data of schools' pedagogical-psychological departments, data on age and intellectual abilities of participants were collected. Inhibitory control was estimated by Go no Go task, consisted of Conflict Response and Response Delay sets. Adaptive skills data were gained on the basis of a standardized interview with special education teachers, by applying of AAMR Scale of adaptive functioning. On the basis of factor analysis, Scale scores were grouped in five factors: Personal independence, Social Independence, Personal and Social Responsibility, Social Adaptability and Personal Adaptability. Significance of relations among the observed variables was established by Pearson's correlation coefficient, by partial correlation coefficient and multifactorial variance analysis. Based on the analysis of results a statistically significant relationship between errors in the execution of tasks that belong to the set of conflict motor responses and adaptive functioning (p≤0.000 was established. The relationship between errors that belong to the set of the response delay, and adaptive functioning is not statistically significant (p=0.324. Inhibition of the interference response is a significant factor of practical (partial η2=0.227, conceptual (partial η2=0.341 and social (partial η2=0.131 adaptive skills, while the response delay is significantly associated with the conceptual skills (p=0.029 only. Inhibitory control did not prove itself a significant factor in behaviour problems of externalizing and internalized type.

  9. Maternal controlling feeding practices and girls’ inhibitory control interact to predict changes in BMI and eating in the absence of hunger from 5 to 7 y1234

    Science.gov (United States)

    Rollins, Brandi Y; Loken, Eric; Savage, Jennifer S; Birch, Leann L

    2014-01-01

    Background: Mothers use a range of feeding practices to limit children's intake of palatable snacks (eg, keeping snacks out of reach, not bringing snacks into the home), but less is known about the effects of these practices on children's eating and weight outcomes. Objective: The objective was to identify distinct feeding practice profiles and evaluate the interactive effects of these profiles and girls’ temperament (inhibitory control and approach) on girls’ eating behaviors and weight outcomes at 5 and 7 y. Design: Participants included 180 mother-daughter dyads; measures were mothers’ reports of controlling feeding practices and girls’ height and weight, eating in the absence of hunger (EAH) at 5 y, and inhibitory control (a measure of behavioral inhibition) and approach (a measure of appetitive motivation) at 7 y. Results: Latent profile analysis of maternal feeding practices showed 4 feeding profiles based on maternal use of limit-setting practices and keeping snacks out of girls’ physical reach, a restrictive practice: Unlimited Access to Snacks, Sets Limits+Does Not Restrict Snacks, Sets Limits+Restricts High Fat/Sugar Snacks, and Sets Limits+Restricts All Snacks. Girls whose mothers used Sets Limits+Restricts All Snacks had a higher approach and EAH at 5 y. Low inhibitory control girls whose mothers used Sets Limits+Restricts All Snacks or Unlimited Access to Snacks had greater increases in EAH and body mass index (BMI) from 5 to 7 y. Conclusions: Effects of maternal control on girls’ EAH and BMI may differ by the type of practice used (eg, limit-setting or restrictive practices). Girls with low inhibitory control were more susceptible to the negative effects of low and high control. PMID:24284443

  10. Two inhibitory control training interventions designed to improve eating behaviour and determine mechanisms of change.

    Science.gov (United States)

    Allom, Vanessa; Mullan, Barbara

    2015-06-01

    Inhibitory control training has been shown to influence eating behaviour in the laboratory; however, the reliability of these effects is not yet established outside the laboratory, nor are the mechanisms responsible for change in behaviour. Two online Stop-Signal Task training interventions were conducted to address these points. In Study 1, 72 participants completed baseline and follow-up measures of inhibitory control, self-regulatory depletion, fat intake and body-mass index. Participants were randomly assigned to complete one of three Stop-Signal Tasks daily for ten days: food-specific inhibition--inhibition in response to unhealthy food stimuli only, general inhibition--inhibition was not contingent on type of stimuli, and control--no inhibition. While fat intake did not decrease, body-mass index decreased in the food-specific condition and change in this outcome was mediated by changes in vulnerability to depletion. In Study 2, the reliability and longevity of these effects were tested by replicating the intervention with a third measurement time-point. Seventy participants completed baseline, post-intervention and follow-up measures. While inhibitory control and vulnerability to depletion improved in both training conditions post-intervention, eating behaviour and body-mass index did not. Further, improvements in self-regulatory outcomes were not maintained at follow-up. It appears that while the training paradigm employed in the current studies may improve self-regulatory outcomes, it may not necessarily improve health outcomes. It is suggested that this may be due to the task parameters, and that a training paradigm that utilises a higher proportion of stop-signals may be necessary to change behaviour. In addition, improvements in self-regulation do not appear to persist over time. These findings further current conceptualisations of the nature of self-regulation and have implications for the efficacy of online interventions designed to improve eating

  11. Nitrosothiol formation and protection against Fenton chemistry by nitric oxide-induced dinitrosyliron complex formation from anoxia-initiated cellular chelatable iron increase.

    Science.gov (United States)

    Li, Qian; Li, Chuanyu; Mahtani, Harry K; Du, Jian; Patel, Aashka R; Lancaster, Jack R

    2014-07-18

    Dinitrosyliron complexes (DNIC) have been found in a variety of pathological settings associated with (•)NO. However, the iron source of cellular DNIC is unknown. Previous studies on this question using prolonged (•)NO exposure could be misleading due to the movement of intracellular iron among different sources. We here report that brief (•)NO exposure results in only barely detectable DNIC, but levels increase dramatically after 1-2 h of anoxia. This increase is similar quantitatively and temporally with increases in the chelatable iron, and brief (•)NO treatment prevents detection of this anoxia-induced increased chelatable iron by deferoxamine. DNIC formation is so rapid that it is limited by the availability of (•)NO and chelatable iron. We utilize this ability to selectively manipulate cellular chelatable iron levels and provide evidence for two cellular functions of endogenous DNIC formation, protection against anoxia-induced reactive oxygen chemistry from the Fenton reaction and formation by transnitrosation of protein nitrosothiols (RSNO). The levels of RSNO under these high chelatable iron levels are comparable with DNIC levels and suggest that under these conditions, both DNIC and RSNO are the most abundant cellular adducts of (•)NO. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Dinitrosyl iron complexes with thiol-containing ligands as a "working form" of endogenous nitric oxide.

    Science.gov (United States)

    Vanin, Anatoly F

    2016-04-01

    The material presented herein is an overview of the results obtained by our research team during the many years' study of biological activities and occurrence of dinitrosyl iron complexes (DNIC) with thiol-containing ligands in human and animal organisms. With regard to their dose dependence and vast diversity of biological activities, DNIC are similar to the system of endogenous NO, one of the most universal regulators of biological processes. The role of biologically active components in DNIC is played by their iron-dinitrosyl fragments, [Fe(NO)2], endowed with the ability to generate neutral NO molecules and nitrosonium ions (NO(+)). Their release is effected by heme-and thiol-containing proteins, which fulfill the function of biological targets and acceptors of NO and NO(+). Beneficial regulatory effects of DNIC on physiological and metabolic processes are numerous and diverse and include, among other things, lowering of arterial pressure and accelerated healing of skin wounds. In the course of fast decomposition of their Fe(NO)2 fragments (e.g., in the presence of iron chelators), DNIC produce adverse (cytotoxic) effects, which can best be exemplified by their ability to suppress the development of experimental endometriosis in animals. In animal tissues, DNIC with thiol-containing ligands are predominantly represented by the binuclear form, which, contrary to mononuclear DNIC detectable by the 2.03 signal, is EPR-silent. The ample body of evidence on biological activities and occurrence of DNIC gained so far clearly demonstrates that in human and animal organisms DNIC with thiol-containing ligands represent a "working form" of the system of endogenous NO responsible for its accumulation and stabilization in animal tissues as well as its further transfer to its biological targets. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Plasticity of cortical excitatory-inhibitory balance.

    Science.gov (United States)

    Froemke, Robert C

    2015-07-08

    Synapses are highly plastic and are modified by changes in patterns of neural activity or sensory experience. Plasticity of cortical excitatory synapses is thought to be important for learning and memory, leading to alterations in sensory representations and cognitive maps. However, these changes must be coordinated across other synapses within local circuits to preserve neural coding schemes and the organization of excitatory and inhibitory inputs, i.e., excitatory-inhibitory balance. Recent studies indicate that inhibitory synapses are also plastic and are controlled directly by a large number of neuromodulators, particularly during episodes of learning. Many modulators transiently alter excitatory-inhibitory balance by decreasing inhibition, and thus disinhibition has emerged as a major mechanism by which neuromodulation might enable long-term synaptic modifications naturally. This review examines the relationships between neuromodulation and synaptic plasticity, focusing on the induction of long-term changes that collectively enhance cortical excitatory-inhibitory balance for improving perception and behavior.

  14. Inhibitory ability of children with developmental dyscalculia.

    Science.gov (United States)

    Zhang, Huaiying; Wu, Hanrong

    2011-02-01

    Inhibitory ability of children with developmental dyscalculia (DD) was investigated to explore the cognitive mechanism underlying DD. According to the definition of developmental dyscalculia, 19 children with DD-only and 10 children with DD&RD (DD combined with reading disability) were selected step by step, children in two control groups were matched with children in case groups by gender and age, and the match ratio was 1:1. Psychological testing software named DMDX was used to measure inhibitory ability of the subjects. The differences of reaction time in number Stroop tasks and differences of accuracy in incongruent condition of color-word Stroop tasks and object inhibition tasks between DD-only children and their controls reached significant levels (P<0.05), and the differences of reaction time in number Stroop tasks between dyscalculic and normal children did not disappear after controlling the non-executive components. The difference of accuracy in color-word incongruent tasks between children with DD&RD and normal children reached significant levels (P<0.05). Children with DD-only confronted with general inhibitory deficits, while children with DD&RD confronted with word inhibitory deficits only.

  15. Pain perception studies in tension-type headache

    DEFF Research Database (Denmark)

    Bezov, David; Ashina, Sait; Jensen, Rigmor

    2011-01-01

    Tension-type headache (TTH) is a disorder with high prevalence and significant impact on society. Understanding of pathophysiology of TTH is paramount for development of effective treatments and prevention of chronification of TTH. Our aim was to review the findings from pain perception studies...... of pathophysiology of TTH as well as to review the research of pathophysiology of TTH. Pain perception studies such as measurement of muscle tenderness, pain detection thresholds, pain tolerance thresholds, pain response to suprathreshold stimulation, temporal summation and diffuse noxious inhibitory control (DNIC...... to integrate pain perception and imaging to confirm this finding. Pharmacological studies have shown that drugs like tricyclic anti-depressant amitriptyline and nitric oxide synthase inhibitors can reverse central sensitization and the chronicity of headache. Finally, low frequency electrical stimulation has...

  16. Sequential inhibitory control processes assessed through simultaneous EEG-fMRI.

    Science.gov (United States)

    Baumeister, Sarah; Hohmann, Sarah; Wolf, Isabella; Plichta, Michael M; Rechtsteiner, Stefanie; Zangl, Maria; Ruf, Matthias; Holz, Nathalie; Boecker, Regina; Meyer-Lindenberg, Andreas; Holtmann, Martin; Laucht, Manfred; Banaschewski, Tobias; Brandeis, Daniel

    2014-07-01

    Inhibitory response control has been extensively investigated in both electrophysiological (ERP) and hemodynamic (fMRI) studies. However, very few multimodal results address the coupling of these inhibition markers. In fMRI, response inhibition has been most consistently linked to activation of the anterior insula and inferior frontal cortex (IFC), often also the anterior cingulate cortex (ACC). ERP work has established increased N2 and P3 amplitudes during NoGo compared to Go conditions in most studies. Previous simultaneous EEG-fMRI imaging reported association of the N2/P3 complex with activation of areas like the anterior midcingulate cortex (aMCC) and anterior insula. In this study we investigated inhibitory control in 23 healthy young adults (mean age=24.7, n=17 for EEG during fMRI) using a combined Flanker/NoGo task during simultaneous EEG and fMRI recording. Separate fMRI and ERP analysis yielded higher activation in the anterior insula, IFG and ACC as well as increased N2 and P3 amplitudes during NoGo trials in accordance with the literature. Combined analysis modelling sequential N2 and P3 effects through joint parametric modulation revealed correlation of higher N2 amplitude with deactivation in parts of the default mode network (DMN) and the cingulate motor area (CMA) as well as correlation of higher central P3 amplitude with activation of the left anterior insula, IFG and posterior cingulate. The EEG-fMRI results resolve the localizations of these sequential activations. They suggest a general role for allocation of attentional resources and motor inhibition for N2 and link memory recollection and internal reflection to P3 amplitude, in addition to previously described response inhibition as reflected by the anterior insula. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Improving Inhibitory Control Abilities (ImpulsE)-A Promising Approach to Treat Impulsive Eating?

    Science.gov (United States)

    Preuss, Hanna; Pinnow, Marlies; Schnicker, Katja; Legenbauer, Tanja

    2017-11-01

    Although there is preliminary evidence that inhibitory control training improves impulsive eating, less is known about the effects on eating behaviour and weight loss in clinical samples. Sixty-nine treatment-seeking adults with obesity (binge-eating disorder 33.3%; other specific feeding and eating disorders 40.6%) were randomly blockwise allocated to ImpulsE, an intervention to improve inhibitory control and emotion regulation abilities or a guideline-appropriate cognitive behavioural therapy (CBT)-based treatment as usual. Self-reported and performance-based impulsivity, eating disorder pathology and BMI were compared at baseline (T1), post-treatment (T2) and 1- or 3-month follow-up. ImpulsE led to better food-specific inhibition performance (p = .004), but groups did not differ regarding improvements in global Eating Disorder Examination Questionnaire (EDE-Q) score at T2. At 3-month follow-up, binge eaters benefited most from ImpulsE (p = .028) and completers of ImpulsE demonstrated a significantly greater weight reduction (p = .030). The current findings propose ImpulsE as a promising approach to treat obesity, illustrating acceptability and additional benefits for course of weight. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

  18. Executive functions and inhibitory control in multilingual children: Evidence from second-language learners, bilinguals, and trilinguals

    NARCIS (Netherlands)

    Poarch, G.J.; Hell, J.G. van

    2012-01-01

    In two experiments, we examined inhibitory control processes in three groups of bilinguals and trilinguals that differed in nonnative language proficiency and language learning background. German 5- to 8-year-old second-language learners of English, German–English bilinguals, German–English–Language

  19. Dinitrosyl iron complexes and S-nitrosothiols are two possible forms for stabilization and transport of nitric oxide in biological systems.

    Science.gov (United States)

    Vanin, A F

    1998-07-01

    The physicochemical properties, mechanisms of synthesis and decomposition of dinitrosyl iron complexes (DNICs) with thiol-containing ligands and of S-nitrosothiols (RS-NO), and the potential role of these compounds in storage and transport of NO in biological systems are reviewed. Special attention is given to the phenomenon of mutual transformation of DNIC and RS-NO catalyzed by Fe2+. Each Fe2+ binds two neutral NO molecules in the DNICs, catalyzes their mutual oxidation--reduction with formation of nitrous oxide and nitrosonium ions appearing in the DNICs. These ions S-nitrosate thiol-compounds with RS-NO formation. Fe2+ binds two RS-NO molecules and catalyzes their mutual oxidation--reduction followed by decomposition of the resulting molecules. Mutual conversion of DNICs and RS-NO regulated by iron, thiol, and NO levels is suggested to provide NO transport in cells and tissues.

  20. Enhanced inhibitory control by neuropeptide Y Y5 receptor blockade in rats.

    Science.gov (United States)

    Bari, A; Dec, A; Lee, A W; Lee, J; Song, D; Dale, E; Peterson, J; Zorn, S; Huang, X; Campbell, B; Robbins, T W; West, A R

    2015-03-01

    The neuropeptide Y (NPY) system acts in synergy with the classic neurotransmitters to regulate a large variety of functions including autonomic, affective, and cognitive processes. Research on the effects of NPY in the central nervous system has focused on food intake control and affective processes, but growing evidence of NPY involvement in attention-deficit/hyperactivity disorder (ADHD) and other psychiatric conditions motivated the present study. We tested the effects of the novel and highly selective NPY Y5 receptor antagonist Lu AE00654 on impulsivity and the underlying cortico-striatal circuitry in rats to further explore the possible involvement of the NPY system in pathologies characterized by inattention and impulsive behavior. A low dose of Lu AE00654 (0.03 mg/kg) selectively facilitated response inhibition as measured by the stop-signal task, whereas no effects were found at higher doses (0.3 and 3 mg/kg). Systemic administration of Lu AE00654 also enhanced the inhibitory influence of the dorsal frontal cortex on neurons in the caudate-putamen, this fronto-striatal circuitry being implicated in the executive control of behavior. Finally, by locally injecting a Y5 agonist, we observed reciprocal activation between dorsal frontal cortex and caudate-putamen neurons. Importantly, the effects of the Y5 agonist were attenuated by pretreatment with Lu AE00654, confirming the presence of Y5 binding sites modulating functional interactions within frontal-subcortical circuits. These results suggest that the NPY system modulates inhibitory neurotransmission in brain areas important for impulse control, and may be relevant for the treatment of pathologies such as ADHD and drug abuse.

  1. Pain perception studies in tension-type headache.

    Science.gov (United States)

    Bezov, David; Ashina, Sait; Jensen, Rigmor; Bendtsen, Lars

    2011-02-01

    Tension-type headache (TTH) is a disorder with high prevalence and significant impact on society. Understanding of pathophysiology of TTH is paramount for development of effective treatments and prevention of chronification of TTH. Our aim was to review the findings from pain perception studies of pathophysiology of TTH as well as to review the research of pathophysiology of TTH. Pain perception studies such as measurement of muscle tenderness, pain detection thresholds, pain tolerance thresholds, pain response to suprathreshold stimulation, temporal summation and diffuse noxious inhibitory control (DNIC) have played a central role in elucidating the pathophysiology of TTH. It has been demonstrated that continuous nociceptive input from peripheral myofascial structures may induce central sensitization and thereby chronification of the headache. Measurements of pain tolerance thresholds and suprathreshold stimulation have shown presence of generalized hyperalgesia in chronic tension-type headache (CTTH) patients, while DNIC function has been shown to be reduced in CTTH. One imaging study showed loss of gray matter structures involved in pain processing in CTTH patients. Future studies should aim to integrate pain perception and imaging to confirm this finding. Pharmacological studies have shown that drugs like tricyclic anti-depressant amitriptyline and nitric oxide synthase inhibitors can reverse central sensitization and the chronicity of headache. Finally, low frequency electrical stimulation has been shown to rapidly reverse central sensitization and may be a new modality in treatment of CTTH and other chronic pain disorders. © 2010 American Headache Society.

  2. Influence of age, circadian and homeostatic processes on inhibitory motor control: a Go/Nogo task study.

    Directory of Open Access Journals (Sweden)

    Patricia Sagaspe

    Full Text Available INTRODUCTION: The contribution of circadian system and sleep pressure influences on executive performance as a function of age has never been studied. The aim of our study was to determine the age-related evolution of inhibitory motor control (i.e., ability to suppress a prepotent motor response and sustained attention under controlled high or low sleep pressure conditions. METHODS: 14 healthy young males (mean age = 23 ± 2.7; 20-29 years and 11 healthy older males (mean age = 68 ± 1.4; 66-70 years were recruited. The volunteers were placed for 40 hours in "constant routine". In the "Sleep Deprivation SD" condition, the volunteer was kept awake for 40 hours to obtain a high sleep pressure condition interacting with the circadian process. In the "NAP" condition, the volunteer adopted a short wake/sleep cycle (150/75 min resulting in a low sleep pressure condition to counteract the homeostatic pressure and investigate the circadian process. Performances were evaluated by a simple reaction time task and a Go/Nogo task repeated every 3H45. RESULTS: In the SD condition, inhibitory motor control (i.e., ability to inhibit an inappropriate response was impaired by extended wakefulness equally in both age groups (P<.01. Sustained attention (i.e. ability to respond accurately to appropriate stimuli on the executive task decreased under sleep deprivation in both groups, and even more in young participants (P<.05. In the NAP condition, age did not influence the time course of inhibitory motor control or sustained attention. In the SD and NAP conditions, older participants had a less fluctuating reaction time performance across time of day than young participants (P<.001. CONCLUSION: Aging could be a protective factor against the effects of extended wakefulness especially on sustained attention failures due to an attenuation of sleep pressure with duration of time awake.

  3. ADHD and retrieval-induced forgetting: evidence for a deficit in the inhibitory control of memory.

    Science.gov (United States)

    Storm, Benjamin C; White, Holly A

    2010-04-01

    Research on retrieval-induced forgetting has shown that the selective retrieval of some information can cause the forgetting of other information. Such forgetting is believed to result from inhibitory processes that function to resolve interference during retrieval. The current study examined whether individuals with ADHD demonstrate normal levels of retrieval-induced forgetting. A total of 40 adults with ADHD and 40 adults without ADHD participated in a standard retrieval-induced forgetting experiment. Critically, half of the items were tested using category cues and the other half of the items were tested using category-plus-one-letter-stem cues. Whereas both ADHD and non-ADHD participants demonstrated retrieval-induced forgetting on the final category-cued recall test, only non-ADHD participants demonstrated retrieval-induced forgetting on the final category-plus-stem-cued recall test. These results suggest that individuals with ADHD do have a deficit in the inhibitory control of memory, but that this deficit may only be apparent when output interference is adequately controlled on the final test.

  4. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

    Directory of Open Access Journals (Sweden)

    Shohei Sakuda

    2014-03-01

    Full Text Available Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control.

  5. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

    Science.gov (United States)

    Sakuda, Shohei; Prabowo, Diyan Febri; Takagi, Keiko; Shiomi, Kazuro; Mori, Mihoko; Ōmura, Satoshi; Nagasawa, Hiromichi

    2014-01-01

    Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A) inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III) and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control. PMID:24674936

  6. Not doing bad things is not equivalent to doing the right thing: distinguishing between inhibitory and initiatory self-control

    NARCIS (Netherlands)

    De Ridder, D.T.D.; de Boer, Benjamin; Lugtig, P.J.; Bakker, A.B.; van Hooft, E.A.J.

    The present study investigated whether a conceptual distinction between two components of self-control (inhibitory and initiatory self-control) is empirically valid. To that purpose, a series of confirmative factor analyses were employed in two samples (total N = 577), providing support for a

  7. Inhibitory Control of Spanish-Speaking Language-Minority Preschool Children: Measurement and Association With Language, Literacy, and Math Skills.

    Science.gov (United States)

    Lonigan, Christopher J; Allan, Darcey M; Goodrich, J Marc; Farrington, Amber L; Phillips, Beth M

    Children's self-regulation, including components of executive function such as inhibitory control, is related concurrently and longitudinally with elementary school children's reading and math abilities. Although several recent studies have examined links between preschool children's self-regulation or executive function and their academic skill development, few included large numbers of Spanish-speaking language-minority children. Among the fastest growing segments of the U.S. school-age population, many of these children are at significant risk of academic difficulties. We examined the relations between inhibitory control and academic skills in a sample containing a large number of Spanish-speaking preschoolers. Overall, the children demonstrated substantial academic risk based on preschool-entry vocabulary scores in the below-average range. Children completed assessments of language, literacy, and math skills in English and Spanish, when appropriate, at the start and end of their preschool year, along with a measure of inhibitory control, the Head-Toes-Knees-Shoulders task, which was administered at the start of the preschool year in the child's dominant conversational language. Scores on this last measure were lower for children for whom it was administered in Spanish. For both English and Spanish outcomes, those scores were significantly and uniquely associated with higher scores on measures of phonological awareness and math skills but not vocabulary or print knowledge skills.

  8. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents

    DEFF Research Database (Denmark)

    Domazet, Sidsel L; Tarp, Jakob; Huang, Tao

    2016-01-01

    OBJECTIVES: To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. METHODS: The design was cross-sectional. A convenient sample of 869 sixth and seventh gra...

  9. Executive functions and inhibitory control in multilingual children: evidence from second-language learners, bilinguals, and trilinguals.

    Science.gov (United States)

    Poarch, Gregory J; van Hell, Janet G

    2012-12-01

    In two experiments, we examined inhibitory control processes in three groups of bilinguals and trilinguals that differed in nonnative language proficiency and language learning background. German 5- to 8-year-old second-language learners of English, German-English bilinguals, German-English-Language X trilinguals, and 6- to 8-year-old German monolinguals performed the Simon task and the Attentional Networks Task (ANT). Language proficiencies and socioeconomic status were controlled. We found that the Simon effect advantage, reported in earlier research for bilingual children and adults over monolinguals, differed across groups, with bilinguals and trilinguals showing enhanced conflict resolution over monolinguals and marginally so over second-language learners. In the ANT, bilinguals and trilinguals displayed enhanced conflict resolution over second-language learners. This extends earlier research to child second-language learners and trilinguals, who were in the process of becoming proficient in an additional language, while corroborating earlier findings demonstrating enhanced executive control in bilinguals assumed to be caused by continuous inhibitory control processes necessary in competition resolution between two (or possibly more) languages. The results are interpreted against the backdrop of the developing language systems of the children, both for early second-language learners and for early bilinguals and trilinguals. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. The role of emotional inhibitory control in specific internet addiction - an fMRI study.

    Science.gov (United States)

    Dieter, Julia; Hoffmann, Sabine; Mier, Daniela; Reinhard, Iris; Beutel, Martin; Vollstädt-Klein, Sabine; Kiefer, Falk; Mann, Karl; Leménager, Tagrid

    2017-05-01

    Addicts to specific internet applications involving communication features showed increased social anxiety, emotional competence deficits and impaired prefrontal-related inhibitory control. The dorsal Anterior Cingulate Cortex (dACC) likely plays an important role in cognitive control and negative affect (such as social exclusion, pain or anxiety). To assess (social) anxiety-related inhibitory control in specific internet addiction (addicted use of games and social networks) and its relation to altered dACC activation. N=44 controls and n=51 specific internet addicts completed an anxious words-based Affective Go/No-Go task (AGN). A subsample of n=23 healthy controls and n=25 specific internet addicts underwent functional Magnetic Resonance Imaging (fMRI) while completing an Emotional Stroop Task (EST) with socially anxious, positive, negative and neutral words. Subgroups of internet gaming and social network addicts were exploratively assessed. Psychometric measures of social anxiety, emotional competence and impulsivity were additionally explored. Specific internet addicts showed higher impulsivity, social anxiety and reduced emotional competence. Between-group differences in AGN and EST behavioral measures were not detected. No group differences were found in the dACC, but explorative analyses revealed decreased left middle and superior temporal gyrus activation during interference of socially anxious words in internet gaming and relative to social network addicts. Given the function of the left middle temporal gyrus in the retrieval of words or expressions during communication, our findings give a first hint that social words might be less retrievable in the semantic storage of internet gaming addicts, possibly indicating deficiencies in handling speech in social situations. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Executive Functions and Inhibitory Control in Multilingual Children: Evidence from Second-Language Learners, Bilinguals, and Trilinguals

    Science.gov (United States)

    Poarch, Gregory J.; van Hell, Janet G.

    2012-01-01

    In two experiments, we examined inhibitory control processes in three groups of bilinguals and trilinguals that differed in nonnative language proficiency and language learning background. German 5- to 8-year-old second-language learners of English, German-English bilinguals, German-English-Language X trilinguals, and 6- to 8-year-old German…

  12. Brain and behavioral inhibitory control of kindergartners facing negative emotions.

    Science.gov (United States)

    Farbiash, Tali; Berger, Andrea

    2016-09-01

    Inhibitory control (IC) - one of the most critical functions underlying a child's ability to self-regulate - develops significantly throughout the kindergarten years. Experiencing negative emotions imposes challenges on executive functioning and may specifically affect IC. In this study, we examined kindergartners' IC and its related brain activity during a negative emotional situation: 58 children (aged 5.5-6.5 years) performed an emotion-induction Go/NoGo task. During this task, we recorded children's performance and brain activity, focusing on the fronto-central N2 component in the event-related potential (ERP) and the power of its underlying theta frequency. Compared to Go trials, inhibition of NoGo trials was associated with larger N2 amplitudes and theta power. The negative emotional experience resulted in better IC performance and, at the brain level, in larger theta power. Source localization of this effect showed that the brain activity related to IC during the negative emotional experience was principally generated in the posterior frontal regions. Furthermore, the band power measure was found to be a more sensitive index for children's inhibitory processes than N2 amplitudes. This is the first study to focus on kindergartners' IC while manipulating their emotional experience to induce negative emotions. Our findings suggest that a kindergartner's experience of negative emotion can result in improved IC and increases in associated aspects of brain activity. Our results also suggest the utility of time-frequency analyses in the study of brain processes associated with response inhibition in young children. © 2015 John Wiley & Sons Ltd.

  13. Neurobiological correlates of avatar identification processing and emotional inhibitory control in internet gaming disorder

    OpenAIRE

    Dieter, Julia

    2017-01-01

    Internet gaming disorder (IGD) is the most prevalent subcategory of internet addiction. It has been associated with self-concept deficits and related characteristics such as emotional as well as social competence deficits, increased social anxiety and a stronger identification with the own avatar (i.e. a graphical agent that often seems to be constructed according to gamers’ ideal). In addition, IGD seems to be linked with inhibitory control deficits, definable as impairments in the inhibitio...

  14. General and Food-Specific Inhibitory Control As Moderators of the Effects of the Impulsive Systems on Food Choices

    Directory of Open Access Journals (Sweden)

    Xuemeng Zhang

    2017-05-01

    Full Text Available The present study aimed to extend the application of the reflective-impulsive model to restrained eating and explore the effect of automatic attention (impulsive system on food choices. Furthermore, we examined the moderating effects of general inhibitory control (G-IC and food-specific inhibitory control (F-IC on successful and unsuccessful restrained eaters (US-REs. Automatic attention was measured using “the EyeLink 1000,” which tracked eye movements during the process of making food choices, and G-IC and F-IC were measured using the Stop-Signal Task. The results showed that food choices were related to automatic attention and that G-IC and F-IC moderated the predictive relationship between automatic attention and food choices. Furthermore, among successful restrained eaters (S-REs, automatic attention to high caloric foods did not predict food choices, regardless of whether G-IC or F-IC was high or low. Whereas food choice was positively correlated with automatic attention among US-REs with poor F-IC, this pattern was not observed in those with poor G-IC. In conclusion, the S-REs had more effective self-management skills and their food choices were affected less by automatic attention and inhibitory control. Unsuccessful restrained eating was associated with poor F-IC (not G-IC and greater automatic attention to high caloric foods. Thus, clinical interventions should focus on enhancing F-IC, not G-IC, and on reducing automatic attention to high caloric foods.

  15. Differential influence of safe versus threatening facial expressions on decision-making during an inhibitory control task in adolescence and adulthood.

    Science.gov (United States)

    Cohen-Gilbert, J E; Killgore, W D S; White, C N; Schwab, Z J; Crowley, D J; Covell, M J; Sneider, J T; Silveri, M M

    2014-03-01

    Social cognition matures dramatically during adolescence and into early adulthood, supported by continued improvements in inhibitory control. During this time, developmental changes in interpreting and responding to social signals such as facial expressions also occur. In the present study, subjects performed a Go No-Go task that required them to respond or inhibit responding based on threat or safety cues present in facial expressions. Subjects (N = 112) were divided into three age groups: adolescent (12-15 years), emerging adult (18-25 years) and adult (26-44 years). Analyses revealed a significant improvement in accuracy on No-Go trials, but not Go trials, during both safe and threat face conditions, with changes evident through early adulthood. In order to better identify the decision-making processes responsible for these changes in inhibitory control, a drift diffusion model (DDM) was fit to the accuracy and reaction time data, generating measures of caution, response bias, nondecision time (encoding + motor response), and drift rate (face processing efficiency). Caution and nondecision time both increased significantly with age while bias towards the Go response decreased. Drift rate analyses revealed significant age-related improvements in the ability to map threat faces to a No-Go response while drift rates on all other trial types were equivalent across age groups. These results suggest that both stimulus-independent and stimulus-dependent processes contribute to improvements in inhibitory control in adolescence with processing of negative social cues being specifically impaired by self-regulatory demands. Findings from this novel investigation of emotional responsiveness integrated with inhibitory control may provide useful insights about healthy development that can be applied to better understand adolescent risk-taking behavior and the elevated incidence of related forms of psychopathology during this period of life. © 2014 John Wiley & Sons Ltd.

  16. Degree of synchronization modulated by inhibitory neurons in clustered excitatory-inhibitory recurrent networks

    Science.gov (United States)

    Li, Huiyan; Sun, Xiaojuan; Xiao, Jinghua

    2018-01-01

    An excitatory-inhibitory recurrent neuronal network is established to numerically study the effect of inhibitory neurons on the synchronization degree of neuronal systems. The obtained results show that, with the number of inhibitory neurons and the coupling strength from an inhibitory neuron to an excitatory neuron increasing, inhibitory neurons can not only reduce the synchronization degree when the synchronization degree of the excitatory population is initially higher, but also enhance it when it is initially lower. Meanwhile, inhibitory neurons could also help the neuronal networks to maintain moderate synchronized states. In this paper, we call this effect as modulation effect of inhibitory neurons. With the obtained results, it is further revealed that the ratio of excitatory neurons to inhibitory neurons being nearly 4 : 1 is an economic and affordable choice for inhibitory neurons to realize this modulation effect.

  17. An Event-Related Potential and Behavioral Study of Impaired Inhibitory Control in Children with Autism Spectrum Disorder

    Science.gov (United States)

    Tsai, Chia-Liang; Pan, Chien-Yu; Wang, Chun-Hao; Tseng, Yu-Ting; Hsieh, Kai-Wen

    2011-01-01

    Autism spectrum disorders (ASD) are characterized by a deficit of dorsal visual stream processing as well as the impairment of inhibitory control capability. However, the cognitive processing mechanisms of executive dysfunction have not been addressed. In the present study, the endogenous Posner paradigm task was administered to 15 children with…

  18. Inhibitory Control as a Core Process of Creative Problem Solving and Idea Generation from Childhood to Adulthood

    Science.gov (United States)

    Cassotti, Mathieu; Agogué, Marine; Camarda, Anaëlle; Houdé, Olivier; Borst, Grégoire

    2016-01-01

    Developmental cognitive neuroscience studies tend to show that the prefrontal brain regions (known to be involved in inhibitory control) are activated during the generation of creative ideas. In the present article, we discuss how a dual-process model of creativity--much like the ones proposed to account for decision making and reasoning--could…

  19. Inhibitory noise

    Directory of Open Access Journals (Sweden)

    Alain Destexhe

    2010-03-01

    Full Text Available Cortical neurons in vivo may operate in high-conductance states, in which the major part of the neuron's input conductance is due to synaptic activity, sometimes several-fold larger than the resting conductance. We examine here the contribution of inhibition in such high-conductance states. At the level of the absolute conductance values, several studies have shown that cortical neurons in vivo are characterized by strong inhibitory conductances. However, conductances are balanced and spiking activity is mostly determined by fluctuations, but not much is known about excitatory and inhibitory contributions to these fluctuations. Models and dynamic-clamp experiments show that, during high-conductance states, spikes are mainly determined by fluctuations of inhibition, or by inhibitory noise. This stands in contrast to low-conductance states, in which excitatory conductances determine spiking activity. To determine these contributions from experimental data, maximum likelihood methods can be designed and applied to intracellular recordings in vivo. Such methods indicate that action potentials are indeed mostly correlated with inhibitory fluctuations in awake animals. These results argue for a determinant role for inhibitory fluctuations in evoking spikes, and do not support feed-forward modes of processing, for which opposite patterns are predicted.

  20. Thalamic inputs to dorsomedial striatum are involved in inhibitory control: evidence from the five-choice serial reaction time task in rats.

    Science.gov (United States)

    Saund, Jasjot; Dautan, Daniel; Rostron, Claire; Urcelay, Gonzalo P; Gerdjikov, Todor V

    2017-08-01

    Corticostriatal circuits are widely implicated in the top-down control of attention including inhibitory control and behavioural flexibility. However, recent neurophysiological evidence also suggests a role for thalamic inputs to striatum in behaviours related to salient, reward-paired cues. Here, we used designer receptors exclusively activated by designer drugs (DREADDs) to investigate the role of parafascicular (Pf) thalamic inputs to the dorsomedial striatum (DMS) using the five-choice serial reaction time task (5CSRTT) in rats. The 5CSRTT requires sustained attention in order to detect spatially and temporally distributed visual cues and provides measures of inhibitory control related to impulsivity (premature responses) and compulsivity (perseverative responses). Rats underwent bilateral Pf injections of the DREADD vector, AAV2-CaMKIIa-HA-hM4D(Gi)-IRES-mCitrine. The DREADD agonist, clozapine N-oxide (CNO; 1 μl bilateral; 3 μM) or vehicle, was injected into DMS 1 h before behavioural testing. Task parameters were manipulated to increase attention load or reduce stimulus predictability respectively. We found that inhibition of the Pf-DMS projection significantly increased perseverative responses when stimulus predictability was reduced but had no effect on premature responses or response accuracy, even under increased attentional load. Control experiments showed no effects on locomotor activity in an open field. These results complement previous lesion work in which the DMS and orbitofrontal cortex were similarly implicated in perseverative responses and suggest a specific role for thalamostriatal inputs in inhibitory control.

  1. [The dinitrosyl-iron complexes with cysteine block the development of experimental endometriosis in rats].

    Science.gov (United States)

    Burgova, E N; Tkachev, N A; Vanin, A F

    2012-01-01

    It has been shown that the administration of 0,5 ml of 5 mM aqueous solution of dinitrosyl-iron complexes (DNIC) with cysteine alleviated the development of experimental endometriosis in rats induced by surgical way: the size of endometriomes decreased 1.85 times when the DNIC was added every day during 10 days. The effect was suggested to be due to cytotoxic action of NO molecules and nitrosonium ions (NO+) released from rapidly decomposed DNIC in animal organism on endometriome tissues.

  2. Rejection Positivity Predicts Trial-to-Trial Reaction Times in an Auditory Selective Attention Task: A Computational Analysis of Inhibitory Control

    Directory of Open Access Journals (Sweden)

    Sufen eChen

    2014-08-01

    Full Text Available A series of computer simulations using variants of a formal model of attention (Melara & Algom, 2003 probed the role of rejection positivity (RP, a slow-wave electroencephalographic (EEG component, in the inhibitory control of distraction. Behavioral and EEG data were recorded as participants performed auditory selective attention tasks. Simulations that modulated processes of distractor inhibition accounted well for reaction-time (RT performance, whereas those that modulated target excitation did not. A model that incorporated RP from actual EEG recordings in estimating distractor inhibition was superior in predicting changes in RT as a function of distractor salience across conditions. A model that additionally incorporated momentary fluctuations in EEG as the source of trial-to-trial variation in performance precisely predicted individual RTs within each condition. The results lend support to the linking proposition that RP controls the speed of responding to targets through the inhibitory control of distractors.

  3. Training on Working Memory and Inhibitory Control in Young Adults

    Directory of Open Access Journals (Sweden)

    Maria Jesus Maraver

    2016-11-01

    Full Text Available Different types of interventions have focused on trying to improve Executive Functions (EF due to their essential role in human cognition and behavior regulation. Although EF are thought to be diverse, most training studies have targeted cognitive processes related to working memory (WM, and fewer have focused on training other control mechanisms, such as inhibitory control (IC. In the present study, we aimed to investigate the differential impact of training WM and IC as compared with control conditions performing non-executive control activities. Young adults were divided into two training (WM/IC and two (active/passive control conditions. Over six sessions, the training groups engaged in three different computer-based adaptive activities (WM or IC, whereas the active control group completed a program with low control-demanding activities that mainly involved processing speed. In addition, motivation and engagement were monitored through the training. The WM-training activities required maintenance, updating and memory search processes, while those from the IC group engaged response inhibition, and interference control. All participants were pre- and post-tested in criterion tasks (n-back and Stroop, near transfer measures of WM (Operation Span and IC (Stop-Signal. Non-trained far transfer outcome measures included an abstract reasoning test (Raven’s Advanced Progressive Matrices and a well-validated experimental task (AX-CPT that provides indices of cognitive flexibility considering proactive/reactive control. Training results revealed that strongly motivated participants reached higher levels of training improvements. Regarding transfer effects, results showed specific patterns of near transfer effects depending on the type of training. Interestingly, it was only the IC training group that showed far transfer to reasoning. Finally, all trained participants showed a shift towards a more proactive mode of cognitive control, highlighting a

  4. Differential Diagnosis of Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder by Means of Inhibitory Control and "Theory of Mind"

    Science.gov (United States)

    Buhler, Eva; Bachmann, Christian; Goyert, Hannah; Heinzel-Gutenbrunner, Monika; Kamp-Becker, Inge

    2011-01-01

    Autism spectrum disorders (ASD) and attention deficit hyperactivity disorders (ADHD) are both associated with deficits in executive control and with problems in social contexts. This study analyses the variables inhibitory control and theory of mind (ToM), including a developmental aspect in the case of the latter, to differentiate between the…

  5. Music training and inhibitory control: a multidimensional model.

    Science.gov (United States)

    Moreno, Sylvain; Farzan, Faranak

    2015-03-01

    Training programs aimed to improve cognitive skills have either yielded mixed results or remain to be validated. The limited benefits of such regimens are largely attributable to weak understanding of (1) how (and which) interventions provide the most cognitive improvements; and (2) how brain networks and neural mechanisms that underlie specific cognitive abilities can be modified selectively. Studies indicate that music training leads to robust and long-lasting benefits to behavior. Importantly, behavioral advantages conferred by music extend beyond perceptual abilities to even nonauditory functions, such as inhibitory control (IC) and its neural correlates. Alternative forms of arts engagement or brain training do not appear to yield such enhancements, which suggests that music uniquely taps into brain networks subserving a variety of auditory as well as domain-general mechanisms such as IC. To account for such widespread benefits of music training, we propose a framework of transfer effects characterized by three dimensions: level of processing, nature of the transfer, and involvement of executive functions. We suggest that transfer of skills is mediated through modulation of general cognitive processes, in particular IC. We believe that this model offers a viable framework to test the extent and limitations of music-related changes. © 2014 New York Academy of Sciences.

  6. Evidence for superior neurobiological and behavioral inhibitory control abilities in non-offending as compared to offending pedophiles.

    Science.gov (United States)

    Kärgel, Christian; Massau, Claudia; Weiß, Simone; Walter, Martin; Borchardt, Viola; Krueger, Tillmann H C; Tenbergen, Gilian; Kneer, Jonas; Wittfoth, Matthias; Pohl, Alexander; Gerwinn, Hannah; Ponseti, Jorge; Amelung, Till; Beier, Klaus M; Mohnke, Sebastian; Walter, Henrik; Schiffer, Boris

    2017-02-01

    Neurobehavioral models of pedophilia and child sexual offending suggest a pattern of temporal and in particular prefrontal disturbances leading to inappropriate behavioral control and subsequently an increased propensity to sexually offend against children. However, clear empirical evidence for such mechanisms is still missing. Using a go/nogo paradigm in combination with functional magnetic resonance imaging (fMRI) we compared behavioral performance and neural response patterns among three groups of men matched for age and IQ: pedophiles with (N = 40) and without (N = 37) a history of hands-on sexual offences against children as well as healthy non-offending controls (N = 40). As compared to offending pedophiles, non-offending pedophiles exhibited superior inhibitory control as reflected by significantly lower rate of commission errors. Group-by-condition interaction analysis also revealed inhibition-related activation in the left posterior cingulate and the left superior frontal cortex that distinguished between offending and non-offending pedophiles, while no significant differences were found between pedophiles and healthy controls. Both areas showing distinct activation pattern among pedophiles play a critical role in linking neural networks that relate to effective cognitive functioning. Data therefore suggest that heightened inhibition-related recruitment of these areas as well as decreased amount of commission errors is related to better inhibitory control in pedophiles who successfully avoid committing hands-on sexual offences against children. Hum Brain Mapp 38:1092-1104, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Systematic review of ERP and fMRI studies investigating inhibitory control and error processing in people with substance dependence and behavioural addictions

    NARCIS (Netherlands)

    Luijten, Maartje; Machielsen, Marise W. J.; Veltman, Dick J.; Hester, Robert; de Haan, Lieuwe; Franken, Ingmar H. A.

    2014-01-01

    Several current theories emphasize the role of cognitive control in addiction. The present review evaluates neural deficits in the domains of inhibitory control and error processing in individuals with substance dependence and in those showing excessive addiction-like behaviours. The combined

  8. Systematic review of ERP and fMRI studies investigating inhibitory control and error processing in people with substance dependence and behavioural addictions

    NARCIS (Netherlands)

    Luijten, M.; Machielsen, M.W.J.; Veltman, D.J.; Hester, R.; de Haan, L.; Franken, I.H.A.

    2014-01-01

    Background: Several current theories emphasize the role of cognitive control in addiction. The present review evaluates neural deficits in the domains of inhibitory control and error processing in individuals with substance dependence and in those showing excessive addiction-like behaviours. The

  9. Alcohol use disorder with and without stimulant use: brain morphometry and its associations with cigarette smoking, cognition, and inhibitory control.

    Directory of Open Access Journals (Sweden)

    David L Pennington

    Full Text Available Little is known about the effects of polysubstance use and cigarette smoking on brain morphometry. This study examined neocortical brain morphometric differences between abstinent polysubstance dependent and alcohol-only dependent treatment seekers (ALC as well as light drinking controls (CON, the associations of cigarette smoking in these polysubstance users (PSU, and morphometric relationships to cognition and inhibitory control.All participants completed extensive neuropsychological assessments and 4 Tesla brain magnetic resonance imaging. PSU and ALC were abstinent for one month at the time of study. Parcellated morphological data (volume, surface area, thickness were obtained with FreeSurfer methodology for the following bilateral components: dorso-prefrontal cortex (DPFC, anterior cingulate cortex (ACC, orbitofrontal cortex (OFC, and insula. Regional group differences were examined and structural data correlated with domains of cognition and inhibitory control.PSU had significantly smaller left OFC volume and surface area and trends to smaller right DPFC volume and surface area compared to CON; PSU did not differ significantly from ALC on these measures. PSU, however, had significantly thinner right ACC than ALC. Smoking PSU had significantly larger right OFC surface area than non-smoking PSU. No significant relationships between morphometry and quantity/frequency of substance use, alcohol use, or age of onset of heavy drinking were observed. PSU exhibited distinct relationships between brain structure and processing speed, cognitive efficiency, working memory and inhibitory control that were not observed in ALC or CON.Polysubstance users have unique morphometric abnormalities and structure-function relationships when compared to individuals dependent only on alcohol and light drinking controls. Chronic cigarette smoking is associated with structural brain irregularities in polysubstance users. Further elucidation of these distinctive

  10. Inhibitory Control as a Core Process of Creative Problem Solving and Idea Generation from Childhood to Adulthood.

    Science.gov (United States)

    Cassotti, Mathieu; Agogué, Marine; Camarda, Anaëlle; Houdé, Olivier; Borst, Grégoire

    2016-01-01

    Developmental cognitive neuroscience studies tend to show that the prefrontal brain regions (known to be involved in inhibitory control) are activated during the generation of creative ideas. In the present article, we discuss how a dual-process model of creativity-much like the ones proposed to account for decision making and reasoning-could broaden our understanding of the processes involved in creative ideas generation. When generating creative ideas, children, adolescents, and adults tend to follow "the path of least resistance" and propose solutions that are built on the most common and accessible knowledge within a specific domain, leading to fixation effect. In line with recent theory of typical cognitive development, we argue that the ability to resist the spontaneous activation of design heuristics, to privilege other types of reasoning, might be critical to generate creative ideas at all ages. In the present review, we demonstrate that inhibitory control at all ages can actually support creativity. Indeed, the ability to think of something truly new and original requires first inhibiting spontaneous solutions that come to mind quickly and unconsciously and then exploring new ideas using a generative type of reasoning. © 2016 Wiley Periodicals, Inc.

  11. Cardiorespiratory fitness is associated with selective attention and inhibitory control in healthy male high-school students

    OpenAIRE

    Wengaard, Eivind Johannessen; Kristoffersen, Morten; Harris, Anette; Gundersen, Hilde

    2017-01-01

    Background: Previous studies have shown associations of physical fitness and cognition in children and in younger and older adults. However, knowledge about associations in high-school adolescents and young adults is sparse. Thus, the aim of this study was to evaluate the association of physical fitness, measured as maximal oxygen uptake (V⋅O2max), muscle mass, weekly training, and cognitive function in the executive domains of selective attention and inhibitory control, in healthy male ...

  12. Heterogeneity in Maltreated and Non-maltreated Preschool Children’s Inhibitory Control: The Interplay Between Parenting Quality and Child Temperament

    OpenAIRE

    Cipriano-Essel, Elizabeth; Skowron, Elizabeth A.; Stifter, Cynthia A.; Teti, Douglas M.

    2013-01-01

    This study examined the contribution of child temperament, parenting, and their interaction on inhibitory control development in a sample of maltreated and non-maltreated preschool children. One hundred and eighteen mother–child dyads were drawn from predominantly low-income, rural communities. Dyads participated in a laboratory session in which maternal warm autonomy support, warm guidance, and strict/hostile control were observationally coded during a joint teaching task. Independent assess...

  13. The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language.

    Science.gov (United States)

    Lu, Yao; Wu, Junjie; Dunlap, Susan; Chen, Baoguo

    2017-01-01

    Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2) learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese-English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning) and half were ambiguous (had two semantically unrelated meanings learned in sequence). Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

  14. The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language

    Directory of Open Access Journals (Sweden)

    Baoguo Chen

    2017-04-01

    Full Text Available Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2 learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese–English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning and half were ambiguous (had two semantically unrelated meanings learned in sequence. Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

  15. Inhibitory and Working Memory Demands of the Day-Night Task in Children

    Science.gov (United States)

    Simpson, Andrew; Riggs, Kevin J.

    2005-01-01

    Gerstadt, Hong, and Diamond (1994) investigated the development of inhibitory control in children aged 3 1/2 - 7 years using the day-night task. In two studies we build on Gerstadt et al.'s findings with a measure of inhibitory control that can be used throughout childhood. In Study 1 (twenty-four 3 1/2-year-olds and sixteen 5-year-olds) we…

  16. Selective deficiencies in descending inhibitory modulation in neuropathic rats: implications for enhancing noradrenergic tone.

    Science.gov (United States)

    Patel, Ryan; Qu, Chaoling; Xie, Jennifer Y; Porreca, Frank; Dickenson, Anthony H

    2018-05-31

    Pontine noradrenergic neurones form part of a descending inhibitory system that influences spinal nociceptive processing. Weak or absent descending inhibition is a common feature of chronic pain patients. We examined the extent to which the descending noradrenergic system is tonically active, how control of spinal neuronal excitability is integrated into thalamic relays within sensory-discriminative projection pathways, and how this inhibitory control is altered after nerve injury. In vivo electrophysiology was performed in anaesthetised spinal nerve ligated (SNL) and sham-operated rats to record from wide dynamic range neurones in the ventral posterolateral thalamus (VPL). In sham rats, spinal block of α2-adrenoceptors with atipamezole resulted in enhanced stimulus-evoked and spontaneous firing in the VPL, and produced conditioned place avoidance. However, in SNL rats these conditioned avoidance behaviours were absent. Furthermore, inhibitory control of evoked neuronal responses was lost but spinal atipamezole markedly increased spontaneous firing. Augmenting spinal noradrenergic tone in neuropathic rats with reboxetine, a selective noradrenergic reuptake inhibitor, modestly reinstated inhibitory control of evoked responses in the VPL but had no effect on spontaneous firing. In contrast, clonidine, an α2 agonist, inhibited both evoked and spontaneous firing, and exhibited increased potency in SNL rats compared to sham controls. These data suggest descending noradrenergic inhibitory pathways are tonically active in sham rats. Moreover, in neuropathic states descending inhibitory control is diminished, but not completely absent, and distinguishes between spontaneous and evoked neuronal activity. These observations may have implications for how analgesics targeting the noradrenergic system provide relief.

  17. Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders

    Science.gov (United States)

    2016-12-01

    1 AWARD NUMBER: W81XWH-14-1-0433 TITLE: Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders PRINCIPAL INVESTIGATOR: Anis...SUBTITLE 5a. CONTRACT NUMBER Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders 5b. GRANT NUMBER W81XWH-14-1-0433 5c. PROGRAM...chloride co-transporters that control EGABA could be used as a corrective strategy for the synaptic and circuit disruptions demonstrated in the

  18. Coupling of online control and inhibitory systems in children with atypical motor development: A growth curve modelling study.

    Science.gov (United States)

    Ruddock, Scott; Caeyenberghs, Karen; Piek, Jan; Sugden, David; Hyde, Christian; Morris, Sue; Rigoli, Daniela; Steenbergen, Bert; Wilson, Peter

    2016-11-01

    Previous research indicates that children with Developmental Coordination Disorder (DCD) show deficits performing online corrections, an issue exacerbated by adding inhibitory constraints; however, cross-sectional data suggests that these deficits may reduce with age. Using a longitudinal design, the aim of the study presented here was to model the coupling that occurs between inhibitory systems and (predictive) online control in typically developing children (TDC) and in those with Developmental Coordination Disorder (DCD) over an extended period of time, using a framework of interactive specialization. We predicted that TDC would show a non-linear growth pattern, consistent with re-organisation in the coupling during the middle childhood period, while DCD would display a developmental lag. A group of 196 children (111 girls and 85 boys) aged between 6 and 12years participated in the study. Children were classified as DCD according to research criteria. Using a cohort sequential design, both TDC and DCD groups were divided into age cohorts. Predictive (online) control was defined operationally by performance on a Double-Jump Reaching Task (DJRT), which was assessed at 6-month intervals over two years (5 time points in total). Inhibitory control was examined using an anti-jump condition of the DJRT paradigm whereby children were instructed to touch a target location in the hemispace opposite a cued location. For the TDC group, model comparison using growth curve analysis revealed that a quadratic trend was the most appropriate fit with evidence of rapid improvement in anti-reach performance up until middle childhood (around 8-9years of age), followed by a more gradual rate of improvement into late childhood and early adolescence. This pattern was evident on both chronometric and kinematic measures. In contrast, for children with DCD, a linear function provided the best to fit on the key metrics, with a slower rate of improvement than controls. We conclude that

  19. Attention Problems, Inhibitory Control, and Intelligence Index Overlapping Genetic Factors: A Study in 9-, 12-, and 18-Year-Old Twins

    NARCIS (Netherlands)

    Polderman, T.J.C.; de Geus, E.J.C.; Hoekstra, R.A.; Bartels, M.; van Leeuwen, M.; Verhulst, F.C.; Posthuma, D.; Boomsma, D.I.

    2009-01-01

    It is assumed that attention problems (AP) are related to impaired executive functioning. We investigated the association between AP and inhibitory control and tested to what extent the association was due to genetic factors shared with IQ. Data were available from 3 independent samples of 9-, 12-,

  20. Number conservation is related to children's prefrontal inhibitory control: an fMRI study of a piagetian task.

    Directory of Open Access Journals (Sweden)

    Nicolas Poirel

    Full Text Available Although young children can accurately determine that two rows contain the same number of coins when they are placed in a one-to-one correspondence, children younger than 7 years of age erroneously think that the longer row contains more coins when the coins in one of the rows are spread apart. To demonstrate that prefrontal inhibitory control is necessary to succeed at this task (Piaget's conservation-of-number task, we studied the relationship between the percentage of BOLD signal changes in the brain areas activated in this developmental task and behavioral performance on a Stroop task and a Backward Digit Span task. The level of activation in the right insula/inferior frontal gyrus was selectively related to inhibitory control efficiency (i.e., the Stroop task, whereas the activation in the left intraparietal sulcus (IPS was selectively related to the ability to manipulate numerical information in working memory (i.e., the Backward Digit Span task. Taken together, the results indicate that to acquire number conservation, children's brains must not only activate the reversibility of cognitive operations (supported by the IPS but also inhibit a misleading length-equal-number strategy (supported by the right insula/inferior frontal gyrus.

  1. Affect during incremental exercise: The role of inhibitory cognition, autonomic cardiac function, and cerebral oxygenation.

    Directory of Open Access Journals (Sweden)

    Weslley Quirino Alves da Silva

    Full Text Available Pleasure is a key factor for physical activity behavior in sedentary individuals. Inhibitory cognitive control may play an important role in pleasure perception while exercising, especially at high intensities. In addition, separate work suggests that autonomic regulation and cerebral hemodynamics influence the affective and cognitive responses during exercise.We investigated the effects of exercise intensity on affect, inhibitory control, cardiac autonomic function, and prefrontal cortex (PFC oxygenation.Thirty-seven sedentary young adults performed two experimental conditions (exercise and control in separate sessions in a repeated-measures design. In the exercise condition, participants performed a maximum graded exercise test on a cycle ergometer as we continuously measured oxygen consumption, heart rate variability (HRV, and PFC oxygenation. At each of 8 intensity levels we also measured inhibitory control (Stroop test, associative and dissociative thoughts (ADT, and affective/pleasure ratings. In the control condition, participants sat motionless on a cycle ergometer without active pedaling, and we collected the same measures at the same points in time as the exercise condition. We evaluated the main effects and interactions of exercise condition and intensity level for each measure using two-way repeated measures ANOVAs. Additionally, we evaluated the relationship between affect and inhibitory control, ADT, HRV, and PFC oxygenation using Pearson's correlation coefficients.For exercise intensities below and at the ventilatory threshold (VT, participants reported feeling neutral, with preservation of inhibitory control, while intensities above the VT were associated with displeasure (p<0.001, decreased inhibitory control and HRV (p<0.001, and increased PFC oxygenation (p<0.001. At the highest exercise intensity, pleasure was correlated with the low-frequency index of HRV (r = -0.34; p<0.05 and the low-frequency/high-frequency HRV ratio (r

  2. Electronic and spatial structures of water-soluble dinitrosyl iron complexes with thiol-containing ligands underlying their ability to act as nitric oxide and nitrosonium ion donors.

    Science.gov (United States)

    Vanin, Anatoly F; Burbaev, Dosymzhan Sh

    2011-01-01

    The ability of mononuclear dinitrosyl iron commplexes (M-DNICs) with thiolate ligands to act as NO donors and to trigger S-nitrosation of thiols can be explain only in the paradigm of the model of the [Fe(+)(NO(+))(2)] core ({Fe(NO)(2)}(7) according to the Enemark-Feltham classification). Similarly, the {(RS(-))(2)Fe(+)(NO(+))(2)}(+) structure describing the distribution of unpaired electron density in M-DNIC corresponds to the low-spin (S = 1/2) state with a d(7) electron configuration of the iron atom and predominant localization of the unpaired electron on MO(d(z2)) and the square planar structure of M-DNIC. On the other side, the formation of molecular orbitals of M-DNIC including orbitals of the iron atom, thiolate and nitrosyl ligands results in a transfer of electron density from sulfur atoms to the iron atom and nitrosyl ligands. Under these conditions, the positive charge on the nitrosyl ligands diminishes appreciably, the interaction of the ligands with hydroxyl ions or with thiols slows down and the hydrolysis of nitrosyl ligands and the S-nitrosating effect of the latter are not manifested. Most probably, the S-nitrosating effect of nitrosyl ligands is a result of weak binding of thiolate ligands to the iron atom under conditions favoring destabilization of M-DNIC.

  3. Plasticity of Hippocampal Excitatory-Inhibitory Balance: Missing the Synaptic Control in the Epileptic Brain

    Directory of Open Access Journals (Sweden)

    Christian Bonansco

    2016-01-01

    Full Text Available Synaptic plasticity is the capacity generated by experience to modify the neural function and, thereby, adapt our behaviour. Long-term plasticity of glutamatergic and GABAergic transmission occurs in a concerted manner, finely adjusting the excitatory-inhibitory (E/I balance. Imbalances of E/I function are related to several neurological diseases including epilepsy. Several evidences have demonstrated that astrocytes are able to control the synaptic plasticity, with astrocytes being active partners in synaptic physiology and E/I balance. Here, we revise molecular evidences showing the epileptic stage as an abnormal form of long-term brain plasticity and propose the possible participation of astrocytes to the abnormal increase of glutamatergic and decrease of GABAergic neurotransmission in epileptic networks.

  4. Acute alcohol impairs conditioning of a behavioural reward-seeking response and inhibitory control processes--implications for addictive disorders.

    Science.gov (United States)

    Loeber, Sabine; Duka, Theodora

    2009-12-01

    To investigate whether acute alcohol would affect performance of a conditioned behavioural response to obtain a reward outcome and impair performance in a task measuring inhibitory control to provide new knowledge of how the acute effects of alcohol might contribute to the transition from alcohol use to dependence. A randomized controlled between-subjects design was employed. The laboratory of experimental psychology at the University of Sussex. Thirty-two light to moderate social drinkers recruited from the undergraduate and postgraduate population. After the administration of alcohol (0.8 g/kg) or placebo participants underwent an instrumental reward-seeking procedure, with abstract stimuli serving as S+ (always predicting a win of 10 pence) and S- (always predicting a loss of 10 pence). In addition, a Stop Signal task was administered before and after the administration of alcohol. Participants of the alcohol group performed the behavioural response to obtain the reward outcome more often than placebo subjects in trials associated with loss of money. This finding was observed, although alcohol was not affecting explicit knowledge of stimulus-response outcome contingencies and acquisition of conditioned attentional and emotional responses. In addition, alcohol increased Stop Signal reaction time indicating disinhibiting effects of alcohol, and this was associated positively with response probability to the S-. These results demonstrate that alcohol is affecting inhibitory control of behavioural responses to external signals even when associated with punishment, contributing in this way to the transition from alcohol use to dependence.

  5. Age-related trends of inhibitory control in Stroop-like big–small task in 3- to 12-year-old children and young adults

    Directory of Open Access Journals (Sweden)

    Yoshifumi eIkeda

    2014-03-01

    Full Text Available Inhibitory control is the ability to suppress competing, dominant, automatic or prepotent cognitive processing at perceptual, intermediate, and output stages. Inhibitory control is a key cognitive function of typical and atypical child development. This study examined age-related trends of Stroop-like interference in 3–12-year-old children and young adults by administration of a computerized Stroop-like big–small task with reduced working memory demand. This task used a set of pictures displaying a big and small circle in black and included the same condition and the opposite condition. In the same condition, each participant was instructed to say ‘big’ when viewing the big circle and to say ‘small’ when viewing the small circle. In the opposite condition, each participant was instructed to say ‘small’ when viewing the big circle and to say ‘big’ when viewing the small circle. The opposite condition required participants to inhibit the prepotent response of saying the same, a familiar response to a perceptual stimulus. Results of this study showed that Stroop-like interference decreased markedly in children in terms of error rates and correct RT. There was no deterioration of performance occurring between the early trials and the late trials in the sessions of the day–night task. Moreover, pre-test failure rate was relatively low in this study. The Stroop-like big–small task is a useful tool to assess the development of inhibitory control in young children in that the task is easy to understand and has small working memory demand.

  6. Do Different ADHD-Related Etiological Risks Involve Specific Neuropsychological Pathways? An Analysis of Mediation Processes by Inhibitory Control and Delay Aversion

    Science.gov (United States)

    Pauli-Pott, Ursula; Dalir, Silke; Mingebach, Tanja; Roller, Alisa; Becker, Katja

    2013-01-01

    Background: Inhibitory control (IC) has been regarded as a neuropsychological basic deficit and as an endophenotype of attention deficit/hyperactivity disorder (ADHD). Implicated here are mediation processes between etiological factors and ADHD symptoms. We thus analyze whether and to what extent executive IC and delay aversion (DA; i.e.,…

  7. The Diversity of Cortical Inhibitory Synapses

    Directory of Open Access Journals (Sweden)

    Yoshiyuki eKubota

    2016-04-01

    Full Text Available The most typical and well known inhibitory action in the cortical microcircuit is a strong inhibition on the target neuron by axo-somatic synapses. However, it has become clear that synaptic inhibition in the cortex is much more diverse and complicated. Firstly, at least ten or more inhibitory non-pyramidal cell subtypes engage in diverse inhibitory functions to produce the elaborate activity characteristic of the different cortical states. Each distinct non-pyramidal cell subtype has its own independent inhibitory function. Secondly, the inhibitory synapses innervate different neuronal domains, such as axons, spines, dendrites and soma, and their IPSP size is not uniform. Thus cortical inhibition is highly complex, with a wide variety of anatomical and physiological modes. Moreover, the functional significance of the various inhibitory synapse innervation styles and their unique structural dynamic behaviors differ from those of excitatory synapses. In this review, we summarize our current understanding of the inhibitory mechanisms of the cortical microcircuit.

  8. Switches of stimulus tagging frequencies interact with the conflict-driven control of selective attention, but not with inhibitory control.

    Science.gov (United States)

    Scherbaum, Stefan; Frisch, Simon; Dshemuchadse, Maja

    2016-01-01

    Selective attention and its adaptation by cognitive control processes are considered a core aspect of goal-directed action. Often, selective attention is studied behaviorally with conflict tasks, but an emerging neuroscientific method for the study of selective attention is EEG frequency tagging. It applies different flicker frequencies to the stimuli of interest eliciting steady state visual evoked potentials (SSVEPs) in the EEG. These oscillating SSVEPs in the EEG allow tracing the allocation of selective attention to each tagged stimulus continuously over time. The present behavioral investigation points to an important caveat of using tagging frequencies: The flicker of stimuli not only produces a useful neuroscientific marker of selective attention, but interacts with the adaptation of selective attention itself. Our results indicate that RT patterns of adaptation after response conflict (so-called conflict adaptation) are reversed when flicker frequencies switch at once. However, this effect of frequency switches is specific to the adaptation by conflict-driven control processes, since we find no effects of frequency switches on inhibitory control processes after no-go trials. We discuss the theoretical implications of this finding and propose precautions that should be taken into account when studying conflict adaptation using frequency tagging in order to control for the described confounds. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Synthetic modeling chemistry of iron-sulfur clusters in nitric oxide signaling.

    Science.gov (United States)

    Fitzpatrick, Jessica; Kim, Eunsuk

    2015-08-18

    Nitric oxide (NO) is an important signaling molecule that is involved in many physiological and pathological functions. Iron-sulfur proteins are one of the main reaction targets for NO, and the [Fe-S] clusters within these proteins are converted to various iron nitrosyl species upon reaction with NO, of which dinitrosyl iron complexes (DNICs) are the most prevalent. Much progress has been made in identifying the origin of cellular DNIC generation. However, it is not well-understood which other products besides DNICs may form during [Fe-S] cluster degradation nor what effects DNICs and other degradation products can have once they are generated in cells. Even more elusive is an understanding of the manner by which cells cope with unwanted [Fe-S] modifications by NO. This Account describes our synthetic modeling efforts to identify cluster degradation products derived from the [2Fe-2S]/NO reaction in order to establish their chemical reactivity and repair chemistry. Our intent is to use the chemical knowledge that we generate to provide insight into the unknown biological consequences of cluster modification. Our recent advances in three different areas are described. First, new reaction conditions that lead to the formation of previously unrecognized products during the reaction of [Fe-S] clusters with NO are identified. Hydrogen sulfide (H2S), a gaseous signaling molecule, can be generated from the reaction between [2Fe-2S] clusters and NO in the presence of acid or formal H• (e(-)/H(+)) donors. In the presence of acid, a mononitrosyl iron complex (MNIC) can be produced as the major iron-containing product. Second, cysteine analogues can efficiently convert MNICs back to [2Fe-2S] clusters without the need for any other reagents. This reaction is possible for cysteine analogues because of their ability to labilize NO from MNICs and their capacity to undergo C-S bond cleavage, providing the necessary sulfide for [2Fe-2S] cluster formation. Lastly, unique dioxygen

  10. Neurofeedback Training Effects on Inhibitory Brain Activation in ADHD: A Matter of Learning?

    Science.gov (United States)

    Baumeister, Sarah; Wolf, Isabella; Holz, Nathalie; Boecker-Schlier, Regina; Adamo, Nicoletta; Holtmann, Martin; Ruf, Matthias; Banaschewski, Tobias; Hohmann, Sarah; Brandeis, Daniel

    2018-05-15

    Neurofeedback training (NF) is a promising non-pharmacological treatment for ADHD that has been associated with improvement of attention-deficit/hyperactivity disorder (ADHD)-related symptoms as well as changes in electrophysiological measures. However, the functional localization of neural changes following NF compared to an active control condition, and of successful learning during training (considered to be the critical mechanism for improvement), remains largely unstudied. Children with ADHD (N=16, mean age: 11.81, SD: 1.47) were randomly assigned to either slow cortical potential (SCP, n=8) based NF or biofeedback control training (electromyogram feedback, n=8) and performed a combined Flanker/NoGo task pre- and post-training. Effects of NF, compared to the active control, and of learning in transfer trials (approximating successful transfer to everyday life) were examined with respect to clinical outcome and functional magnetic resonance imaging (fMRI) changes during inhibitory control. After 20 sessions of training, children in the NF group presented reduced ADHD symptoms and increased activation in areas associated with inhibitory control compared to baseline. Subjects who were successful learners (n=9) also showed increased activation in an extensive inhibitory network irrespective of the type of training. Activation increased in an extensive inhibitory network following NF training, and following successful learning through NF and control biofeedback. Although this study was only powered to detect large effects and clearly requires replication in larger samples, the results suggest a crucial role for learning effects in biofeedback trainings. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. The effects of stereotype threat and contextual cues on alcohol users' inhibitory control.

    Science.gov (United States)

    Pennington, Charlotte R; Qureshi, Adam; Monk, Rebecca L; Heim, Derek

    2016-03-01

    Previous research indicates that users of illicit substances exhibit diminished cognitive function under stereotype threat. Advancing this research, the current study aimed to examine the effects of stereotype threat on alcohol users' inhibitory control. It also examined whether drinkers demonstrate a greater approach bias towards alcohol-related relative to neutral stimuli. Fifty-five participants were assigned randomly to a stereotype threat condition, in which they were primed with a negative stereotype linking drinking behavior to cognitive decline, or a non-threat control condition. All participants then completed a modified version of the Cued Go/No-Go Association Test that exposed participants to alcohol-related and neutral pictorial stimuli and sound cues. Stereotype threatened participants demonstrated a speed-accuracy trade off, taking significantly longer to respond to go-trials with equivalent accuracy to the control condition. They also showed reduced response accuracy to both alcohol-related and neutral stimuli in reversed instruction trials. Participants in the control condition were both more accurate and quicker to respond to alcohol-related stimuli compared to neutral stimuli. These results suggest that awareness of negative stereotypes pertaining to alcohol-related impulsivity may have a harmful effect on inhibitive cognitive performance. This may have implications for public health campaigns and for methodological designs with high levels of procedural signaling with respect to not inadvertently inducing stereotype threat and impacting impulsivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. The Neural Correlates of Self-Regulatory Fatigability During Inhibitory Control of Eye Blinking.

    Science.gov (United States)

    Abi-Jaoude, Elia; Segura, Barbara; Cho, Sang Soo; Crawley, Adrian; Sandor, Paul

    2018-05-30

    The capacity to regulate urges is an important human characteristic associated with a range of social and health outcomes. Self-regulatory capacity has been postulated to have a limited reserve, which when depleted leads to failure. The authors aimed to investigate the neural correlates of self-regulatory fatigability. Functional MRI was used to detect brain activations in 19 right-handed healthy subjects during inhibition of eye blinking, in a block design. The increase in number of blinks during blink inhibition from the first to the last block was used as covariate of interest. There was an increase in the number of eye blinks escaping inhibitory control across blink inhibition blocks, whereas there was no change in the number of eye blinks occurring during rest blocks. Inhibition of blinking activated a wide network bilaterally, including the inferior frontal gyrus, dorsolateral prefrontal cortex, dorsal anterior cingulate cortex, supplementary motor area, and caudate. Deteriorating performance was associated with activity in orbitofrontal cortex, ventromedial prefrontal cortex, rostroventral anterior cingulate cortex, precuneus, somatosensory, and parietal areas. As anticipated, effortful eye-blink control resulted in activation of prefrontal control areas and regions involved in urge and interoceptive processing. Worsening performance was associated with activations in brain areas involved in urge, as well as regions involved in motivational evaluation. These findings suggest that self-regulatory fatigability is associated with relatively less recruitment of prefrontal cortical regions involved in executive control.

  13. Cardiac Gene Expression Knockdown Using Small Inhibitory RNA-Loaded Microbubbles and Ultrasound.

    Directory of Open Access Journals (Sweden)

    Jonathan A Kopechek

    Full Text Available RNA interference has potential therapeutic value for cardiac disease, but targeted delivery of interfering RNA is a challenge. Custom designed microbubbles, in conjunction with ultrasound, can deliver small inhibitory RNA to target tissues in vivo. The efficacy of cardiac RNA interference using a microbubble-ultrasound theranostic platform has not been demonstrated in vivo. Therefore, our objective was to test the hypothesis that custom designed microbubbles and ultrasound can mediate effective delivery of small inhibitory RNA to the heart. Microbubble and ultrasound mediated cardiac RNA interference was tested in transgenic mice displaying cardiac-restricted luciferase expression. Luciferase expression was assayed in select tissues of untreated mice (n = 14. Mice received intravenous infusion of cationic microbubbles bearing small inhibitory RNA directed against luciferase (n = 9 or control RNA (n = 8 during intermittent cardiac-directed ultrasound at mechanical index of 1.6. Simultaneous echocardiography in a separate group of mice (n = 3 confirmed microbubble destruction and replenishment during treatment. Three days post treatment, cardiac luciferase messenger RNA and protein levels were significantly lower in ultrasound-treated mice receiving microbubbles loaded with small inhibitory RNA directed against luciferase compared to mice receiving microbubbles bearing control RNA (23±7% and 33±7% of control mice, p<0.01 and p = 0.03, respectively. Passive cavitation detection focused on the heart confirmed that insonification resulted in inertial cavitation. In conclusion, small inhibitory RNA-loaded microbubbles and ultrasound directed at the heart significantly reduced the expression of a reporter gene. Ultrasound-targeted destruction of RNA-loaded microbubbles may be an effective image-guided strategy for therapeutic RNA interference in cardiac disease.

  14. Effects of prenatal substance exposure on neurocognitive correlates of inhibitory control success and failure.

    Science.gov (United States)

    Roos, Leslie E; Beauchamp, Kathryn G; Pears, Katherine C; Fisher, Philip A; Berkman, Elliot T; Capaldi, Deborah

    2017-01-01

    Adolescents with prenatal substance (drug and alcohol) exposure exhibit inhibitory control (IC) deficits and aberrations in associated neural function. Nearly all research to date examines exposure to individual substances, and a minimal amount is known about the effects of heterogeneous exposure-which is more representative of population exposure levels. Using functional magnetic resonance imaging (fMRI), we investigated IC (Go/NoGo) in heterogeneously exposed (n = 7) vs. control (n = 7) at-risk adolescents (ages 13-17). The fMRI results indicated multiple IC processing differences consistent with a more immature developmental profile for exposed adolescents (Exposed  >  Nonexposed: NoGo > Go: right ventrolateral prefrontal cortex, right cuneus, and left inferior parietal lobe; NoGo > false alarm: occipital lobe; Go > false alarm: right anterior prefrontal cortex). Simple effects suggest exposed adolescents exhibited exaggerated correct trial but decreased incorrect trial activation. Results provide initial evidence that prenatal exposure across substances creates similar patterns of atypical brain activation to IC success and failure.

  15. Mechanisms underlying electrical and mechanical responses of the bovine retractor penis to inhibitory nerve stimulation and to an inhibitory extract.

    Science.gov (United States)

    Byrne, N. G.; Muir, T. C.

    1985-01-01

    The response of the bovine retractor penis (BRP) to stimulation of non-adrenergic, non-cholinergic (NANC) inhibitory nerves and to an inhibitory extract prepared from this muscle have been studied using intracellular microelectrode, sucrose gap and conventional mechanical recording techniques. Both inhibitory nerve stimulation and inhibitory extract hyperpolarized the membrane potential and relaxed spontaneous or guanethidine (3 X 10(-5) M)-induced tone. These effects were accompanied by an increase in membrane resistance. Following membrane potential displacement from an average value of -53 +/- 7 mV (n = 184; Byrne & Muir, 1984) inhibitory potentials to nerve stimulation were abolished at approximately -30 mV; there was no evidence of reversal. Displacement by inward hyperpolarizing current over the range -45 to -60 mV increased the inhibitory response to nerve stimulation and to inhibitory extract; at more negative potential values (above approximately -60 mV) the inhibitory potential decreased and was abolished (approximately -103 mV). There was no evidence of reversal. Removal of [K+]o reversibly reduced hyperpolarization to nerve stimulation and inhibitory extract. No enhancement was observed. Increasing the [K+]o to 20 mM reduced the inhibitory potential to nerve stimulation but this was restored by passive membrane hyperpolarization. Inhibitory potentials were obtained at membrane potential values exceeding that of the estimated EK (-49 mV). [Cl-]o-free or [Cl-]o-deficient solutions reduced and abolished (after some 20-25 min) the hyperpolarization produced by inhibitory nerve stimulation or inhibitory extract. The inhibitory potential amplitude following nerve stimulation was not restored by passive displacement of the membrane potential from -26 to -104 mV approximately. Ouabain (1-5 X 10(-5) M) reduced then (45-60 min later) abolished the inhibitory potential to nerve stimulation. The effects of this drug on the extract were not investigated. It is

  16. Inhibitory effects of Bacillus subtilis on plant pathogens of conservatory in high latitudes

    Science.gov (United States)

    Xue, Chun-Mei; Wang, Xue; Yang, Jia-Li; Zhang, Yue-Hua

    2018-03-01

    Researching the effect of three kinds of Bacillus and their mixed strains inhibitory on common fungal diseases of conservatory vegetables. The results showed that B. megaterium culture medium had a significant inhibition effect on Cucumber Fusarium wilt, and the inhibition rate was up to 84.36%; B. mucilaginosus and B. megaterium sterile superna-tant had an obvious inhibitory effect on brown disease of eggplant, and the inhibition rate as high as 85.49%; B. subtilis sterile supernatant had a good inhibitory effect on the spore germination of C. Fusarium wilt, and the inhibition rate was 76.83%. The results revealed that Bacillus had a significant inhibitory effect on five common fungal pathogens. Three kinds of Bacillus can be used for the prevention and control of common fungal diseases in conservatory vegetables.

  17. Deficits in inhibitory control and conflict resolution on cognitive and motor tasks in Parkinson's disease.

    Science.gov (United States)

    Obeso, Ignacio; Wilkinson, Leonora; Casabona, Enrique; Bringas, Maria Luisa; Álvarez, Mario; Álvarez, Lázaro; Pavón, Nancy; Rodríguez-Oroz, Maria-Cruz; Macías, Raúl; Obeso, Jose A; Jahanshahi, Marjan

    2011-07-01

    Recent imaging studies in healthy controls with a conditional stop signal reaction time (RT) task have implicated the subthalamic nucleus (STN) in response inhibition and the pre-supplementary motor area (pre-SMA) in conflict resolution. Parkinson's disease (PD) is characterized by striatal dopamine deficiency and overactivity of the STN and underactivation of the pre-SMA during movement. We used the conditional stop signal RT task to investigate whether PD produced similar or dissociable effects on response initiation, response inhibition and response initiation under conflict. In addition, we also examined inhibition of prepotent responses on three cognitive tasks: the Stroop, random number generation and Hayling sentence completion. PD patients were impaired on the conditional stop signal reaction time task, with response initiation both in situations with or without conflict and response inhibition all being significantly delayed, and had significantly greater difficulty in suppressing prepotent or habitual responses on the Stroop, Hayling and random number generation tasks relative to controls. These results demonstrate the existence of a generalized inhibitory deficit in PD, which suggest that PD is a disorder of inhibition as well as activation and that in situations of conflict, executive control over responses is compromised.

  18. Dynamic mobility of functional GABAA receptors at inhibitory synapses.

    Science.gov (United States)

    Thomas, Philip; Mortensen, Martin; Hosie, Alastair M; Smart, Trevor G

    2005-07-01

    Importing functional GABAA receptors into synapses is fundamental for establishing and maintaining inhibitory transmission and for controlling neuronal excitability. By introducing a binding site for an irreversible inhibitor into the GABAA receptor alpha1 subunit channel lining region that can be accessed only when the receptor is activated, we have determined the dynamics of receptor mobility between synaptic and extrasynaptic locations in hippocampal pyramidal neurons. We demonstrate that the cell surface GABAA receptor population shows no fast recovery after irreversible inhibition. In contrast, after selective inhibition, the synaptic receptor population rapidly recovers by the import of new functional entities within minutes. The trafficking pathways that promote rapid importation of synaptic receptors do not involve insertion from intracellular pools, but reflect receptor diffusion within the plane of the membrane. This process offers the synapse a rapid mechanism to replenish functional GABAA receptors at inhibitory synapses and a means to control synaptic efficacy.

  19. An NMDA Receptor-Dependent Mechanism Underlies Inhibitory Synapse Development

    Directory of Open Access Journals (Sweden)

    Xinglong Gu

    2016-01-01

    Full Text Available In the mammalian brain, GABAergic synaptic transmission provides inhibitory balance to glutamatergic excitatory drive and controls neuronal output. The molecular mechanisms underlying the development of GABAergic synapses remain largely unclear. Here, we report that NMDA-type ionotropic glutamate receptors (NMDARs in individual immature neurons are the upstream signaling molecules essential for GABAergic synapse development, which requires signaling via Calmodulin binding motif in the C0 domain of the NMDAR GluN1 subunit. Interestingly, in neurons lacking NMDARs, whereas GABAergic synaptic transmission is strongly reduced, the tonic inhibition mediated by extrasynaptic GABAA receptors is increased, suggesting a compensatory mechanism for the lack of synaptic inhibition. These results demonstrate a crucial role for NMDARs in specifying the development of inhibitory synapses, and suggest an important mechanism for controlling the establishment of the balance between synaptic excitation and inhibition in the developing brain.

  20. Mindful decision making and inhibitory control training as complementary means to decrease snack consumption.

    Science.gov (United States)

    Forman, Evan M; Shaw, Jena A; Goldstein, Stephanie P; Butryn, Meghan L; Martin, Lindsay M; Meiran, Nachshon; Crosby, Ross D; Manasse, Stephanie M

    2016-08-01

    Obesity is largely attributable to excess caloric intake, in particular from "junk" foods, including salty snack foods. Evidence suggests that neurobiological preferences to consume highly hedonic foods translate (via implicit processes) into poor eating choices, unless overturned by inhibitory mechanisms or interrupted by explicit processes. The primary aim of the current study was to test the independent and combinatory effects of a computerized inhibitory control training (ICT) and a mindful decision-making training (MDT) designed to facilitate de-automatization. We randomized 119 habitual salty snack food eaters to one of four short, training conditions: MDT, ICT, both MDT and ICT, or neither (i.e., psychoeducation). For 7 days prior to the intervention and 7 days following the intervention, participants reported on their salty snack food consumption 2 times per day, on 3 portions of their days, using a smartphone-based ecological momentary assessment system. Susceptibility to emotional eating cues was measured at baseline. Results indicated that the effect of MDT was consistent across levels of trait emotional eating, whereas the benefit of ICT was apparent only at lower levels of emotional eating. No synergistic effect of MDT and ICT was detected. These results provide qualified support for the efficacy of both types of training for decreasing hedonically-motivated eating. Moderation effects suggest that those who eat snack foods for reasons unconnected to affective experiences (i.e., lower in emotional eating) may derive benefit from a combination of ICT and MDT. Future research should investigate the additive benefit of de-automization training to standard weight loss interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Fruit Wines Inhibitory Activity Against α-Glucosidase.

    Science.gov (United States)

    Cakar, Uros; Grozdanic, Nada; Petrovic, Aleksandar; Pejin, Boris; Nastasijevic, Branislav; Markovic, Bojan; Dordevic, Brizita

    2017-01-01

    Fruit wines are well known for their profound health-promoting properties including both enzyme activations and inhibitions. They may act preventive in regard to diabetes melitus and other chronic diseases. Potential α-glucosidase inhibitory activity of fruit wines made from blueberry, black chokeberry, blackberry, raspberry and sour cherry was the subject of this study. In order to increase the alcohol content due to enriched extraction of total phenolics, sugar was added in the fruit pomace of the half of the examined fruit wine samples. Compared with acarbose used as a positive control (IC50 = 73.78 µg/mL), all fruit wine samples exhibited higher α-glucosidase inhibitory activity. Indeed, blueberry wine samples stood out, both prepared with IC50 = 24.14 µg/mL, lyophilised extract yield 3.23% and without IC50 = 46.39 µg/mL, lyophilised extract yield 2.89% and with addition of sugar before fermentation. Chlorogenic acid predominantly contributed to α-glucosidase inhibitory activity of the blueberry, black chokeberry and sour cherry wine samples. However, ellagic acid, a potent α-glucosidase inhibitor possessing a planar structure, only slightly affected the activity of the blueberry wine samples, due to the lower concentration. In addition to this, molecular docking study of chlorogenic acid pointed out the importance of binding energy (-8.5 kcal/mol) for the inhibition of the enzyme. In summary, fruit wines made from blueberry should be primarily taken into consideration as a medicinal food targeting diabetes mellitus type 2 in the early stage, if additional studies would confirm their therapeutic potential for the control of postprandial hyperglycemia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Testing food-related inhibitory control to high- and low-calorie food stimuli: Electrophysiological responses to high-calorie food stimuli predict calorie and carbohydrate intake.

    Science.gov (United States)

    Carbine, Kaylie A; Christensen, Edward; LeCheminant, James D; Bailey, Bruce W; Tucker, Larry A; Larson, Michael J

    2017-07-01

    Maintaining a healthy diet has important implications for physical and mental health. One factor that may influence diet and food consumption is inhibitory control-the ability to withhold a dominant response in order to correctly respond to environmental demands. We examined how N2 amplitude, an ERP that reflects inhibitory control processes, differed toward high- and low-calorie food stimuli and related to food intake. A total of 159 participants (81 female; M age = 23.5 years; SD = 7.6) completed two food-based go/no-go tasks (one with high-calorie and one with low-calorie food pictures as no-go stimuli) while N2 amplitude was recorded. Participants recorded food intake using the Automated Self-Administered 24-hour Dietary Recall system. Inhibiting responses toward high-calorie stimuli elicited a larger (i.e., more negative) no-go N2 amplitude; inhibiting responses toward low-calorie stimuli elicited a smaller no-go N2 amplitude. Participants were more accurate during the high-calorie than low-calorie task, but took longer to respond on go trials toward high-calorie rather than low-calorie stimuli. When controlling for age, gender, and BMI, larger high-calorie N2 difference amplitude predicted lower caloric intake (β = 0.17); low-calorie N2 difference amplitude was not related to caloric intake (β = -0.03). Exploratory analyses revealed larger high-calorie N2 difference amplitude predicted carbohydrate intake (β = 0.22), but not protein (β = 0.08) or fat (β = 0.11) intake. Results suggest that withholding responses from high-calorie foods requires increased recruitment of inhibitory control processes, which may be necessary to regulate food consumption, particularly for foods high in calories and carbohydrates. © 2017 Society for Psychophysiological Research.

  3. Inhibitory control, word retrieval and bilingual aphasia: is there a relationship?

    Directory of Open Access Journals (Sweden)

    Yasmeen Faroqi-Shah

    2014-04-01

    Responses to incongruent trials were slower than congruent for linguistic (F(1,126.3=44.9, p.05. While confrontation naming and category fluency were highly correlated (r=.77, p<.001, correlations between linguistic and non-linguistic inhibition and between word retrieval and linguistic/non-linguistic inhibition were non-significant. This large group study poses challenges to theories of bilingual advantage and the role of non-lexical inhibitory measures in word retrieval in PWA.

  4. Early life cognitive abilities and body weight: cross-sectional study of the association of inhibitory control, cognitive flexibility, and sustained attention with BMI percentiles in primary school children.

    Science.gov (United States)

    Wirt, Tamara; Schreiber, Anja; Kesztyüs, Dorothea; Steinacker, Jürgen M

    2015-01-01

    The objective of this study was to investigate the association of different cognitive abilities with children's body weight adjusted for further weight influencing sociodemographic, family, and lifestyle factors. Cross-sectional data of 498 primary school children (7.0 ± 0.6 years; 49.8% boys) participating in a health promotion programme in southwest Germany were used. Children performed a computer-based test battery (KiTAP) including an inhibitory control task (Go-Nogo paradigm), a cognitive flexibility task, and a sustained attention task. Height and weight were measured in a standardized manner and converted to BMI percentiles based on national standards. Sociodemographic features (migration background and parental education), family characteristics (parental body weight), and children's lifestyle (TV consumption, physical activity, consumption of sugar-sweetened beverages and breakfast habits) were assessed via parental questionnaire. A hierarchical regression analysis revealed inhibitory control and cognitive flexibility to be significant cognitive predictors for children's body weight. There was no association concerning sustained attention. The findings suggest that especially cognitive abilities known as executive functions (inhibitory control and cognitive flexibility) are associated with children's body weight. Future longitudinal and intervention studies are necessary to investigate the directionality of the association and the potential of integrating cognitive training in obesity prevention strategies. This trial is registered with ClinicalTrials.gov DRKS00000494.

  5. Improving oral bioavailability of resveratrol by a UDP-glucuronosyltransferase inhibitory excipient-based self-microemulsion.

    Science.gov (United States)

    Yang, Fei-Fei; Zhou, Jing; Hu, Xiao; Cong, Zhao-Qing; Liu, Chun-Yu; Pan, Rui-Le; Chang, Qi; Liu, Xin-Min; Liao, Yong-Hong

    2018-03-01

    Self-microemulsifying (SME) drug delivery system has been developed to increase oral bioavailabilities, and inhibitory excipients are capable of improving oral bioavailability by inhibiting enzyme mediated intestinal metabolism. However, the potential of enzyme inhibitory excipients containing SME in boosting resveratrol bioavailability remains largely uninvestigated. In this study, we set out to prepare SME-1 with UGT inhibitory excipients (excipients without inhibitory activities named SME-2 as control) to increase the bioavailability of RES by inhibiting intestinal metabolism. Results demonstrated that similar physicochemical properties such as size, polydistribution index and in vitro release, cellular uptake and permeability in Caco-2 cells as well as in vivo lymphatic distribution between inhibitory SME-1 and non-inhibitory SME-2 were observed. In vivo study demonstrated that the molar ratios of RES-G/RES were 7.25±0.48 and 5.06±2.42 for free drug and SME-2, respectively, and the molar ratio decreased to 0.36±0.10 in SME-1 group. Pharmacokinetic study confirmed that the inhibitory excipients containing SME demonstrated potential in increasing bioavailability of RES from 6.5% for the free RES and 12.9% for SME-2 to 76.1% in SME-1 through modulating the glucuronidation by UGT inhibitory excipients. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Inhibitory deficits for negative information in persons with major depressive disorder.

    Science.gov (United States)

    Lau, Mark A; Christensen, Bruce K; Hawley, Lance L; Gemar, Michael S; Segal, Zindel V

    2007-09-01

    Within Beck's cognitive model of depression, little is known about the mechanism(s) by which activated self-schemas result in the production of negative thoughts. Recent research has demonstrated that inhibitory dysfunction is present in depression, and this deficit is likely valence-specific. However, whether valence-specific inhibitory deficits are associated with increased negative cognition and whether such deficits are specific to depression per se remains unexamined. The authors posit the theory that inhibitory dysfunction may influence the degree to which activated self-schemas result in the production of depressive cognition. Individuals with major depressive disorder (MDD, n=43) versus healthy (n=36) and non-depressed anxious (n=32) controls were assessed on the Prose Distraction Task (PDT), a measure of cognitive inhibition, and the Stop-Signal Task (SST), a measure of motor response inhibition. These two tasks were modified in order to present emotionally valenced semantic stimuli (i.e. negative, neutral, positive). Participants with MDD demonstrated performance impairments on the PDT, which were most pronounced for negatively valenced adjectives, relative to both control groups. Moreover, these impairments correlated with self-report measures of negative thinking and rumination. Conversely, the performance of the MDD participants did not differ from either control group on the SST. Implications of these findings for understanding the mechanisms underlying the development and maintenance of depressive cognition are discussed.

  7. Growth inhibitory alkaloids from mesquite (Prosopis juliflora (Sw.) DC.) leaves.

    Science.gov (United States)

    Nakano, Hiroshi; Nakajima, Eri; Hiradate, Syuntaro; Fujii, Yoshiharu; Yamada, Kosumi; Shigemori, Hideyuki; Hasegawa, Koji

    2004-03-01

    Plant growth inhibitory alkaloids were isolated from the extract of mesquite [Prosopis juliflora (Sw.) DC.] leaves. Their chemical structures were established by ESI-MS, 1H and 13C NMR spectra analysis. The I50 value (concentration required for 50% inhibition of control) for root growth of cress (Lepidium sativum L.) seedlings was 400 microM for 3''''-oxo-juliprosopine, 500 microM for secojuliprosopinal, and 100 microM for a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine, respectively. On the other hand, the minimum concentration exhibiting inhibitory effect on shoot growth of cress seedlings was 10 microM for 3''''-oxo-juliprosopine, 100 microM for secojuliprosopinal, and 1 microM for a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine, respectively. Among these compounds, a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine exhibited the strongest inhibitory effect on the growth of cress seedlings.

  8. Intraindividual variability in inhibitory function in adults with ADHD--an ex-Gaussian approach.

    Directory of Open Access Journals (Sweden)

    Dennis Gmehlin

    Full Text Available OBJECTIVE: Attention deficit disorder (ADHD is commonly associated with inhibitory dysfunction contributing to typical behavioral symptoms like impulsivity or hyperactivity. However, some studies analyzing intraindividual variability (IIV of reaction times in children with ADHD (cADHD question a predominance of inhibitory deficits. IIV is a measure of the stability of information processing and provides evidence that longer reaction times (RT in inhibitory tasks in cADHD are due to only a few prolonged responses which may indicate deficits in sustained attention rather than inhibitory dysfunction. We wanted to find out, whether a slowing in inhibitory functioning in adults with ADHD (aADHD is due to isolated slow responses. METHODS: Computing classical RT measures (mean RT, SD, ex-Gaussian parameters of IIV (which allow a better separation of reaction time (mu, variability (sigma and abnormally slow responses (tau than classical measures as well as errors of omission and commission, we examined response inhibition in a well-established GoNogo task in a sample of aADHD subjects without medication and healthy controls matched for age, gender and education. RESULTS: We did not find higher numbers of commission errors in aADHD, while the number of omissions was significantly increased compared with controls. In contrast to increased mean RT, the distributional parameter mu did not document a significant slowing in aADHD. However, subjects with aADHD were characterized by increased IIV throughout the entire RT distribution as indicated by the parameters sigma and tau as well as the SD of reaction time. Moreover, we found a significant correlation between tau and the number of omission errors. CONCLUSIONS: Our findings question a primacy of inhibitory deficits in aADHD and provide evidence for attentional dysfunction. The present findings may have theoretical implications for etiological models of ADHD as well as more practical implications for

  9. Non-linked inhibitory gene controls a disease mimicking mutant in rice [Oryza sativa L.

    International Nuclear Information System (INIS)

    Jambhulkar, S.J.; Joshua, D.C.; Goswamy, D.G.

    2001-01-01

    A gamma ray induced disease mimicking mutant called luchai lesion was isolated in the rice variety White Luchai 112. The appearance of small light red lesions and their development continued from seedling to flowering. The lesions appeared gradually on older leaves and their uncontrolled spread eventually lead to leaf senescence. They resembled the disease spots caused by Magnaporthe grisea. However, pathological studies ruled out the possibility of pathogen mediated disease symptoms. Genetic studies revealed that lesions were governed by a dominant gene; however, their expression was suppressed in presence of a non-linked inhibitory gene. It is hypothesised that the plant cells of the mutant are able to sense inbuilt spontaneous signals leading to lesion development, but in presence of an inhibitory gene the signals are suppressed by perturbation in the signal transduction pathway [it

  10. Inhibitory effect of propolis on the development of AA amyloidosis.

    Science.gov (United States)

    Harata, Daichi; Tsuchiya, Yuya; Miyoshi, Tomoyuki; Yanai, Tokuma; Suzuki, Kazuhiko; Murakami, Tomoaki

    2018-04-01

    In the several types of amyloidoses, participation of oxidative stresses in the pathogenesis and the effect of antioxidants on amyloidosis have been reported. Meanwhile, the relationship between oxidative stresses and pathogenesis of amyloid A (AA) amyloidosis is still unclear. In this study, we used an antioxidant, Brazilian propolis, to investigate the inhibitory effects on AA amyloidosis. The results showed that AA deposition was inhibited by administration of propolis. Increased expression of antioxidant markers was detected in molecular biological examinations of mice treated with propolis. Although serum amyloid A (SAA) levels were strongly correlated with the immunoreactive area of AA deposits in the control group, the correlation was weaker in the propolis-treated groups. In addition, there were no changes in SAA levels between the control group and the propolis-treated groups. The results indicate that propolis, an antioxidant, may induce inhibitory effects against AA amyloidosis.

  11. Early Life Cognitive Abilities and Body Weight: Cross-Sectional Study of the Association of Inhibitory Control, Cognitive Flexibility, and Sustained Attention with BMI Percentiles in Primary School Children

    Directory of Open Access Journals (Sweden)

    Tamara Wirt

    2015-01-01

    Full Text Available The objective of this study was to investigate the association of different cognitive abilities with children’s body weight adjusted for further weight influencing sociodemographic, family, and lifestyle factors. Cross-sectional data of 498 primary school children (7.0 ± 0.6 years; 49.8% boys participating in a health promotion programme in southwest Germany were used. Children performed a computer-based test battery (KiTAP including an inhibitory control task (Go-Nogo paradigm, a cognitive flexibility task, and a sustained attention task. Height and weight were measured in a standardized manner and converted to BMI percentiles based on national standards. Sociodemographic features (migration background and parental education, family characteristics (parental body weight, and children’s lifestyle (TV consumption, physical activity, consumption of sugar-sweetened beverages and breakfast habits were assessed via parental questionnaire. A hierarchical regression analysis revealed inhibitory control and cognitive flexibility to be significant cognitive predictors for children’s body weight. There was no association concerning sustained attention. The findings suggest that especially cognitive abilities known as executive functions (inhibitory control and cognitive flexibility are associated with children’s body weight. Future longitudinal and intervention studies are necessary to investigate the directionality of the association and the potential of integrating cognitive training in obesity prevention strategies. This trial is registered with ClinicalTrials.gov DRKS00000494.

  12. An fMRI paradigm based on Williams inhibition test to study the neural substrates of attention and inhibitory control.

    Science.gov (United States)

    Dores, Artemisa R; Barbosa, Fernando; Carvalho, Irene P; Almeida, Isabel; Guerreiro, Sandra; da Rocha, Benedita Martins; Cunha, Gil; Castelo Branco, Miguel; de Sousa, Liliana; Castro Caldas, Alexandre

    2017-12-01

    The purpose of this study is to present an fMRI paradigm, based on the Williams inhibition test (WIT), to study attentional and inhibitory control and their neuroanatomical substrates. We present an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioral performances of healthy participants from those of individuals with acquired brain injury. Stroop and Simon tests present similarities with WIT, but this latter is more demanding. We analyze the BOLD signal in 10 healthy participants performing the WIT. The dorsolateral prefrontal cortex, the inferior prefrontal cortex, the anterior cingulate cortex, and the posterior cingulate cortex were defined for specified region of interest analysis. We additionally compare behavioral data (hits, errors, reaction times) of the healthy participants with those of eight acquired brain injury patients. Data were analyzed with GLM-based random effects and Mann-Whitney tests. Results show the involvement of the defined regions and indicate that the WIT is sensitive to brain lesions. This WIT-based block design paradigm can be used as a research methodology for behavioral and neuroimaging studies of the attentional and inhibitory components of executive functions.

  13. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents.

    Science.gov (United States)

    Domazet, Sidsel L; Tarp, Jakob; Huang, Tao; Gejl, Anne Kær; Andersen, Lars Bo; Froberg, Karsten; Bugge, Anna

    2016-01-01

    To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. The design was cross-sectional. A convenient sample of 869 sixth and seventh grade students (12-14 years) was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical activity was assessed with GT3X and GT3X+ accelerometers presented in sex-specific quartiles of mean counts per minute and mean minutes per day in moderate-to-vigorous physical activity. Active commuting and sports participation was self-reported. Mixed model regression was applied. Total physical activity level was stratified by bicycling status in order to bypass measurement error subject to the accelerometer. Non-cyclists in the 2nd quartile of counts per minute displayed a higher mathematic score, so did cyclists in the 2nd and 3rd quartile of moderate-to-vigorous physical activity relative to the least active quartile. Non-cyclists in the 3rd quartile of counts per minute had an improved reaction time and cyclists in the 2nd quartile of counts per minute and moderate-to-vigorous physical activity displayed an improved accuracy, whereas non-cyclists in the 2nd quartile of counts per minute showed an inferior accuracy relative to the least active quartile. Bicycling to school and organized sports participation were positively associated with mathematic performance. Sports participation and bicycling were positively associated with mathematic performance. Results regarding objectively measured physical activity were mixed. Although, no linear nor dose-response relationship was observed there was no indication of a higher activity level impairing the scholastic or cognitive performance.

  14. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents.

    Directory of Open Access Journals (Sweden)

    Sidsel L Domazet

    Full Text Available To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents.The design was cross-sectional. A convenient sample of 869 sixth and seventh grade students (12-14 years was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical activity was assessed with GT3X and GT3X+ accelerometers presented in sex-specific quartiles of mean counts per minute and mean minutes per day in moderate-to-vigorous physical activity. Active commuting and sports participation was self-reported. Mixed model regression was applied. Total physical activity level was stratified by bicycling status in order to bypass measurement error subject to the accelerometer.Non-cyclists in the 2nd quartile of counts per minute displayed a higher mathematic score, so did cyclists in the 2nd and 3rd quartile of moderate-to-vigorous physical activity relative to the least active quartile. Non-cyclists in the 3rd quartile of counts per minute had an improved reaction time and cyclists in the 2nd quartile of counts per minute and moderate-to-vigorous physical activity displayed an improved accuracy, whereas non-cyclists in the 2nd quartile of counts per minute showed an inferior accuracy relative to the least active quartile. Bicycling to school and organized sports participation were positively associated with mathematic performance.Sports participation and bicycling were positively associated with mathematic performance. Results regarding objectively measured physical activity were mixed. Although, no linear nor dose-response relationship was observed there was no indication of a higher activity level impairing the scholastic or cognitive

  15. Npas4 regulates excitatory-inhibitory balance within neural circuits through cell-type-specific gene programs.

    Science.gov (United States)

    Spiegel, Ivo; Mardinly, Alan R; Gabel, Harrison W; Bazinet, Jeremy E; Couch, Cameron H; Tzeng, Christopher P; Harmin, David A; Greenberg, Michael E

    2014-05-22

    The nervous system adapts to experience by inducing a transcriptional program that controls important aspects of synaptic plasticity. Although the molecular mechanisms of experience-dependent plasticity are well characterized in excitatory neurons, the mechanisms that regulate this process in inhibitory neurons are only poorly understood. Here, we describe a transcriptional program that is induced by neuronal activity in inhibitory neurons. We find that, while neuronal activity induces expression of early-response transcription factors such as Npas4 in both excitatory and inhibitory neurons, Npas4 activates distinct programs of late-response genes in inhibitory and excitatory neurons. These late-response genes differentially regulate synaptic input to these two types of neurons, promoting inhibition onto excitatory neurons while inducing excitation onto inhibitory neurons. These findings suggest that the functional outcomes of activity-induced transcriptional responses are adapted in a cell-type-specific manner to achieve a circuit-wide homeostatic response. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Length and coverage of inhibitory decision rules

    KAUST Repository

    Alsolami, Fawaz

    2012-01-01

    Authors present algorithms for optimization of inhibitory rules relative to the length and coverage. Inhibitory rules have a relation "attribute ≠ value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. Paper contains also comparison of length and coverage of inhibitory rules constructed by a greedy algorithm and by the dynamic programming algorithm. © 2012 Springer-Verlag.

  17. Inhibitory Effect of Waste Glass Powder on ASR Expansion Induced by Waste Glass Aggregate

    Directory of Open Access Journals (Sweden)

    Shuhua Liu

    2015-10-01

    Full Text Available Detailed research is carried out to ascertain the inhibitory effect of waste glass powder (WGP on alkali-silica reaction (ASR expansion induced by waste glass aggregate in this paper. The alkali reactivity of waste glass aggregate is examined by two methods in accordance with the China Test Code SL352-2006. The potential of WGP to control the ASR expansion is determined in terms of mean diameter, specific surface area, content of WGP and curing temperature. Two mathematical models are developed to estimate the inhibitory efficiency of WGP. These studies show that there is ASR risk with an ASR expansion rate over 0.2% when the sand contains more than 30% glass aggregate. However, WGP can effectively control the ASR expansion and inhibit the expansion rate induced by the glass aggregate to be under 0.1%. The two mathematical models have good simulation results, which can be used to evaluate the inhibitory effect of WGP on ASR risk.

  18. New Biflavonoids with α-Glucosidase and Pancreatic Lipase Inhibitory Activities from Boesenbergia rotunda

    Directory of Open Access Journals (Sweden)

    Nutputsorn Chatsumpun

    2017-10-01

    Full Text Available Roots of Boesenbergia rotunda (L. Mansf. are prominent ingredients in the cuisine of several Asian countries, including Thailand, Malaysia, Indonesia, India, and China. An extract prepared from the roots of this plant showed strong inhibitory activity against enzymes α-glucosidase and pancreatic lipase and was subjected to chromatographic separation to identify the active components. Three new biflavonoids of the flavanone-chalcone type (9, 12, and 13 were isolated, along with 12 known compounds. Among the 15 isolates, the three new compounds showed stronger inhibitory activity against α-glucosidase than the drug acarbose but displayed lower pancreatic lipase inhibitory effect than the drug orlistat. The results indicated the potential of B. rotunda roots as a functional food for controlling after-meal blood glucose levels.

  19. Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.

    Directory of Open Access Journals (Sweden)

    Paula Monteiro Souza

    Full Text Available The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05 tyrosinase inhibitory activity exhibiting the IC₅₀ value of 11.88 µg/mL, compared to kojic acid (IC₅₀ value of 13.14 µg/mL. Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC₅₀ value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations.

  20. α-Amylase and α-glucosidase inhibitory effects of Sclerocarya birrea ...

    African Journals Online (AJOL)

    Inhibition of intestinal α-amylase and α-glucosidase is an important strategy to control post-prandial hyperglycemia associated with type 2 diabetes mellitus. In vitro inhibitory effects of crude Sclerocarya birrea stem bark (SBSB) extracts against human urinary α-amylase and Bacillus steatothermophilus α-glucosidase were ...

  1. Why is happy-sad more difficult? Focal emotional information impairs inhibitory control in children and adults.

    Science.gov (United States)

    Kramer, Hannah J; Lagattuta, Kristin Hansen; Sayfan, Liat

    2015-02-01

    This study compared the relative difficulty of the happy-sad inhibitory control task (say "happy" for the sad face and "sad" for the happy face) against other card tasks that varied by the presence and type (focal vs. peripheral; negative vs. positive) of emotional information in a sample of 4- to 11-year-olds and adults (N = 264). Participants also completed parallel "name games" (direct labeling). All age groups made more errors and took longer to respond to happy-sad compared to other versions, and the relative difficulty of happy-sad increased with age. The happy-sad name game even posed a greater challenge than some opposite games. These data provide insight into the impact of emotions on cognitive processing across a wide age range. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  2. Dinitrosyl iron complexes with natural thiol-containing ligands in aqueous solutions: Synthesis and some physico-chemical characteristics (A methodological review).

    Science.gov (United States)

    Vanin, Anatoly F; Borodulin, Rostislav R; Mikoyan, Vasak D

    2017-06-01

    Two approaches to the synthesis of dinitrosyl iron complexes (DNIC) with glutathione and l-cysteine in aqueous solutions based on the use of gaseous NO and appropriate S-nitrosothiols, viz., S-nitrosoglutathione (GS-NO) or S-nitrosocysteine (Cys-NO), respectively, are considered. A schematic representation of a vacuum unit for generation and accumulation of gaseous NO purified from the NO 2 admixture and its application for obtaining aqueous solutions of DNIC in a Thunberg apparatus is given. To achieve this, a solution of bivalent iron in distilled water is loaded into the upper chamber of the Thunberg apparatus, while the thiol solution in an appropriate buffer (рН 7.4) is loaded into its lower chamber. Further steps, which include degassing, addition of gaseous NO, shaking of both solutions and formation of the Fe 2+ -thiol mixture, culminate in the synthesis of DNIC. The second approach consists in a stepwise addition of Fe 2+ salts and nitrite to aqueous solutions of glutathione or cysteine. In the presence of Fe 2+ and after the increase in рН to the physiological level, GS-NO or Cys-NO generated at acid media (pH nitrosonium ions (NO + ) and the peculiar characteristics of the EPR signal of their mononuclear form (M-DNIC). Copyright © 2017. Published by Elsevier Inc.

  3. Measuring inhibitory control in children and adults: brain imaging and mental chronometry

    Science.gov (United States)

    Houdé, Olivier; Borst, Grégoire

    2014-01-01

    Jean Piaget underestimated the cognitive capabilities of infants, preschoolers, and elementary schoolchildren, and overestimated the capabilities of adolescents and even adults which are often biased by illogical intuitions and overlearned strategies (i.e., “fast thinking” in Daniel Kahneman’s words). The crucial question is now to understand why, despite rich precocious knowledge about physical and mathematical principles observed over the last three decades in infants and young children, older children, adolescents and even adults are nevertheless so often bad reasoners. We propose that inhibition of less sophisticated solutions (or heuristics) by the prefrontal cortex is a domain-general executive ability that supports children’s conceptual insights associated with more advanced Piagetian stages, such as number-conservation and class inclusion. Moreover, this executive ability remains critical throughout the whole life and even adults may sometimes need “prefrontal pedagogy” in order to learn inhibiting intuitive heuristics (or biases) in deductive reasoning tasks. Here we highlight some of the discoveries from our lab in the field of cognitive development relying on two methodologies used for measuring inhibitory control: brain imaging and mental chronometry (i.e., the negative priming paradigm). We also show that this new approach opens an avenue for re-examining persistent errors in standard classroom-learning tasks. PMID:24994993

  4. Measuring inhibitory control in children and adults: brain imaging and mental chronometry

    Directory of Open Access Journals (Sweden)

    Olivier eHoudé

    2014-06-01

    Full Text Available Jean Piaget underestimated the cognitive capabilities of infants, preschoolers, and elementary schoolchildren, and overestimated the capabilities of adolescents and even adults which are often biased by illogical intuitions and overlearned strategies (i.e., fast thinking in Daniel Kahneman’s words. The crucial question is now to understand why, despite rich precocious knowledge about physical and mathematical principles observed over the last three decades in infants and young children, older children, adolescents and even adults are nevertheless so often bad reasoners. We propose that inhibition of less sophisticated solutions (or heuristics by the prefrontal cortex is a domain-general executive ability that supports children’s conceptual insights associated with more advanced Piagetian stages, such as number conservation and class inclusion. Moreover, this executive ability remains critical throughout the whole life and even adults may sometimes need prefrontal pedagogy in order to learn inhibiting intuitive heuristics (or biases in deductive reasoning tasks. Here we highlight some of the discoveries from our lab in the field of cognitive development relying on two methodologies used for measuring inhibitory control: brain imaging and mental chronometry (i.e., the negative-priming paradigm. We also show that this new approach opens an avenue for re-examining persistent errors in standard classroom-learning tasks.

  5. Measuring inhibitory control in children and adults: brain imaging and mental chronometry.

    Science.gov (United States)

    Houdé, Olivier; Borst, Grégoire

    2014-01-01

    Jean Piaget underestimated the cognitive capabilities of infants, preschoolers, and elementary schoolchildren, and overestimated the capabilities of adolescents and even adults which are often biased by illogical intuitions and overlearned strategies (i.e., "fast thinking" in Daniel Kahneman's words). The crucial question is now to understand why, despite rich precocious knowledge about physical and mathematical principles observed over the last three decades in infants and young children, older children, adolescents and even adults are nevertheless so often bad reasoners. We propose that inhibition of less sophisticated solutions (or heuristics) by the prefrontal cortex is a domain-general executive ability that supports children's conceptual insights associated with more advanced Piagetian stages, such as number-conservation and class inclusion. Moreover, this executive ability remains critical throughout the whole life and even adults may sometimes need "prefrontal pedagogy" in order to learn inhibiting intuitive heuristics (or biases) in deductive reasoning tasks. Here we highlight some of the discoveries from our lab in the field of cognitive development relying on two methodologies used for measuring inhibitory control: brain imaging and mental chronometry (i.e., the negative priming paradigm). We also show that this new approach opens an avenue for re-examining persistent errors in standard classroom-learning tasks.

  6. Brain ageing changes proteoglycan sulfation, rendering perineuronal nets more inhibitory.

    Science.gov (United States)

    Foscarin, Simona; Raha-Chowdhury, Ruma; Fawcett, James W; Kwok, Jessica C F

    2017-06-28

    Chondroitin sulfate (CS) proteoglycans in perineuronal nets (PNNs) from the central nervous system (CNS) are involved in the control of plasticity and memory. Removing PNNs reactivates plasticity and restores memory in models of Alzheimer's disease and ageing. Their actions depend on the glycosaminoglycan (GAG) chains of CS proteoglycans, which are mainly sulfated in the 4 (C4S) or 6 (C6S) positions. While C4S is inhibitory, C6S is more permissive to axon growth, regeneration and plasticity. C6S decreases during critical period closure. We asked whether there is a late change in CS-GAG sulfation associated with memory loss in aged rats. Immunohistochemistry revealed a progressive increase in C4S and decrease in C6S from 3 to 18 months. GAGs extracted from brain PNNs showed a large reduction in C6S at 12 and 18 months, increasing the C4S/C6S ratio. There was no significant change in mRNA levels of the chondroitin sulfotransferases. PNN GAGs were more inhibitory to axon growth than those from the diffuse extracellular matrix. The 18-month PNN GAGs were more inhibitory than 3-month PNN GAGs. We suggest that the change in PNN GAG sulfation in aged brains renders the PNNs more inhibitory, which lead to a decrease in plasticity and adversely affect memory.

  7. Increased beta rhythm as an indicator of inhibitory mechanisms in tourette syndrome.

    Science.gov (United States)

    Niccolai, Valentina; van Dijk, Hanneke; Franzkowiak, Stephanie; Finis, Jennifer; Südmeyer, Martin; Jonas, Melanie; Thomalla, Götz; Siebner, Hartwig Roman; Müller-Vahl, Kirsten; Münchau, Alexander; Schnitzler, Alfons; Biermann-Ruben, Katja

    2016-03-01

    Inhibitory oscillatory mechanisms subserving tic compensation have been put forward in Tourette syndrome. Modulation of the beta rhythm (15-25 Hz) as the well-established oscillatory movement execution-inhibition indicator was tested during a cognitive-motor task in patients with Tourette syndrome. Performing a Go/NoGo task, 12 patients with Tourette syndrome and 12 matched controls were recorded using whole-head magnetoencephalography. Compared to healthy participants, patients showed less beta suppression in the sensorimotor area and enhanced beta power in parieto-occipital brain regions contralaterally to the response hand. Average beta power and power gain correlated negatively with tic severity. Increased motor inhibitory as well as visuomotor attentional processes are likely to subserve tic compensation. Correlational results suggest that stronger inhibitory compensation accompanies less tic severity. © 2016 International Parkinson and Movement Disorder Society.

  8. Serum Macrophage Migration Inhibitory Factor in the Prediction of Preterm Delivery

    DEFF Research Database (Denmark)

    Pearce, Brad; Garvin, Sicily; Grove, Jakob

    2008-01-01

    Objective: Macrophage migration inhibitory factor (MIF) is a soluble mediator that helps govern the interaction between cytokines and stress hormones (e.g. cortisol). We determined if maternal MIF levels predicted subsequent preterm delivery (PTD). Study Design: A nested case-control study...

  9. Expression of macrophage migration inhibitory factor in footpad skin lesions with diabetic neuropathy.

    Science.gov (United States)

    Up Noh, Sun; Lee, Won-Young; Kim, Won-Serk; Lee, Yong-Taek; Jae Yoon, Kyung

    2018-01-01

    Background Diabetic neuropathy originating in distal lower extremities is associated with pain early in the disease course, overwhelming in the feet. However, the pathogenesis of diabetic neuropathy remains unclear. Macrophage migration inhibitory factor has been implicated in the onset of neuropathic pain and the development of diabetes. Objective of this study was to observe pain syndromes elicited in the footpad of diabetic neuropathy rat model and to assess the contributory role of migration inhibitory factor in the pathogenesis of diabetic neuropathy. Methods Diabetic neuropathy was made in Sprague Dawley rats by streptozotocin. Pain threshold was evaluated using von Frey monofilaments for 24 weeks. On comparable experiment time after streptozotocin injection, all footpads were prepared for following procedures; glutathione assay, terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling staining, immunohistochemistry staining, real-time reverse transcription polymerase chain reaction, and Western blot. Additionally, human HaCaT skin keratinocytes were treated with methylglyoxal, transfected with migration inhibitory factor/control small interfering RNA, and prepared for real-time reverse transcription polymerase chain reaction and Western blot. Results As compared to sham group, pain threshold was significantly reduced in diabetic neuropathy group, and glutathione was decreased in footpad skin, simultaneously, cell death was increased. Over-expression of migration inhibitory factor, accompanied by low expression of glyoxalase-I and intraepidermal nerve fibers, was shown on the footpad skin lesions of diabetic neuropathy. But, there was no significance in expression of neurotransmitters and inflammatory mediators such as transient receptor potential vanilloid 1, mas-related G protein coupled receptor D, nuclear factor kappa B, tumor necrosis factor-alpha, and interleukin-6 between diabetic neuropathy group and sham group. Intriguingly

  10. The frontal lobes and inhibitory function

    International Nuclear Information System (INIS)

    Konishi, Seiki

    2011-01-01

    Neuropsychological studies using traditional tasks of inhibitory functions, such as the Wisconsin card sorting test (WCST) and the Go/No-Go Task have revealed that the frontal lobe is responsible for several types of inhibitory functions. However, the detailed psychological nature of the inhibitory functions and the precise location of their critical foci within the frontal lobe remain to be investigated. Functional magnetic resonance imaging provides spatial and temporal resolution that allowed us to illuminate at least 4 frontal regions involved in inhibitory functions: the dorsolateral, ventrolateral, and rostral parts of the frontal lobe and the presupplementary motor area (preSMA). The ventrolateral part of the frontal lobe in the right hemisphere was activated during response inhibition. The preSMA in the left hemisphere was activated during inhibition of proactive interference immediately after the dimension changes of the WCST. The rostral part of the frontal lobe in the left hemisphere was activated during inhibition long after the dimension changes. The dorsolateral part of the frontal lobe in the left hemisphere was activated at the dimension changes in the first time, but not in the second time. These findings provide clues to our understanding of functional differentiation of inhibitory functions and their localization in the frontal lobe. (author)

  11. Musical training, bilingualism, and executive function: working memory and inhibitory control.

    Science.gov (United States)

    D'Souza, Annalise A; Moradzadeh, Linda; Wiseheart, Melody

    2018-01-01

    The current study investigated whether long-term experience in music or a second language is associated with enhanced cognitive functioning. Early studies suggested the possibility of a cognitive advantage from musical training and bilingualism but have failed to be replicated by recent findings. Further, each form of expertise has been independently investigated leaving it unclear whether any benefits are specifically caused by each skill or are a result of skill learning in general. To assess whether cognitive benefits from training exist, and how unique they are to each training domain, the current study compared musicians and bilinguals to each other, plus to individuals who had expertise in both skills, or neither. Young adults ( n = 153) were categorized into one of four groups: monolingual musician; bilingual musician; bilingual non-musician; and monolingual non-musician. Multiple tasks per cognitive ability were used to examine the coherency of any training effects. Results revealed that musically trained individuals, but not bilinguals, had enhanced working memory. Neither skill had enhanced inhibitory control. The findings confirm previous associations between musicians and improved cognition and extend existing evidence to show that benefits are narrower than expected but can be uniquely attributed to music compared to another specialized auditory skill domain. The null bilingual effect despite a music effect in the same group of individuals challenges the proposition that young adults are at a performance ceiling and adds to increasing evidence on the lack of a bilingual advantage on cognition.

  12. A synthesis of evidence on inhibitory control and auditory hallucinations based on the Research Domain Criteria (RDoC framework.

    Directory of Open Access Journals (Sweden)

    Johanna C. Badcock

    2014-03-01

    Full Text Available The National Institute of Mental Health initiative called the Research Domain Criteria (RDoC project aims to provide a new approach to understanding mental illness grounded in the fundamental domains of human behaviour and psychological functioning. To this end the RDoC framework encourages researchers and clinicians to think outside the [diagnostic]box, by studying symptoms, behaviours or biomarkers that cut across traditional mental illness categories. In this article we examine and discuss how the RDoC framework can improve our understanding of psychopathology by zeroing in on hallucinations- now widely recognized as a symptom that occurs in a range of clinical and non-clinical groups. We focus on a single domain of functioning - namely cognitive [inhibitory] control - and assimilate key findings structured around the basic RDoC units of analysis, which span the range from observable behaviour to molecular genetics. Our synthesis and critique of the literature provides a deeper understanding of the mechanisms involved in the emergence of auditory hallucinations, linked to the individual dynamics of inhibitory development before and after puberty; favours separate developmental trajectories for clinical and nonclinical hallucinations; yields new insights into co-occurring emotional and behavioural problems; and suggests some novel avenues for treatment.

  13. Selective synaptic targeting of the excitatory and inhibitory presynaptic organizers FGF22 and FGF7.

    Science.gov (United States)

    Terauchi, Akiko; Timmons, Kendall M; Kikuma, Koto; Pechmann, Yvonne; Kneussel, Matthias; Umemori, Hisashi

    2015-01-15

    Specific formation of excitatory and inhibitory synapses is crucial for proper functioning of the brain. Fibroblast growth factor 22 (FGF22) and FGF7 are postsynaptic-cell-derived presynaptic organizers necessary for excitatory and inhibitory presynaptic differentiation, respectively, in the hippocampus. For the establishment of specific synaptic networks, these FGFs must localize to appropriate synaptic locations - FGF22 to excitatory and FGF7 to inhibitory postsynaptic sites. Here, we show that distinct motor and adaptor proteins contribute to intracellular microtubule transport of FGF22 and FGF7. Excitatory synaptic targeting of FGF22 requires the motor proteins KIF3A and KIF17 and the adaptor protein SAP102 (also known as DLG3). By contrast, inhibitory synaptic targeting of FGF7 requires the motor KIF5 and the adaptor gephyrin. Time-lapse imaging shows that FGF22 moves with SAP102, whereas FGF7 moves with gephyrin. These results reveal the basis of selective targeting of the excitatory and inhibitory presynaptic organizers that supports their different synaptogenic functions. Finally, we found that knockdown of SAP102 or PSD95 (also known as DLG4), which impairs the differentiation of excitatory synapses, alters FGF7 localization, suggesting that signals from excitatory synapses might regulate inhibitory synapse formation by controlling the distribution of the inhibitory presynaptic organizer. © 2015. Published by The Company of Biologists Ltd.

  14. Characterization of angiotensin-converting enzyme inhibitory activity of fermented milk produced by Lactobacillus helveticus.

    Science.gov (United States)

    Chen, Yongfu; Li, Changkun; Xue, Jiangang; Kwok, Lai-yu; Yang, Jie; Zhang, Heping; Menghe, Bilige

    2015-08-01

    Hypertension affects up to 30% of the adult population in most countries. It is a known risk factor for cardiovascular diseases, including coronary heart disease, peripheral artery disease, and stroke. Owing to the increased health awareness of consumers, the application of angiotensin-converting enzyme (ACE)-inhibitory peptides produced by Lactobacillushelveticus to prevent or control high blood pressure has drawn wide attention. A total of 59 L. helveticus strains were isolated from traditional fermented dairy products and the ACE-inhibitory activity of the fermented milks produced with the isolated microorganisms was assayed. The ACE-inhibitory activity of 38 L. helveticus strains was more than 50%, and 3 strains (IMAU80872, IMAU80852, and IMAU80851) expressing the highest ACE-inhibitory activity were selected for further studies. Particularly, the gastrointestinal protease tolerance and thermostability of the ACE-inhibitory activity in the fermented milks were assessed. Based on these 2 criteria, IMAU80872 was found to be superior over the other 2 strains. Furthermore, IMAU80872 exhibited a high in vitro ACE-inhibitory activity at the following fermentation conditions: fermentation temperature at 40°C, inoculation concentration of 1×10(6) cfu/mL, and fermentation for 18h. Finally, by using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry analysis, we observed changes of the metabolome along the milk fermentation process of IMAU80872. Furthermore, 6 peptides were identified, which might have ACE-inhibitory activity. In conclusion, we identified a novel ACE-inhibitory L. helveticus strain suitable for the production of fermented milk or other functional dairy products. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. A Feedforward Inhibitory Circuit Mediated by CB1-Expressing Fast-Spiking Interneurons in the Nucleus Accumbens.

    Science.gov (United States)

    Wright, William J; Schlüter, Oliver M; Dong, Yan

    2017-04-01

    The nucleus accumbens (NAc) gates motivated behaviors through the functional output of principle medium spiny neurons (MSNs), whereas dysfunctional output of NAc MSNs contributes to a variety of psychiatric disorders. Fast-spiking interneurons (FSIs) are sparsely distributed throughout the NAc, forming local feedforward inhibitory circuits. It remains elusive how FSI-based feedforward circuits regulate the output of NAc MSNs. Here, we investigated a distinct subpopulation of NAc FSIs that express the cannabinoid receptor type-1 (CB1). Using a combination of paired electrophysiological recordings and pharmacological approaches, we characterized and compared feedforward inhibition of NAc MSNs from CB1 + FSIs and lateral inhibition from recurrent MSN collaterals. We observed that CB1 + FSIs exerted robust inhibitory control over a large percentage of nearby MSNs in contrast to local MSN collaterals that provided only sparse and weak inhibitory input to their neighboring MSNs. Furthermore, CB1 + FSI-mediated feedforward inhibition was preferentially suppressed by endocannabinoid (eCB) signaling, whereas MSN-mediated lateral inhibition was unaffected. Finally, we demonstrated that CB1 + FSI synapses onto MSNs are capable of undergoing experience-dependent long-term depression in a voltage- and eCB-dependent manner. These findings demonstrated that CB1 + FSIs are a major source of local inhibitory control of MSNs and a critical component of the feedforward inhibitory circuits regulating the output of the NAc.

  16. Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins

    Directory of Open Access Journals (Sweden)

    Marwa Yousr

    2015-12-01

    Full Text Available Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF. Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y and tryptophan (W, in sequences identified by LC-MS as WYGPD (EYGF-23 and KLSDW (EYGF-33, contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56 was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69% and IC50 value (3.35 mg/mL. The SDNRNQGY peptide (10 mg/mL had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL. In addition, YPSPV in (EYGF-33 (10 mg/mL had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

  17. Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins.

    Science.gov (United States)

    Yousr, Marwa; Howell, Nazlin

    2015-12-07

    Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

  18. Inhibitory Control of Feature Selectivity in an Object Motion Sensitive Circuit of the Retina

    Directory of Open Access Journals (Sweden)

    Tahnbee Kim

    2017-05-01

    Full Text Available Object motion sensitive (OMS W3-retinal ganglion cells (W3-RGCs in mice respond to local movements in a visual scene but remain silent during self-generated global image motion. The excitatory inputs that drive responses of W3-RGCs to local motion were recently characterized, but which inhibitory neurons suppress W3-RGCs’ responses to global motion, how these neurons encode motion information, and how their connections are organized along the excitatory circuit axis remains unknown. Here, we find that a genetically identified amacrine cell (AC type, TH2-AC, exhibits fast responses to global motion and slow responses to local motion. Optogenetic stimulation shows that TH2-ACs provide strong GABAA receptor-mediated input to W3-RGCs but only weak input to upstream excitatory neurons. Cell-type-specific silencing reveals that temporally coded inhibition from TH2-ACs cancels W3-RGC spike responses to global but not local motion stimuli and, thus, controls the feature selectivity of OMS signals sent to the brain.

  19. Integrated plasticity at inhibitory and excitatory synapses in the cerebellar circuit

    Directory of Open Access Journals (Sweden)

    Lisa eMapelli

    2015-05-01

    Full Text Available The way long-term potentiation (LTP and depression (LTD are integrated within the different synapses of brain neuronal circuits is poorly understood. In order to progress beyond the identification of specific molecular mechanisms, a system in which multiple forms of plasticity can be correlated with large-scale neural processing is required. In this paper we take as an example the cerebellar network , in which extensive investigations have revealed LTP and LTD at several excitatory and inhibitory synapses. Cerebellar LTP and LTD occur in all three main cerebellar subcircuits (granular layer, molecular layer, deep cerebellar nuclei and correspondingly regulate the function of their three main neurons: granule cells (GrCs, Purkinje cells (PCs and deep cerebellar nuclear (DCN cells. All these neurons, in addition to be excited, are reached by feed-forward and feed-back inhibitory connections, in which LTP and LTD may either operate synergistically or homeostatically in order to control information flow through the circuit. Although the investigation of individual synaptic plasticities in vitro is essential to prove their existence and mechanisms, it is insufficient to generate a coherent view of their impact on network functioning in vivo. Recent computational models and cell-specific genetic mutations in mice are shedding light on how plasticity at multiple excitatory and inhibitory synapses might regulate neuronal activities in the cerebellar circuit and contribute to learning and memory and behavioral control.

  20. Integrated plasticity at inhibitory and excitatory synapses in the cerebellar circuit.

    Science.gov (United States)

    Mapelli, Lisa; Pagani, Martina; Garrido, Jesus A; D'Angelo, Egidio

    2015-01-01

    The way long-term potentiation (LTP) and depression (LTD) are integrated within the different synapses of brain neuronal circuits is poorly understood. In order to progress beyond the identification of specific molecular mechanisms, a system in which multiple forms of plasticity can be correlated with large-scale neural processing is required. In this paper we take as an example the cerebellar network, in which extensive investigations have revealed LTP and LTD at several excitatory and inhibitory synapses. Cerebellar LTP and LTD occur in all three main cerebellar subcircuits (granular layer, molecular layer, deep cerebellar nuclei) and correspondingly regulate the function of their three main neurons: granule cells (GrCs), Purkinje cells (PCs) and deep cerebellar nuclear (DCN) cells. All these neurons, in addition to be excited, are reached by feed-forward and feed-back inhibitory connections, in which LTP and LTD may either operate synergistically or homeostatically in order to control information flow through the circuit. Although the investigation of individual synaptic plasticities in vitro is essential to prove their existence and mechanisms, it is insufficient to generate a coherent view of their impact on network functioning in vivo. Recent computational models and cell-specific genetic mutations in mice are shedding light on how plasticity at multiple excitatory and inhibitory synapses might regulate neuronal activities in the cerebellar circuit and contribute to learning and memory and behavioral control.

  1. In vivo hypotensive effect and in vitro inhibitory activity of some Cyperaceae species

    Directory of Open Access Journals (Sweden)

    Monica Lacerda Lopes Martins

    2013-12-01

    Full Text Available In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES, a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg, with acetylcholine (ACh as positive control (5 µg/kg, i.v.. The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.. Captopril (30 mg/kg was used as positive control. Bulbostylis capillaris (86.89 ± 15.20% and ERE (74.89 ± 11.95%, ERE were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%. ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.

  2. The inhibitory effect of Curcuma longa extract on telomerase activity ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-08

    Feb 8, 2010 ... curcumin, could have important effect on treatment of lung cancer. Curcumin ... study inhibitory effect of C. longa total extract on telomerase in A549 lung cancer cell line as in vitro model of ..... If A > 2× (OD of negative control), then, telomerase activity ... radiation, chemotherapy, laser therapy, photodynamic.

  3. Serum trypsin inhibitory capacity in hemodialysis patients

    International Nuclear Information System (INIS)

    Hashemi, Mohammad; Mehrabifar, Hamid; Homayooni, Fatemeh; Naderi, Mohammad; Montazerifar, Farzaneh; Ghavami, Saeid

    2009-01-01

    It has been established that overproduction of reactive oxygen species (ROS) occurs during hemodialysis causing oxidation of proteins. Alpha-1-antitrypsin is the major circulating anti-protease which contains methionine in the active site. The aim of the present study was to measure the level of serum trypsin inhibitory capacity (sTIC) in hemodialysis patients. This case-control study was performed in 52 hemodialysis patients and 49 healthy controls. sTIC was measured by enzymatic assay. The sTIC was significantly (P< 0.001) lower in hemodialysis patients (1.87 + - 0.67 micron mol/min/mL) than healthy controls (2.83 + - 0.44 micron mol/min/L). Reduction of sTIC may be due to the oxidation of methionine residue in the reactive site of alpha-1 antitrypsin. (author)

  4. Inhibitory effects of antimicrobial agents against Fusarium species.

    Science.gov (United States)

    Kawakami, Hideaki; Inuzuka, Hiroko; Hori, Nobuhide; Takahashi, Nobumichi; Ishida, Kyoko; Mochizuki, Kiyofumi; Ohkusu, Kiyofumi; Muraosa, Yasunori; Watanabe, Akira; Kamei, Katsuhiko

    2015-08-01

    We investigated the inhibitory effects of antibacterial, biocidal, and antifungal agents against Fusarium spp. Seven Fusarium spp: four F. falciforme (Fusarium solani species complex), one Fusarium spp, one Fusarium spp. (Fusarium incarnatum-equiseti species complex), and one F. napiforme (Gibberella fujikuroi species complex), isolated from eyes with fungal keratitis were used in this study. Their susceptibility to antibacterial agents: flomoxef, imipenem, gatifloxacin, levofloxacin, moxifloxacin, gentamicin, tobramycin, and Tobracin® (contained 3,000 μg/ml of tobramycin and 25 μg/ml of benzalkonium chloride (BAK), a biocidal agent: BAK, and antifungal agents: amphotericin B, pimaricin (natamycin), fluconazole, itraconazole, miconazole, voriconazole, and micafungin, was determined by broth microdilution tests. The half-maximal inhibitory concentration (IC50), 100% inhibitory concentration (IC100), and minimum inhibitory concentration (MIC) against the Fusarium isolates were determined. BAK had the highest activity against the Fusarium spp. except for the antifungal agents. Three fluoroquinolones and two aminoglycosides had inhibitory effects against the Fusarium spp. at relatively high concentrations. Tobracin® had a higher inhibitory effect against Fusarium spp. than tobramycin alone. Amphotericin B had the highest inhibitory effect against the Fusarium spp, although it had different degrees of activity against each isolate. Our findings showed that fluoroquinolones, aminoglycosides, and BAK had some degree of inhibitory effect against the seven Fusarium isolates, although these agents had considerably lower effect than amphotericin B. However, the inhibitory effects of amphotericin B against the Fusarium spp. varied for the different isolates. Further studies for more effective medications against Fusarium, such as different combinations of antibacterial, biocidal, and antifungal agents are needed. © The Author 2015. Published by Oxford University Press on

  5. Of huge mice and tiny elephants: Exploring the relationship between inhibitory processes and preschool math skills

    Directory of Open Access Journals (Sweden)

    Rebecca eMerkley

    2016-01-01

    Full Text Available The cognitive mechanisms underpinning the well-established relationship between inhibitory control and early maths skills remain unclear. We hypothesised that a specific aspect of inhibitory control drives its association with distinct math skills in very young children: the ability to ignore stimulus dimensions that are in conflict with task-relevant representations. We used an Animal Size Stroop task in which three- to six-year-olds were required to ignore the physical size of animal pictures to compare their real-life dimensions. In Experiment 1 (N=58, performance on this task correlated with standardised early mathematics achievement. In Experiment 2 (N=48, performance on the Animal Size Stroop task related to the accuracy of magnitude comparison, specifically for trials on which the physical size of dot arrays was incongruent with their numerosity. This highlights a process-oriented relationship between interference control and resolving conflict between discrete and continuous quantity, and in turn calls for further detailed empirical investigations of whether, how and why inhibitory processes matter to emerging numerical cognition.

  6. Of Huge Mice and Tiny Elephants: Exploring the Relationship Between Inhibitory Processes and Preschool Math Skills.

    Science.gov (United States)

    Merkley, Rebecca; Thompson, Jodie; Scerif, Gaia

    2015-01-01

    The cognitive mechanisms underpinning the well-established relationship between inhibitory control and early maths skills remain unclear. We hypothesized that a specific aspect of inhibitory control drives its association with distinct math skills in very young children: the ability to ignore stimulus dimensions that are in conflict with task-relevant representations. We used an Animal Size Stroop task in which 3- to 6-year-olds were required to ignore the physical size of animal pictures to compare their real-life dimensions. In Experiment 1 (N = 58), performance on this task correlated with standardized early mathematics achievement. In Experiment 2 (N = 48), performance on the Animal Size Stroop task related to the accuracy of magnitude comparison, specifically for trials on which the physical size of dot arrays was incongruent with their numerosity. This highlights a process-oriented relationship between interference control and resolving conflict between discrete and continuous quantity, and in turn calls for further detailed empirical investigations of whether, how and why inhibitory processes matter to emerging numerical cognition.

  7. From cookies to carrots; the effect of inhibitory control training on children's snack selections.

    Science.gov (United States)

    Porter, L; Bailey-Jones, C; Priudokaite, G; Allen, S; Wood, K; Stiles, K; Parvin, O; Javaid, M; Verbruggen, F; Lawrence, N S

    2018-05-01

    Children consume too much sugar and not enough fruit and vegetables, increasing their risk of adverse health outcomes. Inhibitory control training (ICT) reduces children's and adults' intake of energy-dense foods in both laboratory and real-life settings. However, no studies have yet examined whether ICT can increase healthy food choice when energy-dense options are also available. We investigated whether a food-specific Go/No-Go task could influence the food choices of children aged 4-11, as measured by a hypothetical food choice task using healthy and unhealthy food images printed on cards. Participants played either an active game (healthy foods = 100% go, unhealthy foods = 100% no-go; Studies 1 & 2), a food control game (both healthy and unhealthy foods = 50% go, 50% no-go; Studies 1 & 2) or a non-food control game (sports equipment = 100% go, technology = 100% no-go; Study 2 only) followed by the choice task. In Study 2, food card choices were also measured before training to examine change in choices. A post-training real food choice task was added to check that choices made in the card-based task were representative of choices made when faced with real healthy and unhealthy foods. Overall, the active group chose the greatest number of healthy food cards. Study 2 confirmed that this was due to increases in healthy food card choice in this group only. Active group participants chose a greater number of healthy foods in the real food choice task compared to children in the non-food control group only. The results are discussed with reference to methodological issues and the development of future healthy eating interventions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Folding of the anterior cingulate cortex partially explains inhibitory control during childhood: A longitudinal study

    Directory of Open Access Journals (Sweden)

    G. Borst

    2014-07-01

    Full Text Available Difficulties in cognitive control including inhibitory control (IC are related to the pathophysiology of several psychiatric conditions. In healthy subjects, IC efficiency in childhood is a strong predictor of academic and professional successes later in life. The dorsal anterior cingulate cortex (ACC is one of the core structures responsible for IC. Although quantitative structural characteristics of the ACC contribute to IC efficiency, the qualitative structural brain characteristics contributing to IC development are less-understood. Using anatomical magnetic resonance imaging, we investigated whether the ACC sulcal pattern at age 5, a stable qualitative characteristic of the brain determined in utero, explains IC at age 9. 18 children performed Stroop tasks at age 5 and age 9. Children with asymmetrical ACC sulcal patterns (n = 7 had better IC efficiency at age 5 and age 9 than children with symmetrical ACC sulcal patterns (n = 11. The ACC sulcal patterns appear to affect specifically IC efficiency given that the ACC sulcal patterns had no effect on verbal working memory. Our study provides the first evidence that the ACC sulcal pattern – a qualitative structural characteristic of the brain not affected by maturation and learning after birth – partially explains IC efficiency during childhood.

  9. Effects of aversive odour presentation on inhibitory control in the Stroop colour-word interference task.

    Science.gov (United States)

    Finkelmeyer, Andreas; Kellermann, Thilo; Bude, Daniela; Niessen, Thomas; Schwenzer, Michael; Mathiak, Klaus; Reske, Martina

    2010-10-18

    Due to the unique neural projections of the olfactory system, odours have the ability to directly influence affective processes. Furthermore, it has been shown that emotional states can influence various non-emotional cognitive tasks, such as memory and planning. However, the link between emotional and cognitive processes is still not fully understood. The present study used the olfactory pathway to induce a negative emotional state in humans to investigate its effect on inhibitory control performance in a standard, single-trial manual Stroop colour-word interference task. An unpleasant (H2S) and an emotionally neutral (Eugenol) odorant were presented in two separate experimental runs, both in blocks alternating with ambient air, to 25 healthy volunteers, while they performed the cognitive task. Presentation of the unpleasant odorant reduced Stroop interference by reducing the reaction times for incongruent stimuli, while the presentation of the neutral odorant had no effect on task performance. The odour-induced negative emotional state appears to facilitate cognitive processing in the task used in the present study, possibly by increasing the amount of cognitive control that is being exerted. This stands in contrast to other findings that showed impaired cognitive performance under odour-induced negative emotional states, but is consistent with models of mood-congruent processing.

  10. Effects of aversive odour presentation on inhibitory control in the Stroop colour-word interference task

    Directory of Open Access Journals (Sweden)

    Nießen Thomas

    2010-10-01

    Full Text Available Abstract Background Due to the unique neural projections of the olfactory system, odours have the ability to directly influence affective processes. Furthermore, it has been shown that emotional states can influence various non-emotional cognitive tasks, such as memory and planning. However, the link between emotional and cognitive processes is still not fully understood. The present study used the olfactory pathway to induce a negative emotional state in humans to investigate its effect on inhibitory control performance in a standard, single-trial manual Stroop colour-word interference task. An unpleasant (H2S and an emotionally neutral (Eugenol odorant were presented in two separate experimental runs, both in blocks alternating with ambient air, to 25 healthy volunteers, while they performed the cognitive task. Results Presentation of the unpleasant odorant reduced Stroop interference by reducing the reaction times for incongruent stimuli, while the presentation of the neutral odorant had no effect on task performance. Conclusions The odour-induced negative emotional state appears to facilitate cognitive processing in the task used in the present study, possibly by increasing the amount of cognitive control that is being exerted. This stands in contrast to other findings that showed impaired cognitive performance under odour-induced negative emotional states, but is consistent with models of mood-congruent processing.

  11. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents

    Science.gov (United States)

    Huang, Tao; Gejl, Anne Kær; Froberg, Karsten

    2016-01-01

    Objectives To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. Methods The design was cross-sectional. A convenient sample of 869 sixth and seventh grade students (12–14 years) was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical activity was assessed with GT3X and GT3X+ accelerometers presented in sex-specific quartiles of mean counts per minute and mean minutes per day in moderate-to-vigorous physical activity. Active commuting and sports participation was self-reported. Mixed model regression was applied. Total physical activity level was stratified by bicycling status in order to bypass measurement error subject to the accelerometer. Results Non-cyclists in the 2nd quartile of counts per minute displayed a higher mathematic score, so did cyclists in the 2nd and 3rd quartile of moderate-to-vigorous physical activity relative to the least active quartile. Non-cyclists in the 3rd quartile of counts per minute had an improved reaction time and cyclists in the 2nd quartile of counts per minute and moderate-to-vigorous physical activity displayed an improved accuracy, whereas non-cyclists in the 2nd quartile of counts per minute showed an inferior accuracy relative to the least active quartile. Bicycling to school and organized sports participation were positively associated with mathematic performance. Conclusions Sports participation and bicycling were positively associated with mathematic performance. Results regarding objectively measured physical activity were mixed. Although, no linear nor dose-response relationship was observed there was no indication of a higher activity level impairing the

  12. Modulation of Inhibitory Processing by Posttraumatic Stress Symptoms and Anxiety in a Subclinical Sample of Children.

    Science.gov (United States)

    Gindt, Morgane; Chanquoy, Lucile; Garcia, René

    2016-12-01

    In adults, pathologies of anxiety such as posttraumatic stress symptoms (PTSS) involve deficits in information processing that may reflect hypervigilance and deficient inhibitory control, specifically for negative information. However, little is known about inhibitory processing in children, particularly regarding the inhibition of emotional information. This study investigated whether children with PTSS or anxiety show impairments in executive control in an inhibition task. A total of 45 children (M age = 9.2 year, SD = 0.7, range: 8-11) completed an inhibition task involving emotional-happy, angry, and fearful-and neutral stimuli and clinical scales for PTSS and anxiety. The results indicated that the percentage of correct answers was modulated by PTSS status, particularly in the happiness task. PTSS and anxiety altered the inhibition of fearful information in children. These data suggest different types of inhibitory deficits depending on clinical symptoms, and implications are discussed. © The Author(s) 2016.

  13. Increasing arousal enhances inhibitory control in calm but not excitable dogs

    Science.gov (United States)

    Bray, Emily E.; MacLean, Evan L.; Hare, Brian A.

    2015-01-01

    The emotional-reactivity hypothesis proposes that problem-solving abilities can be constrained by temperament, within and across species. One way to test this hypothesis is with the predictions of the Yerkes-Dodson law. The law posits that arousal level, a component of temperament, affects problem solving in an inverted U-shaped relationship: optimal performance is reached at intermediate levels of arousal and impeded by high and low levels. Thus, a powerful test of the emotional-reactivity hypothesis is to compare cognitive performance in dog populations that have been bred and trained based in part on their arousal levels. We therefore compared a group of pet dogs to a group of assistance dogs bred and trained for low arousal (N = 106) on a task of inhibitory control involving a detour response. Consistent with the Yerkes-Dodson law, assistance dogs, which began the test with lower levels of baseline arousal, showed improvements when arousal was artificially increased. In contrast, pet dogs, which began the test with higher levels of baseline arousal, were negatively affected when their arousal was increased. Furthermore, the dogs’ baseline levels of arousal, as measured in their rate of tail wagging, differed by population in the expected directions. Low-arousal assistance dogs showed the most inhibition in a detour task when humans eagerly encouraged them while more highly aroused pet dogs performed worst on the same task with strong encouragement. Our findings support the hypothesis that selection on temperament can have important implications for cognitive performance. PMID:26169659

  14. Increasing arousal enhances inhibitory control in calm but not excitable dogs.

    Science.gov (United States)

    Bray, Emily E; MacLean, Evan L; Hare, Brian A

    2015-11-01

    The emotional-reactivity hypothesis proposes that problem-solving abilities can be constrained by temperament, within and across species. One way to test this hypothesis is with the predictions of the Yerkes-Dodson law. The law posits that arousal level, a component of temperament, affects problem solving in an inverted U-shaped relationship: Optimal performance is reached at intermediate levels of arousal and impeded by high and low levels. Thus, a powerful test of the emotional-reactivity hypothesis is to compare cognitive performance in dog populations that have been bred and trained based in part on their arousal levels. We therefore compared a group of pet dogs to a group of assistance dogs bred and trained for low arousal (N = 106) on a task of inhibitory control involving a detour response. Consistent with the Yerkes-Dodson law, assistance dogs, which began the test with lower levels of baseline arousal, showed improvements when arousal was artificially increased. In contrast, pet dogs, which began the test with higher levels of baseline arousal, were negatively affected when their arousal was increased. Furthermore, the dogs' baseline levels of arousal, as measured in their rate of tail wagging, differed by population in the expected directions. Low-arousal assistance dogs showed the most inhibition in a detour task when humans eagerly encouraged them, while more highly aroused pet dogs performed worst on the same task with strong encouragement. Our findings support the hypothesis that selection on temperament can have important implications for cognitive performance.

  15. Electronic and Spatial Structures of Water-Soluble Dinitrosyl Iron Complexes with Thiol-Containing Ligands Underlying Their Ability to Act as Nitric Oxide and Nitrosonium Ion Donors

    OpenAIRE

    Vanin, Anatoly F.; Burbaev, Dosymzhan Sh.

    2011-01-01

    The ability of mononuclear dinitrosyl iron commplexes (M-DNICs) with thiolate ligands to act as NO donors and to trigger S-nitrosation of thiols can be explain only in the paradigm of the model of the [Fe+(NO+)2] core ({Fe(NO)2}7 according to the Enemark-Feltham classification). Similarly, the {(RS−)2Fe+(NO+)2}+ structure describing the distribution of unpaired electron density in M-DNIC corresponds to the low-spin (S = 1/2) state with a d7 electron configuration of the iron atom and predomin...

  16. Synaptic reorganization of inhibitory hilar interneuron circuitry after traumatic brain injury in mice

    Science.gov (United States)

    Hunt, Robert F.; Scheff, Stephen W.; Smith, Bret N.

    2011-01-01

    Functional plasticity of synaptic networks in the dentate gyrus has been implicated in the development of posttraumatic epilepsy and in cognitive dysfunction after traumatic brain injury, but little is known about potentially pathogenic changes in inhibitory circuits. We examined synaptic inhibition of dentate granule cells and excitability of surviving GABAergic hilar interneurons 8–13 weeks after cortical contusion brain injury in transgenic mice that express enhanced green fluorescent protein in a subpopulation of inhibitory neurons. Whole-cell voltage-clamp recordings in granule cells revealed a reduction in spontaneous and miniature IPSC frequency after head injury; no concurrent change in paired-pulse ratio was found in granule cells after paired electrical stimulation of the hilus. Despite reduced inhibitory input to granule cells, action potential and EPSC frequencies were increased in hilar GABA neurons from slices ipsilateral to the injury, versus those from control or contralateral slices. Further, increased excitatory synaptic activity was detected in hilar GABA neurons ipsilateral to the injury after glutamate photostimulation of either the granule cell or CA3 pyramidal cell layers. Together, these findings suggest that excitatory drive to surviving hilar GABA neurons is enhanced by convergent input from both pyramidal and granule cells, but synaptic inhibition of granule cells is not fully restored after injury. This rewiring of circuitry regulating hilar inhibitory neurons may reflect an important compensatory mechanism, but it may also contribute to network destabilization by increasing the relative impact of surviving individual interneurons in controlling granule cell excitability in the posttraumatic dentate gyrus. PMID:21543618

  17. [Chemical Constituents from Leaves of Hibiscus syriacus and Their α-Glucosidase Inhibitory Activities].

    Science.gov (United States)

    Wei, Qiang; Ji, Xiao-ying; Xu, Fei; Li, Qian-rong; Yin, Hao

    2015-05-01

    To study the chemical constituents from Hibiscus syriacus leaves and their α-glucosidase inhibitory activities. Column chromatography including macroporous resins, silica gel and Sephadex LH-20 were used for the isolation and purification of all compounds. Spectroscopic methods including physical and chemical properties, 1H-NMR and 13C-NMR were used for the identification of structures. Their α-glucosidase inhibitory activities were detected by a 96-well microplate. 15 compounds were isolated and identified as β-sitosterol(1), β-daucostero (2), β-amyrin (3), oleanolic acid (4), stigmast-4-en-3-one (5), friedelin (6), syriacusin A (7), kaempferol (8), isovitexin (9), vitexin (10), apigenin (11), apigenin-7-O-β-D-glucopyranoside (12), luteolin-7-O-β-D-glucopyranoside (13), vitexin-7-O-β-D-glucopyranoside (14) and rutin (15). All the compounds are isolated from the leaves of Hibiscus syriacus for the first time. Taking acarbose as positive control, the α-glucosidase inhibitory activities of 15 compounds were evaluated. Compounds 7 and 9 have shown strong α-glucosidase inhibitory activities with IC50 of 39.03 ± 0.38 and 32.12 ± 0.62 mg/L, inhibition ratio of 94.95% and 97.15%, respectively.

  18. Top-down modulation on perceptual decision with balanced inhibition through feedforward and feedback inhibitory neurons.

    Directory of Open Access Journals (Sweden)

    Cheng-Te Wang

    Full Text Available Recent physiological studies have shown that neurons in various regions of the central nervous systems continuously receive noisy excitatory and inhibitory synaptic inputs in a balanced and covaried fashion. While this balanced synaptic input (BSI is typically described in terms of maintaining the stability of neural circuits, a number of experimental and theoretical studies have suggested that BSI plays a proactive role in brain functions such as top-down modulation for executive control. Two issues have remained unclear in this picture. First, given the noisy nature of neuronal activities in neural circuits, how do the modulatory effects change if the top-down control implements BSI with different ratios between inhibition and excitation? Second, how is a top-down BSI realized via only excitatory long-range projections in the neocortex? To address the first issue, we systematically tested how the inhibition/excitation ratio affects the accuracy and reaction times of a spiking neural circuit model of perceptual decision. We defined an energy function to characterize the network dynamics, and found that different ratios modulate the energy function of the circuit differently and form two distinct functional modes. To address the second issue, we tested BSI with long-distance projection to inhibitory neurons that are either feedforward or feedback, depending on whether these inhibitory neurons do or do not receive inputs from local excitatory cells, respectively. We found that BSI occurs in both cases. Furthermore, when relying on feedback inhibitory neurons, through the recurrent interactions inside the circuit, BSI dynamically and automatically speeds up the decision by gradually reducing its inhibitory component in the course of a trial when a decision process takes too long.

  19. Top-down modulation on perceptual decision with balanced inhibition through feedforward and feedback inhibitory neurons.

    Science.gov (United States)

    Wang, Cheng-Te; Lee, Chung-Ting; Wang, Xiao-Jing; Lo, Chung-Chuan

    2013-01-01

    Recent physiological studies have shown that neurons in various regions of the central nervous systems continuously receive noisy excitatory and inhibitory synaptic inputs in a balanced and covaried fashion. While this balanced synaptic input (BSI) is typically described in terms of maintaining the stability of neural circuits, a number of experimental and theoretical studies have suggested that BSI plays a proactive role in brain functions such as top-down modulation for executive control. Two issues have remained unclear in this picture. First, given the noisy nature of neuronal activities in neural circuits, how do the modulatory effects change if the top-down control implements BSI with different ratios between inhibition and excitation? Second, how is a top-down BSI realized via only excitatory long-range projections in the neocortex? To address the first issue, we systematically tested how the inhibition/excitation ratio affects the accuracy and reaction times of a spiking neural circuit model of perceptual decision. We defined an energy function to characterize the network dynamics, and found that different ratios modulate the energy function of the circuit differently and form two distinct functional modes. To address the second issue, we tested BSI with long-distance projection to inhibitory neurons that are either feedforward or feedback, depending on whether these inhibitory neurons do or do not receive inputs from local excitatory cells, respectively. We found that BSI occurs in both cases. Furthermore, when relying on feedback inhibitory neurons, through the recurrent interactions inside the circuit, BSI dynamically and automatically speeds up the decision by gradually reducing its inhibitory component in the course of a trial when a decision process takes too long.

  20. Working memory and inhibitory control across the life span: Intrusion errors in the Reading Span Test.

    Science.gov (United States)

    Robert, Christelle; Borella, Erika; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

    2009-04-01

    The aim of this study was to examine to what extent inhibitory control and working memory capacity are related across the life span. Intrusion errors committed by children and younger and older adults were investigated in two versions of the Reading Span Test. In Experiment 1, a mixed Reading Span Test with items of various list lengths was administered. Older adults and children recalled fewer correct words and produced more intrusions than did young adults. Also, age-related differences were found in the type of intrusions committed. In Experiment 2, an adaptive Reading Span Test was administered, in which the list length of items was adapted to each individual's working memory capacity. Age groups differed neither on correct recall nor on the rate of intrusions, but they differed on the type of intrusions. Altogether, these findings indicate that the availability of attentional resources influences the efficiency of inhibition across the life span.

  1. Cumulative risk exposure moderates the association between parasympathetic reactivity and inhibitory control in preschool-age children.

    Science.gov (United States)

    Giuliano, Ryan J; Roos, Leslie E; Farrar, Jessica D; Skowron, Elizabeth A

    2018-04-01

    A child's cumulative risk for early exposure to stress has been linked to alterations of self-regulation outcomes, including neurobiological correlates of inhibitory control (IC). We examined whether children's ability to engage the parasympathetic nervous system impacts how risk affects IC. Children ages 3-5 years completed two laboratory measures of IC while respiratory sinus arrhythmia (RSA) was measured, indexing parasympathetic activity. Children with greater risk demonstrated lower IC; risk also moderated associations between RSA reactivity and IC. For children with less risk, greater RSA withdrawal during IC tasks was associated with better IC. In contrast, greater risk was associated with poor IC, regardless of RSA withdrawal. Effects of risk were more pronounced for cumulative than individual measures. Results suggest that cumulative risk exposure disrupts connectivity between physiological and behavioral components of self-regulation in early childhood. Parasympathetic withdrawal to cognitive tasks may be less relevant for performance in developmental samples experiencing greater life stress. © 2018 Wiley Periodicals, Inc.

  2. Role of inhibitory feedback for information processing in thalamocortical circuits

    International Nuclear Information System (INIS)

    Mayer, Joerg; Schuster, Heinz Georg; Claussen, Jens Christian

    2006-01-01

    The information transfer in the thalamus is blocked dynamically during sleep, in conjunction with the occurrence of spindle waves. In order to describe the dynamic mechanisms which control the sensory transfer of information, it is necessary to have a qualitative model for the response properties of thalamic neurons. As the theoretical understanding of the mechanism remains incomplete, we analyze two modeling approaches for a recent experiment by Le Masson et al. [Nature (London) 417, 854 (2002)] on the thalamocortical loop. We use a conductance based model in order to motivate an extension of the Hindmarsh-Rose model, which mimics experimental observations of Le Masson et al. Typically, thalamic neurons posses two different firing modes, depending on their membrane potential. At depolarized potentials, the cells fire in a single spike mode and relay synaptic inputs in a one-to-one manner to the cortex. If the cell gets hyperpolarized, T-type calcium currents generate burst-mode firing which leads to a decrease in the spike transfer. In thalamocortical circuits, the cell membrane gets hyperpolarized by recurrent inhibitory feedback loops. In the case of reciprocally coupled excitatory and inhibitory neurons, inhibitory feedback leads to metastable self-sustained oscillations, which mask the incoming input, and thereby reduce the information transfer significantly

  3. False belief understanding and cool inhibitory control in 3-and 4-year-old Italian children

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    Francesca eBellagamba

    2015-06-01

    Full Text Available During preschool years, major developments occur in both executive function and theory of mind (ToM, and several studies have demonstrated a correlation between these processes. Research on the development of inhibitory control (IC has distinguished between more cognitive, cool aspects of self-control, measured by conflict tasks, that require inhibiting an habitual response to generate an arbitrary one, and hot, affective aspects, such as affective decision making, measured by delay tasks, that require inhibition of a prepotent response. The aim of this study was to investigate the relations between 3- and 4-year-olds’ performance on a task measuring false belief understanding, the most widely used index of ToM in preschoolers, and two tasks measuring cognitive versus affective aspects of IC. To this end, we tested 101 Italian preschool children in three tasks: (a the Unexpected Content False Belief task, (b the Conflict task (a simplified version of the Day-Night Stroop task, and (c the Delay task. Children’s receptive vocabulary was assessed by the Peabody Picture Vocabulary test. Children’s performance in the False Belief task was significantly related only to performance in the Conflict task, controlling for vocabulary and age. Importantly, children’s performance in the Conflict task did not significantly correlate with their performance in the Delay task, suggesting that these tasks measure different components of IC. The dissociation between the Conflict and the Delay task may indicate that monitoring and regulating a cool process (as flexible categorization may involve different abilities than monitoring and regulating a hot process (not touching an available and highly attractive stimulus. Moreover, our findings support the view that cool aspects of IC and ToM are interrelated, extending to an Italian sample of children previous findings on an association between self-control and ToM.

  4. Whisker Deprivation Drives Two Phases of Inhibitory Synapse Weakening in Layer 4 of Rat Somatosensory Cortex.

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    Melanie A Gainey

    Full Text Available Inhibitory synapse development in sensory neocortex is experience-dependent, with sustained sensory deprivation yielding fewer and weaker inhibitory synapses. Whether this represents arrest of synapse maturation, or a more complex set of processes, is unclear. To test this, we measured the dynamics of inhibitory synapse development in layer 4 of rat somatosensory cortex (S1 during continuous whisker deprivation from postnatal day 7, and in age-matched controls. In deprived columns, spontaneous miniature inhibitory postsynaptic currents (mIPSCs and evoked IPSCs developed normally until P15, when IPSC amplitude transiently decreased, recovering by P16 despite ongoing deprivation. IPSCs remained normal until P22, when a second, sustained phase of weakening began. Delaying deprivation onset by 5 days prevented the P15 weakening. Both early and late phase weakening involved measurable reduction in IPSC amplitude relative to prior time points. Thus, deprivation appears to drive two distinct phases of active IPSC weakening, rather than simple arrest of synapse maturation.

  5. When this means that: the role of working memory and inhibitory control in children's understanding of representations.

    Science.gov (United States)

    Astle, Andrea; Kamawar, Deepthi; Vendetti, Corrie; Podjarny, Gal

    2013-10-01

    We investigated cognitive skills that contribute to 4-year-olds' understanding of representations. In our main task, children used representations on a perspective line drawing to find stickers hidden in a model room. To compare the contributions made by various cognitive skills with children's understanding of different types of representations, we manipulated the resemblance between the representations and their referents. Our results indicate that when representations are iconic (i.e., look like their referents), children have very little difficulty with the task. Controlling for performance on this baseline version of the task, we found that specific cognitive skills are differentially predictive of performance when using arbitrary and conflicting representations (i.e., symbols). When the representation was arbitrarily linked to the sticker, performance was related to phonological and visuospatial working memory. When the representation matched the color of an alternate sticker (thereby conflicting with the desired sticker), performance was related to phonological working memory and inhibitory control. We discuss the role that different cognitive skills play in representational understanding as a function of the nature of the representation-referent relation. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Recruitment of activation receptors at inhibitory NK cell immune synapses.

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    Nicolas Schleinitz

    2008-09-01

    Full Text Available Natural killer (NK cell activation receptors accumulate by an actin-dependent process at cytotoxic immune synapses where they provide synergistic signals that trigger NK cell effector functions. In contrast, NK cell inhibitory receptors, including members of the MHC class I-specific killer cell Ig-like receptor (KIR family, accumulate at inhibitory immune synapses, block actin dynamics, and prevent actin-dependent phosphorylation of activation receptors. Therefore, one would predict inhibition of actin-dependent accumulation of activation receptors when inhibitory receptors are engaged. By confocal imaging of primary human NK cells in contact with target cells expressing physiological ligands of NK cell receptors, we show here that this prediction is incorrect. Target cells included a human cell line and transfected Drosophila insect cells that expressed ligands of NK cell activation receptors in combination with an MHC class I ligand of inhibitory KIR. The two NK cell activation receptors CD2 and 2B4 accumulated and co-localized with KIR at inhibitory immune synapses. In fact, KIR promoted CD2 and 2B4 clustering, as CD2 and 2B4 accumulated more efficiently at inhibitory synapses. In contrast, accumulation of KIR and of activation receptors at inhibitory synapses correlated with reduced density of the integrin LFA-1. These results imply that inhibitory KIR does not prevent CD2 and 2B4 signaling by blocking their accumulation at NK cell immune synapses, but by blocking their ability to signal within inhibitory synapses.

  7. New players tip the scales in the balance between excitatory and inhibitory synapses

    Directory of Open Access Journals (Sweden)

    El-Husseini Alaa

    2005-03-01

    Full Text Available Abstract Synaptogenesis is a highly controlled process, involving a vast array of players which include cell adhesion molecules, scaffolding and signaling proteins, neurotransmitter receptors and proteins associated with the synaptic vesicle machinery. These molecules cooperate in an intricate manner on both the pre- and postsynaptic sides to orchestrate the precise assembly of neuronal contacts. This is an amazing feat considering that a single neuron receives tens of thousands of synaptic inputs but virtually no mismatch between pre- and postsynaptic components occur in vivo. One crucial aspect of synapse formation is whether a nascent synapse will develop into an excitatory or inhibitory contact. The tight control of a balance between the types of synapses formed regulates the overall neuronal excitability, and is thus critical for normal brain function and plasticity. However, little is known about how this balance is achieved. This review discusses recent findings which provide clues to how neurons may control excitatory and inhibitory synapse formation, with focus on the involvement of the neuroligin family and PSD-95 in this process.

  8. Decorrelation of Neural-Network Activity by Inhibitory Feedback

    Science.gov (United States)

    Einevoll, Gaute T.; Diesmann, Markus

    2012-01-01

    Correlations in spike-train ensembles can seriously impair the encoding of information by their spatio-temporal structure. An inevitable source of correlation in finite neural networks is common presynaptic input to pairs of neurons. Recent studies demonstrate that spike correlations in recurrent neural networks are considerably smaller than expected based on the amount of shared presynaptic input. Here, we explain this observation by means of a linear network model and simulations of networks of leaky integrate-and-fire neurons. We show that inhibitory feedback efficiently suppresses pairwise correlations and, hence, population-rate fluctuations, thereby assigning inhibitory neurons the new role of active decorrelation. We quantify this decorrelation by comparing the responses of the intact recurrent network (feedback system) and systems where the statistics of the feedback channel is perturbed (feedforward system). Manipulations of the feedback statistics can lead to a significant increase in the power and coherence of the population response. In particular, neglecting correlations within the ensemble of feedback channels or between the external stimulus and the feedback amplifies population-rate fluctuations by orders of magnitude. The fluctuation suppression in homogeneous inhibitory networks is explained by a negative feedback loop in the one-dimensional dynamics of the compound activity. Similarly, a change of coordinates exposes an effective negative feedback loop in the compound dynamics of stable excitatory-inhibitory networks. The suppression of input correlations in finite networks is explained by the population averaged correlations in the linear network model: In purely inhibitory networks, shared-input correlations are canceled by negative spike-train correlations. In excitatory-inhibitory networks, spike-train correlations are typically positive. Here, the suppression of input correlations is not a result of the mere existence of correlations between

  9. Prefrontal activation during inhibitory control measured by near-infrared spectroscopy for differentiating between autism spectrum disorders and attention deficit hyperactivity disorder in adults

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    Ayaka Ishii-Takahashi

    2014-01-01

    Full Text Available The differential diagnosis of autism spectrum disorders (ASDs and attention deficit hyperactivity disorder (ADHD based solely on symptomatic and behavioral assessments can be difficult, even for experts. Thus, the development of a neuroimaging marker that differentiates ASDs from ADHD would be an important contribution to this field. We assessed the differences in prefrontal activation between adults with ASDs and ADHD using an entirely non-invasive and portable neuroimaging tool, near-infrared spectroscopy. This study included 21 drug-naïve adults with ASDs, 19 drug-naïve adults with ADHD, and 21 healthy subjects matched for age, sex, and IQ. Oxygenated hemoglobin concentration changes in the prefrontal cortex were assessed during a stop signal task and a verbal fluency task. During the stop signal task, compared to the control group, the ASDs group exhibited lower activation in a broad prefrontal area, whereas the ADHD group showed underactivation of the right premotor area, right presupplementary motor area, and bilateral dorsolateral prefrontal cortices. Significant differences were observed in the left ventrolateral prefrontal cortex between the ASDs and ADHD groups during the stop signal task. The leave-one-out cross-validation method using mean oxygenated hemoglobin changes yielded a classification accuracy of 81.4% during inhibitory control. These results were task specific, as the brain activation pattern observed during the verbal fluency task did not differentiate the ASDs and ADHD groups significantly. This study therefore provides evidence of a difference in left ventrolateral prefrontal activation during inhibitory control between adults with ASDs and ADHD. Thus, near-infrared spectroscopy may be useful as an auxiliary tool for the differential diagnosis of such developmental disorders.

  10. Somatostatin-expressing inhibitory interneurons in cortical circuits

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    Iryna Yavorska

    2016-09-01

    Full Text Available Cortical inhibitory neurons exhibit remarkable diversity in their morphology, connectivity, and synaptic properties. Here, we review the function of somatostatin-expressing (SOM inhibitory interneurons, focusing largely on sensory cortex. SOM neurons also comprise a number of subpopulations that can be distinguished by their morphology, input and output connectivity, laminar location, firing properties, and expression of molecular markers. Several of these classes of SOM neurons show unique dynamics and characteristics, such as facilitating synapses, specific axonal projections, intralaminar input, and top-down modulation, which suggest possible computational roles. SOM cells can be differentially modulated by behavioral state depending on their class, sensory system, and behavioral paradigm. The functional effects of such modulation have been studied with optogenetic manipulation of SOM cells, which produces effects on learning and memory, task performance, and the integration of cortical activity. Different classes of SOM cells participate in distinct disinhibitory circuits with different inhibitory partners and in different cortical layers. Through these disinhibitory circuits, SOM cells help encode the behavioral relevance of sensory stimuli by regulating the activity of cortical neurons based on subcortical and intracortical modulatory input. Associative learning leads to long-term changes in the strength of connectivity of SOM cells with other neurons, often influencing the strength of inhibitory input they receive. Thus despite their heterogeneity and variability across cortical areas, current evidence shows that SOM neurons perform unique neural computations, forming not only distinct molecular but also functional subclasses of cortical inhibitory interneurons.

  11. Inhibitory effects of silver zeolite on in vitro growth of fish egg pathogen, Saprolegnia sp.

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    Seyed Ali Johari

    2014-05-01

    Full Text Available Objective: To investigate the effects of powdered silver zeolite (SZ on the in vitro growth of the fish pathogen Saprolegnia sp. Methods: The antifungal activity of SZ was evaluated by determining the minimum inhibitory concentrations using two-fold serial dilutions of powdered SZ in a glucose yeast extract agar at 22 °C. The growth of Saprolegnia sp. on the SZ agar treatments was compared to that on SZ-free agar controls. Results: The results showed that SZ had an inhibitory effect on the in vitro growth of the tested fungi. The minimum inhibitory concentration of SZ for Saprolegnia sp. was also calculated at 600 mg/L, which is equal to 0.06 percent. Conclusions: SZ is a potential good candidate to replace teratogenic and toxic agents, such as malachite green in aquaculture systems.

  12. Virus encoded MHC-like decoys diversify the inhibitory KIR repertoire.

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    Paola Carrillo-Bustamante

    Full Text Available Natural killer (NK cells are circulating lymphocytes that play an important role in the control of viral infections and tumors. Their functions are regulated by several activating and inhibitory receptors. A subset of these receptors in human NK cells are the killer immunoglobulin-like receptors (KIRs, which interact with the highly polymorphic MHC class I molecules. One important function of NK cells is to detect cells that have down-regulated MHC expression (missing-self. Because MHC molecules have non polymorphic regions, their expression could have been monitored with a limited set of monomorphic receptors. Surprisingly, the KIR family has a remarkable genetic diversity, the function of which remains poorly understood. The mouse cytomegalovirus (MCMV is able to evade NK cell responses by coding "decoy" molecules that mimic MHC class I. This interaction was suggested to have driven the evolution of novel NK cell receptors. Inspired by the MCMV system, we develop an agent-based model of a host population infected with viruses that are able to evolve MHC down-regulation and decoy molecules. Our simulations show that specific recognition of MHC class I molecules by inhibitory KIRs provides excellent protection against viruses evolving decoys, and that the diversity of inhibitory KIRs will subsequently evolve as a result of the required discrimination between host MHC molecules and decoy molecules.

  13. Organizers of inhibitory synapses come of age.

    Science.gov (United States)

    Krueger-Burg, Dilja; Papadopoulos, Theofilos; Brose, Nils

    2017-08-01

    While the postsynaptic density of excitatory synapses is known to encompass a highly complex molecular machinery, the equivalent organizational structure of inhibitory synapses has long remained largely undefined. In recent years, however, substantial progress has been made towards identifying the full complement of organizational proteins present at inhibitory synapses, including submembranous scaffolds, intracellular signaling proteins, transsynaptic adhesion proteins, and secreted factors. Here, we summarize these findings and discuss future challenges in assigning synapse-specific functions to the newly discovered catalog of proteins, an endeavor that will depend heavily on newly developed technologies such as proximity biotinylation. Further advances are made all the more essential by growing evidence that links inhibitory synapses to psychiatric and neurological disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Lanostane triterpenes from the mushroom Ganoderma resinaceum and their inhibitory activities against α-glucosidase.

    Science.gov (United States)

    Chen, Xian-Qiang; Zhao, Jing; Chen, Ling-Xiao; Wang, Shen-Fei; Wang, Ying; Li, Shao-Ping

    2018-05-01

    Eighteen previously undescribed lanostane triterpenes and thirty known analogues were obtained from the fruiting bodies of Ganoderma resinaceum. Resinacein C was isolated from a natural source for the first time. The structures of all the above compounds were elucidated by extensive spectroscopic analysis and comparisons of their spectroscopic data with those reported in the literature. Furthermore, in an in vitro assay, Resinacein C, ganoderic acid Y, lucialdehyde C, 7-oxo-ganoderic acid Z 3 , 7-oxo-ganoderic acid Z, and lucidadiol showed strong inhibitory effects against α-glucosidase compared with the positive control drug acarbose. The structure-activity relationships of ganoderma triterpenes on α-glucosidase inhibition showed that the C-24/C-25 double bond is necessary for α-glucosidase inhibitory activity. Moreover, the carboxylic acid group at C-26 and the hydroxy group at C-15 play important roles in enhancing inhibitory effects of these triterpenes. Copyright © 2018. Published by Elsevier Ltd.

  15. ELEVATED CIRCULATING LEVELS OF MACROPHAGE MIGRATION INHIBITORY FACTOR IN POLYCYSTIC OVARY SYNDROME

    OpenAIRE

    González, Frank; Rote, Neal S.; Minium, Judi; Weaver, Amy L.; Kirwan, John P.

    2010-01-01

    Women with Polycystic Ovary Syndrome (PCOS) have chronic low level inflammation which can increase the risk of atherogenesis. We evaluated the status of circulating macrophage migration inhibitory factor (MIF), a proinflammatory cytokine involved in atherogenesis, in women with PCOS and weight-matched controls. Two-way analysis of variance models adjusted for age were fit to evaluate the effect of PCOS status (PCOS vs. controls) and weight-class (obese vs. lean) on MIF and other parameters. M...

  16. Effects of Different Working Modes of Ultrasound on Structural Characteristics of Zein and ACE Inhibitory Activity of Hydrolysates

    Directory of Open Access Journals (Sweden)

    Xiaofeng Ren

    2017-01-01

    Full Text Available Ultrasound was used as a new technology to pretreat protein prior to proteolysis to improve enzymolysis efficiency. The effects of different working modes of ultrasound on the angiotensin I-converting enzyme (ACE inhibitory activity of zein hydrolysates and the structural characteristics of zein were investigated. The solubility, surface hydrophobicity (H0, ultraviolet-visible (UV-Vis spectra, intrinsic fluorescence spectra, and circular dichroism (CD spectra of zein pretreated with ultrasound were determined. All ultrasound pretreatments significantly improved the ACE inhibitory activity of zein hydrolysates (p<0.05. The highest ACE inhibitory activity, representing an increase of 99.21% over the control, was obtained with dual sweeping frequency ultrasound of 33±2 and 68±2 kHz. The effects of single sweeping frequency and dual fixed frequency ultrasound were stronger than those of single fixed frequency ultrasound for improving the ACE inhibitory activity of zein. Structural changes in zein were induced by ultrasound, as confirmed by changes in the solubility, H0, UV-Vis spectra, intrinsic fluorescence spectra, and CD spectra of zein, and these were consistent with the corresponding ACE inhibitory activities of zein hydrolysates. Thus, ultrasound working mode and frequency have significant effects on the structure of zein and the ACE inhibitory activity of zein hydrolysates.

  17. Fast-ball sports experts depend on an inhibitory strategy to reprogram their movement timing.

    Science.gov (United States)

    Nakamoto, Hiroki; Ikudome, Sachi; Yotani, Kengo; Maruyama, Atsuo; Mori, Shiro

    2013-07-01

    The purpose of our study was to clarify whether an inhibitory strategy is used for reprogramming of movement timing by experts in fast-ball sports when they correct their movement timing due to unexpected environmental changes. We evaluated the influence of disruption of inhibitory function of the right inferior frontal gyrus (rIFG) on reprogramming of movement timing of experts and non-experts in fast-ball sports. The task was to manually press a button to coincide with the arrival of a moving target. The target moved at a constant velocity, and its velocity was suddenly either increased or decreased in some trials. The task was performed either with or without transcranial magnetic stimulation (TMS), which was delivered to the region of the rIFG. Under velocity change conditions without TMS, the experts showed significantly smaller timing errors and a higher rate of reprogramming of movement timing than the non-experts. Moreover, TMS application during the task significantly diminished the expert group's performance, but not the control group, particularly in the condition where the target velocity decreases. These results suggest that experts use an inhibitory strategy for reprogramming of movement timing. In addition, the rIFG inhibitory function contributes to the superior movement correction of experts in fast-ball sports.

  18. What Do We Really Know about Cognitive Inhibition? Task Demands and Inhibitory Effects across a Range of Memory and Behavioural Tasks.

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    Saima Noreen

    Full Text Available Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks.

  19. ALTERACIONES DEL CONTROL INHIBITORIO CONDUCTUAL EN NIÑOS DE 6 A 11 AÑOS CON TDAH FAMILIAR DE BARRANQUILLA - BEHAVIORAL CHANGES OF INHIBITORY CONTROL IN CHILDREN FROM 6 TO 11 YEARS OLD WITH FAMILY ADHD FROM BARRANQUILLA

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    DAVID PINEDA SALAZAR

    2010-06-01

    Full Text Available Inhibitory control is the cognitive process responsible for the intentional and voluntary control, it means, the suppression of immediate responses requiring motor interference or behavioral inhibition. In this research, the multidimensional scale of behavior BASC-Teachers was used as a tool, for the description of executive behavior in the dimensions of behavioral control, emotional control, attention control and problem solving skills. We selected 52 children from 6 to 11 years old with family Attention Deficit Disorder Hyperactivity-ADHD and a control group. The main finding indicates that the dimension of executive behavior “problem solving” statistically and clinically differentiated children affected and not affected by ADHD, yielding in particular a lower score on the affected children. These results from the BASC-Executive validate the hypothesis regarding the presence of an alteration in the inhibitory behavioral control underlying the symptoms of ADHD.ResumenEl control inhibitorio es el proceso encargado del control intencional-voluntario, es decir, de la supresión de respuestas inmediatas que requieran interferencia motora o inhibición conductual.En la presente investigación, se utilizó como instrumento la escala multidimensional de la conducta BASC-Maestros para la descripción de las conductas ejecutivas en las dimensiones: control de la conducta, control emocional, control de la atención y capacidad de resolución de problemas. Se seleccionaron 52 niños de 6 a 11 años con Trastorno por Déficit de Atención Hiperactividad-TDAH familiar y un grupo control. Como principal hallazgo, se indica que la dimensión de conducta ejecutiva “solución de problemas” diferenció estadísticay clínicamente a los niños afectados y no afectados de TDAH, arrojando en particular una puntuación más pobre en los niños afectados. Estos resultados del BASC- Ejecutivo validan la hipótesis relativa a la presencia de una alteración en

  20. The biochemical anatomy of cortical inhibitory synapses.

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    Elizabeth A Heller

    Full Text Available Classical electron microscopic studies of the mammalian brain revealed two major classes of synapses, distinguished by the presence of a large postsynaptic density (PSD exclusively at type 1, excitatory synapses. Biochemical studies of the PSD have established the paradigm of the synapse as a complex signal-processing machine that controls synaptic plasticity. We report here the results of a proteomic analysis of type 2, inhibitory synaptic complexes isolated by affinity purification from the cerebral cortex. We show that these synaptic complexes contain a variety of neurotransmitter receptors, neural cell-scaffolding and adhesion molecules, but that they are entirely lacking in cell signaling proteins. This fundamental distinction between the functions of type 1 and type 2 synapses in the nervous system has far reaching implications for models of synaptic plasticity, rapid adaptations in neural circuits, and homeostatic mechanisms controlling the balance of excitation and inhibition in the mature brain.

  1. Inhibitory effect of Xenorhabdus nematophila TB on plant pathogens Phytophthora capsici and Botrytis cinerea in vitro and in planta.

    Science.gov (United States)

    Fang, Xiangling; Zhang, Manrang; Tang, Qian; Wang, Yonghong; Zhang, Xing

    2014-03-06

    Entomopathogenic bacteria Xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. This study evaluated the inhibitory effect of X. nematophila TB culture on plant pathogens Botrytis cinerea and Phytophthora capsici. The cell-free filtrate of TB culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. The methanol-extracted bioactive compounds (methanol extract) of TB culture also had strong inhibitory effects on mycelial growth and spore germinations of both pathogens. The methanol extract (1000 μg/mL) and cell-free filtrate both showed strong therapeutic and protective effects (>70%) on grey mold both in detached tomato fruits and plants, and leaf scorch in pepper plants. This study demonstrates X. nematophila TB produces antimicrobial metabolites of strong activity on plant pathogens, with great potential for controlling tomato grey mold and pepper leaf scorch and being used in integrated disease control to reduce chemical application.

  2. Inhibitory effects of Cheongsangbangpoong-tang on both inflammatory acne lesions and facial heat in patients with acne vulgaris: A randomized controlled trial protocol.

    Science.gov (United States)

    Kim, Kyuseok; Kim, Kwan-Il; Lee, Junhee

    2016-01-22

    Due to increasing interest from acne patients concerned about the side effects associated with conventional therapies, complementary and alternative medicine (CAM) has been suggested as a new therapeutic modality for acne vulgaris. Herbal medicine is one of these CAM treatments. Cheongsangbangpoong-tang (CBT) is a common herbal formula used in patients with acne vulgaris in the clinical practice of Korean Medicine (KM). However, despite the common use of CBT in clinical practice, the current level of evidence is insufficient to support an inhibitory effect of CBT on inflammatory acne lesions and facial heat. Therefore, this study was designed to assess the inhibitory effect of CBT on both inflammatory acne lesions and facial heat. A randomized, double-blind, parallel-group, and placebo-controlled trial will be conducted. Fifty-six participants with acne vulgaris will be randomized into one of two groups: the CBT or placebo groups. After randomization, participants will be prescribed either CBT or placebo three times a day at a dose of 5 g after meals for 8 weeks. The following outcome measurements will be used in the examination of subjects: the mean percentage change and the count change of the inflammatory and non-inflammatory acne lesions, the temperature of facial points on digital infrared thermal imaging (DITI), serum cortisol, serum dehydroepiandrosterone-sulfate (DHEA-S), visual analogue scale (VAS), investigator global assessment (IGA), and severity score on the Korean Acne Grading System (KAGS) from baseline to the end of the trial. This trial will provide evidence regarding the inhibitory effect of CBT on inflammatory acne lesions and facial heat. The findings of this trial may have important implications for the more widespread use of CBT for the treatment of acne vulgaris. The trial is registered with the Clinical Research Information Service (CRiS), Republic of Korea: KCT0001468 .

  3. Altered BOLD response during inhibitory and error processing in adolescents with anorexia nervosa.

    Directory of Open Access Journals (Sweden)

    Christina Wierenga

    Full Text Available BACKGROUND: Individuals with anorexia nervosa (AN are often cognitively rigid and behaviorally over-controlled. We previously showed that adult females recovered from AN relative to healthy comparison females had less prefrontal activation during an inhibition task, which suggested a functional brain correlate of altered inhibitory processing in individuals recovered from AN. However, the degree to which these functional brain alterations are related to disease state and whether error processing is altered in AN individuals is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the current study, ill adolescent AN females (n = 11 and matched healthy comparison adolescents (CA with no history of an eating disorder (n = 12 performed a validated stop signal task (SST during functional magnetic resonance imaging (fMRI to explore differences in error and inhibitory processing. The groups did not differ on sociodemographic variables or on SST performance. During inhibitory processing, a significant group x difficulty (hard, easy interaction was detected in the right dorsal anterior cingulate cortex (ACC, right middle frontal gyrus (MFG, and left posterior cingulate cortex (PCC, which was characterized by less activation in AN compared to CA participants during hard trials. During error processing, a significant group x accuracy (successful inhibit, failed inhibit interaction in bilateral MFG and right PCC was observed, which was characterized by less activation in AN compared to CA participants during error (i.e., failed inhibit trials. CONCLUSION/SIGNIFICANCE: Consistent with our prior findings in recovered AN, ill AN adolescents, relative to CA, showed less inhibition-related activation within the dorsal ACC, MFG and PCC as inhibitory demand increased. In addition, ill AN adolescents, relative to CA, also showed reduced activation to errors in the bilateral MFG and left PCC. These findings suggest that altered prefrontal and cingulate activation during

  4. Age Effect on Automatic Inhibitory Function of the Somatosensory and Motor Cortex: An MEG Study

    Directory of Open Access Journals (Sweden)

    Chia-Hsiung Cheng

    2018-03-01

    Full Text Available Age-related deficiency in the top-down modulation of cognitive inhibition has been extensively documented, whereas the effects of age on a bottom-up or automatic operation of inhibitory function were less investigated. It is unknown that whether the older adults (OA’ reduced behavioral performance and neural responses are due to the insufficient bottom-up processes. Compared to behavioral assessments which have been widely used to examine the top-down control of response inhibition, electrophysiological recordings are more suitable to probe the early-stage processes of automatic inhibitory function. Sensory gating (SG, a phenomenon of attenuated neural response to the second identical stimulus in a paired-pulse paradigm, is an indicator to assess automatic inhibitory function of the sensory cortex. On the other hand, electricity-induced beta rebound oscillation in a single-pulse paradigm reflects cortical inhibition of the motor cortex. From the neurophysiological perspective, SG and beta rebound oscillation are replicable indicators to examine the automatic inhibitory function of human sensorimotor cortices. Thus, the present study aimed to use a whole-head magnetoencephalography (MEG to investigate the age-related alterations of SG function in the primary somatosensory cortex (SI and of beta rebound oscillation in the primary motor cortex (MI in 17 healthy younger and 15 older adults. The Stimulus 2/Stimulus 1 (S2/S1 amplitude ratio in response to the paired-pulse electrical stimulation to the left median nerve was used to evaluate the automatic inhibitory function of SI, and the beta rebound response in the single-pulse paradigm was used to evaluate the automatic inhibitory function of MI. Although there were no significant age-related differences found in the SI SG ratios, the MI beta rebound power was reduced and peak latency was prolonged in the OA. Furthermore, significant association between the SI SG ratio and the MI beta rebound

  5. Age Effect on Automatic Inhibitory Function of the Somatosensory and Motor Cortex: An MEG Study

    Science.gov (United States)

    Cheng, Chia-Hsiung; Lin, Mei-Yin; Yang, Shiou-Han

    2018-01-01

    Age-related deficiency in the top-down modulation of cognitive inhibition has been extensively documented, whereas the effects of age on a bottom-up or automatic operation of inhibitory function were less investigated. It is unknown that whether the older adults (OA)’ reduced behavioral performance and neural responses are due to the insufficient bottom-up processes. Compared to behavioral assessments which have been widely used to examine the top-down control of response inhibition, electrophysiological recordings are more suitable to probe the early-stage processes of automatic inhibitory function. Sensory gating (SG), a phenomenon of attenuated neural response to the second identical stimulus in a paired-pulse paradigm, is an indicator to assess automatic inhibitory function of the sensory cortex. On the other hand, electricity-induced beta rebound oscillation in a single-pulse paradigm reflects cortical inhibition of the motor cortex. From the neurophysiological perspective, SG and beta rebound oscillation are replicable indicators to examine the automatic inhibitory function of human sensorimotor cortices. Thus, the present study aimed to use a whole-head magnetoencephalography (MEG) to investigate the age-related alterations of SG function in the primary somatosensory cortex (SI) and of beta rebound oscillation in the primary motor cortex (MI) in 17 healthy younger and 15 older adults. The Stimulus 2/Stimulus 1 (S2/S1) amplitude ratio in response to the paired-pulse electrical stimulation to the left median nerve was used to evaluate the automatic inhibitory function of SI, and the beta rebound response in the single-pulse paradigm was used to evaluate the automatic inhibitory function of MI. Although there were no significant age-related differences found in the SI SG ratios, the MI beta rebound power was reduced and peak latency was prolonged in the OA. Furthermore, significant association between the SI SG ratio and the MI beta rebound power, which was

  6. Myostatin inhibitory region of fish (Paralichthys olivaceus) myostatin-1 propeptide.

    Science.gov (United States)

    Lee, Sang Beum; Kim, Jeong Hwan; Jin, Deuk-Hee; Jin, Hyung-Joo; Kim, Yong Soo

    2016-01-01

    Myostatin (MSTN) is a potent negative regulator of skeletal muscle growth, and its activity is suppressed by MSTN propeptide (MSTNpro), the N-terminal part of MSTN precursor cleaved during post-translational MSTN processing. The current study examined which region of flatfish (Paralichthys olivaceus) MSTN-1 propeptide (MSTN1pro) is critical for MSTN inhibition. Six different truncated forms of MSTN1pro containing N-terminal maltose binding protein (MBP) as a fusion partner were expressed in Escherichia coli, and partially purified by an affinity chromatography for MSTN-inhibitory activity examination. Peptides covering different regions of flatfish MSTN1pro were also synthesized for MSTN-inhibitory activity examination. A MBP-fused MSTN1pro region consisting of residues 45-100 had the same MSTN-inhibitory potency as the full sequence flatfish MSTN1pro (residues 23-265), indicating that the region of flatfish MSTN1pro consisting of residues 45-100 is sufficient to maintain the full MSTN-inhibitory capacity. A MBP-fused MSTN1pro region consisting of residues 45-80 (Pro45-80) also showed MSTN-inhibitory activity with a lower potency, and the Pro45-80 demonstrated its MSTN binding capacity in a pull-down assay, indicating that the MSTN-inhibitory capacity of Pro45-80 is due to its binding to MSTN. Flatfish MSTN1pro synthetic peptides covering residues 45-65, 45-70, and 45-80 demonstrated MSTN-inhibitory activities, but not the synthetic peptide covering residues 45-54, indicating that residues 45-65 of flatfish MSTN1pro are essential for MSTN inhibition. In conclusion, current study show that like the mammalian MSTNpro, the MSTN-inhibitory region of flatfish MSTN1pro resides near its N-terminus, and imply that smaller sizes of MSTNpro can be effectively used in various applications designed for MSTN inhibition. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Evaluation of the tannic acid inhibitory effect against the NorA efflux pump of Staphylococcus aureus.

    Science.gov (United States)

    Tintino, Saulo R; Oliveira-Tintino, Cícera D M; Campina, Fábia F; Silva, Raimundo L P; Costa, Maria do S; Menezes, Irwin R A; Calixto-Júnior, João T; Siqueira-Junior, José P; Coutinho, Henrique D M; Leal-Balbino, Tereza C; Balbino, Valdir Q

    2016-08-01

    During the early periods of antibiotic usage, bacterial infections were considered tamed. However, widespread antibiotic use has promoted the emergence of antibiotic-resistant pathogens, including multidrug resistant strains. Active efflux is a mechanism for bacterial resistance to inhibitory substances, known simply as drug efflux pumps. The bacterium Staphylococcus aureus is an important pathogenic bacterium responsible for an array of infections. The NorA efflux pump has been shown to be responsible for moderate fluoroquinolone resistance of S. aureus. The inhibition of the efflux pump was assayed using a sub-inhibitory concentration of standard efflux pump inhibitors and tannic acid (MIC/8), where its capacity to decrease the MIC of Ethidium bromide (EtBr) and antibiotics due to the possible inhibitory effect of these substances was observed. The MICs of EtBr and antibiotics were significantly reduced in the presence of tannic acid, indicating the inhibitory effect of this agent against the efflux pumps of both strains causing a three-fold reduction of the MIC when compared with the control. These results indicate the possible usage of tannic acid as an adjuvant in antibiotic therapy against multidrug resistant bacteria (MDR). Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. A deleterious Nav1.1 mutation selectively impairs telencephalic inhibitory neurons derived from Dravet Syndrome patients

    Science.gov (United States)

    Sun, Yishan; Paşca, Sergiu P; Portmann, Thomas; Goold, Carleton; Worringer, Kathleen A; Guan, Wendy; Chan, Karen C; Gai, Hui; Vogt, Daniel; Chen, Ying-Jiun J; Mao, Rong; Chan, Karrie; Rubenstein, John LR; Madison, Daniel V; Hallmayer, Joachim; Froehlich-Santino, Wendy M; Bernstein, Jonathan A; Dolmetsch, Ricardo E

    2016-01-01

    Dravet Syndrome is an intractable form of childhood epilepsy associated with deleterious mutations in SCN1A, the gene encoding neuronal sodium channel Nav1.1. Earlier studies using human induced pluripotent stem cells (iPSCs) have produced mixed results regarding the importance of Nav1.1 in human inhibitory versus excitatory neurons. We studied a Nav1.1 mutation (p.S1328P) identified in a pair of twins with Dravet Syndrome and generated iPSC-derived neurons from these patients. Characterization of the mutant channel revealed a decrease in current amplitude and hypersensitivity to steady-state inactivation. We then differentiated Dravet-Syndrome and control iPSCs into telencephalic excitatory neurons or medial ganglionic eminence (MGE)-like inhibitory neurons. Dravet inhibitory neurons showed deficits in sodium currents and action potential firing, which were rescued by a Nav1.1 transgene, whereas Dravet excitatory neurons were normal. Our study identifies biophysical impairments underlying a deleterious Nav1.1 mutation and supports the hypothesis that Dravet Syndrome arises from defective inhibitory neurons. DOI: http://dx.doi.org/10.7554/eLife.13073.001 PMID:27458797

  9. Angiotensin I-Converting Enzyme (ACE Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    Directory of Open Access Journals (Sweden)

    Małgorzata Darewicz

    2014-08-01

    Full Text Available The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes and ex vivo digestion (with human gastrointestinal enzymes. Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50% of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  10. Nootropic dipeptide noopept enhances inhibitory synaptic transmission in the hippocampus.

    Science.gov (United States)

    Povarov, I S; Kondratenko, R V; Derevyagin, V I; Ostrovskaya, R U; Skrebitskii, V G

    2015-01-01

    Application of nootropic agent Noopept on hippocampal slices from Wistar rats enhanced the inhibitory component of total current induced by stimulation of Shaffer collaterals in CA1 pyramidal neurons, but did not affect the excitatory component. A direct correlation between the increase in the amplitude of inhibitory current and agent concentration was found. The substance did not affect the release of inhibitory transmitters from terminals in the pyramidal neurons, which indicated changes in GABAergic interneurons.

  11. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

    Directory of Open Access Journals (Sweden)

    Zhiqing Zhang

    2016-11-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection causes acquired immune deficiency syndrome (AIDS, a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  12. The impact of fermentation and in vitro digestion on formation angiotensin converting enzyme (ACE) inhibitory peptides from pea proteins.

    Science.gov (United States)

    Jakubczyk, Anna; Karaś, Monika; Baraniak, Barbara; Pietrzak, Marlena

    2013-12-15

    Pea seeds were fermented by Lactobacillus plantarum 299v in monoculture under different time and temperature conditions and the fermented products were digested in vitro under gastrointestinal conditions. After fermentation and digestion ACE inhibitory activity was determined. In all samples after fermentation no ACE inhibitory activity was noted. Potentially antihypertensive peptides were released during in vitro digestion. The highest DH (68.62%) were noted for control sample, although the lowest IC50 value (0.19 mg/ml) was determined for product after 7 days fermentation at 22 °C. The hydrolysate characterised by the highest ACE inhibitory activity was separated on Sephadex G10 and two peptides fractions were obtained. The highest ACE inhibitory activity (IC50=64.04 μg/ml) for the first fraction was noted. This fraction was separated by HPLC and identified by LC-MS/MS and the sequence of peptide derived from pea proteins was determined as KEDDEEEEQGEEE. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Population activity structure of excitatory and inhibitory neurons.

    Science.gov (United States)

    Bittner, Sean R; Williamson, Ryan C; Snyder, Adam C; Litwin-Kumar, Ashok; Doiron, Brent; Chase, Steven M; Smith, Matthew A; Yu, Byron M

    2017-01-01

    Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure.

  14. Population activity structure of excitatory and inhibitory neurons.

    Directory of Open Access Journals (Sweden)

    Sean R Bittner

    Full Text Available Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure.

  15. Population activity structure of excitatory and inhibitory neurons

    Science.gov (United States)

    Doiron, Brent

    2017-01-01

    Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure. PMID:28817581

  16. Cognitive-electrophysiological indices of attentional and inhibitory processing in adults with ADHD: familial effects

    Directory of Open Access Journals (Sweden)

    McLoughlin Gráinne

    2011-07-01

    Full Text Available Abstract Background Attention deficit hyperactivity disorder (ADHD is a common neurodevelopmental disorder that starts in childhood and frequently persists in adults. In a comparison of adults with ADHD and a matched control sample, we previously showed that abnormal inhibitory processing is typically preceded or accompanied by other processing deficits in adult ADHD. We now compare these data further to additional data from first-degree relatives (fathers of children with ADHD to identify whether this pattern of abnormal processing shares familial influences with ADHD in adults. Methods Using a family design, we compared 20 fathers of children with the combined subtype of ADHD with 21 adults with ADHD combined subtype and 20 controls in event-related potential indices of preparatory states and subsequent response inhibition processing as elicited by a cued continuous performance task. Results Fathers of children with ADHD exhibited significantly weaker orienting attention to cues and inhibitory processing than the controls but not the ADHD sample. Conclusions These findings provide evidence for the familial association of attentional orienting and response inhibition processes with ADHD in adults and indicate a familial and neurobiological link between ADHD in children and adults.

  17. Regulation and control of nitric oxide (NO) in macrophages

    DEFF Research Database (Denmark)

    Kovacevic, Zaklina; Sahni, Sumit; Lok, K.H.

    2017-01-01

    We recently demonstrated that a novel storage and transport mechanism for nitric oxide (NO) mediated by glutathione-S-transferase P1 (GSTP1) and multidrug resistance protein 1 (MRP1/ABCC1), protects M1-macrophage (M1-MØ) models from large quantities of endogenous NO. This system stores and transp......We recently demonstrated that a novel storage and transport mechanism for nitric oxide (NO) mediated by glutathione-S-transferase P1 (GSTP1) and multidrug resistance protein 1 (MRP1/ABCC1), protects M1-macrophage (M1-MØ) models from large quantities of endogenous NO. This system stores...... be responsible for delivering cytotoxic NO as DNICs via MRP1 from M1-MØs, to tumor cell targets....

  18. Antioxidant, Iron Chelating and Tyrosinase Inhibitory Activities of Extracts from Talinum triangulare Leach Stem

    Directory of Open Access Journals (Sweden)

    Ana Paula Oliveira Amorim

    2013-07-01

    Full Text Available The aim of this work is to evaluate the antioxidant activity against the radical species DPPH, the reducing capacity against Fe II ions, and the inhibitory activity on the tyrosinase enzyme of the T. triangulare. Hydromethanolic crude extract provided two fractions after the liquid/liquid partition with chloroform. The Folin-Ciocalteu method determined the total phenolic content of the crude extract (CE and the hydromethanolic fraction (Fraction 1, resulting in a concentration of 0.5853 g/100 g for Fraction 1, and 0.1400 g/100 g for the CE. Taking into account the results of the DPPH, the free radical scavenging capacity was confirmed. The formation of complexes with Fe II ions was evaluated by UV/visible spectrometry; results showed that CE has complexing power similar to the positive control (Gingko biloba extract.The inhibitory capacity of samples against the tyrosinase enzyme was determined by the oxidation of L-DOPA, providing IC50 values of 13.3 μg·mL−1 (CE and 6.6 μg·mL−1 (Fraction 1. The values indicate that Fraction 1 was more active and showed a higher inhibitory power on the tyrosinase enzyme than the ascorbic acid, used as positive control. The hydromethanolic extract of T. triangulare proved to have powerful antioxidant activity and to inhibit the tyrosinase enzyme; its potential is increased after the partition with chloroform.

  19. [Inhibitory effect of diclofenac sodium on the proliferation of rabbit corneal epithelial cells in vitro].

    Science.gov (United States)

    Wu, Ningling; Du, Zhiyu

    2010-11-01

    To investigate the inhibitory effect of diclofenac sodium on rabbit corneal epithelial cells (RCECs) in vitro and explore its pharmacological mechanism. The fresh rabbit cornea was cultured to obtain the primary RCECs, and RCECs of passage 2 were used in this research. The cells were divided into experimental groups, the cells in which were incubated with different concentrations (18.18, 27.27, 36.36, 45.45, 54.55 μg/ml) of diclofenac sodium, and control group. The effect of diclofenac sodium on the proliferation of cells was measured by methyl thiazolyl thiazolium (MTT) assay 24, 48 and 72 h after incubation. While the RCECs were divided into experimental groups, the cells in which were incubated with 9 and 12.5 μg/ml diclofenac sodium, and control group. The cell cycle and apoptotic rate were observed by flow cytometer. MTT assay showed that diclofenac sodium had obvious inhibitory effect on RCECs, and the inhibition rate was increasing along with the increasing concentration of diclofenac sodium and the incubation time(Pdiclofenac sodium, the cells in G0/G1 phase were obviously increased, and the apoptosis cusp and apoptotic rate were increased. Diclofenac sodium exerts significant inhibitory effect on RCECs in a dosage-dependent manner, and it may function by inducing cell apoptosis and ceasing cell cycles.

  20. Intrinsically-generated fluctuating activity in excitatory-inhibitory networks

    Science.gov (United States)

    Mastrogiuseppe, Francesca; Ostojic, Srdjan

    2017-01-01

    Recurrent networks of non-linear units display a variety of dynamical regimes depending on the structure of their synaptic connectivity. A particularly remarkable phenomenon is the appearance of strongly fluctuating, chaotic activity in networks of deterministic, but randomly connected rate units. How this type of intrinsically generated fluctuations appears in more realistic networks of spiking neurons has been a long standing question. To ease the comparison between rate and spiking networks, recent works investigated the dynamical regimes of randomly-connected rate networks with segregated excitatory and inhibitory populations, and firing rates constrained to be positive. These works derived general dynamical mean field (DMF) equations describing the fluctuating dynamics, but solved these equations only in the case of purely inhibitory networks. Using a simplified excitatory-inhibitory architecture in which DMF equations are more easily tractable, here we show that the presence of excitation qualitatively modifies the fluctuating activity compared to purely inhibitory networks. In presence of excitation, intrinsically generated fluctuations induce a strong increase in mean firing rates, a phenomenon that is much weaker in purely inhibitory networks. Excitation moreover induces two different fluctuating regimes: for moderate overall coupling, recurrent inhibition is sufficient to stabilize fluctuations; for strong coupling, firing rates are stabilized solely by the upper bound imposed on activity, even if inhibition is stronger than excitation. These results extend to more general network architectures, and to rate networks receiving noisy inputs mimicking spiking activity. Finally, we show that signatures of the second dynamical regime appear in networks of integrate-and-fire neurons. PMID:28437436

  1. A combined electrophysiological and morphological study of neuropeptide Y?expressing inhibitory interneurons in the spinal dorsal horn of the mouse

    OpenAIRE

    Iwagaki, Noboru; Ganley, Robert P.; Dickie, Allen C.; Polg?r, Erika; Hughes, David I.; Del Rio, Patricia; Revina, Yulia; Watanabe, Masahiko; Todd, Andrew J.; Riddell, John S.

    2015-01-01

    Abstract The spinal dorsal horn contains numerous inhibitory interneurons that control transmission of somatosensory information. Although these cells have important roles in modulating pain, we still have limited information about how they are incorporated into neuronal circuits, and this is partly due to difficulty in assigning them to functional populations. Around 15% of inhibitory interneurons in laminae I-III express neuropeptide Y (NPY), but little is known about this population. We th...

  2. TGF-β Signaling in Dopaminergic Neurons Regulates Dendritic Growth, Excitatory-Inhibitory Synaptic Balance, and Reversal Learning

    Directory of Open Access Journals (Sweden)

    Sarah X. Luo

    2016-12-01

    Full Text Available Neural circuits involving midbrain dopaminergic (DA neurons regulate reward and goal-directed behaviors. Although local GABAergic input is known to modulate DA circuits, the mechanism that controls excitatory/inhibitory synaptic balance in DA neurons remains unclear. Here, we show that DA neurons use autocrine transforming growth factor β (TGF-β signaling to promote the growth of axons and dendrites. Surprisingly, removing TGF-β type II receptor in DA neurons also disrupts the balance in TGF-β1 expression in DA neurons and neighboring GABAergic neurons, which increases inhibitory input, reduces excitatory synaptic input, and alters phasic firing patterns in DA neurons. Mice lacking TGF-β signaling in DA neurons are hyperactive and exhibit inflexibility in relinquishing learned behaviors and re-establishing new stimulus-reward associations. These results support a role for TGF-β in regulating the delicate balance of excitatory/inhibitory synaptic input in local microcircuits involving DA and GABAergic neurons and its potential contributions to neuropsychiatric disorders.

  3. Enzyme inhibitory activity of selected Philippine plants

    International Nuclear Information System (INIS)

    Sasotona, Joseph S.; Hernandez, Christine C.

    2015-01-01

    In the Philippines, the number one cause of death are cardiovascular diseases. Diseases linked with inflammation are proliferating. This research aims to identify plant extracts that have potential activity of cholesterol-lowering, anti-hypertension, anti-gout, anti-inflammatory and fat blocker agents. Although there are commercially available drugs to treat the aforementioned illnesses, these medicine have adverse side-effects, aside from the fact that they are expensive. The results of this study will serve as added knowledge to contribute to the development of cheaper, more readily available, and effective alternative medicine. 100 plant extracts from different areas in the Philippines have been tested for potential inhibitory activity against Hydroxymethylglutaryl-coenzyme A (HMG-CoA), Lipoxygenase, and Xanthine Oxidase. The plant samples were labeled with codes and distributed to laboratories for blind testing. The effective concentration of the samples tested for Xanthine oxidase is 100 ppm. Samples number 9, 11, 14, 29, 43, 46, and 50 have shown significant inhibitory activity at 78.7%, 78.4%, 70%, 89.2%, 79%, 67.4%, and 67.5% respectively. Samples tested for Lipoxygenase inhibition were set at 33ppm. Samples number 2, 37, 901, 1202, and 1204 have shown significant inhibitory activity at 66, 84.9%, 88.55%, 93.3%, and 84.7% respectively. For HMG-CoA inhibition, the effective concentration of the samples used was 100 ppm. Samples number 1 and 10 showed significant inhibitory activity at 90.1% and 81.8% respectively. (author)

  4. The influence of emotions on cognitive control: Feelings and beliefs – where do they meet?

    Directory of Open Access Journals (Sweden)

    Katia M Harlé

    2013-09-01

    Full Text Available The influence of emotion on higher-order cognitive functions, such as attention allocation, planning, and decision-making, is a growing area of research with important clinical applications. In this review, we provide a computational framework to conceptualize emotional influences on inhibitory control, an important building block of executive functioning. We first summarize current neurocognitive models of inhibitory control and show how Bayesian ideal observer models can help reframe inhibitory control as a dynamic decision-making process. Finally, we propose a Bayesian framework to study emotional influences on inhibitory control, providing several hypotheses that may be useful to conceptualize inhibitory control biases in mental illness such as depression and anxiety. To do so, we consider the neurocognitive literature pertaining to how affective states can bias inhibitory control, with particular attention to how valence and arousal may independently impact inhibitory control by biasing probabilistic representations of information (i.e., beliefs and valuation processes (e.g., speed-error tradeoffs.

  5. Free Radical Scavenging and Alpha/Beta-glucosidases Inhibitory Activities of Rambutan (Nephelium lappaceum L. Peel Extract

    Directory of Open Access Journals (Sweden)

    Wahyu Widowati

    2015-12-01

    Full Text Available BACKGROUND: Diabetes mellitus (DM is associated with oxidative reaction and hyperglycemic condition. Human body has an antioxidant defense system toward free radical, but overproduction of free radical causing imbalance condition between the free radical and the antioxidant defense in the body that lead to several diseases, including DM. Glucosidase is an enzyme that hydrolize carbohydrates causing increase of blood glucose level, so by inhibiting this enzyme blood glucose level in plasma could be effectively decreased. Rambutan (Nephelium lappaceum L. peel has been reported to have many potential roles, such as antioxidant and anti-glycemia. Therefore our current study was conducted to evaluate possible effectivity of Rambutan peel to scavenge free radical and to inhibit α- and β-glucosidases. METHODS: Rambutan peel extraction (RPE was performed based on maceration method. Geraniin was used as control. For antioxidant study, 2,2-diphenyl-1- picrylhydrazyl (DPPH free radical scavenging test was performed. For glucosidase inhibitory activity study,  α- and β-glucosidases inhibitory activity tests were performed. Results were analyzed for median of Inhibitory Concentration (IC50. RESULTS: The scavenging activity of RPE was comparable with Geraniin. Meanwhile, the α-glucosidase inhibitory activity of RPE was higher than the one of Geraniin. The α-glucosidase-inhibitory-activity IC50 of RPE and Geraniin were 0.106±0.080 μg/ml and 16.12±0.29 μg/ml, respectively. The β-glucosidase inhibitory activity of RPE was also higher than the one of Geraniin. The β-glucosidase-inhibitory-activity IC50 of RPE and Geraniin were 7.02±0.99 μg/ml and 19.81±0.66 μg/ml, respectively. CONCLUSIONS: Since RPE showed comparable free radical scavenging activity with Geraniin and higher α- and β-glucosidases inhibitory activities than Geraniin, RPE could be suggested as a promising antioxidant and antiglycemic agent.  KEYWORDS

  6. [Detection of nitrite and nitrosocompounds in chemical systems and biological liquids by the calorimetric method].

    Science.gov (United States)

    Titov, V Iu; Petrenko, Iu M; Vanin, A F; Stepuro, I I

    2010-01-01

    The capacity of nitrite, S-nitrosothiols (RS-NO), dinitrosyl iron complexes (DNICs) with thiol-containing ligands, and nitrosoamines to inhibit catalase has been used for the selective determination of these compounds in purely chemical systems and biological liquids: cow milk and colostram. The limiting sensitivity of the method is 50 nM. A comparison of the results of the determinations of RS-NO, DNIC, and nitrite by the catalase method and the Greese method conventionally used for nitrite detection showed that, firstly, Greese reagents decompose DNIC and RS-NO to form nitrite. Therefore, the Greese method cannot be used for nitrite determination in solutions of these substances. Secondly, Greese reagents interact with complexes of mercury ions with RS-NO, inducing the release of nitrosonium ions from the complex followed by the hydrolysis of nitrosonium to nitrite. Thus, the proposition about the spontaneous decay of the complexes of mercury ions with RS-NO is incorrect. Keeping in mind a high sensitivity of the method, the use of catalase as an enzyme detector of nitrosocompounds allows one to detect these compounds in neutral medium without prior purification of the object, thereby preventing artificial effects due to noncontrolled modifications of the compounds under study.

  7. Fission-fusion dynamics, behavioral flexibility, and inhibitory control in primates.

    Science.gov (United States)

    Amici, Federica; Aureli, Filippo; Call, Josep

    2008-09-23

    The Machiavellian Intelligence or Social Brain Hypothesis explains the evolution of increased brain size as mainly driven by living in complex organized social systems in which individuals represent "moving targets" who can adopt multiple strategies to respond to one another. Frequently splitting and merging in subgroups of variable composition (fission-fusion or FF dynamics) has been proposed as one aspect of social complexity ( compare with) that may be associated with an enhancement of cognitive skills like inhibition, which allows the suppression of prepotent but ineffective responses in a changing social environment. We compared the performance of primates experiencing high levels of FF dynamics (chimpanzees, bonobos, orangutans, and spider monkeys) to that of species living in more cohesive groups (gorillas, capuchin monkeys, and long-tailed macaques) on five inhibition tasks. Testing species differing in diet, phylogenetic relatedness, and levels of FF dynamics allowed us to contrast ecological, phylogenetic, and socioecological explanations for interspecific differences. Spider monkeys performed at levels comparable to chimpanzees, bonobos, and orangutans, and better than gorillas. A two-cluster analysis grouped all species with higher levels of FF dynamics together. These findings confirmed that enhanced inhibitory skills are positively associated with FF dynamics, more than to phylogenetic relations or feeding ecology.

  8. Effect of Hyperglycemia on Purinergic and Nitrergic Inhibitory Neuromuscular Transmission in the Antrum of the Stomach: Implications for Fast Gastric Emptying

    Directory of Open Access Journals (Sweden)

    Xue-Dao He

    2018-01-01

    Full Text Available BackgroundHyperglycemia has been reported to enhance vagovagal reflex that causes the release of inhibitory neurotransmitter, nitric oxide (NO, at the neuromuscular junction in the antrum to relax the antrum and slow gastric emptying by stimulating glucose-sensitive afferent neurons. However, hyperglycemia has also been reported to cause fast gastric emptying that may be due to suppression of the inhibitory motor neurons.AimsThe purpose of the present study was to investigate changes in inhibitory neuromuscular transmission in the gastric antrum due to hyperglycemia.MethodsInhibitory electrical junction potentials were recorded from gastric antral muscle strips, using intracellular electrodes under non-adrenergic, non-cholinergic conditions. Studies were performed in non-hyperglycemic NOD (NH-NOD, NOD mice as they develop hyperglycemia (H-NOD and their age-matched controls. The purinergic inhibitory junction potential (pIJP and nitrergic IJP (nIJP were isolated pharmacologically.ResultsThe control pIJP was large, around −18 mV and nIJP was small, around −9 mV. In NH-NOD the IJPs were not affected, but in H-NOD pIJP was nearly abolished and nIJP was significantly reduced. In H-NOD mice, membrane hyperpolarization caused by exogenous α,β-MeATP or diethylenetriamine NO adduct was similar to that in wild-type controls (P > 0.05. H-NOD smooth muscles were significantly depolarized as compared to NH-NOD smooth muscles.ConclusionThese observations show that hyperglycemia causes suppression of purinergic and nitrergic transmission by acting on the motor neurons that form the last neuron in the vagovagal circuit. Moreover, the loss the neurotransmission is due to a defect in neurotransmitter release rather than a defect in signal transduction. Hyperglycemia also causes depolarization of smooth muscles that may increase their excitability.

  9. Inhibitory phenotype of HBV-specific CD4+ T-cells is characterized by high PD-1 expression but absent coregulation of multiple inhibitory molecules.

    Directory of Open Access Journals (Sweden)

    Bijan Raziorrouh

    Full Text Available T-cell exhaustion seems to play a critical role in CD8+ T-cell dysfunction during chronic viral infections. However, up to now little is known about the mechanisms underlying CD4+ T-cell dysfunction during chronic hepatitis B virus (CHB infection and the role of inhibitory molecules such as programmed death 1 (PD-1 for CD4+ T-cell failure.The expression of multiple inhibitory molecules such as PD-1, CTLA-4, TIM-3, CD244, KLRG1 and markers defining the grade of T-cell differentiation as CCR7, CD45RA, CD57 and CD127 were analyzed on virus-specific CD4+ T-cells from peripheral blood using a newly established DRB1*01-restricted MHC class II Tetramer. Effects of in vitro PD-L1/2 blockade were defined by investigating changes in CD4+ T-cell proliferation and cytokine production.CD4+ T-cell responses during chronic HBV infection was characterized by reduced Tetramer+CD4+ T-cell frequencies, effector memory phenotype, sustained PD-1 but low levels of CTLA-4, TIM-3, KLRG1 and CD244 expression. PD-1 blockade revealed individualized patterns of in vitro responsiveness with partly increased IFN-γ, IL-2 and TNF-α secretion as well as enhanced CD4+ T-cell expansion almost in treated patients with viral control.HBV-specific CD4+ T-cells are reliably detectable during different courses of HBV infection by MHC class II Tetramer technology. CD4+ T-cell dysfunction during chronic HBV is basically linked to strong PD-1 upregulation but absent coregulation of multiple inhibitory receptors. PD-L1/2 neutralization partly leads to enhanced CD4+ T-cell functionality with heterogeneous patterns of CD4+ T-cell rejunivation.

  10. Training Attentional Control Improves Cognitive and Motor Task Performance.

    Science.gov (United States)

    Ducrocq, Emmanuel; Wilson, Mark; Vine, Sam; Derakshan, Nazanin

    2016-10-01

    Attentional control is a necessary function for the regulation of goal-directed behavior. In three experiments we investigated whether training inhibitory control using a visual search task could improve task-specific measures of attentional control and performance. In Experiment 1 results revealed that training elicited a near-transfer effect, improving performance on a cognitive (antisaccade) task assessing inhibitory control. In Experiment 2 an initial far-transfer effect of training was observed on an index of attentional control validated for tennis. The principal aim of Experiment 3 was to expand on these findings by assessing objective gaze measures of inhibitory control during the performance of a tennis task. Training improved inhibitory control and performance when pressure was elevated, confirming the mechanisms by which cognitive anxiety impacts performance. These results suggest that attentional control training can improve inhibition and reduce taskspecific distractibility with promise of transfer to more efficient sporting performance in competitive contexts.

  11. Angiotensin-converting enzyme-inhibitory activity in protein hydrolysates from normal and anthracnose disease-damaged Phaseolus vulgaris seeds.

    Science.gov (United States)

    Hernández-Álvarez, Alan Javier; Carrasco-Castilla, Janet; Dávila-Ortiz, Gloria; Alaiz, Manuel; Girón-Calle, Julio; Vioque-Peña, Javier; Jacinto-Hernández, Carmen; Jiménez-Martínez, Cristian

    2013-03-15

    Bean seeds are an inexpensive source of protein. Anthracnose disease caused by the fungus Colletotrichum lindemuthianum results in serious losses in common bean (Phaseolus vulgaris L.) crops worldwide, affecting any above-ground plant part, and protein dysfunction, inducing the synthesis of proteins that allow plants to improve their stress tolerance. The aim of this study was to evaluate the use of beans damaged by anthracnose disease as a source of peptides with angiotensin-converting enzyme (ACE-I)-inhibitory activity. Protein concentrates from beans spoiled by anthracnose disease and from regular beans as controls were prepared by alkaline extraction and precipitation at isolelectric pH and hydrolysed using Alcalase 2.4 L. The hydrolysates from spoiled beans had ACE-I-inhibitory activity (IC(50) 0.0191 mg protein mL(-1)) and were very similar to those from control beans in terms of ACE-I inhibition, peptide electrophoretic profile and kinetics of hydrolysis. Thus preparation of hydrolysates using beans affected by anthracnose disease would allow for revalorisation of this otherwise wasted product. The present results suggest the use of spoiled bean seeds, e.g. anthracnose-damaged beans, as an alternative for the isolation of ACE-I-inhibitory peptides to be further introduced as active ingredients in functional foods. © 2012 Society of Chemical Industry.

  12. Comparative phytochemical and growth inhibitory studies on the leaf ...

    African Journals Online (AJOL)

    Comparative phytochemical and growth inhibitory studies on the leaf and root bark extracts of securinega Virosa (roxb ex. Willd) baill ... The growth inhibitory tests were carried out between 1-30 mg/ in a period of 24-96 h while the phytochemical screening was carried out on the plant parts using standard methods. At 24 h ...

  13. Syllable Frequency and Spoken Word Recognition: An Inhibitory Effect.

    Science.gov (United States)

    González-Alvarez, Julio; Palomar-García, María-Angeles

    2016-08-01

    Research has shown that syllables play a relevant role in lexical access in Spanish, a shallow language with a transparent syllabic structure. Syllable frequency has been shown to have an inhibitory effect on visual word recognition in Spanish. However, no study has examined the syllable frequency effect on spoken word recognition. The present study tested the effect of the frequency of the first syllable on recognition of spoken Spanish words. A sample of 45 young adults (33 women, 12 men; M = 20.4, SD = 2.8; college students) performed an auditory lexical decision on 128 Spanish disyllabic words and 128 disyllabic nonwords. Words were selected so that lexical and first syllable frequency were manipulated in a within-subject 2 × 2 design, and six additional independent variables were controlled: token positional frequency of the second syllable, number of phonemes, position of lexical stress, number of phonological neighbors, number of phonological neighbors that have higher frequencies than the word, and acoustical durations measured in milliseconds. Decision latencies and error rates were submitted to linear mixed models analysis. Results showed a typical facilitatory effect of the lexical frequency and, importantly, an inhibitory effect of the first syllable frequency on reaction times and error rates. © The Author(s) 2016.

  14. An analysis of inhibitory functioning in individuals with chronic posttraumatic stress disorder.

    Science.gov (United States)

    Echiverri-Cohen, Aileen M; Zoellner, Lori A; Ho, William; Husain, Jawad

    2016-01-01

    Cognitive abnormalities in posttraumatic stress disorder (PTSD) may be a function of underlying inhibitory deficits. Prepulse inhibition (PPI) and attentional blink (AB) are paradigms thought to assess inhibition. Using a sample of 28 individuals with PTSD compared to 20 trauma-exposed and 19 healthy individuals, PPI was examined using white noise that was preceded by a tone, and AB was examined using a presentation of letters in a stream of numbers. Relative to the control group, the PTSD and trauma-exposed groups did not follow the u-shaped pattern in AB, suggesting trauma-exposure and subsequent PTSD are associated with similar impairment in attention. Individuals with PTSD showed reduced PPI compared to trauma-exposed and healthy individuals, suggesting individuals with PTSD exhibit faulty automatic processing. For individuals with PTSD, PTSD severity was associated with a decline in PPI. These findings suggest a general faulty inhibitory mechanism associated with trauma exposure and PTSD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract.

    Science.gov (United States)

    Padilla-Camberos, Eduardo; Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos; Allen, Kirk

    2015-01-01

    Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

  16. Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract

    Directory of Open Access Journals (Sweden)

    Eduardo Padilla-Camberos

    2015-01-01

    Full Text Available Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

  17. Optimization of inhibitory decision rules relative to length and coverage

    KAUST Repository

    Alsolami, Fawaz; Chikalov, Igor; Moshkov, Mikhail; Zielosko, Beata

    2012-01-01

    The paper is devoted to the study of algorithms for optimization of inhibitory rules relative to the length and coverage. In contrast with usual rules that have on the right-hand side a relation "attribute ≠ value", inhibitory rules have a relation

  18. Bacteriocin-like inhibitory activities of seven Lactobacillus delbrueckii subsp. bulgaricus strains against antibiotic susceptible and resistant Helicobacter pylori strains.

    Science.gov (United States)

    Boyanova, L; Gergova, G; Markovska, R; Yordanov, D; Mitov, I

    2017-12-01

    The aim of the study was to detect anti-Helicobacter pylori activity of seven Lactobacillus delbrueckii subsp. bulgaricus (GLB) strains by four cell-free supernatant (CFS) types. Activity of non-neutralized and non-heat-treated (CFSs1), non-neutralized and heat-treated (CFSs2), pH neutralized, catalase-treated and non-heat-treated (CFSs3), or neutralized, catalase- and heat-treated (CFSs4) CFSs against 18 H. pylori strains (11 of which with antibiotic resistance) was evaluated. All GLB strains produced bacteriocin-like inhibitory substances (BLISs), the neutralized CFSs of two GLB strains inhibited >81% of test strains and those of four GLB strains were active against >71% of antibiotic resistant strains. Two H. pylori strains were BLIS resistant. The heating did not reduce the CFS activity. Briefly, all GLB strains evaluated produced heat-stable BLISs, although GLB and H. pylori strain susceptibility patterns exhibited differences. Bacteriocin-like inhibitory substance activity can be an advantage for the probiotic choice for H. pylori infection control. In this study, anti-Helicobacter pylori activity of seven Lactobacillus delbrueckii subsp. bulgaricus (GLB) strains was evaluated by four cell-free supernatant (CFS) types. The GLB strains produced heat-stable bacteriocin-like inhibitory substances (BLISs) with a strong anti-H. pylori activity and some neutralized, catalase- and heat-treated CFSs inhibited >83% of the test strains. Bacteriocin-like inhibitory substance production of GLB strains can render them valuable probiotics in the control of H. pylori infection. © 2017 The Society for Applied Microbiology.

  19. INHIBITORY EFFECT OF SALVIA SCLAREA

    African Journals Online (AJOL)

    rakoe

    2011-11-02

    Nov 2, 2011 ... This study demonstrated anti-herpes simplex virus (HSV) activity of lavender, sage and ... Green monkey kidney cells were protected from HSV-2 infection by ... The highest inhibitory effect against HSV-2 was observed after treatment ..... some nuclear-replicating eukaryotic DNA viruses with large genomes.

  20. Effects of Heat, pH, and Gamma Irradiation Treatments on Lipase Inhibitory Activity of Sargassum thunbergii Ethanol Extract

    International Nuclear Information System (INIS)

    Kim, D.H.; Kim, K.B.W.R.; Kim, M.J.; Sunwoo, C.; Jung, S.A.; Kim, H.J.; Jeong, D.H.; Ahn, D.H.; Kim, T.W.; Cho, Y.J.

    2012-01-01

    Inhibitory activity of Sagassum thunbergii (ST) against porcine pancreatic lipase was assessed after heat treatment, pH changes, and gamma irradiation. This analysis revealed that the ST ethanol extract exhibited high lipase inhibitory activity (37.37%) at 5 mg/mL. The ST ethanol extract was treated with heat at 60°C for 10, 30, and 60 min; 80 and 100°C for 10 and 20 min; and 121°C for 15 min, pH (2, 4, 6, 8 and 10) and γ -irradiation (3, 7 and 20 kGy). The lipase inhibitory activity of the ST ethanol extract increased in all heat treatments, especially at 121°C for 15 min (51.55%) compared with the control. With regard to pH stability, the ST ethanol extract showed no significant changes at pH 4 ~ 8, but somewhat decreased inhibitory activity was revealed at pH 2 (26.25%) and 10 (29.93%). On the other hand, the ST ethanol extract was not affected by γ -irradiation treatment conditions used in this study. These results suggest that ST has a potential role as a functional food agent. (author)

  1. Brain Injury-Induced Synaptic Reorganization in Hilar Inhibitory Neurons Is Differentially Suppressed by Rapamycin.

    Science.gov (United States)

    Butler, Corwin R; Boychuk, Jeffery A; Smith, Bret N

    2017-01-01

    Following traumatic brain injury (TBI), treatment with rapamycin suppresses mammalian (mechanistic) target of rapamycin (mTOR) activity and specific components of hippocampal synaptic reorganization associated with altered cortical excitability and seizure susceptibility. Reemergence of seizures after cessation of rapamycin treatment suggests, however, an incomplete suppression of epileptogenesis. Hilar inhibitory interneurons regulate dentate granule cell (DGC) activity, and de novo synaptic input from both DGCs and CA3 pyramidal cells after TBI increases their excitability but effects of rapamycin treatment on the injury-induced plasticity of interneurons is only partially described. Using transgenic mice in which enhanced green fluorescent protein (eGFP) is expressed in the somatostatinergic subset of hilar inhibitory interneurons, we tested the effect of daily systemic rapamycin treatment (3 mg/kg) on the excitability of hilar inhibitory interneurons after controlled cortical impact (CCI)-induced focal brain injury. Rapamycin treatment reduced, but did not normalize, the injury-induced increase in excitability of surviving eGFP+ hilar interneurons. The injury-induced increase in response to selective glutamate photostimulation of DGCs was reduced to normal levels after mTOR inhibition, but the postinjury increase in synaptic excitation arising from CA3 pyramidal cell activity was unaffected by rapamycin treatment. The incomplete suppression of synaptic reorganization in inhibitory circuits after brain injury could contribute to hippocampal hyperexcitability and the eventual reemergence of the epileptogenic process upon cessation of mTOR inhibition. Further, the cell-selective effect of mTOR inhibition on synaptic reorganization after CCI suggests possible mechanisms by which rapamycin treatment modifies epileptogenesis in some models but not others.

  2. COMPARATIVE EVALUATION OF INHIBITORY ACTIVITY OF ...

    African Journals Online (AJOL)

    Osondu

    2013-02-26

    Feb 26, 2013 ... especially the four bacteria isolates used in this study are present in the epiphgram of both normal and ... Keyword: Albino snail, Archachatina marginata, Inhibitory activity, Epiphgram, Bacteria isolate. Introduction .... evolution.

  3. Inhibitory Effect of Gamma-Irradiated Chitosan on the Growth of Denitrifiers

    Directory of Open Access Journals (Sweden)

    Javier Vilcáez

    2009-01-01

    Full Text Available In order to find an environmentally benign substitute to hazardous inhibitory agents, the inhibitory effect of -irradiated chitosans against a mixed culture of denitrifying bacteria was experimentally evaluated. Unlike other studies using pure aerobic cultures, the observed effect was not a complete inhibition but a transient inhibition reflected by prolonged lag phases and reduced growth rates. Raw chitosan under acid conditions (pH 6.3 exerted the strongest inhibition followed by the 100 kGy and 500 kGy irradiated chitosans, respectively. Therefore, because the molecular weight of chitosan decreases with the degree of -irradiation, the inhibitory properties of chitosan due to its high molecular weight were more relevant than the inhibitory properties gained due to the modification of the surface charge and/or chemical structure by -irradiation. High dosage of -irradiated appeared to increase the growth of mixed denitrifying bacteria in acid pH media. However, in neutral pH media, high dosage of -irradiation appeared to enhance the inhibitory effect of chitosan.

  4. Inhibitory Effect of Corn Silk on Skin Pigmentation

    OpenAIRE

    Sang Yoon Choi; Yeonmi Lee; Sung Soo Kim; Hyun Min Ju; Ji Hwoon Baek; Chul-Soo Park; Dong-Hyuk Lee

    2014-01-01

    In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin prod...

  5. Identification of dipeptidyl peptidase-IV inhibitory peptides from mare whey protein hydrolysates.

    Science.gov (United States)

    Song, J J; Wang, Q; Du, M; Ji, X M; Mao, X Y

    2017-09-01

    Inhibition of dipeptidyl peptidase-IV (DPP-IV) activity is a promising strategy for treatment of type 2 diabetes. In the current study, DPP-IV inhibitory peptides were identified from mare whey protein hydrolysates obtained by papain. The results showed that all the mare whey protein hydrolysates obtained at various hydrolysis durations possessed more potent DPP-IV inhibitory activity compared with intact whey protein. The 4-h hydrolysates showed the greatest DPP-IV inhibitory activity with half-maximal inhibitory concentration of 0.18 mg/mL. The 2 novel peptides from 4-h hydrolysate fractions separated by successive chromatographic steps were characterized by liquid chromatography-electrospray ionization tandem mass spectrometry. The novel peptides Asn-Leu-Glu-Ile-Ile-Leu-Arg and Thr-Gln-Met-Val-Asp-Glu-Glu-Ile-Met-Glu-Lys-Phe-Arg, which corresponded to β-lactoglobulin 1 f(71-77) and β-lactoglobulin 1 f(143-155), demonstrated DPP-IV inhibitory activity with half-maximal inhibitory concentrations of 86.34 and 69.84 μM, respectively. The DPP-IV inhibitory activity of the 2 peptides was retained or even improved after simulated gastrointestinal digestion in vitro. Our findings indicate that mare whey protein-derived peptides may possess potential as functional food ingredients in the management of type 2 diabetes. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. A systematic review and evaluation of inhibitory stimulus control procedures as a treatment for stereotyped behavior among individuals with autism.

    Science.gov (United States)

    Lydon, Sinéad; Moran, Laura; Healy, Olive; Mulhern, Teresa; Enright Young, Kerie

    2017-11-01

    Stereotypy is pervasive among persons with autism and may impact negatively on social inclusion and learning. The implementation of resource-intensive behavioral interventions to decrease these behaviors has been questioned. Inhibitory stimulus control procedures (ISCPs) comprise a type of antecedent-based intervention that has been proposed as an effective treatment approach for stereotypy but has received limited research attention to date. The current systematic review sought to examine and synthesize the literature reporting applications of ISCPs in the treatment of stereotypy among persons with autism. Treatment outcomes were analyzed quantitatively and the status of ISCPs as evidence-based practice was evaluated in accordance with the National Autism Center's National Standards Report guidelines. A total of 11 studies were reviewed with results indicating that ISCPs constituted an emerging treatment for the stereotypy exhibited by persons with autism. ISCPs comprise a promising intervention for stereotyped behavior but further research is required.

  7. Evaluation of Traditional Indian Antidiabetic Medicinal Plants for Human Pancreatic Amylase Inhibitory Effect In Vitro

    Directory of Open Access Journals (Sweden)

    Sudha Ponnusamy

    2011-01-01

    Full Text Available Pancreatic α-amylase inhibitors offer an effective strategy to lower the levels of post prandial hyperglycemia via control of starch breakdown. Eleven Ayurvedic Indian medicinal plants with known hypoglycemic properties were subjected to sequential solvent extraction and tested for α-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic α-amylase. Analysis of 91 extracts, showed that 10 exhibited strong Human Pancreatic Amylase (HPA inhibitory potential. Of these, 6 extracts showed concentration dependent inhibition with IC50 values, namely, cold and hot water extracts from Ficus bengalensis bark (4.4 and 125 μgmL-1, Syzygium cumini seeds (42.1 and 4.1 μgmL-1, isopropanol extracts of Cinnamomum verum leaves (1.0 μgmL-1 and Curcuma longa rhizome (0.16 μgmL-1. The other 4 extracts exhibited concentration independent inhibition, namely, methanol extract of Bixa orellana leaves (49 μgmL-1, isopropanol extract from Murraya koenigii leaves (127 μgmL-1, acetone extracts from C. longa rhizome (7.4 μgmL-1 and Tribulus terrestris seeds (511 μgmL-1. Thus, the probable mechanism of action of the above fractions is due to their inhibitory action on HPA, thereby reducing the rate of starch hydrolysis leading to lowered glucose levels. Phytochemical analysis revealed the presence of alkaloids, proteins, tannins, cardiac glycosides, flavonoids, saponins and steroids as probable inhibitory compounds.

  8. Temporal changes in cortical activation during conditioned pain modulation (CPM), a LORETA study.

    Science.gov (United States)

    Moont, Ruth; Crispel, Yonatan; Lev, Rina; Pud, Dorit; Yarnitsky, David

    2011-07-01

    For most healthy subjects, both subjective pain ratings and pain-evoked potentials are attenuated under conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls, or DNIC). Although essentially spinal-bulbar, this inhibition is under cortical control. This is the first study to observe temporal as well as spatial changes in cortical activations under CPM. Specifically, we aimed to investigate the interplay of areas involved in the perception and processing of pain and those involved in controlling descending inhibition. We examined brief consecutive poststimulus time windows of 50 ms using a method of source-localization from pain evoked potentials, sLORETA. This enabled determination of dynamic changes in localized cortical generators evoked by phasic noxious heat stimuli to the left volar forearm in healthy young males, with and without conditioning hot-water pain to the right hand. We found a CPM effect characterized by an initial increased activation in the orbitofrontal cortex (OFC) and amygdala at 250-300 ms poststimulus, which was correlated with the extent of psychophysical pain reduction. This was followed by reduced activations in the primary and secondary somatosensory cortices, supplementary motor area, posterior insula, and anterior cingulate cortex from 400 ms poststimulus. Our findings show that the prefrontal pain-controlling areas of OFC and amygdala increase their activity in parallel with subjective pain reduction under CPM, and that this increased activity occurs prior to reductions in activations of the pain sensory areas. In conclusion, achieving pain inhibition by the CPM process seems to be under control of the OFC and the amygdala. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  9. Disruption of Fgf13 causes synaptic excitatory-inhibitory imbalance and genetic epilepsy and febrile seizures plus.

    Science.gov (United States)

    Puranam, Ram S; He, Xiao Ping; Yao, Lijun; Le, Tri; Jang, Wonjo; Rehder, Catherine W; Lewis, Darrell V; McNamara, James O

    2015-06-10

    We identified a family in which a translocation between chromosomes X and 14 was associated with cognitive impairment and a complex genetic disorder termed "Genetic Epilepsy and Febrile Seizures Plus" (GEFS(+)). We demonstrate that the breakpoint on the X chromosome disrupted a gene that encodes an auxiliary protein of voltage-gated Na(+) channels, fibroblast growth factor 13 (Fgf13). Female mice in which one Fgf13 allele was deleted exhibited hyperthermia-induced seizures and epilepsy. Anatomic studies revealed expression of Fgf13 mRNA in both excitatory and inhibitory neurons of hippocampus. Electrophysiological recordings revealed decreased inhibitory and increased excitatory synaptic inputs in hippocampal neurons of Fgf13 mutants. We speculate that reduced expression of Fgf13 impairs excitability of inhibitory interneurons, resulting in enhanced excitability within local circuits of hippocampus and the clinical phenotype of epilepsy. These findings reveal a novel cause of this syndrome and underscore the powerful role of FGF13 in control of neuronal excitability. Copyright © 2015 the authors 0270-6474/15/358866-16$15.00/0.

  10. Histamine release inhibitory activity of Piper nigrum leaf.

    Science.gov (United States)

    Hirata, Noriko; Naruto, Shunsuke; Inaba, Kazunori; Itoh, Kimihisa; Tokunaga, Masashi; Iinuma, Munekazu; Matsuda, Hideaki

    2008-10-01

    Oral administration of a methanolic extract of Piper nigrum leaf (PN-ext, 50, 200 and 500 mg/kg) showed a potent dose-dependent inhibition of dinitrofluorobenzene (DNFB)-induced cutaneous reaction at 1 h [immediate phase response (IPR)] after and 24 h [late phase response (LPR)] after DNFB challenge in mice which were passively sensitized with anti-dinitrophenyl (DNP) IgE antibody. Ear swelling inhibitory effect of PN-ext (50, 200 and 500 mg/kg, per os (p.o.)) on very late phase response (vLPR) in the model mice was significant but weaker than that on IPR. Oral administration of PN-ext (50, 200 and 500 mg/kg for 7 d) inhibited picryl chloride (PC)-induced ear swelling in PC sensitized mice. PN-ext exhibited in vitro inhibitory effect on compound 48/80-induced histamine release from rat peritoneal mast cells. Two lignans of PN-ext, (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2), were identified as major active principles having histamine release inhibitory activity.

  11. Caffeine Does Not Modulate Inhibitory Control

    Science.gov (United States)

    Tieges, Zoe; Snel, Jan; Kok, Albert; Ridderinkhof, K. Richard

    2009-01-01

    The effects of a 3 mg/kg body weight (BW) dose of caffeine were assessed on behavioral indices of response inhibition. To meet these aims, we selected a modified AX version of the Continuous Performance Test (CPT), the stop task, and the flanker task. In three double-blind, placebo-controlled, within-subjects experiments, these tasks were…

  12. Randomized controlled trial of maternal omega-3 long-chain PUFA supplementation during pregnancy and early childhood development of attention, working memory, and inhibitory control.

    Science.gov (United States)

    Gould, Jacqueline F; Makrides, Maria; Colombo, John; Smithers, Lisa G

    2014-04-01

    Docosahexaenoic acid (DHA) accumulates in the hippocampus and frontal lobes of the fetal brain during the last trimester of pregnancy. These areas of the brain contribute to attention and working memory and inhibitory control (WMIC). We evaluated the effect of maternal omega-3 (n-3) long-chain polyunsaturated fatty acid supplementation in pregnancy on child attention and WMIC. A total of 185 term-born children of mothers who were randomly allocated to consume 800 mg DHA/d (treatment) or a placebo (control) from ∼20 wk of gestation until birth were assessed with multiple measures of attention and WMIC at a mean (± SD) of 27 ± 2 mo. Primary outcomes were the average time it took to be distracted when playing with a toy (distractibility) and the accuracy of remembering a new hiding location while inhibiting a learned response to search in the previous location (WMIC). Assessments were completed by 81 children in the treatment group (mean ± SD age: 835 ± 50.4 d) and 77 children in the control group (839 ± 65.6 d). There was no effect of supplementation on primary outcomes [distractibility mean difference: -0.2 s (95% CI: -0.7, 0.4 s); WMIC mean difference: 8.9 mm (95% CI: -10.6, 28.3 mm)]. There was no difference between DHA-supplemented and control groups except that treatment-group children looked away from the toys fewer times than controls when presented with multiple toys competing for attention but less accurately remembered a repeated hiding location. These secondary effects were not consistent with any other outcomes and may have been a result of chance. Cord plasma DHA was not consistently associated with attention and WMIC. Maternal DHA supplementation during pregnancy does not enhance attention or WMIC in term-born preschoolers. The DHA for Maternal and Infant Outcomes trial was registered at www.anzctr.org.au as ACTRN1260500056906.

  13. Chemical Composition and α-Glucosidase Inhibitory Activity of Vietnamese Citrus Peels Essential Oils

    Directory of Open Access Journals (Sweden)

    Nguyen Hai Dang

    2016-01-01

    Full Text Available Background. Inhibition of α-glucosidase is an important factor to control postprandial hyperglycemia in type 2 diabetes mellitus. Citrus essential oils (CEO are among the most widely used essential oils, and some of them exhibited promising antidiabetic effect. However, the α-glucosidase inhibition of CEO has not been investigated so far. The present work aims to evaluate the α-glucosidase inhibition of essential oils from six Vietnamese Citrus peels. Methods. The chemical composition of essential oils obtained by hydrodistillation from six Citrus peels was analyzed by GC-MS. All essential oils were tested for their inhibitory activity on α-glucosidase using p-nitrophenyl-α-D-glucopyranoside as substrate. Results. In Buddha’s hand and lime peels, the major components were limonene (59.0–61.31% and γ-terpinene (13.98–23.84% while limonene (90.95–95.74% was most abundant in pomelo, orange, tangerine, and calamondin peels. Among the essential oils, the Buddha’s hand oil showed the most significant α-glucosidase inhibitory effect with the IC50 value of 412.2 μg/mL. The combination of the Buddha’s hand essential oil and the antidiabetic drug acarbose increased the inhibitory effect. Conclusions. The results suggested the potential use of Buddha’s hand essential oil as an alternative in treatment of type 2 diabetes mellitus.

  14. On minimal inhibitory rules for almost all k-valued information systems

    KAUST Repository

    Moshkov, Mikhail; Skowron, Andrzej; Suraj, Zbigniew

    2009-01-01

    The minimal inhibitory rules for information systems can be used for construction of classifiers. We show that almost all information systems from a certain large class of information systems have relatively short minimal inhibitory rules. However

  15. Sleep supports inhibitory operant conditioning memory in Aplysia.

    Science.gov (United States)

    Vorster, Albrecht P A; Born, Jan

    2017-06-01

    Sleep supports memory consolidation as shown in mammals and invertebrates such as bees and Drosophila. Here, we show that sleep's memory function is preserved in Aplysia californica with an even simpler nervous system. Animals performed on an inhibitory conditioning task ("learning that a food is inedible") three times, at Training, Retrieval 1, and Retrieval 2, with 17-h intervals between tests. Compared with Wake animals, remaining awake between Training and Retrieval 1, Sleep animals with undisturbed post-training sleep, performed significantly better at Retrieval 1 and 2. Control experiments testing retrieval only after ∼34 h, confirmed the consolidating effect of sleep occurring within 17 h after training. © 2017 Vorster and Born; Published by Cold Spring Harbor Laboratory Press.

  16. Lactoferricin B-derived peptides with inhibitory effects on ECE-dependent vasoconstriction.

    Science.gov (United States)

    Fernández-Musoles, Ricardo; López-Díez, José Javier; Torregrosa, Germán; Vallés, Salvador; Alborch, Enrique; Manzanares, Paloma; Salom, Juan B

    2010-10-01

    Endothelin-converting enzyme (ECE), a key peptidase in the endothelin (ET) system, cleaves inactive big ET-1 to produce active ET-1, which binds to ET(A) receptors to exert its vasoconstrictor and pressor effects. ECE inhibition could be beneficial in the treatment of hypertension. In this study, a set of eight lactoferricin B (LfcinB)-derived peptides, previously characterized in our laboratory as angiotensin-converting enzyme (ACE) inhibitory peptides, was examined for their inhibitory effects on ECE. In vitro inhibitory effects on ECE activity were assessed using both the synthetic fluorogenic peptide substrate V (FPS V) and the natural substrate big ET-1. To study vasoactive effects, an ex vivo functional assay was developed using isolated rabbit carotid artery segments. With FPS V, only four LfcinB-derived peptides induced inhibition of ECE activity, whereas the eight peptides showed ECE inhibitory effects with big ET-1 as substrate. Regarding the ex vivo assays, six LfcinB-derived peptides showed inhibition of big ET-1-induced, ECE-dependent vasoconstriction. A positive correlation between the inhibitory effects of LfcinB-derived peptides on ECE activity when using big ET-1 and the inhibitory effects on ECE-dependent vasoconstriction was shown. ECE-independent vasoconstriction induced by ET-1 was not affected, thus discarding effects of LfcinB-derived peptides on ET(A) receptors or intracellular signal transduction mechanisms. In conclusion, a combined in vitro and ex vivo method to assess the effects of potentially antihypertensive peptides on the ET system has been developed and applied to show the inhibitory effects on ECE-dependent vasoconstriction of six LfcinB-derived peptides, five of which were dual vasopeptidase (ACE/ECE) inhibitors. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Testosterone 5alpha-reductase inhibitory active constituents of Piper nigrum leaf.

    Science.gov (United States)

    Hirata, Noriko; Tokunaga, Masashi; Naruto, Shunsuke; Iinuma, Munekazu; Matsuda, Hideaki

    2007-12-01

    Previously we reported that Piper nigrum leaf extract showed a potent stimulation effect on melanogenesis and that (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2) were isolated as active constituents. As a part of our continuous studies on Piper species for the development of cosmetic hair-care agents, testosterone 5alpha-reductase inhibitory activity of aqueous ethanolic extracts obtained from several different parts of six Piper species, namely Piper nigrum, P. methysticum, P. betle, P. kadsura, P. longum, and P. cubeba, were examined. Among them, the extracts of P. nigrum leaf, P. nigrum fruit and P. cubeba fruit showed potent inhibitory activity. Activity-guided fractionation of P. nigrum leaf extract led to the isolation of 1 and 2. Fruits of P. cubeba contain 1 as a major lignan, thus inhibitory activity of the fruit may be attributable to 1. As a result of further assay on other known constituents of the cited Piper species, it was found that piperine, a major alkaloid amide of P. nigrum fruit, showed potent inhibitory activity, thus a part of the inhibitory activity of P. nigrum fruit may depend on piperine. The 5alpha-reductase inhibitory activities of 1 and piperine were found for the first time. In addition, the P. nigrum leaf extract showed in vivo anti-androgenic activity using the hair regrowth assay in testosterone sensitive male C57Black/6CrSlc strain mice.

  18. Potent Inhibitory Effect of Chinese Dietary Spices on Fatty Acid Synthase.

    Science.gov (United States)

    Jiang, Bing; Liang, Yan; Sun, Xuebing; Liu, Xiaoxin; Tian, Weixi; Ma, Xiaofeng

    2015-09-01

    Dietary spices have been adopted in cooking since ancient times to enhance flavor and also as food preservatives and disease remedies. In China, the use of spices and other aromatic plants as food flavoring is an integral part of dietary behavior, but relatively little is known about their functions. Fatty acid synthase (FAS) has been recognized as a remedy target, and its inhibitors might be applied in disease treatment. The present work was designed to assess the inhibitory activities on FAS of spices extracts in Chinese menu. The in vitro inhibitory activities on FAS of 22 extracts of spices were assessed by spectrophotometrically monitoring oxidation of NADPH at 340 nm. Results showed that 20 spices extracts (90.9 %) exhibited inhibitory activities on FAS, with half inhibition concentration (IC(50)) values ranging from 1.72 to 810.7 μg/ml. Among them, seven spices showed strong inhibitory effect with IC(50) values lower than 10 μg/ml. These findings suggest that a large proportion of the dietary spices studied possess promising inhibitory activities on FAS, and subsequently might be applied in the treatment of obesity and obesity-related human diseases.

  19. Preparation of ACE Inhibitory Peptides from Mytilus coruscus Hydrolysate Using Uniform Design

    Directory of Open Access Journals (Sweden)

    Jin-Chao Wu

    2013-01-01

    Full Text Available The angiotensin-I-converting enzyme (ACE inhibitory peptides from mussel, Mytilus coruscus, were investigated and the variable factors, protease concentration, hydrolysis time, pH, and temperature, were optimized using Uniform Design, a new statistical experimental method. The results proved that the hydrolysate of alkali proteases had high ACE-inhibitory activity, especially the alkali protease E1. Optimization by Uniform Design showed that the best hydrolysis conditions for preparation of ACE-inhibitory peptides from Mytilus coruscus were protease concentration of 36.0 U/mL, hydrolysis time of 2.7 hours, pH 8.2, and Temperature at 59.5°C, respectively. The verification experiments under optimum conditions showed that the ACE-inhibitory activity (91.3% were agreed closely with the predicted activity of 90.7%. The amino acid composition analysis of Mytilus coruscus ACE-inhibitory peptides proved that it had high percent of lysine, leucine, glycine, aspartic acid, and glutamic acid.

  20. Evidence for two concurrent inhibitory mechanisms during response preparation

    Science.gov (United States)

    Duque, Julie; Lew, David; Mazzocchio, Riccardo; Olivier, Etienne; Ivry, Richard B.

    2010-01-01

    Inhibitory mechanisms are critically involved in goal-directed behaviors. To gain further insight into how such mechanisms shape motor representations during response preparation, motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) and H-reflexes were recorded from left hand muscles during choice reaction time tasks. The imperative signal, which indicated the required response, was always preceded by a preparatory cue. During the post-cue delay period, left MEPs were suppressed when the left hand had been cued for the forthcoming response, suggestive of a form of inhibition specifically directed at selected response representations. H-reflexes were also suppressed on these trials, indicating that the effects of this inhibition extend to spinal circuits. In addition, left MEPs were suppressed when the right hand was cued, but only when left hand movements were a possible response option before the onset of the cue. Notably, left hand H-reflexes were not modulated on these trials, consistent with a cortical locus of inhibition that lowers the activation of task-relevant, but non-selected responses. These results suggest the concurrent operation of two inhibitory mechanisms during response preparation: one decreases the activation of selected responses at the spinal level, helping to control when selected movements should be initiated by preventing their premature release; a second, upstream mechanism helps to determine what response to make during a competitive selection process. PMID:20220014

  1. Lactoferricin-related peptides with inhibitory effects on ACE-dependent vasoconstriction.

    Science.gov (United States)

    Centeno, José M; Burguete, María C; Castelló-Ruiz, María; Enrique, María; Vallés, Salvador; Salom, Juan B; Torregrosa, Germán; Marcos, José F; Alborch, Enrique; Manzanares, Paloma

    2006-07-26

    A selection of lactoferricin B (LfcinB)-related peptides with an angiotensin I-converting enzyme (ACE) inhibitory effect have been examined using in vitro and ex vivo functional assays. Peptides that were analyzed included a set of sequence-related antimicrobial hexapeptides previously reported and two representative LfcinB-derived peptides. In vitro assays using hippuryl-L-histidyl-L-leucine (HHL) and angiotensin I as substrates allowed us to select two hexapeptides, PACEI32 (Ac-RKWHFW-NH2) and PACEI34 (Ac-RKWLFW-NH2), and also a LfcinB-derived peptide, LfcinB17-31 (Ac-FKCRRWQWRMKKLGA-NH2). Ex vivo functional assays using rabbit carotid arterial segments showed PACEI32 (both D- and L-enantiomers) and LfcinB17-31 have inhibitory effects on ACE-dependent angiotensin I-induced contraction. None of the peptides exhibited in vitro ACE inhibitory activity using bradykinin as the substrate. In conclusion, three bioactive lactoferricin-related peptides exhibit inhibitory effects on both ACE activity and ACE-dependent vasoconstriction with potential to modulate hypertension that deserves further investigation.

  2. Modifying Yeast Tolerance to Inhibitory Conditions of Ethanol Production Processes

    DEFF Research Database (Denmark)

    Caspeta, Luis; Castillo, Tania; Nielsen, Jens

    2015-01-01

    Saccharomyces cerevisiae strains having a broad range of substrate utilization, rapid substrate consumption, and conversion to ethanol, as well as good tolerance to inhibitory conditions are ideal for cost-competitive ethanol production from lignocellulose. A major drawback to directly design S....... cerevisiae tolerance to inhibitory conditions of lignocellulosic ethanol production processes is the lack of knowledge about basic aspects of its cellular signaling network in response to stress. Here, we highlight the inhibitory conditions found in ethanol production processes, the targeted cellular...... functions, the key contributions of integrated -omics analysis to reveal cellular stress responses according to these inhibitors, and current status on design-based engineering of tolerant and efficient S. cerevisiae strains for ethanol production from lignocellulose....

  3. Pain-related increase of excitatory transmission and decrease of inhibitory transmission in the central nucleus of the amygdala are mediated by mGluR1

    Directory of Open Access Journals (Sweden)

    Neugebauer Volker

    2010-12-01

    Full Text Available Abstract Neuroplasticity in the central nucleus of the amygdala (CeA, particularly its latero-capsular division (CeLC, is an important contributor to the emotional-affective aspects of pain. Previous studies showed synaptic plasticity of excitatory transmission to the CeLC in different pain models, but pain-related changes of inhibitory transmission remain to be determined. The CeLC receives convergent excitatory inputs from the parabrachial nucleus in the brainstem and from the basolateral amygdala (BLA. In addition, feedforward inhibition of CeA neurons is driven by glutamatergic projections from the BLA area to a cluster of GABAergic neurons in the intercalated cell masses (ITC. Using patch-clamp in rat brain slices we measured monosynaptic excitatory postsynaptic currents (EPSCs and polysynaptic inhibitory currents (IPSCs that were evoked by electrical stimulation in the BLA. In brain slices from arthritic rats, input-output functions of excitatory synaptic transmission were enhanced whereas inhibitory synaptic transmission was decreased compared to control slices from normal untreated rats. A non-NMDA receptor antagonist (NBQX blocked the EPSCs and reduced the IPSCs, suggesting that non-NMDA receptors mediate excitatory transmission and also contribute to glutamate-driven feed-forward inhibition of CeLC neurons. IPSCs were blocked by a GABAA receptor antagonist (bicuculline. Bicuculline increased EPSCs under normal conditions but not in slices from arthritic rats, which indicates a loss of GABAergic control of excitatory transmission. A metabotropic glutamate receptor subtype 1 (mGluR1 antagonist (LY367385 reversed both the increase of excitatory transmission and the decrease of inhibitory transmission in the arthritis pain model but had no effect on basal synaptic transmission in control slices from normal rats. The inhibitory effect of LY367385 on excitatory transmission was blocked by bicuculline suggesting the involvement of a GABAergic

  4. Antifeedant, insecticidal and growth inhibitory activities of selected plant oils on black cutworm, Agrotis ipsilon (Hufnagel (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Alagarmalai Jeyasankar

    2012-05-01

    Full Text Available Objective: To evaluate antifeedant, insecticidal and insect growth inhibitory activities of eucalyptus oil (Eucalyptus globules and gaultheria oil (Gaultheria procumbens L. against black cutworm, Agrotis ipsilon. Methods: Antifeedant, insecticidal and growth inhibitory activities of eucalyptus oil and gaultheria oil were tested against black cutworm, A. ipsilon. Results: Significant antifeedant activity was found in eucalyptus oil (96.24% where as the highest insecticidal activity was noticed in gaultheria oil (86.92%. Percentages of deformities were highest on gaultheria oil treated larvae and percentage of adult emergence was deteriorated also by gaultheria oil. Conclusions: These plants oil has potential to serve as an alternative eco-friendly control of insect pest.

  5. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons

    Directory of Open Access Journals (Sweden)

    Chiaki Murayama

    2015-08-01

    Full Text Available Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH, a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF in cultured rat dorsal root ganglion (DRG neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control, a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in “itch-scratch” animal models is under investigation.

  6. The effect of Helicobacter pylori eradication on macrophage migration inhibitory factor, C-reactive protein and fetuin-a levels

    Directory of Open Access Journals (Sweden)

    Levent Kebapcilar

    2010-06-01

    Full Text Available OBJECTIVES: To determine the effect of Helicobacter pylori (H. pylori eradication on blood levels of high-sensitivity C-reactive protein (hs-CRP, macrophage migration inhibitory factor and fetuin-A in patients with dyspepsia who are concurrently infected with H. pylori. METHODS: H.pylori infection was diagnosed based on the 14C urea breath test (UBT and histology. Lansoprazole 30 mg twice daily, amoxicillin 1 g twice daily, and clarithromycin 500 mg twice daily were given to all infected patients for 14 days; 14C UBT was then re-measured. In 30 subjects, migration inhibitory factor, fetuin-A and hs-CRP levels were examined before and after the eradication of H. pylori infection and compared to levels in 30 healthy subjects who tested negative for H. pylori infection. RESULTS: Age and sex distribution were comparable between patients and controls. Migration inhibitory factor and hs-CRP levels were higher, and fetuin-A levels were lower, in H. pylori-infected patients (p0.05. CONCLUSION: These findings suggest that H. pylori eradication reduces the levels of pro-inflammatory cytokines such as migration inhibitory factor and hs-CRP and also results in a significant increase in anti-inflammatory markers such as fetuin-A.

  7. Inhibitory Effects of Spices on Biogenic Amine Accumulation during Fish Sauce Fermentation.

    Science.gov (United States)

    Zhou, Xuxia; Qiu, Mengting; Zhao, Dandan; Lu, Fei; Ding, Yuting

    2016-04-01

    The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce. © 2016 Institute of Food Technologists®

  8. Dendritic cell co-stimulatory and co-inhibitory markers in chronic HCV: An Egyptian study

    Science.gov (United States)

    Fouad, Hanan; Raziky, Maissa Saeed El; Aziz, Rasha Ahmed Abdel; Sabry, Dina; Aziz, Ghada Mahmoud Abdel; Ewais, Manal; Sayed, Ahmed Reda

    2013-01-01

    AIM: To assess co-stimulatory and co-inhibitory markers of dendritic cells (DCs) in hepatitis C virus (HCV) infected subjects with and without uremia. METHODS: Three subject groups were included in the study: group 1 involved 50 control subjects, group 2 involved 50 patients with chronic HCV infection and group 3 involved 50 HCV uremic subjects undergoing hemodialysis. CD83, CD86 and CD40 as co-stimulatory markers and PD-L1 as a co-inhibitory marker were assessed in peripheral blood mononuclear cells by real-time polymerase chain reaction. Interleukin-10 (IL-10) and hyaluronic acid (HA) levels were also assessed. All findings were correlated with disease activity, viral load and fibrogenesis. RESULTS: There was a significant decrease in co-stimulatory markers; CD83, CD86 and CD40 in groups 2 and 3 vs the control group. Co-stimulatory markers were significantly higher in group 3 vs group 2. There was a significant elevation in PD-L1 in both HCV groups vs the control group. PD-L1 was significantly lower in group 3 vs group 2. There was a significant elevation in IL-10 and HA levels in groups 2 and 3, where IL-10 was higher in group 3 and HA was lower in group 3 vs group 2. HA level was significantly correlated with disease activity and fibrosis grade in group 2. IL-10 was significantly correlated with fibrosis grade in group 2. There were significant negative correlations between co-stimulatory markers and viral load in groups 2 and 3, except CD83 in dialysis patients. There was a significant positive correlation between PD-L1 and viral load in both HCV groups. CONCLUSION: A significant decrease in DC co-stimulatory markers and a significant increase in a DC co-inhibitory marker were observed in HCV subjects and to a lesser extent in dialysis patients. PMID:24282359

  9. Inhibitory effect of corn silk on skin pigmentation.

    Science.gov (United States)

    Choi, Sang Yoon; Lee, Yeonmi; Kim, Sung Soo; Ju, Hyun Min; Baek, Ji Hwoon; Park, Chul-Soo; Lee, Dong-Hyuk

    2014-03-03

    In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

  10. Inhibitory Effect of Corn Silk on Skin Pigmentation

    Directory of Open Access Journals (Sweden)

    Sang Yoon Choi

    2014-03-01

    Full Text Available In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

  11. Phytochemical screening and in vitro acetylcholinesterase inhibitory ...

    African Journals Online (AJOL)

    Phytochemical screening and in vitro acetylcholinesterase inhibitory activity of seven plant extracts. Titilayo Johnson, Oduje A. Akinsanmi, Enoch J. Banbilbwa, Tijani A. Yahaya, Karima Abdulaziz, Kolade Omole ...

  12. Expression of macrophage migration inhibitory factor and CD74 in the inner ear and middle ear in lipopolysaccharide-induced otitis media.

    Science.gov (United States)

    Ishihara, Hisashi; Kariya, Shin; Okano, Mitsuhiro; Zhao, Pengfei; Maeda, Yukihide; Nishizaki, Kazunori

    2016-10-01

    Significant expression of macrophage migration inhibitory factor and its receptor (CD74) was observed in both the middle ear and inner ear in experimental otitis media in mice. Modulation of macrophage migration inhibitory factor and its signaling pathway might be useful in the management of inner ear inflammation due to otitis media. Inner ear dysfunction secondary to otitis media has been reported. However, the specific mechanisms involved are not clearly understood. The aim of this study is to investigate the expression of macrophage migration inhibitory factor and CD74 in the middle ear and inner ear in lipopolysaccharide-induced otitis media. BALB/c mice received a transtympanic injection of either lipopolysaccharide or phosphate-buffered saline (PBS). The mice were sacrificed 24 h after injection, and temporal bones were processed for polymerase chain reaction (PCR) analysis, histologic examination, and immunohistochemistry. PCR examination revealed that the lipopolysaccharide-injected mice showed a significant up-regulation of macrophage migration inhibitory factor in both the middle ear and inner ear as compared with the PBS-injected control mice. The immunohistochemical study showed positive reactions for macrophage migration inhibitory factor and CD74 in infiltrating inflammatory cells, middle ear mucosa, and inner ear in the lipopolysaccharide-injected mice.

  13. A virtual screening method for inhibitory peptides of Angiotensin I-converting enzyme.

    Science.gov (United States)

    Wu, Hongxi; Liu, Yalan; Guo, Mingrong; Xie, Jingli; Jiang, XiaMin

    2014-09-01

    Natural small peptides from foods have been proven to be efficient inhibitors of Angiotensin I-converting enzyme (ACE) for the regulation of blood pressure. The traditional ACE inhibitory peptides screening method is both time consuming and money costing, to the contrary, virtual screening method by computation can break these limitations. We establish a virtual screening method to obtain ACE inhibitory peptides with the help of Libdock module of Discovery Studio 3.5 software. A significant relationship between Libdock score and experimental IC(50) was found, Libdock score = 10.063 log(1/IC(50)) + 68.08 (R(2) = 0.62). The credibility of the relationship was confirmed by testing the coincidence of the estimated log(1/IC(50)) and measured log(1/IC(50)) (IC(50) is 50% inhibitory concentration toward ACE, in μmol/L) of 5 synthetic ACE inhibitory peptides, which was virtual hydrolyzed and screened from a kind of seafood, Phascolosoma esculenta. Accordingly, Libdock method is a valid IC(50) estimation tool and virtual screening method for small ACE inhibitory peptides. © 2014 Institute of Food Technologists®

  14. Inhibitory effects of furanocoumarin derivatives in Kampo extract medicines on P-glycoprotein at the blood-brain barrier.

    Science.gov (United States)

    Iwanaga, Kazunori; Yoneda, Shinji; Hamahata, Yukimi; Miyazaki, Makoto; Shibano, Makio; Taniguchi, Masahiko; Baba, Kimiye; Kakemi, Masawo

    2011-01-01

    Furanocoumarin derivatives, known as components of grapefruit juice, showing inhibitory effects against P-glycoprotein (P-gp) in the intestine are also contained in the plants of rutaceae and umbelliferae families, which are used as components of Kampo extract medicines. In this study, we investigated the inhibitory effects of byakangelicol and rivulobirin A, known as furanocoumarins showing P-gp inhibitory effect using Caco-2 monolayer, against P-gp at the blood-brain barrier (BBB) under both in vitro and in vivo conditions. First we studied the membrane permeability of furanocoumarins to clarify whether they can be absorbed from the intestine. Both furanocoumarins showed high permeability through the Caco-2 monolayer, suggesting that they can easily reach the systemic circulation after oral administration. Then, we evaluated the effect of these furanocoumarins on the uptake of calcein acetoxymethyl ester (calcein-AM), a P-gp substrate, into bovine brain microvascular endothelial cells (BBMEC). Both furanocoumarins significantly increased the uptake amount of calcein-AM into BBMEC by the inhibition of P-gp at the BBB in vitro. Next we also investigated the P-gp inhibitory effect of these furanocoumarins at the rat BBB in vivo using verapamil as a P-gp substrate. Both furanocoumarins increased the B/P ratio of verapamil compared to the control, even under in vivo conditions; however, the extent of the inhibitory effect was much lower than in vitro condition. In conclusion, byakangelicol and rivulobirin A may inhibit P-gp expressed at the BBB even under in vivo conditions. Further studies using Kampo extract medicines under in vivo condition are necessary for safe drug therapy.

  15. Optimization of inhibitory decision rules relative to length and coverage

    KAUST Repository

    Alsolami, Fawaz

    2012-01-01

    The paper is devoted to the study of algorithms for optimization of inhibitory rules relative to the length and coverage. In contrast with usual rules that have on the right-hand side a relation "attribute ≠ value", inhibitory rules have a relation "attribute = value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. © 2012 Springer-Verlag.

  16. Inhibitory Synaptic Plasticity - Spike timing dependence and putative network function.

    Directory of Open Access Journals (Sweden)

    Tim P Vogels

    2013-07-01

    Full Text Available While the plasticity of excitatory synaptic connections in the brain has been widely studied, the plasticity of inhibitory connections is much less understood. Here, we present recent experimental and theoretical □ndings concerning the rules of spike timing-dependent inhibitory plasticity and their putative network function. This is a summary of a workshop at the COSYNE conference 2012.

  17. Modifying yeast tolerance to inhibitory conditions of ethanol production processes

    Directory of Open Access Journals (Sweden)

    Luis eCaspeta

    2015-11-01

    Full Text Available Saccharomyces cerevisiae strains having a broad range of substrate utilization, rapid substrate consumption and conversion to ethanol, as well as good tolerance to inhibitory conditions are ideal for cost-competitive ethanol production from lignocellulose. A major drawback to directly design S. cerevisiae tolerance to inhibitory conditions of lignocellulosic ethanol production processes is the lack of knowledge about basic aspects of its cellular signaling network in response to stress. Here we highlight the inhibitory conditions found in ethanol production processes, the targeted cellular functions, the key contributions of integrated –omics analysis to reveal cellular stress responses according to these inhibitors, and current status on design-based engineering of tolerant and efficient S. cerevisiae strains for ethanol production from lignocellulose.

  18. Inhibitory effect of three C-glycosylflavonoids from Cymbopogon citratus (Lemongrass) on human low density lipoprotein oxidation.

    Science.gov (United States)

    Orrego, Roxana; Leiva, Elba; Cheel, José

    2009-09-30

    This study assessed the inhibitory effect of three C-glycosylflavonoids from Cymbopogon citratus leaves--isoorientin (1), swertiajaponin (2) and isoorientin 2"-Orhamnoside (3)--on human LDL oxidation. Isolated LDL was incubated with compounds 1-3 and the kinetics of lipid peroxidation were assessed by conjugated diene and malondialdehyde-thiobarbituric acid reactive substances (MDA-TBARS) formation after addition of copper ions. Significant differences (p < 0.05) between the lag time phase of the control and the lag time phase in the presence of the compounds 1 (0.25 microM) and 2 (0.50 microM) were observed. After five hours of incubation all three compounds showed a significant inhibitory effect on MDA-TBARS formation with respect to the control. After six hours of incubation only compound 1 kept a remarkable antioxidant effect. This study demonstrates that isoorientin (1) is an effective inhibitor of in vitro LDL oxidation. As oxidative damage to LDL is a key event in the formation of atherosclerotic lesions, the use of this natural antioxidant may be beneficial to prevent or attenuate atherosclerosis.

  19. Inhibitory serum factor of lymphoproliferative response to allogeneic cells in pregnancy

    Directory of Open Access Journals (Sweden)

    Silvia Daher

    Full Text Available INTRODUCTION: An inhibitory serum factor of mixed lymphocyte culture (MLC has been associated with successful pregnancy after lymphocyte transfusion in women with unexplained recurrent spontaneous abortions (RSA. OBJECTIVE: Investigate whether the inhibitory serum factor of MLC is essential for a successful pregnancy. METHOD: Sera from 33 healthy pregnant women and from 40 women with RSA were assessed by a one-way MLC in which the woman's lymphocytes were stimulated with her partner's lymphocytes or with third party lymphocytes. RESULTS: An inhibitory serum effect (inhibition > 50% as compared to normal serum was detected in 45% of the pregnant women who had at least 1 previous parity, in 8% of the primigravidea, in 29% of those with one abortion and in 58% of those with more than one abortion. CONCLUSION: MLC inhibitory serum factor does not seem to be an essential factor for pregnancy development. Therefore, it should not be considered as a parameter for the assessment of RSA patients.

  20. Inhibitory Effects of Urginea maritima (L. Baker, Zhumeria majdae Rech. F. and Wendelbo and Physalis divaricata D. Don Ethanolic Extracts on Mushroom Tyrosinase

    Directory of Open Access Journals (Sweden)

    Foroogh Namjoyan, Alireza Jahangiri, Mohammad Ebrahim Azemi, Hamideh Mousavi

    2016-06-01

    Full Text Available Background: Tyrosinase is a key enzyme in melanin synthesis from tyrosine. To prevent or treat pigmentation disorders, tyrosinase inhibitors have been used increasingly for medicinal and cosmetic products. The aim of this study is to evaluate inhibitory effects of Urginea maritima (L. Baker, Zhumeria majdae Rech.f. & Wendelbo and Physalis divaricata D.Don on mushroom tyrosinase. Methods: The inhibitory activities of the hydroalcoholic extracts of plants against oxidation of L-DOPA (as a substrate by mushroom tyrosinase were investigated. The amount of formed DOPAchrome was determined at 475 nm as optical density. Results: The extracts showed anti-tyrosinase activity weaker than positive control (Kojic acid. The inhibitory activity of tested plants: U.maritima, Z.majdae and P.divaricata against mushroom tyrosinase were 38.61, 29.70 and 25.74 % at 1.67 mg/mL, respectively. Conclusion: The most tyrosinase inhibitory activity was seen for U.maritima. However more investigations on human tyrosinase, toxicological and clinical studies are needed to confirm its activity.

  1. Inhibitory effects of crude extracts from several plants on postharvest pathogens of citrus

    Science.gov (United States)

    Gong, Mingfu; Guan, Qinlan; Xu, Shanshan

    2018-04-01

    China is one of the most important origin of citrus. Enormous economic losses was caused by fungal diseases in citrus harvest storage every year. The effective antimicrobial substances of garlic, ginger, celery and pepper were extracted by ethanol extraction and water extraction respectively. The inhibitory effects of the crude extract on Penicillium sp. caused fungal diseases in citrus harvest storage were also determined. The results showed that the extracts of garlic, ginger and celery had inhibitory effect on P. sp., but the extracts of pepper had no inhibitory effect on P. sp.. The garlic ethanol extracts had the best inhibitory effect on P. citrinum.

  2. Differential Receptive Field Properties of Parvalbumin and Somatostatin Inhibitory Neurons in Mouse Auditory Cortex.

    Science.gov (United States)

    Li, Ling-Yun; Xiong, Xiaorui R; Ibrahim, Leena A; Yuan, Wei; Tao, Huizhong W; Zhang, Li I

    2015-07-01

    Cortical inhibitory circuits play important roles in shaping sensory processing. In auditory cortex, however, functional properties of genetically identified inhibitory neurons are poorly characterized. By two-photon imaging-guided recordings, we specifically targeted 2 major types of cortical inhibitory neuron, parvalbumin (PV) and somatostatin (SOM) expressing neurons, in superficial layers of mouse auditory cortex. We found that PV cells exhibited broader tonal receptive fields with lower intensity thresholds and stronger tone-evoked spike responses compared with SOM neurons. The latter exhibited similar frequency selectivity as excitatory neurons. The broader/weaker frequency tuning of PV neurons was attributed to a broader range of synaptic inputs and stronger subthreshold responses elicited, which resulted in a higher efficiency in the conversion of input to output. In addition, onsets of both the input and spike responses of SOM neurons were significantly delayed compared with PV and excitatory cells. Our results suggest that PV and SOM neurons engage in auditory cortical circuits in different manners: while PV neurons may provide broadly tuned feedforward inhibition for a rapid control of ascending inputs to excitatory neurons, the delayed and more selective inhibition from SOM neurons may provide a specific modulation of feedback inputs on their distal dendrites. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Humoral Na+-K+ pump inhibitory activity in essential hypertension and in normotensive subjects after acute volume expansion

    International Nuclear Information System (INIS)

    Pamnani, M.B.; Burris, J.F.; Jemionek, J.F.; Huot, S.J.; Price, M.; Freis, E.D.; Haddy, F.J.

    1989-01-01

    Plasma from black male patients with essential hypertension was bioassayed for vascular Na+-K+ pump inhibitory activity. Halves of the same rat tail artery were incubated for two hours in boiled plasma supernates from a hypertensive patient and a paired age-, sex-, and race-matched normotensive subject and then ouabain-sensitive 86 Rb uptake was measured. Ouabain-sensitive 86 Rb uptake by their leukocytes was also measured. Eighteen pairs of subjects were studied. The uptakes were not significantly different in the hypertensive patients and control subjects. However, when we selected from the eighteen hypertensive patients, nine with low plasma renin activity on the day of the study, uptakes were reduced in the hypertensive patients relative to the paired control subjects. We also assayed plasma supernates from normotensive black and white male subjects before and after acute volume expansion (2.5 L saline IV + 1.5 L distilled water orally over a three-hour period) and from paired normotensive subjects before and after sham volume expansion and obtained a positive bioassay in the expanded subjects both on intraindividual and interindividual comparisons. These studies demonstrate increased vascular Na+-K+ pump inhibitory activity in the plasma of black male patients with low renin essential hypertension and in the plasma of normotensive subjects after acute volume expansion. The findings suggest that the inhibitory activity in the hypertensive subjects' plasma is related to volume expansion, relative or absolute

  4. Shifting brain inhibitory balance and connectivity of the prefrontal cortex of adults with autism spectrum disorder.

    Science.gov (United States)

    Ajram, L A; Horder, J; Mendez, M A; Galanopoulos, A; Brennan, L P; Wichers, R H; Robertson, D M; Murphy, C M; Zinkstok, J; Ivin, G; Heasman, M; Meek, D; Tricklebank, M D; Barker, G J; Lythgoe, D J; Edden, R A E; Williams, S C; Murphy, D G M; McAlonan, G M

    2017-05-23

    Currently, there are no effective pharmacologic treatments for the core symptoms of autism spectrum disorder (ASD). There is, nevertheless, potential for progress. For example, recent evidence suggests that the excitatory (E) glutamate and inhibitory (I) GABA systems may be altered in ASD. However, no prior studies of ASD have examined the 'responsivity' of the E-I system to pharmacologic challenge; or whether E-I modulation alters abnormalities in functional connectivity of brain regions implicated in the disorder. Therefore, we used magnetic resonance spectroscopy ([1H]MRS) to measure prefrontal E-I flux in response to the glutamate and GABA acting drug riluzole in adult men with and without ASD. We compared the change in prefrontal 'Inhibitory Index'-the GABA fraction within the pool of glutamate plus GABA metabolites-post riluzole challenge; and the impact of riluzole on differences in resting-state functional connectivity. Despite no baseline differences in E-I balance, there was a significant group difference in response to pharmacologic challenge. Riluzole increased the prefrontal cortex inhibitory index in ASD but decreased it in controls. There was also a significant group difference in prefrontal functional connectivity at baseline, which was abolished by riluzole within the ASD group. Our results also show, for we believe the first time in ASD, that E-I flux can be 'shifted' with a pharmacologic challenge, but that responsivity is significantly different from controls. Further, our initial evidence suggests that abnormalities in functional connectivity can be 'normalised' by targeting E-I, even in adults.

  5. NK cell activation: distinct stimulatory pathways counterbalancing inhibitory signals.

    Science.gov (United States)

    Bakker, A B; Wu, J; Phillips, J H; Lanier, L L

    2000-01-01

    A delicate balance between positive and negative signals regulates NK cell effector function. Activation of NK cells may be initiated by the triggering of multiple adhesion or costimulatory molecules, and can be counterbalanced by inhibitory signals induced by receptors for MHC class I. A common pathway of inhibitory signaling is provided by immunoreceptor tyrosine-based inhibitory motifs (ITIMs) in the cytoplasmic domains of these receptors which mediate the recruitment of SH2 domain-bearing tyrosine phosphate-1 (SHP-1). In contrast to the extensive progress that has been made regarding the negative regulation of NK cell function, our knowledge of the signals that activate NK cells is still poor. Recent studies of the activating receptor complexes have shed new light on the induction of NK cell effector function. Several NK receptors using novel adaptors with immunoreceptor tyrosine-based activation motifs (ITAMs) and with PI 3-kinase recruiting motifs have been implicated in NK cell stimulation.

  6. On minimal inhibitory rules for almost all k-valued information systems

    KAUST Repository

    Moshkov, Mikhail

    2009-07-30

    The minimal inhibitory rules for information systems can be used for construction of classifiers. We show that almost all information systems from a certain large class of information systems have relatively short minimal inhibitory rules. However, the number of such rules is not polynomial in the number of attributes and the number of objects. This class consists of all k-valued information systems, k ≥ 2, with the number of objects polynomial in the number of attributes. Hence, for efficient construction of classifiers some filtration techniques in rule generation are necessary. Another way is to work with lazy classification algorithms based on inhibitory rules.

  7. Confirmation of association of the macrophage migration inhibitory factor gene with systemic sclerosis in a large European population

    NARCIS (Netherlands)

    Bossini-Castillo, L.; Simeon, C.P.; Beretta, L.; Vonk, M.C.; Callejas-Rubio, J.L.; Espinosa, G.; Carreira, P.; Camps, M.T.; Rodriguez-Rodriguez, L.; Rodriguez-Carballeira, M.; Garcia-Hernandez, F.J.; Lopez-Longo, F.J.; Hernandez-Hernandez, V.; Saez-Comet, L.; Egurbide, M.V.; Hesselstrand, R.; Nordin, A.; Hoffmann-Vold, A.M.; Vanthuyne, M.; Smith, V.; Langhe, E. De; Kreuter, A.; Riemekasten, G.; Witte, T.J.M. de; Hunzelmann, N.; Voskuyl, A.E.; Schuerwegh, A.J.; Lunardi, C.; Airo, P.; Scorza, R.; Shiels, P.; Laar, J.M. van; Fonseca, C.; Denton, C.; Herrick, A.; Worthington, J.; Koeleman, B.P.; Rueda, B.; Radstake, T.R.D.J.; Martin, J.

    2011-01-01

    Objectives. The aim of this study was to confirm the implication of macrophage migration inhibitory factor (MIF) gene in SSc susceptibility or clinical phenotypes in a large European population. Methods. A total of 3800 SSc patients and 4282 healthy controls of white Caucasian ancestry from eight

  8. Fungal growth inhibitory properties of new phytosphingolipid analogues.

    Science.gov (United States)

    Mormeneo, D; Manresa, A; Casas, J; Llebaria, A; Delgado, A

    2008-04-01

    To study the growth inhibitory properties of a series of phytosphingosine (PHS) and phytoceramide (PHC) analogues. A panel of two yeast (Candida albicans and Saccharomyces cerevisiae) and six moulds (Aspergillus repens, Aspergillus niger, Penicillium chrysogenum, Cladosporium cladosporioides, Arthroderma uncinatum and Penicillium funiculosum) has been used in this study. A series of new PHS and PHC analogues differing at the sphingoid backbone and the functional group at C1 position were synthesized. Among PHS analogues, 1-azido derivative 1c, bearing the natural D-ribo stereochemistry, showed a promising growth inhibitory profile. Among PHC analogues, compound 12, with a bulky N-pivaloyl group and a Z double bond at C3 position of the sphingoid chain, was the most active growth inhibitor. Minimal inhibitory concentration values were in the range of 23-48 micromol l(-1) for 1c and 44-87 micromol l(-1) for 12. Only scattered data on the antifungal activity of phytosphingolipids have been reported in the literature. This is the first time that a series of analogues of this kind are tested and compared to discern their structural requirements for antifungal activity.

  9. Increased beta rhythm as an indicator of inhibitory mechanisms in tourette syndrome

    DEFF Research Database (Denmark)

    Niccolai, Valentina; van Dijk, Hanneke; Franzkowiak, Stephanie

    2016-01-01

    BACKGROUND: Inhibitory oscillatory mechanisms subserving tic compensation have been put forward in Tourette syndrome. Modulation of the beta rhythm (15-25 Hz) as the well-established oscillatory movement execution-inhibition indicator was tested during a cognitive-motor task in patients with Tour......BACKGROUND: Inhibitory oscillatory mechanisms subserving tic compensation have been put forward in Tourette syndrome. Modulation of the beta rhythm (15-25 Hz) as the well-established oscillatory movement execution-inhibition indicator was tested during a cognitive-motor task in patients...... in parieto-occipital brain regions contralaterally to the response hand. Average beta power and power gain correlated negatively with tic severity. CONCLUSIONS: Increased motor inhibitory as well as visuomotor attentional processes are likely to subserve tic compensation. Correlational results suggest...... that stronger inhibitory compensation accompanies less tic severity. © 2016 International Parkinson and Movement Disorder Society....

  10. In vitro evaluation of capsaicin inhibitory effects on zonula occludens toxin in vibrio cholerae ATCC14035 strain

    Directory of Open Access Journals (Sweden)

    Soroor Erfanimanesh

    2014-10-01

    Conclusion: Capsaicin is one of the active compounds of red chili that can drastically suppress zot gene expression and shows promising inhibitory effect against V. cholerae zot production. Thus, routine intake of red chilli, which is easily available and inexpensive, may be an alternative approach to prevent and control symptoms of cholera.

  11. Growth inhibition of Listeria spp. on Camembert cheese by bacteria producing inhibitory substances.

    Science.gov (United States)

    Sulzer, G; Busse, M

    1991-12-01

    Bacterial strains exhibiting antimicrobial activity towards other bacteria are quite common in nature. During the past few years several genera have been shown to exert inhibitory action against Listeria. spp. In the present work strains of Enterococcus, Lactobacillus and Lactococcus were tested for their influence on the development of Listeria spp. on Camembert cheese. Partial or complete inhibition of growth of Listeria spp. was observed using various inhibitory bacteria. Complete inhibition occurred when the inhibitory strain was used as a starter culture and there was a low level of contamination with Listeria spp. during the first stage of ripening. Very little inhibition occurred if the inhibitory strain was added together with the starter culture.

  12. Mechanism underlying unaltered cortical inhibitory synaptic transmission in contrast with enhanced excitatory transmission in CaV2.1 knockin migraine mice

    Science.gov (United States)

    Vecchia, Dania; Tottene, Angelita; van den Maagdenberg, Arn M.J.M.; Pietrobon, Daniela

    2014-01-01

    Familial hemiplegic migraine type 1 (FHM1), a monogenic subtype of migraine with aura, is caused by gain-of-function mutations in CaV2.1 (P/Q-type) calcium channels. In FHM1 knockin mice, excitatory neurotransmission at cortical pyramidal cell synapses is enhanced, but inhibitory neurotransmission at connected pairs of fast-spiking (FS) interneurons and pyramidal cells is unaltered, despite being initiated by CaV2.1 channels. The mechanism underlying the unaltered GABA release at cortical FS interneuron synapses remains unknown. Here, we show that the FHM1 R192Q mutation does not affect inhibitory transmission at autapses of cortical FS and other types of multipolar interneurons in microculture from R192Q knockin mice, and investigate the underlying mechanism. Lowering the extracellular [Ca2+] did not reveal gain-of-function of evoked transmission neither in control nor after prolongation of the action potential (AP) with tetraethylammonium, indicating unaltered AP-evoked presynaptic calcium influx at inhibitory autapses in FHM1 KI mice. Neither saturation of the presynaptic calcium sensor nor short duration of the AP can explain the unaltered inhibitory transmission in the mutant mice. Recordings of the P/Q-type calcium current in multipolar interneurons in microculture revealed that the current density and the gating properties of the CaV2.1 channels expressed in these interneurons are barely affected by the FHM1 mutation, in contrast with the enhanced current density and left-shifted activation gating of mutant CaV2.1 channels in cortical pyramidal cells. Our findings suggest that expression of specific CaV2.1 channels differentially sensitive to modulation by FHM1 mutations in inhibitory and excitatory cortical neurons underlies the gain-of-function of excitatory but unaltered inhibitory synaptic transmission and the likely consequent dysregulation of the cortical excitatory–inhibitory balance in FHM1. PMID:24907493

  13. Why (and how) should we study the interplay between emotional arousal, Theory of Mind, and inhibitory control to understand moral cognition?

    Science.gov (United States)

    Buon, Marine; Seara-Cardoso, Ana; Viding, Essi

    2016-12-01

    Findings in the field of experimental psychology and cognitive neuroscience have shed new light on our understanding of the psychological and biological bases of morality. Although a lot of attention has been devoted to understanding the processes that underlie complex moral dilemmas, attempts to represent the way in which individuals generate moral judgments when processing basic harmful actions are rare. Here, we will outline a model of morality which proposes that the evaluation of basic harmful actions relies on complex interactions between emotional arousal, Theory of Mind (ToM) capacities, and inhibitory control resources. This model makes clear predictions regarding the cognitive processes underlying the development of and ability to generate moral judgments. We draw on data from developmental and cognitive psychology, cognitive neuroscience, and psychopathology research to evaluate the model and propose several conceptual and methodological improvements that are needed to further advance our understanding of moral cognition and its development.

  14. Characterisation of inhibitory substances produced by two Pseudoalteromonas species and the cyanobacterial strain Flo1

    OpenAIRE

    Rau, Jan Erik

    2011-01-01

    In the present study the inhibitory substances of P. aurantia NCIMB 2052T and P. citrea NCIMB 1889T were investigated with respect to their substantial and functional nature, their inhibitory potential, their stability against various treatments as well as the growth phases and incubation conditions when the substances are produced. In addition, an inhibitory substance produced by strain Flo1 was examined regarding its structure, function, and inhibitory potential. Furthermore, its taxonomic ...

  15. Sleep: The hebbian reinforcement of the local inhibitory synapses.

    Science.gov (United States)

    Touzet, Claude

    2015-09-01

    Sleep is ubiquitous among the animal realm, and represents about 30% of our lives. Despite numerous efforts, the reason behind our need for sleep is still unknown. The Theory of neuronal Cognition (TnC) proposes that sleep is the period of time during which the local inhibitory synapses (in particular the cortical ones) are replenished. Indeed, as long as the active brain stays awake, hebbian learning guarantees that efficient inhibitory synapses lose their efficiency – just because they are efficient at avoiding the activation of the targeted neurons. Since hebbian learning is the only known mechanism of synapse modification, it follows that to replenish the inhibitory synapses' efficiency, source and targeted neurons must be activated together. This is achieved by a local depolarization that may travel (wave). The period of time during which such slow waves are experienced has been named the "slow-wave sleep" (SWS). It is cut into several pieces by shorter periods of paradoxical sleep (REM) which activity resembles that of the awake state. Indeed, SWS – because it only allows local neural activation – decreases the excitatory long distance connections strength. To avoid losing the associations built during the awake state, these long distance activations are played again during the REM sleep. REM and SWS sleeps act together to guarantee that when the subject awakes again, his inhibitory synaptic efficiency is restored and his (excitatory) long distance associations are still there. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Inhibitory coherence in a heterogeneous population of subthreshold and suprathreshold type-I neurons

    International Nuclear Information System (INIS)

    Kim, Sang-Yoon; Hong, Duk-Geun; Kim, Jean; Lim, Woochang

    2012-01-01

    We study inhibitory coherence (i.e. collective coherence by synaptic inhibition) in a population of globally coupled type-I neurons, which can fire at arbitrarily low frequency. No inhibitory coherence is observed in a homogeneous population composed of only subthreshold neurons, which exhibit noise-induced firings. In addition to subthreshold neurons, there exist spontaneously firing suprathreshold neurons in a noisy environment of a real brain. To take into consideration the effect of suprathreshold neurons on inhibitory coherence, we consider a heterogeneous population of subthreshold and suprathreshold neurons and investigate the inhibitory coherence by increasing the fraction of suprathreshold neurons P supra . As P supra passes a threshold P* supra , suprathreshold neurons begin to synchronize and play the role of coherent inhibitors for the emergence of inhibitory coherence. Thus, regularly oscillating population-averaged global potential appears for P supra > P* supra . For this coherent case, suprathreshold neurons exhibit sparse spike synchronization (i.e. individual potentials of suprathreshold neurons consist of coherent sparse spikings and coherent subthreshold small-amplitude hoppings). By virtue of their coherent inhibition, sparsely synchronized suprathreshold neurons suppress the noisy activity of subthreshold neurons. Thus, subthreshold neurons exhibit hopping synchronization (i.e. only coherent subthreshold hopping oscillations without spikings appear in the individual potentials of subthreshold neurons). We also characterize the inhibitory coherence in terms of the ‘statistical-mechanical’ spike-based and correlation-based measures, which quantify the average contributions of the microscopic individual spikes and individual potentials to the macroscopic global potential. Finally, the effect of sparse randomness of synaptic connectivity on the inhibitory coherence is briefly discussed. (paper)

  17. Inhibition of NKCC1 attenuated hippocampal LTP formation and inhibitory avoidance in rat.

    Directory of Open Access Journals (Sweden)

    Meng Chang Ko

    Full Text Available The loop diuretic bumetanide (Bumex is thought to have antiepileptic properties via modulate GABAA mediated signaling through their antagonism of cation-chloride cotransporters. Given that loop diuretics may act as antiepileptic drugs that modulate GABAergic signaling, we sought to investigate whether they also affect hippocampal function. The current study was performed to evaluate the possible role of NKCC1 on the hippocampal function. Brain slice extracellular recording, inhibitory avoidance, and western blot were applied in this study. Results showed that hippocampal Long-term potentiation was attenuated by suprafusion of NKCC1 inhibitor bumetanide, in a dose dependent manner. Sequent experiment result showed that Intravenous injection of bumetanide (15.2 mg/kg 30 min prior to the training session blocked inhibitory avoidance learning significantly. Subsequent control experiment's results excluded the possible non-specific effect of bumetanide on avoidance learning. We also found the phosphorylation of hippocampal MAPK was attenuated after bumetanide administration. These results suggested that hippocampal NKCC1 may via MAPK signaling cascade to possess its function.

  18. LTS and FS inhibitory interneurons, short-term synaptic plasticity, and cortical circuit dynamics.

    Directory of Open Access Journals (Sweden)

    Itai Hayut

    2011-10-01

    Full Text Available Somatostatin-expressing, low threshold-spiking (LTS cells and fast-spiking (FS cells are two common subtypes of inhibitory neocortical interneuron. Excitatory synapses from regular-spiking (RS pyramidal neurons to LTS cells strongly facilitate when activated repetitively, whereas RS-to-FS synapses depress. This suggests that LTS neurons may be especially relevant at high rate regimes and protect cortical circuits against over-excitation and seizures. However, the inhibitory synapses from LTS cells usually depress, which may reduce their effectiveness at high rates. We ask: by which mechanisms and at what firing rates do LTS neurons control the activity of cortical circuits responding to thalamic input, and how is control by LTS neurons different from that of FS neurons? We study rate models of circuits that include RS cells and LTS and FS inhibitory cells with short-term synaptic plasticity. LTS neurons shift the RS firing-rate vs. current curve to the right at high rates and reduce its slope at low rates; the LTS effect is delayed and prolonged. FS neurons always shift the curve to the right and affect RS firing transiently. In an RS-LTS-FS network, FS neurons reach a quiescent state if they receive weak input, LTS neurons are quiescent if RS neurons receive weak input, and both FS and RS populations are active if they both receive large inputs. In general, FS neurons tend to follow the spiking of RS neurons much more closely than LTS neurons. A novel type of facilitation-induced slow oscillations is observed above the LTS firing threshold with a frequency determined by the time scale of recovery from facilitation. To conclude, contrary to earlier proposals, LTS neurons affect the transient and steady state responses of cortical circuits over a range of firing rates, not only during the high rate regime; LTS neurons protect against over-activation about as well as FS neurons.

  19. Characterization of a translation inhibitory protein from Luffa aegyptiaca.

    Science.gov (United States)

    Ramakrishnan, S; Enghlid, J J; Bryant, H L; Xu, F J

    1989-04-28

    A protein with a molecular weight of about 30,000 was purified from the seeds of Luffa aegyptiaca. This protein inhibited cell free translation at pM concentrations. In spite of functional similarity to other ribosomal inhibitory proteins, the NH2-terminal analysis did not show any significant homology. Competitive inhibition studies indicate no immunological crossreactivity between the inhibitory protein from Luffa aegyptiaca, pokeweed antiviral protein (PAP) and recombinant ricin A chain. Chemical linkage of the protein to a monoclonal antibody reactive to transferrin receptor resulted in a highly cytotoxic conjugate.

  20. Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

    International Nuclear Information System (INIS)

    Murata, Hajime; Iio, Masahiro; Yamada, Hideo; Chiba, Kazuo; Kobayashi, Masayoshi.

    1975-01-01

    To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10 -3 μg/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO 4 -, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 67 Ga-citrate and 57 Co-bleomycin as they were supplied. 111 In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, 131 I-PVP, 59 FeCl 3 , Na-phosphate ( 32 P), 198 Au-colloid and 75 Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used 169 Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10 -3 μg/ml due to addition of a small amount of benzyl alcohol. 131 I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 198 Au-colloid, 57 Co-bleomycin and 75 Se-selenomethionine. (auth.)

  1. Inhibitory neurotransmission and olfactory memory in honeybees.

    Science.gov (United States)

    El Hassani, Abdessalam Kacimi; Giurfa, Martin; Gauthier, Monique; Armengaud, Catherine

    2008-11-01

    In insects, gamma-aminobutyric acid (GABA) and glutamate mediate fast inhibitory neurotransmission through ligand-gated chloride channel receptors. Both GABA and glutamate have been identified in the olfactory circuit of the honeybee. Here we investigated the role of inhibitory transmission mediated by GABA and glutamate-gated chloride channels (GluCls) in olfactory learning and memory in honeybees. We combined olfactory conditioning with injection of ivermectin, an agonist of GluCl receptors. We also injected a blocker of glutamate transporters (L-trans-PDC) or a GABA analog (TACA). We measured acquisition and retention 1, 24 and 48 h after the last acquisition trial. A low dose of ivermectin (0.01 ng/bee) impaired long-term olfactory memory (48 h) while a higher dose (0.05 ng/bee) had no effect. Double injections of ivermectin and L-trans-PDC or TACA had different effects on memory retention, depending on the doses and agents combined. When the low dose of ivermectin was injected after Ringer, long-term memory was again impaired (48 h). Such an effect was rescued by injection of both TACA and L-trans-PDC. A combination of the higher dose of ivermectin and TACA decreased retention at 48 h. We interpret these results as reflecting the involvement of both GluCl and GABA receptors in the impairment of olfactory long-term memory induced by ivermectin. These results illustrate the diversity of inhibitory transmission and its implication in long-term olfactory memory in honeybees.

  2. Influence of baking enzymes on antimicrobial activity of five bacteriocin-like inhibitory substances produced by lactic acid bacteria isolated from Lithuanian sourdoughs.

    Science.gov (United States)

    Narbutaite, V; Fernandez, A; Horn, N; Juodeikiene, G; Narbad, A

    2008-12-01

    To evaluate the effect of four different baking enzymes on the inhibitory activity of five bacteriocin-like inhibitory substances (BLIS) produced by lactic acid bacteria (LAB) isolated from Lithuanian sourdoughs. The overlay assay and the Bioscreen methods revealed that the five BLIS exhibited an inhibitory effect against spore germination and vegetative outgrowth of Bacillus subtilis, the predominant species causing ropiness in bread. The possibility that the observed antibacterial activity of BLIS might be lost after treatment with enzymes used for baking purposes was also examined. The enzymes tested; hemicellulase, lipase, amyloglucosidase and amylase had little or no effect on the majority of the antimicrobial activities associated with the five BLIS studied. This study suggests a potential application in the sourdough baking industry for these antimicrobial producing LAB strains in the control of B. subtilis spore germination and vegetative outgrowth.

  3. Inhibitory rTMS applied on somatosensory cortex in Wilson's disease patients with hand dystonia.

    Science.gov (United States)

    Lozeron, Pierre; Poujois, Aurélia; Meppiel, Elodie; Masmoudi, Sana; Magnan, Thierry Peron; Vicaut, Eric; Houdart, Emmanuel; Guichard, Jean-Pierre; Trocello, Jean-Marc; Woimant, France; Kubis, Nathalie

    2017-10-01

    Hand dystonia is a common complication of Wilson's disease (WD), responsible for handwriting difficulties and disability. Alteration of sensorimotor integration and overactivity of the somatosensory cortex have been demonstrated in dystonia. This study investigated the immediate after effect of an inhibitory repetitive transcranial magnetic stimulation (rTMS) applied over the somatosensory cortex on the writing function in WD patients with hand dystonia. We performed a pilot prospective randomized double-blind sham-controlled crossover rTMS study. A 20-min 1-Hz rTMS session, stereotaxically guided, was applied over the left somatosensory cortex in 13 WD patients with right dystonic writer's cramp. After 3 days, each patient was crossed-over to the alternative treatment. Patients were clinically evaluated before and immediately after each rTMS session with the Unified Wilson's Disease rating scale (UWDRS), the Writers' Cramp Rating Scale (WCRS), a specifically designed scale for handwriting difficulties in Wilson's disease patients (FAR, flow, accuracy, and rhythmicity evaluation), and a visual analog scale (VAS) for handwriting discomfort. No significant change in UWDRS, WCRS, VAS, or FAR scores was observed in patients treated with somatosensory inhibitory rTMS compared to the sham protocol. The FAR negatively correlated with UWDRS (r = -0.6; P = 0.02), but not with the WCRS score, disease duration, MRI diffusion lesions, or with atrophy scores. In our experimental conditions, a single inhibitory rTMS session applied over somatosensory cortex did not improve dystonic writer cramp in WD patients.

  4. Inhibitory effects of 3-bromopyruvate on human gastric cancer implant tumors in nude mice.

    Science.gov (United States)

    Xian, Shu-Lin; Cao, Wei; Zhang, Xiao-Dong; Lu, Yun-Fei

    2014-01-01

    Gastric cancer is a common malignant tumor. Our previous study demonstrated inhibitory effects of 3-bromopyruvate (3-BrPA) on pleural mesothelioma. Moreover, we found that 3-BrPA could inhibit human gastric cancer cell line SGC-7901 proliferation in vitro, but whether similar effects might be exerted in vivo have remained unclear. To investigate the effect of 3-BrPA to human gastric cancer implant tumors in nude mice. Animals were randomly divided into 6 groups: 3-BrPA low, medium and high dose groups, PBS negative control group 1 (PH7.4), control group 2 (PH 6.8-7.8) and positive control group receiving 5-FU. The TUNEL method was used to detect apoptosis, and cell morphology and structural changes of tumor tissue were observed under transmission electron microscopy (TEM). 3-BrPA low, medium, high dose group, and 5-FU group, the tumor volume inhibition rates were 34.5%, 40.2%, 45.1%, 47.3%, tumor volume of experimental group compared with 2 PBS groups (p0.05). TEM showed typical characteristics of apoptosis. TUNEL demonstrated apoptosis indices of 28.7%, 39.7%, 48.7% for the 3-BrPA low, medium, high dose groups, 42.2% for the 5-FU group and 5% and 4.3% for the PBS1 (PH7.4) and PBS2 (PH6.8-7.8) groups. Compared each experimental group with 2 negative control groups, there was significant difference (p0.05), but there was between the 5-FU and high dose groups (p<0.05). This study indicated that 3-BrPA in vivo has strong inhibitory effects on human gastric cancer implant tumors in nude mice .

  5. Hypotensive and Angiotensin-Converting Enzyme Inhibitory Activities of Eisenia fetida Extract in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Shumei Mao

    2015-01-01

    Full Text Available Objectives. This study aimed to investigate the antihypertensive effects of an Eisenia fetida extract (EFE and its possible mechanisms in spontaneously hypertensive rats (SHR rats. Methods. Sixteen-week-old SHR rats and Wistar-Kyoto rats (WKY rats were used in this study. Rats were, respectively, given EFE (EFE group, captopril (captopril group, or phosphate-buffered saline (PBS (normal control group and SHR group for 4 weeks. ACE inhibitory activity of EFE in vitro was determined. The systolic blood pressure (SBP and diastolic blood pressure (DBP were measured using a Rat Tail-Cuff Blood Pressure System. Levels of angiotensin II (Ang II, aldosterone (Ald, and 6-keto-prostaglandin F1 alpha (6-keto-PGF1α in plasma were determined by radioimmunoassay, and serum nitric oxide (NO concentration was measured by Griess reagent systems. Results. EFE had marked ACE inhibitory activity in vitro (IC50 = 2.5 mg/mL. After the 4-week drug management, SHR rats in EFE group and in captopril group had lower SBP and DBP, lower levels of Ang II and Ald, and higher levels of 6-keto-PGF1α and NO than the SHR rats in SHR group. Conclusion. These results indicate that EFE has hypotensive effects in SHR rats and its effects might be associated with its ACE inhibitory activity.

  6. High body mass index is associated with impaired cognitive control.

    Science.gov (United States)

    Sellaro, Roberta; Colzato, Lorenza S

    2017-06-01

    The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI) is associated with frontal lobe dysfunction and cognitive deficits concerning mental flexibility and inhibitory control efficiency. The present study aims at replicating and extending these observations. We compared cognitive control performance of normal weight (BMI task tapping either inhibitory control (Experiment 1) or interference control (Experiment 2). Experiment 1 replicated previous findings that found less efficient inhibitory control in overweight individuals. Experiment 2 complemented these findings by showing that cognitive control impairments associated with high BMI also extend to the ability to resolve stimulus-induced response conflict and to engage in conflict-driven control adaptation. The present results are consistent with and extend previous literature showing that high BMI in young, otherwise healthy individuals is associated with less efficient cognitive control functioning. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Dynamics of excitatory and inhibitory networks are differentially altered by selective attention

    Science.gov (United States)

    Snyder, Adam C.; Morais, Michael J.

    2016-01-01

    Inhibition and excitation form two fundamental modes of neuronal interaction, yet we understand relatively little about their distinct roles in service of perceptual and cognitive processes. We developed a multidimensional waveform analysis to identify fast-spiking (putative inhibitory) and regular-spiking (putative excitatory) neurons in vivo and used this method to analyze how attention affects these two cell classes in visual area V4 of the extrastriate cortex of rhesus macaques. We found that putative inhibitory neurons had both greater increases in firing rate and decreases in correlated variability with attention compared with putative excitatory neurons. Moreover, the time course of attention effects for putative inhibitory neurons more closely tracked the temporal statistics of target probability in our task. Finally, the session-to-session variability in a behavioral measure of attention covaried with the magnitude of this effect. Together, these results suggest that selective targeting of inhibitory neurons and networks is a critical mechanism for attentional modulation. PMID:27466133

  8. Dynamics of excitatory and inhibitory networks are differentially altered by selective attention.

    Science.gov (United States)

    Snyder, Adam C; Morais, Michael J; Smith, Matthew A

    2016-10-01

    Inhibition and excitation form two fundamental modes of neuronal interaction, yet we understand relatively little about their distinct roles in service of perceptual and cognitive processes. We developed a multidimensional waveform analysis to identify fast-spiking (putative inhibitory) and regular-spiking (putative excitatory) neurons in vivo and used this method to analyze how attention affects these two cell classes in visual area V4 of the extrastriate cortex of rhesus macaques. We found that putative inhibitory neurons had both greater increases in firing rate and decreases in correlated variability with attention compared with putative excitatory neurons. Moreover, the time course of attention effects for putative inhibitory neurons more closely tracked the temporal statistics of target probability in our task. Finally, the session-to-session variability in a behavioral measure of attention covaried with the magnitude of this effect. Together, these results suggest that selective targeting of inhibitory neurons and networks is a critical mechanism for attentional modulation. Copyright © 2016 the American Physiological Society.

  9. Fear extinction causes target-specific remodeling of perisomatic inhibitory synapses

    Science.gov (United States)

    Trouche, Stéphanie; Sasaki, Jennifer M.; Tu, Tiffany; Reijmers, Leon G.

    2013-01-01

    SUMMARY A more complete understanding of how fear extinction alters neuronal activity and connectivity within fear circuits may aid in the development of strategies to treat human fear disorders. Using a c-fos based transgenic mouse, we found that contextual fear extinction silenced basal amygdala (BA) excitatory neurons that had been previously activated during fear conditioning. We hypothesized that the silencing of BA fear neurons was caused by an action of extinction on BA inhibitory synapses. In support of this hypothesis, we found extinction-induced target-specific remodeling of BA perisomatic inhibitory synapses originating from parvalbumin and cholecystokinin-positive interneurons. Interestingly, the predicted changes in the balance of perisomatic inhibition matched the silent and active states of the target BA fear neurons. These observations suggest that target-specific changes in perisomatic inhibitory synapses represent a mechanism through which experience can sculpt the activation patterns within a neural circuit. PMID:24183705

  10. Inhibitory effect of burdock leaves on elastase and tyrosinase activity

    Science.gov (United States)

    Horng, Chi-Ting; Wu, Hsing-Chen; Chiang, Ni-Na; Lee, Chiu-Fang; Huang, Yu-Syuan; Wang, Hui-Yun; Yang, Jai-Sing; Chen, Fu-An

    2017-01-01

    Burdock (Arctium lappa L.) leaves generate a considerable amount of waste following burdock root harvest in Taiwan. To increase the use of burdock leaves, the present study investigated the optimal methods for producing burdock leaf extract (BLE) with high antioxidant polyphenolic content, including drying methods and solvent extraction concentration. In addition, the elastase and tyrosinase inhibitory activity of BLE was examined. Burdock leaves were dried by four methods: Shadow drying, oven drying, sun drying and freeze-drying. The extract solution was then subjected to total polyphenol content analysis and the method that produced BLE with the highest amount of total antioxidant components was taken forward for further analysis. The 1,1-diphenyl-2-pycrylhydrazyl scavenging, antielastase and antityrosinase activity of the BLE were measured to enable the evaluation of the antioxidant and skin aging-associated enzyme inhibitory activities of BLE. The results indicated that the total polyphenolic content following extraction with ethanol (EtOH) was highest using the freeze-drying method, followed by the oven drying, shadow drying and sun drying methods. BLE yielded a higher polyphenol content and stronger antioxidant activity as the ratio of the aqueous content of the extraction solvent used increased. BLE possesses marked tyrosinase and elastase inhibitory activities, with its antielastase activity notably stronger compared with its antityrosinase activity. These results indicate that the concentration of the extraction solvent was associated with the antioxidant and skin aging-associated enzyme inhibitory activity of BLE. The reactive oxygen species scavenging theory of skin aging may explain the tyrosinase and elastase inhibitory activity of BLE. In conclusion, the optimal method for obtaining BLE with a high antioxidant polyphenolic content was freeze-drying followed by 30–50% EtOH extraction. In addition, the antielastase and antityrosinase activities of the

  11. Analysis of glycation induced protein cross-linking inhibitory effects of some antidiabetic plants and spices.

    Science.gov (United States)

    Perera, Handunge Kumudu Irani; Handuwalage, Charith Sandaruwan

    2015-06-09

    Protein cross-linking which occurs towards the latter part of protein glycation is implicated in the development of chronic diabetic complications. Glycation induced protein cross-linking inhibitory effects of nine antidiabetic plants and three spices were evaluated in this study using a novel, simple, electrophoresis based method. Methanol extracts of thirteen plants including nine antidiabetic plants and three spices were used. Lysozyme and fructose were incubated at 37 °C in the presence or absence of different concentrations of plant extracts up to 31 days. Standard glycation inhibitor aminoguanidine and other appropriate controls were included. A recently established sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE) method was used to detect the products of protein cross-linking in the incubation mixtures. High molecular weight protein products representing the dimer, trimer and tetramer of lysozyme were detected in the presence of fructose. Among the nine antidiabetic plants, seven showed glycation induced protein cross-linking inhibitory effects namely Ficus racemosa (FR) stem bark, Gymnema sylvestre (GS) leaves, Musa paradisiaca (MP) yam, Phyllanthus debilis (PD) whole plant, Phyllanthus emblica (PE) fruit, Pterocarpus marsupium (PM) latex and Tinospora cordifolia (TC) leaves. Inhibition observed with Coccinia grandis (CG) leaves and Strychnos potatorum (SP) seeds were much low. Leaves of Gymnema lactiferum (GL), the plant without known antidiabetic effects showed the lowest inhibition. All three spices namely Coriandrum sativum (CS) seeds, Cinnamomum zeylanicum (CZ) bark and Syzygium aromaticum (SA) flower buds showed cross-link inhibitory effects with higher effects in CS and SA. PD, PE, PM, CS and SA showed almost complete inhibition on the formation of cross-linking with 25 μg/ml extracts. Methanol extracts of PD, PE, PM, CS and SA have shown promising inhibitory effects on glycation induced protein cross-linking.

  12. Macrophage migration inhibitory factor is associated with aneurysmal expansion

    DEFF Research Database (Denmark)

    Pan, Jie-Hong; Lindholt, Jes Sanddal; Sukhova, Galina K

    2003-01-01

    Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine released mainly from macrophages and activated lymphocytes. Both atherosclerosis and abdominal aortic aneurysm (AAA) are inflammatory diseases tightly linked to the function of these cells. The correlation and contribution o...... of MIF to these human diseases remain unknown, although a recent rabbit study showed expression of this cytokine in atherosclerotic lesions.......Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine released mainly from macrophages and activated lymphocytes. Both atherosclerosis and abdominal aortic aneurysm (AAA) are inflammatory diseases tightly linked to the function of these cells. The correlation and contribution...

  13. Antioxidant and protease-inhibitory potential of extracts from grains of oat

    Directory of Open Access Journals (Sweden)

    Krošlák Erik

    2016-01-01

    Full Text Available The most of important crops cultivated for production of foods and feeds could be considered as plants possessing nutraceutical or medically interesting compounds, especially if can be eaten without processing. Chemical and biological parameters that were evaluated in 100 oat (Avena sativa L. genotypes were others than those that are important in food and feed production. Contents of polyphenols and flavonoids, radical scavenging activity (DPPH, and inhibitory activities against five proteases (trypsin, thrombin, urokinase, elastase, cathepsin B were analyzed in extracts from mature grains. The antioxidant activity (DPPH correlated to the content of total polyphenols. Only a minority (15 from 100 of analyzed genotypes created separate subgroup with a high content of polyphenols, flavonoids, and high antioxidant activity. The best in these parameters were genotypes CDC-SOL-FI, Saul, and Avesta, respectively. Fifteen other genotypes assembled another minority subgroup (also 15 from 100 on the basis of their high inhibitory activities against tested proteases. The highest trypsin-, urokinase-, and elastase-inhibitory activities were in genotype Racoon, the best in thrombin-, and cathepsin B-inhibitory activities were genotypes Expression and SW Kerstin, respectively. Three oats genotypes – Rhea, AC Percy, and Detvan appeared in both subgroups.

  14. Patterned sensory nerve stimulation enhances the reactivity of spinal Ia inhibitory interneurons.

    Science.gov (United States)

    Kubota, Shinji; Hirano, Masato; Morishita, Takuya; Uehara, Kazumasa; Funase, Kozo

    2015-03-25

    Patterned sensory nerve stimulation has been shown to induce plastic changes in the reciprocal Ia inhibitory circuit. However, the mechanisms underlying these changes have not yet been elucidated in detail. The aim of the present study was to determine whether the reactivity of Ia inhibitory interneurons could be altered by patterned sensory nerve stimulation. The degree of reciprocal Ia inhibition, the conditioning effects of transcranial magnetic stimulation (TMS) on the soleus (SOL) muscle H-reflex, and the ratio of the maximum H-reflex amplitude versus maximum M-wave (H(max)/M(max)) were examined in 10 healthy individuals. Patterned electrical nerve stimulation was applied to the common peroneal nerve every 1 s (100 Hz-5 train) at the motor threshold intensity of tibialis anterior muscle to induce activity changes in the reciprocal Ia inhibitory circuit. Reciprocal Ia inhibition, the TMS-conditioned H-reflex amplitude, and H(max)/M(max) were recorded before, immediately after, and 15 min after the electrical stimulation. The patterned electrical nerve stimulation significantly increased the degree of reciprocal Ia inhibition and decreased the amplitude of the TMS-conditioned H-reflex in the short-latency inhibition phase, which was presumably mediated by Ia inhibitory interneurons. However, it had no effect on H(max)/M(max). Our results indicated that patterned sensory nerve stimulation could modulate the activity of Ia inhibitory interneurons, and this change may have been caused by the synaptic modification of Ia inhibitory interneuron terminals. These results may lead to a clearer understanding of the spinal cord synaptic plasticity produced by repetitive sensory inputs. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

  15. New polyacetylenes glycoside from Eclipta prostrate with DGAT inhibitory activity.

    Science.gov (United States)

    Meng, Xiao; Li, Ban-Ban; Lin, Xin; Jiang, Yi-Yu; Zhang, Le; Li, Hao-Ze; Cui, Long

    2018-06-08

    One new polyacetylene glycoside eprostrata Ⅰ (1), together with seven known compounds (2-8), were isolated from Eclipta prostrata. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated inhibitory activity on DGAT in an in vitro assay. Compounds 1-8 were found to exhibit inhibitory activity of DGAT1 with IC 50 values ranging from 74.4 ± 1.3 to 101.1 ± 1.1 μM.

  16. The separate roles of the reflective mind and involuntary inhibitory control in gatekeeping paranormal beliefs and the underlying intuitive confusions.

    Science.gov (United States)

    Svedholm, Annika M; Lindeman, Marjaana

    2013-08-01

    Intuitive thinking is known to predict paranormal beliefs, but the processes underlying this relationship, and the role of other thinking dispositions, have remained unclear. Study 1 showed that while an intuitive style increased and a reflective disposition counteracted paranormal beliefs, the ontological confusions suggested to underlie paranormal beliefs were predicted by individual differences in involuntary inhibitory processes. When the reasoning system was subjected to cognitive load, the ontological confusions increased, lost their relationship with paranormal beliefs, and their relationship with weaker inhibition was strongly accentuated. These findings support the argument that the confusions are mainly intuitive and that they therefore are most discernible under conditions in which inhibition is impaired, that is, when thinking is dominated by intuitive processing. Study 2 replicated the findings on intuitive and reflective thinking and paranormal beliefs. In Study 2, ontological confusions were also related to the same thinking styles as paranormal beliefs. The results support a model in which both intuitive and non-reflective thinking styles and involuntary inhibitory processes give way to embracing culturally acquired paranormal beliefs. ©2012 The British Psychological Society.

  17. Fear extinction causes target-specific remodeling of perisomatic inhibitory synapses.

    Science.gov (United States)

    Trouche, Stéphanie; Sasaki, Jennifer M; Tu, Tiffany; Reijmers, Leon G

    2013-11-20

    A more complete understanding of how fear extinction alters neuronal activity and connectivity within fear circuits may aid in the development of strategies to treat human fear disorders. Using a c-fos-based transgenic mouse, we found that contextual fear extinction silenced basal amygdala (BA) excitatory neurons that had been previously activated during fear conditioning. We hypothesized that the silencing of BA fear neurons was caused by an action of extinction on BA inhibitory synapses. In support of this hypothesis, we found extinction-induced target-specific remodeling of BA perisomatic inhibitory synapses originating from parvalbumin and cholecystokinin-positive interneurons. Interestingly, the predicted changes in the balance of perisomatic inhibition matched the silent and active states of the target BA fear neurons. These observations suggest that target-specific changes in perisomatic inhibitory synapses represent a mechanism through which experience can sculpt the activation patterns within a neural circuit. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Intra-cerebellar microinjection of histamine enhances memory consolidation of inhibitory avoidance learning in mice via H2 receptors.

    Science.gov (United States)

    Gianlorenço, A C L; Canto-de-Souza, A; Mattioli, R

    2013-12-17

    Studies have demonstrated the relationship between the histaminergic system and the cerebellum, and we intend to investigate the role of the cerebellar histaminergic system on memory consolidation. This study investigated the effect of intra-cerebellar microinjection of histamine on memory retention of inhibitory avoidance in mice, and the role of H1 and H2 receptors in it. The cerebellar vermis of male mice were implanted with guide cannulae, and after three days of recovery, the inhibitory avoidance test was performed. Immediately after a training session, animals received a microinjection of histaminergic drugs: in the experiment 1, saline (SAL) or histamine (HA 0.54, 1.36, 2.72 or 4.07 nmol); experiment 2, SAL or 1.36 nmol HA 5 min after a pretreatment with 0.16 nmol chlorpheniramine (CPA) or SAL; and experiment 3, SAL or 1.36 nmol HA 5 min after a pretreatment with 2.85 nmol ranitidine (RA) or SAL. Twenty-four hours later, a retention test was performed. The data were analyzed using one-way analysis of variance (ANOVA) and Duncan's tests. In experiment 1, animals microinjected with 1.36 nmol HA showed a higher latency to cross to the dark compartment compared to controls and to 2.72 and 4.07 nmol HA groups. In experiment 2, the combined infusions revealed difference between control (SAL+SAL) and SAL+HA and CPA+HA; while in the experiment 3 the analysis indicated differences in retention latency between mice injected with SAL+SAL and SAL+HA. The groups that received the H2 antagonist RA did not show difference compared to control. These results indicate that 1.36 nmol HA enhances memory consolidation of inhibitory avoidance learning in mice and that the pretreatment with H2 antagonist RA was able to prevent this effect. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Inhibitory effect of celecoxib on agomelatine metabolism in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    He JY

    2018-03-01

    Full Text Available Jiayang He,1 Ping Fang,2 Xiang Zheng,2 Chenchen Wang,2 Tenghui Liu,2 Bowen Zhang,2 Jian Wen,2 Ren-ai Xu3 1Department of Pharmacy, The First Hospital of Jiaxing, Jiaxing, Zhejiang, China; 2Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China; 3Department of Pharmacy, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China Aim: The aim of this study was to study the effect of celecoxib on agomelatine metabolism in vitro and in vivo. Methods: Ten healthy male Sprague–Dawley rats were randomly divided into 2 groups: Group A (control group and Group B (30 mg/kg celecoxib. Then a single dose of 20 mg/kg agomelatine was administered orally 30 min after administration of celecoxib. In an in vitro study, celecoxib with a series of concentrations was added to an incubation mixture containing recombinant human CYP2C9, human or rat liver microsomes to determine the half-maximal inhibitory concentration on the metabolism of agomelatine. Moreover, a mechanism study was performed to determine the inhibitory effect of celecoxib on CYP2C9. Results: The results showed that a single dose of 30 mg/kg celecoxib significantly increased the area under the concentration-time curve and maximum concentration of agomelatine. In addition, celecoxib inhibited the metabolism of agomelatine in the in vitro studies, which was determined to be by a competitive mechanism on CYP2C9. Those results indicated that celecoxib has an inhibitory effect on the metabolism of agomelatine both in vivo and in vitro. Conclusion: Thus, more attention should be paid when celecoxib is administered combined with agomelatine. Keywords: agomelatine, liver microsomes, pharmacokinetics, celecoxib, CYP2C9

  20. [Inhibitory mechanism of ifenprodil tartrate on rabbit platelet aggregation].

    Science.gov (United States)

    Irino, O; Saitoh, K; Hayashi, T; Ohkubo, K

    1985-05-01

    The effects of dl-erythro-4-benzyl-alpha-(4-hydroxyphenyl)-beta-methyl-l-piperidine-eth anol tartrate (ifenprodil tartrate) on rabbit platelet aggregation in vitro and ex vivo were studied. Ifenprodil tartrate inhibited platelet aggregation in vitro induced by ADP, collagen and epinephrine. It also inhibited 5-hydroxytryptamine (5-HT) uptake into platelets and 5-HT release from platelets. Since these inhibitory effects of ifenprodil tartrate on the functions of rabbit platelets were similar to the effects of imipramine, the effects of ifenprodil tartrate may be due to the stabilizing action of ifenprodil tartrate on the platelet membrane. The platelet aggregation by ADP was significantly inhibited in rabbits after oral administration of ifenprodil tartrate, the maximal plasma level of ifenprodil being reached at 20 ng/ml ex vivo, while the maximal level was only 1/40 of the minimal concentration of ifenprodil tartrate necessary to inhibit platelet aggregation in vitro. These results indicate that factors other than ifenprodil tartrate acting directly on the platelets (e.g., PGI2 which is an endogenous inhibitor of platelet aggregation) are involved in inducing the inhibitory effects of ifenprodil tartrate on platelet aggregation ex vivo. The effects of ifenprodil tartrate on both PGI2 release from the aorta and the inhibitory effects of PGI2 on platelet aggregation in vitro were investigated: PGI2 was found to intensify the inhibitory effects of ifenprodil tartrate on platelet aggregation in vitro, but there was little effect, if any, on PGI2 release. Therefore, it is considered that the ex vivo effects of ifenprodil tartrate might be due to its interaction with endogenous PGI2 in the blood.

  1. PTP1B, α-glucosidase, and DPP-IV inhibitory effects for chromene derivatives from the leaves of Smilax china L.

    Science.gov (United States)

    Zhao, Bing Tian; Le, Duc Dat; Nguyen, Phi Hung; Ali, Md Yousof; Choi, Jae-Sue; Min, Byung Sun; Shin, Heung Mook; Rhee, Hae Ik; Woo, Mi Hee

    2016-06-25

    Two new flavonoids, bismilachinone (11) and smilachinin (14), were isolated from the leaves of Smilax china L. together with 14 known compounds. Their structures were elucidated using spectroscopic methods. The PTP1B, α-glucosidase, and DPP-IV inhibitory activities of compounds 1-16 were evaluated at the molecular level. Among them, compounds 4, 7, and 10 showed moderate DPP-IV inhibitory activities with IC50 values of 20.81, 33.12, and 32.93 μM, respectively. Compounds 3, 4, 6, 11, 12, and 16 showed strong PTP1B inhibitory activities, with respective IC50 values of 7.62, 10.80, 0.92, 2.68, 9.77, and 24.17 μM compared with the IC50 value for the positive control (ursolic acid: IC50 = 1.21 μM). Compounds 2-7, 11, 12, 15, and 16 showed potent α-glucosidase inhibitory activities, with respective IC50 values of 8.70, 81.66, 35.11, 35.92, 7.99, 26.28, 11.28, 62.68, 44.32, and 70.12 μM. The positive control, acarbose, displayed an IC50 value of 175.84 μM. In the kinetic study for the PTP1B enzyme, compounds 6, 11, and 12 displayed competitive inhibition with Ki values of 3.20, 8.56, and 5.86 μM, respectively. Compounds 3, 4, and 16 showed noncompetitive inhibition with Ki values of 18.75, 5.95, and 22.86 μM, respectively. Molecular docking study for the competitive inhibitors (6, 11, and 12) radically corroborates the binding affinities and inhibition of PTP1B enzymes. These results indicated that the leaves of Smilax china L. may contain compounds with anti-diabetic activity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Assessment of attention and inhibitory control in rodent developmental neurotoxicity studies.

    Science.gov (United States)

    Driscoll, Lori L; Strupp, Barbara J

    2015-01-01

    In designing screens to assess potential neurotoxicants, the paramount goal is that the selected assessment tools detect dysfunction if it exists. This goal is particularly challenging in the case of cognitive assessments. Cognition is not a unitary phenomenon, and indeed there is growing evidence that different aspects of cognitive functioning are subserved by distinct neural systems. As a result, if a particular neurotoxicant selectively damages certain neural systems but not others, it can impair some cognitive, sensory, or affective functions, but leave many others intact. Accordingly, studies with human subjects use batteries of cognitive tests, cognizant of the fact that no one test is capable of detecting all forms of cognitive dysfunction. In contrast, assessment of cognitive functioning in non-human animal developmental neurotoxicity (DNT) studies typically consists of a single, presumably representative, "learning and memory" task that is expected to detect all potential effects on cognitive functioning. Streamlining the cognitive assessment in these studies saves time and money, but these shortcuts can have serious consequences if the aspect of cognitive functioning that is impaired is not tapped by the single selected task. In particular, executive functioning - a constellation of cognitive functions which enables the organism to focus on multiple streams of information simultaneously, and revise plans as necessary - is poorly assessed in most animal DNT studies. The failure to adequately assess these functions - which include attention, working memory, inhibitory control, and planning - is particularly worrisome in light of evidence that the neural systems that subserve these functions may be uniquely vulnerable to early developmental insults. We illustrate the importance of tapping these areas of functioning in DNT studies by describing the pattern of effects produced by early developmental Pb exposure. Rats exposed to lead (Pb) early in development

  3. Macrophage migration inhibitory factor and autism spectrum disorders

    NARCIS (Netherlands)

    Grigorenko, Elena L.; Han, Summer S.; Yrigollen, Carolyn M.; Leng, Lin; Mizue, Yuka; Anderson, George M.; Mulder, Erik J.; de Bildt, Annelies; Minderaa, Ruud B.; Volkmar, Fred R.; Chang, Joseph T.; Bucala, Richard

    OBJECTIVE. Autistic spectrum disorders are childhood neurodevelopmental disorders characterized by social and communicative impairment and repetitive and stereotypical behavior. Macrophage migration inhibitory factor (MIF) is an upstream regulator of innate immunity that promotes

  4. Kinetics of α-amylase and α-glucosidase inhibitory potential of Zea mays Linnaeus (Poaceae), Stigma maydis aqueous extract: An in vitro assessment.

    Science.gov (United States)

    Sabiu, S; O'Neill, F H; Ashafa, A O T

    2016-05-13

    Corn silk (Zea mays L., Stigma maydis) is an important herb used traditionally in many parts of the world to treat array of diseases including diabetes mellitus. Inhibitors of α-amylase and α-glucosidase offer an effective strategy to modulate levels of post prandial hyperglycaemia via control of starch metabolism. This study evaluated α-amylase and α-glucosidase inhibitory potentials of corn silk aqueous extract. Active principles and antioxidant attributes of the extract were also analysed. The α-amylase inhibitory potential of the extract was investigated by reacting its different concentrations with α-amylase and starch solution, while α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extract followed by addition of p-nitrophenylglucopyranoside. The mode(s) of inhibition of the enzymes were determined using Lineweaver-Burke plot. In vitro analysis of the extract showed that it exhibited potent and moderate inhibitory potential against α-amylase and α-glucosidase, respectively. The inhibition was concentration-dependent with respective half-maximal inhibitory concentration (IC50) values of 5.89 and 0.93mg/mL. Phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols, saponins, tannins and phytosterols as probable inhibitory constituents. Furthermore, the extract remarkably scavenges reactive oxygen species like DPPH and nitric oxide radicals, elicited good reducing power and a significant metal chelating attributes. Overall, the non-competitive and uncompetitive mechanism of action of corn silk extract is due to its inhibitory effects on α-amylase and α-glucosidase, respectively. Consequently, this will reduce the rate of starch hydrolysis, enhance palliated glucose levels, and thus, lending credence to hypoglycaemic candidature of corn silk. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Deciphering the role of CA1 inhibitory circuits in sharp wave-ripple complexes.

    Science.gov (United States)

    Cutsuridis, Vassilis; Taxidis, Jiannis

    2013-01-01

    Sharp wave-ripples (SWRs) are population oscillatory patterns in hippocampal LFPs during deep sleep and immobility, involved in the replay of memories acquired during wakefulness. SWRs have been extensively studied, but their exact generation mechanism is still unknown. A computational model has suggested that fast perisomatic inhibition may generate the high frequency ripples (~200 Hz). Another model showed how replay of memories can be controlled by various classes of inhibitory interneurons targeting specific parts of pyramidal cells (PC) and firing at particular SWR phases. Optogenetic studies revealed new roles for interneuronal classes and rich dynamic interplays between them, shedding new light in their potential role in SWRs. Here, we integrate these findings in a conceptual model of how dendritic and somatic inhibition may collectively contribute to the SWR generation. We suggest that sharp wave excitation and basket cell (BC) recurrent inhibition synchronises BC spiking in ripple frequencies. This rhythm is imposed on bistratified cells which prevent pyramidal bursting. Axo-axonic and stratum lacunosum/moleculare interneurons are silenced by inhibitory inputs originating in the medial septum. PCs receiving rippling inhibition in both dendritic and perisomatic areas and excitation in their apical dendrites, exhibit sparse ripple phase-locked spiking.

  6. Do personality traits predict individual differences in excitatory and inhibitory learning?

    Directory of Open Access Journals (Sweden)

    Zhimin eHe

    2013-05-01

    Full Text Available Conditioned inhibition (CI is demonstrated in classical conditioning when a stimulus is used to signal the omission of an otherwise expected outcome. This basic learning ability is involved in a wide range of normal behaviour - and thus its disruption could produce a correspondingly wide range of behavioural deficits. The present study employed a computer-based task to measure conditioned excitation and inhibition in the same discrimination procedure. Conditioned inhibition by summation test was clearly demonstrated. Additionally summary measures of excitatory and inhibitory learning (difference scores were calculated in order to explore how performance related to individual differences in a large sample of normal participants (n=176 following exclusion of those not meeting the basic learning criterion. The individual difference measures selected derive from two biologically-based personality theories, Gray’s reinforcement sensitivity theory (1982 and Eysenck’s psychoticism, extraversion and neuroticism theory (1991. Following the behavioural tasks, participants completed the behavioural inhibition system/behavioural activation system scales (BIS/BAS and the Eysenck personality questionnaire revised short scale (EPQ-RS. Analyses of the relationship between scores on each of the scales and summary measures of excitatory and inhibitory learning suggested that those with higher BAS (specifically the drive sub-scale and higher EPQ-RS neuroticism showed reduced levels of excitatory conditioning. Inhibitory conditioning was similarly attenuated in those with higher EPQ-RS neuroticism, as well as in those with higher BIS scores. Thus the findings are consistent with higher levels of neuroticism being accompanied by generally impaired associative learning, both inhibitory and excitatory. There was also evidence for some dissociation in the effects of behavioural activation and behavioural inhibition on excitatory and inhibitory learning respectively.

  7. Single-molecule analysis of inhibitory pausing states of V1-ATPase.

    Science.gov (United States)

    Uner, Naciye Esma; Nishikawa, Yoshihiro; Okuno, Daichi; Nakano, Masahiro; Yokoyama, Ken; Noji, Hiroyuki

    2012-08-17

    V(1)-ATPase, the hydrophilic V-ATPase domain, is a rotary motor fueled by ATP hydrolysis. Here, we found that Thermus thermophilus V(1)-ATPase shows two types of inhibitory pauses interrupting continuous rotation: a short pause (SP, 4.2 s) that occurred frequently during rotation, and a long inhibitory pause (LP, >30 min) that terminated all active rotations. Both pauses occurred at the same angle for ATP binding and hydrolysis. Kinetic analysis revealed that the time constants of inactivation into and activation from the SP were too short to represent biochemically predicted ADP inhibition, suggesting that SP is a newly identified inhibitory state of V(1)-ATPase. The time constant of inactivation into LP was 17 min, consistent with one of the two time constants governing the inactivation process observed in bulk ATPase assay. When forcibly rotated in the forward direction, V(1) in LP resumed active rotation. Solution ADP suppressed the probability of mechanical activation, suggesting that mechanical rotation enhanced inhibitory ADP release. These features were highly consistent with mechanical activation of ADP-inhibited F(1), suggesting that LP represents the ADP-inhibited state of V(1)-ATPase. Mechanical activation largely depended on the direction and angular displacement of forced rotation, implying that V(1)-ATPase rotation modulates the off rate of ADP.

  8. Inhibitory effects of sanguinarine against the cyanobacterium Microcystis aeruginosa NIES-843 and possible mechanisms of action

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Jihai [College of Resources and Environment, Hunan Agricultural University, Changsha 410128 (China); Hunan Provincial Key Laboratory of Farmland Pollution Control and Agricultural Resources Use, Hunan Agricultural University, Changsha 410128 (China); Liu, Deming [State Key Laboratory Breeding Base of Crop Germplasm Innovation and Resource Utilization, Hunan Agricultural University, Changsha 410128 (China); Gong, Daoxin; Zeng, Qingru; Yan, Zhiyong [College of Resources and Environment, Hunan Agricultural University, Changsha 410128 (China); Gu, Ji-Dong, E-mail: jdgu@hku.hk [Hunan Provincial Key Laboratory of Farmland Pollution Control and Agricultural Resources Use, Hunan Agricultural University, Changsha 410128 (China); Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Hong Kong SAR (China)

    2013-10-15

    Highlights: •Sanguinarine was found as a strong algicidal biologically derived substance. •Sanguinarine can induce oxidative stress in the cells of Microcystis aeruginosa. •Photosystem is a target of toxicity of sanguinarine on M. aeruginosa. •Sanguinarine can induce DNA damage and inhibit cell division. -- Abstract: Sanguinarine showed strong inhibitory effect against Microcystis aeruginosa, a typical water bloom-forming and microcystins-producing cyanobacterium. The EC50 of sanguinarine against the growth of M. aeruginosa NIES-843 was 34.54 ± 1.17 μg/L. Results of chlorophyll fluorescence transient analysis indicated that all the electron donating side, accepting side, and the reaction center of the Photosystem II (PS II) were the targets of sanguinarine against M. aeruginosa NIES-843. The elevation of reactive oxygen species (ROS) level in the cells of M. aeruginosa NIES-843 upon exposure indicated that sanguinarine induced oxidative stress in the active growing cells of M. aeruginosa NIES-843. Further results of gene expression analysis indicated that DNA damage and cell division inhibition were also involved in the inhibitory action mechanism of sanguinarine against M. aeruginosa NIES-843. The inhibitory characteristics of sanguinarine against M. aeruginosa suggest that the ecological- and public health-risks need to be evaluated before its application in cyanobacterial bloom control to avoid devastating events irreversibly.

  9. Novel nootropic dipeptide Noopept increases inhibitory synaptic transmission in CA1 pyramidal cells.

    Science.gov (United States)

    Kondratenko, Rodion V; Derevyagin, Vladimir I; Skrebitsky, Vladimir G

    2010-05-31

    Effects of newly synthesized nootropic and anxiolytic dipeptide Noopept on inhibitory synaptic transmission in hippocampal CA1 pyramidal cells were investigated using patch-clamp technique in whole-cell configuration. Bath application of Noopept (1 microM) significantly increased the frequency of spike-dependant spontaneous IPSCs whereas spike-independent mIPSCs remained unchanged. It was suggested that Noopept mediates its effect due to the activation of inhibitory interneurons terminating on CA1 pyramidal cells. Results of current clamp recording of inhibitory interneurons residing in stratum radiatum confirmed this suggestion. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  10. The Size of Activating and Inhibitory Killer Ig-like Receptor Nanoclusters Is Controlled by the Transmembrane Sequence and Affects Signaling

    Directory of Open Access Journals (Sweden)

    Anna Oszmiana

    2016-05-01

    Full Text Available Super-resolution microscopy has revealed that immune cell receptors are organized in nanoscale clusters at cell surfaces and immune synapses. However, mechanisms and functions for this nanoscale organization remain unclear. Here, we used super-resolution microscopy to compare the surface organization of paired killer Ig-like receptors (KIR, KIR2DL1 and KIR2DS1, on human primary natural killer cells and cell lines. Activating KIR2DS1 assembled in clusters two-fold larger than its inhibitory counterpart KIR2DL1. Site-directed mutagenesis established that the size of nanoclusters is controlled by transmembrane amino acid 233, a lysine in KIR2DS1. Super-resolution microscopy also revealed two ways in which the nanoscale clustering of KIR affects signaling. First, KIR2DS1 and DAP12 nanoclusters are juxtaposed in the resting cell state but coalesce upon receptor ligation. Second, quantitative super-resolution microscopy revealed that phosphorylation of the kinase ZAP-70 or phosphatase SHP-1 is favored in larger KIR nanoclusters. Thus, the size of KIR nanoclusters depends on the transmembrane sequence and affects downstream signaling.

  11. Assessment of the inhibitory effects of pyrethroids against human carboxylesterases

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Wei [The Second Affiliated Hospital of Dalian Medical University, Dalian 110623 (China); Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Wang, Dan-Dan; Dou, Tong-Yi [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Hou, Jie [Dalian Medical University, Dalian 116044 (China); Feng, Liang; Yin, Heng [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Luo, Qun [Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Sun, Jie [The Second Affiliated Hospital of Dalian Medical University, Dalian 110623 (China); Ge, Guang-Bo, E-mail: geguangbo@dicp.ac.cn [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Yang, Ling [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2017-04-15

    Pyrethroids are broad-spectrum insecticides that widely used in many countries, while humans may be exposed to these toxins by drinking or eating pesticide-contaminated foods. This study aimed to investigate the inhibitory effects of six commonly used pyrethroids against two major human carboxylesterases (CES) including CES1 and CES2. Three optical probe substrates for CES1 (DME, BMBT and DMCB) and a fluorescent probe substrate for CES2 (DDAB) were used to characterize the inhibitory effects of these pyrethroids. The results demonstrated that most of the tested pyrethroids showed moderate to weak inhibitory effects against both CES1 and CES2, but deltamethrin displayed strong inhibition towards CES1. The IC{sub 50} values of deltamethrin against CES1-mediated BMBT, DME, and DMCB hydrolysis were determined as 1.58 μM, 2.39 μM, and 3.3 μM, respectively. Moreover, deltamethrin was cell membrane permeable and capable of inhibition endogenous CES1 in living cells. Further investigation revealed that deltamethrin inhibited CES1-mediated BMBT hydrolysis via competitive manner but noncompetitively inhibited DME or DMCB hydrolysis. The inhibition behaviors of deltamethrin against CES1 were also studied by molecular docking simulation. The results demonstrated that CES1 had at least two different ligand-binding sites, one was the DME site and another was the BMBT site which was identical to the binding site of deltamethrin. In summary, deltamethrin was a strong reversible inhibitor against CES1 and it could tightly bind on CES1 at the same ligand-binding site as BMBT. These findings are helpful for the deep understanding of the interactions between xenobiotics and CES1. - Highlights: • The inhibitory effects of six commonly used pyrethroids on human carboxylesterases were investigated. • Deltamethrin displayed strong inhibitory effects against human carboxylesterase 1 (CES1). • Deltamethrin was cell membrane permeable and could inhibit intracellular CES1 in living

  12. Assessment of the inhibitory effects of pyrethroids against human carboxylesterases

    International Nuclear Information System (INIS)

    Lei, Wei; Wang, Dan-Dan; Dou, Tong-Yi; Hou, Jie; Feng, Liang; Yin, Heng; Luo, Qun; Sun, Jie; Ge, Guang-Bo; Yang, Ling

    2017-01-01

    Pyrethroids are broad-spectrum insecticides that widely used in many countries, while humans may be exposed to these toxins by drinking or eating pesticide-contaminated foods. This study aimed to investigate the inhibitory effects of six commonly used pyrethroids against two major human carboxylesterases (CES) including CES1 and CES2. Three optical probe substrates for CES1 (DME, BMBT and DMCB) and a fluorescent probe substrate for CES2 (DDAB) were used to characterize the inhibitory effects of these pyrethroids. The results demonstrated that most of the tested pyrethroids showed moderate to weak inhibitory effects against both CES1 and CES2, but deltamethrin displayed strong inhibition towards CES1. The IC 50 values of deltamethrin against CES1-mediated BMBT, DME, and DMCB hydrolysis were determined as 1.58 μM, 2.39 μM, and 3.3 μM, respectively. Moreover, deltamethrin was cell membrane permeable and capable of inhibition endogenous CES1 in living cells. Further investigation revealed that deltamethrin inhibited CES1-mediated BMBT hydrolysis via competitive manner but noncompetitively inhibited DME or DMCB hydrolysis. The inhibition behaviors of deltamethrin against CES1 were also studied by molecular docking simulation. The results demonstrated that CES1 had at least two different ligand-binding sites, one was the DME site and another was the BMBT site which was identical to the binding site of deltamethrin. In summary, deltamethrin was a strong reversible inhibitor against CES1 and it could tightly bind on CES1 at the same ligand-binding site as BMBT. These findings are helpful for the deep understanding of the interactions between xenobiotics and CES1. - Highlights: • The inhibitory effects of six commonly used pyrethroids on human carboxylesterases were investigated. • Deltamethrin displayed strong inhibitory effects against human carboxylesterase 1 (CES1). • Deltamethrin was cell membrane permeable and could inhibit intracellular CES1 in living cells

  13. Cognitive Control Over Immediate Reward in Binge Alcohol Drinkers.

    Science.gov (United States)

    Poulton, Antoinette; Mackenzie, Caitlyn; Harrington, Kaitlyn; Borg, Sarah; Hester, Robert

    2016-02-01

    Cognitive control deficits, as captured by inhibitory control measures, are indicative of increased impulsivity and are considered a marker for substance use disorder vulnerability. While individuals with alcohol use disorder (AUD) typically exhibit inhibitory control dysfunction, evidence of impaired inhibitory control among harmful drinkers, who are at increased risk of developing an AUD, is mixed. This study examined the response inhibition of binge drinkers using a task that employed neutral, as well as both immediate and delayed reward contingencies, to determine whether reward induced heightened impulsivity in this population. Binge alcohol users (n = 42) and controls (n = 42) were administered a Monetary Incentive Control Task that required participants to successfully inhibit a prepotent motor response to both neutral and immediately rewarding stimuli in order to secure a large delayed reward. Binge drinkers had significantly worse response inhibition than controls irrespective of trial condition and even after controlling for differences in weekly intake. Although both binge and control participants exhibited significantly worse inhibitory control in the presence of immediate reward, the control group showed a greater reduction in inhibition accuracy compared to the binge group in reward relative to neutral conditions. Both groups demonstrated significantly enhanced control when forewarned there was an increased chance response inhibition would be required. Control participants secured the delayed reward more often than binge participants. Despite the variability in the literature, this study demonstrated consistent generalized impulse control deficits among binge-drinking individuals that were unrelated to reward manipulations. These findings point to mechanisms that may confer vulnerability for transition from binge drinking to AUD. Copyright © 2016 by the Research Society on Alcoholism.

  14. Correlation between enzymes inhibitory effects and antioxidant ...

    African Journals Online (AJOL)

    ... and phytochemical content of fractions was investigated. The n-butanol fraction showed significant α-glucosidase and α-amylase inhibitory effects (IC50 values 15.1 and 39.42 μg/ml, respectively) along with the remarkable antioxidant activity when compared to the other fractions. High performance liquid chromatography ...

  15. Assessment of inhibitory potential of essential oils on natural mycoflora and Fusarium mycotoxins production in wheat.

    Science.gov (United States)

    Sumalan, Renata-Maria; Alexa, Ersilia; Poiana, Mariana-Atena

    2013-02-14

    In the last years essential oils from different plants were used in the prevention of fungi and mycotoxins accumulation in cereals. The most attractive aspect derived from using of essential oils as seed grains protectants is due to their non-toxicity. This study was focused on assessment the inhibitory effect of some essential oils: Melissa officinalis (O1), Salvia officinalis (O2), Coriandrum sativum (O3), Thymus vulgaris (O4) Mentha piperita (O5) and Cinnamomum zeylanicum (O6) against natural mycoflora and Fusarium mycotoxins production correlated with their antioxidants properties. All essential oils showed inhibitory effect on fungal contamination of wheat seeds. This ability was dose-dependent. The highest inhibitory effect on Fusarium and Aspergillus fungi was recorded after 5 days of treatment. Fungi such as yeast (Pichia, Saccharomyces and Hyphopichia) were predominantly on seeds mycoflora after 22 days. Each treatment had a selective inhibitory effect on frequency of fungus genera. After 5 days of treatment the most fungicidal effect was recorder for O4, followed by O1. In terms of essential oils effect on mycotoxins development, the best control on fumonisins (FUMO) production was recorded for O6. The antioxidant properties of essential oils decreased in order: O4 > O1 > O6 > O5 > O2 > O3. Also, our data suggested that there is a significant negative correlation between antioxidant properties and seed contamination index (SCI), but there was not recorded a good correlation between antioxidant properties and FUMO content. Based on proven antifungal and antimycotoxin effects as well as their antioxidant properties, the essential oils could be recommended as natural preservatives for stored cereals. The highest inhibition of fungal growth was noted after 5 days of treatment and decreased after 22 days.

  16. Assessment of inhibitory potential of essential oils on natural mycoflora and Fusarium mycotoxins production in wheat

    Science.gov (United States)

    2013-01-01

    Background In the last years essential oils from different plants were used in the prevention of fungi and mycotoxins accumulation in cereals. The most attractive aspect derived from using of essential oils as seed grains protectants is due to their non-toxicity. This study was focused on assessment the inhibitory effect of some essential oils: Melissa officinalis (O1), Salvia officinalis (O2), Coriandrum sativum (O3), Thymus vulgaris (O4) Mentha piperita (O5) and Cinnamomum zeylanicum (O6) against natural mycoflora and Fusarium mycotoxins production correlated with their antioxidants properties. Results All essential oils showed inhibitory effect on fungal contamination of wheat seeds. This ability was dose-dependent. The highest inhibitory effect on Fusarium and Aspergillus fungi was recorded after 5 days of treatment. Fungi such as yeast (Pichia, Saccharomyces and Hyphopichia) were predominantly on seeds mycoflora after 22 days. Each treatment had a selective inhibitory effect on frequency of fungus genera. After 5 days of treatment the most fungicidal effect was recorder for O4, followed by O1. In terms of essential oils effect on mycotoxins development, the best control on fumonisins (FUMO) production was recorded for O6. The antioxidant properties of essential oils decreased in order: O4 > O1 > O6 > O5 > O2 > O3. Also, our data suggested that there is a significant negative correlation between antioxidant properties and seed contamination index (SCI), but there was not recorded a good correlation between antioxidant properties and FUMO content. Conclusions Based on proven antifungal and antimycotoxin effects as well as their antioxidant properties, the essential oils could be recommended as natural preservatives for stored cereals. The highest inhibition of fungal growth was noted after 5 days of treatment and decreased after 22 days. PMID:23409841

  17. Sub-inhibitory concentrations of heavy metals facilitate the horizontal transfer of plasmid-mediated antibiotic resistance genes in water environment.

    Science.gov (United States)

    Zhang, Ye; Gu, April Z; Cen, Tianyu; Li, Xiangyang; He, Miao; Li, Dan; Chen, Jianmin

    2018-06-01

    Although widespread antibiotic resistance has been mostly attributed to the selective pressure generated by overuse and misuse of antibiotics, recent growing evidence suggests that chemicals other than antibiotics, such as certain metals, can also select and stimulate antibiotic resistance via both co-resistance and cross-resistance mechanisms. For instance, tetL, merE, and oprD genes are resistant to both antibiotics and metals. However, the potential de novo resistance induced by heavy metals at environmentally-relevant low concentrations (much below theminimum inhibitory concentrations [MICs], also referred as sub-inhibitory) has hardly been explored. This study investigated and revealed that heavy metals, namely Cu(II), Ag(I), Cr(VI), and Zn(II), at environmentally-relevant and sub-inhibitory concentrations, promoted conjugative transfer of antibiotic resistance genes (ARGs) between E. coli strains. The mechanisms of this phenomenon were further explored, which involved intracellular reactive oxygen species (ROS) formation, SOS response, increased cell membrane permeability, and altered expression of conjugation-relevant genes. These findings suggest that sub-inhibitory levels of heavy metals that widely present in various environments contribute to the resistance phenomena via facilitating horizontal transfer of ARGs. This study provides evidence from multiple aspects implicating the ecological effect of low levels of heavy metals on antibiotic resistance dissemination and highlights the urgency of strengthening efficacious policy and technology to control metal pollutants in the environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Inhibitory Gating of Basolateral Amygdala Inputs to the Prefrontal Cortex.

    Science.gov (United States)

    McGarry, Laura M; Carter, Adam G

    2016-09-07

    Interactions between the prefrontal cortex (PFC) and basolateral amygdala (BLA) regulate emotional behaviors. However, a circuit-level understanding of functional connections between these brain regions remains incomplete. The BLA sends prominent glutamatergic projections to the PFC, but the overall influence of these inputs is predominantly inhibitory. Here we combine targeted recordings and optogenetics to examine the synaptic underpinnings of this inhibition in the mouse infralimbic PFC. We find that BLA inputs preferentially target layer 2 corticoamygdala over neighboring corticostriatal neurons. However, these inputs make even stronger connections onto neighboring parvalbumin and somatostatin expressing interneurons. Inhibitory connections from these two populations of interneurons are also much stronger onto corticoamygdala neurons. Consequently, BLA inputs are able to drive robust feedforward inhibition via two parallel interneuron pathways. Moreover, the contributions of these interneurons shift during repetitive activity, due to differences in short-term synaptic dynamics. Thus, parvalbumin interneurons are activated at the start of stimulus trains, whereas somatostatin interneuron activation builds during these trains. Together, these results reveal how the BLA impacts the PFC through a complex interplay of direct excitation and feedforward inhibition. They also highlight the roles of targeted connections onto multiple projection neurons and interneurons in this cortical circuit. Our findings provide a mechanistic understanding for how the BLA can influence the PFC circuit, with important implications for how this circuit participates in the regulation of emotion. The prefrontal cortex (PFC) and basolateral amygdala (BLA) interact to control emotional behaviors. Here we show that BLA inputs elicit direct excitation and feedforward inhibition of layer 2 projection neurons in infralimbic PFC. BLA inputs are much stronger at corticoamygdala neurons compared

  19. In silico, in vitro and in vivo analyses of dipeptidyl peptidase IV inhibitory activity and the antidiabetic effect of sodium caseinate hydrolysate.

    Science.gov (United States)

    Hsieh, Cheng-Hong; Wang, Tzu-Yuan; Hung, Chuan-Chuan; Jao, Chia-Ling; Hsieh, You-Liang; Wu, Si-Xian; Hsu, Kuo-Chiang

    2016-02-01

    The frequency (A), a novel in silico parameter, was developed by calculating the ratio of the number of truncated peptides with Xaa-proline and Xaa-alanine to all peptide fragments from a protein hydrolyzed with a specific protease. The highest in vitro DPP-IV inhibitory activity (72.7%) was observed in the hydrolysate of sodium caseinate by bromelain (Cas/BRO), and the constituent proteins of bovine casein also had relatively high A values (0.10-0.17) with BRO hydrolysis. 1CBR (the <1 kDa fraction of Cas/BRO) showed the greatest in vitro DPP-IV inhibitory activity of 77.5% and was used for in vivo test by high-fat diet-fed and low-dose streptozotocin-induced diabetic rats. The daily administration of 1CBR for 6 weeks was effective to improve glycaemic control in diabetic rats. The results indicate that the novel in silico method has the potential as a screening tool to predict dietary proteins to generate DPP-IV inhibitory and antidiabetic peptides.

  20. Systematic review of ERP and fMRI studies investigating inhibitory control and error processing in people with substance dependence and behavioural addictions

    Science.gov (United States)

    Luijten, Maartje; Machielsen, Marise W.J.; Veltman, Dick J.; Hester, Robert; de Haan, Lieuwe; Franken, Ingmar H.A.

    2014-01-01

    Background Several current theories emphasize the role of cognitive control in addiction. The present review evaluates neural deficits in the domains of inhibitory control and error processing in individuals with substance dependence and in those showing excessive addiction-like behaviours. The combined evaluation of event-related potential (ERP) and functional magnetic resonance imaging (fMRI) findings in the present review offers unique information on neural deficits in addicted individuals. Methods We selected 19 ERP and 22 fMRI studies using stop-signal, go/no-go or Flanker paradigms based on a search of PubMed and Embase. Results The most consistent findings in addicted individuals relative to healthy controls were lower N2, error-related negativity and error positivity amplitudes as well as hypoactivation in the anterior cingulate cortex (ACC), inferior frontal gyrus and dorsolateral prefrontal cortex. These neural deficits, however, were not always associated with impaired task performance. With regard to behavioural addictions, some evidence has been found for similar neural deficits; however, studies are scarce and results are not yet conclusive. Differences among the major classes of substances of abuse were identified and involve stronger neural responses to errors in individuals with alcohol dependence versus weaker neural responses to errors in other substance-dependent populations. Limitations Task design and analysis techniques vary across studies, thereby reducing comparability among studies and the potential of clinical use of these measures. Conclusion Current addiction theories were supported by identifying consistent abnormalities in prefrontal brain function in individuals with addiction. An integrative model is proposed, suggesting that neural deficits in the dorsal ACC may constitute a hallmark neurocognitive deficit underlying addictive behaviours, such as loss of control. PMID:24359877

  1. Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Murata, H; Iio, M; Yamada, H; Chiba, K [Tokyo Metropolitan Geriatric Medical Center (Japan); Kobayashi, M

    1975-08-01

    To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10/sup -3/ ..mu..g/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO/sub 4/-, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 67/Ga-citrate and /sup 57/Co-bleomycin as they were supplied. /sup 111/In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, /sup 131/I-PVP, /sup 59/FeCl/sub 3/, Na-phosphate (/sup 32/P), /sup 198/Au-colloid and /sup 75/Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used /sup 169/Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10/sup -3/ ..mu..g/ml due to addition of a small amount of benzyl alcohol. /sup 131/I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 198/Au-colloid, /sup 57/Co-bleomycin and /sup 75/Se-selenomethionine.

  2. Phenotypic characterisation and assessment of the inhibitory ...

    African Journals Online (AJOL)

    Six strains of Lactobacillus spp. were isolated from fermenting corn slurry, fresh cow milk, and the faeces of pig, albino rat, and human infant. Their inhibitory action was tested against some spoilage and pathogenic bacteria. Lactobacillus acidophilus isolated from milk was found to display a higher antagonistic effect with ...

  3. Phenotypic characterisation and assessment of the inhibitory ...

    African Journals Online (AJOL)

    Fred

    inhibitory potential of Lactobacillus isolates from different sources. Oyetayo, V.O.. Department of ... Six strains of Lactobacillus spp. were isolated from fermenting corn slurry, fresh cow milk, and the faeces of pig, albino rat, and human ... the growth of some pathogens by Lactobacillus reuteri BSA 13, obtained from pig faeces.

  4. Inhibitory Effects of 5,6,7-Trihydroxyflavones on Tyrosinase

    Directory of Open Access Journals (Sweden)

    Jun Kawabata

    2007-01-01

    Full Text Available Baicalein (1, 6-hydroxyapigenin (6, 6-hydroxygalangin (13 and 6-hydroxy-kaempferol (14, which are naturally occurring flavonoids from a set of 14 hydroxy-flavones tested, exhibited high inhibitory effects on tyrosinase with respect to L-DOPA,while each of the 5,6,7-trihydroxyflavones 1, 6, 13 or 14 acted as a cofactor tomonophenolase. Moreover, 6-hydroxykaempferol (14 showed the highest activity andwas a competitive inhibitor of tyrosinase compared to L-DOPA. 5,6,7-Trihydroxyflavones 1, 6, 13 or 14 showed also high antioxidant activities. Hence, weconclude that the 5,6,7-trihydroxy-flavones are useful as good depigmentation agentswith inhibitory effects in addition to their antioxidant properties.

  5. Facilitatory and inhibitory pain mechanisms are altered in patients with carpal tunnel syndrome.

    Directory of Open Access Journals (Sweden)

    Benjamin Soon

    Full Text Available Preliminary evidence from studies using quantitative sensory testing suggests the presence of central mechanisms in patients with carpal tunnel syndrome (CTS as apparent by widespread hyperalgesia. Hallmarks of central mechanisms after nerve injuries include nociceptive facilitation and reduced endogenous pain inhibition. Methods to study nociceptive facilitation in CTS so far have been limited to quantitative sensory testing and the integrity of endogenous inhibition remains unexamined. The aim of this study was therefore to investigate changes in facilitatory and inhibitory processing in patients with CTS by studying hypersensitivity following experimentally induced pain (facilitatory mechanisms and the efficacy of conditioned pain modulation (CPM, inhibitory mechanisms. Twenty-five patients with mild to moderate CTS and 25 age and sex matched control participants without CTS were recruited. Increased pain facilitation was evaluated via injection of hypertonic saline into the upper trapezius. Altered pain inhibition through CPM was investigated through cold water immersion of the foot as the conditioning stimulus and pressure pain threshold over the thenar and hypothenar eminence bilaterally as the test stimulus. The results demonstrated that patients with CTS showed a greater duration (p = 0.047, intensity (p = 0.044 and area (p = 0.012 of pain in response to experimentally induced pain in the upper trapezius and impaired CPM compared to the control participants (p = 0.006. Although typically considered to be driven by peripheral mechanisms, these findings indicate that CTS demonstrates characteristics of altered central processing with increased pain facilitation and reduced endogenous pain inhibition.

  6. Dynamics of Time Delay-Induced Multiple Synchronous Behaviors in Inhibitory Coupled Neurons

    Science.gov (United States)

    Gu, Huaguang; Zhao, Zhiguo

    2015-01-01

    The inhibitory synapse can induce synchronous behaviors different from the anti-phase synchronous behaviors, which have been reported in recent studies. In the present paper, synchronous behaviors are investigated in the motif model composed of reciprocal inhibitory coupled neurons with endogenous bursting and time delay. When coupling strength is weak, synchronous behavior appears at a single interval of time delay within a bursting period. When coupling strength is strong, multiple synchronous behaviors appear at different intervals of time delay within a bursting period. The different bursting patterns of synchronous behaviors, and time delays and coupling strengths that can induce the synchronous bursting patterns can be well interpreted by the dynamics of the endogenous bursting pattern of isolated neuron, which is acquired by the fast-slow dissection method, combined with the inhibitory coupling current. For an isolated neuron, when a negative impulsive current with suitable strength is applied at different phases of the bursting, multiple different bursting patterns can be induced. For a neuron in the motif, the inhibitory coupling current, of which the application time and strength is modulated by time delay and coupling strength, can cause single or multiple synchronous firing patterns like the negative impulsive current when time delay and coupling strength is suitable. The difference compared to the previously reported multiple synchronous behaviors that appear at time delays wider than a period of the endogenous firing is discussed. The results present novel examples of synchronous behaviors in the neuronal network with inhibitory synapses and provide a reasonable explanation. PMID:26394224

  7. Structural Requirements of Alkylglyceryl-l-Ascorbic Acid Derivatives for Melanogenesis Inhibitory Activity.

    Science.gov (United States)

    Taira, Norihisa; Katsuyama, Yushi; Yoshioka, Masato; Muraoka, Osamu; Morikawa, Toshio

    2018-04-10

    l-Ascorbic acid has multifunctional benefits on skin aesthetics, including inhibition of melanin production, and is widely used in cosmetics. It, however, has low stability and poor skin penetration. We hypothesize that alkylglyceryl-l-ascorbic acid derivatives, highly stable vitamin C-alkylglycerol conjugates, would have similar anti-melanogenic activity with better stability and penetration. We test 28 alkylglyceryl-l-ascorbic acid derivatives ( 1 - 28 ) on theophylline-stimulated B16 melanoma 4A5 cells to determine if they inhibit melanogenesis and establish any structure-function relationships. Although not the most potent inhibitors, 3- O -(2,3-dihydroxypropyl)-2- O -hexyl-l-ascorbic acid ( 6 , IC 50 = 81.4 µM) and 2- O -(2,3-dihydroxypropyl)-3- O -hexyl-l-ascorbic acid ( 20 , IC 50 = 117 µM) are deemed the best candidate derivatives based on their inhibitory activities and low toxicities. These derivatives are also found to be more stable than l-ascorbic acid and to have favorable characteristics for skin penetration. The following structural requirements for inhibitory activity of alkylglyceryl-l-ascorbic acid derivatives are also determined: (i) alkylation of glyceryl-l-ascorbic acid is essential for inhibitory activity; (ii) the 3- O -alkyl-derivatives ( 2 - 14 ) exhibit stronger inhibitory activity than the corresponding 2- O -alkyl-derivatives ( 16 - 28 ); and (iii) derivatives with longer alkyl chains have stronger inhibitory activities. Mechanistically, our studies suggest that l-ascorbic acid derivatives exert their effects by suppressing the mRNA expression of tyrosinase and tyrosine-related protein-1.

  8. Inhibitory Interneurons, Oxidative Stress, and Schizophrenia

    OpenAIRE

    Sullivan, Elyse M.; O’Donnell, Patricio

    2012-01-01

    Translational studies are becoming more common in schizophrenia research. The past couple of decades witnessed the emergence of novel ideas regarding schizophrenia pathophysiology that originated from both human and animal studies. The findings that glutamate and gamma-aminobutyric acid transmission are affected in the disease led to the hypothesis of altered inhibitory neurotransmission as critical for cognitive deficits and to an exploration of novel therapeutic approaches aimed at restorin...

  9. Self-reported Physical Activity Predicts Pain Inhibitory and Facilitatory Function

    Science.gov (United States)

    Naugle, Kelly M.; Riley, Joseph L.

    2013-01-01

    Considerable evidence suggests regular physical activity can reduce chronic pain symptoms. Dysfunction of endogenous facilitatory and inhibitory systems has been implicated in multiple chronic pain conditions. However, few studies have investigated the relationship between levels of physical activity and descending pain modulatory function. Purpose This study’s purpose was to determine whether self-reported levels of physical activity in healthy adults predicted 1) pain sensitivity to heat and cold stimuli, 2) pain facilitatory function as tested by temporal summation of pain (TS), and 3) pain inhibitory function as tested by conditioned pain modulation (CPM) and offset analgesia. Methods Forty-eight healthy adults (age range 18–76) completed the International Physical Activity Questionnaire (IPAQ) and the following pain tests: heat pain thresholds (HPT), heat pain suprathresholds, cold pressor pain (CPP), temporal summation of heat pain, conditioned pain modulation, and offset analgesia. The IPAQ measured levels of walking, moderate, vigorous and total physical activity over the past seven days. Hierarchical linear regressions were conducted to determine the relationship between each pain test and self-reported levels of physical activity, while controlling for age, sex and psychological variables. Results Self-reported total and vigorous physical activity predicted TS and CPM (p’s pain and greater CPM. The IPAQ measures did not predict any of the other pain measures. Conclusion Thus, these results suggest that healthy older and younger adults who self-report greater levels of vigorous and total physical activity exhibit enhanced descending pain modulatory function. Improved descending pain modulation may be a mechanism through which exercise reduces or prevents chronic pain symptoms. PMID:23899890

  10. Inhibitory effect on nitric oxide production and free radical scavenging activity of Thai medicinal plants in osteoarthritic knee treatment.

    Science.gov (United States)

    Anuthakoengkun, Areeya; Itharat, Arunporn

    2014-08-01

    Thai medicine plants used for Osteoarthritis of knee (OA) treatment consist of twelve plants such as Crinumn asiaticum, Cleome viscosa, Drypetes roxburghii, Piper longum, Piper nigrum, Plumbago indica, Alpinia galanga, Curcuma aromatica, Globba malaccensis, Zingiber montanum, Zingiber officinale andZingiberzerumbet. They showedhighfrequency in OA formula. To investigate inhibitory effect on LPS-induced nitric oxide (NO) release from RAW264. 7 cell and free radical scavenging activity usingDPPH assay of these ethanolic plant extracts. Plant materials were extracted by maceration in 95% ethanol. Anti-inflammatory activity were tested on LPS-induced NO production. Free radical scavenging activity was performed by DPPH assay. All of ethanolic extracts exhibited potent inhibitory effect on NO release. The ethanolic extract of Z. zerumbet exhibited the highest inhibitory effect followed by Z. montanum and G. malaccensis, respectively. Except A. galanga and C. viscosa, all extracts possessed more influential than indomethacin (IC50 = 20.32±3.23 μLg/ml), a positive control. The investigation on antioxidant activity suggested that the ethanolic extracts of D. roxburghii, Z. officinale, Z. montanum, C. aromatic, A. galanga, P indica, G malaccensis, P nigrum exhibited antioxidant activity. By means ofD. roxburghii had the highest electron donating activity,followed by Z. officinale. Moreover both extracts were more effective than BHT apositive control (EC50 = 14.04±1.95 μg/ml). Thai medicinal plants had anti-inflammatory activity and could inhibit destruction of articular cartilage that corresponded to the traditional medicine and supported using these medicinal plants for OA treatment.

  11. Macrophage Migration Inhibitory Factor: Critical Role in Obesity, Insulin Resistance, and Associated Comorbidities

    Directory of Open Access Journals (Sweden)

    Robert Kleemann

    2010-01-01

    Full Text Available Obesity is associated with insulin resistance, disturbed glucose homeostasis, low grade inflammation, and comorbidities such as type 2 diabetes and cardiovascular disease. The cytokine macrophage migration inhibitory factor (MIF is an ubiquitously expressed protein that plays a crucial role in many inflammatory and autoimmune disorders. Increasing evidence suggests that MIF also controls metabolic and inflammatory processes underlying the development of metabolic pathologies associated with obesity. This is a comprehensive summary of our current knowledge on the role of MIF in obesity and obesity-associated comorbidities, based on human clinical data as well as animal models of disease.

  12. Minimum inhibitory concentration values and problematic disk break ...

    African Journals Online (AJOL)

    Latife Ä°ÅŸeri

    2015-08-08

    Aug 8, 2015 ... to tigecycline, and to test the correlation between the minimal inhibitory concentration (MIC) and ... This study was performed using 108 strains of enterococci. The .... drugs (TetA-E, TetK) from inside the bacterial cell, and ribo-.

  13. Aldose Reductase Inhibitory and Antiglycation Activities of Four ...

    African Journals Online (AJOL)

    Aldose Reductase Inhibitory and Antiglycation Activities of Four Medicinal Plant Standardized Extracts and Their Main Constituents for the Prevention of ... levels in galactosemic condition by using reverse phase high pressure liquid chromatography (RP-HPLC) and gas liquid chromatography (GLC) was determined.

  14. Inhibitory effects of Citrus hassaku extract and its flavanone glycosides on melanogenesis.

    Science.gov (United States)

    Itoh, Kimihisa; Hirata, Noriko; Masuda, Megumi; Naruto, Shunsuke; Murata, Kazuya; Wakabayashi, Keitaro; Matsuda, Hideaki

    2009-03-01

    The 50% ethanolic extract (CH-ext) obtained from the unripe fruit of Citrus hassaku exhibited significant tyrosinase inhibitory activity. The CH-ext showed antioxidant activity, such as superoxide dismutase (SOD)-like activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Activity-guided fractionation of the CH-ext indicated that flavanone glycoside-rich fractions showed potent tyrosinase inhibitory activity. Further examination revealed that the tyrosinase inhibitory activity and antioxidant activity of the CH-ext were attributable to naringin and neohesperidin, respectively. The CH-ext showed inhibition of melanogenesis without any effects on cell proliferation in cultured murine B16 melanoma cells after glucosamine exposure. The topical application of the CH-ext to the dorsal skin of brownish guinea pigs showed in vivo preventive effects against UVB-induced pigmentation.

  15. Building tolerance by dismantling synapses: inhibitory receptor signaling in natural killer cells.

    Science.gov (United States)

    Huse, Morgan; Catherine Milanoski, S; Abeyweera, Thushara P

    2013-01-01

    Cell surface receptors bearing immunotyrosine-based inhibitory motifs (ITIMs) maintain natural killer (NK) cell tolerance to normal host tissues. These receptors are difficult to analyze mechanistically because they block activating responses in a rapid and comprehensive manner. The advent of high-resolution single cell imaging techniques has enabled investigators to explore the cell biological basis of the inhibitory response. Recent studies using these approaches indicate that ITIM-containing receptors function at least in part by structurally undermining the immunological synapse between the NK cell and its target. In this review, we discuss these new advances and how they might relate to what is known about the biochemistry of inhibitory signaling in NK cells and other cell types. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  16. Catalase (KatA) Plays a Role in Protection against Anaerobic Nitric Oxide in Pseudomonas aeruginosa

    Science.gov (United States)

    Su, Shengchang; Panmanee, Warunya; Wilson, Jeffrey J.; Mahtani, Harry K.; Li, Qian; VanderWielen, Bradley D.; Makris, Thomas M.; Rogers, Melanie; McDaniel, Cameron; Lipscomb, John D.; Irvin, Randall T.; Schurr, Michael J.; Lancaster, Jack R.; Kovall, Rhett A.; Hassett, Daniel J.

    2014-01-01

    Pseudomonas aeruginosa (PA) is a common bacterial pathogen, responsible for a high incidence of nosocomial and respiratory infections. KatA is the major catalase of PA that detoxifies hydrogen peroxide (H2O2), a reactive oxygen intermediate generated during aerobic respiration. Paradoxically, PA displays elevated KatA activity under anaerobic growth conditions where the substrate of KatA, H2O2, is not produced. The aim of the present study is to elucidate the mechanism underlying this phenomenon and define the role of KatA in PA during anaerobiosis using genetic, biochemical and biophysical approaches. We demonstrated that anaerobic wild-type PAO1 cells yielded higher levels of katA transcription and expression than aerobic cells, whereas a nitrite reductase mutant ΔnirS produced ∼50% the KatA activity of PAO1, suggesting that a basal NO level was required for the increased KatA activity. We also found that transcription of the katA gene was controlled, in part, by the master anaerobic regulator, ANR. A ΔkatA mutant and a mucoid mucA22 ΔkatA bacteria demonstrated increased sensitivity to acidified nitrite (an NO generator) in anaerobic planktonic and biofilm cultures. EPR spectra of anaerobic bacteria showed that levels of dinitrosyl iron complexes (DNIC), indicators of NO stress, were increased significantly in the ΔkatA mutant, and dramatically in a ΔnorCB mutant compared to basal levels of DNIC in PAO1 and ΔnirS mutant. Expression of KatA dramatically reduced the DNIC levels in ΔnorCB mutant. We further revealed direct NO-KatA interactions in vitro using EPR, optical spectroscopy and X-ray crystallography. KatA has a 5-coordinate high spin ferric heme that binds NO without prior reduction of the heme iron (K d ∼6 μM). Collectively, we conclude that KatA is expressed to protect PA against NO generated during anaerobic respiration. We proposed that such protective effects of KatA may involve buffering of free NO when potentially toxic concentrations of

  17. Inhibitory Response Capacities of Bilateral Lower and Upper Extremities in Children with Developmental Coordination Disorder in Endogenous and Exogenous Orienting Modes

    Science.gov (United States)

    Tsai, Chia-Liang; Yu, Yi-Kai; Chen, Yung-Jung; Wu, Sheng-Kuang

    2009-01-01

    This study was designed to investigate separately the inhibitory response capacity and the lateralization effect in children with developmental coordination disorder (DCD) in the endogenous and exogenous modes of orienting attention. Children with DCD on the lower extremities (DCD-LEs), along with age-matched controls, completed four tasks that…

  18. Spikes matter for phase-locked bursting in inhibitory neurons

    Science.gov (United States)

    Jalil, Sajiya; Belykh, Igor; Shilnikov, Andrey

    2012-03-01

    We show that inhibitory networks composed of two endogenously bursting neurons can robustly display several coexistent phase-locked states in addition to stable antiphase and in-phase bursting. This work complements and enhances our recent result [Jalil, Belykh, and Shilnikov, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.81.045201 81, 045201(R) (2010)] that fast reciprocal inhibition can synchronize bursting neurons due to spike interactions. We reveal the role of spikes in generating multiple phase-locked states and demonstrate that this multistability is generic by analyzing diverse models of bursting networks with various fast inhibitory synapses; the individual cell models include the reduced leech heart interneuron, the Sherman model for pancreatic beta cells, and the Purkinje neuron model.

  19. The inhibitory effect of the various seed coating substances against rice seed borne fungi and their shelf-life during storage.

    Science.gov (United States)

    Thobunluepop, Pitipong

    2009-08-15

    Presently, chemical seed treatments are in discussion due to their directly or indirectly impacts on human health or other living organisms. They may also negatively affect the ecosystem and the food chain. In rice seeds, chemicals may cause phytotoxic effects including seed degradation. Eugenol is the main component of clove (Eugenia caryophillis) oil, which was proved to act simultaneously as bactericide, virocide and especially fungicide. The in vitro study was aimed to compare the inhibitory effect of the following seed treatment substances against seed borne fungi and their shelf-life during 12 months of storage; conventional captan (CA), chitosan-lignosulphonate polymer (CL), eugenol incorporated into chitosan-lignosulphonate polymer (E+CL) and control (CO). The obtained results of fungi inhibition were classified in three groups, which showed at first that CA treatment led to a better, i.e., longer, inhibitory effect on Alternaria padwickii, Rhizoctonia solani, Curvularia sp., Aspergillus flavus and Aspergillus niger than E+CL. Secondly, E+CL coating polymer showed the longest inhibitory effect against Bipolaris oryzae and Nigrospora oryzae compared to CA and CL coating polymer. Finally, both CA and E+CL coating polymer had non-significant difference inhibitory effect on Fusarium moniliforme. The variant of CL coating polymer for seed coating was only during the first 6 months of storage able to inhibit all species of the observed seed borne fungi, whereas CA and E+CL coating polymer were capable to inhibit most of the fungi until 9 months of storage.

  20. Inhibitory effects of Caesalpinia sappan on growth and invasion of methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Kim, Kang-Ju; Yu, Hyeon-Hee; Jeong, Seung-Il; Cha, Jung-Dan; Kim, Shin-Moo; You, Yong-Ouk

    2004-03-01

    In the present study, we investigated antimicrobial activity of Caesalpinia sappan against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and effect of Caesalpinia sappan extract on the invasion of MRSA to human mucosal fibroblasts (HMFs). Chloroform, n-butanol, methanol, and aqueous extracts of the Caesalpinia sappan showed antimicrobial activity against standard methicillin-sensitive Staphylococcus aureus (MSSA) as well as MRSA. Methanol extract of Caesalpinia sappan demonstrated a higher inhibitory activity than n-butanol, chloroform, and aqueous extracts. In the checkerboard dilution method, methanol extract of Caesalpinia sappan markedly lowered the minimal inhibitory concentrations (MICs) of ampicillin and oxacillin against MRSA. To determine whether methanol extract of Caesalpinia sappan inhibits the MRSA invasion to HMFs, the cells were treated with various sub-MIC concentrations of methanol extract and bacterial invasion was assayed. MRSA invasion was notably decreased in the presence of 20-80 microg/ml of Caesalpinia sappan extract compared to the control group. The effect of Caesalpinia sappan extract on MRSA invasion appeared dose-dependent. These results suggest that methanol extract of Caesalpinia sappan may have antimicrobial activity and the potential to restore the effectiveness of beta-lactam antibiotics against MRSA, and inhibit the MRSA invasion to HMFs.

  1. Alpha-Glucosidase Inhibitory and Antioxidant Activity of Solvent ...

    African Journals Online (AJOL)

    regression analysis. Phytochemical contents and correlation with bioactivities. Total phenolic (TP), total proanthocyanidin. (TPro), and total hydroxycinnamic acid ..... An advantage of competitive inhibitors is that their inhibitory action is reversible, thus allowing undesirable effects to be readily mitigated by decreasing the ...

  2. Identification of novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in camel milk protein hydrolysates.

    Science.gov (United States)

    Nongonierma, Alice B; Paolella, Sara; Mudgil, Priti; Maqsood, Sajid; FitzGerald, Richard J

    2018-04-01

    Nine novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (FLQY, FQLGASPY, ILDKEGIDY, ILELA, LLQLEAIR, LPVP, LQALHQGQIV, MPVQA and SPVVPF) were identified in camel milk proteins hydrolysed with trypsin. This was achieved using a sequential approach combining liquid chromatography tandem mass spectrometry (LC-MS/MS), qualitative/quantitative structure activity relationship (QSAR) and confirmatory studies with synthetic peptides. The most potent camel milk protein-derived DPP-IV inhibitory peptides, LPVP and MPVQA, had DPP-IV half maximal inhibitory concentrations (IC 50 ) of 87.0 ± 3.2 and 93.3 ± 8.0 µM, respectively. DPP-IV inhibitory peptide sequences identified within camel and bovine milk protein hydrolysates generated under the same hydrolysis conditions differ. This was linked to differences in enzyme selectivity for peptide bond cleavage of camel and bovine milk proteins as well as dissimilarities in their amino acid sequences. Camel milk proteins contain novel DPP-IV inhibitory peptides which may play a role in the regulation of glycaemia in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Isolation of proanthocyanidins from red wine, and their inhibitory effects on melanin synthesis in vitro.

    Science.gov (United States)

    Fujimaki, Takahiro; Mori, Shoko; Horikawa, Manabu; Fukui, Yuko

    2018-05-15

    The red wines made from Vitis vinifera were identified as skin-whitening effectors by using in vitro assays. OPCs in the wine were evaluated for tyrosinase activity and melanogenesis. Strong tyrosinase inhibitory activity was observed in fractions with high oligomeric proanthocyanidin (OPC) content. Among OPC dimers, a strong inhibitory effect on tyrosinase was observed with OPCs which contain (+)-catechin as an upper unit. Melanogenesis inhibitory effect was observed with OPCs which have (-)-epicatechin as upper units. Also, OPC trimers, upper and middle units joined with 4 → 8 bonds, showed stronger effects compared to trimers with 4 → 6 linkages. Interestingly, (-)-epicatechin-(4β → 8)-(-)-epicatechin 3-O-gallate, which is a unique component of grapes has potent inhibitory effects on both tyrosinase and melanogenesis. Our data provide structural information about such active compounds. These results suggest that red wines containing OPC, have high melanogenesis inhibitory effect and are supposed to have skin-whitening effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Effects of Neuromodulation on Excitatory-Inhibitory Neural Network Dynamics Depend on Network Connectivity Structure

    Science.gov (United States)

    Rich, Scott; Zochowski, Michal; Booth, Victoria

    2018-01-01

    Acetylcholine (ACh), one of the brain's most potent neuromodulators, can affect intrinsic neuron properties through blockade of an M-type potassium current. The effect of ACh on excitatory and inhibitory cells with this potassium channel modulates their membrane excitability, which in turn affects their tendency to synchronize in networks. Here, we study the resulting changes in dynamics in networks with inter-connected excitatory and inhibitory populations (E-I networks), which are ubiquitous in the brain. Utilizing biophysical models of E-I networks, we analyze how the network connectivity structure in terms of synaptic connectivity alters the influence of ACh on the generation of synchronous excitatory bursting. We investigate networks containing all combinations of excitatory and inhibitory cells with high (Type I properties) or low (Type II properties) modulatory tone. To vary network connectivity structure, we focus on the effects of the strengths of inter-connections between excitatory and inhibitory cells (E-I synapses and I-E synapses), and the strengths of intra-connections among excitatory cells (E-E synapses) and among inhibitory cells (I-I synapses). We show that the presence of ACh may or may not affect the generation of network synchrony depending on the network connectivity. Specifically, strong network inter-connectivity induces synchronous excitatory bursting regardless of the cellular propensity for synchronization, which aligns with predictions of the PING model. However, when a network's intra-connectivity dominates its inter-connectivity, the propensity for synchrony of either inhibitory or excitatory cells can determine the generation of network-wide bursting.

  5. Gain control network conditions in early sensory coding.

    Directory of Open Access Journals (Sweden)

    Eduardo Serrano

    Full Text Available Gain control is essential for the proper function of any sensory system. However, the precise mechanisms for achieving effective gain control in the brain are unknown. Based on our understanding of the existence and strength of connections in the insect olfactory system, we analyze the conditions that lead to controlled gain in a randomly connected network of excitatory and inhibitory neurons. We consider two scenarios for the variation of input into the system. In the first case, the intensity of the sensory input controls the input currents to a fixed proportion of neurons of the excitatory and inhibitory populations. In the second case, increasing intensity of the sensory stimulus will both, recruit an increasing number of neurons that receive input and change the input current that they receive. Using a mean field approximation for the network activity we derive relationships between the parameters of the network that ensure that the overall level of activity of the excitatory population remains unchanged for increasing intensity of the external stimulation. We find that, first, the main parameters that regulate network gain are the probabilities of connections from the inhibitory population to the excitatory population and of the connections within the inhibitory population. Second, we show that strict gain control is not achievable in a random network in the second case, when the input recruits an increasing number of neurons. Finally, we confirm that the gain control conditions derived from the mean field approximation are valid in simulations of firing rate models and Hodgkin-Huxley conductance based models.

  6. Cloning and expression of synthetic genes encoding angiotensin-I converting enzyme (ACE)-inhibitory bioactive peptides in Bifidobacterium pseudocatenulatum.

    Science.gov (United States)

    Losurdo, Luca; Quintieri, Laura; Caputo, Leonardo; Gallerani, Raffaele; Mayo, Baltasar; De Leo, Francesca

    2013-03-01

    A wide range of biopeptides potentially able to lower blood pressure through inhibition of the angiotensin-I converting enzyme (ACE) is produced in fermented foods by proteolytic starter cultures. This work applies a procedure based on recombinant DNA technologies for the synthesis and expression of three ACE-inhibitory peptides using a probiotic cell factory. ACE-inhibitory genes and their pro-active precursors were designed, synthesized by PCR, and cloned in Escherichia coli; after which, they were cloned into the pAM1 E. coli-bifidobacteria shuttle vector. After E. coli transformation, constructs carrying the six recombinant clones were electrotransferred into the Bifidobacterium pseudocatenulatum M115 probiotic strain. Interestingly, five of the six constructs proved to be stable. Their expression was confirmed by reverse transcription PCR. Furthermore, transformed strains displayed ACE-inhibitory activity linearly correlated to increasing amounts of cell-free cellular lysates. In particular, 50 μg of lysates from constructs pAM1-Pro-BP3 and pAM1-BP2 showed a 50% higher ACE-inhibitory activity than that of the controls. As a comparison, addition of 50 ng of Pro-BP1 and Pro-BP3 synthetic peptides to 50 μg of cell-free extracts of B. pseudocatenulatum M115 wild-type strain showed an average of 67% of ACE inhibition; this allowed estimating the amount of the peptides produced by the transformants. Engineering of bifidobacteria for the production of biopeptides is envisioned as a promising cell factory model system. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  7. Inhibitory Effects of Daiokanzoto (Da-Huang-Gan-Cao-Tang on P-Glycoprotein

    Directory of Open Access Journals (Sweden)

    Yuka Watanabe

    2012-01-01

    Full Text Available We have studied the effects of various Kampo medicines on P-glycoprotein (P-gp, a drug transporter, in vitro. The present study focused on Daiokanzoto (Da-Huang-Gan-Cao-Tang, which shows the most potent inhibitory effects on P-gp among the 50 Kampo medicines studied, and investigated the P-gp inhibitory effects of Daiokanzoto herbal ingredients (rhubarb and licorice root and their components by an ATPase assay using human P-gp membrane. Both rhubarb and licorice root significantly inhibited ATPase activity, and the effects of rhubarb were more potent than those of licorice root. The content of rhubarb in Daiokanzoto is double that in licorice root, and the inhibition patterns of Daiokanzoto and rhubarb involve both competitive and noncompetitive inhibition, suggesting that the inhibitory effects of Daiokanzoto are mainly due to rhubarb. Concerning the components of rhubarb, concentration-dependent inhibitory effects were observed for (−-catechin gallate, (−-epicatechin gallate, and (−-epigallocatechin gallate. In conclusion, rhubarb may cause changes in the drug dispositions of P-gp substrates through the inhibition of P-gp. It appears that attention should be given to the interactions between these drugs and Kampo medicines containing rhubarb as an herbal ingredient.

  8. Enzyme inhibitory and radical scavenging effects of some antidiabetic plants of Turkey

    Science.gov (United States)

    Orhan, Nilüfer; Hoçbaç, Sanem; Orhan, Didem Deliorman; Asian, Mustafa; Ergun, Fatma

    2014-01-01

    Objective(s): Ethnopharmacological field surveys demonstrated that many plants, such as Gentiana olivieri, Helichrysum graveolens, Helichrysum plicatum ssp. plicatum, Juniperus oxycedrus ssp. oxycedrus, Juniperus communis var. saxatilis, Viscum album (ssp. album, ssp. austriacum), are use