NASA Astrophysics Data System (ADS)
Makowski, J.; Chambers, D. P.; Bonin, J. A.
2012-12-01
Previous studies have suggested that ocean bottom pressure (OBP) can be used to measure the transport variability of the Antarctic Circumpolar Current (ACC). Using OBP data from the JPL ECCO model and the Gravity Recovery and Climate Experiment (GRACE), we examine the zonal transport variability of the ACC integrated between the major fronts between 2003-2010. The JPL ECCO data are used to determine average front positions for the time period studies, as well as where transport is mainly zonal. Statistical analysis will be conducted to determine the uncertainty of the GRACE observations using a simulated data set. We will also begin looking at low frequency changes and how coherent transport variability is from region to region of the ACC. Correlations with bottom pressure south of the ACC and the average basin transports will also be calculated to determine the probability of using bottom pressure south of the ACC as a means for describing the ACC dynamics and transport.
Korb, Alexander S.; Hunter, Aimee M.; Cook, Ian A.; Leuchter, Andrew F.
2009-01-01
Objective To assess whether pretreatment theta current density in the rostral anterior cingulate (rACC) and medial orbitofrontal cortex (mOFC) differentiates responders from non-responders to antidepressant medication or placebo in a double-blinded study. Methods Pretreatment EEGs were collected from 72 subjects with Major Depressive Disorder (MDD) who participated in one of three placebo-controlled trials. Subjects were randomized to receive treatment with fluoxetine, venlafaxine, or placebo. Low-resolution brain electromagnetic tomography (LORETA) was used to assess theta current density in the rACC and mOFC. Results Medication responders showed elevated rACC and mOFC theta current density compared to medication non-responders (rACC: p=0.042; mOFC: p=0.039). There was no significant difference in either brain region between placebo responders and placebo non-responders. Conclusions Theta current density in the rACC and mOFC may be useful as a biomarker for prediction of response to antidepressant medication. Significance This is the first double-blinded treatment study to examine pretreatment rACC and mOFC theta current density in relation to antidepressant response and placebo response. Results support the potential clinical utility of this approach for predicting clinical outcome to antidepressant treatments in MDD. PMID:19539524
Hagan, Cindy C.; Graham, Julia M.E.; Tait, Roger; Widmer, Barry; van Nieuwenhuizen, Adrienne O.; Ooi, Cinly; Whitaker, Kirstie J.; Simas, Tiago; Bullmore, Edward T.; Lennox, Belinda R.; Sahakian, Barbara J.; Goodyer, Ian M.; Suckling, John
2015-01-01
Objective There is little understanding of the neural system abnormalities subserving adolescent major depressive disorder (MDD). In a cross-sectional study we compare currently unipolar depressed with healthy adolescents to determine if group differences in grey matter volume (GMV) were influenced by age and illness severity. Method Structural neuroimaging was performed on 109 adolescents with current MDD and 36 healthy controls, matched for age, gender, and handedness. GMV differences were examined within the anterior cingulate cortex (ACC) and across the whole-brain. The effects of age and self-reported depressive symptoms were also examined in regions showing significant main or interaction effects. Results Whole-brain voxel based morphometry revealed no significant group differences. At the whole-brain level, both groups showed a main effect of age on GMV, although this effect was more pronounced in controls. Significant group-by-age interactions were noted: A significant regional group-by-age interaction was observed in the ACC. GMV in the ACC showed patterns of age-related differences that were dissimilar between adolescents with MDD and healthy controls. GMV in the thalamus showed an opposite pattern of age-related differences in adolescent patients compared to healthy controls. In patients, GMV in the thalamus, but not the ACC, was inversely related with self-reported depressive symptoms. Conclusions The depressed adolescent brain shows dissimilar age-related and symptom-sensitive patterns of GMV differences compared with controls. The thalamus and ACC may comprise neural markers for detecting these effects in youth. Further investigations therefore need to take both age and level of current symptoms into account when disaggregating antecedent neural vulnerabilities for MDD from the effects of MDD on the developing brain. PMID:25685707
Hagan, Cindy C; Graham, Julia M E; Tait, Roger; Widmer, Barry; van Nieuwenhuizen, Adrienne O; Ooi, Cinly; Whitaker, Kirstie J; Simas, Tiago; Bullmore, Edward T; Lennox, Belinda R; Sahakian, Barbara J; Goodyer, Ian M; Suckling, John
2015-01-01
There is little understanding of the neural system abnormalities subserving adolescent major depressive disorder (MDD). In a cross-sectional study we compare currently unipolar depressed with healthy adolescents to determine if group differences in grey matter volume (GMV) were influenced by age and illness severity. Structural neuroimaging was performed on 109 adolescents with current MDD and 36 healthy controls, matched for age, gender, and handedness. GMV differences were examined within the anterior cingulate cortex (ACC) and across the whole-brain. The effects of age and self-reported depressive symptoms were also examined in regions showing significant main or interaction effects. Whole-brain voxel based morphometry revealed no significant group differences. At the whole-brain level, both groups showed a main effect of age on GMV, although this effect was more pronounced in controls. Significant group-by-age interactions were noted: A significant regional group-by-age interaction was observed in the ACC. GMV in the ACC showed patterns of age-related differences that were dissimilar between adolescents with MDD and healthy controls. GMV in the thalamus showed an opposite pattern of age-related differences in adolescent patients compared to healthy controls. In patients, GMV in the thalamus, but not the ACC, was inversely related with self-reported depressive symptoms. The depressed adolescent brain shows dissimilar age-related and symptom-sensitive patterns of GMV differences compared with controls. The thalamus and ACC may comprise neural markers for detecting these effects in youth. Further investigations therefore need to take both age and level of current symptoms into account when disaggregating antecedent neural vulnerabilities for MDD from the effects of MDD on the developing brain.
NASA Astrophysics Data System (ADS)
Foppert, Annie; Donohue, Kathleen A.; Watts, D. Randolph; Tracey, Karen L.
2017-08-01
Eddy heat flux (EHF) is a predominant mechanism for heat transport across the zonally unbounded mean flow of the Antarctic Circumpolar Current (ACC). Observations of dynamically relevant, divergent, 4 year mean EHF in Drake Passage from the cDrake project, as well as previous studies of atmospheric and oceanic storm tracks, motivates the use of sea surface height (SSH) standard deviation, H*, as a proxy for depth-integrated, downgradient, time-mean EHF (>[EHF>¯>]) in the ACC. Statistics from the Southern Ocean State Estimate corroborate this choice and validate throughout the ACC the spatial agreement between H* and >[EHF>¯>] seen locally in Drake Passage. Eight regions of elevated >[EHF>¯>] are identified from nearly 23.5 years of satellite altimetry data. Elevated cross-front exchange usually does not span the full latitudinal width of the ACC in each region, implying a hand-off of heat between ACC fronts and frontal zones as they encounter the different >[EHF>¯>] hot spots along their circumpolar path. Integrated along circumpolar streamlines, defined by mean SSH contours, there is a convergence of
The frontal structure in Drake Passage based on the data of the section in January 2010
NASA Astrophysics Data System (ADS)
Tarakanov, Roman
2014-05-01
The frontal structure in the region of Drake Passage is investigated on the basis of data of Absolute Dynamic Topography (ADT) of French agency CLS (DT-Global-MADT-Upd product, http://aviso.oceanobs.com), and CTD- and SADCP-measurements along the hydrophysical section carried out across the passage from Smith Isl. (just to the east of the Hero F.Z.) to the Cape Horn onboard R/V "Akademik Ioffe" in January 2010. The investigation was similar to the analysis performed on the basis of data of the section carried out two weeks earlier onboard the same vessel south of Africa. Fine-jet structure of the ACC was detected in Drake Passage as well as to the south of Africa where twelve ACC jets were found. Eleven jets of the Antarctic Circumpolar Current (ACC) were revealed in Drake Passage. These were five jets of the Subantarctic Current (the band of Subantarctic Front), four jets of the South Polar Current (the band of Polar Front), and two jets of the South Antarctic Current (the band of Southern ACC Front). Two jets of the South Antarctic Current were joined in a single "super-jet" according to the velocity measurements in the section. The others were manifested by the local velocity maxima in the surface layer.
Rostral anterior cingulate cortex volume correlates with depressed mood in normal healthy children
Boes, Aaron D.; McCormick, Laurie M.; Coryell, William H.; Nopoulos, Peg
2008-01-01
BACKGROUND The rostral anterior cingulate cortex (rACC) has been implicated as a structural neural correlate of familial major depressive disorder, raising the possibility that the structure of this region may act as a biologic marker of depression vulnerability. The aim of the current study was to determine whether children and adolescents with depressive symptoms have lower rACC volume relative to those without symptoms and examine how a positive family history of depression affects this relationship. METHODS 112 normal healthy children (59 boys, 53 girls), age 7–17, without a current diagnosis or history of depression or other psychiatric illness, were recruited from the community. Mood symptoms were collected using the Pediatric Behavior Scale, a parent- and teacher-reported questionnaire. Volumetric measures of the rACC were generated using structural MRI. The relationship of depressive symptoms and rACC volume was examined. RESULTS 1) The rACC volume was significantly lower in boys with subclinical depressive symptoms compared to boys with no depressive symptoms, particularly on the left side (14.6% reduction; F = 8.90, p = .005). 2) In comparing the correlation of depressive symptoms and rACC volume in boys with a positive family history of depression to those with no family history there was a more robust negative correlation in subjects with a positive family history. 3) In girls there was not a significant association of depressive symptoms and rACC volume. CONCLUSIONS These findings lend further support to the notion that rACC structure may act as a biologic marker of vulnerability or trait-marker of depression. PMID:17916329
Kanske, Philipp; Kotz, Sonja A
2011-02-01
Coherent behavior depends on attentional control that detects and resolves conflict between opposing actions. The current functional magnetic resonance imaging study tested the hypothesis that emotion triggers attentional control to speed up conflict processing in particularly salient situations. Therefore, we presented emotionally negative and neutral words in a version of the flanker task. In response to conflict, we found activation of the dorsal anterior cingulate cortex (ACC) and of the amygdala for emotional stimuli. When emotion and conflict coincided, a region in the ventral ACC was activated, which resulted in faster conflict processing in reaction times. Emotion also increased functional connectivity between the ventral ACC and activation of the dorsal ACC and the amygdala in conflict trials. These data suggest that the ventral ACC integrates emotion and conflict and prioritizes the processing of conflict in emotional trials. This adaptive mechanism ensures rapid detection and resolution of conflict in potentially threatening situations signaled by emotional stimuli. Copyright © 2010 Wiley-Liss, Inc.
24 CFR 969.106 - ACC extension in absence of current operating subsidy.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false ACC extension in absence of current... COMPLETION OF DEBT SERVICE § 969.106 ACC extension in absence of current operating subsidy. Where Operating Subsidy under an ACC is not approved for payment during a time period which results in extension of the...
24 CFR 969.106 - ACC extension in absence of current operating subsidy.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false ACC extension in absence of current... COMPLETION OF DEBT SERVICE § 969.106 ACC extension in absence of current operating subsidy. Where Operating Subsidy under an ACC is not approved for payment during a time period which results in extension of the...
Hayman, G T; Beck von Bodman, S; Kim, H; Jiang, P; Farrand, S K
1993-01-01
The acc region, subcloned from pTiC58 of classical nopaline and agrocinopine A and B Agrobacterium tumefaciens C58, allowed agrobacteria to grow using agrocinopine B as the sole source of carbon and energy. acc is approximately 6 kb in size. It consists of at least five genes, accA through accE, as defined by complementation analysis using subcloned fragments and transposon insertion mutations of acc carried on different plasmids within the same cell. All five regions are required for agrocin 84 sensitivity, and at least four are required for agrocinopine and agrocin 84 uptake. The complementation results are consistent with the hypothesis that each of the five regions is separately transcribed. Maxicell experiments showed that the first of these genes, accA, encodes a 60-kDa protein. Analysis of osmotic shock fractions showed this protein to be located in the periplasm. The DNA sequence of the accA region revealed an open reading frame encoding a predicted polypeptide of 59,147 Da. The amino acid sequence encoded by this open reading frame is similar to the periplasmic binding proteins OppA and DppA of Escherichia coli and Salmonella typhimurium and OppA of Bacillus subtilis. Images PMID:8366042
Dissociating response conflict and error likelihood in anterior cingulate cortex.
Yeung, Nick; Nieuwenhuis, Sander
2009-11-18
Neuroimaging studies consistently report activity in anterior cingulate cortex (ACC) in conditions of high cognitive demand, leading to the view that ACC plays a crucial role in the control of cognitive processes. According to one prominent theory, the sensitivity of ACC to task difficulty reflects its role in monitoring for the occurrence of competition, or "conflict," between responses to signal the need for increased cognitive control. However, a contrasting theory proposes that ACC is the recipient rather than source of monitoring signals, and that ACC activity observed in relation to task demand reflects the role of this region in learning about the likelihood of errors. Response conflict and error likelihood are typically confounded, making the theories difficult to distinguish empirically. The present research therefore used detailed computational simulations to derive contrasting predictions regarding ACC activity and error rate as a function of response speed. The simulations demonstrated a clear dissociation between conflict and error likelihood: fast response trials are associated with low conflict but high error likelihood, whereas slow response trials show the opposite pattern. Using the N2 component as an index of ACC activity, an EEG study demonstrated that when conflict and error likelihood are dissociated in this way, ACC activity tracks conflict and is negatively correlated with error likelihood. These findings support the conflict-monitoring theory and suggest that, in speeded decision tasks, ACC activity reflects current task demands rather than the retrospective coding of past performance.
NASA Astrophysics Data System (ADS)
Provost, C.; Artana, C.; Ferrari, R.; Koenig, Z.; Saraceno, M.; Piola, A. R.
2016-12-01
The Malvinas Current (MC) is an offshoot of the Antarctic Circumpolar Current (ACC). Downstream of Drake Passage, the northern fronts of the ACC veer northward, cross over the North Scotia Ridge (NSR) and the Malvinas Plateau and enter the Argentine Basin. We investigate the variations of the MC circulation between the NSR and 41°S and their possible relations with the ACC circulation using data from Argo floats and satellite altimetry. The data depict meandering and eddy-shedding of the northern ACC jets as they cross the NSR. The satellite fields (altimetry and high resolution sea surface temperature images) show that these eddies are trapped, break down and dissipate over the Malvinas Plateau, suggesting that this region is a hot spot for dissipation of mesoscale variability. Variations of sea level anomalies (SLA) across the NSR do not impact the MC further north, except for intra-seasonal variability associated with coastal trapped waves. Altimetry and float trajectories show events during which a large fraction of the MC is cut off from the ACC. During these blocking events, the MC does not collapse as a robust cyclonic cell is established to the north of the cut-off. The MC becomes the western boundary current of the cell and small cyclonic eddies locally reinforce the circulation. Blocking events at around 48.5°S are a recurrent feature of the MC circulation. Over the 23 year altimetry record, we detected 26 events during which the MC surface transport at 48.5°S was reduced to less than half its long term mean. Blocking events last from 10 to 35 days and do not present any significant trend. These events were tracked back to positive SLA that built up over the Argentine Abyssal Plain.
Malvinas Current variability from Argo floats and satellite altimetry
NASA Astrophysics Data System (ADS)
Artana, Camila; Ferrari, Ramiro; Koenig, Zoé; Saraceno, Martin; Piola, Alberto R.; Provost, Christine
2016-07-01
The Malvinas Current (MC) is an offshoot of the Antarctic Circumpolar Current (ACC). Downstream of Drake Passage, the northern fronts of the ACC veer northward, cross over the North Scotia Ridge (NSR) and the Malvinas Plateau, and enter the Argentine Basin. We investigate the variations of the MC circulation between the NSR and 41°S and their possible relations with the ACC circulation using data from Argo floats and satellite altimetry. The data depict meandering and eddy shedding of the northern ACC jets as they cross the NSR. The altimetry fields show that these eddies are trapped, break down, and dissipate over the Malvinas Plateau, suggesting that this region is a hot spot for dissipation of mesoscale variability. Variations of sea level anomalies (SLA) across the NSR do not impact the MC further north, except for intra-seasonal variability associated with coastal trapped waves. Altimetry and float trajectories show events during which a large fraction of the MC is cut off from the ACC. Blocking events at around 48.5°S are a recurrent feature of the MC circulation. Over the 23 year altimetry record, we detected 26 events during which the MC surface transport at 48.5°S was reduced to less than half its long-term mean. Blocking events last from 10 to 35 days and do not present any significant trend. These events were tracked back to positive SLA that built up over the Argentine Abyssal Plain. Future work is needed to understand the processes responsible for these blocking events.
Liu, Yi; Du, Lian; Li, Yongmei; Liu, Haixia; Zhao, Wenjing; Liu, Dan; Zeng, Jinkun; Li, Xingbao; Fu, Yixiao; Qiu, Haitang; Li, Xirong; Qiu, Tian; Hu, Hua; Meng, Huaqing; Luo, Qinghua
2015-01-01
Abstract The mechanisms underlying the effects of electroconvulsive therapy (ECT) in major depressive disorder (MDD) are not fully understood. Resting-state functional magnetic resonance imaging (rs-fMRI) is a new tool to study the effects of brain stimulation interventions, particularly ECT. The authors aim to investigate the mechanisms of ECT in MDD by rs-fMRI. They used rs-fMRI to measure functional changes in the brain of first-episode, treatment-naive MDD patients (n = 23) immediately before and then following 8 ECT sessions (brief-pulse square-wave apparatus, bitemporal). They also computed voxel-wise amplitude of low-frequency fluctuation (ALFF) as a measure of regional brain activity and selected the left subgenual anterior cingulate cortex (sgACC) to evaluate functional connectivity between the sgACC and other brain regions. Increased regional brain activity measured by ALFF mainly in the left sgACC following ECT. Functional connectivity of the left sgACC increased in the ipsilateral parahippocampal gyrus, pregenual ACC, contralateral middle temporal pole, and orbitofrontal cortex. Importantly, reduction in depressive symptoms were negatively correlated with increased ALFF in the left sgACC and left hippocampus, and with distant functional connectivity between the left sgACC and contralateral middle temporal pole. That is, across subjects, as depression improved, regional brain activity in sgACC and its functional connectivity increased in the brain. Eight ECT sessions in MDD patients modulated activity in the sgACC and its networks. The antidepressant effects of ECT were negatively correlated with sgACC brain activity and connectivity. These findings suggest that sgACC-associated prefrontal-limbic structures are associated with the therapeutic effects of ECT in MDD. PMID:26559309
Weber, Matthew J; Messing, Samuel B; Rao, Hengyi; Detre, John A; Thompson-Schill, Sharon L
2014-08-01
Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique used both experimentally and therapeutically to modulate regional brain function. However, few studies have directly measured the aftereffects of tDCS on brain activity or examined changes in task-related brain activity consequent to prefrontal tDCS. To investigate the neural effects of tDCS, we collected fMRI data from 22 human subjects, both at rest and while performing the Balloon Analog Risk Task (BART), before and after true or sham transcranial direct current stimulation. TDCS decreased resting blood perfusion in orbitofrontal cortex and the right caudate and increased task-related activity in the right dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) in response to losses but not wins or increasing risk. Network analysis showed that whole-brain connectivity of the right ACC correlated positively with the number of pumps subjects were willing to make on the BART, and that tDCS reduced connectivity between the right ACC and the rest of the brain. Whole-brain connectivity of the right DLPFC also correlated negatively with pumps on the BART, as prior literature would suggest. Our results suggest that tDCS can alter activation and connectivity in regions distal to the electrodes. Copyright © 2014 Wiley Periodicals, Inc.
Management of adrenal cancer: a 2013 update.
Terzolo, M; Daffara, F; Ardito, A; Zaggia, B; Basile, V; Ferrari, L; Berruti, A
2014-03-01
Adrenocortical carcinoma (ACC) is a devastating tumor for either patients or their families because of short life expectancy and severe impact on quality of life. Due to the rarity of ACC, with a reported annual incidence of 0.5-2 cases per million population, progress in the development of treatment options beyond surgery has been limited. Up to now, no personalized approach of ACC therapy has emerged, apart from plasma level-guided mitotane therapy, and no simple targetable molecular event has been identified from preclinical studies. Complete surgical removal of ACC is the only potentially curative approach and has the most important impact on patient’s prognosis. Despite the limits of the available evidence, adjuvant mitotane therapy is currently recommended in many expert centers whenever the patients present an elevated risk of recurrence. The management of patients with recurrent and metastatic disease is challenging and the prognosis is often poor. Mitotane monotherapy is indicated in the management of patients with a low tumor burden and/or more indolent disease while patients whose disease show an aggressive behavior need cytotoxic chemotherapy. The treatment of patients with advanced ACC may include loco-regional approaches such as surgery and radiofrequency ablation in addition to systemic therapies. The present review provides an updated overview of the management of ACC patients following surgery and of the management of ACC patients with advanced disease.
Identification of acid-sensing ion channels in adenoid cystic carcinomas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye Jinhai; Department of Oral and Maxillofacial Surgery, School of Stomatology, Nanjing Medical University, Research Institute of Stomatology, Nanjing 210029; Gao Jun
2007-04-20
Tissue acidosis is an important feature of tumor. The response of adenoid cystic carcinoma (ACC) cells to acidic solution was studied using whole-cell patch-clamp recording in the current study. An inward, amiloride-sensitive Na{sup +} current was identified in cultured ACC-2 cells while not in normal human salivary gland epithelial cells. Electrophysiological and pharmacological properties of the currents suggest that heteromeric acid-sensing ion channels (ASICs) containing 2a and 3 may be responsible for the proton-induced currents in the majority of ACC-2 cells. Consistent with it, analyses of RT-PCR and Western blotting demonstrated the presences of ASIC2a and 3 in ACC-2 cells.more » Furthermore, we observed the enhanced expression of ASIC2a and 3 in the sample of ACC tissues. These results indicate that the functional expression of ASICs is characteristic feature of ACC cells.« less
Frontal beta-theta network during REM sleep
Vijayan, Sujith; Lepage, Kyle Q; Kopell, Nancy J; Cash, Sydney S
2017-01-01
We lack detailed knowledge about the spatio-temporal physiological signatures of REM sleep, especially in humans. By analyzing intracranial electrode data from humans, we demonstrate for the first time that there are prominent beta (15–35 Hz) and theta (4–8 Hz) oscillations in both the anterior cingulate cortex (ACC) and the DLPFC during REM sleep. We further show that these theta and beta activities in the ACC and the DLPFC, two relatively distant but reciprocally connected regions, are coherent. These findings suggest that, counter to current prevailing thought, the DLPFC is active during REM sleep and likely interacting with other areas. Since the DLPFC and the ACC are implicated in memory and emotional regulation, and the ACC has motor areas and is thought to be important for error detection, the dialogue between these two areas could play a role in the regulation of emotions and in procedural motor and emotional memory consolidation. DOI: http://dx.doi.org/10.7554/eLife.18894.001 PMID:28121613
Impact of the Agulhas Return Current on the glacial Subantarctic region in the South Indian Ocean
NASA Astrophysics Data System (ADS)
Ikehara, M.; Crosta, X.; Manoj, M. C.
2017-12-01
The Southern Ocean has played an important role in the evolution of the global climate system. The Southern Ocean circulation is dominated by the Antarctic Circumpolar Current (ACC), the world's longest and largest current system. Sea ice coverage on sea surface strongly affects the climate of the Southern Hemisphere through its impacts on the energy and gas budget, on the atmospheric circulation, on the hydrological cycle, and on the biological productivity. The Agulhas Return Current (ARC) originates from the Agulhas Current, the major western boundary current in the Indian Ocean, and transports heat from subtropical to subantarctic region. It's thought that the Agulhas leakage from the Indian Ocean to the Atlantic was reduced for the last glacial due to a northward shift of the westerlies and ACC, however, there are still unknown yet how the ARC was responded to the reduced Agulhas leakage. A piston core DCR-1PC was collected from the Del Caño Rise (46°S, 44°E, 2632m), Indian sector of the Southern Ocean. Core site located in the Subantarctic region between the Subtropical Front (STF) and Subantarctic Front (SAF). Age model of the core was established by radiocarbon dating of planktic foraminifer Globorotalia bulloides and oxygen isotope stratigraphy of benthic foraminifers Cibicidoides wuellerstorfi and Melonis bareelanus. Sediment of DCR-1PC show the cyclic changes of diatom/carbonate ooze sedimentation corresponding to Southern Ocean fronts' migrations on glacial-interglacial timescales. Records of ice-rafted debris (IRD) and oxygen isotope in planktic foraminfer G. bulloides suggest that the melting of sea ice was significantly increased during the last glacial maximum (LGM) in the Subantarctic surface water. Diatom assemblage based summer SST also shows the relative warmer condition in the Subantarctic during the LGM. These results might be explained by the strong influence of the Agulhas Return Current during the LGM in the Subantarctic. The reduced Agulhas leakage due to a northward shift of the westerlies and ACC impacted significantly on sea ice melting in the glacial Subantarctic region in the South Indian Ocean.
Cui, Long-Biao; Liu, Jian; Wang, Liu-Xian; Li, Chen; Xi, Yi-Bin; Guo, Fan; Wang, Hua-Ning; Zhang, Lin-Chuan; Liu, Wen-Ming; He, Hong; Tian, Ping; Yin, Hong; Lu, Hongbing
2015-01-01
Understanding the neural basis of schizophrenia (SZ) is important for shedding light on the neurobiological mechanisms underlying this mental disorder. Structural and functional alterations in the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), hippocampus, and medial prefrontal cortex (MPFC) have been implicated in the neurobiology of SZ. However, the effective connectivity among them in SZ remains unclear. The current study investigated how neuronal pathways involving these regions were affected in first-episode SZ using functional magnetic resonance imaging (fMRI). Forty-nine patients with a first-episode of psychosis and diagnosis of SZ—according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision—were studied. Fifty healthy controls (HCs) were included for comparison. All subjects underwent resting state fMRI. We used spectral dynamic causal modeling (DCM) to estimate directed connections among the bilateral ACC, DLPFC, hippocampus, and MPFC. We characterized the differences using Bayesian parameter averaging (BPA) in addition to classical inference (t-test). In addition to common effective connectivity in these two groups, HCs displayed widespread significant connections predominantly involved in ACC not detected in SZ patients, but SZ showed few connections. Based on BPA results, SZ patients exhibited anterior cingulate cortico-prefrontal-hippocampal hyperconnectivity, as well as ACC-related and hippocampal-dorsolateral prefrontal-medial prefrontal hypoconnectivity. In summary, spectral DCM revealed the pattern of effective connectivity involving ACC in patients with first-episode SZ. This study provides a potential link between SZ and dysfunction of ACC, creating an ideal situation to associate mechanisms behind SZ with aberrant connectivity among these cognition and emotion-related regions. PMID:26578933
Can we observe the fronts of the Antarctic Circumpolar Current using GRACE OBP?
NASA Astrophysics Data System (ADS)
Makowski, J.; Chambers, D. P.; Bonin, J. A.
2014-12-01
The Antarctic Circumpolar Current (ACC) and the Southern Ocean remains one of the most undersampled regions of the world's oceans. The ACC is comprised of four major fronts: the Sub-Tropical Front (STF), the Polar Front (PF), the Sub-Antarctic Front (SAF), and the Southern ACC Front (SACCF). These were initially observed individually from repeat hydrographic sections and their approximate locations globally have been quantified using all available temperature data from the World Ocean and Climate Experiment (WOCE). More recent studies based on satellite altimetry have found that the front positions are more dynamic and have shifted south by up to 1° on average since 1993. Using ocean bottom pressure (OBP) data from the current Gravity Recovery and Climate Experiment (GRACE) we have measured integrated transport variability of the ACC south of Australia. However, differentiation of variability of specific fronts has been impossible due to the necessary smoothing required to reduce noise and correlated errors in the measurements. The future GRACE Follow-on (GFO) mission and the post 2020 GRACE-II mission are expected to produce higher resolution gravity fields with a monthly temporal resolution. Here, we study the resolution and error characteristics of GRACE gravity data that would be required to resolve variations in the front locations and transport. To do this, we utilize output from a high-resolution model of the Southern Ocean, hydrology models, and ice sheet surface mass balance models; add various amounts of random and correlated errors that may be expected from GFO and GRACE-II; and quantify requirements needed for future satellite gravity missions to resolve variations along the ACC fronts.
Cullen, Patrick K; Gilman, T Lee; Winiecki, Patrick; Riccio, David C; Jasnow, Aaron M
2015-10-01
Memories for context become less specific with time resulting in animals generalizing fear from training contexts to novel contexts. Though much attention has been given to the neural structures that underlie the long-term consolidation of a context fear memory, very little is known about the mechanisms responsible for the increase in fear generalization that occurs as the memory ages. Here, we examine the neural pattern of activation underlying the expression of a generalized context fear memory in male C57BL/6J mice. Animals were context fear conditioned and tested for fear in either the training context or a novel context at recent and remote time points. Animals were sacrificed and fluorescent in situ hybridization was performed to assay neural activation. Our results demonstrate activity of the prelimbic, infralimbic, and anterior cingulate (ACC) cortices as well as the ventral hippocampus (vHPC) underlie expression of a generalized fear memory. To verify the involvement of the ACC and vHPC in the expression of a generalized fear memory, animals were context fear conditioned and infused with 4% lidocaine into the ACC, dHPC, or vHPC prior to retrieval to temporarily inactivate these structures. The results demonstrate that activity of the ACC and vHPC is required for the expression of a generalized fear memory, as inactivation of these regions returned the memory to a contextually precise form. Current theories of time-dependent generalization of contextual memories do not predict involvement of the vHPC. Our data suggest a novel role of this region in generalized memory, which should be incorporated into current theories of time-dependent memory generalization. We also show that the dorsal hippocampus plays a prolonged role in contextually precise memories. Our findings suggest a possible interaction between the ACC and vHPC controls the expression of fear generalization. Copyright © 2015 Elsevier Inc. All rights reserved.
Li, S J; Cronan, J E
1993-01-01
Acetyl coenzyme A (CoA) carboxylase catalyzes the synthesis of malonyl-CoA, the first intermediate of fatty acid synthesis. The Escherichia coli enzyme is encoded by four subunits located at three different positions on the E. coli chromosome. The accBC genes lie in a small operon at min 72, whereas accA and accD are located at min 4.3 and 50, respectively. We examined the expression of the genes that encode the E. coli acetyl-CoA carboxylase subunits (accA, accBC, and accD) under a variety of growth conditions by quantitative Northern (RNA) blot analysis. We found a direct correlation between the levels of transcription of the acc genes and the rate of cellular growth. Consistent results were also obtained upon nutritional upshift and downshift experiments and upon dilution of stationary-phase cultures into fresh media. We also determined the 5' end of the accA and accD mRNAs by primer extension and did transcriptional fusion analysis of the previously reported accBC promoter. Several interesting features were found in the promoter regions of these genes, including a bent DNA sequence and an open reading frame within the unusually long leader mRNA of the accBC operon, potential stem-loop structures in the accA and accD mRNA leader regions, and a stretch of GC-rich sequences followed by AT-rich sequences common to all three promoters. In addition, both accA and accD are located in complex gene clusters. For example, the accA promoter was localized within the upstream polC gene (which encodes the DNA polymerase III catalytic subunit), suggesting that additional regulatory mechanisms exist. Images PMID:7678242
Origin, signature and palaeoclimatic influence of the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Barker, P. F.; Thomas, E.
2004-06-01
The Antarctic Circumpolar Current (ACC) is today the strongest current in the world's ocean, with a significant influence on global climate. Its assumed history and influence on palaeoclimate, while almost certainly equally profound, are here called into question. In this paper, we review 30 years of accumulated data, interpretation and speculation about the ACC, deriving mainly from DSDP and ODP drilling in the Southern Ocean. For most of this time, a conventional view of ACC development, signature and influence has held sway among palaeoceanographers and marine geologists. In this view, the ACC began at about 34 Ma, close to the Eocene-Oligocene boundary, the time of onset of significant Antarctic glaciation and the time of creation of a deep-water gap (Tasmanian Seaway) between Australia and Antarctica as the South Tasman Rise separated from North Victoria Land. This is the "smoking gun" of synchroneity. The Southern Ocean sediment record shows a latest Eocene development and subsequent geographic expansion of a siliceous biofacies, its northern limit taken to indicate the palaeo-position of the ACC axis. In addition, the ACC was considered to have caused Antarctic glaciation by isolating the continent within a cold-water annulus, reducing north-south heat transport. A different (and later) date for Antarctic-South American opening ("Drake Passage") was proposed, but the timing of ACC onset there was disputed, and the simple story survived. Recent developments, however, call it into question. Modern physical oceanography shows that all or most of present-day ACC transport is confined to narrow jets within deep-reaching circumpolar fronts, and numerical modelling has suggested that a steady reduction in greenhouse gas concentration through the Cenozoic could cause Antarctic glaciation, with or without a contribution from ocean circulation change. The rapidity of Antarctic glacial onset at the Eocene-Oligocene boundary and coeval creation of a deep-water gap south of Tasmania both survive but, in light of the new information, the presence of a siliceous biofacies cannot be claimed as evidence of the existence of a continuous, deep-reaching oceanic front and therefore of an ACC, and the possibility arises that cool and cold sea-surface temperatures were effects of Antarctic glaciation rather than evidence of a major contributor to its cause. In considering future work, we emphasise the importance of additional information from ancillary fields—better definition of the necessary and sufficient properties of oceanic fronts, additional determinations of Cenozoic atmospheric pCO 2 and further developments in models of Antarctic glaciation—but also suggest the way forward in marine geology. Our knowledge of the development and palaeoclimatic significance of the ACC will be best served by grain-size studies of bottom current strength at selected locations, and geochemical or mineralogical studies of clays and IRD as a way of examining provenance and therefore surface and bottom current directions and the existence of interocean connections. Studies of biogenic assemblages within the same sediments may be able to recover a value for the many such studies undertaken in the past and interpreted, probably erroneously, as evidence for an ACC. Mainly in view of the timing uncertainties, we propose the region south of South America as the best initial focus of future investigation.
Canterberry, Melanie; Hanlon, Colleen A; Hartwell, Karen J; Li, Xingbao; Owens, Max; LeMatty, Todd; Prisciandaro, James J; Borckardt, Jeffrey; Saladin, Michael E; Brady, Kathleen T; George, Mark S
2013-12-01
Neurofeedback delivered via real-time functional magnetic resonance imaging (rtfMRI) is a promising therapeutic technique being explored to facilitate self-regulation of craving in nicotine-dependent cigarette smokers. The current study examined the role of nicotine-dependence severity and the efficacy of multiple visits of neurofeedback from a single region of interest (ROI) in the anterior cingulate cortex (ACC) on craving reduction. Nine nicotine-dependent cigarette smokers participated in three rtfMRI visits that examined cue-induced craving and brain activation. Severity of nicotine dependence was assessed with the Fagerström Test for Nicotine Dependence. When viewing smoking-related images with instructions to "crave," patient-tailored ROIs were generated in the vicinity of the ACC. Activity levels from the ROI were fed back while participants viewed smoking cues with the instruction to reduce craving. Neurofeedback from a single ROI in the ACC led to consistent decreases in self-reported craving and activation in the ACC across the three visits. Dependence severity predicted response to neurofeedback at Visit 3. This study builds upon previous rtfMRI studies on the regulation of nicotine craving in demonstrating that feedback from the ACC can reduce activation to smoking cues across three separate visits. Individuals with lower nicotine-dependence severity were more successful in reducing ACC activation over time. These data highlight the need to consider dependence severity in developing more individualized neurofeedback methods.
Ramirez-Mahaluf, Juan P.; Roxin, Alexander; Mayberg, Helen S.; Compte, Albert
2017-01-01
Abstract Major depression disease (MDD) is associated with the dysfunction of multinode brain networks. However, converging evidence implicates the reciprocal interaction between midline limbic regions (typified by the ventral anterior cingulate cortex, vACC) and the dorso-lateral prefrontal cortex (dlPFC), reflecting interactions between emotions and cognition. Furthermore, growing evidence suggests a role for abnormal glutamate metabolism in the vACC, while serotonergic treatments (selective serotonin reuptake inhibitor, SSRI) effective for many patients implicate the serotonin system. Currently, no mechanistic framework describes how network dynamics, glutamate, and serotonin interact to explain MDD symptoms and treatments. Here, we built a biophysical computational model of 2 areas (vACC and dlPFC) that can switch between emotional and cognitive processing. MDD networks were simulated by slowing glutamate decay in vACC and demonstrated sustained vACC activation. This hyperactivity was not suppressed by concurrent dlPFC activation and interfered with expected dlPFC responses to cognitive signals, mimicking cognitive dysfunction seen in MDD. Simulation of clinical treatments (SSRI or deep brain stimulation) counteracted this aberrant vACC activity. Theta and beta/gamma oscillations correlated with network function, representing markers of switch-like operation in the network. The model shows how glutamate dysregulation can cause aberrant brain dynamics, respond to treatments, and be reflected in EEG rhythms as biomarkers of MDD. PMID:26514163
USDA-ARS?s Scientific Manuscript database
Tepary bean (Phaseolus acutifolius A. Gray), a truly Native American crop, is a short life-cycle annual desert legume indigenous to northwestern Mexico and the southwestern USA and is considered drought and heat tolerant. The Western Regional Plant Introduction Station currently maintains 211 acce...
Dysfunctional insular connectivity during reward prediction in patients with first-episode psychosis
Schmidt, André; Palaniyappan, Lena; Smieskova, Renata; Simon, Andor; Riecher-Rössler, Anita; Lang, Undine E.; Fusar-Poli, Paolo; McGuire, Philip; Borgwardt, Stefan J.
2016-01-01
Background Increasing evidence indicates that psychosis is associated with abnormal reward processing. Imaging studies in patients with first-episode psychosis (FEP) have revealed reduced activity in diverse brain regions, including the ventral striatum, insula and anterior cingulate cortex (ACC), during reward prediction. However, whether these reductions in local brain activity are due to altered connectivity has rarely been explored. Methods We applied dynamic causal modelling and Bayesian model selection to fMRI data during the Salience Attribution Task to investigate whether patients with FEP showed abnormal modulation of connectivity between the ventral striatum, insula and ACC induced by rewarding cues and whether these changes were related to positive psychotic symptoms and atypical antipsychotic medication. Results The model including reward-induced modulation of insula–ACC connectivity was the best fitting model in each group. Compared with healthy controls (n = 19), patients with FEP (n = 29) revealed reduced right insula–ACC connectivity. After subdividing patients according to current antipsychotic medication, we found that the reduced insula–ACC connectivity relative to healthy controls was observed only in untreated patients (n = 17), not in patients treated with antipsychotics (n = 12), and that it correlated negatively with unusual thought content in untreated patients with FEP. Limitations The modest sample size of untreated patients with FEP was a limitation of our study. Conclusion This study indicates that insula–ACC connectivity during reward prediction is reduced in untreated patients with FEP and related to the formation of positive psychotic symptoms. Our study further suggests that atypical antipsychotics may reverse connectivity between the insula and the ACC during reward prediction. PMID:26854756
Common and Distinct Neural Mechanisms of Attentional Switching and Response Conflict
Kim, Chobok; Johnson, Nathan F.; Gold, Brian T.
2012-01-01
The human capacities for overcoming prepotent actions and flexibly switching between tasks represent cornerstones of cognitive control. Functional neuroimaging has implicated a diverse set of brain regions contributing to each of these cognitive control processes. However, the extent to which attentional switching and response conflict draw on shared or distinct neural mechanisms remains unclear. The current study examined the neural correlates of response conflict and attentional switching using event-related functional magnetic resonance imaging (fMRI) and a fully randomized 2×2 design. We manipulated an arrow-word version of the Stroop task to measure conflict and switching in the context of a single task decision, in response to a common set of stimuli. Under these common conditions, both behavioral and imaging data showed significant main effects of conflict and switching but no interaction. However, conjunction analyses identified frontal regions involved in both switching and response conflict, including the dorsal anterior cingulate cortex (dACC) and left inferior frontal junction. In addition, connectivity analyses demonstrated task-dependent functional connectivity patterns between dACC and inferior temporal cortex for attentional switching and between dACC and posterior parietal cortex for response conflict. These results suggest that the brain makes use of shared frontal regions, but can dynamically modulate the connectivity patterns of some of those regions, to deal with attentional switching and response conflict. PMID:22750124
Common and distinct neural mechanisms of attentional switching and response conflict.
Kim, Chobok; Johnson, Nathan F; Gold, Brian T
2012-08-21
The human capacities for overcoming prepotent actions and flexibly switching between tasks represent cornerstones of cognitive control. Functional neuroimaging has implicated a diverse set of brain regions contributing to each of these cognitive control processes. However, the extent to which attentional switching and response conflict draw on shared or distinct neural mechanisms remains unclear. The current study examined the neural correlates of response conflict and attentional switching using event-related functional magnetic resonance imaging (fMRI) and a fully randomized 2×2 design. We manipulated an arrow-word version of the Stroop task to measure conflict and switching in the context of a single task decision, in response to a common set of stimuli. Under these common conditions, both behavioral and imaging data showed significant main effects of conflict and switching but no interaction. However, conjunction analyses identified frontal regions involved in both switching and response conflict, including the dorsal anterior cingulate cortex (dACC) and left inferior frontal junction. In addition, connectivity analyses demonstrated task-dependent functional connectivity patterns between dACC and inferior temporal cortex for attentional switching and between dACC and posterior parietal cortex for response conflict. These results suggest that the brain makes use of shared frontal regions, but can dynamically modulate the connectivity patterns of some of those regions, to deal with attentional switching and response conflict. Copyright © 2012 Elsevier B.V. All rights reserved.
Ristow, Inka; Li, Meng; Colic, Lejla; Marr, Vanessa; Födisch, Carina; von Düring, Felicia; Schiltz, Kolja; Drumkova, Krasimira; Witzel, Joachim; Walter, Henrik; Beier, Klaus; Kruger, Tillmann H C; Ponseti, Jorge; Schiffer, Boris; Walter, Martin
2018-01-01
A pedophilic disorder is characterised by abnormal sexual urges towards prepubescent children. Child abusive behavior is frequently a result of lack of behavioral inhibition and current treatment options entail, next to suppressing unchangeable sexual orientation, measures to increase cognitive and attentional control. We tested, if in brain regions subserving attentional control of behavior and perception of salient stimuli, such inhibition deficit can be observed also on the level of inhibitory neurotransmitters. We measured GABA concentration in the dorsal anterior cingulate cortex (dACC) and in a control region, the pregenual anterior cingulate cortex (pgACC) in pedophilic sex offenders ( N = 13) and matched controls ( N = 13) using a 7 Tesla STEAM magnetic resonance spectroscopy (MRS). In dACC but not in the control region pedophilic sex offenders showed reduced GABA/Cr concentrations compared to healthy controls. The reduction was robust after controlling for potential influence of age and gray matter proportion within the MRS voxel ( p < 0.04). Importantly, reduced GABA/Cr in patients was correlated with lower self-control measured with the Barratt Impulsiveness Scale (p = 0.028, r = -0.689). In a region related to cognitive control and salience mapping, pedophilic sex offenders showed reduction of the inhibitory neurotransmitter GABA which may be seen as a neuronal correlate of inhibition and behavioral control.
Chae, Young Kwang; Chung, Su Yun; Davis, Andrew A.; Carneiro, Benedito A.; Chandra, Sunandana; Kaplan, Jason; Kalyan, Aparna; Giles, Francis J.
2015-01-01
Adenoid cystic carcinoma (ACC) is a rare cancer with high potential for recurrence and metastasis. Efficacy of current treatment options, particularly for advanced disease, is very limited. Recent whole genome and exome sequencing has dramatically improved our understanding of ACC pathogenesis. A balanced translocation resulting in the MYB-NFIB fusion gene appears to be a fundamental signature of ACC. In addition, sequencing has identified a number of other driver genes mutated in downstream pathways common to other well-studied cancers. Overexpression of oncogenic proteins involved in cell growth, adhesion, cell cycle regulation, and angiogenesis are also present in ACC. Collectively, studies have identified genes and proteins for targeted, mechanism-based, therapies based on tumor phenotypes, as opposed to nonspecific cytotoxic agents. In addition, although few studies in ACC currently exist, immunotherapy may also hold promise. Better genetic understanding will enable treatment with novel targeted agents and initial exploration of immune-based therapies with the goal of improving outcomes for patients with ACC. PMID:26359351
Distinct Regions within Medial Prefrontal Cortex Process Pain and Cognition
Jahn, Andrew; Nee, Derek Evan; Alexander, William H.
2016-01-01
Neuroimaging studies of the medial prefrontal cortex (mPFC) suggest that the dorsal anterior cingulate cortex (dACC) region is responsive to a wide variety of stimuli and psychological states, such as pain, cognitive control, and prediction error (PE). In contrast, a recent meta-analysis argues that the dACC is selective for pain, whereas the supplementary motor area (SMA) and pre-SMA are specifically associated with higher-level cognitive processes (Lieberman and Eisenberger, 2015). To empirically test this claim, we manipulated effects of pain, conflict, and PE in a single experiment using human subjects. We observed a robust dorsal-ventral dissociation within the mPFC with cognitive effects of PE and conflict overlapping dorsally and pain localized more ventrally. Classification of subjects based on the presence or absence of a paracingulate sulcus showed that PE effects extended across the dorsal area of the dACC and into the pre-SMA. These results begin to resolve recent controversies by showing the following: (1) the mPFC includes dissociable regions for pain and cognitive processing; and (2) meta-analyses are correct in localizing cognitive effects to the dACC, although these effects extend to the pre-SMA as well. These results both provide evidence distinguishing between different theories of mPFC function and highlight the importance of taking individual anatomical variability into account when conducting empirical studies of the mPFC. SIGNIFICANCE STATEMENT Decades of neuroimaging research have shown the mPFC to represent a wide variety of stimulus processing and cognitive states. However, recently it has been argued whether distinct regions of the mPFC separately process pain and cognitive phenomena. To address this controversy, this study directly compared pain and cognitive processes within subjects. We found a double dissociation within the mPFC with pain localized ventral to the cingulate sulcus and cognitive effects localized more dorsally within the dACC and spreading into the pre-supplementary motor area. This provides empirical evidence to help resolve the current debate about the functional architecture of the mPFC. PMID:27807031
Medial frontal white and gray matter contributions to general intelligence.
Ohtani, Toshiyuki; Nestor, Paul G; Bouix, Sylvain; Saito, Yukiko; Hosokawa, Taiga; Kubicki, Marek
2014-01-01
The medial orbitofrontal cortex (mOFC) and rostral anterior cingulate cortex (rACC) are part of a wider neural network that plays an important role in general intelligence and executive function. We used structural brain imaging to quantify magnetic resonance gray matter volume and diffusion tensor white matter integrity of the mOFC-rACC network in 26 healthy participants who also completed neuropsychological tests of intellectual abilities and executive function. Stochastic tractography, the most effective Diffusion Tensor Imaging method for examining white matter connections between adjacent gray matter regions, was employed to assess the integrity of mOFC-rACC pathways. Fractional anisotropy (FA), which reflects the integrity of white matter connections, was calculated. Results indicated that higher intelligence correlated with greater gray matter volumes for both mOFC and rACC, as well as with increased FA for left posterior mOFC-rACC connectivity. Hierarchical regression analyses revealed that DTI-derived FA of left posterior mOFC-rACC uniquely accounted for 29%-34% of the variance in IQ, in comparison to 11%-16% uniquely explained by gray matter volume of the left rACC. Together, left rACC gray matter volume and white matter connectivity between left posterior mOFC and rACC accounted for up to 50% of the variance in general intelligence. This study is to our knowledge the first to examine white matter connectivity between OFC and ACC, two gray matter regions of interests that are very close in physical proximity, and underscores the important independent contributions of variations in rACC gray matter volume and mOFC-rACC white matter connectivity to individual differences in general intelligence.
Moon, Hyeong Cheol; Park, Chan-A; Jeon, Yeong-Jae; You, Soon Tae; Baek, Hyun Man; Lee, Youn Joo; Cho, Chul Beom; Cheong, Chae Joon; Park, Young Seok
2018-05-16
The cingulate cortex (CC) is a brain region that plays a key role in pain processing, but CC abnormalities are not unclear in patients with trigeminal neuralgia (TN). The purpose of this study was to determine the central causal mechanisms of TN and the surrounding brain structure in healthy controls and patients with TN using 7 Tesla (T) magnetic resonance imaging (MRI). Whole-brain parcellation in gray matter volume and thickness was assessed in 15 patients with TN and 16 healthy controls matched for sex, age, and regional variability using T1-weighted imaging. Regions of interest (ROIs) were measured in rostral anterior CC (rACC), caudal anterior CC (cACC) and posterior CC (PCC). We also investigated associations between gray matter volume or thickness and clinical symptoms, such as pain duration, Barrow Neurologic Institute (BNI) scores, offender vessel, and medications, in patients with TN. The cACC and PCC exhibited gray matter atrophy and reduced thickness between the TN and control groups. However, the rACC did not. Cortical volumes were negatively correlated with pain duration in transverse and inferior temporal areas, and thickness was also negatively correlated with pain duration in superior frontal and parietal areas. The cACC and PCC gray matter atrophy occurred in the patients with TN, and pain duration was associated with frontal, parietal, and temporal cortical regions. These results suggest that the cACC, PCC but not the rACC are associated with central pain mechanisms in TN. Copyright © 2018 Elsevier Inc. All rights reserved.
Chen, Yu-Chen; Liu, Shenghua; Lv, Han; Bo, Fan; Feng, Yuan; Chen, Huiyou; Xu, Jin-Jing; Yin, Xindao; Wang, Shukui; Gu, Jian-Ping
2018-01-01
Purpose: The anterior cingulate cortex (ACC) has been suggested to be involved in chronic subjective tinnitus. Tinnitus may arise from aberrant functional coupling between the ACC and cerebral cortex. To explore this hypothesis, we used resting-state functional magnetic resonance imaging (fMRI) to illuminate the functional connectivity (FC) network of the ACC subregions in chronic tinnitus patients. Methods: Resting-state fMRI scans were obtained from 31 chronic right-sided tinnitus patients and 40 healthy controls (age, sex, and education well-matched) in this study. Rostral ACC and dorsal ACC were selected as seed regions to investigate the intrinsic FC with the whole brain. The resulting FC patterns were correlated with clinical tinnitus characteristics including the tinnitus duration and tinnitus distress. Results: Compared with healthy controls, chronic tinnitus patients showed disrupted FC patterns of ACC within several brain networks, including the auditory cortex, prefrontal cortex, visual cortex, and default mode network (DMN). The Tinnitus Handicap Questionnaires (THQ) scores showed positive correlations with increased FC between the rostral ACC and left precuneus (r = 0.507, p = 0.008) as well as the dorsal ACC and right inferior parietal lobe (r = 0.447, p = 0.022). Conclusions: Chronic tinnitus patients have abnormal FC networks originating from ACC to other selected brain regions that are associated with specific tinnitus characteristics. Resting-state ACC-cortical FC disturbances may play an important role in neuropathological features underlying chronic tinnitus. PMID:29410609
Prefrontal inhibition of threat processing reduces working memory interference
Clarke, Robert; Johnstone, Tom
2013-01-01
Bottom-up processes can interrupt ongoing cognitive processing in order to adaptively respond to emotional stimuli of high potential significance, such as those that threaten wellbeing. However it is vital that this interference can be modulated in certain contexts to focus on current tasks. Deficits in the ability to maintain the appropriate balance between cognitive and emotional demands can severely impact on day-to-day activities. This fMRI study examined this interaction between threat processing and cognition; 18 adult participants performed a visuospatial working memory (WM) task with two load conditions, in the presence and absence of anxiety induction by threat of electric shock. Threat of shock interfered with performance in the low cognitive load condition; however interference was eradicated under high load, consistent with engagement of emotion regulation mechanisms. Under low load the amygdala showed significant activation to threat of shock that was modulated by high cognitive load. A directed top-down control contrast identified two regions associated with top-down control; ventrolateral PFC and dorsal ACC. Dynamic causal modeling provided further evidence that under high cognitive load, top-down inhibition is exerted on the amygdala and its outputs to prefrontal regions. Additionally, we hypothesized that individual differences in a separate, non-emotional top-down control task would predict the recruitment of dorsal ACC and ventrolateral PFC during top-down control of threat. Consistent with this, performance on a separate dichotic listening task predicted dorsal ACC and ventrolateral PFC activation during high WM load under threat of shock, though activation in these regions did not directly correlate with WM performance. Together, the findings suggest that under high cognitive load and threat, top-down control is exerted by dACC and vlPFC to inhibit threat processing, thus enabling WM performance without threat-related interference. PMID:23750133
Adenoid cystic carcinoma: emerging role of translocations and gene fusions
Wysocki, Piotr T.; Izumchenko, Evgeny; Meir, Juliet; Ha, Patrick K.; Sidransky, David; Brait, Mariana
2016-01-01
Adenoid cystic carcinoma (ACC), the second most common salivary gland malignancy, is notorious for poor prognosis, which reflects the propensity of ACC to progress to clinically advanced metastatic disease. Due to high long-term mortality and lack of effective systemic treatment, the slow-growing but aggressive ACC poses a particular challenge in head and neck oncology. Despite the advancements in cancer genomics, up until recently relatively few genetic alterations critical to the ACC development have been recognized. Although the specific chromosomal translocations resulting in MYB-NFIB fusions provide insight into the ACC pathogenesis and represent attractive diagnostic and therapeutic targets, their clinical significance is unclear, and a substantial subset of ACCs do not harbor the MYB-NFIB translocation. Strategies based on detection of newly described genetic events (such as MYB activating super-enhancer translocations and alterations affecting another member of MYB transcription factor family-MYBL1) offer new hope for improved risk assessment, therapeutic intervention and tumor surveillance. However, the impact of these approaches is still limited by an incomplete understanding of the ACC biology, and the manner by which these alterations initiate and drive ACC remains to be delineated. This manuscript summarizes the current status of gene fusions and other driver genetic alterations in ACC pathogenesis and discusses new therapeutic strategies stemming from the current research. PMID:27533466
Velasquez, Francisco; Wiggins, Jillian Lee; Mattson, Whitney I; Martin, Donna M; Lord, Catherine; Monk, Christopher S
2017-04-01
Social deficits in autism spectrum disorder (ASD) are linked to amygdala functioning and functional connection between the amygdala and subgenual anterior cingulate cortex (sACC) is involved in the modulation of amygdala activity. Impairments in behavioral symptoms and amygdala activation and connectivity with the sACC seem to vary by serotonin transporter-linked polymorphic region (5-HTTLPR) variant genotype in diverse populations. The current preliminary investigation examines whether amygdala-sACC connectivity differs by 5-HTTLPR genotype and relates to social functioning in ASD. A sample of 108 children and adolescents (44 ASD) completed an fMRI face-processing task. Youth with ASD and low expressing 5-HTTLPR genotypes showed significantly greater connectivity than youth with ASD and higher expressing genotypes as well as typically developing (TD) individuals with both low and higher expressing genotypes, in the comparison of happy vs. baseline faces and happy vs. neutral faces. Moreover, individuals with ASD and higher expressing genotypes exhibit a negative relationship between amygdala-sACC connectivity and social dysfunction. Altered amygdala-sACC coupling based on 5-HTTLPR genotype may help explain some of the heterogeneity in neural and social function observed in ASD. This is the first ASD study to combine genetic polymorphism analyses and functional connectivity in the context of a social task. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
The atmospheric ocean: eddies and jets in the Antarctic Circumpolar Current.
Thompson, Andrew F
2008-12-28
Although the Antarctic Circumpolar Current (ACC) is the longest and the strongest oceanic current on the Earth and is the primary means of inter-basin exchange, it remains one of the most poorly represented components of global climate models. Accurately describing the circulation of the ACC is made difficult owing to the prominent role that mesoscale eddies and jets, oceanic equivalents of atmospheric storms and storm tracks, have in setting the density structure and transport properties of the current. The successes and limitations of different representations of eddy processes in models of the ACC are considered, with particular attention given to how the circulation responds to changes in wind forcing. The dynamics of energetic eddies and topographically steered jets may both temper and enhance the sensitivity of different aspects of the ACC's circulation to changes in climate.
From mesoscale eddies to small-scale turbulence in the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Naveira Garabato, A.; Brearley, J. A.; Sheen, K. L.; Waterman, S. N.
2012-12-01
A foremost question in physical oceanography is that of how the oceanic mesoscale dissipates. The Antarctic Circumpolar Current (ACC), in the Southern Ocean, is forced strongly by the wind and hosts a vigorous mesoscale eddy field. It has been recently suggested that substantial dampening of mesoscale flows in the region may occur through interactions with topography, on the basis of a number of indirect approaches. Here, we present the first direct evidence of a transfer of energy between mesoscale eddies and small-scale turbulence in the ACC, via the radiation, instability and breaking of internal waves generated as mesoscale flows impinge on rough topography. The evidence is provided by analysis of two data sets gathered by the DIMES (Diapycnal and Isopycnal Experiment in the Southern Ocean) experiment: (1) the observations of a mooring cluster, specifically designed to measure dynamical exchanges between the mesoscale eddy and internal wave fields in Drake Passage over a 2-year deployment; and (2) an extensive fine- and microstructure survey of the region. The physical mechanisms implicated in the cascade of energy across scales will be discussed.
Szekely, Akos; Silton, Rebecca L.; Heller, Wendy; Miller, Gregory A.
2017-01-01
Abstract The rostral-ventral subdivision of the anterior cingulate cortex (rACC) plays a key role in the regulation of emotional processing. Although rACC has strong anatomical connections with anterior insular cortex (AIC), amygdala, prefrontal cortex and striatal brain regions, it is unclear whether the functional connectivity of rACC with these regions changes when regulating emotional processing. Furthermore, it is not known whether this connectivity changes with deficits in emotion regulation seen in different kinds of anxiety and depression. To address these questions regarding rACC functional connectivity, non-patients high in self-reported anxious apprehension (AP), anxious arousal (AR), anhedonic depression (AD) or none (CON) indicated the ink color of pleasant, neutral and unpleasant words during functional magnetic resonance imaging. While ignoring task-irrelevant unpleasant words, AD and CON showed an increase in the functional connectivity of rACC with AIC, putamen, caudate and ventral pallidum. There was a decrease in this connectivity in AP and AR, with AP showing greater reduction than AR. These findings provide support for the role of rACC in integrating interoceptive, emotional and cognitive functions via interactions with insula and striatal regions during effective emotion regulation in healthy individuals and a failure of this integration that may be specific to anxiety, particularly AP. PMID:27998997
Tracking the Polar Front south of New Zealand using penguin dive data
NASA Astrophysics Data System (ADS)
Sokolov, Serguei; Rintoul, Stephen R.; Wienecke, Barbara
2006-04-01
Nearly 36,000 vertical temperature profiles collected by 15 king penguins are used to map oceanographic fronts south of New Zealand. There is good correspondence between Antarctic Circumpolar Current (ACC) front locations derived from temperatures sampled in the upper 150 m along the penguin tracks and front positions inferred using maps of sea surface height (SSH). Mesoscale features detected in the SSH maps from this eddy-rich region are also reproduced in the individual temperature sections based on dive data. The foraging strategy of Macquarie Island king penguins appears to be influenced strongly by oceanographic structure: almost all the penguin dives are confined to the region close to and between the northern and southern branches of the Polar Front. Surface chlorophyll distributions also reflect the influence of the ACC fronts, with the northern branch of the Polar Front marking a boundary between low surface chlorophyll to the north and elevated values to the south.
Wu, Minjie; Kujawa, Autumn; Lu, Lisa H.; Fitzgerald, Daniel A.; Klumpp, Heide; Fitzgerald, Kate D.; Monk, Christopher S.; Phan, K. Luan
2016-01-01
The ability to process and respond to emotional facial expressions is a critical skill for healthy social and emotional development. There has been growing interest in understanding the neural circuitry underlying development of emotional processing, with previous research implicating functional connectivity between amygdala and frontal regions. However, existing work has focused on threatening emotional faces, raising questions regarding the extent to which these developmental patterns are specific to threat or to emotional face processing more broadly. In the current study, we examined age-related changes in brain activity and amygdala functional connectivity during an fMRI emotional face matching task (including angry, fearful and happy faces) in 61 healthy subjects aged 7–25 years. We found age-related decreases in ventral medial prefrontal cortex (vmPFC) activity in response to happy faces but not to angry or fearful faces, and an age-related change (shifting from positive to negative correlation) in amygdala-anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC) functional connectivity to all emotional faces. Specifically, positive correlations between amygdala and ACC/mPFC in children changed to negative correlations in adults, which may suggest early emergence of bottom-up amygdala excitatory signaling to ACC/mPFC in children and later development of top-down inhibitory control of ACC/mPFC over amygdala in adults. Age-related changes in amygdala-ACC/mPFC connectivity did not vary for processing of different facial emotions, suggesting changes in amygdala-ACC/mPFC connectivity may underlie development of broad emotional processing, rather than threat-specific processing. PMID:26931629
Li, Meng; Demenescu, Liliana Ramona; Colic, Lejla; Metzger, Coraline Danielle; Heinze, Hans-Jochen; Steiner, Johann; Speck, Oliver; Fejtova, Anna; Salvadore, Giacomo; Walter, Martin
2017-05-01
The anterior cingulate cortex (ACC) has shown decreased glutamate levels in patients with major depressive disorder. Subanesthetic doses of ketamine were repeatedly shown to improve depressive symptoms within 24 h after infusion and this antidepressant effect was attributed to increased α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) throughput. To elucidate ketamine's mechanism of action, we tested whether the clinical time course of the improvement is mirrored by the change of glutamine/glutamate ratio and if such effects show a regional and temporal specificity in two distinct subdivisions of ACC with different AMPA/N-methyl-D-aspartate receptor profiles. In a double-blind, placebo-controlled intravenous infusion study of ketamine, we measured glutamate and glutamine in the pregenual ACC (pgACC) and the anterior midcingulate cortex at 1 and 24 h post infusion with magnetic resonance spectroscopy at 7 T. A significant interaction of time, region, and treatment was found for the glutamine/glutamate ratios (placebo, n=14; ketamine, n=12). Post-hoc analyses revealed that the glutamine/glutamate ratio increased significantly in the ketamine group, compared with placebo, specifically in the pgACC after 24 h. The glutamine/glutamate increase in the pgACC caused by ketamine at 24 h post infusion was reproduced in an enlarged sample (placebo, n=24; ketamine, n=20). Our results support a significant temporal and regional response in glutamine/glutamate ratios to a single subanesthetic dose of ketamine, which mirrors the time course of the antidepressant response and reversal of the molecular deficits in patients and which may be associated with the histoarchitectonical receptor fingerprints of the ACC subregions.
Li, Meng; Demenescu, Liliana Ramona; Colic, Lejla; Metzger, Coraline Danielle; Heinze, Hans-Jochen; Steiner, Johann; Speck, Oliver; Fejtova, Anna; Salvadore, Giacomo; Walter, Martin
2017-01-01
The anterior cingulate cortex (ACC) has shown decreased glutamate levels in patients with major depressive disorder. Subanesthetic doses of ketamine were repeatedly shown to improve depressive symptoms within 24 h after infusion and this antidepressant effect was attributed to increased α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) throughput. To elucidate ketamine's mechanism of action, we tested whether the clinical time course of the improvement is mirrored by the change of glutamine/glutamate ratio and if such effects show a regional and temporal specificity in two distinct subdivisions of ACC with different AMPA/N-methyl-D-aspartate receptor profiles. In a double-blind, placebo-controlled intravenous infusion study of ketamine, we measured glutamate and glutamine in the pregenual ACC (pgACC) and the anterior midcingulate cortex at 1 and 24 h post infusion with magnetic resonance spectroscopy at 7 T. A significant interaction of time, region, and treatment was found for the glutamine/glutamate ratios (placebo, n=14; ketamine, n=12). Post-hoc analyses revealed that the glutamine/glutamate ratio increased significantly in the ketamine group, compared with placebo, specifically in the pgACC after 24 h. The glutamine/glutamate increase in the pgACC caused by ketamine at 24 h post infusion was reproduced in an enlarged sample (placebo, n=24; ketamine, n=20). Our results support a significant temporal and regional response in glutamine/glutamate ratios to a single subanesthetic dose of ketamine, which mirrors the time course of the antidepressant response and reversal of the molecular deficits in patients and which may be associated with the histoarchitectonical receptor fingerprints of the ACC subregions. PMID:27604568
Ecological importance of the Southern Boundary of the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Tynan, Cynthia T.
1998-04-01
The Southern Ocean surrounds the Antarctic continent and supports one of the most productive marine ecosystems. Migratory and endemic species of whales, seals and birds benefit from the high biomass of their principal prey, krill (Euphausia superba) and cephalopods, in this area. Most species of baleen whales and male sperm whales in the Southern Hemisphere migrate between low-latitude breeding grounds in winter and highly productive Antarctic feeding grounds in summer. Here I show the importance of the southernmost reaches of the strongest ocean current, the Antarctic Circumpolar Current (ACC), to a complex and predictable food web of the Southern Ocean. The circumpolar distributions of blue, fin and humpback whales from spring to midsummer trace the non-uniform high-latitude penetration of shoaled, nutrient-rich Upper Circumpolar Deep Water, which is carried eastward by the ACC. The poleward extent of this water mass delineates the Southern Boundary of the ACC and corresponds not only to the circumpolar distributions of baleen whales, but also to distributions of krill and to regions of high, seasonally averaged, phytoplankton biomass. Sperm whales, which feed on cephalopods, also congregate in highest densities near the Southern Boundary. The association of primary production, Krill, and whales with the Southern Boundary, suggests that it provides predictably productive foraging for many species, and is of critical importance to the function of the Southern Ocean ecosystem.
Southern Ocean Eddy Heat Flux and Eddy-Mean Flow Interactions in Drake Passage
NASA Astrophysics Data System (ADS)
Foppert, Annie
The Antarctic Circumpolar Current (ACC) is a complex current system composed of multiple jets that is both unique to the world's oceans and relatively under observed compared with other current systems. Observations taken by current- and pressure-recording inverted echo sounders (CPIES) over four years, from November 2007 to November 2011, quantify the mean structure of one of the main jets of the ACC - the Polar Front - in a composite-mean sense. While the array of CPIES deployed in Drake Passage included a 3 x 7 local dynamics array, analysis of the Polar Front makes use of the line of CPIES that spanned the width of Drake Passage (C-Line). The Polar Front tends to prefer one of two locations, separated along the C-Line by 1° of latitude, with the core of the jet centered on corresponding geopotential height contours (with a 17 cm dierence between the northern and southern jets). Potential vorticity fields suggest that the Polar Front is susceptible to baroclinic instability, regardless of whether it is found upstream (farther south along the C-Line) or downstream (farther north along the C-Line) of the Shackleton Fracture Zone (SFZ), yet the core of the jet remains a barrier to smaller-scale mixing, as inferred from estimated mixing lengths. Within the local dynamics array of CPIES, the observed offset between eddy heat flux (EHF) and eddy kinetic energy (EKE) and the alignment of EHF with sea surface height (SSH) standard deviation motivates a proxy for depth-integrated EHF that can be estimated from available satellite SSH data. An eddy-resolving numerical model develops the statistics of a logarithmic fit between SSH standard deviation and cross-frontal EHF that is applied to the ACC in a circumglobal sense. We find 1.06 PW enters the ACC from the north and 0.02 PW exits towards Antarctica. The magnitude of the estimated EHF, along with contemporaneous estimates of the mean heat flux, suggests that the air-sea heat flux south of the PF is an overestimate. Long-term trends in EHF are calculated from January 1992 to December 2014 and reveal varying trends at the eight ACC EHF hot spots, with only three having statistically significant temporal trends of strengthening cross-frontal EHF. The dynamics of an oceanic storm track are investigated using CPIES observations in the local dynamics array to better understand the processes responsible for the spatial oset between EHF and EKE. Wave activity flux ( W), calculated from the total geostrophic stream-function, is used to diagnose eddy-mean flow interactions in the eddy-rich region immediately downstream of the SFZ. In the full four-year mean and in a composite of eddy events, elevated values of eddy potential energy (EPE) are aligned with the vertical component of W. This is indicative of a conversion of mean available potential energy to EPE through EHF associated with baroclinic instability. Emanating from this region, horizontal W vectors point towards the adjacent region of elevated EKE. A case study of an eddy event, lasting from 15 to 23 July 2010, is presented and highlights the capability of W to illustrate the evolution of the storm track in a snap-shot sense. While baroclinic processes initially dominate the event, the alignment of elevated values of EKE with the convergence of the horizontal W vectors indicates the importance of barotropic processes in transporting EKE away from the ACC's interaction with the SFZ.
Becker, Michael P I; Nitsch, Alexander M; Hewig, Johannes; Miltner, Wolfgang H R; Straube, Thomas
2016-12-01
Several regions of the frontal cortex interact with striatal and amygdala regions to mediate the evaluation of reward-related information and subsequent adjustment of response choices. Recent theories discuss the particular relevance of dorsal anterior cingulate cortex (dACC) for switching behavior; consecutively, ventromedial prefrontal cortex (VMPFC) is involved in mediating exploitative behaviors by tracking reward values unfolding after the behavioral switch. Amygdala, on the other hand, has been implied in coding the valence of stimulus-outcome associations and the ventral striatum (VS) has consistently been shown to code a reward prediction error (RPE). Here, we used fMRI data acquired in humans during a reversal task to parametrically model different sequences of positive feedback in order to unravel differential contributions of these brain regions to the tracking and exploitation of rewards. Parameters from an Optimal Bayesian Learner accurately predicted the divergent involvement of dACC and VMPFC during feedback processing: dACC signaled the first, but not later, presentations of positive feedback, while VMPFC coded trial-by-trial accumulations in reward value. Our results confirm that dACC carries a prominent confirmatory signal during processing of first positive feedback. Amygdala coded positive feedbacks more uniformly, while striatal regions were associated with RPE. Copyright © 2016 Elsevier Inc. All rights reserved.
Vanderstraeten, Lisa; Van Der Straeten, Dominique
2017-01-01
1-aminocyclopropane-1-carboxylic acid (ACC) is a non-protein amino acid acting as the direct precursor of ethylene, a plant hormone regulating a wide variety of vegetative and developmental processes. ACC is the central molecule of ethylene biosynthesis. The rate of ACC formation differs in response to developmental, hormonal and environmental cues. ACC can be conjugated to three derivatives, metabolized in planta or by rhizobacteria using ACC deaminase, and is transported throughout the plant over short and long distances, remotely leading to ethylene responses. This review highlights some recent advances related to ACC. These include the regulation of ACC synthesis, conjugation and deamination, evidence for a role of ACC as an ethylene-independent signal, short and long range ACC transport, and the identification of a first ACC transporter. Although unraveling the complex mechanism of ACC transport is in its infancy, new questions emerge together with the identification of a first transporter. In the light of the future quest for additional ACC transporters, this review presents perspectives of the novel findings and includes considerations for future research toward applications in agronomy. PMID:28174583
Vanderstraeten, Lisa; Van Der Straeten, Dominique
2017-01-01
1-aminocyclopropane-1-carboxylic acid (ACC) is a non-protein amino acid acting as the direct precursor of ethylene, a plant hormone regulating a wide variety of vegetative and developmental processes. ACC is the central molecule of ethylene biosynthesis. The rate of ACC formation differs in response to developmental, hormonal and environmental cues. ACC can be conjugated to three derivatives, metabolized in planta or by rhizobacteria using ACC deaminase, and is transported throughout the plant over short and long distances, remotely leading to ethylene responses. This review highlights some recent advances related to ACC. These include the regulation of ACC synthesis, conjugation and deamination, evidence for a role of ACC as an ethylene-independent signal, short and long range ACC transport, and the identification of a first ACC transporter. Although unraveling the complex mechanism of ACC transport is in its infancy, new questions emerge together with the identification of a first transporter. In the light of the future quest for additional ACC transporters, this review presents perspectives of the novel findings and includes considerations for future research toward applications in agronomy.
Denke, Claudia; Rotte, Michael; Heinze, Hans-Jochen; Schaefer, Michael
2014-01-01
Previous studies identified a network of brain regions involved in the perception of norm violations, including insula, anterior cingulate cortex (ACC), and right temporoparietal junction area (RTPJ). Activations in these regions are suggested to reflect the perception of norm violations and unfairness. The current study aimed to test this hypothesis by exploring whether a personal disposition to perceive the world as being just is related to neural responses to moral evaluations. The just-world-hypothesis describes a cognitive bias to believe in a just world in which everyone gets what he or she deserves and deserves what he or she gets. Since it has been demonstrated that ACC, RTPJ, and insula are involved in the perception of unfairness, we hypothesized that individual differences in the belief in a just world are reflected by different activations of these brain areas. Participants were confronted with scenarios describing norm-violating or -confirming behavior. FMRI results revealed an activation of dorsal ACC, RTPJ, and insula when perceiving norm violations, but only activity in insula/somatosensory cortex correlated with the belief in a just world. Thus, our results suggest a role for insula/somatosensory cortex for the belief in a just world.
Fan, Siyan; Cath, Danielle C; van den Heuvel, Odile A; van der Werf, Ysbrand D; Schöls, Caroline; Veltman, Dick J; Pouwels, Petra J W
2017-03-01
Abnormal glutamatergic transmission in cortico-striato-thalamo-cortical (CSTC) circuits is thought to be involved in the pathophysiology of Tourette's disorder (TD) and obsessive-compulsive disorder (OCD). Using proton magnetic resonance spectroscopy, the current study aimed to investigate regional concentrations of glutamatergic compounds in TD and OCD patients in comparison to healthy control subjects (HC). Twenty-three TD patients, 20 OCD patients and 22 HC were included. Short echo-time single-voxel 3T MRS was obtained from dorsal anterior cingulate cortex (dACC) and midline bilateral thalamus. The 3-group comparison showed a significant difference in choline concentration in the thalamus. Thalamic choline was highest in OCD patients, showing a significant difference with TD, and a trend compared to HC (post-hoc analyses). Glutamine in dACC correlated negatively with tic severity scores in TD patients, while glutamate in thalamus correlated positively with anxiety severity scores in OCD patients. These findings suggest subtle differences in metabolites in CSTC areas between TD and OCD. Alterations of choline concentrations seem to be both regional (only in thalamus, not in dACC) and disease specific in OCD pathology. The findings need replication in larger groups, but encourage further research into glutamatergic metabolites in TD and OCD. Copyright © 2017 Elsevier Ltd. All rights reserved.
Self-referential processing influences functional activation during cognitive control: an fMRI study
Koch, Kathrin; Schachtzabel, Claudia; Peikert, Gregor; Schultz, Carl Christoph; Reichenbach, Jürgen R.; Sauer, Heinrich; Schlösser, Ralf G.
2013-01-01
Rostral anterior cingulate cortex (rACC) plays a central role in the pathophysiology of major depressive disorder (MDD). As we reported in our previous study (Wagner et al., 2006), patients with MDD were characterized by an inability to deactivate this region during cognitive processing leading to a compensatory prefrontal hyperactivation. This hyperactivation in rACC may be related to a deficient inhibitory control of negative self-referential processes, which in turn may interfere with cognitive control task execution and the underlying fronto-cingulate network activation. To test this assumption, a functional magnetic resonance imaging study was conducted in 34 healthy subjects. Univariate and functional connectivity analyses in statistical parametric mapping software 8 were used. Self-referential stimuli and the Stroop task were presented in an event-related design. As hypothesized, rACC was specifically engaged during negative self-referential processing (SRP) and was significantly related to the degree of depressive symptoms in participants. BOLD signal in rACC showed increased valence-dependent (negative vs neutral SRP) interaction with BOLD signal in prefrontal and dorsal anterior cingulate regions during Stroop task performance. This result provides strong support for the notion that enhanced rACC interacts with brain regions involved in cognitive control processes and substantiates our previous interpretation of increased rACC and prefrontal activation in patients during Stroop task. PMID:22798398
Szekely, Akos; Silton, Rebecca L; Heller, Wendy; Miller, Gregory A; Mohanty, Aprajita
2017-03-01
The rostral-ventral subdivision of the anterior cingulate cortex (rACC) plays a key role in the regulation of emotional processing. Although rACC has strong anatomical connections with anterior insular cortex (AIC), amygdala, prefrontal cortex and striatal brain regions, it is unclear whether the functional connectivity of rACC with these regions changes when regulating emotional processing. Furthermore, it is not known whether this connectivity changes with deficits in emotion regulation seen in different kinds of anxiety and depression. To address these questions regarding rACC functional connectivity, non-patients high in self-reported anxious apprehension (AP), anxious arousal (AR), anhedonic depression (AD) or none (CON) indicated the ink color of pleasant, neutral and unpleasant words during functional magnetic resonance imaging. While ignoring task-irrelevant unpleasant words, AD and CON showed an increase in the functional connectivity of rACC with AIC, putamen, caudate and ventral pallidum. There was a decrease in this connectivity in AP and AR, with AP showing greater reduction than AR. These findings provide support for the role of rACC in integrating interoceptive, emotional and cognitive functions via interactions with insula and striatal regions during effective emotion regulation in healthy individuals and a failure of this integration that may be specific to anxiety, particularly AP. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Toyoshima, K; Kimura, S; Cheng, J; Oda, Y; Mori, K J; Saku, T
1999-03-01
To understand the morphogenesis of characteristic cribriform structures and the frequent invasion of salivary adenoid cystic carcinomas (ACC) along such basement membrane-rich structures as peripheral nerves, we have isolated fibronectin (FN) from the culture media of ACC3 cells established from a parotid ACC and characterized its glycosylation and alternative splicing status. FN isolated from ACC3 cells (ACC-FN) showed a molecular mass of 315 kDa in SDS-PAGE and was less heterogeneous and larger than plasma FN (pFN) or FNs from other cell sources. Differential enzymatic treatments of immunoprecipitated ACC-FN with neuraminidase, peptide-N-glycosidase F and endo-alpha-N-acetylgalactosaminidase revealed that ACC-FN was composed of a polypeptide chain of 270 kDa, with 10 kDa each of N-linked and O-linked oligosaccharide chains. Reverse transcription polymerase chain reaction (RT-PCR), in-situ hybridization, and immunofluorescence studies showed that most ACC-FNs contained ED-A, ED-B and IIICS regions in the molecules. This alternative splicing status of ACC-FN seemed to contribute to its less heterogeneous and larger molecular form. Cell attachment assay demonstrated that ACC-FN was more potent than pFN in adhesion of ACC3 cells. The results indicated that ACC-FN may function as a substrate for attachment of ACC3 cells, or that ACC3 cells trap and retain ACC-FN in their pericellular space. This isoform of FN may play an important role in the mode of invasion of ACC and the formation of stromal pseudocysts in the characteristic cribriform structure of ACC.
Hakamata, Yuko; Iwase, Mikio; Kato, Takashi; Senda, Kohei; Inada, Toshiya
2013-01-01
Background Human personality consists of two fundamental elements character and temperament. Character allays automatic and preconceptual emotional responses determined by temperament. However, the neurobiological basis of character and its interplay with temperament remain elusive. Here, we examined character-temperament interplay and explored the neural basis of character, with a particular focus on the subgenual anterior cingulate cortex extending to a ventromedial portion of the prefrontal cortex (sgACC/vmPFC). Methods Resting brain glucose metabolism (GM) was measured using [18F] fluorodeoxyglucose positron emission tomography in 140 healthy adults. Personality traits were assessed using the Temperament and Character Inventory. Regions of interest (ROI) analysis and whole-brain analysis were performed to examine a combination effect of temperament and character on the sgACC/vmPFC and to explore the neural correlates of character, respectively. Results Harm avoidance (HA), a temperament trait (i.e., depressive, anxious, vulnerable), showed a significant negative impact on the sgACC/vmPFC GM, whereas self-transcendence (ST), a character trait (i.e., intuitive, judicious, spiritual), exhibited a significant positive effect on GM in the same region (HA β = −0.248, p = 0.003; ST: β = 0.250, p = 0.003). In addition, when coupled with strong ST, individuals with strong HA maintained the sgACC/vmPFC GM level comparable to the level of those with low scores on both HA and ST. Furthermore, exploratory whole-brain analysis revealed a significant positive relationship between ST and sgACC/vmPFC GM (peak voxel at x = −8, y = 32, z = −8, k = 423, Z = 4.41, corrected p FDR = 0.030). Conclusion The current findings indicate that the sgACC/vmPFC might play a critical role in mindful awareness to something beyond as well as in emotional regulation. Developing a sense of mindfulness may temper exaggerated emotional responses in individuals with a risk for or having anxiety and depressive disorders. PMID:24130715
Hakamata, Yuko; Iwase, Mikio; Kato, Takashi; Senda, Kohei; Inada, Toshiya
2013-01-01
Human personality consists of two fundamental elements character and temperament. Character allays automatic and preconceptual emotional responses determined by temperament. However, the neurobiological basis of character and its interplay with temperament remain elusive. Here, we examined character-temperament interplay and explored the neural basis of character, with a particular focus on the subgenual anterior cingulate cortex extending to a ventromedial portion of the prefrontal cortex (sgACC/vmPFC). Resting brain glucose metabolism (GM) was measured using [(18)F] fluorodeoxyglucose positron emission tomography in 140 healthy adults. Personality traits were assessed using the Temperament and Character Inventory. Regions of interest (ROI) analysis and whole-brain analysis were performed to examine a combination effect of temperament and character on the sgACC/vmPFC and to explore the neural correlates of character, respectively. Harm avoidance (HA), a temperament trait (i.e., depressive, anxious, vulnerable), showed a significant negative impact on the sgACC/vmPFC GM, whereas self-transcendence (ST), a character trait (i.e., intuitive, judicious, spiritual), exhibited a significant positive effect on GM in the same region (HA β = -0.248, p = 0.003; ST: β = 0.250, p = 0.003). In addition, when coupled with strong ST, individuals with strong HA maintained the sgACC/vmPFC GM level comparable to the level of those with low scores on both HA and ST. Furthermore, exploratory whole-brain analysis revealed a significant positive relationship between ST and sgACC/vmPFC GM (peak voxel at x = -8, y = 32, z = -8, k = 423, Z = 4.41, corrected p (FDR) = 0.030). The current findings indicate that the sgACC/vmPFC might play a critical role in mindful awareness to something beyond as well as in emotional regulation. Developing a sense of mindfulness may temper exaggerated emotional responses in individuals with a risk for or having anxiety and depressive disorders.
Holmes, Avram J; Bogdan, Ryan; Pizzagalli, Diego A
2010-04-01
A variable number of tandem repeats (short (S) vs long (L)) in the promoter region of the serotonin transporter gene (5-HTTLPR) and a functional variant of a single-nucleotide polymorphism (rs25531) in 5-HTTLPR have been recently associated with increased risk for major depressive disorder (MDD). In particular, relative to L/L or L(A) homozygotes (hereafter referred to as L' participants), S carriers or L(g)-allele carriers (S' participants) have been found to have a higher probability of developing depression after stressful life events, although inconsistencies abound. Previous research indicates that patients with MDD are characterized by executive dysfunction and abnormal activation within the anterior cingulate cortex (ACC), particularly in situations requiring adaptive behavioral adjustments following errors and response conflict (action monitoring). The goal of this study was to test whether psychiatrically healthy S' participants would show abnormalities similar to those of MDD subjects. To this end, 19 S' and 14 L' participants performed a modified Flanker task known to induce errors, response conflict, and activations in various ACC subdivisions during functional magnetic resonance imaging. As hypothesized, relative to L' participants, S' participants showed (1) impaired post-error and post-conflict behavioral adjustments; (2) larger error-related rostral ACC activation; and (3) lower conflict-related dorsal ACC activation. As similar behavioral and neural dysfunctions have been recently described in MDD patient samples, the current results raise the possibility that impaired action monitoring and associated ACC dysregulation may represent risk factors increased vulnerability to depression.
Metastatic adrenal cortical carcinoma to T12 vertebrae.
Lee, Daniel; Yanamadala, Vijay; Shankar, Ganesh M; Shin, John H
2016-05-01
We report spinal metastasis of adrenal cortical carcinoma (ACC) to the T12 vertebrae with epidural extension. ACC is a rare malignancy with poor prognosis and high rates of metastasis. However, spinal lesions of ACC are rare, and few have been reported in the literature. We discuss our management of this lesion and review the current understanding and treatment of ACC and spinal metastasis. Copyright © 2015 Elsevier Ltd. All rights reserved.
Wu, Minjie; Kujawa, Autumn; Lu, Lisa H; Fitzgerald, Daniel A; Klumpp, Heide; Fitzgerald, Kate D; Monk, Christopher S; Phan, K Luan
2016-05-01
The ability to process and respond to emotional facial expressions is a critical skill for healthy social and emotional development. There has been growing interest in understanding the neural circuitry underlying development of emotional processing, with previous research implicating functional connectivity between amygdala and frontal regions. However, existing work has focused on threatening emotional faces, raising questions regarding the extent to which these developmental patterns are specific to threat or to emotional face processing more broadly. In the current study, we examined age-related changes in brain activity and amygdala functional connectivity during an fMRI emotional face matching task (including angry, fearful, and happy faces) in 61 healthy subjects aged 7-25 years. We found age-related decreases in ventral medial prefrontal cortex activity in response to happy faces but not to angry or fearful faces, and an age-related change (shifting from positive to negative correlation) in amygdala-anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC) functional connectivity to all emotional faces. Specifically, positive correlations between amygdala and ACC/mPFC in children changed to negative correlations in adults, which may suggest early emergence of bottom-up amygdala excitatory signaling to ACC/mPFC in children and later development of top-down inhibitory control of ACC/mPFC over amygdala in adults. Age-related changes in amygdala-ACC/mPFC connectivity did not vary for processing of different facial emotions, suggesting changes in amygdala-ACC/mPFC connectivity may underlie development of broad emotional processing, rather than threat-specific processing. Hum Brain Mapp 37:1684-1695, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Fronto-Striatal Glutamate in Autism Spectrum Disorder and Obsessive Compulsive Disorder.
Naaijen, Jilly; Zwiers, Marcel P; Amiri, Houshang; Williams, Steven C R; Durston, Sarah; Oranje, Bob; Brandeis, Daniel; Boecker-Schlier, Regina; Ruf, Matthias; Wolf, Isabella; Banaschewski, Tobias; Glennon, Jeffrey C; Franke, Barbara; Buitelaar, Jan K; Lythgoe, David J
2017-11-01
Autism spectrum disorders (ASDs) and obsessive compulsive disorder (OCD) are often comorbid with the overlap based on compulsive behaviors. Although previous studies suggest glutamatergic deficits in fronto-striatal brain areas in both disorders, this is the first study to directly compare the glutamate concentrations across the two disorders with those in healthy control participants using both categorical and dimensional approaches. In the current multi-center study (four centers), we used proton magnetic resonance spectroscopy in 51 children with ASD, 29 with OCD, and 53 healthy controls (aged 8-13 years) to investigate glutamate (Glu) concentrations in two regions of the fronto-striatal circuit: midline anterior cingulate cortex (ACC) and left dorsal striatum. Spectra were processed with Linear Combination Model. Group comparisons were performed with one-way analyses of variance including sex, medication use, and scanner site as covariates. In addition, a dimensional analysis was performed, linking glutamate with a continuous measure of compulsivity across disorders. There was a main group effect for ACC glutamate (p=0.019). Contrast analyses showed increased glutamate both in children with ASD and OCD compared with controls (p=0.007), but no differences between the two disorders (p=0.770). Dimensional analyses revealed a positive correlation between compulsive behavior (measured with the Repetitive Behavior Scale) and ACC glutamate (rho=0.24, p=0.03). These findings were robust across sites. No differences were found in the striatum. The current findings confirm overlap between ASD and OCD in terms of glutamate involvement. Glutamate concentration in ACC seems to be associated with the severity of compulsive behavior.
South Atlantic circulation in a world ocean model
NASA Astrophysics Data System (ADS)
England, Matthew H.; Garçon, Véronique C.
1994-09-01
The circulation in the South Atlantic Ocean has been simulated within a global ocean general circulation model. Preliminary analysis of the modelled ocean circulation in the region indicates a rather close agreement of the simulated upper ocean flows with conventional notions of the large-scale geostrophic currents in the region. The modelled South Atlantic Ocean witnesses the return flow and export of North Atlantic Deep Water (NADW) at its northern boundary, the inflow of a rather barotropic Antarctic Circumpolar Current (ACC) through the Drake Passage, and the inflow of warm saline Agulhas water around the Cape of Good Hope. The Agulhas leakage amounts to 8.7 Sv, within recent estimates of the mass transport shed westward at the Agulhas retroflection. Topographic steering of the ACC dominates the structure of flow in the circumpolar ocean. The Benguela Current is seen to be fed by a mixture of saline Indian Ocean water (originating from the Agulhas Current) and fresher Subantarctic surface water (originating in the ACC). The Benguela Current is seen to modify its flow and fate with depth; near the surface it flows north-westwards bifurcating most of its transport northward into the North Atlantic Ocean (for ultimate replacement of North Atlantic surface waters lost to the NADW conveyor). Deeper in the water column, more of the Benguela Current is destined to return with the Brazil Current, though northward flows are still generated where the Benguela Current extension encounters the coast of South America. At intermediate levels, these northward currents trace the flow of Antarctic Intermediate Water (AAIW) equatorward, though even more AAIW is seen to recirculate poleward in the subtropical gyre. In spite of the model's rather coarse resolution, some subtle features of the Brazil-Malvinas Confluence are simulated rather well, including the latitude at which the two currents meet. Conceptual diagrams of the recirculation and interocean exchange of thermocline, intermediate and deep waters are constructed from an analysis of flows bound between isothermal and isobaric surfaces. This analysis shows how the return path of NADW is partitioned between a cold water route through the Drake Passage (6.5 Sv), a warm water route involving the Agulhas Current sheeding thermocline water westward (2.5 Sv), and a recirculation of intermediate water originating in the Indian Ocean (1.6 Sv).
Korb, Alexander S.; Hunter, Aimee M.; Cook, Ian A.; Leuchter, Andrew F.
2011-01-01
In treatment trials for Major Depressive Disorder (MDD), early symptom improvement is predictive of eventual clinical response. Clinical response may also be predicted by elevated pretreatment theta (4-7 Hz) current density in the rostral anterior cingulate (rACC) and medial orbitofrontal cortex (mOFC). We investigated the relationship between pretreatment EEG and early improvement in predicting clinical outcome in 72 MDD subjects across three placebo-controlled treatment trials. Subjects were randomized to receive fluoxetine, venlafaxine, or placebo. Theta current density in the rACC and mOFC was computed with Low-Resolution Brain Electromagnetic Tomography (LORETA). An ANCOVA, examining week 8 Hamilton Depression Rating Scale (HamD) percent change, showed a significant effect of week-2-HamD-percent-change, and a significant three-way interaction of week-2-HamD-percent-change × Treatment × rACC. Medication subjects with robust early improvement showed almost no relationship between rACC theta current density and final clinical outcome. However, in subjects with little early improvement, rACC activity showed a strong relationship with clinical outcome. The model examining mOFC showed a trend in the three-way interaction. A combination of pretreatment rACC activity and early symptom improvement may be useful for predicting treatment response. PMID:21546222
The functional integration of the anterior cingulate cortex during conflict processing.
Fan, Jin; Hof, Patrick R; Guise, Kevin G; Fossella, John A; Posner, Michael I
2008-04-01
Although functional activation of the anterior cingulate cortex (ACC) related to conflict processing has been studied extensively, the functional integration of the subdivisions of the ACC and other brain regions during conditions of conflict is still unclear. In this study, participants performed a task designed to elicit conflict processing by using flanker interference on target response while they were scanned using event-related functional magnetic resonance imaging. The physiological response of several brain regions in terms of an interaction between conflict processing and activity of the anterior rostral cingulate zone (RCZa) of the ACC, and the effective connectivity between this zone and other regions were examined using psychophysiological interaction analysis and dynamic causal modeling, respectively. There was significant integration of the RCZa with the caudal cingulate zone (CCZ) of the ACC and other brain regions such as the lateral prefrontal, primary, and supplementary motor areas above and beyond the main effect of conflict and baseline connectivity. The intrinsic connectivity from the RCZa to the CCZ was modulated by the context of conflict. These findings suggest that conflict processing is associated with the effective contribution of the RCZa to the neuronal activity of CCZ, as well as other cortical regions.
MacMaster, Frank P; Carrey, Normand; Langevin, Lisa Marie; Jaworska, Natalia; Crawford, Susan
2014-03-01
Structural abnormalities in frontal, limbic and subcortical regions have been noted in adults with both major depressive disorder (MDD) and bipolar disorder (BD). In the current study, we examined regional brain morphology in youth with MDD and BD as compared to controls. Regional brain volumes were measured in 32 MDD subjects (15.7 ± 2.1 years), 14 BD subjects (16.0 ± 2.4 years) and 22 healthy controls (16.0 ± 2.8 years) using magnetic resonance imaging (MRI). Regions of interest included the hippocampus, dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC), caudate, putamen and thalamus. Volumetric differences between groups were significant (F26,80 = 1.80, p = 0.02). Post-hoc analyses indicated that individuals with MDD showed reduced left hippocampus volumes (p = 0.048) as well as right ACC white and gray matter volumes (p = 0.003; p = 0.01) compared to controls. BD participants also displayed reduced left hippocampal and right/left putamen volumes compared to controls (p < 0.001; p = 0.015; p = 0.046 respectively). Interestingly, right and left ACC white matter volumes were smaller in MDD than in BD participants (p = 0.019; p = 0.045 respectively). No volumetric group differences were observed for the DLPFC and thalamus. Discriminant analysis was able to correctly classify 81.0 % of subjects as having BD or as MDD based on imaging data. Confirmation and extension of our findings requires larger sample sizes. Our findings provide new evidence of distinct, specific regional brain volumetric differences between MDD and BD that may be used to distinguish the two disorders.
Effect of trait anxiety on prefrontal control mechanisms during emotional conflict.
Comte, Magali; Cancel, Aïda; Coull, Jennifer T; Schön, Daniele; Reynaud, Emmanuelle; Boukezzi, Sarah; Rousseau, Pierre-François; Robert, Gabriel; Khalfa, Stéphanie; Guedj, Eric; Blin, Olivier; Weinberger, Daniel R; Fakra, Eric
2015-06-01
Converging evidence points to a link between anxiety proneness and altered emotional functioning, including threat-related biases in selective attention and higher susceptibility to emotionally ambiguous stimuli. However, during these complex emotional situations, it remains unclear how trait anxiety affects the engagement of the prefrontal emotional control system and particularly the anterior cingulate cortex (ACC), a core region at the intersection of the limbic and prefrontal systems. Using an emotional conflict task and functional magnetic resonance imaging (fMRI), we investigated in healthy subjects the relations between trait anxiety and both regional activity and functional connectivity (psychophysiological interaction) of the ACC. Higher levels of anxiety were associated with stronger task-related activation in ACC but with reduced functional connectivity between ACC and lateral prefrontal cortex (LPFC). These results support the hypothesis that when one is faced with emotionally incompatible information, anxiety leads to inefficient high-order control, characterized by insufficient ACC-LPFC functional coupling and increases, possibly compensatory, in activation of ACC. Our findings provide a deeper understanding of the pathophysiology of the neural circuitry underlying anxiety and may offer potential treatment markers for anxiety disorders. © 2015 Wiley Periodicals, Inc.
Newsome, Mary R; Scheibel, Randall S; Mayer, Andrew R; Chu, Zili D; Wilde, Elisabeth A; Hanten, Gerri; Steinberg, Joel L; Lin, Xiaodi; Li, Xiaoqi; Merkley, Tricia L; Hunter, Jill V; Vasquez, Ana C; Cook, Lori; Lu, Hanzhang; Vinton, Kami; Levin, Harvey S
2013-09-01
Outcome of moderate to severe traumatic brain injury (TBI) includes impaired emotion regulation. Emotion regulation has been associated with amygdala and rostral anterior cingulate (rACC). However, functional connectivity between the two structures after injury has not been reported. A preliminary examination of functional connectivity of rACC and right amygdala was conducted in adolescents 2 to 3 years after moderate to severe TBI and in typically developing (TD)control adolescents, with the hypothesis that the TBI adolescents would demonstrate altered functional connectivity in the two regions. Functional connectivity was determined by correlating fluctuations in the blood oxygen level dependent(BOLD) signal of the rACC and right amygdala with that of other brain regions. In the TBI adolescents, the rACC was found to be significantly less functionally connected to medial prefrontal cortices and to right temporal regions near the amygdala (height threshold T = 2.5, cluster level p < .05, FDR corrected), while the right amygdala showed a trend in reduced functional connectivity with the rACC (height threshold T = 2.5, cluster level p = .06, FDR corrected). Data suggest disrupted functional connectivity in emotion regulation regions. Limitations include small sample sizes. Studies with larger sample sizes are necessary to characterize the persistent neural damage resulting from moderate to severe TBI during development.
The Repeat Sequences and Elevated Substitution Rates of the Chloroplast accD Gene in Cupressophytes
Li, Jia; Su, Yingjuan; Wang, Ting
2018-01-01
The plastid accD gene encodes a subunit of the acetyl-CoA carboxylase (ACCase) enzyme. The length of accD gene has been supposed to expand in Cryptomeria japonica, Taiwania cryptomerioides, Cephalotaxus, Taxus chinensis, and Podocarpus lambertii, and the main reason for this phenomenon was the existence of tandemly repeated sequences. However, it is still unknown whether the accD gene length in other cupressophytes has expanded. Here, in order to investigate how widespread this phenomenon was, 18 accD sequences and its surrounding regions of cupressophyte were sequenced and analyzed. Together with 39 GenBank sequence data, our taxon sampling covered all the extant gymnosperm orders. The repetitive elements and substitution rates of accD among 57 gymnosperm species were analyzed, the results show: (1) Reading frame length of accD gene in 18 cupressophytes species has also expanded. (2) Many repetitive elements were identified in accD gene of cupressophyte lineages. (3) The synonymous and non-synonymous substitution rates of accD were accelerated in cupressophytes. (4) accD was located in rearrangement endpoints. These results suggested that repetitive elements may mediate the chloroplast genome rearrangement and accelerated the substitution rates. PMID:29731764
Minzenberg, Michael J; Lesh, Tyler; Niendam, Tara; Yoon, Jong H; Cheng, Yaoan; Rhoades, Remy; Carter, Cameron S
2015-06-01
Suicide is highly prevalent in schizophrenia (SZ), yet it remains unclear how suicide risk factors such as past suicidal ideation or behavior relate to brain function. Circuits modulated by the prefrontal cortex (PFC) are altered in SZ, including in dorsal anterior cingulate cortex (dACC) during conflict-monitoring (an important component of cognitive control), and dACC changes are observed in post-mortem studies of heterogeneous suicide victims. We tested whether conflict-related dACC functional connectivity is associated with past suicidal ideation and behavior in SZ. 32 patients with recent-onset of DSM-IV-TR-defined SZ were evaluated with the Columbia Suicide Severity Rating Scale and functional MRI during cognitive control (AX-CPT) task performance. Group-level regression models relating past history of suicidal ideation or behavior to dACC-seeded functional connectivity during conflict-monitoring controlled for severity of depression, psychosis and impulsivity. Past suicidal ideation was associated with relatively higher functional connectivity of the dACC with the precuneus during conflict-monitoring. Intensity of worst-point past suicidal ideation was associated with relatively higher dACC functional connectivity in medial parietal lobe and striato-thalamic nuclei. In contrast, among those with past suicidal ideation (n = 17), past suicidal behavior was associated with lower conflict-related dACC connectivity with multiple lateral and medial PFC regions, parietal and temporal cortical regions. This study provides unique evidence that recent-onset schizophrenia patients with past suicidal ideation or behavior show altered dACC-based circuit function during conflict-monitoring. Suicidal ideation and suicidal behavior have divergent patterns of associated dACC functional connectivity, suggesting a differing pattern of conflict-related brain dysfunction with these two distinct features of suicide phenomenology. Published by Elsevier Ltd.
Silton, Rebecca Levin; Heller, Wendy; Towers, David N; Engels, Anna S; Spielberg, Jeffrey M; Edgar, J Christopher; Sass, Sarah M; Stewart, Jennifer L; Sutton, Bradley P; Banich, Marie T; Miller, Gregory A
2010-04-15
A network of brain regions has been implicated in top-down attentional control, including left dorsolateral prefrontal cortex (LDLPFC) and dorsal anterior cingulate cortex (dACC). The present experiment evaluated predictions of the cascade-of-control model (Banich, 2009), which predicts that during attentionally-demanding tasks, LDLPFC imposes a top-down attentional set which precedes late-stage selection performed by dACC. Furthermore, the cascade-of-control model argues that dACC must increase its activity to compensate when top-down control by LDLPFC is poor. The present study tested these hypotheses using fMRI and dense-array ERP data collected from the same 80 participants in separate sessions. fMRI results guided ERP source modeling to characterize the time course of activity in LDLPFC and dACC. As predicted, dACC activity subsequent to LDLPFC activity distinguished congruent and incongruent conditions on the Stroop task. Furthermore, when LDLPFC activity was low, the level of dACC activity was related to performance outcome. These results demonstrate that dACC responds to attentional demand in a flexible manner that is dependent on the level of LDLPFC activity earlier in a trial. Overall, results were consistent with the temporal course of regional brain function proposed by the cascade-of-control model. Copyright 2009 Elsevier Inc. All rights reserved.
Bell, Diana; Bell, Achim H; Bondaruk, Jolanta; Hanna, Ehab Y; Weber, Randall S
2016-05-15
Adenoid cystic carcinoma (ACC), 1 of the most common salivary gland malignancies, arises from the intercalated ducts, which are composed of inner ductal epithelial cells and outer myoepithelial cells. The objective of this study was to determine the genomic subtypes of ACC with emphasis on dominant cell type to identify potential specific biomarkers for each subtype and to improve the understanding of this disease. A whole-genome expression study was performed based on 42 primary salivary ACCs and 5 normal salivary glands. RNA from these specimens was subjected to expression profiling with RNA sequencing, and results were analyzed to identify transcripts in epithelial-dominant ACC (E-ACC), myoepithelial-dominant ACC (M-ACC), and all ACC that were expressed differentially compared with the transcripts in normal salivary tissue. In total, the authors identified 430 differentially expressed transcripts that were unique to E-ACC, 392 that were unique to M-ACC, and 424 that were common to both M-ACC and E-ACC. The sets of E-ACC-specific and M-ACC-specific transcripts were sufficiently large to define and differentiate E-ACC from M-ACC. Ingenuity pathway analysis identified known cancer-related genes for 60% of the E-ACC transcripts, 69% of the M-ACC transcripts, and 68% of the transcripts that were common in both E-ACC and M-ACC. Three sets of highly expressed candidate genes-distal-less homeobox 6 (DLX6) for E-ACC; protein keratin 16 (KRT16), SRY box 11 (SOX11), and v-myb avian myeloblastosis viral oncogene homolog (MYB) for M-ACC; and engrailed 1 (EN1) and statherin (STATH), which are common to both E-ACC and M-ACC)-were further validated at the protein level. The current results enabled the authors to identify novel potential therapeutic targets and biomarkers in E-ACC and M-ACC individually, with the implication that EN1, DLX6, and OTX1 (orthodenticle homeobox 1) are potential drivers of these cancers. Cancer 2016;122:1513-22. © 2016 American Cancer Society. © 2016 American Cancer Society.
Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso
2015-01-01
Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies.
Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C.; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso
2015-01-01
Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. PMID:25875640
NASA Astrophysics Data System (ADS)
Strass, Volker H.; Wolf-Gladrow, Dieter; Pakhomov, Evgeny A.; Klaas, Christine
2017-04-01
The Southern Ocean influences earth's climate in many ways. It hosts the largest upwelling region of the world oceans where 80% of deep waters resurface (Morrison et al., 2015). A prominent feature is the broad ring of cold water, the Antarctic Circumpolar Current (ACC), which encircles the Antarctic continent and connects all other oceans. The ACC plays a major role in the global heat and freshwater transports and ocean-wide cycles of chemical and biogenic elements, and harbours a series of unique and distinct ecosystems. Due to the upwelling of deep-water masses in the Antarctic Divergence, there is high supply of natural CO2 as well as macronutrients, leading to the worldwide highest surface nutrient concentrations. Despite the ample macronutrients supply, phytoplankton concentration is generally low, limited either by low micronutrient (iron) availability, insufficient light due to deep wind-mixed layers or grazing by zooplankton, or by the combination of all, varying temporally and regionally.
On the penetration depth of the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Tarakanov, R.
2012-04-01
The Antarctic Circumpolar Current (ACC) is a geostrophic current which encircles Antarctica from west to east. Thus this current is a buffer zone hindering the water exchange (by geostrophic currents) between high and mid-latitudes of the World Ocean in the Southern Hemisphere. The series of the transverse barriers (Phoenix Rift, Hero Ridge, and Shackleton and North Scotia ridges in the region of the Drake Passage and Scotia Sea, Mid-Atlatic Ridge in the Atlantic, Kerguelen Rise in the Indian Ocean, Macquarie Ridge south of New Zealand, and East Pacific Rise) limits the penetration depth of the ACC. The expedition studies of IO RAS in 2003-2011 were concentrated in the Drake Passage. Seven hydrographic sections across the passage and one survey in the central part of the passage were executed during this period. Velocity measurements (by LADCP) on these sections revealed the near-zero transport through the Drake Passage in the water layer 28.26>gamma_n>28.16 which is considered very low layer of circumpolar water and occupied near the bottom. This result, considering quasi-isopycnal spreading of water masses, leads to exclusion of this layer from the circumpolar flow. This conclusion is confirmed by analysis of the data of Russian sections, historical hydrographic database (WODB2009) in the Drake Passage and the Scotia Sea in combination with the satellite altimetry data and taking into account the bottom relief. It shows that the circulation in the aforesaid layer in the Drake Passage and the Scotia Sea is essentially across the ACC jets due to the presence of the Shackleton and North Scotia ridges although both of these ridges are permeable for this layer.
de Krijger, Ronald R; Papathomas, Thomas G
2012-01-01
Adrenocortical carcinoma (ACC) is a rare, heterogeneous malignancy with a poor prognosis. According to WHO classification 2004, ACC variants include oncocytic ACCs, myxoid ACCs and ACCs with sarcomatous areas. Herein, we provide a comprehensive review of these rare subtypes of adrenocortical malignancy and emphasize their clinicopathological features with the aim of elucidating aspects of diagnostic categorization, differential diagnostics and biological behavior. The issue of current terminology, applied to biphasic tumors with pleomorphic, sarcomatous or sarcomatoid elements arising in adrenal cortex, is also discussed. We additionally present emerging evidence concerning the adrenal cortical tumorigenesis and the putative adenoma-carcinoma sequence as well.
Rao, Pulivarthi H; Roberts, Diana; Zhao, Yi-Jue; Bell, Diana; Harris, Charles P; Weber, Randal S; El-Naggar, Adel K
2008-08-15
Adenoid cystic carcinoma (ACC) is a relatively uncommon salivary gland malignancy known for its protean phenotypic features and pernicious clinical behavior. Currently, no effective therapy is available for patients with advanced nonresectable, recurrent, and/or metastatic disease. The purpose of this study is to identify prognostic factors other than tumor stage that can be used to predict the outcome of the patients with ACC. We used comparative genomic hybridization (CGH) to identify copy number aberrations in 53 primary ACCs. Array CGH and fluorescence in situ hybridization analysis was used to validate CGH results on selected cases. We correlated these copy number aberrations with clinicopathologic factors using Pearson's chi2 or by the two-tailed Fisher exact test. The disease-specific survival and disease-free intervals were generated by the Kaplan-Meier product limit method. Chromosomal losses (n = 134) were more frequent than gains (n = 74). The most frequent genetic change was the loss of 1p32-p36 in 44% of the cases followed by 6q23-q27, and 12q12-q14. The most frequently gained chromosomal regions were 8 and 18. Of the chromosomal aberrations, loss of 1p32-p36 was the only abnormality significantly associated with patient's outcome. This study, for the first time, identifies loss of 1p32-p36 as a significant aberration in ACC. Molecular characterization of 1p32-36 region using the available genomic technologies may lead to the identification of new genes critical to the development of novel therapeutic targets for this disease copy number aberration.
NASA Astrophysics Data System (ADS)
Yan, Huiru; Jia, Haihong; Wang, Xiuling; Gao, Hongru; Guo, Xingqi; Xu, Baohua
2013-02-01
Glutathione S-transferases (GSTs) are members of a multifunctional enzyme super family that plays a pivotal role in both insecticide resistance and protection against oxidative stress. In this study, we identified a single-copy gene, AccGSTD, as being a Delta class GST in the Chinese honey bee ( Apis cerana cerana). A predicted antioxidant response element, CREB, was found in the 1,492-bp 5'-flanking region, suggesting that AccGSTD may be involved in oxidative stress response pathways. Real-time PCR and immunolocalization studies demonstrated that AccGSTD exhibited both developmental- and tissue-specific expression patterns. During development, AccGSTD transcript was increased in adults. The AccGSTD expression level was the highest in the honey bee brain. Thermal stress experiments demonstrated that AccGSTD could be significantly upregulated by temperature changes in a time-dependent manner. It is hypothesized that high expression levels might be due to the increased levels of oxidative stress caused by the temperature challenges. Additionally, functional assays of the recombinant AccGSTD protein revealed that AccGSTD has the capability to protect DNA from oxidative damage. Taken together, these data suggest that AccGSTD may be responsible for antioxidant defense in adult honey bees.
Meridional displacement of the Antarctic Circumpolar Current
Gille, Sarah T.
2014-01-01
Observed long-term warming trends in the Southern Ocean have been interpreted as a sign of increased poleward eddy heat transport or of a poleward displacement of the entire Antarctic Circumpolar Current (ACC) frontal system. The two-decade-long record from satellite altimetry is an important source of information for evaluating the mechanisms governing these trends. While several recent studies have used sea surface height contours to index ACC frontal displacements, here altimeter data are instead used to track the latitude of mean ACC transport. Altimetric height contours indicate a poleward trend, regardless of whether they are associated with ACC fronts. The zonally averaged transport latitude index shows no long-term trend, implying that ACC meridional shifts determined from sea surface height might be associated with large-scale changes in sea surface height more than with localized shifts in frontal positions. The transport latitude index is weakly sensitive to the Southern Annular Mode, but is uncorrelated with El Niño/Southern Oscillation. PMID:24891396
Differences in the emergent coding properties of cortical and striatal ensembles
Ma, L.; Hyman, J.M.; Lindsay, A.J.; Phillips, A.G.; Seamans, J.K.
2016-01-01
The function of a given brain region is often defined by the coding properties of its individual neurons, yet how this information is combined at the ensemble level is an equally important consideration. In the present study, multiple neurons from the anterior cingulate cortex (ACC) and the dorsal striatum (DS) were recorded simultaneously as rats performed different sequences of the same three actions. Sequence and lever decoding was remarkably similar on a per-neuron basis in the two regions. At the ensemble level, sequence-specific representations in the DS appeared synchronously but transiently along with the representation of lever location, while these two streams of information appeared independently and asynchronously in the ACC. As a result the ACC achieved superior ensemble decoding accuracy overall. Thus, the manner in which information was combined across neurons in an ensemble determined the functional separation of the ACC and DS on this task. PMID:24974796
Parotid adenoid cystic carcinoma: Retrospective single institute analysis.
Mannelli, Giuditta; Cecconi, Lorenzo; Fasolati, Martina; Santoro, Roberto; Franchi, Alessandro; Gallo, Oreste
Adenoid cystic carcinoma (ACC) is a uncommon salivary malignant tumor. Our aim was to review our experience with parotid ACC, to identify clinical-pathological parameters predictive for outcome. We retrospectively reviewed 228 patients affected by parotid gland carcinomas surgically treated at our Institution. Forty-four ACC were included in this study. Multivariate analysis risk models were built to predict recurrence free probability (RFP), distant recurrence free probability (DRFP), overall survival (OS) and disease free survival (DFS). Twenty-one patients (47.7%) died from ACC and 2.3% for other causes. The 41% presented local-regional recurrence, with a regional-RFP rate of 93%, and the 34% reported distant metastases (DM). The five and ten-year OS rates were 74% and 50%, respectively. Recurrences were mainly influenced by the presence of perineural invasion and nerve paralysis, whilst female gender and age<50 were predictors for good prognosis. Copyright © 2017 Elsevier Inc. All rights reserved.
Alshammari, Abdullah; Eldeib, Omar Jamal; Eldeib, Ahmed Jamal; Saleh, Waleed
2016-01-01
Adenoid cystic carcinoma (ACC) is a rare tumor, described as being one of the most biologically destructive tumors of the head and neck. It is the most common malignancy that affects the minor salivary glands. Lung and bones are the most common regions of ACC distant metastasis. To the best of our knowledge, herein, we report the first ever case of latent isolated sternal metastasis from ACC in a 52-year-old gentleman, who was diagnosed to have ACC of the submandibular gland, excised 10 years ago.
Emotional processing in anterior cingulate and medial prefrontal cortex
Etkin, Amit; Egner, Tobias; Kalisch, Raffael
2010-01-01
Negative emotional stimuli activate a broad network, including the medial prefrontal (mPFC) and anterior cingulate (ACC) cortices. An early influential view dichotomized these regions into dorsal-caudal “cognitive” and ventral-rostral “affective” subdivisions. In this review, we examine a wealth of recent research on negative emotions in animals and humans, using the example of fear/anxiety, and conclude that, contrary to the traditional dichotomy, both subdivisions make key contributions to emotional processing. Specifically, dorsal-caudal regions of the ACC/mPFC are involved in appraisal and expression of negative emotion, while ventral-rostral portions of the ACC/mPFC have a regulatory role with respect to limbic regions involved in generating emotional responses. Moreover, this new framework is broadly consistent with emerging data on other negative and positive emotions. PMID:21167765
Wind-dependent beluga whale dive behavior in Barrow Canyon, Alaska
NASA Astrophysics Data System (ADS)
Stafford, K. M.; Citta, J. J.; Okkonen, S. R.; Suydam, R. S.
2016-12-01
Beluga whales (Delphinapterus leucas) are the most abundant cetacean in the Arctic. The Barrow Canyon region, Alaska, is a hotspot for Pacific Arctic belugas, likely because the oceanographic environment provides reliable foraging opportunities. Fronts are known to promote the concentration of planktonic prey; when Barrow-area winds are weak or from the west, a front associated with the Alaskan Coastal Current (ACC) intensifies. This front is weakened or disrupted when strong easterly winds slow or displace the ACC. To determine if winds influence the diving depth of belugas, we used generalized linear mixed models (GLMM) to examine how the dive behavior of animals instrumented with satellite-linked time-depth recorders varied with wind conditions. When projected along-canyon winds are from the WSW and the front associated with the ACC is enhanced, belugas tend to target shallower depths (10-100 m) associated with the front. In contrast, when strong winds from the ENE displaced the ACC, belugas tended to spend more time at depths >200 m where the Arctic halocline grades into relatively warmer Atlantic Water (AW). The probability of diving to >200 m, the number of dives >200 m, and the amount of time spent below 200 m were all significantly related to along-canyon wind stress (p<0.01). From these results and known relationships between wind stress, currents and frontal structure in Barrow Canyon and the characteristic vertical distribution of Arctic cod, we infer that the probability of belugas targeting different depth regimes is based upon how wind stress affects the relative foraging opportunities between these depth regimes. Belugas are known to target AW throughout the Beaufort Sea; however, this is the first work to show that the probability of targeting the AW layer is related to wind stress.
Tanimizu, Toshiyuki; Kenney, Justin W; Okano, Emiko; Kadoma, Kazune; Frankland, Paul W; Kida, Satoshi
2017-04-12
Social recognition memory is an essential and basic component of social behavior that is used to discriminate familiar and novel animals/humans. Previous studies have shown the importance of several brain regions for social recognition memories; however, the mechanisms underlying the consolidation of social recognition memory at the molecular and anatomic levels remain unknown. Here, we show a brain network necessary for the generation of social recognition memory in mice. A mouse genetic study showed that cAMP-responsive element-binding protein (CREB)-mediated transcription is required for the formation of social recognition memory. Importantly, significant inductions of the CREB target immediate-early genes c-fos and Arc were observed in the hippocampus (CA1 and CA3 regions), medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), and amygdala (basolateral region) when social recognition memory was generated. Pharmacological experiments using a microinfusion of the protein synthesis inhibitor anisomycin showed that protein synthesis in these brain regions is required for the consolidation of social recognition memory. These findings suggested that social recognition memory is consolidated through the activation of CREB-mediated gene expression in the hippocampus/mPFC/ACC/amygdala. Network analyses suggested that these four brain regions show functional connectivity with other brain regions and, more importantly, that the hippocampus functions as a hub to integrate brain networks and generate social recognition memory, whereas the ACC and amygdala are important for coordinating brain activity when social interaction is initiated by connecting with other brain regions. We have found that a brain network composed of the hippocampus/mPFC/ACC/amygdala is required for the consolidation of social recognition memory. SIGNIFICANCE STATEMENT Here, we identify brain networks composed of multiple brain regions for the consolidation of social recognition memory. We found that social recognition memory is consolidated through CREB-meditated gene expression in the hippocampus, medial prefrontal cortex, anterior cingulate cortex (ACC), and amygdala. Importantly, network analyses based on c-fos expression suggest that functional connectivity of these four brain regions with other brain regions is increased with time spent in social investigation toward the generation of brain networks to consolidate social recognition memory. Furthermore, our findings suggest that hippocampus functions as a hub to integrate brain networks and generate social recognition memory, whereas ACC and amygdala are important for coordinating brain activity when social interaction is initiated by connecting with other brain regions. Copyright © 2017 the authors 0270-6474/17/374103-14$15.00/0.
Vékony, Hedy; Ylstra, Bauke; Wilting, Saskia M; Meijer, Gerrit A; van de Wiel, Mark A; Leemans, C René; van der Waal, Isaäc; Bloemena, Elisabeth
2007-06-01
Adenoid cystic carcinoma (ACC) is a malignant salivary gland tumor with a high mortality rate due to late, distant metastases. This study aimed at unraveling common genetic abnormalities associated with ACC. Additionally, chromosomal changes were correlated with patient characteristics and survival. Microarray-based comparative genomic hybridization was done to a series of 18 paraffin-embedded primary ACCs using a genome-wide scanning BAC array. A total of 238 aberrations were detected, representing more gains than losses (205 versus 33, respectively). Most frequent gains (>60%) were observed at 9q33.3-q34.3, 11q13.3, 11q23.3, 19p13.3-p13.11, 19q12-q13.43, 21q22.3, and 22q13.33. These loci harbor numerous growth factor [fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF)] and growth factors receptor (FGFR3 and PDGFRbeta) genes. Gains at the FGF(R) regions occurred significantly more frequently in the recurred/metastasized ACCs compared with indolent ACCs. Furthermore, patients with 17 or more chromosomal aberrations had a significantly less favorable outcome than patients with fewer chromosomal aberrations (log-rank = 5.2; P = 0.02). Frequent DNA copy number gains at loci of growth factors and their receptors suggest their involvement in ACC initiation and progression. Additionally, the presence of FGFR3 and PDGFRbeta in increased chromosomal regions suggests a possible role for autocrine stimulation in ACC tumorigenesis.
Linzarini, Adriano; Dollfus, Sonia; Etard, Olivier; Orliac, François; Houdé, Olivier
2018-01-01
Abstract Inhibitory control (IC) is a core executive function that enables humans to resist habits, temptations, or distractions. IC efficiency in childhood is a strong predictor of academic and professional success later in life. Based on analysis of the sulcal pattern, a qualitative feature of cortex anatomy determined during fetal life and stable during development, we searched for evidence that interindividual differences in IC partly trace back to prenatal processes. Using anatomical magnetic resonance imaging (MRI), we analyzed the sulcal pattern of two key regions of the IC neural network, the dorsal anterior cingulate cortex (ACC) and the inferior frontal cortex (IFC), which limits the inferior frontal gyrus. We found that the sulcal pattern asymmetry of both the ACC and IFC contributes to IC (Stroop score) in children and adults: participants with asymmetrical ACC or IFC sulcal patterns had better IC efficiency than participants with symmetrical ACC or IFC sulcal patterns. Such additive effects of IFC and ACC sulcal patterns on IC efficiency suggest that distinct early neurodevelopmental mechanisms targeting different brain regions likely contribute to IC efficiency. This view shares some analogies with the “common variant–small effect” model in genetics, which states that frequent genetic polymorphisms have small effects but collectively account for a large portion of the variance. Similarly, each sulcal polymorphism has a small but additive effect: IFC and ACC sulcal patterns, respectively, explained 3% and 14% of the variance of the Stroop interference scores. PMID:29527565
Tissier, Cloélia; Linzarini, Adriano; Allaire-Duquette, Geneviève; Mevel, Katell; Poirel, Nicolas; Dollfus, Sonia; Etard, Olivier; Orliac, François; Peyrin, Carole; Charron, Sylvain; Raznahan, Armin; Houdé, Olivier; Borst, Grégoire; Cachia, Arnaud
2018-01-01
Inhibitory control (IC) is a core executive function that enables humans to resist habits, temptations, or distractions. IC efficiency in childhood is a strong predictor of academic and professional success later in life. Based on analysis of the sulcal pattern, a qualitative feature of cortex anatomy determined during fetal life and stable during development, we searched for evidence that interindividual differences in IC partly trace back to prenatal processes. Using anatomical magnetic resonance imaging (MRI), we analyzed the sulcal pattern of two key regions of the IC neural network, the dorsal anterior cingulate cortex (ACC) and the inferior frontal cortex (IFC), which limits the inferior frontal gyrus. We found that the sulcal pattern asymmetry of both the ACC and IFC contributes to IC (Stroop score) in children and adults: participants with asymmetrical ACC or IFC sulcal patterns had better IC efficiency than participants with symmetrical ACC or IFC sulcal patterns. Such additive effects of IFC and ACC sulcal patterns on IC efficiency suggest that distinct early neurodevelopmental mechanisms targeting different brain regions likely contribute to IC efficiency. This view shares some analogies with the "common variant-small effect" model in genetics, which states that frequent genetic polymorphisms have small effects but collectively account for a large portion of the variance. Similarly, each sulcal polymorphism has a small but additive effect: IFC and ACC sulcal patterns, respectively, explained 3% and 14% of the variance of the Stroop interference scores.
Colic, Lejla; Li, Meng; Demenescu, Liliana Ramona; Li, Shija; Müller, Iris; Richter, Anni; Behnisch, Gusalija; Seidenbecher, Constanze I; Speck, Oliver; Schott, Björn H; Stork, Oliver; Walter, Martin
2018-05-30
Anxiety disorders are common and debilitating conditions with higher prevalence in women. However, factors that predispose women to anxiety phenotypes are not clarified. Here we investigated potential contribution of the single nucleotide polymorphism rs2236418 in GAD2 gene to changes in regional inhibition/excitation balance, anxiety-like traits, and related neural activity in both sexes. One hundred and five healthy individuals were examined with high-field (7T) multimodal magnetic resonance imaging (MRI); including resting-state functional MRI in combination with assessment of GABA and glutamate (Glu) levels via MR spectroscopy. Regional GABA/Glu levels in anterior cingulate cortex (ACC) subregions were assessed as mediators of gene-personality interaction for the trait harm avoidance and moderation by sex was tested. In AA homozygotes, with putatively lower GAD2 promoter activity, we observed increased intrinsic neuronal activity and higher inhibition/excitation balance in pregenual ACC (pgACC) compared with G carriers. The pgACC drove a significant interaction of genotype, region, and sex, where inhibition/excitation balance was significantly reduced only in female AA carriers. This finding was specific for rs2236418 as other investigated single nucleotide polymorphisms of the GABA synthesis related enzymes ( GAD1 , GAD2 , and GLS ) were not significant. Furthermore, only in women there was a negative association of pgACC GABA/Glu ratios with harm avoidance. A moderated-mediation model revealed that pgACC GABA/Glu also mediated the association between the genotype variant and level of harm avoidance, dependent on sex. Our data thus provide new insights into the neurochemical mechanisms that control emotional endophenotypes in humans and constitute predisposing factors for the development of anxiety disorders in women. SIGNIFICANCE STATEMENT Anxiety disorders are among the most common and burdensome psychiatric disorders, with higher prevalence rates in women. The causal mechanisms are, however, poorly understood. In this study we propose a neurobiological basis that could help to explain female bias of anxiety endophenotypes. Using magnetic resonance brain imaging and personality questionnaires we show an interaction of the genetic variation rs2236418 in the GAD2 gene and sex on GABA/glutamate (Glu) balance in the pregenual anterior cingulate cortex (pgACC), a region previously connected to affect regulation and anxiety disorders. The GAD2 gene polymorphism further influenced baseline neuronal activity in the pgACC. Importantly, GABA/Glu was shown to mediate the relationship between the genetic variant and harm avoidance, however, only in women. Copyright © 2018 the authors 0270-6474/18/385068-11$15.00/0.
Pathways of upwelling deep waters to the surface of the Southern Ocean
NASA Astrophysics Data System (ADS)
Tamsitt, Veronica; Drake, Henri; Morrison, Adele; Talley, Lynne; Dufour, Carolina; Gray, Alison; Griffies, Stephen; Mazloff, Matthew; Sarmiento, Jorge; Wang, Jinbo; Weijer, Wilbert
2017-04-01
Upwelling of Atlantic, Indian and Pacific deep waters to the sea surface in the Southern Ocean closes the global overturning circulation and is fundamentally important for oceanic uptake of anthropogenic carbon and heat, nutrient resupply for sustaining oceanic biological production, and the melt rate of ice shelves. Here we go beyond the two-dimensional view of Southern Ocean upwelling, to show detailed Southern Ocean upwelling pathways in three dimensions, using hydrographic observations and particle tracking in high-resolution ocean and climate models. The northern deep waters enter the Antarctic Circumpolar Current (ACC) via narrow southward currents along the boundaries of the three ocean basins, before spiraling southeastward and upward through the ACC. Upwelling is greatly enhanced at five major topographic features, associated with vigorous mesoscale eddy activity. Deep water reaches the upper ocean predominantly south of the southern ACC boundary, with a spatially nonuniform distribution, regionalizing warm water supply to Antarctic ice shelves and the delivery of nutrient and carbon-rich water to the sea surface. The timescale for half of the deep water to upwell from 30°S to the mixed layer is on the order of 60-90 years, which has important implications for the timescale for signals to propagate through the deep ocean. In addition, we quantify the diabatic transformation along particle trajectories, to identify where diabatic processes are important along the upwelling pathways.
Fox, Glenn R.; Sobhani, Mona; Aziz-Zadeh, Lisa
2013-01-01
How does witnessing a hateful person in pain compare to witnessing a likable person in pain? The current study compared the brain bases for how we perceive likable people in pain with those of viewing hateful people in pain. While social bonds are built through sharing the plight and pain of others in the name of empathy, viewing a hateful person in pain also has many potential ramifications. In this functional Magnetic Resonance Imaging (fMRI) study, Caucasian Jewish male participants viewed videos of (1) disliked, hateful, anti-Semitic individuals, and (2) liked, non-hateful, tolerant individuals in pain. The results showed that, compared with viewing liked people, viewing hateful people in pain elicited increased responses in regions associated with observation of physical pain (the insular cortex, the anterior cingulate cortex (ACC), and the somatosensory cortex), reward processing (the striatum), and frontal regions associated with emotion regulation. Functional connectivity analyses revealed connections between seed regions in the left ACC and right insular cortex with reward regions, the amygdala, and frontal regions associated with emotion regulation. These data indicate that regions of the brain active while viewing someone in pain may be more active in response to the danger or threat posed by witnessing the pain of a hateful individual more so than the desire to empathize with a likable person's pain. PMID:24167496
Why is there net surface heating over the Antarctic Circumpolar Current?
NASA Astrophysics Data System (ADS)
Czaja, Arnaud; Marshall, John
2015-05-01
Using a combination of atmospheric reanalysis data, climate model outputs and a simple model, key mechanisms controlling net surface heating over the Southern Ocean are identified. All data sources used suggest that, in a streamline-averaged view, net surface heating over the Antarctic Circumpolar Current (ACC) is a result of net accumulation of solar radiation rather than a result of heat gain through turbulent fluxes (the latter systematically cool the upper ocean). It is proposed that the fraction of this net radiative heat gain realized as net ACC heating is set by two factors. First, the sea surface temperature at the southern edge of the ACC. Second, the relative strength of the negative heatflux feedbacks associated with evaporation at the sea surface and advection of heat by the residual flow in the oceanic mixed layer. A large advective feedback and a weak evaporative feedback maximize net ACC heating. It is shown that the present Southern Ocean and its circumpolar current are in this heating regime.
Functional, structural, and emotional correlates of impaired insight in cocaine addiction
Moeller, Scott J.; Konova, Anna B.; Parvaz, Muhammad A.; Tomasi, Dardo; Lane, Richard D.; Fort, Carolyn; Goldstein, Rita Z.
2014-01-01
Context Individuals with cocaine use disorder (CUD) have difficulty monitoring ongoing behavior, possibly stemming from dysfunction of brain regions subserving insight and self-awareness [e.g., anterior cingulate cortex (ACC)]. Objective To test the hypothesis that CUD with impaired insight (iCUD) would show abnormal (A) ACC activity during error processing, assessed with functional magnetic resonance imaging during a classic inhibitory control task; (B) ACC gray matter integrity assessed with voxel-based morphometry; and (C) awareness of one’s own emotional experiences, assessed with the Levels of Emotional Awareness Scale (LEAS). Using a previously validated probabilistic choice task, we grouped 33 CUD according to insight [iCUD: N=15; unimpaired insight CUD: N=18]; we also studied 20 healthy controls, all with unimpaired insight. Design Multimodal imaging design. Setting Clinical Research Center at Brookhaven National Laboratory. Participants Thirty-three CUD and 20 healthy controls. Main Outcome Measure Functional magnetic resonance imaging, voxel-based morphometry, LEAS, and drug use variables. Results Compared with the other two study groups, iCUD showed lower (A) error-induced rostral ACC (rACC) activity as associated with more frequent cocaine use; (B) gray matter within the rACC; and (C) LEAS scores. Conclusions These results point to rACC functional and structural abnormalities, and diminished emotional awareness, in a subpopulation of CUD characterized by impaired insight. Because the rACC has been implicated in appraising the affective/motivational significance of errors and other types of self-referential processing, functional and structural abnormalities in this region could result in lessened concern (frequently ascribed to minimization and denial) about behavioral outcomes that could potentially culminate in increased drug use. Treatments targeting this CUD subgroup could focus on enhancing the salience of errors (e.g., lapses). PMID:24258223
Acute Radiation Hypotension in the Rabbit: a Model for the Human Radiation Shock Syndrome.
NASA Astrophysics Data System (ADS)
Makale, Milan Theodore
This study has shown that total body irradiation (TBI) of immature (40 to 100 day old) rabbits leads to an acute fall in mean arterial pressure (MAP) 30 to 90 minutes after exposure, which takes no more than about three minutes, and often results in pressures which are less than 50% of the lowest pre-exposure MAP. This is termed acute cardiovascular collapse (ACC). ACC is often accompanied by ECG T-wave elevation, a sharp rise in ear temperature, labored breathing, pupillary constriction, bladder emptying, and loss of abdominal muscle tone. About 73% of 40 to 100 day rabbits exhibit ACC; the others and most older rabbits display gradual pressure reductions (deliberate hypotension) which may be profound, and which may be accompanied by the same changes associated with ACC. ACC and deliberate hypotension occurred in rabbits cannulated in the dorsal aorta, and in non-operated animals. The decline in MAP for all 40 to 100 day cannulated rabbits (deliberate and ACC responders) is 55.4%. The experiments described below only involved 40 to 100 day cannulated TBI rabbits. Heart region irradiation resulted in an average MAP decline of 29.1%, with 1/15 rabbits showing ACC. Heart shielding during TBI reduced the decline in MAP to 19%, with 1/10 rabbits experiencing ACC. These results imply that the heart region, which includes the heart, part of the lungs, neural receptors, roots of the systemic vessels, and the blood, is a sensitive target. Bilateral vagotomy reduced the decline in MAP to 24.9%, and abolished ACC. Atropine (6 mg/kg) reduced the frequency of ACC to 26%, and the decline in MAP to 41.4%. In 11/13 rabbits the voltage generated by left vagal transmission rose after TBI. The vagi appear to participate in radiation hypotension. Heart shielding together with bilateral vagotomy reduced the decline in MAP to only 9.9%, with no ACC responders. The mean right ventricular pressure (MRVP) rose after TBI in 8/10 rabbits. In animals which displayed either ACC or steep deliberate hypotension, the MRVP rose sharply prior to the rapid decline in MAP. This suggests that the pulmonary blood flow was impeded, possibly causing right heart failure (cor pulmonale), and consequent cardiovascular collapse.
Parikh, Punam P; Rubio, Gustavo A; Farra, Josefina C; Lew, John I
2017-08-25
Current adrenalectomy outcomes for functional adrenocortical carcinoma (ACC) remain unclear. This study examines nationwide in-hospital post-adrenalectomy outcomes for ACC. A retrospective analysis of the Nationwide Inpatient Sample database (2006-2011) to identify unilateral adrenalectomy patients for functional or nonfunctional ACC was performed. Patient demographics, comorbidities and postoperative outcomes were evaluated by t-test, Chi-square and multivariate regression. Of 2199 patients who underwent adrenalectomy, 87% had nonfunctional and 13% had functional ACC (86% hypercortisolism, 16% hyperaldosteronism, 4% hyperandrogenism). Functional ACC patients had significantly more comorbidities, and experienced certain postoperative complications more frequently including wound issues, adrenocortical insufficiency and acute kidney injury with longer hospital stay compared to nonfunctional ACC (P < 0.01). On multivariate analysis, functional ACC was an independent prognosticator for wound complications (28.1, 95%CI 4.59-176.6). Patients with functional ACC manifest significant comorbidities with certain in-hospital complications. Such high-risk patients require appropriate preoperative medical optimization prior to adrenalectomy. Patients with functional adrenocortical carcinoma (ACC) have significant preoperative comorbidities and experience higher rates of certain postoperative complications including wound complications, hematoma formation, adrenal insufficiency, pulmonary embolism and acute kidney injury. Functional ACC patients also necessitate longer hospitalizations. These patients should undergo appropriate preoperative counseling in preparation for adrenalectomy. Copyright © 2017 Elsevier Inc. All rights reserved.
Fujimoto, Toshiro; Okumura, Eiichi; Kodabashi, Atsushi; Takeuchi, Kouzou; Otsubo, Toshiaki; Nakamura, Katsumi; Yatsushiro, Kazutaka; Sekine, Masaki; Kamiya, Shinichiro; Shimooki, Susumu; Tamura, Toshiyo
2016-01-01
We studied sex-related differences in gamma oscillation during an auditory oddball task, using magnetoencephalography and electroencephalography assessment of imaginary coherence (IC). We obtained a statistical source map of event-related desynchronization (ERD) / event-related synchronization (ERS), and compared females and males regarding ERD / ERS. Based on the results, we chose respectively seed regions for IC determinations in low (30-50 Hz), mid (50-100 Hz) and high gamma (100-150 Hz) bands. In males, ERD was increased in the left posterior cingulate cortex (CGp) at 500 ms in the low gamma band, and in the right caudal anterior cingulate cortex (cACC) at 125 ms in the mid-gamma band. ERS was increased in the left rostral anterior cingulate cortex (rACC) at 375 ms in the high gamma band. We chose the CGp, cACC and rACC as seeds, and examined IC between the seed and certain target regions using the IC map. IC changes depended on the height of the gamma frequency and the time window in the gamma band. Although IC in the mid and high gamma bands did not show sex-specific differences, IC at 30-50 Hz in males was increased between the left rACC and the frontal, orbitofrontal, inferior temporal and fusiform target regions. Increased IC in males suggested that males may acomplish the task constructively, analysingly, emotionally, and by perfoming analysis, and that information processing was more complicated in the cortico-cortical circuit. On the other hand, females showed few differences in IC. Females planned the task with general attention and economical well-balanced processing, which was explained by the higher overall functional cortical connectivity. CGp, cACC and rACC were involved in sex differences in information processing and were likely related to differences in neuroanatomy, hormones and neurotransmitter systems.
Neural response to reward anticipation in those with depression with and without panic disorder.
Gorka, Stephanie M; Huggins, Ashley A; Fitzgerald, Daniel A; Nelson, Brady D; Phan, K Luan; Shankman, Stewart A
2014-08-01
One of the hallmark features of major depressive disorder (MDD) is reduced reward anticipation. There have been mixed findings in the literature as to whether reward anticipation deficits in MDD are related to diminished mesolimbic activation and/or enhanced dorsal anterior cingulate activation (dACC). One of the reasons for these mixed findings is that these studies have typically not addressed the role of comorbid anxiety, a class of disorders which frequently co-occur with depression and have a common neurobiology. The aim of the current study was to examine group differences in neural responses to reward anticipation in 40 adults with either: (1) current MDD with no lifetime diagnosis of an anxiety disorder (MDD-only), (2) current MDD with comorbid panic disorder (MDD-PD), or (3) no lifetime diagnosis of psychopathology. All participants completed a passive slot machine task during a functional magnetic resonance imaging (fMRI) scan. Analyses indicated that there were no group differences in activation of mesolimbic reward regions; however, the MDD-only group exhibited greater dACC activation during the anticipation of rewards compared with the healthy controls and the comorbid MDD-PD group (who did not differ from each other). The sample size was small which limits generalizability. These findings provide preliminary support for the role of hyperactive dACC functioning in reduced reward anticipation in MDD. They also indicate that comorbid anxiety may alter the association between MDD and neural responding to reward anticipation. Copyright © 2014 Elsevier B.V. All rights reserved.
Yoshimura, Shinpei; Okamoto, Yasumasa; Matsunaga, Miki; Onoda, Keiichi; Okada, Go; Kunisato, Yoshihiko; Yoshino, Atsuo; Ueda, Kazutaka; Suzuki, Shin-Ichi; Yamawaki, Shigeto
2017-01-15
Depression is characterized by negative self-cognition. Our previous study (Yoshimura et al. 2014) revealed changes in brain activity after cognitive behavioral therapy (CBT) for depression, but changes in functional connectivity were not assessed. This study included 29 depressive patients and 15 healthy control participants. Functional Magnetic Resonance Imaging was used to investigate possible CBT-related functional connectivity changes associated with negative emotional self-referential processing. Depressed and healthy participants (overlapping with our previous study, Yoshimura et al. 2014) were included. We defined a seed region (medial prefrontal cortex) and coupled region (ACC) based on our previous study, and we examined changes in MPFC-ACC functional connectivity from pretreatment to posttreatment. CBT was associated with reduced functional connectivity between the MPFC and ACC. Symptom change with CBT was positively correlated with change in MPFC-ACC functional connectivity. Patients received pharmacotherapy including antidepressant. The present sample size was quite small and more study is needed. Statistical threshold in fMRI analysis was relatively liberal. CBT for depression may disrupt MPFC-ACC connectivity, with associated improvements in depressive symptoms and dysfunctional cognition. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Williams, R. T.; Geddes, Q. A.; Baker, A.; Gao, M.; Voelker, E.; Oluwakonyinsola, A.
2013-12-01
The Amboseli Conservation Centre (ACC) has been gathering comprehensive field data for 47 years within the Amboseli Basin near Mount Kilimanjaro in Kenya. Over the past half century, the region has suffered from near complete deforestation and continues to suffer from land degradation due to the increasingly sedentary and segregated human and animal concentrations. Overall, Kenya has experienced a loss of over 50% of biodiversity countrywide since 1977. 30% of remaining biodiversity is found in protected areas, which take up only 8% of the country's total land area. The Amboseli National Park has been identified as having the highest level of habitat irreplaceability of all 33 protected areas in the Somali-Masai Ecoregion. The successional cycles between woody vegetation and grassland affect levels of biodiversity in the region, and are largely driven by the grazing and migratory activities of elephants, as well as human land use and land management practices. Understanding the dynamics of land cover change as a continuum is therefore critical to framing conservation objectives. Currently, few land cover classifications derived from remote sensing are consistent with ACC field data, specifically in terms of differentiation between woody versus grassland vegetation. The ACC is interested in refining these distinctions in the Basin and across the Kenya-Tanzania borderlands and identifying which vegetation types are suffering from degradation and where. Therefore, the goal of this project is to 1) establish phenological profiles of differing vegetation in the Kenya-Tanzania borderlands and 2) characterize trends and drought resilience across the landscape. By analyzing MODIS vegetation indices in 8-day time steps from 2002 to 2012, this study establishes phenological profiles of primary vegetation cover classes including woodlands, bushlands, grasslands, and swamps and identifies areas that are drought-resistant or drought-sensitive at a large scale. By enhancing the ACC's ability to explore and communicate important biological distinctions based on phenology, the project will not only develop a useful tool for the ACC, but further a variety of their conservation and research goals.
Kimura, Y; Miyake, R; Tokumasu, Y; Sato, M
2000-10-01
We have cloned a DNA fragment from a genomic library of Myxococcus xanthus using an oligonucleotide probe representing conserved regions of biotin carboxylase subunits of acetyl coenzyme A (acetyl-CoA) carboxylases. The fragment contained two open reading frames (ORF1 and ORF2), designated the accB and accA genes, capable of encoding a 538-amino-acid protein of 58.1 kDa and a 573-amino-acid protein of 61.5 kDa, respectively. The protein (AccA) encoded by the accA gene was strikingly similar to biotin carboxylase subunits of acetyl-CoA and propionyl-CoA carboxylases and of pyruvate carboxylase. The putative motifs for ATP binding, CO(2) fixation, and biotin binding were found in AccA. The accB gene was located upstream of the accA gene, and they formed a two-gene operon. The protein (AccB) encoded by the accB gene showed high degrees of sequence similarity with carboxyltransferase subunits of acetyl-CoA and propionyl-CoA carboxylases and of methylmalonyl-CoA decarboxylase. Carboxybiotin-binding and acyl-CoA-binding domains, which are conserved in several carboxyltransferase subunits of acyl-CoA carboxylases, were found in AccB. An accA disruption mutant showed a reduced growth rate and reduced acetyl-CoA carboxylase activity compared with the wild-type strain. Western blot analysis indicated that the product of the accA gene was a biotinylated protein that was expressed during the exponential growth phase. Based on these results, we propose that this M. xanthus acetyl-CoA carboxylase consists of two subunits, which are encoded by the accB and accA genes, and occupies a position between prokaryotic and eukaryotic acetyl-CoA carboxylases in terms of evolution.
Ali, S; Charles, T C; Glick, B R
2012-11-01
The ability of 1-aminocyclopropane-1-carboxylate (ACC) deaminase-containing plant growth-promoting bacterial (PGPB) endophytes Pseudomonas fluorescens YsS6 and Pseudomonas migulae 8R6, their ACC deaminase minus mutants and the rhizospheric plant growth-promoting bacterium Pseudomonas putida UW4 to delay the senescence of mini carnation cut flowers was assessed. Fresh cut flowers were incubated with either a bacterial cell suspension, the ethylene precursor ACC, the ethylene inhibitor l-α-(aminoethoxyvinyl)-glycine or 0·85% NaCl at room temperature for 11 days. Levels of flower senescence were recorded every other day. To verify the presence of endophytes inside the plant tissues, scanning electron microscopy was performed. Among all treatments, flowers treated with wild-type ACC deaminase-containing endophytic strains exhibited the most significant delay in flower senescence, while flowers treated with the ACC deaminase minus mutants senesced at a rate similar to the control. Flowers treated with Ps. putida UW4 senesced more rapidly than untreated control flowers. The only difference between wild-type and mutant bacterial endophytes was ACC deaminase activity so that it may be concluded that this enzyme is directly responsible for the significant delay in flower senescence. Despite containing ACC deaminase activity, Ps. putida UW4 is not taken up by the cut flowers and therefore has no effect on prolonging their shelf life. The world-wide cut flower industry currently uses expensive and potentially environmentally dangerous chemical inhibitors of ethylene to prolong the shelf life of cut flowers. The use of PGPB endophytes with ACC deaminase activity has the potential to replace the chemicals that are currently used by the cut flower industry. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
Anterior cingulate cortex activity can be independent of response conflict in Stroop-like tasks.
Roelofs, Ardi; van Turennout, Miranda; Coles, Michael G H
2006-09-12
Cognitive control includes the ability to formulate goals and plans of action and to follow these while facing distraction. Previous neuroimaging studies have shown that the presence of conflicting response alternatives in Stroop-like tasks increases activity in dorsal anterior cingulate cortex (ACC), suggesting that the ACC is involved in cognitive control. However, the exact nature of ACC function is still under debate. The prevailing conflict detection hypothesis maintains that the ACC is involved in performance monitoring. According to this view, ACC activity reflects the detection of response conflict and acts as a signal that engages regulative processes subserved by lateral prefrontal brain regions. Here, we provide evidence from functional MRI that challenges this view and favors an alternative view, according to which the ACC has a role in regulation itself. Using an arrow-word Stroop task, subjects responded to incongruent, congruent, and neutral stimuli. A critical prediction made by the conflict detection hypothesis is that ACC activity should be increased only when conflicting response alternatives are present. Our data show that ACC responses are larger for neutral than for congruent stimuli, in the absence of response conflict. This result demonstrates the engagement of the ACC in regulation itself. A computational model of Stroop-like performance instantiating a version of the regulative hypothesis is shown to account for our findings.
Altered Neural Processing to Social Exclusion in Young Adult Marijuana Users
Gilman, Jodi M.; Curran, Max T.; Calderon, Vanessa; Schuster, Randi M.; Evins, A. Eden
2015-01-01
Previous studies have reported that peer groups are one of the most important predictors of adolescent and young adult marijuana use, and yet the neural correlates of social processing in marijuana users have not yet been studied. In the current study, marijuana-using young adults (n = 20) and non-using controls (n = 22) participated in a neuroimaging social exclusion task called Cyberball, a computerized ball-tossing game in which the participant is excluded from the game after a pre-determined number of ball tosses. Controls, but not marijuana users, demonstrated significant activation in the insula, a region associated with negative emotion, when being excluded from the game. Both groups demonstrated activation of the ventral anterior cingulate cortex (vACC), a region associated with affective monitoring, during peer exclusion. Only the marijuana group showed a correlation between vACC activation and scores on a self-report measure of peer conformity. This study indicates that marijuana users show atypical neural processing of social exclusion, which may be either caused by, or the result of, regular marijuana use. PMID:26977454
NASA Technical Reports Server (NTRS)
Fu, L.-L.; Chelton, D. B.
1985-01-01
A new method is developed for studying large-scale temporal variability of ocean currents from satellite altimetric sea level measurements at intersections (crossovers) of ascending and descending orbit ground tracks. Using this method, sea level time series can be constructed from crossover sea level differences in small sample areas where altimetric crossovers are clustered. The method is applied to Seasat altimeter data to study the temporal evolution of the Antarctic Circumpolar Current (ACC) over the 3-month Seasat mission (July-October 1978). The results reveal a generally eastward acceleration of the ACC around the Southern Ocean with meridional disturbances which appear to be associated with bottom topographic features. This is the first direct observational evidence for large-scale coherence in the temporal variability of the ACC. It demonstrates the great potential of satellite altimetry for synoptic observation of temporal variability of the world ocean circulation.
van Duijvenvoorde, A C K; Achterberg, M; Braams, B R; Peters, S; Crone, E A
2016-01-01
The current study aimed to test a dual-systems model of adolescent brain development by studying changes in intrinsic functional connectivity within and across networks typically associated with cognitive-control and affective-motivational processes. To this end, resting-state and task-related fMRI data were collected of 269 participants (ages 8-25). Resting-state analyses focused on seeds derived from task-related neural activation in the same participants: the dorsal lateral prefrontal cortex (dlPFC) from a cognitive rule-learning paradigm and the nucleus accumbens (NAcc) from a reward-paradigm. Whole-brain seed-based resting-state analyses showed an age-related increase in dlPFC connectivity with the caudate and thalamus, and an age-related decrease in connectivity with the (pre)motor cortex. nAcc connectivity showed a strengthening of connectivity with the dorsal anterior cingulate cortex (ACC) and subcortical structures such as the hippocampus, and a specific age-related decrease in connectivity with the ventral medial PFC (vmPFC). Behavioral measures from both functional paradigms correlated with resting-state connectivity strength with their respective seed. That is, age-related change in learning performance was mediated by connectivity between the dlPFC and thalamus, and age-related change in winning pleasure was mediated by connectivity between the nAcc and vmPFC. These patterns indicate (i) strengthening of connectivity between regions that support control and learning, (ii) more independent functioning of regions that support motor and control networks, and (iii) more independent functioning of regions that support motivation and valuation networks with age. These results are interpreted vis-à-vis a dual-systems model of adolescent brain development. Copyright © 2015. Published by Elsevier Inc.
Scheinost, Dustin; Holmes, Sophie E; DellaGioia, Nicole; Schleifer, Charlie; Matuskey, David; Abdallah, Chadi G; Hampson, Michelle; Krystal, John H; Anticevic, Alan; Esterlis, Irina
2018-01-01
Converging evidence suggests that major depressive disorder (MDD) affects multiple large-scale brain networks. Analyses of the correlation or covariance of regional brain structure and function applied to structural and functional MRI data may provide insights into systems-level organization and structure-to-function correlations in the brain in MDD. This study applied tensor-based morphometry and intrinsic connectivity distribution to identify regions of altered volume and intrinsic functional connectivity in data from unmedicated individuals with MDD (n=17) and healthy comparison participants (HC, n=20). These regions were then used as seeds for exploratory anatomical covariance and connectivity analyses. Reduction in volume in the anterior cingulate cortex (ACC) and lower structural covariance between the ACC and the cerebellum were observed in the MDD group. Additionally, individuals with MDD had significantly lower whole-brain intrinsic functional connectivity in the medial prefrontal cortex (mPFC). This mPFC region showed altered connectivity to the ventral lateral PFC (vlPFC) and local circuitry in MDD. Global connectivity in the ACC was negatively correlated with reported depressive symptomatology. The mPFC–vlPFC connectivity was positively correlated with depressive symptoms. Finally, we observed increased structure-to-function correlation in the PFC/ACC in the MDD group. Although across all analysis methods and modalities alterations in the PFC/ACC were a common finding, each modality and method detected alterations in subregions belonging to distinct large-scale brain networks. These exploratory results support the hypothesis that MDD is a systems level disorder affecting multiple brain networks located in the PFC and provide new insights into the pathophysiology of this disorder. PMID:28944772
Scheinost, Dustin; Holmes, Sophie E; DellaGioia, Nicole; Schleifer, Charlie; Matuskey, David; Abdallah, Chadi G; Hampson, Michelle; Krystal, John H; Anticevic, Alan; Esterlis, Irina
2018-04-01
Converging evidence suggests that major depressive disorder (MDD) affects multiple large-scale brain networks. Analyses of the correlation or covariance of regional brain structure and function applied to structural and functional MRI data may provide insights into systems-level organization and structure-to-function correlations in the brain in MDD. This study applied tensor-based morphometry and intrinsic connectivity distribution to identify regions of altered volume and intrinsic functional connectivity in data from unmedicated individuals with MDD (n=17) and healthy comparison participants (HC, n=20). These regions were then used as seeds for exploratory anatomical covariance and connectivity analyses. Reduction in volume in the anterior cingulate cortex (ACC) and lower structural covariance between the ACC and the cerebellum were observed in the MDD group. Additionally, individuals with MDD had significantly lower whole-brain intrinsic functional connectivity in the medial prefrontal cortex (mPFC). This mPFC region showed altered connectivity to the ventral lateral PFC (vlPFC) and local circuitry in MDD. Global connectivity in the ACC was negatively correlated with reported depressive symptomatology. The mPFC-vlPFC connectivity was positively correlated with depressive symptoms. Finally, we observed increased structure-to-function correlation in the PFC/ACC in the MDD group. Although across all analysis methods and modalities alterations in the PFC/ACC were a common finding, each modality and method detected alterations in subregions belonging to distinct large-scale brain networks. These exploratory results support the hypothesis that MDD is a systems level disorder affecting multiple brain networks located in the PFC and provide new insights into the pathophysiology of this disorder.
Justen, Christoph; Herbert, Cornelia
2016-01-01
So far, neurophysiological studies have investigated implicit and explicit self-related processing particularly for self-related stimuli such as the own face or name. The present study extends previous research to the implicit processing of self-related movement sounds and explores their spatio-temporal dynamics. Event-related potentials (ERPs) were assessed while participants (N = 12 healthy subjects) listened passively to previously recorded self- and other-related finger snapping sounds, presented either as deviants or standards during an oddball paradigm. Passive listening to low (500 Hz) and high (1000 Hz) pure tones served as additional control. For self- vs. other-related finger snapping sounds, analysis of ERPs revealed significant differences in the time windows of the N2a/MMN and P3. An subsequent source localization analysis with standardized low-resolution brain electromagnetic tomography (sLORETA) revealed increased cortical activation in distinct motor areas such as the supplementary motor area (SMA) in the N2a/mismatch negativity (MMN) as well as the P3 time window during processing of self- and other-related finger snapping sounds. In contrast, brain regions associated with self-related processing [e.g., right anterior/posterior cingulate cortex (ACC/PPC)] as well as the right inferior parietal lobule (IPL) showed increased activation particularly during processing of self- vs. other-related finger snapping sounds in the time windows of the N2a/MMN (ACC/PCC) or the P3 (IPL). None of these brain regions showed enhanced activation while listening passively to low (500 Hz) and high (1000 Hz) pure tones. Taken together, the current results indicate (1) a specific role of motor regions such as SMA during auditory processing of movement-related information, regardless of whether this information is self- or other-related, (2) activation of neural sources such as the ACC/PCC and the IPL during implicit processing of self-related movement stimuli, and (3) their differential temporal activation during deviance (N2a/MMN – ACC/PCC) and target detection (P3 – IPL) of self- vs. other-related movement sounds. PMID:27777557
Disordered amorphous calcium carbonate from direct precipitation
Farhadi Khouzani, Masoud; Chevrier, Daniel M.; Güttlein, Patricia; ...
2015-06-01
Amorphous calcium carbonate (ACC) is known to play a prominent role in biomineralization. Different studies on the structure of biogenic ACCs have illustrated that they can have distinct short-range orders. However, the origin of so-called proto-structures in synthetic and additive-free ACCs is not well understood. In the current work, ACC has been synthesised in iso-propanolic media by direct precipitation from ionic precursors, and analysed utilising a range of different techniques. The data suggest that this additive-free type of ACC does not resemble clear proto-structural motifs relating to any crystalline polymorph. This can be explained by the undefined pH value inmore » iso-propanolic media, and the virtually instantaneous precipitation. Altogether, this work suggests that aqueous systems and pathways involving pre-nucleation clusters are required for the generation of clear proto-structural features in ACC. Experiments on the ACC-to-crystalline transformation in solution with and without ethanol highlight that polymorph selection is under kinetic control, while the presence of ethanol can control dissolution re-crystallisation pathways.« less
Effect of adaptive cruise control systems on mixed traffic flow near an on-ramp
NASA Astrophysics Data System (ADS)
Davis, L. C.
2007-06-01
Mixed traffic flow consisting of vehicles equipped with adaptive cruise control (ACC) and manually driven vehicles is analyzed using car-following simulations. Simulations of merging from an on-ramp onto a freeway reported in the literature have not thus far demonstrated a substantial positive impact of ACC. In this paper cooperative merging for ACC vehicles is proposed to improve throughput and increase distance traveled in a fixed time. In such a system an ACC vehicle senses not only the preceding vehicle in the same lane but also the vehicle immediately in front in the other lane. Prior to reaching the merge region, the ACC vehicle adjusts its velocity to ensure that a safe gap for merging is obtained. If on-ramp demand is moderate, cooperative merging produces significant improvement in throughput (20%) and increases up to 3.6 km in distance traveled in 600 s for 50% ACC mixed flow relative to the flow of all-manual vehicles. For large demand, it is shown that autonomous merging with cooperation in the flow of all ACC vehicles leads to throughput limited only by the downstream capacity, which is determined by speed limit and headway time.
Sexual attraction enhances glutamate transmission in mammalian anterior cingulate cortex
Wu, Long-Jun; Kim, Susan S; Li, Xiangyao; Zhang, Fuxing; Zhuo, Min
2009-01-01
Functional human brain imaging studies have indicated the essential role of cortical regions, such as the anterior cingulate cortex (ACC), in romantic love and sex. However, the neurobiological basis of how the ACC neurons are activated and engaged in sexual attraction remains unknown. Using transgenic mice in which the expression of green fluorescent protein (GFP) is controlled by the promoter of the activity-dependent gene c-fos, we found that ACC pyramidal neurons are activated by sexual attraction. The presynaptic glutamate release to the activated neurons is increased and pharmacological inhibition of neuronal activities in the ACC reduced the interest of male mice to female mice. Our results present direct evidence of the critical role of the ACC in sexual attraction, and long-term increases in glutamate mediated excitatory transmission may contribute to sexual attraction between male and female mice. PMID:19419552
Hosking, Jay G; Cocker, Paul J; Winstanley, Catharine A
2014-06-01
Personal success often requires the choice to expend greater effort for larger rewards, and deficits in such effortful decision making accompany a number of illnesses including depression, schizophrenia, and attention-deficit/hyperactivity disorder. Animal models have implicated brain regions such as the basolateral amygdala (BLA) and anterior cingulate cortex (ACC) in physical effort-based choice, but disentangling the unique contributions of these two regions has proven difficult, and effort demands in industrialized society are predominantly cognitive in nature. Here we utilize the rodent cognitive effort task (rCET), a modification of the five-choice serial reaction-time task, wherein animals can choose to expend greater visuospatial attention to obtain larger sucrose rewards. Temporary inactivation (via baclofen-muscimol) of BLA and ACC showed dissociable effects: BLA inactivation caused hard-working rats to 'slack off' and 'slacker' rats to work harder, whereas ACC inactivation caused all animals to reduce willingness to expend mental effort. Furthermore, BLA inactivation increased the time needed to make choices, whereas ACC inactivation increased motor impulsivity. These data illuminate unique contributions of BLA and ACC to effort-based decision making, and imply overlapping yet distinct circuitry for cognitive vs physical effort. Our understanding of effortful decision making may therefore require expanding our models beyond purely physical costs.
Chen, Qing-Xia; Li, Jun-Jing; Wang, Xiao-Xiao; Lin, Pei-Yang; Zhang, Jie; Song, Chuan-Gui; Shao, Zhi-Ming
2017-01-24
Adenoid cystic carcinoma of the breast (breast-ACC) is a rare and indolent tumor with a good prognosis despite its triple-negative status. However, we observed different outcomes in the present study. Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we enrolled a total of 89,937 eligible patients with an estimated 86 breast-ACC cases and 89,851 invasive ductal carcinoma (IDC) patients. In our study, breast-ACC among women presented with a higher proportion of triple-negative breast cancer (TNBC), which was more likely to feature well-differentiated tumors, rare regional lymph node involvement and greater application of breast-conserving surgery (BCS). Kaplan-Meier analysis revealed that patients with breast-ACC and breast-IDC patients had similar breast cancer-specific survival (BCSS) and overall survival (OS). Moreover, using the propensity score matching method, no significant difference in survival was observed in matched pairs of breast-ACC and breast-IDC patients. Additionally, BCSS and OS did not differ significantly between TNBC-ACC and TNBC-IDC after matching patients for age, tumor size, and nodal status. Further subgroup analysis of molecular subtype indicated improved survival in breast-ACC patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/Her2-) tumors compared to IDC patients with HR+/Her2- tumors. However, the survival of ACC-TNBC and IDC-TNBC patients was similar. In conclusion, ACCs have an indolent clinical course and result in similar outcomes compared to IDC. Understanding these clinical characteristics and outcomes will endow doctors with evidence to provide the same intensive treatment for ACC-TNBC as for IDC-TNBC and lead to more individualized and tailored therapies for breast-ACC patients.
Lucas-Neto, Lia; Reimão, Sofia; Oliveira, Edson; Rainha-Campos, Alexandre; Sousa, João; Nunes, Rita G; Gonçalves-Ferreira, António; Campos, Jorge G
2015-07-01
The human nucleus accumbens (Acc) has become a target for deep brain stimulation (DBS) in some neuropsychiatric disorders. Nonetheless, even with the most recent advances in neuroimaging it remains difficult to accurately delineate the Acc and closely related subcortical structures, by conventional MRI sequences. It is our purpose to perform a MRI study of the human Acc and to determine whether there are reliable anatomical landmarks that enable the precise location and identification of the nucleus and its core/shell division. For the Acc identification and delineation, based on anatomical landmarks, T1WI, T1IR and STIR 3T-MR images were acquired in 10 healthy volunteers. Additionally, 32-direction DTI was obtained for Acc segmentation. Seed masks for the Acc were generated with FreeSurfer and probabilistic tractography was performed using FSL. The probability of connectivity between the seed voxels and distinct brain areas was determined and subjected to k-means clustering analysis, defining 2 different regions. With conventional T1WI, the Acc borders are better defined through its surrounding anatomical structures. The DTI color-coded vector maps and IR sequences add further detail in the Acc identification and delineation. Additionally, using probabilistic tractography it is possible to segment the Acc into a core and shell division and establish its structural connectivity with different brain areas. Advanced MRI techniques allow in vivo delineation and segmentation of the human Acc and represent an additional guiding tool in the precise and safe target definition for DBS. © 2015 International Neuromodulation Society.
Evaluating the safety impact of adaptive cruise control in traffic oscillations on freeways.
Li, Ye; Li, Zhibin; Wang, Hao; Wang, Wei; Xing, Lu
2017-07-01
Adaptive cruise control (ACC) has been considered one of the critical components of automated driving. ACC adjusts vehicle speeds automatically by measuring the status of the ego-vehicle and leading vehicle. Current commercial ACCs are designed to be comfortable and convenient driving systems. Little attention is paid to the safety impacts of ACC, especially in traffic oscillations when crash risks are the highest. The primary objective of this study was to evaluate the impacts of ACC parameter settings on rear-end collisions on freeways. First, the occurrence of a rear-end collision in a stop-and-go wave was analyzed. A car-following model in an integrated ACC was developed for a simulation analysis. The time-to-collision based factors were calculated as surrogate safety measures of the collision risk. We also evaluated different market penetration rates considering that the application of ACC will be a gradual process. The results showed that the safety impacts of ACC were largely affected by the parameters. Smaller time delays and larger time gaps improved safety performance, but inappropriate parameter settings increased the collision risks and caused traffic disturbances. A higher reduction of the collision risk was achieved as the ACC vehicle penetration rate increased, especially in the initial stage with penetration rates of less than 30%. This study also showed that in the initial stage, the combination of ACC and a variable speed limit achieved better safety improvements on congested freeways than each single technique. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ichesco, Eric; Quintero, Andres; Clauw, Daniel J; Peltier, Scott; Sundgren, Pia M; Gerstner, Geoffrey E; Schmidt-Wilcke, Tobias
2012-03-01
Among the most common chronic pain conditions, yet poorly understood, are temporomandibular disorders (TMDs), with a prevalence estimate of 3-15% for Western populations. Although it is increasingly acknowledged that central nervous system mechanisms contribute to pain amplification and chronicity in TMDs, further research is needed to unravel neural correlates that might abet the development of chronic pain. The insular cortex (IC) and cingulate cortex (CC) are both critically involved in the experience of pain. The current study sought specifically to investigate IC-CC functional connectivity in TMD patients and healthy controls (HCs), both during resting state and during the application of a painful stimulus. Eight patients with TMD, and 8 age- and sex-matched HCs were enrolled in the present study. Functional magnetic resonance imaging data during resting state and during the performance of a pressure pain stimulus to the temple were acquired. Predefined seed regions were placed in the IC (anterior and posterior insular cortices) and the extracted signal was correlated with brain activity throughout the whole brain. Specifically, we were interested whether TMD patients and HCs would show differences in IC-CC connectivity, both during resting state and during the application of a painful stimulus to the face. As a main finding, functional connectivity analyses revealed an increased functional connectivity between the left anterior IC and pregenual anterior cingulate cortex (ACC) in TMD patients, during both resting state and applied pressure pain. Within the patient group, there was a negative correlation between the anterior IC-ACC connectivity and clinical pain intensity as measured by a visual analog scale. Since the pregenual region of the ACC is critically involved in antinociception, we hypothesize that an increase in anterior IC-ACC connectivity is indicative of an adaptation of the pain modulatory system early in the chronification process. © 2011 American Headache Society.
Expression, purification, and characterization of human acetyl-CoA carboxylase 2.
Kim, Ki Won; Yamane, Harvey; Zondlo, James; Busby, James; Wang, Minghan
2007-05-01
The full-length human acetyl-CoA carboxylase 1 (ACC1) was expressed and purified to homogeneity by two separate groups (Y.G. Gu, M. Weitzberg, R.F. Clark, X. Xu, Q. Li, T. Zhang, T.M. Hansen, G. Liu, Z. Xin, X. Wang, T. McNally, H. Camp, B.A. Beutel, H.I. Sham, Synthesis and structure-activity relationships of N-{3-[2-(4-alkoxyphenoxy)thiazol-5-yl]-1-methylprop-2-ynyl}carboxy derivatives as selective acetyl-CoA carboxylase 2 inhibitors, J. Med. Chem. 49 (2006) 3770-3773; D. Cheng, C.H. Chu, L. Chen, J.N. Feder, G.A. Mintier, Y. Wu, J.W. Cook, M.R. Harpel, G.A. Locke, Y. An, J.K. Tamura, Expression, purification, and characterization of human and rat acetyl coenzyme A carboxylase (ACC) isozymes, Protein Expr. Purif., in press). However, neither group was successful in expressing the full-length ACC2 due to issues of solubility and expression levels. The two versions of recombinant human ACC2 in these reports are either truncated (lacking 1-148 aa) or have the N-terminal 275 aa replaced with the corresponding ACC1 region (1-133 aa). Despite the fact that ACC activity was observed in both cases, these constructs are not ideal because the N-terminal region of ACC2 could be important for the correct folding of the catalytic domains. Here, we report the high level expression and purification of full-length human ACC2 that lacks only the N-terminal membrane attachment sequence (1-20 and 1-26 aa, respectively) in Trichoplusia ni cells. In addition, we developed a sensitive HPLC assay to analyze the kinetic parameters of the recombinant enzyme. The recombinant enzyme is a soluble protein and has a K(m) value of 2 microM for acetyl-CoA, almost 30-fold lower than that reported for the truncated human ACC2. Our recombinant enzyme also has a lower K(m) value for ATP (K(m)=52 microM). Although this difference could be ascribed to different assay conditions, our data suggest that the longer human ACC2 produced in our system may have higher affinities for the substrates and could be more similar to the native enzyme.
Lu, Jie; Yao, Yufeng; Jiang, Weihong; Jiao, Ruishen
2003-02-01
Acetyl CoA carboxylase (EC 6.4.1.2, ACC) catalyzes the ATP-dependent carboxylation of acetyl CoA to yield malonyl CoA, which is the first committed step in fatty acid synthesis. A pair of degenerate PCR primers were designed according to the conserved amino acid sequence of AccA from M. tuberculosis and S. coelicolor. The product of the PCR amplification, a DNA fragment of 250bp was used as a probe for screening the U32 genomic cosmid library and its gene, accA, coding the biotinylated protein subunit of acetyl CoA carboxylase, was successfully cloned from U32. The accA ORF encodes a 598-amino-acid protein with the calculated molecular mass of 63.7kD, with 70.1% of G + C content. A typical Streptomyces RBS sequence, AGGAGG, was found at the - 6 position upstream of the start codon GTG. Analysis of the deduced amino acid sequence showed the presence of biotin-binding site and putative ATP-bicarbonate interaction region, which suggested the U32 AccA may act as a biotin carboxylase as well as a biotin carrier protein. Gene accA was then cloned into the pET28 (b) vector and expressed solubly in E. coli BL21 (DE3) by 0.1 mmol/L IPTG induction. Western blot confirmed the covalent binding of biotin with AccA. Northern blot analyzed transcriptional regulation of accA by 5 different nitrogen sources.
Extradural Spinal Metastasis of Adenoid Cystic Carcinoma (ACC): A Case Report
Nair, Rajesh; Upadhyaya, Sunil; Nayal, Bhavna; Shetty, Arjun
2015-01-01
Adenoid cystic carcinoma (ACC) is a rare malignant tumour of the major salivary glands. It accounts for 10-15% of all salivary gland tumours and 1% of all head and neck tumours. Surgical resection followed by radiation is the choice of treatment for ACC. However, late loco-regional recurrence and metastasis is often seen emphasizing the importance of long-term follow-up. We report an unusual case of extradural metastasis of ACC in the dorsal spine. The primary submandibular gland tumour was resected 11 y back. A recurrence had been detected two years prior to the occurrence of spinal metastasis. Surgical decompression was done which was followed by palliative radiotherapy. Patient is symptomatically better, ambulant and on regular follow-up. PMID:25738073
Regulatory brain development: balancing emotion and cognition.
Perlman, Susan B; Pelphrey, Kevin A
2010-01-01
Emotion regulation is a critical aspect of children's social development, yet few studies have examined the brain mechanisms involved in its development. Theoretical accounts have conceptualized emotion regulation as relying on prefrontal control of limbic regions, specifying the anterior cingulate cortex (ACC) as a key brain region. Functional magnetic resonance imaging in 5- to 11-year-olds during emotion regulation and processing of emotionally expressive faces revealed that older children preferentially recruited the more dorsal “cognitive” areas of the ACC, while younger children preferentially engaged the more ventral “emotional” areas. Additionally, children with more fearful temperaments exhibited more ventral ACC activity while less fearful children exhibited increased activity in the dorsal ACC. These findings provide insight into a potential neurobiological mechanism underlying well-documented behavioral and cognitive changes from more emotional to more cognitive regulatory strategies with increasing age, as well as individual differences in this developmental process as a function of temperament. Our results hold important implications for our understanding of normal development and should also help to inform our understanding and management of emotional disorders. © 2010 Psychology Press
NASA Astrophysics Data System (ADS)
Mayewski, Paul Andrew
2016-04-01
The demonstration using Greenland ice cores that abrupt shifts in climate, Dansgaard-Oeschger (D-O) events, existed during the last glacial period has had a transformational impact on our understanding of climate change in the naturally forced world. The demonstration that D-O events are globally distributed and that they operated during previous glacial periods has led to extensive research into the relative hemispheric timing and causes of these events. The emergence of civilization during our current interglacial, the Holocene, has been attributed to the "relative climate quiescence" of this period relative to the massive, abrupt shifts in climate that characterized glacial periods in the form of D-O events. But, everything is relative and climate change is no exception. The demise of past civilizations, (eg., Mesopatamian, Mayan and Norse) is integrally tied to abrupt climate change (ACC) events operating at regional scales. Regionally to globally distributed ACC events have punctuated the Holocene and extreme events have always posed significant challenges to humans and ecosystems. Current warming of the Arctic, in terms of length of the summer season, is as abrupt and massive, albeit not as extensive, as the transition from the last major D-O event, the Younger Dryas into the Holocene (Mayewski et al., 2013). Tropospheric source greenhouse gas rise and ozone depletion in the stratosphere over Antarctica are triggers for the modern advent of human emission instigated ACCs. Arctic warming and Antarctic ozone depletion have resulted in significance changes to the atmospheric circulation systems that transport heat, moisture, and pollutants in both hemispheres. Climate models offer a critical tool for assessing trends, but they cannot as yet predict ACC events, as evidenced by the inability of these models to predict the rapid onset of Arctic warming and resulting changes in atmospheric circulation; and in the model vs past analog differences in projections for the state of atmospheric circulation in the Southern Hemisphere that will result as a consequence of greenhouse gas rise and "healing" of the Antarctic ozone hole (Mayewski et al., 2015). Climate change perspective gained from instrumentally calibrated ice core and other past climate proxies is essential to the construction of plausible scenarios for future climate and actionable planning. More ACC events are in our future and the early manifestation of these events is apparent in the emerging change in the severity and frequency of extreme events. Searching for a precursor for ACC events is a major challenge for the scientific community and humanity. For the climate community to undertake this challenge it is necessary to investigate both past and present sub-seasonal and longer extreme events associated with past D-O and ACC events and their impact on societies. Examples of sub-seasonal scale investigation of these events will be included in the presentation. Mayewski, P.A., Sneed, S.B., Birkel, S.D., Kurbatov, A.V. and Maasch, Holocene warming marked by longer summers and reduced storm frequency around Greenland, Journal of Quaternary Science, 267-8179. DOl: I 0.1002/jqs.2684, 2013. Mayewski, P.A., Bertler, N., Birkel, S., Bracegirdle, T., Carleton, A., England, M., Goodwin, I., Kang, J-H., Mayewski, P., Russell, J., Schneider, S., Turner, J. and Vellicogna, I., 2015, Potential for Southern Hemisphere climate surprises, Journal of Quaternary Science (Rapid Communication) 30, 391-395, DOI: 10.1002/jqs.2794.
La Rosa, Stefano; Bernasconi, Barbara; Frattini, Milo; Tibiletti, Maria Grazia; Molinari, Francesca; Furlan, Daniela; Sahnane, Nora; Vanoli, Alessandro; Albarello, Luca; Zhang, Lizhi; Notohara, Kenji; Casnedi, Selenia; Chenard, Marie-Pierre; Adsay, Volkan; Asioli, Sofia; Capella, Carlo; Sessa, Fausto
2016-03-01
The molecular alterations of pancreatic acinar cell carcinomas (ACCs) are poorly understood and have been reported as being different from those in ductal adenocarcinomas. Loss of TP53 gene function in the pathogenesis of ACCs is controversial since contradictory findings have been published. A comprehensive analysis of the different possible genetic and epigenetic mechanisms leading to TP53 alteration in ACC has never been reported and hence the role of TP53 in the pathogenesis and/or progression of ACC remains unclear. We investigated TP53 alterations in 54 tumor samples from 44 patients, including primary and metastatic ACC, using sequencing analysis, methylation-specific multiplex ligation probe amplification, fluorescence in situ hybridization, and immunohistochemistry. TP53 mutations were found in 13 % of primary ACCs and in 31 % of metastases. Primary ACCs and metastases showed the same mutational profile, with the exception of one case, characterized by a wild-type sequence in the primary carcinoma and a mutation in the corresponding metastasis. FISH analysis revealed deletion of the TP53 region in 53 % of primary ACCs and in 50 % of metastases. Promoter hypermethylation was found in one case. The molecular alterations correlated well with the immunohistochemical findings. A statistically significant association was found between the combination of mutation of one allele and loss of the other allele of TP53 and worse survival.
Ronnebaum, Sarah M.; Joseph, Jamie W.; Ilkayeva, Olga; Burgess, Shawn C.; Lu, Danhong; Becker, Thomas C.; Sherry, A. Dean; Newgard, Christopher B.
2008-01-01
Acetyl-CoA carboxylase 1 (ACC1) currently is being investigated as a target for treatment of obesity-associated dyslipidemia and insulin resistance. To investigate the effects of ACC1 inhibition on insulin secretion, three small interfering RNA (siRNA) duplexes targeting ACC1 (siACC1) were transfected into the INS-1-derived cell line, 832/13; the most efficacious duplex was also cloned into an adenovirus and used to transduce isolated rat islets. Delivery of the siACC1 duplexes decreased ACC1 mRNA by 60–80% in 832/13 cells and islets and enzyme activity by 46% compared with cells treated with a non-targeted siRNA. Delivery of siACC1 decreased glucose-stimulated insulin secretion (GSIS) by 70% in 832/13 cells and by 33% in islets. Surprisingly, siACC1 treatment decreased glucose oxidation by 49%, and the ATP:ADP ratio by 52%, accompanied by clear decreases in pyruvate cycling activity and tricarboxylic acid cycle intermediates. Exposure of siACC1-treated cells to the pyruvate cycling substrate dimethylmalate restored GSIS to normal without recovery of the depressed ATP:ADP ratio. In siACC1-treated cells, glucokinase protein levels were decreased by 25%, which correlated with a 36% decrease in glycogen synthesis and a 33% decrease in glycolytic flux. Furthermore, acute addition of the ACC1 inhibitor 5-(tetradecyloxy)-2-furoic acid (TOFA) to β-cells suppressed [14C]glucose incorporation into lipids but had no effect on GSIS, whereas chronic TOFA administration suppressed GSIS and glucose metabolism. In sum, chronic, but not acute, suppression of ACC1 activity impairs GSIS via inhibition of glucose rather than lipid metabolism. These findings raise concerns about the use of ACC inhibitors for diabetes therapy. PMID:18381287
Ronnebaum, Sarah M; Joseph, Jamie W; Ilkayeva, Olga; Burgess, Shawn C; Lu, Danhong; Becker, Thomas C; Sherry, A Dean; Newgard, Christopher B
2008-05-23
Acetyl-CoA carboxylase 1 (ACC1) currently is being investigated as a target for treatment of obesity-associated dyslipidemia and insulin resistance. To investigate the effects of ACC1 inhibition on insulin secretion, three small interfering RNA (siRNA) duplexes targeting ACC1 (siACC1) were transfected into the INS-1-derived cell line, 832/13; the most efficacious duplex was also cloned into an adenovirus and used to transduce isolated rat islets. Delivery of the siACC1 duplexes decreased ACC1 mRNA by 60-80% in 832/13 cells and islets and enzyme activity by 46% compared with cells treated with a non-targeted siRNA. Delivery of siACC1 decreased glucose-stimulated insulin secretion (GSIS) by 70% in 832/13 cells and by 33% in islets. Surprisingly, siACC1 treatment decreased glucose oxidation by 49%, and the ATP:ADP ratio by 52%, accompanied by clear decreases in pyruvate cycling activity and tricarboxylic acid cycle intermediates. Exposure of siACC1-treated cells to the pyruvate cycling substrate dimethylmalate restored GSIS to normal without recovery of the depressed ATP:ADP ratio. In siACC1-treated cells, glucokinase protein levels were decreased by 25%, which correlated with a 36% decrease in glycogen synthesis and a 33% decrease in glycolytic flux. Furthermore, acute addition of the ACC1 inhibitor 5-(tetradecyloxy)-2-furoic acid (TOFA) to beta-cells suppressed [(14)C]glucose incorporation into lipids but had no effect on GSIS, whereas chronic TOFA administration suppressed GSIS and glucose metabolism. In sum, chronic, but not acute, suppression of ACC1 activity impairs GSIS via inhibition of glucose rather than lipid metabolism. These findings raise concerns about the use of ACC inhibitors for diabetes therapy.
Chun, Ji-Won; Park, Hae-Jeong; Kim, Dai Jin; Kim, Eosu; Kim, Jae-Jin
2017-07-01
Conflict processing mediated by fronto-striatal regions may be influenced by emotional properties of stimuli. This study aimed to examine the effects of emotion repetition on cognitive control in a conflict-provoking situation. Twenty-one healthy subjects were scanned using functional magnetic resonance imaging while performing a sequential cognitive conflict task composed of emotional stimuli. The regional effects were analyzed according to the repetition or non-repetition of cognitive congruency and emotional valence between the preceding and current trials. Post-incongruence interference in error rate and reaction time was significantly smaller than post-congruence interference, particularly under repeated positive and non-repeated positive, respectively, and post-incongruence interference, compared to post-congruence interference, increased activity in the ACC, DLPFC, and striatum. ACC and DLPFC activities were significantly correlated with error rate or reaction time in some conditions, and fronto-striatal connections were related to the conflict processing heightened by negative emotion. These findings suggest that the repetition of emotional stimuli adaptively regulates cognitive control and the fronto-striatal circuit may engage in the conflict adaptation process induced by emotion repetition. Both repetition enhancement and repetition suppression of prefrontal activity may underlie the relationship between emotion and conflict adaptation. Copyright © 2017 Elsevier B.V. All rights reserved.
Citrus diseases with global ramifications including citrus canker and huanglongbing
USDA-ARS?s Scientific Manuscript database
Although there are a number of diseases that plague citrus production worldwide, two bacterial diseases are particularly problematic. Both are of Asian origin and currently cause severe economic damage: Asiatic citrus canker (ACC) and citrus huanglongbing (HLB). Although ACC has been found in the ...
Acetyl-CoA carboxylase-a as a novel target for cancer therapy.
Wang, Chun; Rajput, Sandeep; Watabe, Kounosuke; Liao, Duan-Fang; Cao, Deliang
2010-01-01
Acetyl-CoA carboxylases (ACC) are rate-limiting enzymes in de novo fatty acid synthesis, catalyzing ATP-dependent carboxylation of acetyl-CoA to form malonyl-CoA. Malonyl-CoA is a critical bi-functional molecule, i.e., a substrate of fatty acid synthase (FAS) for acyl chain elongation (fatty acid synthesis) and an inhibitor of carnitine palmitoyltransferase I (CPT-I) for fatty acid beta-oxidation. Two ACC isoforms have been identified in mammals, i.e. ACC-alpha (ACCA, also termed ACC1) and ACC-beta (ACCB, also designated ACC2). ACC has long been used as a target for the management of metabolic diseases, such as obesity and metabolic syndrome, and various inhibitors have been developed in clinical trials. Recently, ACCA up-regulation has been recognized in multiple human cancers, promoting lipogenesis to meet the need of cancer cells for rapid growth and proliferation. Therefore, ACCA might be effective as a potent target for cancer intervention, and the inhibitors developed for the treatment of metabolic diseases would be potential therapeutic agents for cancer therapy. This review summarizes our recent findings and updates the current understanding of the ACCA with focus on cancer research.
NASA Astrophysics Data System (ADS)
Bout-Roumazeilles, V.; Beny, F.; Mazaud, A.; Michel, E.; Crosta, X.; Davies, G. R.; Bory, A. J. M.
2017-12-01
High-resolution sedimentological and geochemical records were obtained from two sediment cores recovered by the French R/V Marion Dufresne during the INDIEN-SUD-ACC cruises near the sub-Antarctic Kerguelen Islands (49°S). This area is ideal to record past oceanic and atmospheric changes in the Southern Ocean because they are currently located in the northern branch of the Antarctic Circumpolar Current and under the direct influence of Southern Hemisphere Westerly wind belt. This study focuses on the last termination, with specific emphasis on the impact of severe climatic events (Heinrich Stadial 1, Antarctic Cold Reversal, Younger Dryas) onto the ocean-atmospheric exchange. Results indicates that most of the sediment is derived from the Kerguelen Plateau, characterized by high smectite content. Periodically, a minor contribution of Antarctica is noticeable. In particular, illite variations suggest fast and short northward incursions of Antarctic Bottom Water, probably formed in the Prydz Bay during the last glaciation. Grainsize repartition combined to magnetic parameters show a southward migration of the ACC and the fronts associated from the beginning of the deglaciation, which is consistent with Southern Hemisphere climate variations. On the opposite, it highlights an asynchronous decrease of the ACC strength, with a large drop during the Antarctic Cold Reversal when atmospheric CO2 increase was slowed down. Thus, at least in the studied area, the ACC strength and the Antarctic Climate were not synchronous during the last deglaciation.
Mitchell, Rachel L C
2010-05-01
Selective attention is popularly assessed with colour Stroop tasks in which participants name the ink colour of colour words, whilst resisting interference from the natural tendency to read the words. Prior studies hinted that the key brain regions (dorsolateral prefrontal (dlPFC) and anterior cingulate cortex (ACC)) may vary their degree of involvement, dependent on attentional demand. This study aimed to determine whether a parametrically varied increase in attentional demand resulted in linearly increased activity in these regions, and/or whether additional regions would be recruited during high attentional demand. Twenty-eight healthy young adults underwent fMRI whilst naming the font colour of colour words. Linear increases in BOLD response were assessed with increasing percentage incongruent trials per block (0, 20, 40, 60, 80, and 100%). Whilst ACC activation increased linearly according to incongruity level, dlPFC activity appeared constant. Together with behavioural evidence of reduced Stroop interference, these data support a load-dependent conflict-related response in ACC, but not dlPFC.
Damiano, Fabrizio; Testini, Mariangela; Tocci, Romina; Gnoni, Gabriele V; Siculella, Luisa
2018-04-01
Acetyl-CoA carboxylase 1 (ACC1) is a cytosolic enzyme catalyzing the rate limiting step in de novo fatty acid biosynthesis. There is mounting evidence showing that ACC1 is susceptible to dysregulation and that it is over-expressed in liver diseases associated with lipid accumulation and in several cancers. In the present study, ACC1 regulation at the translational level is reported. Using several experimental approaches, the presence of an internal ribosome entry site (IRES) has been established in the 5' untranslated region (5' UTR) of the ACC1 mRNA. Transfection experiments with the ACC1 5' UTR inserted in a dicistronic reporter vector show a remarkable increase in the downstream cistron translation, through a cap-independent mechanism. The endoplasmic reticulum (ER) stress condition and the related unfolded protein response (UPR), triggered by treatment with thapsigargin and tunicamycin, cause an increase of the cap-independent translation of ACC1 mRNA in HepG2 cells, despite the overall reduction in global protein synthesis. Other stress conditions, such as serum starvation and incubation with hypoxia mimetic agent CoCl 2 , up-regulate ACC1 expression in HepG2 cells at the translational level. Overall, these findings indicate that the presence of an IRES in the ACC1 5' UTR allows ACC1 mRNA translation in conditions that are inhibitory to cap-dependent translation. A potential involvement of the cap-independent translation of ACC1 in several pathologies, such as obesity and cancer, has been discussed. Copyright © 2018 Elsevier B.V. All rights reserved.
Kaczkurkin, Antonia N.; Moore, Tyler M.; Calkins, Monica E.; Ciric, Rastko; Detre, John A.; Elliott, Mark A.; Foa, Edna B.; de La Garza, Angel Garcia; Roalf, David R.; Rosen, Adon; Ruparel, Kosha; Shinohara, Russell T.; Xia, Cedric H.; Wolf, Daniel H.; Gur, Raquel E.; Gur, Ruben C.; Satterthwaite, Theodore D.
2017-01-01
The high comorbidity among neuropsychiatric disorders suggests a possible common neurobiological phenotype. Resting-state regional cerebral blood flow (CBF) can be measured noninvasively with MRI and abnormalities in regional CBF are present in many neuropsychiatric disorders. Regional CBF may also provide a useful biological marker across different types of psychopathology. To investigate CBF changes common across psychiatric disorders, we capitalized upon a sample of 1,042 youths (ages 11 to 23 years) who completed cross-sectional imaging as part of the Philadelphia Neurodevelopmental Cohort. CBF during a resting state was quantified on a voxelwise basis using arterial spin labeled perfusion MRI at 3T. A dimensional measure of psychopathology was constructed using a bifactor model of item-level data from a psychiatric screening interview, which delineated four factors (fear, anxious-misery, psychosis, and behavioral symptoms) plus a general factor: overall psychopathology. Overall psychopathology was associated with elevated perfusion in several regions including the right dorsal anterior cingulate cortex (ACC) and left rostral ACC. Furthermore, several clusters were associated with specific dimensions of psychopathology. Psychosis symptoms were related to reduced perfusion in the left frontal operculum and insula, whereas fear symptoms were associated with less perfusion in the right occipital/fusiform gyrus and left subgenual ACC. Follow-up functional connectivity analyses using resting-state fMRI collected in the same participants revealed that overall psychopathology was associated with decreased connectivity between the dorsal ACC and bilateral caudate. Together, the results of this study demonstrate common and dissociable CBF abnormalities across neuropsychiatric disorders in youth. PMID:28924181
Phase transitions in biogenic amorphous calcium carbonate.
Gong, Yutao U T; Killian, Christopher E; Olson, Ian C; Appathurai, Narayana P; Amasino, Audra L; Martin, Michael C; Holt, Liam J; Wilt, Fred H; Gilbert, P U P A
2012-04-17
Crystalline biominerals do not resemble faceted crystals. Current explanations for this property involve formation via amorphous phases. Using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), here we examine forming spicules in embryos of Strongylocentrotus purpuratus sea urchins, and observe a sequence of three mineral phases: hydrated amorphous calcium carbonate (ACC · H(2)O) → dehydrated amorphous calcium carbonate (ACC) → calcite. Unexpectedly, we find ACC · H(2)O-rich nanoparticles that persist after the surrounding mineral has dehydrated and crystallized. Protein matrix components occluded within the mineral must inhibit ACC · H(2)O dehydration. We devised an in vitro, also using XANES-PEEM, assay to identify spicule proteins that may play a role in stabilizing various mineral phases, and found that the most abundant occluded matrix protein in the sea urchin spicules, SM50, stabilizes ACC · H(2)O in vitro.
Konsolaki, Eleni; Skaliora, Irini
2015-08-01
The mechanisms by which aging leads to alterations in brain structure and cognitive deficits are unclear. Α deficient cholinergic system has been implicated as one of the main factors that could confer a heightened vulnerability to the aging process, and mice lacking high-affinity nicotinic receptors (β2(-/-)) have been proposed as an animal model of accelerated cognitive aging. To date, however, age-related changes in neuronal microanatomy have not been studied in these mice. In the present study, we examine the neuronal structure of yellow fluorescent protein (YFP(+)) layer V neurons in 2 cytoarchitectonically distinct cortical regions in wild-type (WT) and β2(-/-) animals. We find that (1) substantial morphological differences exist between YFP(+) cells of the anterior cingulate cortex (ACC) and primary visual cortex (V1), in both genotypes; (2) in WT animals, ACC cells are more susceptible to aging compared with cells in V1; and (3) β2 deletion is associated with a regionally and temporally specific increase in vulnerability to aging. ACC cells exhibit a prematurely aged phenotype already at 4-6 months, whereas V1 cells are spared in adulthood but strongly affected in old animals. Collectively, our data reveal region-specific synergistic effects of aging and genotype and suggest distinct vulnerabilities in V1 and ACC neurons. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Li, Guilin; Wang, Lijun; Wang, Ying; Li, Han; Liu, Zhenguo; Wang, Hongfang; Xu, Baohua; Guo, Xingqi
2018-06-22
Y-box binding protein 1 (YB-1) is a member of the cold shock domain protein superfamily and is involved in development, environmental stresses and DNA oxidative damage in many organisms. However, the precise functions of YB-1 are still not well understood in various insects, including bees. In the current study, we identified a YB-1 gene in Apis cerana cerana (AccYB-1). The predicted cis-acting elements in the promoter sequence of AccYB-1 indicated its possible roles in development and stress responses. AccYB-1 expression was higher in one-day-old larvae and dark-eyed pupae than in other development stages. Tissue-specific expression analysis showed that the mRNA level of AccYB-1 was higher in the thorax and midgut than in other tissues. The results from real-time PCR showed that AccYB-1 was induced by many environmental stresses. Silencing AccYB-1 downregulated the transcriptional level of some growth- and development-related genes and antioxidant genes and decreased the enzyme activities of several antioxidant-related enzymes, further indicating a possible function of AccYB-1 in growth, development and stress responses. Taken together, our findings suggest that AccYB-1 may play an indispensable role in growth and development and environmental stress responses in Apis cerana cerana. To our knowledge, this is the first paper to explore the role of YB-1 in bees. Copyright © 2018. Published by Elsevier B.V.
van den Berg, M Johanneke; Bhatt, Deepak L; Kappelle, L Jaap; de Borst, Gert J; Cramer, Maarten J; van der Graaf, Yolanda; Steg, Ph Gabriel; Visseren, Frank L J
2017-11-14
To validate and assess performance of the current ACC/AHA very high risk criteria in patients with clinically manifest arterial disease. Data were used from the SMART study (n = 7216) and REACH Registry (n = 48 322), two prospective cohorts of patients with manifest atherosclerotic arterial disease. Prevalence and incidence rates of recurrent major adverse cardiovascular events (MACE) were calculated, according to the ACC/AHA VHR criteria (cardiovascular disease combined with diabetes, smoking, dyslipidaemia, and/or recent recurrent coronary events). Performance of the ACC/AHA criteria was compared with single very high risk factors in terms of C-statistics and Net Reclassification Index. All patients were at VHR according to the ESC guidelines (incidence of recurrent MACE in SMART was 2.4/100PY, with 95% CI 2.3-2.5/100PY and in REACH 5.1/100PY with 95% CI 5.0-5.3/100PY). In SMART 57% of the patients were at VHR according to the ACC/AHA criteria (incidence of recurrent MACE 2.7/100PY, 95% CI 2.5-2.9/100PY) and in REACH this was 64% (5.9/100PY, 95% CI 5.7-6.1/100PY). The C-statistic for the ACC/AHA VHR criteria was 0.53 in REACH and 0.54 in SMART. Very high risk factors with comparable or slightly better performance were eGFR < 45, polyvascular disease and age >70 years. Around two third of the patients meeting the ACC/AHA VHR criteria had a predicted 10-year risk of recurrent MACE <30%. The ACC/AHA VHR criteria have limited discriminative power. Identifying patients with clinically manifest arterial disease at VHR for recurrent vascular events using eGFR <45, polyvascular disease, or age >70 years performs as well as the ACC/AHA VHR criteria. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.
Wang, J; Cao, B; Yu, T R; Jelfs, B; Yan, J; Chan, R H M; Li, Y
2015-07-09
The rodent anterior cingulate cortex (ACC) is critical for visceral pain and pain-related aversive response in chronic visceral hypersensitive (VH) state. Long-term potentiation (LTP), induced by theta burst stimulation (TBS) in the medial thalamus (MT)-ACC pathway, is blocked in VH rats. However, the neuronal intrinsic firing characteristics and the MT-ACC connectivity have not been investigated in visceral pain. Using repetitive distension of the colon and rectum (rCRD) as a sensitization paradigm, we have identified that the spontaneous firing rates of ACC neurons and the CRD-stimulated neuronal firings were increased after repetitive visceral noxious stimulation. This correlates with increases in visceral pain responses (visceromotor responses, VMRs). Two multichannel arrays of electrodes were implanted in the MT and ACC. Recordings were performed in free-moving rats before and after repeated CRD treatment. Power spectral density analysis showed that the local field potential (LFP) recorded in the ACC displayed increases in theta band power (4-10 Hz) that were modulated by rCRD. Neural spike activity in the ACC becomes synchronized with ongoing theta oscillations of LFP. Furthermore, cross correlation analysis showed augmented synchronization of thalamo-ACC theta band LFPs, which was consistent with an increase of neuronal communication between the two regions. In conclusion, these results reveal theta oscillations and theta-frequency phase-locking as prominent features of neural activity in the ACC and a candidate neural mechanism underlying acute visceral pain. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Horn, Dorothea I.; Yu, Chunshui; Steiner, Johann; Buchmann, Julia; Kaufmann, Joern; Osoba, Annemarie; Eckert, Ulf; Zierhut, Kathrin C.; Schiltz, Kolja; He, Huiguang; Biswal, Bharat; Bogerts, Bernhard; Walter, Martin
2010-01-01
Glutamatergic mechanisms and resting-state functional connectivity alterations have been recently described as factors contributing to major depressive disorder (MDD). Furthermore, the pregenual anterior cingulate cortex (pgACC) seems to play an important role for major depressive symptoms such as anhedonia and impaired emotion processing. We investigated 22 MDD patients and 22 healthy subjects using a combined magnetic resonance spectroscopy (MRS) and resting-state functional magnetic resonance imaging (fMRI) approach. Severity of depression was rated using the 21-item Hamilton depression scale (HAMD) and patients were divided into severely and mildly depressed subgroups according to HAMD scores. Because of their hypothesized role in depression we investigated the functional connectivity between pgACC and left anterior insular cortex (AI). The sum of Glutamate and Glutamine (Glx) in the pgACC, but not in left AI, predicted the resting-state functional connectivity between the two regions exclusively in depressed patients. Furthermore, functional connectivity between these regions was significantly altered in the subgroup of severely depressed patients (HAMD > 15) compared to healthy subjects and mildly depressed patients. Similarly the Glx ratios, relative to Creatine, in the pgACC were lowest in severely depressed patients. These findings support the involvement of glutamatergic mechanisms in severe MDD which are related to the functional connectivity between pgACC and AI and depression severity. PMID:20700385
The influence of self-awareness on emotional memory formation: an fMRI study
Wing, Erik A.; Cabeza, Roberto
2016-01-01
Evidence from functional neuroimaging studies of emotional perception shows that when attention is focused on external features of emotional stimuli (external perceptual orienting—EPO), the amygdala is primarily engaged, but when attention is turned inwards towards one’s own emotional state (interoceptive self-orienting—ISO), regions of the salience network, such as the anterior insula (AI) and the dorsal anterior cingulate cortex (dACC), also play a major role. Yet, it is unknown if ISO boosts the contributions of AI and dACC not only to emotional ‘perception’ but also to emotional ‘memory’. To investigate this issue, participants were scanned with functional magnetic resonance imaging (fMRI) while viewing emotional and neutral pictures under ISO or EPO, and memory was tested several days later. The study yielded three main findings: (i) emotion boosted perception-related activity in the amygdala during both ISO and EPO and in the right AI exclusively during ISO; (ii) emotion augmented activity predicting subsequent memory in AI and dACC during ISO but not during EPO and (iii) high confidence memory was associated with increased amygdala–dACC connectivity, selectively for ISO encoding. These findings show, for the first time, that ISO promotes emotional memory formation via regions associated with interoceptive awareness of emotional experience, such as AI and dACC. PMID:26645274
The Family & Life Education Program.
ERIC Educational Resources Information Center
Brand, Mellie R.
The Family and Life Education program at Aims Community College (ACC) in Colorado began in 1967 as prenatal classes taught by volunteer instructors who were registered nurses with backgrounds in maternal-child health. Currently, the program, which is co-sponsored by ACC and North Colorado Medical Center, involves a program coordinator, three staff…
Roles and Responsibilities--Single College Orientation.
ERIC Educational Resources Information Center
Fonte, Richard
Austin Community College (ACC) is undergoing reorganization in an attempt to create a "single college" organizational structure to replace its current "campus with five competing colleges" model. By doing so, ACC hopes to create an atmosphere in which short and long range planning efforts are aimed at the overall good of the…
LING, SHIZHANG; RETTIG, ELENI M.; TAN, MARIETTA; CHANG, XIAOFEI; WANG, ZHIMING; BRAIT, MARIANA; BISHOP, JUSTIN A.; FERTIG, ELANA J.; CONSIDINE, MICHAEL; WICK, MICHAEL J.; HA, PATRICK K.
2016-01-01
Salivary gland adenoid cystic carcinoma (ACC) is a rare head and neck malignancy without molecular biomarkers that can be used to predict the chemotherapeutic response or prognosis of ACC. The regulation of gene expression of oncogenes and tumor suppressor genes (TSGs) through DNA promoter methylation may play a role in the carcinogenesis of ACC. To identify differentially methylated genes in ACC, a global demethylating agent, 5-aza-2′-deoxycytidine (5-AZA) was utilized to unmask putative TSG silencing in ACC xenograft models in mice. Fresh xenografts were passaged, implanted in triplicate in mice that were treated with 5-AZA daily for 28 days. These xenografts were then evaluated for genome-wide DNA methylation patterns using the Illumina Infinium HumanMethylation27 BeadChip array. Validation of the 32 candidate genes was performed by bisulfite sequencing (BS-seq) in a separate cohort of 6 ACC primary tumors and 6 normal control salivary gland tissues. Hypermethylation was identified in the HCN2 gene promoter in all 6 control tissues, but hypomethylation was found in all 6 ACC tumor tissues. Quantitative validation of HCN2 promoter methylation level in the region detected by BS-seq was performed in a larger cohort of primary tumors (n=32) confirming significant HCN2 hypomethylation in ACCs compared with normal samples (n=10; P=0.04). HCN2 immunohistochemical staining was performed on an ACC tissue microarray. HCN2 staining intensity and H-score, but not percentage of the positively stained cells, were significantly stronger in normal tissues than those of ACC tissues. With our novel screening and sequencing methods, we identified several gene candidates that were methylated. The most significant of these genes, HCN2, was actually hypomethylated in tumors. However, promoter methylation status does not appear to be a major determinant of HCN2 expression in normal and ACC tissues. HCN2 hypomethylation is a biomarker of ACC and may play an important role in the carcinogenesis of ACC. PMID:27212063
ACCE Study Tour to ISTE2011 (San Francisco, New York, Washington, Philadelphia)
ERIC Educational Resources Information Center
Gronn, Donna; Romeo, Geoff
2011-01-01
In June/July this year a group of 28 educators from across Australia travelled to the US on the 2011 ACCE ISTE Study Tour. The group comprised a very broad section of educators--primary, secondary and tertiary classroom teachers, ICT coordinators, managers, private consultants and regional office managers. The government, catholic and independent…
NASA Astrophysics Data System (ADS)
Liau, Jen-Ru; Chao, Benjamin F.
2017-07-01
The southern annular mode (SAM) in the atmosphere and the Antarctic circumpolar current (ACC) in the ocean play decisive roles in the climatic system of the mid- to high-latitude southern hemisphere. Using the time-variable gravity data from the GRACE satellite mission, we find the link between the space-time variabilities of the ACC and the SAM. We calculate the empirical orthogonal functions (EOF) of the non-seasonal ocean bottom pressure (OBP) field in the circum-Antarctic seas from the GRACE data for the period from 2003 to 2015. We find that the leading EOF mode of the non-seasonal OBP represents a unison OBP oscillation around Antarctica with time history closely in pace with that of the SAM Index with a high correlation of 0.77. This OBP variation gives rise to a variation in the geostrophic flow field; the result for the same EOF mode shows heightened variations in the zonal velocity that resides primarily in the eastern hemispheric portion of the ACC and coincided geographically with the southernmost boundary of the ACC's main stream. Confirming previous oceanographic studies, these geodetic satellite results provide independent information toward better understanding of the ACC-SAM process.
PROBING HUMAN AND MONKEY ANTERIOR CINGULATE CORTEX IN VARIABLE ENVIRONMENTS
Walton, Mark E.; Mars, Rogier B.
2008-01-01
Previous research has identified the anterior cingulate cortex (ACC) as an important node in the neural network underlying decision making in primates. Decision making can, however, be studied under large variety of circumstances, ranging from the standard well-controlled lab situation to more natural, stochastic settings during which multiple agents interact. Here, we illustrate how these different varieties of decision making studied can influence theories of ACC function in monkeys. Converging evidence from unit recordings and lesions studies now suggest that the ACC is important for interpreting outcome information according to the current task context to guide future action selection. We then apply this framework to the study of human ACC function and discuss its potential implications. PMID:18189014
Boorman, Erie D; Rushworth, Matthew F; Behrens, Tim E
2013-01-01
Although damage to medial frontal cortex causes profound decision-making impairments, it has been difficult to pinpoint the relative contributions of key anatomical subdivisions. Here we use fMRI to examine the contributions of human ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortex (dACC) during sequential choices between multiple alternatives – two key features of choices made in ecological settings. By carefully constructing options whose current value at any given decision was dissociable from their longer-term value, we were able to examine choices in current and long-term frames of reference. We present evidence showing that activity at choice and feedback in vmPFC and dACC was tied to the current choice and the best long-term option, respectively. vmPFC, mid-cingulate, and PCC encoded the relative value between the chosen and next-best option at each sequential decision, whereas dACC encoded the relative value of adapting choices from the option with the highest value in the longer-term. Furthermore, at feedback we identify temporally dissociable effects that predict repetition of the current choice and adaptation away from the long-term best option in vmPFC and dACC, respectively. These functional dissociations at choice and feedback suggest that sequential choices are subject to competing cortical mechanisms. PMID:23392656
Jayarajan, Rajan Nishanth; Agarwal, Sri Mahavir; Viswanath, Biju; Kalmady, Sunil V; Venkatasubramanian, Ganesan; Srinath, Shoba; Chandrashekar, C R; Janardhan Reddy, Y C
2015-01-01
Adult patients with Obsessive Compulsive Disorder (OCD) have been shown to have gray matter (GM) volume differences from healthy controls in multiple regions - the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), medial frontal gyri (MFG), striatum, thalamus, and superior parietal lobule. However, there is paucity of data with regard to juvenile OCD. Hence, we examined GM volume differences between juvenile OCD patients and matched healthy controls using voxel based morphometry (VBM) with the above apriori regions of interest. Fifteen right handed juvenile patients with OCD and age- sex- handedness- matched healthy controls were recruited after administering the Mini International Neuropsychiatric Interview-KID and the Children's Yale-Brown Obsessive Compulsive Scale, and scanned using a 3 Tesla magnetic resonance imaging scanner. VBM methodology was followed. In comparison with healthy controls, patients had significantly smaller GM volumes in left ACC. YBOCS total score (current) showed significant negative correlation with GM volumes in bilateral OFC, and left superior parietal lobule. These findings while reiterating the important role of the orbito-fronto-striatal circuitry, also implicate in the parietal lobe - especially the superior parietal lobule as an important structure involved in the pathogenesis of OCD.
Dong, J G; Kim, W T; Yip, W K; Thompson, G A; Li, L; Bennett, A B; Yang, S F
1991-08-01
1-Aminocyclopropane-1-carboxylate (ACC) synthase (EC 4.4.1.14) purified from apple (Malus sylvestris Mill.) fruit was subjected to trypsin digestion. Following separation by reversed-phase high-pressure liquid chromatography, ten tryptic peptides were sequenced. Based on the sequences of three tryptic peptides, three sets of mixed oligonucleotide probes were synthesized and used to screen a plasmid cDNA library prepared from poly(A)(+) RNA of ripe apple fruit. A 1.5-kb (kilobase) cDNA clone which hybridized to all three probes were isolated. The clone contained an open reading frame of 1214 base pairs (bp) encoding a sequence of 404 amino acids. While the polyadenine tail at the 3'-end was intact, it lacked a portion of sequence at the 5'-end. Using the RNA-based polymerase chain reaction, an additional sequence of 148 bp was obtained at the 5'-end. Thus, 1362 bp were sequenced and they encode 454 amino acids. The deduced amino-acid sequence contained peptide sequences corresponding to all ten tryptic fragments, confirming the identity of the cDNA clone. Comparison of the deduced amino-acid sequence between ACC synthase from apple fruit and those from tomato (Lycopersicon esculentum Mill.) and winter squash (Cucurbita maxima Duch.) fruits demonstrated the presence of seven highly conserved regions, including the previously identified region for the active site. The size of the translation product of ACC-synthase mRNA was similar to that of the mature protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), indicating that apple ACC-synthase undergoes only minor, if any, post-translational proteolytic processing. Analysis of ACC-synthase mRNA by in-vitro translation-immunoprecipitation, and by Northern blotting indicates that the ACC-synthase mRNA was undetectable in unripe fruit, but was accumulated massively during the ripening proccess. These data demonstrate that the expression of the ACC-synthase gene is developmentally regulated.
Gowland, Emily; Ball, Karen Le; Bryant, Catherine; Birns, Jonathan
2016-10-01
Acute care common stem acute medicine (ACCS AM) training was designed to develop competent multi-skilled acute physicians to manage patients with multimorbidity from 'door to discharge' in an era of increasing acute hospital admissions. Recent surveys by the Royal College of Physicians have suggested that acute medical specialties are proving less attractive to trainees. However, data on the career pathways taken by trainees completing core acute medical training has been lacking. Using London as a region with a 100% fill rate for its ACCS AM training programme, this study showed only 14% of trainees go on to higher specialty training in acute internal medicine and a further 10% to pursue higher medical specialty training with dual accreditation with internal medicine. 16% of trainees switched from ACCS AM to emergency medicine or anaesthetics during core ACCS training, and intensive care medicine proved to be the most popular career choice for ACCS AM trainees (21%). The ACCS AM training programme therefore does not appear to be providing what it was set out to do and this paper discusses the potential causes and effects. © Royal College of Physicians 2016. All rights reserved.
Ho, Tiffany C; Sacchet, Matthew D; Connolly, Colm G; Margulies, Daniel S; Tymofiyeva, Olga; Paulus, Martin P; Simmons, Alan N; Gotlib, Ian H; Yang, Tony T
2017-11-01
Recent evidence suggests that anterior cingulate cortex (ACC) maturation during adolescence contributes to or underlies the development of major depressive disorder (MDD) during this sensitive period. The ACC is a structure that sits at the intersection of several task-positive networks (eg, central executive network, CEN), which are still developing during adolescence. While recent work using seed-based approaches indicate that depressed adolescents show limited task-evoked vs resting-state connectivity (termed 'inflexibility') between the ACC and task-negative networks, no study has used network-based approaches to investigate inflexibility of the ACC in task-positive networks to understand adolescent MDD. Here, we used graph theory to compare flexibility of network-level topology in eight subregions of the ACC (spanning three task-positive networks) in 42 unmedicated adolescents with MDD and 53 well-matched healthy controls. All participants underwent fMRI scanning during resting state and a response inhibition task that robustly engages task-positive networks. Relative to controls, depressed adolescents were characterized by inflexibility in local efficiency of a key ACC node in the CEN: right dorsal anterior cingulate cortex/medial frontal gyrus (R dACC/MFG). Furthermore, individual differences in flexibility of local efficiency of R dACC/MFG significantly predicted inhibition performance, consistent with current literature demonstrating that flexible network organization affords successful cognitive control. Finally, reduced local efficiency of dACC/MFG during the task was significantly associated with an earlier age of depression onset, consistent with prior work suggesting that MDD may alter functional network development. Our results support a neurodevelopmental hypothesis of MDD wherein dysfunctional self-regulation is potentially reflected by altered ACC maturation.
NASA Astrophysics Data System (ADS)
Bischoff, Addi; Wurm, Gerhard; Chaussidon, Marc; Horstmann, Marian; Metzler, Knut; Weyrauch, Mona; Weinauer, Julia
2017-05-01
In Allende, a very complex compound chondrule (Allende compound chondrule; ACC) was found consisting of at least 16 subchondrules (14 siblings and 2 independents). Its overall texture can roughly be described as a barred olivine object (BO). The BO texture is similar in all siblings, but does not exist in the two independents, which appear as relatively compact olivine-rich units. Because of secondary alteration of pristine Allende components and the ACC in particular, only limited predictions can be made concerning the original compositions of the colliding melt droplets. Based on textural and mineralogical characteristics, the siblings must have been formed on a very short time scale in a dense, local environment. This is also supported by oxygen isotope systematics showing similar compositions for all 16 subchondrules. Furthermore, the ACC subchondrules are isotopically distinct from typical Allende chondrules, indicating formation in or reaction with a more 16O-poor reservoir. We modeled constraints on the particle density required at the ACC formation location, using textural, mineral-chemical, and isotopic observations on this multicompound chondrule to define melt droplet collision conditions. In this context, we discuss the possible relationship between the formation of complex chondrules and the formation of macrochondrules and cluster chondrites. While macrochondrules may have formed under similar or related conditions as complex chondrules, cluster chondrites certainly require different formation conditions. Cluster chondrites represent a mixture of viscously deformed, seemingly young chondrules of different chemical and textural types and a population of older chondrules. Concerning the formation of ACC calculations suggest the existence of very local, kilometer-sized, and super-dense chondrule-forming regions with extremely high solid-to-gas mass ratios of 1000 or more.
Digilio, M C; Giannotti, A; Floridia, G; Uccellatore, F; Mingarelli, R; Danesino, C; Dallapiccola, B; Zuffardi, O
1994-01-01
Two patients with trisomy 8 syndrome owing to an isodicentric 8p;8p chromosome are described. Case 1 had a 46,XX/46,XX,-8,+idic(8)(p23) karyotype while case 2, a male, had the same abnormal karyotype without evidence of mosaicism. In situ hybridisation, performed in case 1, showed that the isochromosome was asymmetrical. Agenesis of the corpus callosum (ACC), which is a feature of trisomy 8 syndrome, was found in both patients. Although ACC is associated with aneuploidies for different chromosomes, a review of published reports indicates that, when associated with chromosome 8, this defect is the result of duplication of a gene located within 8p21-pter. Molecular analysis in one of our patients led us to exclude the distal 23 Mb of 8p from this ACC region. Images PMID:8014974
GRACE Accelerometer data transplant
NASA Astrophysics Data System (ADS)
Bandikova, T.; McCullough, C. M.; Kruizinga, G. L. H.
2017-12-01
The Gravity Recovery and Climate Experiment (GRACE) has recently celebrated its 15th anniversary. The aging of the satellites brings along new challenges for both mission operation and science data delivery. Since September 2016, the accelerometer (ACC) onboard GRACE-B has been permanently turned off in order to reduce the battery load. The absence of the information about the non-gravitational forces acting on the spacecraft dramatically decreases the accuracy of the monthly gravity field solutions. The missing GRACE-B accelerometer data, however, can be recovered from the GRACE-A accelerometer measurement with satisfactory accuracy. In the current GRACE data processing, simple ACC data transplant is used which includes only attitude and time correction. The full ACC data transplant, however, requires not only the attitude and time correction, but also modeling of the residual accelerations due to thruster firings, which is the most challenging part. The residual linear accelerations ("thruster spikes") are caused by thruster imperfections such as misalignment of thruster pair, force imbalance or differences in reaction time. The thruster spikes are one of the most dominant high-frequency signals in the ACC measurement. The shape and amplitude of the thruster spikes are unique for each thruster pair, for each firing duration (30 ms - 1000 ms), for each x,y,z component of the ACC linear acceleration, and for each spacecraft. In our approach, the thruster spike model is an analytical function obtained by inverse Laplace transform of the ACC transfer function. The model shape parameters (amplitude, width and time delay) are estimated using Least squares method. The ACC data transplant is validated for days when ACC data from both satellites were available. The fully transplanted data fits the original GRACE-B measurement very well. The full ACC data transplant results in significantly reduced high frequency noise compared to the simple ACC transplant (i.e. without thruster spike modeling). The full ACC data transplant is a promising solution, which will allow GRACE to deliver high quality science data despite the serious problems related to satellite aging.
Alterations in conflict monitoring are related to functional connectivity in Parkinson's disease.
Rosenberg-Katz, Keren; Maidan, Inbal; Jacob, Yael; Giladi, Nir; Mirelman, Anat; Hausdorff, Jeffrey M
2016-09-01
Patients with Parkinson's disease (PD) have difficulties in executive functions including conflict monitoring. The neural mechanisms underlying these difficulties are not yet fully understood. In order to examine the neural mechanisms related to conflict monitoring in PD, we evaluated 35 patients with PD and 20 healthy older adults while they performed a word-color Stroop paradigm in the MRI. Specifically, we focused on changes between the groups in task-related functional connectivity using psycho-physiological interaction (PPI) analysis. The anterior cingulate cortex (ACC), which is a brain node previously associated with the Stroop paradigm, was selected as the seed region for this analysis. Patients with PD, as compared to healthy controls, had reduced task-related functional connectivity between the ACC and parietal regions including the precuneus and inferior parietal lobe. This was seen only in the incongruent Stroop condition. A higher level of connectivity between the ACC and precuneus was correlated with a lower error rate in the conflicting, incongruent Stroop condition in the healthy controls, but not in the patients with PD. Furthermore, the patients also had reduced functional connectivity between the ACC and the superior frontal gyrus which was present in both the incongruent and congruent task condition. The present findings shed light on brain mechanisms that are apparently associated with specific cognitive difficulties in patients with PD. Among patients with PD, impaired conflict monitoring processing within the ACC-based fronto-parietal network may contribute to difficulties under increased executive demands. Copyright © 2016 Elsevier Ltd. All rights reserved.
Adenoid Cystic Carcinoma of the Breast: A Clinical Case Report.
Kocaay, Akin Firat; Celik, Suleyman Utku; Hesimov, Ilkin; Eker, Tevfik; Percinel, Sibel; Demirer, Seher
2016-10-01
Adenoid cystic carcinoma (ACC) is an uncommon tumor of the breast, accounting for approximately 0.1% to 1% of all breast cancers. It is characterized by rare lymph node involvement and distant metastasis, and associated with a favorable prognosis with excellent survival, despite its triple-negative status. In the current state of knowledge, results of breast-conserving treatment with postoperative radiotherapy seem to be equivalent to mastectomy alone, with respect to survival for ACC of the breast. Due to its rarity, there is no consensus on optimal treatment for patients with ACC. Otherwise, the role of chemotherapy and hormonal therapy remains controversial. Further clinical studies are required to compare treatment options for ACC. But, a long-term follow-up is very important and mandatory for affected patients, due to the late onset of local relapse and occurrence of distant metastasis. Here, we report the case of a patient who presented with a palpable breast mass in the left breast that turned out to be an ACC of the breast.
Frontal Hyperconnectivity Related to Discounting and Reversal Learning in Cocaine Subjects
Camchong, Jazmin; MacDonald, Angus W; Nelson, Brent; Bell, Christopher; Mueller, Bryon A; Specker, Sheila; Lim, Kelvin O
2011-01-01
BACKGROUND Functional neuroimaging studies suggest that chronic cocaine use is associated with frontal lobe abnormalities. Functional connectivity (FC) alterations of cocaine dependent individuals (CD), however, are not yet clear. This is the first study to our knowledge that examines resting FC of anterior cingulate cortex (ACC) in CD. Because ACC is known to integrate inputs from different brain regions to regulate behavior, we hypothesize that CD will have connectivity abnormalities in ACC networks. In addition, we hypothesized that abnormalities would be associated with poor performance in delayed discounting and reversal learning tasks. METHODS Resting functional magnetic resonance imaging data were collected to look for FC differences between twenty-seven cocaine dependent individuals (CD) (5 females, age: M=39.73, SD=6.14) and twenty-four controls (5 females, age: M=39.76, SD = 7.09). Participants were assessed with delayed discounting and reversal learning tasks. Using seed-based FC measures, we examined FC in CD and controls within five ACC connectivity networks with seeds in subgenual, caudal, dorsal, rostral, and perigenual ACC. RESULTS CD showed increased FC within the perigenual ACC network in left middle frontal gyrus, ACC and middle temporal gyrus when compared to controls. FC abnormalities were significantly positively correlated with task performance in delayed discounting and reversal learning tasks in CD. CONCLUSIONS The present study shows that participants with chronic cocaine-dependency have hyperconnectivity within an ACC network known to be involved in social processing and mentalizing. In addition, FC abnormalities found in CD were associated with difficulties with delay rewards and slower adaptive learning. PMID:21371689
Couceiro, R; Carvalho, P; Paiva, R P; Henriques, J; Muehlsteff, J
2014-12-01
The presence of motion artifacts in photoplethysmographic (PPG) signals is one of the major obstacles in the extraction of reliable cardiovascular parameters in continuous monitoring applications. In the current paper we present an algorithm for motion artifact detection based on the analysis of the variations in the time and the period domain characteristics of the PPG signal. The extracted features are ranked using a normalized mutual information feature selection algorithm and the best features are used in a support vector machine classification model to distinguish between clean and corrupted sections of the PPG signal. The proposed method has been tested in healthy and cardiovascular diseased volunteers, considering 11 different motion artifact sources. The results achieved by the current algorithm (sensitivity--SE: 84.3%, specificity--SP: 91.5% and accuracy--ACC: 88.5%) show that the current methodology is able to identify both corrupted and clean PPG sections with high accuracy in both healthy (ACC: 87.5%) and cardiovascular diseases (ACC: 89.5%) context.
Paolini, Brielle M; Laurienti, Paul J; Simpson, Sean L; Burdette, Jonathan H; Lyday, Robert G; Rejeski, W Jack
2015-01-01
Obesity is a public health crisis in North America. While lifestyle interventions for weight loss (WL) remain popular, the rate of success is highly variable. Clearly, self-regulation of eating behavior is a challenge and patterns of activity across the brain may be an important determinant of success. The current study prospectively examined whether integration across the Hot-State Brain Network of Appetite (HBN-A) predicts WL after 6-months of treatment in older adults. Our metric for network integration was global efficiency (GE). The present work is a sub-study (n = 56) of an ongoing randomized clinical trial involving WL. Imaging involved a baseline food-cue visualization functional MRI (fMRI) scan following an overnight fast. Using graph theory to build functional brain networks, we demonstrated that regions of the HBN-A (insula, anterior cingulate cortex (ACC), superior temporal pole (STP), amygdala and the parahippocampal gyrus) were highly integrated as evidenced by the results of a principal component analysis (PCA). After accounting for known correlates of WL (baseline weight, age, sex, and self-regulatory efficacy) and treatment condition, which together contributed 36.9% of the variance in WL, greater GE in the HBN-A was associated with an additional 19% of the variance. The ACC of the HBN-A was the primary driver of this effect, accounting for 14.5% of the variance in WL when entered in a stepwise regression following the covariates, p = 0.0001. The HBN-A is comprised of limbic regions important in the processing of emotions and visceral sensations and the ACC is key for translating such processing into behavioral consequences. The improved integration of these regions may enhance awareness of body and emotional states leading to more successful self-regulation and to greater WL. This is the first study among older adults to prospectively demonstrate that, following an overnight fast, GE of the HBN-A during a food visualization task is predictive of WL.
Murphy, E.J; Watkins, J.L; Trathan, P.N; Reid, K; Meredith, M.P; Thorpe, S.E; Johnston, N.M; Clarke, A; Tarling, G.A; Collins, M.A; Forcada, J; Shreeve, R.S; Atkinson, A; Korb, R; Whitehouse, M.J; Ward, P; Rodhouse, P.G; Enderlein, P; Hirst, A.G; Martin, A.R; Hill, S.L; Staniland, I.J; Pond, D.W; Briggs, D.R; Cunningham, N.J; Fleming, A.H
2006-01-01
The Scotia Sea ecosystem is a major component of the circumpolar Southern Ocean system, where productivity and predator demand for prey are high. The eastward-flowing Antarctic Circumpolar Current (ACC) and waters from the Weddell–Scotia Confluence dominate the physics of the Scotia Sea, leading to a strong advective flow, intense eddy activity and mixing. There is also strong seasonality, manifest by the changing irradiance and sea ice cover, which leads to shorter summers in the south. Summer phytoplankton blooms, which at times can cover an area of more than 0.5 million km2, probably result from the mixing of micronutrients into surface waters through the flow of the ACC over the Scotia Arc. This production is consumed by a range of species including Antarctic krill, which are the major prey item of large seabird and marine mammal populations. The flow of the ACC is steered north by the Scotia Arc, pushing polar water to lower latitudes, carrying with it krill during spring and summer, which subsidize food webs around South Georgia and the northern Scotia Arc. There is also marked interannual variability in winter sea ice distribution and sea surface temperatures that is linked to southern hemisphere-scale climate processes such as the El Niño–Southern Oscillation. This variation affects regional primary and secondary production and influences biogeochemical cycles. It also affects krill population dynamics and dispersal, which in turn impacts higher trophic level predator foraging, breeding performance and population dynamics. The ecosystem has also been highly perturbed as a result of harvesting over the last two centuries and significant ecological changes have also occurred in response to rapid regional warming during the second half of the twentieth century. This combination of historical perturbation and rapid regional change highlights that the Scotia Sea ecosystem is likely to show significant change over the next two to three decades, which may result in major ecological shifts. PMID:17405210
Relation of obesity to neural activation in response to food commercials
Yokum, Sonja; Stice, Eric; Harris, Jennifer L.; Brownell, Kelly D.
2014-01-01
Adolescents view thousands of food commercials annually, but the neural response to food advertising and its association with obesity is largely unknown. This study is the first to examine how neural response to food commercials differs from other stimuli (e.g. non-food commercials and television show) and to explore how this response may differ by weight status. The blood oxygen level-dependent functional magnetic resonance imaging activation was measured in 30 adolescents ranging from lean to obese in response to food and non-food commercials imbedded in a television show. Adolescents exhibited greater activation in regions implicated in visual processing (e.g. occipital gyrus), attention (e.g. parietal lobes), cognition (e.g. temporal gyrus and posterior cerebellar lobe), movement (e.g. anterior cerebellar cortex), somatosensory response (e.g. postcentral gyrus) and reward [e.g. orbitofrontal cortex and anterior cingulate cortex (ACC)] during food commercials. Obese participants exhibited less activation during food relative to non-food commercials in neural regions implicated in visual processing (e.g. cuneus), attention (e.g. posterior cerebellar lobe), reward (e.g. ventromedial prefrontal cortex and ACC) and salience detection (e.g. precuneus). Obese participants did exhibit greater activation in a region implicated in semantic control (e.g. medial temporal gyrus). These findings may inform current policy debates regarding the impact of food advertising to minors. PMID:23576811
Zhang, Bin; Tian, Derun; Yu, Chunshui; Li, Meng; Zang, Yufeng; Liu, Yijun; Walter, Martin
2015-01-01
Obesity as a chronic disease is a major factor for insulin resistance and Type 2 diabetes, which has become a global health problem. In the present study, we used resting state functional MRI to investigate the amplitude of low frequency fluctuations of spontaneous signal during both hunger and satiety states in 20 lean and 20 obese males. We found that, before food intake, obese men had significantly greater baseline activity in the precuneus and lesser activity in dorsal anterior cingulate cortex (dACC) relative to lean subjects. Furthermore, after food intake, obese males had significantly lesser activity in dACC than lean males. We further found a significant positive correlation between precuneus activation and hunger ratings before food intake, while dACC activity was negatively correlated with plasma insulin levels before and after food intake. These results indicated that both precuneus and dACC may play an important role in eating behavior. While precuneus rather seemed to mediate subjective satiety, dACC levels rather reflected indirect measures of glucose utilization. PMID:26099208
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schlagnhaufer, C.D.; Arteca, R.N.; Pell, E.J.
When potato plants (Solanum tuberosum L. cv Norland) are subjected to oxone stress ethylene is emitted. Increases in ethylene production are often the result of increased expression of the enzyme ACC synthase. We used the polymerase chain reaction (PCR) to clone a cDNA encoding an ozone-induced ACC synthase. After treating potato plants with 300 ppb ozone for 4 h, RNA was extracted using a guanidinium isothiocyanate method. Using degenerate oligonucleotides corresponding to several conserved regions of ACC synthase sequences reported from different plant tissues as primers, we were able to reverse transcribe the RNA and amplify a cDNA for ACCmore » synthase. The clone is 1098 bp in length encoding for 386 amino acids comprising [approximately]80% of the protein. Computer analysis of the deduced amino acid sequence showed that our clone is 50-70% homologous with ACC synthase genes cloned from other plant tissues. Using the cDNA as a probe in northern analysis we found that there is little or no expression in control tissue: however there is a large increase in the expression of the ACC synthase message in response to ozone treatment.« less
Computational Models of Anterior Cingulate Cortex: At the Crossroads between Prediction and Effort.
Vassena, Eliana; Holroyd, Clay B; Alexander, William H
2017-01-01
In the last two decades the anterior cingulate cortex (ACC) has become one of the most investigated areas of the brain. Extensive neuroimaging evidence suggests countless functions for this region, ranging from conflict and error coding, to social cognition, pain and effortful control. In response to this burgeoning amount of data, a proliferation of computational models has tried to characterize the neurocognitive architecture of ACC. Early seminal models provided a computational explanation for a relatively circumscribed set of empirical findings, mainly accounting for EEG and fMRI evidence. More recent models have focused on ACC's contribution to effortful control. In parallel to these developments, several proposals attempted to explain within a single computational framework a wider variety of empirical findings that span different cognitive processes and experimental modalities. Here we critically evaluate these modeling attempts, highlighting the continued need to reconcile the array of disparate ACC observations within a coherent, unifying framework.
NASA Astrophysics Data System (ADS)
Peeken, Ilka
The development of phytoplankton biomass and composition was investigated on three occasions along a longitudinal transect (6°W) between 60°S and 47°S from October 13 to November 21, 1992 by measurement of photosynthetic pigments with high performance liquid chromatography (HPLC). Measured accessory pigment concentrations were multiplied by conversion factors to derive the proportions of phytoplankton groups contributing to the biomass indicator chlorophyll a. Phytoplankton blooms developed in the Polar Frontal region (PFr) and were dominated (80%) by diatoms. Other groups contributing to the phytoplankton included prymnesiophytes, green algae, autotrophic dinoflagellates, cryptophytes, pelagophytes and micromonadophytes, and their distributions varied with time. In contrast, phytoplankton biomass remained low in the southern Antarctic Circumpolar Current (ACC) and was dominated by flagellates, particularly green algae and prymnesiophytes. Green algae contributed more to total biomass than in previous investigations, partly attributed to "Chlorella-like" type organisms rather than prasinophytes. Cryptophytes decreased during the investigation, possibly due to salp grazing. No bloom was observed at the retreating ice-edge, presumably due to strong wind mixing. Only a slight increase in phytoplankton biomass, composed primarily of diatoms, was found at the ACC-Weddell Gyre front. Cluster analysis revealed that different phytoplankton communities characterised the different water masses of the PFr and southern ACC; the history of different water masses in the PFr could be reconstructed on this basis.
Amemori, Ken-ichi; Amemori, Satoko
2015-01-01
The judgment of whether to accept or to reject an offer is determined by positive and negative affect related to the offer, but affect also induces motivational responses. Rewarding and aversive cues influence the firing rates of many neurons in primate prefrontal and cingulate neocortical regions, but it still is unclear whether neurons in these regions are related to affective judgment or to motivation. To address this issue, we recorded simultaneously the neuronal spike activities of single units in the dorsolateral prefrontal cortex (dlPFC) and the anterior cingulate cortex (ACC) of macaque monkeys as they performed approach–avoidance (Ap–Av) and approach–approach (Ap–Ap) decision-making tasks that can behaviorally dissociate affective judgment and motivation. Notably, neurons having activity correlated with motivational condition could be distinguished from neurons having activity related to affective judgment, especially in the Ap–Av task. Although many neurons in both regions exhibited similar, selective patterns of task-related activity, we found a larger proportion of neurons activated in low motivational conditions in the dlPFC than in the ACC, and the onset of this activity was significantly earlier in the dlPFC than in the ACC. Furthermore, the temporal onsets of affective judgment represented by neuronal activities were significantly slower in the low motivational conditions than in the other conditions. These findings suggest that motivation and affective judgment both recruit dlPFC and ACC neurons but with differential degrees of involvement and timing. PMID:25653353
High intensity interval training improves liver and adipose tissue insulin sensitivity.
Marcinko, Katarina; Sikkema, Sarah R; Samaan, M Constantine; Kemp, Bruce E; Fullerton, Morgan D; Steinberg, Gregory R
2015-12-01
Endurance exercise training reduces insulin resistance, adipose tissue inflammation and non-alcoholic fatty liver disease (NAFLD), an effect often associated with modest weight loss. Recent studies have indicated that high-intensity interval training (HIIT) lowers blood glucose in individuals with type 2 diabetes independently of weight loss; however, the organs affected and mechanisms mediating the glucose lowering effects are not known. Intense exercise increases phosphorylation and inhibition of acetyl-CoA carboxylase (ACC) by AMP-activated protein kinase (AMPK) in muscle, adipose tissue and liver. AMPK and ACC are key enzymes regulating fatty acid metabolism, liver fat content, adipose tissue inflammation and insulin sensitivity but the importance of this pathway in regulating insulin sensitivity with HIIT is unknown. In the current study, the effects of 6 weeks of HIIT were examined using obese mice with serine-alanine knock-in mutations on the AMPK phosphorylation sites of ACC1 and ACC2 (AccDKI) or wild-type (WT) controls. HIIT lowered blood glucose and increased exercise capacity, food intake, basal activity levels, carbohydrate oxidation and liver and adipose tissue insulin sensitivity in HFD-fed WT and AccDKI mice. These changes occurred independently of weight loss or reductions in adiposity, inflammation and liver lipid content. These data indicate that HIIT lowers blood glucose levels by improving adipose and liver insulin sensitivity independently of changes in adiposity, adipose tissue inflammation, liver lipid content or AMPK phosphorylation of ACC.
Dorsal Anterior Cingulate Thickness Is Related to Alexithymia in Childhood Trauma-Related PTSD
Demers, Lauren A.; Olson, Elizabeth A.; Crowley, David J.; Rauch, Scott L.; Rosso, Isabelle M.
2015-01-01
Alexithymia, or “no words for feelings”, is highly prevalent in samples with childhood maltreatment and posttraumatic stress disorder (PTSD). The dorsal anterior cingulate cortex (dACC) has been identified as a key region involved in alexithymia, early life trauma, and PTSD. Functional alterations in the dACC also have been associated with alexithymia in PTSD. This study examined whether dACC morphology is a neural correlate of alexithymia in child maltreatment-related PTSD. Sixteen adults with PTSD and a history of childhood sexual abuse, physical abuse, or exposure to domestic violence, and 24 healthy controls (HC) completed the Toronto Alexithymia Scale 20 (TAS–20) and underwent magnetic resonance imaging. Cortical thickness of the dACC was measured using FreeSurfer, and values were correlated with TAS–20 scores, controlling for sex and age, in both groups. Average TAS–20 score was significantly higher in the PTSD than the HC group. TAS–20 scores were significantly positively associated with dACC thickness only in the PTSD group. This association was strongest in the left hemisphere and for TAS–20 subscales that assess difficulty identifying and describing feelings. We found that increasing dACC gray matter thickness is a neural correlate of greater alexithymia in the context of PTSD with childhood maltreatment. While findings are correlational, they motivate further inquiry into the relationships between childhood adversity, emotional awareness and expression, and dACC morphologic development in trauma-related psychopathology. PMID:26439117
Furlan, Daniela; Sahnane, Nora; Bernasconi, Barbara; Frattini, Milo; Tibiletti, Maria Grazia; Molinari, Francesca; Marando, Alessandro; Zhang, Lizhi; Vanoli, Alessandro; Casnedi, Selenia; Adsay, Volkan; Notohara, Kenji; Albarello, Luca; Asioli, Sofia; Sessa, Fausto; Capella, Carlo; La Rosa, Stefano
2014-05-01
Genetic and epigenetic alterations involved in the pathogenesis of pancreatic acinar cell carcinomas (ACCs) are poorly characterized, including the frequency and role of gene-specific hypermethylation, chromosome aberrations, and copy number alterations (CNAs). A subset of ACCs is known to show alterations in the APC/β-catenin pathway which includes mutations of APC gene. However, it is not known whether, in addition to mutation, loss of APC gene function can occur through alternative genetic and epigenetic mechanisms such as gene loss or promoter methylation. We investigated the global methylation profile of 34 tumor suppressor genes, CNAs of 52 chromosomal regions, and APC gene alterations (mutation, methylation, and loss) together with APC mRNA level in 45 ACCs and related peritumoral pancreatic tissues using methylation-specific multiplex ligation probe amplification (MS-MLPA), fluorescence in situ hybridization (FISH), mutation analysis, and reverse transcription-droplet digital PCR. ACCs did not show an extensive global gene hypermethylation profile. RASSF1 and APC were the only two genes frequently methylated. APC mutations were found in only 7 % of cases, while APC loss and methylation were more frequently observed (48 and 56 % of ACCs, respectively). APC mRNA low levels were found in 58 % of cases and correlated with CNAs. In conclusion, ACCs do not show extensive global gene hypermethylation. APC alterations are frequently involved in the pathogenesis of ACCs mainly through gene loss and promoter hypermethylation, along with reduction of APC mRNA levels.
Liu, Xiao-Yu; Liu, Zhi-Jian; He, Hong; Zhang, Chen; Wang, Yun-Long
2015-01-01
MicroRNAs (miRNAs) play critical roles in carcinogenesis and tumor progression. Recent research has revealed miR-101-3p as an important regulator in several cancers. Nevertheless, its function in salivary gland Adenoid cystic carcinoma (ACC), a relatively rare malignance with poor long-term survival rate arisen in head and neck region, remain unknown. In this study, down-regulated miR-101-3p expression was detected in ACC tissues and ACC cell lines with high potential for metastasis. Ectopic expression of miR-101-3p significantly repressed the invasion, proliferation, colony formation, and formation of nude mice xenografts and induced potent apoptosis in ACC cell lines. The provirus integration site for Moloney murine leukemia virus 1 (Pim-1) oncogene was subsequently confirmed as a direct target gene of miR-101-3p in ACC. Functional restoration assays revealed that miR-101-3p inhibits cell growth and invasion by directly decreasing Pim-1 expression. Protein levels of Survivin, Cyclin D1 and β-catenin were also down-regulated by miR-101-3p. miR-101-3p enhanced the sensitivity of cisplatin in ACC cell lines. Taken together, our results demonstrate that the novel miR-101-3p/Pim-1 axis provides excellent insights into the carcinogenesis and tumor progression of ACC and may be a promising therapeutic target for this type of cancer. PMID:26693056
Kühn, Simone; Gallinat, Jürgen
2011-04-01
The present quantitative meta-analysis set out to test whether cue-reactivity responses in humans differ across drugs of abuse and whether these responses constitute the biological basis of drug craving as a core psychopathology of addiction. By means of activation likelihood estimation, we investigated the concurrence of brain regions activated by cue-induced craving paradigms across studies on nicotine, alcohol and cocaine addicts. Furthermore, we analysed the concurrence of brain regions positively correlated with self-reported craving in nicotine and alcohol studies. We found direct overlap between nicotine, alcohol and cocaine cue reactivity in the ventral striatum. In addition, regions of close proximity were observed in the anterior cingulate cortex (ACC; nicotine and cocaine) and amygdala (alcohol, nicotine and cocaine). Brain regions of concurrence in drug cue-reactivity paradigms that overlapped with brain regions of concurrence in self-reported craving correlations were found in the ACC, ventral striatum and right pallidum (for alcohol). This first quantitative meta-analysis on drug cue reactivity identifies brain regions underlying nicotine, alcohol and cocaine dependency, i.e. the ventral striatum. The ACC, right pallidum and ventral striatum were related to drug cue reactivity as well as self-reported craving, suggesting that this set of brain regions constitutes the core circuit of drug craving in nicotine and alcohol addiction. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.
Gerretsen, Philip; Graff-Guerrero, Ariel; Menon, Mahesh; Pollock, Bruce G; Kapur, Shitij; Vasdev, Neil; Houle, Sylvain; Mamo, David
2010-01-01
Social behavior and desire for social relationships have been independently linked to the serotonergic system, the prefrontal cortex, especially the orbitofrontal cortex (OFC), and the anterior cingulate cortex (ACC). The goal of this study was to explore the role of serotonin 5HT(2A) receptors in these brain regions in forming and maintaining close interpersonal relationships. Twenty-four healthy subjects completed the Temperament and Character Inventory (TCI) prior to undergoing [(18)F]setoperone brain positron emission tomography (PET) to measure serotonin 5HT(2A) receptor availability within the OFC (BA 11 and 47) and ACC (BA 32). We explored the relationship between desire for social relationships, as measured by the TCI reward dependence (RD) scale, and 5HT(2A) receptor non-displaceable binding potential (BP(nd)) in these regions. Scores of RD were negatively correlated with 5HT(2A) BP(nd) in the ACC (BA 32, r = -.528, p = .012) and OFC (BA 11, r = -.489, p = .021; BA 47, r = -.501, p = .017). These correlations were corroborated by a voxel-wise analysis. These results suggest that the serotonergic system may have a regulatory effect on the OFC and ACC for establishing and maintaining social relationships.
Distracted and down: neural mechanisms of affective interference in subclinical depression
Andrews-Hanna, Jessica R.; Spielberg, Jeffrey M.; Warren, Stacie L.; Sutton, Bradley P.; Miller, Gregory A.; Heller, Wendy; Banich, Marie T.
2015-01-01
Previous studies have shown that depressed individuals have difficulty directing attention away from negative distractors, a phenomenon known as affective interference. However, findings are mixed regarding the neural mechanisms and network dynamics of affective interference. The present study addressed these issues by comparing neural activation during emotion-word and color-word Stroop tasks in participants with varying levels of (primarily subclinical) depression. Depressive symptoms predicted increased activation to negative distractors in areas of dorsal anterior cingulate cortex (dACC) and posterior cingulate cortex (PCC), regions implicated in cognitive control and internally directed attention, respectively. Increased dACC activity was also observed in the group-average response to incongruent distractors, suggesting that dACC activity during affective interference is related to overtaxed cognitive control. In contrast, regions of PCC were deactivated across the group in response to incongruent distractors, suggesting that PCC activity during affective interference represents task-independent processing. A psychophysiological interaction emerged in which higher depression predicted more positively correlated activity between dACC and PCC during affective interference, i.e. greater connectivity between cognitive control and internal-attention systems. These findings suggest that, when individuals high in depression are confronted by negative material, increased attention to internal thoughts and difficulty shifting resources to the external world interfere with goal-directed behavior. PMID:25062838
Panaccione, Alexander; Chang, Michael T.; Ivanov, Sergey V.
2016-01-01
Objectives This review surveys trialed therapies and molecular defects in adenoid cystic carcinoma (ACC), with an emphasis on neural crest‐like stemness characteristics of newly discovered cancer stem cells (CSCs) and therapies that may target these CSCs. Data Sources Articles available on Pubmed or OVID MEDLINE databases and unpublished data. Review Methods Systematic review of articles pertaining to ACC and neural crest‐like stem cells. Results Adenoid cystic carcinoma of the salivary gland is a slowly growing but relentless cancer that is prone to nerve invasion and metastases. A lack of understanding of molecular etiology and absence of targetable drivers has limited therapy for patients with ACC to surgery and radiation. Currently, no curative treatments are available for patients with metastatic disease, which highlights the need for effective new therapies. Research in this area has been inhibited by the lack of validated cell lines and a paucity of clinically useful markers. The ACC research environment has recently improved, thanks to the introduction of novel tools, technologies, approaches, and models. Improved understanding of ACC suggests that neural crest‐like stemness is a major target in this rare tumor. New cell culture techniques and patient‐derived xenografts provide tools for preclinical testing. Conclusion Preclinical research has not identified effective targets in ACC, as confirmed by the large number of failed clinical trials. New molecular data suggest that drivers of neural crest‐like stemness may be required for maintenance of ACC; as such, CSCs are a target for therapy of ACC. PMID:28894804
Partially dissociable roles of OFC and ACC in stimulus-guided and action-guided decision making.
Khani, Abbas
2014-05-01
Recently, the functional specialization of prefrontal areas of the brain, and, specifically, the functional dissociation of the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC), during decision making have become a particular focus of research. A number of neuropsychological and lesion studies have shown that the OFC and ACC have dissociable functions in various dimensions of decision making, which are supported by their different anatomical connections. A recent single-neuron study, however, described a more complex picture of the functional dissociation between these two frontal regions during decision making. Here, I discuss the results of that study and consider alternative interpretations in connection with other findings.
Frontal hyperconnectivity related to discounting and reversal learning in cocaine subjects.
Camchong, Jazmin; MacDonald, Angus W; Nelson, Brent; Bell, Christopher; Mueller, Bryon A; Specker, Sheila; Lim, Kelvin O
2011-06-01
Functional neuroimaging studies suggest that chronic cocaine use is associated with frontal lobe abnormalities. Functional connectivity (FC) alterations of cocaine-dependent individuals (CD), however, are not yet clear. This is the first study to our knowledge that examines resting FC of anterior cingulate cortex (ACC) in CD. Because ACC is known to integrate inputs from different brain regions to regulate behavior, we hypothesized that CD will have connectivity abnormalities in ACC networks. In addition, we hypothesized that abnormalities would be associated with poor performance in delayed discounting and reversal learning tasks. Resting functional magnetic resonance imaging data were collected to look for FC differences between 27 CD (5 women, age: M = 39.73, SD = 6.14 years) and 24 control subjects (5 women, age: M = 39.76, SD = 7.09 years). Participants were assessed with delayed discounting and reversal learning tasks. With seed-based FC measures, we examined FC in CD and control subjects within five ACC connectivity networks with seeds in subgenual, caudal, dorsal, rostral, and perigenual ACC. The CD showed increased FC within the perigenual ACC network in left middle frontal gyrus, ACC, and middle temporal gyrus when compared with control subjects. The FC abnormalities were significantly positively correlated with task performance in delayed discounting and reversal learning tasks in CD. The present study shows that participants with chronic cocaine-dependency have hyperconnectivity within an ACC network known to be involved in social processing and "mentalizing." In addition, FC abnormalities found in CD were associated with difficulties with delay rewards and slower adaptive learning. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Dedovic, Katarina; Slavich, George M.; Muscatell, Keely A.; Irwin, Michael R.; Eisenberger, Naomi I.
2016-01-01
The dorsal anterior cingulate cortex (dACC) is recruited when a person is socially rejected or negatively evaluated. However, it remains to be fully understood how this region responds to repeated exposure to personally-relevant social evaluation, in both healthy populations and those vulnerable to Major Depressive Disorder (MDD), as well as how responding in these regions is associated with subsequent clinical functioning. To address this gap in the literature, we recruited 17 young women with past history of MDD (previously depressed) and 31 healthy controls and exposed them to a social evaluative session in a neuroimaging environment. In two bouts, participants received an equal amount of positive, negative, and neutral feedback from a confederate. All participants reported increases in feelings of social evaluation in response to the evaluative task. However, compared to healthy controls, previously depressed participants tended to show greater increases in depressed mood following the task. At the neural level, in response to negative (vs. positive) feedback, no main effect of group or evaluation periods was observed. However, a significant interaction between group and evaluation periods was found. Specifically, over the two bouts of evaluation, activity in the dACC decreased among healthy participants while it increased among previously depressed individuals. Interestingly and unexpectedly, in the previously depressed group specifically, this increased activity in dACC over time was associated with lower levels of depressive symptoms at baseline and at 6-months following the evaluation session (controlling for baseline levels). Thus, the subset of previously depressed participants who showed increases in the recruitment of the dACC over time in response to the negative evaluation seemed to fair better emotionally. These findings suggest that examining how the dACC responds to repeated bouts of negative evaluation reveals a new dimension to the role of the dACC in processing exclusion and contributing to mental health outcomes in a population vulnerable to MDD. Further, investigation of the dynamics of the dACC response to negative social evaluation is warranted. PMID:27065828
The role of the anterior cingulate cortex in emotional response inhibition.
Albert, Jacobo; López-Martín, Sara; Tapia, Manuel; Montoya, Daniel; Carretié, Luis
2012-09-01
Although the involvement of the anterior cingulate cortex (ACC) in emotional response inhibition is well established, there are several outstanding issues about the nature of this involvement that are not well understood. The present study aimed to examine the precise contribution of the ACC to emotion-modulated response inhibition by capitalizing on fine temporal resolution of the event-related potentials (ERPs) and the recent advances in source localization. To this end, participants (N = 30) performed an indirect affective Go/Nogo task (i.e., unrelated to the emotional content of stimulation) that required the inhibition of a motor response to three types of visual stimuli: arousing negative (A-), neutral (N), and arousing positive (A+). Behavioral data revealed that participants made more commission errors to A+ than to N and A-. Electrophysiological data showed that a specific region of the ACC at the intersection of its dorsal and rostral subdivisions was significantly involved in the interaction between emotional processing and motor inhibition. Specifically, activity reflecting this interaction was observed in the P3 (but not in the N2) time range, and was greater during the inhibition of responses to A+ than to N and A-. Additionally, regression analyses showed that inhibition-related activity within this ACC region was associated with the emotional content of the stimuli (its activity increased as stimulus valence was more positive), and also with behavioral performance (both with reaction times and commission errors). The present results provide additional data for understanding how, when, and where emotion interacts with response inhibition within the ACC. Copyright © 2011 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin
2016-11-01
Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.
Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin
2016-11-21
Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds' Glx, Cho, Cr in the ACC and HCs' mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds' Glx and Cr in the PC and HCs' mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.
Role of right pregenual anterior cingulate cortex in self-conscious emotional reactivity
Sollberger, Marc; Seeley, William W.; Rankin, Katherine P.; Ascher, Elizabeth A.; Rosen, Howard J.; Miller, Bruce L.; Levenson, Robert W.
2013-01-01
Self-conscious emotions such as embarrassment arise when one’s actions fail to meet salient social expectations and are accompanied by marked physiological and behavioral activation. We investigated the neural correlates of self-conscious emotional reactivity in 27 patients with behavioral variant frontotemporal dementia (bvFTD), a neurodegenerative disease that disrupts self-conscious emotion and targets brain regions critical for emotional functioning early in the disease course, and in 33 healthy older controls. Subjects participated in an embarrassing karaoke task in which they watched a video clip of themselves singing. They also watched a sad film clip; these data were used to control for non-self-conscious emotional reactivity in response to audiovisual stimuli. Using Freesurfer to quantify regional brain volumes from structural magnetic resonance imaging, right pregenual anterior cingulate cortex (pACC) gray matter volume was the only brain region that was a significant predictor of self-conscious emotion. Smaller pACC volume was associated with attenuated physiological and behavioral self-conscious emotional reactivity, and this relationship was not specific to diagnosis. We argue that these results reflect the significant role that right pACC plays in the visceromotor responding that accompanies self-conscious emotion and that neurodegeneration in this region may underlie the self-conscious emotional decline seen in bvFTD. PMID:22345371
Role of right pregenual anterior cingulate cortex in self-conscious emotional reactivity.
Sturm, Virginia E; Sollberger, Marc; Seeley, William W; Rankin, Katherine P; Ascher, Elizabeth A; Rosen, Howard J; Miller, Bruce L; Levenson, Robert W
2013-04-01
Self-conscious emotions such as embarrassment arise when one's actions fail to meet salient social expectations and are accompanied by marked physiological and behavioral activation. We investigated the neural correlates of self-conscious emotional reactivity in 27 patients with behavioral variant frontotemporal dementia (bvFTD), a neurodegenerative disease that disrupts self-conscious emotion and targets brain regions critical for emotional functioning early in the disease course, and in 33 healthy older controls. Subjects participated in an embarrassing karaoke task in which they watched a video clip of themselves singing. They also watched a sad film clip; these data were used to control for non-self-conscious emotional reactivity in response to audiovisual stimuli. Using Freesurfer to quantify regional brain volumes from structural magnetic resonance imaging, right pregenual anterior cingulate cortex (pACC) gray matter volume was the only brain region that was a significant predictor of self-conscious emotion. Smaller pACC volume was associated with attenuated physiological and behavioral self-conscious emotional reactivity, and this relationship was not specific to diagnosis. We argue that these results reflect the significant role that right pACC plays in the visceromotor responding that accompanies self-conscious emotion and that neurodegeneration in this region may underlie the self-conscious emotional decline seen in bvFTD.
Zilverstand, Anna; Sorger, Bettina; Slaats-Willemse, Dorine; Kan, Cornelis C; Goebel, Rainer; Buitelaar, Jan K
2017-01-01
Attention Deficit Hyperactivity Disorder (ADHD) is characterized by poor cognitive control/attention and hypofunctioning of the dorsal anterior cingulate cortex (dACC). In the current study, we investigated for the first time whether real-time fMRI neurofeedback (rt-fMRI) training targeted at increasing activation levels within dACC in adults with ADHD leads to a reduction of clinical symptoms and improved cognitive functioning. An exploratory randomized controlled treatment study with blinding of the participants was conducted. Participants with ADHD (n = 7 in the neurofeedback group, and n = 6 in the control group) attended four weekly MRI training sessions (60-min training time/session), during which they performed a mental calculation task at varying levels of difficulty, in order to learn how to up-regulate dACC activation. Only neurofeedback participants received continuous feedback information on actual brain activation levels within dACC. Before and after the training, ADHD symptoms and relevant cognitive functioning was assessed. Results showed that both groups achieved a significant increase in dACC activation levels over sessions. While there was no significant difference between the neurofeedback and control group in clinical outcome, neurofeedback participants showed stronger improvement on cognitive functioning. The current study demonstrates the general feasibility of the suggested rt-fMRI neurofeedback training approach as a potential novel treatment option for ADHD patients. Due to the study's small sample size, potential clinical benefits need to be further investigated in future studies. ISRCTN12390961.
Feasibility of neuro-morphic computing to emulate error-conflict based decision making.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Branch, Darren W.
2009-09-01
A key aspect of decision making is determining when errors or conflicts exist in information and knowing whether to continue or terminate an action. Understanding the error-conflict processing is crucial in order to emulate higher brain functions in hardware and software systems. Specific brain regions, most notably the anterior cingulate cortex (ACC) are known to respond to the presence of conflicts in information by assigning a value to an action. Essentially, this conflict signal triggers strategic adjustments in cognitive control, which serve to prevent further conflict. The most probable mechanism is the ACC reports and discriminates different types of feedback,more » both positive and negative, that relate to different adaptations. Unique cells called spindle neurons that are primarily found in the ACC (layer Vb) are known to be responsible for cognitive dissonance (disambiguation between alternatives). Thus, the ACC through a specific set of cells likely plays a central role in the ability of humans to make difficult decisions and solve challenging problems in the midst of conflicting information. In addition to dealing with cognitive dissonance, decision making in high consequence scenarios also relies on the integration of multiple sets of information (sensory, reward, emotion, etc.). Thus, a second area of interest for this proposal lies in the corticostriatal networks that serve as an integration region for multiple cognitive inputs. In order to engineer neurological decision making processes in silicon devices, we will determine the key cells, inputs, and outputs of conflict/error detection in the ACC region. The second goal is understand in vitro models of corticostriatal networks and the impact of physical deficits on decision making, specifically in stressful scenarios with conflicting streams of data from multiple inputs. We will elucidate the mechanisms of cognitive data integration in order to implement a future corticostriatal-like network in silicon devices for improved decision processing.« less
Pedagogical Merit Review of Animal Use for Education in Canada
Griffin, Gilly
2016-01-01
There are two components to the review of animal based protocols in Canada: review for the merit of the study itself, and review of the ethical acceptability of the work. Despite the perceived importance for the quality assurance these reviews provide; there are few studies of the peer-based merit review system for animal-based protocols for research and education. Institutional animal care committees (ACC)s generally rely on the external peer review of scientific merit for animal-based research. In contrast, peer review for animal based teaching/training is dependent on the review of pedagogical merit carried out by the ACC itself or another committee within the institution. The objective of this study was to evaluate the views of ACC members about current practices and policies as well as alternate policies for the review of animal based teaching/training. We conducted a national web-based survey of ACC members with both quantitative and qualitative response options. Responses from 167 ACC members indicated broad concerns about administrative burden despite strong support for both the current and alternate policies. Participants’ comments focused mostly on the merit review process (54%) relative to the efficiency (21%), impact (13%), and other (12%) aspects of evaluation. Approximately half (49%) of the comments were classified into emergent themes that focused on some type of burden: burden from additional pedagogical merit review (16%), a limited need for the review (12%), and a lack of resources (expertise 11%; people/money 10%). Participants indicated that the current system for pedagogical merit review is effective (60%); but most also indicated that there was at least some challenge (86%) with the current peer review process. There was broad support for additional guidance on the justification, criteria, types of animal use, and objectives of pedagogical merit review. Participants also supported the ethical review and application of the Three Rs in the review process. A clear priority from participants in the survey was updating guidance to better facilitate the merit review process of animal-based protocols for education. Balancing the need for improved guidance with the reality of limited resources at local institutions will be essential to do this successfully; a familiar dilemma to both scientists and policy makers alike. PMID:27352243
Pedagogical Merit Review of Animal Use for Education in Canada.
Avey, Marc T; Griffin, Gilly
2016-01-01
There are two components to the review of animal based protocols in Canada: review for the merit of the study itself, and review of the ethical acceptability of the work. Despite the perceived importance for the quality assurance these reviews provide; there are few studies of the peer-based merit review system for animal-based protocols for research and education. Institutional animal care committees (ACC)s generally rely on the external peer review of scientific merit for animal-based research. In contrast, peer review for animal based teaching/training is dependent on the review of pedagogical merit carried out by the ACC itself or another committee within the institution. The objective of this study was to evaluate the views of ACC members about current practices and policies as well as alternate policies for the review of animal based teaching/training. We conducted a national web-based survey of ACC members with both quantitative and qualitative response options. Responses from 167 ACC members indicated broad concerns about administrative burden despite strong support for both the current and alternate policies. Participants' comments focused mostly on the merit review process (54%) relative to the efficiency (21%), impact (13%), and other (12%) aspects of evaluation. Approximately half (49%) of the comments were classified into emergent themes that focused on some type of burden: burden from additional pedagogical merit review (16%), a limited need for the review (12%), and a lack of resources (expertise 11%; people/money 10%). Participants indicated that the current system for pedagogical merit review is effective (60%); but most also indicated that there was at least some challenge (86%) with the current peer review process. There was broad support for additional guidance on the justification, criteria, types of animal use, and objectives of pedagogical merit review. Participants also supported the ethical review and application of the Three Rs in the review process. A clear priority from participants in the survey was updating guidance to better facilitate the merit review process of animal-based protocols for education. Balancing the need for improved guidance with the reality of limited resources at local institutions will be essential to do this successfully; a familiar dilemma to both scientists and policy makers alike.
Neurons in Anterior Cingulate Cortex Multiplex Information about Reward and Action
Hayden, Benjamin Y.; Platt, Michael L.
2010-01-01
The dorsal anterior cingulate cortex (dACC) is thought to play a critical role in forming associations between rewards and actions. Currently available physiological data, however, remain inconclusive regarding the question of whether dACC neurons carry information linking particular actions to reward or, instead, encode abstract reward information independent of specific actions. Here we show that firing rates of a majority of dACC neurons in a population studied in an eight-option variably rewarded choice task were sensitive to both saccade direction and reward value. Furthermore, the influences of reward and saccade direction on neuronal activity were roughly equal in magnitude over the range of rewards tested and were statistically independent. Our results indicate that dACC neurons multiplex information about both reward and action, endorsing the idea that this area links motivational outcomes to behavior and undermining the notion that its neurons solely contribute to reward processing in the abstract. PMID:20203193
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yip, Wingkip; Dong, Jianguo,; Yang, Shang Fa
Tomato ACC synthase is inactivated by its substrate SAM, with the moiety of aminobutyrate being covalently linked to ACC synthase during the catalytic reactions. A partial purified ACC synthase (the catalytic activity 100 {mu}mol/h{center dot}mg protein) from pellets of apple extract was incubated with (3,4{sup 14}C) SAM. Only one radioactive peak was revealed in a C-4 reverse phase HPLC and one radioactive band on SDS-PAGE with an M.W. of 48 kDa. Apple ACC synthase in native form is resistant to V8, {alpha}-chromtrypsin and carboxylpeptidase A digestion, but effectively inactivated by trypsin and ficin, as demonstrated by both the activity assaymore » and SAM labeling. The radioactive protein cut from the SDS-PAGE was injected to three mice, two of the mice showed responses to the protein in western blot analysis. The antibodies from mice is currently under characterization.« less
A Microscale View of Mixing and Overturning Across the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Naveira Garabato, A.; Polzin, K. L.; Ferrari, R. M.; Zika, J. D.; Forryan, A.
2014-12-01
The meridional overturning circulation and stratication of the global ocean are shaped critically by processes in the Southern Ocean. The zonally unblocked nature of the Antarctic Circumpolar Current (ACC) confers the region with a set of special dynamics that ultimately results in the focussing therein of large vertical exchanges between layers spanning the global ocean pycnocline. These vertical exchanges are thought to be mediated by oceanic turbulent motions (associated with mesoscale eddies and small-scale turbulence), yet the vastness of the Southern Ocean and the sparse and intermittent nature of turbulent processes make their relative roles and large-scale impacts extremely difficult to assess.Here, we address the problem from a new angle, and use measurements of the centimetre-scale signatures of mesoscale eddies and small-scale turbulence obtained during the DIMES experiment to determine the contributions of those processes to sustaining large-scale meridional overturning across the ACC. We find that mesoscale eddies and small-scale turbulence play complementary roles in forcing a meridional circulation of O(1 mm / s) across the Southern Ocean, and that their roles are underpinned by distinct and abrupt variations in the rates at which they mix water parcels. The implications for our understanding of the Southern Ocean circulation's sensitivity to climatic change will be discussed.
Erickson, Kirk I; Milham, Michael P; Colcombe, Stanley J; Kramer, Arthur F; Banich, Marie T; Webb, Andrew; Cohen, Neal J
2004-02-01
We investigated the relationship between behavioral measures of conflict and the degree of activity in the anterior cingulate cortex (ACC). We reanalyzed an existing data set that employed the Stroop task using functional magnetic resonance imaging [Milham et al., Brain Cogn 2002;49:277-296]. Although we found no changes in the behavioral measures of conflict from the first to the second half of task performance, we found a reliable reduction in the activity of the anterior cingulate cortex. This result suggests the lack of a strong relationship between behavioral measurements of conflict and anterior cingulate activity. A concomitant increase in dorsolateral prefrontal cortex activity was also found, which may reflect a tradeoff in the neural substrates involved in supporting conflict resolution, detection, or monitoring processes. A second analysis of the data revealed that the duration of an experiment can dramatically affect interpretations of the results, including the roles in which particular regions are thought to play in cognition. These results are discussed in relation to current conceptions of ACC's role in attentional control. In addition, we discuss the implication of our results with current conceptions of conflict and of its instantiation in the brain. Hum. Brain Mapping 21:96-105, 2004. Copyright 2003 Wiley-Liss, Inc.
NASA Astrophysics Data System (ADS)
Lamy, F.; Arz, H. W.; Kilian, R.; Baeza Urrea, O.; Caniupan, M.; Kissel, C.; Lange, C.
2012-04-01
The Antarctic Circumpolar Current (ACC) plays an essential role in the thermohaline circulation and global climate. Today a large volume of ACC water passes through the Drake Passage, a major geographic constrain for the circumpolar flow. Satellite tracked surface drifters have shown that Subantarctic Surface water of the ACC is transported northeastward across the Southeast Pacific from ~53°S/100°W towards the Chilean coast at ~40°S/75°W where surface waters bifurcate and flow northward into the Peru Chile Current (PCC) finally reaching the Eastern Tropical Pacific, and southwards into the Cape Horn Current (CHC). The CHC thus transports a significant amount of northern ACC water towards the Drake Passage and reaches surface current velocities of up to 35 cm/s within a narrow belt of ~100-150 km width off the coast. Also at deeper water levels, an accelerated southward flow occurs along the continental slope off southernmost South America that likewise substantially contributes to the Drake Passage throughflow. Here we report on high resolution geochemical and grain-size records from core MD07-3128 (53°S; 1032 m water depth) which has been retrieved from the upper continental slope off the Pacific entrance of the Magellan Strait beneath the CHC. Magnetic grain-sizes and grain-size distributions of the terrigenous fraction reveal large amplitude changes between the Holocene and the last glacial, as well as millennial-scale variability (most pronounced during Marine Isotope Stage). Magnetic grain-sizes, silt/clay ratios, fine sand contents, sortable silt contents, and sortable silt mean grain-sizes are substantially higher during the Holocene suggesting strongly enhanced current activity. The high absolute values imply flow speeds larger than 25 cm/s as currently observed in the CHC surface current. Furthermore, winnowing processes through bottom current activity and changes in the availability of terrigenous material (ice-sheet extension and related supply of silt/clay, efficiency of the fjords in trapping sediment) might have contributed to the observed grain-size variations. Assuming that surface and bottom current strength changes are the major controlling factors, our data suggest a strongly enhanced CHC and deeper flow during the Holocene compared to the mean of the last glacial. During MIS 3, several phases of stronger current flow mostly correlate with warm sea surface temperatures at the site and, within age uncertainties, with millennial-scale warm phases in Antarctic ice cores. Taken together our data can be interpreted in terms of strongly reduced contributions of northern ACC water to the Drake Passage throughflow during the glacial in general and during millennial-scale cold phases in particular. At the same time, advection of northern ACC water into the PCC was probably enhanced. These results are consistent with model runs showing largely reduced volume transport through the Drake Passage during the last glacial maximum and an increasing throughflow during the last deglaciation that might have affected the strengthening of the Atlantic Meridional Overturning Circulation.
High intensity interval training improves liver and adipose tissue insulin sensitivity
Marcinko, Katarina; Sikkema, Sarah R.; Samaan, M. Constantine; Kemp, Bruce E.; Fullerton, Morgan D.; Steinberg, Gregory R.
2015-01-01
Objective Endurance exercise training reduces insulin resistance, adipose tissue inflammation and non-alcoholic fatty liver disease (NAFLD), an effect often associated with modest weight loss. Recent studies have indicated that high-intensity interval training (HIIT) lowers blood glucose in individuals with type 2 diabetes independently of weight loss; however, the organs affected and mechanisms mediating the glucose lowering effects are not known. Intense exercise increases phosphorylation and inhibition of acetyl-CoA carboxylase (ACC) by AMP-activated protein kinase (AMPK) in muscle, adipose tissue and liver. AMPK and ACC are key enzymes regulating fatty acid metabolism, liver fat content, adipose tissue inflammation and insulin sensitivity but the importance of this pathway in regulating insulin sensitivity with HIIT is unknown. Methods In the current study, the effects of 6 weeks of HIIT were examined using obese mice with serine–alanine knock-in mutations on the AMPK phosphorylation sites of ACC1 and ACC2 (AccDKI) or wild-type (WT) controls. Results HIIT lowered blood glucose and increased exercise capacity, food intake, basal activity levels, carbohydrate oxidation and liver and adipose tissue insulin sensitivity in HFD-fed WT and AccDKI mice. These changes occurred independently of weight loss or reductions in adiposity, inflammation and liver lipid content. Conclusions These data indicate that HIIT lowers blood glucose levels by improving adipose and liver insulin sensitivity independently of changes in adiposity, adipose tissue inflammation, liver lipid content or AMPK phosphorylation of ACC. PMID:26909307
Rousseau-Gueutin, Mathieu; Huang, Xun; Higginson, Emily; Ayliffe, Michael; Day, Anil; Timmis, Jeremy N.
2013-01-01
Eukaryotic cells originated when an ancestor of the nucleated cell engulfed bacterial endosymbionts that gradually evolved into the mitochondrion and the chloroplast. Soon after these endosymbiotic events, thousands of ancestral prokaryotic genes were functionally transferred from the endosymbionts to the nucleus. This process of functional gene relocation, now rare in eukaryotes, continues in angiosperms. In this article, we show that the chloroplastic acetyl-CoA carboxylase subunit (accD) gene that is present in the plastome of most angiosperms has been functionally relocated to the nucleus in the Campanulaceae. Surprisingly, the nucleus-encoded accD transcript is considerably smaller than the plastidic version, consisting of little more than the carboxylase domain of the plastidic accD gene fused to a coding region encoding a plastid targeting peptide. We verified experimentally the presence of a chloroplastic transit peptide by showing that the product of the nuclear accD fused to green fluorescent protein was imported in the chloroplasts. The nuclear gene regulatory elements that enabled the erstwhile plastidic gene to become functional in the nuclear genome were identified, and the evolution of the intronic and exonic sequences in the nucleus is described. Relocation and truncation of the accD gene is a remarkable example of the processes underpinning endosymbiotic evolution. PMID:23435694
A human brain network derived from coma-causing brainstem lesions.
Fischer, David B; Boes, Aaron D; Demertzi, Athena; Evrard, Henry C; Laureys, Steven; Edlow, Brian L; Liu, Hesheng; Saper, Clifford B; Pascual-Leone, Alvaro; Fox, Michael D; Geerling, Joel C
2016-12-06
To characterize a brainstem location specific to coma-causing lesions, and its functional connectivity network. We compared 12 coma-causing brainstem lesions to 24 control brainstem lesions using voxel-based lesion-symptom mapping in a case-control design to identify a site significantly associated with coma. We next used resting-state functional connectivity from a healthy cohort to identify a network of regions functionally connected to this brainstem site. We further investigated the cortical regions of this network by comparing their spatial topography to that of known networks and by evaluating their functional connectivity in patients with disorders of consciousness. A small region in the rostral dorsolateral pontine tegmentum was significantly associated with coma-causing lesions. In healthy adults, this brainstem site was functionally connected to the ventral anterior insula (AI) and pregenual anterior cingulate cortex (pACC). These cortical areas aligned poorly with previously defined resting-state networks, better matching the distribution of von Economo neurons. Finally, connectivity between the AI and pACC was disrupted in patients with disorders of consciousness, and to a greater degree than other brain networks. Injury to a small region in the pontine tegmentum is significantly associated with coma. This brainstem site is functionally connected to 2 cortical regions, the AI and pACC, which become disconnected in disorders of consciousness. This network of brain regions may have a role in the maintenance of human consciousness. © 2016 American Academy of Neurology.
A human brain network derived from coma-causing brainstem lesions
Boes, Aaron D.; Demertzi, Athena; Evrard, Henry C.; Laureys, Steven; Edlow, Brian L.; Liu, Hesheng; Saper, Clifford B.; Pascual-Leone, Alvaro; Geerling, Joel C.
2016-01-01
Objective: To characterize a brainstem location specific to coma-causing lesions, and its functional connectivity network. Methods: We compared 12 coma-causing brainstem lesions to 24 control brainstem lesions using voxel-based lesion-symptom mapping in a case-control design to identify a site significantly associated with coma. We next used resting-state functional connectivity from a healthy cohort to identify a network of regions functionally connected to this brainstem site. We further investigated the cortical regions of this network by comparing their spatial topography to that of known networks and by evaluating their functional connectivity in patients with disorders of consciousness. Results: A small region in the rostral dorsolateral pontine tegmentum was significantly associated with coma-causing lesions. In healthy adults, this brainstem site was functionally connected to the ventral anterior insula (AI) and pregenual anterior cingulate cortex (pACC). These cortical areas aligned poorly with previously defined resting-state networks, better matching the distribution of von Economo neurons. Finally, connectivity between the AI and pACC was disrupted in patients with disorders of consciousness, and to a greater degree than other brain networks. Conclusions: Injury to a small region in the pontine tegmentum is significantly associated with coma. This brainstem site is functionally connected to 2 cortical regions, the AI and pACC, which become disconnected in disorders of consciousness. This network of brain regions may have a role in the maintenance of human consciousness. PMID:27815400
Amemori, Ken-ichi; Amemori, Satoko; Graybiel, Ann M
2015-02-04
The judgment of whether to accept or to reject an offer is determined by positive and negative affect related to the offer, but affect also induces motivational responses. Rewarding and aversive cues influence the firing rates of many neurons in primate prefrontal and cingulate neocortical regions, but it still is unclear whether neurons in these regions are related to affective judgment or to motivation. To address this issue, we recorded simultaneously the neuronal spike activities of single units in the dorsolateral prefrontal cortex (dlPFC) and the anterior cingulate cortex (ACC) of macaque monkeys as they performed approach-avoidance (Ap-Av) and approach-approach (Ap-Ap) decision-making tasks that can behaviorally dissociate affective judgment and motivation. Notably, neurons having activity correlated with motivational condition could be distinguished from neurons having activity related to affective judgment, especially in the Ap-Av task. Although many neurons in both regions exhibited similar, selective patterns of task-related activity, we found a larger proportion of neurons activated in low motivational conditions in the dlPFC than in the ACC, and the onset of this activity was significantly earlier in the dlPFC than in the ACC. Furthermore, the temporal onsets of affective judgment represented by neuronal activities were significantly slower in the low motivational conditions than in the other conditions. These findings suggest that motivation and affective judgment both recruit dlPFC and ACC neurons but with differential degrees of involvement and timing. Copyright © 2015 the authors 0270-6474/15/351939-15$15.00/0.
Clark, Uraina S.; Walker, Keenan A.; Cohen, Ronald A.; Devlin, Kathryn N.; Folkers, Anna M.; Pina, Mathew M.; Tashima, Karen T.
2015-01-01
Impaired facial emotion recognition abilities in HIV+ patients are well documented, but little is known about the neural etiology of these difficulties. We examined the relation of facial emotion recognition abilities to regional brain volumes in 44 HIV-positive (HIV+) and 44 HIV-negative control (HC) adults. Volumes of structures implicated in HIV− associated neuropathology and emotion recognition were measured on MRI using an automated segmentation tool. Relative to HC, HIV+ patients demonstrated emotion recognition impairments for fearful expressions, reduced anterior cingulate cortex (ACC) volumes, and increased amygdala volumes. In the HIV+ group, fear recognition impairments correlated significantly with ACC, but not amygdala volumes. ACC reductions were also associated with lower nadir CD4 levels (i.e., greater HIV-disease severity). These findings extend our understanding of the neurobiological substrates underlying an essential social function, facial emotion recognition, in HIV+ individuals and implicate HIV-related ACC atrophy in the impairment of these abilities. PMID:25744868
Sinonasal adenoid cystic carcinoma: Treatment outcomes and association with human papillomavirus.
Miller, Eric D; Blakaj, Dukagjin M; Swanson, Benjamin J; Xiao, Weihong; Gillison, Maura L; Wei, Lai; Bhatt, Aashish D; Diavolitsis, Virginia M; Wobb, Jessica L; Kang, Stephen Y; Carrau, Ricardo L; Grecula, John C
2017-07-01
The purpose of this study was to review long-term outcomes of sinonasal adenoid cystic carcinoma (ACC) and to clarify its association with human papillomavirus (HPV). The medical records of 23 patients with sinonasal ACC treated with primary surgical resection between 1998 and 2013 were reviewed. Tissue specimens were available for 17 patients. The p16 testing was performed using immunohistochemistry (IHC), and HPV infection was determined using quantitative polymerase chain reaction (PCR) with primers targeting the E6/E7 region. Two of the 17 samples showed strong and diffuse p16 staining, whereas the remaining 15 cases showed p16-positivity isolated to the luminal cells. Only one of the p16-positive cases was positive for HPV. The 5-year local failure, disease-free survival (DFS), and overall survival (OS) were 51%, 52%, and 62%, respectively. Local failures are common with advanced sinonasal ACC, and the association of HPV with true sinonasal ACC is low. © 2017 Wiley Periodicals, Inc.
Relation of obesity to neural activation in response to food commercials.
Gearhardt, Ashley N; Yokum, Sonja; Stice, Eric; Harris, Jennifer L; Brownell, Kelly D
2014-07-01
Adolescents view thousands of food commercials annually, but the neural response to food advertising and its association with obesity is largely unknown. This study is the first to examine how neural response to food commercials differs from other stimuli (e.g. non-food commercials and television show) and to explore how this response may differ by weight status. The blood oxygen level-dependent functional magnetic resonance imaging activation was measured in 30 adolescents ranging from lean to obese in response to food and non-food commercials imbedded in a television show. Adolescents exhibited greater activation in regions implicated in visual processing (e.g. occipital gyrus), attention (e.g. parietal lobes), cognition (e.g. temporal gyrus and posterior cerebellar lobe), movement (e.g. anterior cerebellar cortex), somatosensory response (e.g. postcentral gyrus) and reward [e.g. orbitofrontal cortex and anterior cingulate cortex (ACC)] during food commercials. Obese participants exhibited less activation during food relative to non-food commercials in neural regions implicated in visual processing (e.g. cuneus), attention (e.g. posterior cerebellar lobe), reward (e.g. ventromedial prefrontal cortex and ACC) and salience detection (e.g. precuneus). Obese participants did exhibit greater activation in a region implicated in semantic control (e.g. medial temporal gyrus). These findings may inform current policy debates regarding the impact of food advertising to minors. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Mergelsberg, S. T.; Ulrich, R. N.; Michel, F. M.; Dove, P. M.
2017-12-01
Recent advances in high-resolution imaging show the widespreadd occurrence of multistep pathways to mineralization in biological and geological settings (De Yoreo et al., 2015, Science). For example, carbonate biomineralization often involves precipitation of amorphous calcium carbonate (ACC) as a reactive intermediate that subsequently transforms to crystalline products with diverse structures. Although current carbonate mineral proxies are based upon the composition of final crystalline products, the final signatures may be recording the properties of the initial amorphous phase. Thus, it is critical to establish the physical properties of ACC and understand the factors that influence its evolution to final products at conditions that approximate biological environments. This disconnect limits our ability to build a process-based understanding of when/how minor and trace elements are recorded in mineral composition proxies. In this experimental study, we quantified the chemical and physical properties of ACC and its evolution to final products. We first determined ACC solubility under controlled chemical conditions using a new type of flow-through reactor developed by our research group (Blue and Dove, 2015, GCA; Blue et al., 2017, GCA). The experimental design varied Mg concentration and total alkalinity while maintaining a mild pH that approximates biological environments. ACC solubility was measured at specific time points during the precipitation (from super- and undersaturated conditions) and during its subsequent evolution. Parallel experiments characterized the structure of the corresponding amorphous products using in situ pair distribution function (PDF) and small-angle x-ray scattering (SAXS) analyses. The measurements demonstrate at least two types of ACC can be produced by tuning Mg concentration and alkalinity. Each "phase" exhibits distinct short-range ordering that demonstrates structure-specific solubility. We also find temporal changes in the short-range order of each type of ACC that are dependent upon Mg content. Insights from this study hold promise for quantifying the chemical and structural properties of ACC and reconcile discrepancies in the literature.
Abend, Rany; Sar-El, Roy; Gonen, Tal; Jalon, Itamar; Vaisvaser, Sharon; Bar-Haim, Yair; Hendler, Talma
2018-05-09
Implicit regulation of emotions involves medial-prefrontal cortex (mPFC) regions exerting regulatory control over limbic structures. Diminished regulation relates to aberrant mPFC functionality and psychopathology. Establishing means of modulating mPFC functionality could benefit research on emotion and its dysregulation. Here, we tested the capacity of transcranial direct current stimulation (tDCS) targeting mPFC to modulate subjective emotional states by facilitating implicit emotion regulation. Stimulation was applied concurrently with functional magnetic resonance imaging to validate its neurobehavioral effect. Sixteen participants were each scanned twice, counterbalancing active and sham tDCS application, while undergoing negative mood induction (clips featuring negative vs. neutral contents). Effects of stimulation on emotional experience were assessed using subjective and neural measures. Subjectively, active stimulation led to significant reduction in reported intensity of experienced emotions to negatively valenced (p = 0.005) clips but not to neutral clips (p > 0.99). Active stimulation further mitigated a rise in stress levels from pre- to post-induction (sham: p = 0.004; active: p = 0.15). Neurally, stimulation increased activation in mPFC regions associated with implicit emotion regulation (ventromedial-prefrontal cortex; subgenual anterior-cingulate cortex, sgACC), and in ventral striatum, a core limbic structure (all ps < 0.05). Stimulation also altered functional connectivity (assessed using whole-brain psycho-physiological interaction) between these regions, and with additional limbic regions. Stimulation-induced sgACC activation correlated with reported emotion intensity and depressive symptoms (rs > 0.64, ps < 0.018), suggesting individual differences in stimulation responsivity. Results of this study indicate the potential capacity of tDCS to facilitate brain activation in mPFC regions underlying implicit regulation of emotion and accordingly modulate subjective emotional experiences. © 2018 International Neuromodulation Society.
Minzenberg, Michael J.; Fan, Jin; New, Antonia S.; Tang, Cheuk Y.; Siever, Larry J.
2007-01-01
Clinical hallmarks of borderline personality disorder (BPD) include social and emotional dysregulation. We tested a model of frontolimbic dysfunction in facial emotion processing in BPD. Groups of 12 unmedicated adults with BPD by DSM-IV and 12 demographically-matched healthy controls (HC) viewed facial expressions (Conditions) of neutral emotion, fear and anger, and made gender discriminations during rapid event-related functional magnetic resonance imaging (fMRI). Analysis of variance of Region of Interest signal change revealed a statistically significant effect of the Group-by-Region-by-Condition interaction. This was due to the BPD group exhibiting a significantly larger magnitude of deactivation (relative to HC) in the bilateral rostral/subgenual anterior cingulate cortex (ACC) to fear and in the left ACC to fear minus neutral; and significantly greater activation in the right amygdala to fear minus neutral. There were no significant between-group differences in ROI signal change in response to anger. In voxel-wise analyses constrained within these ROIs, the BPD group exhibited significant changes in the fear minus neutral contrast, with relatively less activation in the bilateral rostral/subgenual ACC, and greater activation in the right amygdala. In the anger minus neutral contrast this pattern was reversed, with the BPD group showing greater activation in the bilateral rostral/subgenual ACC and less activation in the bilateral amygdala. We conclude that adults with BPD exhibit changes in fronto-limbic activity in the processing of fear stimuli, with exaggerated amygdala response and impaired emotion-modulation of ACC activity. The neural substrates underlying processing of anger may also be altered. These changes may represent an expression of the volumetric and serotonergic deficits observed in these brain areas in BPD. PMID:17601709
Goji, Aya; Ito, Hiromichi; Mori, Kenji; Harada, Masafumi; Hisaoka, Sonoka; Toda, Yoshihiro; Mori, Tatsuo; Abe, Yoko; Miyazaki, Masahito; Kagami, Shoji
2017-01-01
Proton magnetic resonance spectroscopy (1H MRS) is a noninvasive neuroimaging method to quantify biochemical metabolites in vivo and it can serve as a powerful tool to monitor neurobiochemical profiles in the brain. Asperger's syndrome (AS) is a type of autism spectrum disorder, which is characterized by impaired social skills and restrictive, repetitive patterns of interest and activities, while intellectual levels and language skills are relatively preserved. Despite clinical aspects have been well-characterized, neurometabolic profiling in the brain of AS remains to be clear. The present study used proton magnetic resonance spectroscopy (1H MRS) to investigate whether pediatric AS is associated with measurable neurometabolic abnormalities that can contribute new information on the neurobiological underpinnings of the disorder. Study participants consisted of 34 children with AS (2-12 years old; mean age 5.2 (±2.0); 28 boys) and 19 typically developed children (2-11 years old; mean age 5.6 (±2.6); 12 boys) who served as the normal control group. The 1H MRS data were obtained from two regions of interest: the anterior cingulate cortex (ACC) and left cerebellum. In the ACC, levels of N-acetylaspartate (NAA), total creatine (tCr), total choline-containing compounds (tCho) and myo-Inositol (mI) were significantly decreased in children with AS compared to controls. On the other hand, no significant group differences in any of the metabolites were found in the left cerebellum. Neither age nor sex accounted for the metabolic findings in the regions. The finding of decreased levels of NAA, tCr, tCho, and mI in the ACC but not in left cerebellar voxels in the AS, suggests a lower ACC neuronal density in the present AS cohort compared to controls.
Minzenberg, Michael J; Fan, Jin; New, Antonia S; Tang, Cheuk Y; Siever, Larry J
2007-08-15
Clinical hallmarks of borderline personality disorder (BPD) include social and emotional dysregulation. We tested a model of fronto-limbic dysfunction in facial emotion processing in BPD. Groups of 12 unmedicated adults with BPD by DSM-IV and 12 demographically-matched healthy controls (HC) viewed facial expressions (Conditions) of neutral emotion, fear and anger, and made gender discriminations during rapid event-related functional magnetic resonance imaging (fMRI). Analysis of variance of Region of Interest signal change revealed a statistically significant effect of the Group-by-Region-by-Condition interaction. This was due to the BPD group exhibiting a significantly larger magnitude of deactivation (relative to HC) in the bilateral rostral/subgenual anterior cingulate cortex (ACC) to fear and in the left ACC to fear minus neutral; and significantly greater activation in the right amygdala to fear minus neutral. There were no significant between-group differences in ROI signal change in response to anger. In voxel-wise analyses constrained within these ROIs, the BPD group exhibited significant changes in the fear minus neutral contrast, with relatively less activation in the bilateral rostral/subgenual ACC, and greater activation in the right amygdala. In the anger minus neutral contrast this pattern was reversed, with the BPD group showing greater activation in the bilateral rostral/subgenual ACC and less activation in the bilateral amygdala. We conclude that adults with BPD exhibit changes in fronto-limbic activity in the processing of fear stimuli, with exaggerated amygdala response and impaired emotion-modulation of ACC activity. The neural substrates underlying processing of anger may also be altered. These changes may represent an expression of the volumetric and serotonergic deficits observed in these brain areas in BPD.
Murray, Donna E; Durazzo, Timothy C; Schmidt, Thomas P; Abé, Christoph; Guydish, Joseph; Meyerhoff, Dieter J
2016-01-01
Objective Proton magnetic resonance spectroscopy (1H MRS) in opiate dependence showed abnormalities in neuronal viability and glutamate concentration in the anterior cingulate cortex (ACC). Metabolite levels in dorsolateral prefrontal cortex (DLPFC) or orbitofrontal cortex (OFC) and their neuropsychological correlates have not been investigated in opiate dependence. Methods Single-volume proton MRS at 4 Tesla and neuropsychological testing were conducted in 21 opiate-dependent individuals (OD) on buprenorphine maintenance therapy. Results were compared to 28 controls (CON) and 35 alcohol-dependent individuals (ALC), commonly investigated treatment-seekers providing context for OD evaluation. Metabolite concentrations were measured from ACC, DLPFC, OFC and parieto-occipital cortical (POC) regions. Results Compared to CON, OD had lower concentrations of N-acetylaspartate (NAA), glutamate (Glu), creatine +phosphocreatine (Cr) and myo-Inositol (mI) in the DLPFC and lower NAA, Cr, and mI in the ACC. OD, ALC, and CON were equivalent on metabolite levels in the POC and γ-aminobutyric acid (GABA) concentration did not differ between groups in any region. In OD, prefrontal metabolite deficits in ACC Glu as well as DLPFC NAA and choline containing metabolites (Cho) correlated with poorer working memory, executive and visuospatial functioning; metabolite deficits in DLPFC Glu and ACC GABA and Cr correlated with substance use measures. In the OFC of OD, Glu and choline-containing metabolites were elevated and lower Cr concentration related to higher nonplanning impulsivity. Compared to 3 week abstinent ALC, OD had significant DLPFC metabolite deficits. Conclusion The anterior frontal metabolite profile of OD differed significantly from that of CON and ALC. The frontal lobe metabolite abnormalities in OD and their neuropsychological correlates may play a role in treatment outcome and could be explored as specific targets for improved OD treatment. PMID:27695638
Ley, C J; Ekman, S; Hansson, K; Björnsdóttir, S; Boyde, A
2014-03-25
Osteochondral lesions in the joints of the distal tarsal region of young Icelandic horses provide a natural model for the early stages of osteoarthritis (OA) in low-motion joints. We describe and characterise mineralised and non-mineralised osteochondral lesions in left distal tarsal region joint specimens from twenty-two 30 ±1 month-old Icelandic horses. Combinations of confocal scanning light microscopy, backscattered electron scanning electron microscopy (including, importantly, iodine staining) and three-dimensional microcomputed tomography were used on specimens obtained with guidance from clinical imaging. Lesion-types were described and classified into groups according to morphological features. Their locations in the hyaline articular cartilage (HAC), articular calcified cartilage (ACC), subchondral bone (SCB) and the joint margin tissues were identified and their frequency in the joints recorded. Associations and correlations between lesion-types were investigated for centrodistal joints only. In centrodistal joints the lesion-types HAC chondrocyte loss, HAC fibrillation, HAC central chondrocyte clusters, ACC arrest and ACC advance had significant associations and strong correlations. These lesion-types had moderate to high frequency in centrodistal joints but low frequencies in tarsometatarsal and talocalcaneal-centroquartal joints. Joint margin lesion-types had no significant associations with other lesion-types in the centrodistal joints but high frequency in both the centrodistal and tarsometatarsal joints. The frequency of SCB lesion-types in all joints was low. Hypermineralised infill phase lesion-types were detected. Our results emphasise close associations between HAC and ACC lesions in equine centrodistal joints and the importance of ACC lesions in the development of OA in low-motion compression-loaded equine joints.
Ebisch, Sjoerd J H; Mantini, Dante; Romanelli, Roberta; Tommasi, Marco; Perrucci, Mauro G; Romani, Gian Luca; Colom, Roberto; Saggino, Aristide
2013-09-01
The brain is organized into functionally specific networks as characterized by intrinsic functional relationships within discrete sets of brain regions. However, it is poorly understood whether such functional networks are dynamically organized according to specific task-states. The anterior insular cortex (aIC)-dorsal anterior cingulate cortex (dACC)/medial frontal cortex (mFC) network has been proposed to play a central role in human cognitive abilities. The present functional magnetic resonance imaging (fMRI) study aimed at testing whether functional interactions of the aIC-dACC/mFC network in terms of temporally correlated patterns of neural activity across brain regions are dynamically modulated by transitory, ongoing task demands. For this purpose, functional interactions of the aIC-dACC/mFC network are compared during two distinguishable fluid reasoning tasks, Visualization and Induction. The results show an increased functional coupling of bilateral aIC with visual cortices in the occipital lobe during the Visualization task, whereas coupling of mFC with right anterior frontal cortex was enhanced during the Induction task. These task-specific modulations of functional interactions likely reflect ability related neural processing. Furthermore, functional connectivity strength between right aIC and right dACC/mFC reliably predicts general task performance. The findings suggest that the analysis of long-range functional interactions may provide complementary information about brain-behavior relationships. On the basis of our results, it is proposed that the aIC-dACC/mFC network contributes to the integration of task-common and task-specific information based on its within-network as well as its between-network dynamic functional interactions. Copyright © 2013 Elsevier Inc. All rights reserved.
Distracted and down: neural mechanisms of affective interference in subclinical depression.
Kaiser, Roselinde H; Andrews-Hanna, Jessica R; Spielberg, Jeffrey M; Warren, Stacie L; Sutton, Bradley P; Miller, Gregory A; Heller, Wendy; Banich, Marie T
2015-05-01
Previous studies have shown that depressed individuals have difficulty directing attention away from negative distractors, a phenomenon known as affective interference. However, findings are mixed regarding the neural mechanisms and network dynamics of affective interference. The present study addressed these issues by comparing neural activation during emotion-word and color-word Stroop tasks in participants with varying levels of (primarily subclinical) depression. Depressive symptoms predicted increased activation to negative distractors in areas of dorsal anterior cingulate cortex (dACC) and posterior cingulate cortex (PCC), regions implicated in cognitive control and internally directed attention, respectively. Increased dACC activity was also observed in the group-average response to incongruent distractors, suggesting that dACC activity during affective interference is related to overtaxed cognitive control. In contrast, regions of PCC were deactivated across the group in response to incongruent distractors, suggesting that PCC activity during affective interference represents task-independent processing. A psychophysiological interaction emerged in which higher depression predicted more positively correlated activity between dACC and PCC during affective interference, i.e. greater connectivity between cognitive control and internal-attention systems. These findings suggest that, when individuals high in depression are confronted by negative material, increased attention to internal thoughts and difficulty shifting resources to the external world interfere with goal-directed behavior. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Gille, Sarah T.
1995-01-01
Geosat altimeter data and numerical model output are used to examine the circulation and dynamics of the Antarctic Circumpolar Current (ACC). The mean sea surface height across the ACC has been reconstructed from height variability measured by the altimeter, without assuming prior knowledge of the geoid. The results indicate locations for the Subantarctic and Polar Fronts which are consistent with in situ observations and indicate that the fronts are substantially steered by bathymetry. Detailed examination of spatial and temporal variability indicates a spatial decorrelation scale of 85 km and a temporal e-folding scale of 34 days. Empirical Orthogonal Function analysis suggests that the scales of motion are relatively short, occuring on 1000 km length-scales rather than basin or global scales. The momentum balance of the ACC has been investigated using output from the high resolution primitive equation model in combination with altimeter data. In the Semtner-Chervin quarter-degree general circulation model topographic form stress is the dominant process balancing the surface wind forcing. In stream coordinates, the dominant effect transporting momentum across the ACC is bibarmonic friction. Potential vorticity is considered on Montgomery streamlines in the model output and along surface streamlines in model and altimeter data. (AN)
Slaats-Willemse, Dorine; Kan, Cornelis C.; Goebel, Rainer; Buitelaar, Jan K.
2017-01-01
Attention Deficit Hyperactivity Disorder (ADHD) is characterized by poor cognitive control/attention and hypofunctioning of the dorsal anterior cingulate cortex (dACC). In the current study, we investigated for the first time whether real-time fMRI neurofeedback (rt-fMRI) training targeted at increasing activation levels within dACC in adults with ADHD leads to a reduction of clinical symptoms and improved cognitive functioning. An exploratory randomized controlled treatment study with blinding of the participants was conducted. Participants with ADHD (n = 7 in the neurofeedback group, and n = 6 in the control group) attended four weekly MRI training sessions (60-min training time/session), during which they performed a mental calculation task at varying levels of difficulty, in order to learn how to up-regulate dACC activation. Only neurofeedback participants received continuous feedback information on actual brain activation levels within dACC. Before and after the training, ADHD symptoms and relevant cognitive functioning was assessed. Results showed that both groups achieved a significant increase in dACC activation levels over sessions. While there was no significant difference between the neurofeedback and control group in clinical outcome, neurofeedback participants showed stronger improvement on cognitive functioning. The current study demonstrates the general feasibility of the suggested rt-fMRI neurofeedback training approach as a potential novel treatment option for ADHD patients. Due to the study’s small sample size, potential clinical benefits need to be further investigated in future studies. Trial Registration: ISRCTN12390961 PMID:28125735
Conflict adaptation in prefrontal cortex: now you see it, now you don't.
Kim, Chobok; Johnson, Nathan F; Gold, Brian T
2014-01-01
Daily life requires people to monitor and resolve conflict arising from distracting information irrelevant to current goals. The highly influential conflict monitoring theory (CMT) holds that the anterior cingulate cortex (ACC) detects conflict and subsequently triggers the dorsolateral prefrontal cortex (DLPFC) to regulate that conflict. Multiple lines of evidence have provided support for CMT. For example, performance is faster on incongruent trials that follow other incongruent trials (iI), and is accompanied by reduced ACC and increased DLPFC activation (the conflict adaptation effect). In this fMRI study, we explored whether ACC-DLPFC conflict signaling can result in behavioral adjustments beyond on-line contexts. Participants completed a modified version of the Stroop conflict adaptation paradigm which tested for conflict adaptation effects on the current (N) trial associated with not only the immediately preceding (N - 1) trial, but also 2-back (N - 2) trials. Results demonstrated evidence for direct relationships between ACC activity on N - 2 trials and both N trial DLPFC activity and behavioral adjustment when intervening trials were congruent (i.e., icI). In contrast, when N - 1 trials were incongruent (i.e., iiI), ACC-DLPFC signaling failed and conflict adaptation was absent. These results provide new evidence demonstrating that the conflict monitor-controller maintains previously experienced conflict in the service of subsequent behavioral adjustment. However, the processing of multiple, temporally proximal conflict signals takes a toll on the working memory (WM) system, which appears to require resetting in order to adapt our behavior to frequently changing environmental demands. Copyright © 2013 Elsevier Ltd. All rights reserved.
Stevens, Jennifer S; Ely, Timothy D; Sawamura, Takehito; Guzman, Dora; Bradley, Bekh; Ressler, Kerry J; Jovanovic, Tanja
2016-07-01
A deficit in the ability to inhibit fear has been proposed as a biomarker of posttraumatic stress disorder (PTSD). Previous research indicates that individuals with PTSD show reduced inhibition-related activation in rostral anterior cingulate cortex (rACC). The goal of the current study was to investigate differential influences of an early environmental risk factor for PTSD-childhood maltreatment-on inhibition-related brain function in individuals with PTSD versus trauma-exposed controls. Individuals with PTSD (n = 37) and trauma-exposed controls (n = 53) were recruited from the primary care waiting rooms of an urban public hospital in Atlanta, GA. Participants completed an inhibition task during fMRI, and reported childhood and adult traumatic experiences. The groups were matched for adult and child trauma load. We observed an interaction between childhood maltreatment severity and PTSD status in the rACC (P < .05, corrected), such that maltreatment was negatively associated with inhibition-related rACC activation in the PTSD group, but did not influence rACC activation in the TC group. Rostral ACC activation was associated with inhibition-related task performance in the TC group but not the PTSD group, suggesting a possible contribution to stress resilience. Findings highlight individual differences in neural function following childhood trauma, and point to inhibition-related activation in rostral ACC as a risk factor for PTSD. © 2016 Wiley Periodicals, Inc.
Goldstein, Rita Z; Woicik, Patricia A; Maloney, Thomas; Tomasi, Dardo; Alia-Klein, Nelly; Shan, Juntian; Honorio, Jean; Samaras, Dimitris; Wang, Ruiliang; Telang, Frank; Wang, Gene-Jack; Volkow, Nora D
2010-09-21
Anterior cingulate cortex (ACC) hypoactivations during cognitive demand are a hallmark deficit in drug addiction. Methylphenidate (MPH) normalizes cortical function, enhancing task salience and improving associated cognitive abilities, in other frontal lobe pathologies; however, in clinical trials, MPH did not improve treatment outcome in cocaine addiction. We hypothesized that oral MPH will attenuate ACC hypoactivations and improve associated performance during a salient cognitive task in individuals with cocaine-use disorders (CUD). In the current functional MRI study, we used a rewarded drug cue-reactivity task previously shown to be associated with hypoactivations in both major ACC subdivisions (implicated in default brain function) in CUD compared with healthy controls. The task was performed by 13 CUD and 14 matched healthy controls on 2 d: after ingesting a single dose of oral MPH (20 mg) or placebo (lactose) in a counterbalanced fashion. Results show that oral MPH increased responses to this salient cognitive task in both major ACC subdivisions (including the caudal-dorsal ACC and rostroventromedial ACC extending to the medial orbitofrontal cortex) in the CUD. These functional MRI results were associated with reduced errors of commission (a common impulsivity measure) and improved task accuracy, especially during the drug (vs. neutral) cue-reactivity condition in all subjects. The clinical application of such MPH-induced brain-behavior enhancements remains to be tested.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goldstein, R.Z.; Goldstein, R.Z.; Woicik, P.A.
Anterior cingulate cortex (ACC) hypoactivations during cognitive demand are a hallmark deficit in drug addiction. Methylphenidate (MPH) normalizes cortical function, enhancing task salience and improving associated cognitive abilities, in other frontal lobe pathologies; however, in clinical trials, MPH did not improve treatment outcome in cocaine addiction. We hypothesized that oral MPH will attenuate ACC hypoactivations and improve associated performance during a salient cognitive task in individuals with cocaine-use disorders (CUD). In the current functional MRI study, we used a rewarded drug cue-reactivity task previously shown to be associated with hypoactivations in both major ACC subdivisions (implicated in default brain function)more » in CUD compared with healthy controls. The task was performed by 13 CUD and 14 matched healthy controls on 2 d: after ingesting a single dose of oral MPH (20 mg) or placebo (lactose) in a counterbalanced fashion. Results show that oral MPH increased responses to this salient cognitive task in both major ACC subdivisions (including the caudal-dorsal ACC and rostroventromedial ACC extending to the medial orbitofrontal cortex) in the CUD. These functional MRI results were associated with reduced errors of commission (a common impulsivity measure) and improved task accuracy, especially during the drug (vs. neutral) cue-reactivity condition in all subjects. The clinical application of such MPH-induced brain-behavior enhancements remains to be tested.« less
Codner, Pablo; Malick, Waqas; Kouz, Remi; Patel, Amisha; Chen, Cheng-Han; Terre, Juan; Landes, Uri; Vahl, Torsten Peter; George, Isaac; Nazif, Tamim; Kirtane, Ajay J; Khalique, Omar K; Hahn, Rebecca T; Leon, Martin B; Kodali, Susheel
2018-05-08
Risk assessment tools currently used to predict mortality in transcatheter aortic valve implantation (TAVI) were designed for patients undergoing cardiac surgery. We aim to assess the accuracy of the TAVI dedicated American College of Cardiology / Transcatheter Valve Therapies (ACC/TVT) risk score in predicting mortality outcomes. Consecutive patients (n=1038) undergoing TAVI at a single institution from 2014 to 2016 were included. The ACC/TVT registry mortality risk score, the Society of Thoracic Surgeons - Patient Reported Outcomes (STS-PROM) score and the EuroSCORE II were calculated for all patients. In hospital and 30-day all-cause mortality rates were 1.3% and 2.9%, respectively. The ACC/TVT risk stratification tool scored higher for patients who died in-hospital than in those who survived the index hospitalization (6.4 ± 4.6 vs. 3.5 ± 1.6, p = 0.03; respectively). The ACC/TVT score showed a high level of discrimination, C-index for in-hospital mortality 0.74, 95% CI [0.59 - 0.88]. There were no significant differences between the performance of the ACC/TVT registry risk score, the EuroSCORE II and the STS-PROM for in hospital and 30-day mortality rates. The ACC/TVT registry risk model is a dedicated tool to aid in the prediction of in-hospital mortality risk after TAVI.
Fukunaga, Rena; Bogg, Tim; Finn, Peter R.; Brown, Joshua W.
2012-01-01
A sizable segment of addiction research investigates the effects of persuasive message appeals on risky and deleterious behaviors. However, to date, little research has examined how various forms of message framing and corresponding behavioral choices might by mediated by risk-related brain regions. Using event-related functional magnetic resonance imaging, we investigated brain regions hypothesized to mediate the influence of message appeals on decision making in substance-dependent (SD) compared to non-substance-dependent (non-SD) individuals. The Iowa Gambling Task (IGT) was modified to include positively-framed, negatively-framed, and control messages about long-term deck payoffs. In the positively-framed condition, the SD and non-SD groups showed improved decision-making performance that corresponded to higher risk-aversion-related brain activity in the anterior cingulate cortex (ACC) and anterior insula (AI). In contrast, in the negatively-framed condition, the SD group showed poorer performance that corresponded to lower risk-aversion-related brain activity in the AI region. In addition, only the non-SD group showed a positive association between decision quality and greater risk-related activity in the ACC, regardless of message type. The findings suggest substance-dependent individuals may have reduced neurocognitive sensitivity in the ACC and AI regions involved in risk perception and aversion during decision-making, especially in response to framed messages that emphasize reduced prospects for long-term gains. PMID:23148798
Acupuncture Modulates Resting State Connectivity in Default and Sensorimotor Brain Networks
Dhond, Rupali P.; Yeh, Calvin; Park, Kyungmo; Kettner, Norman; Napadow, Vitaly
2008-01-01
Previous studies have defined low-frequency, spatially consistent networks in resting fMRI data which may reflect functional connectivity. We sought to explore how a complex somatosensory stimulation, acupuncture, influences intrinsic connectivity in two of these networks: the default mode network (DMN) and sensorimotor network (SMN). We analyzed resting fMRI data taken before and after verum and sham acupuncture. Electrocardiography data was used to infer autonomic modulation through measures of heart rate variability (HRV). Probabilistic independent component analysis was used to separate resting fMRI data into DMN and SMN components. Following verum, but not sham, acupuncture there was increased DMN connectivity with pain (anterior cingulate cortex (ACC), periaqueductal gray), affective (amygdala, ACC), and memory (hippocampal formation, middle temporal gyrus) related brain regions. Furthermore, increased DMN connectivity with the hippocampal formation, a region known to support memory and interconnected with autonomic brain regions, was negatively correlated with acupuncture-induced increase in a sympathetic related HRV metric (LFu), and positively correlated with a parasympathetic related metric (HFu). Following verum, but not sham, acupuncture there was also increased SMN connectivity with pain related brain regions (ACC, cerebellum). We attribute differences between verum and sham acupuncture to more varied and stronger sensations evoked by verum acupuncture. Our results demonstrate for the first time that acupuncture can enhance the post-stimulation spatial extent of resting brain networks to include anti-nociceptive, memory, and affective brain regions. This modulation and sympathovagal response may relate to acupuncture analgesia and other potential therapeutic effects. PMID:18337009
Chen, Lei; Liu, Jin-cheng; Zhang, Xiao-nan; Guo, Yan-yan; Xu, Zhao-hui; Cao, Wei; Sun, Xiao-li; Sun, Wen-ji; Zhao, Ming-Gao
2008-06-01
Gentiopicroside is one of the secoiridoid compound isolated from Gentiana lutea. It exhibits analgesic activities in the mice. The anterior cingulate cortex (ACC) is a forebrain structure known for its roles in pain transmission and modulation. Painful stimuli potentiate the prefrontal synaptic transmission and induce glutamate NMDA NR2B receptor expression in the ACC. But little is known about Gentiopicroside on the persistent inflammatory pain and chronic pain-induced synaptic transmission changes in the ACC. The present study was undertaken to investigate its analgesic activities and central synaptic modulation to the peripheral painful inflammation. Gentiopicroside produced significant analgesic effects against persistent inflammatory pain stimuli in mice. Systemic administration of Gentiopicroside significantly reversed NR2B over-expression during the chronic phases of persistent inflammation caused by hind-paw administration of complete Freunds adjuvant (CFA) in mice. Whole-cell patch clamp recordings revealed that Gentiopicroside significantly reduced NR2B receptors mediated postsynaptic currents in the ACC. Our findings provide strong evidence that analgesic effects of Gentiopicroside involve down-regulation of NR2B receptors in the ACC to persistent inflammatory pain.
Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers.
Jasim Aljumaili, Saba; Rafii, M Y; Latif, M A; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous
2018-01-01
Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index ( I ) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity ( H e ) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.
Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers
Jasim Aljumaili, Saba; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous
2018-01-01
Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development. PMID:29736396
Agam, Yigal; Greenberg, Jennifer L.; Isom, Marlisa; Falkenstein, Martha J.; Jenike, Eric; Wilhelm, Sabine; Manoach, Dara S.
2014-01-01
Background Obsessive–compulsive disorder (OCD) is characterized by maladaptive repetitive behaviors that persist despite feedback. Using multimodal neuroimaging, we tested the hypothesis that this behavioral rigidity reflects impaired use of behavioral outcomes (here, errors) to adaptively adjust responses. We measured both neural responses to errors and adjustments in the subsequent trial to determine whether abnormalities correlate with symptom severity. Since error processing depends on communication between the anterior and the posterior cingulate cortex, we also examined the integrity of the cingulum bundle with diffusion tensor imaging. Methods Participants performed the same antisaccade task during functional MRI and electroencephalography sessions. We measured error-related activation of the anterior cingulate cortex (ACC) and the error-related negativity (ERN). We also examined post-error adjustments, indexed by changes in activation of the default network in trials surrounding errors. Results OCD patients showed intact error-related ACC activation and ERN, but abnormal adjustments in the post- vs. pre-error trial. Relative to controls, who responded to errors by deactivating the default network, OCD patients showed increased default network activation including in the rostral ACC (rACC). Greater rACC activation in the post-error trial correlated with more severe compulsions. Patients also showed increased fractional anisotropy (FA) in the white matter underlying rACC. Conclusions Impaired use of behavioral outcomes to adaptively adjust neural responses may contribute to symptoms in OCD. The rACC locus of abnormal adjustment and relations with symptoms suggests difficulty suppressing emotional responses to aversive, unexpected events (e.g., errors). Increased structural connectivity of this paralimbic default network region may contribute to this impairment. PMID:25057466
Middle East coastal ecosystem response to middle-to-late Holocene abrupt climate changes.
Kaniewski, D; Paulissen, E; Van Campo, E; Al-Maqdissi, M; Bretschneider, J; Van Lerberghe, K
2008-09-16
The Holocene vegetation history of the northern coastal Arabian Peninsula is of long-standing interest, as this Mediterranean/semiarid/arid region is known to be particularly sensitive to climatic changes. Detailed palynological data from an 800-cm alluvial sequence cored in the Jableh plain in northwest Syria have been used to reconstruct the vegetation dynamics in the coastal lowlands and the nearby Jabal an Nuşayriyah mountains for the period 2150 to 550 B.C. Corresponding with the 4.2 to 3.9 and 3.5 to 2.5 cal kyr BP abrupt climate changes (ACCs), two large-scale shifts to a more arid climate have been recorded. These two ACCs had different impacts on the vegetation assemblages in coastal Syria. The 3.5 to 2.5 cal kyr BP ACC is drier and lasted longer than the 4.2 to 3.9 cal kyr BP ACC, and is characterized by the development of a warm steppe pollen-derived biome (1100-800 B.C.) and a peak of hot desert pollen-derived biome at 900 B.C. The 4.2 to 3.9 cal kyr BP ACC is characterized by a xerophytic woods and shrubs pollen-derived biome ca. 2050 B.C. The impact of the 3.5 to 2.5 cal kyr BP ACC on human occupation and cultural development is important along the Syrian coast with the destruction of Ugarit and the collapse of the Ugarit kingdom at ca. 1190 to 1185 B.C.
Middle East coastal ecosystem response to middle-to-late Holocene abrupt climate changes
Kaniewski, D.; Paulissen, E.; Van Campo, E.; Al-Maqdissi, M.; Bretschneider, J.; Van Lerberghe, K.
2008-01-01
The Holocene vegetation history of the northern coastal Arabian Peninsula is of long-standing interest, as this Mediterranean/semiarid/arid region is known to be particularly sensitive to climatic changes. Detailed palynological data from an 800-cm alluvial sequence cored in the Jableh plain in northwest Syria have been used to reconstruct the vegetation dynamics in the coastal lowlands and the nearby Jabal an Nuşayriyah mountains for the period 2150 to 550 B.C. Corresponding with the 4.2 to 3.9 and 3.5 to 2.5 cal kyr BP abrupt climate changes (ACCs), two large-scale shifts to a more arid climate have been recorded. These two ACCs had different impacts on the vegetation assemblages in coastal Syria. The 3.5 to 2.5 cal kyr BP ACC is drier and lasted longer than the 4.2 to 3.9 cal kyr BP ACC, and is characterized by the development of a warm steppe pollen-derived biome (1100–800 B.C.) and a peak of hot desert pollen-derived biome at 900 B.C. The 4.2 to 3.9 cal kyr BP ACC is characterized by a xerophytic woods and shrubs pollen-derived biome ca. 2050 B.C. The impact of the 3.5 to 2.5 cal kyr BP ACC on human occupation and cultural development is important along the Syrian coast with the destruction of Ugarit and the collapse of the Ugarit kingdom at ca. 1190 to 1185 B.C. PMID:18772385
Uddin, Monica; Wildman, Derek E.; Liu, Guozhen; Xu, Wenbo; Johnson, Robert M.; Hof, Patrick R.; Kapatos, Gregory; Grossman, Lawrence I.; Goodman, Morris
2004-01-01
Gene expression profiles from the anterior cingulate cortex (ACC) of human, chimpanzee, gorilla, and macaque samples provide clues about genetic regulatory changes in human and other catarrhine primate brains. The ACC, a cerebral neocortical region, has human-specific histological features. Physiologically, an individual's ACC displays increased activity during that individual's performance of cognitive tasks. Of ≈45,000 probe sets on microarray chips representing transcripts of all or most human genes, ≈16,000 were commonly detected in human ACC samples and comparable numbers, 14,000–15,000, in gorilla and chimpanzee ACC samples. Phylogenetic results obtained from gene expression profiles contradict the traditional expectation that the non-human African apes (i.e., chimpanzee and gorilla) should be more like each other than either should be like humans. Instead, the chimpanzee ACC profiles are more like the human than like the gorilla; these profiles demonstrate that chimpanzees are the sister group of humans. Moreover, for those unambiguous expression changes mapping to important biological processes and molecular functions that statistically are significantly represented in the data, the chimpanzee clade shows at least as much apparent regulatory evolution as does the human clade. Among important changes in the ancestry of both humans and chimpanzees, but to a greater extent in humans, are the up-regulated expression profiles of aerobic energy metabolism genes and neuronal function-related genes, suggesting that increased neuronal activity required increased supplies of energy. PMID:14976249
Early emergence of anthropogenically forced heat waves in the western United States and Great Lakes
NASA Astrophysics Data System (ADS)
Lopez, Hosmay; West, Robert; Dong, Shenfu; Goni, Gustavo; Kirtman, Ben; Lee, Sang-Ki; Atlas, Robert
2018-05-01
Climate projections for the twenty-first century suggest an increase in the occurrence of heat waves. However, the time at which externally forced signals of anthropogenic climate change (ACC) emerge against background natural variability (time of emergence (ToE)) has been challenging to quantify, which makes future heat-wave projections uncertain. Here we combine observations and model simulations under present and future forcing to assess how internal variability and ACC modulate US heat waves. We show that ACC dominates heat-wave occurrence over the western United States and Great Lakes regions, with ToE that occurred as early as the 2020s and 2030s, respectively. In contrast, internal variability governs heat waves in the northern and southern Great Plains, where ToE occurs in the 2050s and 2070s; this later ToE is believed to be a result of a projected increase in circulation variability, namely the Great Plain low-level jet. Thus, greater mitigation and adaptation efforts are needed in the Great Lakes and western United States regions.
Khalsa, Sahib S.; Damasio, Antonio; Tranel, Daniel; Landini, Gregory; Williford, Kenneth
2012-01-01
It has been proposed that self-awareness (SA), a multifaceted phenomenon central to human consciousness, depends critically on specific brain regions, namely the insular cortex, the anterior cingulate cortex (ACC), and the medial prefrontal cortex (mPFC). Such a proposal predicts that damage to these regions should disrupt or even abolish SA. We tested this prediction in a rare neurological patient with extensive bilateral brain damage encompassing the insula, ACC, mPFC, and the medial temporal lobes. In spite of severe amnesia, which partially affected his “autobiographical self”, the patient's SA remained fundamentally intact. His Core SA, including basic self-recognition and sense of self-agency, was preserved. His Extended SA and Introspective SA were also largely intact, as he has a stable self-concept and intact higher-order metacognitive abilities. The results suggest that the insular cortex, ACC and mPFC are not required for most aspects of SA. Our findings are compatible with the hypothesis that SA is likely to emerge from more distributed interactions among brain networks including those in the brainstem, thalamus, and posteromedial cortices. PMID:22927899
Fitzgerald, Daniel A.; Piejko, Katherine; Roberts, Julia; Kennedy, Amy E.; Phan, K. Luan
2016-01-01
Generalized social anxiety disorder (gSAD) is associated with aberrant anterior cingulate cortex (ACC) response to threat distractors. Perceptual load has been shown to modulate ACC activity such that under high load, when demands on processing capacity is restricted, individuals with gSAD exhibit compensatory activation to threat distractors yet under low load, there is evidence of reduced activation. It is not known if neural predictors of response to cognitive behavioral therapy (CBT), based on such emotional conflict resolution, interact with demands on controlled processes. Prior to CBT, 32 patients with gSAD completed an fMRI task involving a target letter in a string of identical targets (low perceptual load) or a target letter in a mixed letter string (high perceptual load) superimposed on fearful, angry and neutral face distractors. Whole-brain voxel-wise analyses revealed better CBT outcome was predicted by more frontopartial activity that included dorsal ACC (dACC) and insula to threat (vs neutral) distractors during high, but not low, perceptual load. Psychophysiological interaction analysis with dACC as the seed region revealed less connectivity with dorsolateral prefrontal cortex to threat distractors during high load. Results indicate patients with less regulatory capability when demands on higher-order control are great may benefit more from CBT. PMID:26634281
Social reinforcement can regulate localized brain activity.
Mathiak, Krystyna A; Koush, Yury; Dyck, Miriam; Gaber, Tilman J; Alawi, Eliza; Zepf, Florian D; Zvyagintsev, Mikhail; Mathiak, Klaus
2010-11-01
Social learning is essential for adaptive behavior in humans. Neurofeedback based on functional magnetic resonance imaging (fMRI) trains control over localized brain activity. It can disentangle learning processes at the neural level and thus investigate the mechanisms of operant conditioning with explicit social reinforcers. In a pilot study, a computer-generated face provided a positive feedback (smiling) when activity in the anterior cingulate cortex (ACC) increased and gradually returned to a neutral expression when the activity dropped. One female volunteer without previous experience in fMRI underwent training based on a social reinforcer. Directly before and after the neurofeedback runs, neural responses to a cognitive interference task (Simon task) were recorded. We observed a significant increase in activity within ACC during the neurofeedback blocks, correspondent with the a-priori defined anatomical region of interest. In the course of the neurofeedback training, the subject learned to regulate ACC activity and could maintain the control even without direct feedback. Moreover, ACC was activated significantly stronger during Simon task after the neurofeedback training when compared to before. Localized brain activity can be controlled by social reward. The increased ACC activity transferred to a cognitive task with the potential to reduce cognitive interference. Systematic studies are required to explore long-term effects on social behavior and clinical applications.
Is axillary surgery beneficial for patients with adenoid cystic carcinoma of the breast?
Welsh, Jessemae L; Keeney, Michael G; Hoskin, Tanya L; Glazebrook, Katrina N; Boughey, Judy C; Shah, Sejal S; Hieken, Tina J
2017-11-01
Adenoid cystic carcinoma (ACC) is a rare, typically triple-negative, breast cancer reported to have a favorable prognosis and low rate of nodal metastasis. No consensus guidelines exist for axillary staging and treatment. We identified all patients with ACC evaluated at our institution from January 1994 to August 2016. Patient, tumor, and treatment variables were abstracted and analyzed. We identified 20 pure ACCs (0.13% of all invasive breast cancers) with size range 0.2-4.8 cm, in 19 women, median age 59 years. Preoperative axillary ultrasound was normal in 10/13 women and suspicious in 3/13 who had a subsequent negative lymph node fine needle aspiration (FNA). Fifteen patients (75%) had sentinel lymph node surgery and were pathologically node-negative, while the remaining five had no axillary surgery. With 3.6 years median follow-up (range 0.2-38.6 years), three patients experienced an in-breast recurrence at 2, 16, and 17 years, respectively, while none recurred in regional nodes. We observed no cases of nodal metastasis in 20 consecutive cases of ACC of the breast. Preoperative axillary ultrasound with FNA of suspicious nodes accurately predicted pathologic nodal stage. These data suggest axillary surgery might be omitted safely in patients with pure ACC and a clinically negative axilla. © 2017 Wiley Periodicals, Inc.
The role of the anterior cingulate cortex in the affective evaluation of conflict
Braem, Senne; King, Joseph A.; Korb, Franziska M.; Krebs, Ruth M.; Notebaert, Wim; Egner, Tobias
2017-01-01
An influential theory of anterior cingulate cortex (ACC) function argues that this brain region plays a crucial role in the affective evaluation of performance monitoring and control demands. Specifically, control-demanding processes such as response conflict, are thought to be registered as aversive signals by the ACC, which in turn triggers processing adjustments to support avoidance-learning. In support of conflict being treated as an aversive event, recent behavioural studies demonstrated that incongruent (i.e., conflict-inducing) relative to congruent stimuli can speed up subsequent negative relative to positive affective picture processing. Here, we used functional magnetic resonance imaging (fMRI) to investigate directly whether ACC activity in response to negative versus positive pictures is modulated by preceding control demands, consisting of conflict and task-switching conditions. The results show that negative relative to positive pictures elicited higher ACC activation following congruent relative to incongruent trials, suggesting that the ACC’s response to negative (positive) pictures was indeed affectively primed by incongruent (congruent) trials. Interestingly, this pattern of results was observed on task repetitions, but disappeared on task alternations. Our findings support the proposal that conflict induces negative affect, and are the first to show that this affective signal is reflected in ACC activation. PMID:27575278
Palomero-Gallagher, Nicola; Eickhoff, Simon B; Hoffstaedter, Felix; Schleicher, Axel; Mohlberg, Hartmut; Vogt, Brent A; Amunts, Katrin; Zilles, Karl
2015-07-15
Human subgenual anterior cingulate cortex (sACC) is involved in affective experiences and fear processing. Functional neuroimaging studies view it as a homogeneous cortical entity. However, sACC comprises several distinct cyto- and receptorarchitectonical areas: 25, s24, s32, and the ventral portion of area 33. Thus, we hypothesized that the areas may also be connectionally and functionally distinct. We performed structural post mortem and functional in vivo analyses. We computed probabilistic maps of each area based on cytoarchitectonical analysis of ten post mortem brains. Maps, publicly available via the JuBrain atlas and the Anatomy Toolbox, were used to define seed regions of task-dependent functional connectivity profiles and quantitative functional decoding. sACC areas presented distinct co-activation patterns within widespread networks encompassing cortical and subcortical regions. They shared common functional domains related to emotion, perception and cognition. A more specific analysis of these domains revealed an association of s24 with sadness, and of s32 with fear processing. Both areas were activated during taste evaluation, and co-activated with the amygdala, a key node of the affective network. s32 co-activated with areas of the executive control network, and was associated with tasks probing cognition in which stimuli did not have an emotional component. Area 33 was activated by painful stimuli, and co-activated with areas of the sensorimotor network. These results support the concept of a connectional and functional specificity of the cyto- and receptorarchitectonically defined areas within the sACC, which can no longer be seen as a structurally and functionally homogeneous brain region. Copyright © 2015 Elsevier Inc. All rights reserved.
Clausen, Ashley N.; Billinger, Sandra A.; Sisante, Jason-Flor V.; Suzuki, Hideo; Aupperle, Robin L.
2017-01-01
Background: Combat-exposed veteran populations are at an increased risk for developing cardiovascular disease. The anterior cingulate cortex (ACC) and insula have been implicated in both autonomic arousal to emotional stressors and homeostatic processes, which may contribute to cardiovascular dysfunction in combat veteran populations. The aim of the present study was to explore the intersecting relationships of combat experiences, rostral ACC and posterior insula volume, and cardiovascular health in a sample of combat veterans. Method: Twenty-four male combat veterans completed clinical assessment of combat experiences and posttraumatic stress symptoms. Subjects completed a magnetic resonance imaging scan and autosegmentation using FreeSurfer was used to estimate regional gray matter volume (controlling for total gray matter volume) of the rostral ACC and posterior insula. Flow-mediated dilation (FMD) was conducted to assess cardiovascular health. Theil-sen robust regressions and Welch's analysis of variance were used to examine relationships of combat experiences and PTSD symptomology with (1) FMD and (2) regional gray matter volume. Results: Increased combat experiences, deployment duration, and multiple deployments were related to smaller posterior insula volume. Combat experiences were marginally associated with poorer cardiovascular health. However, cardiovascular health was not related to rostral ACC or posterior insula volume. Conclusion: The present study provides initial evidence for the relationships of combat experiences, deployment duration, and multiple deployments with smaller posterior insula volume. Results may suggest that veterans with increased combat experiences may exhibit more dysfunction regulating the autonomic nervous system, a key function of the posterior insula. However, the relationship between combat and cardiovascular health was not mediated by regional brain volume. Future research is warranted to further clarify the cardiovascular or functional impact of smaller posterior insula volume in combat veterans. PMID:29312038
Mohseni, Hamid R.; Smith, Penny P.; Parsons, Christine E.; Young, Katherine S.; Hyam, Jonathan A.; Stein, Alan; Stein, John F.; Green, Alexander L.; Aziz, Tipu Z.; Kringelbach, Morten L.
2012-01-01
Deep brain stimulation (DBS) has been shown to be clinically effective for some forms of treatment-resistant chronic pain, but the precise mechanisms of action are not well understood. Here, we present an analysis of magnetoencephalography (MEG) data from a patient with whole-body chronic pain, in order to investigate changes in neural activity induced by DBS for pain relief over both short- and long-term. This patient is one of the few cases treated using DBS of the anterior cingulate cortex (ACC). We demonstrate that a novel method, null-beamforming, can be used to localise accurately brain activity despite the artefacts caused by the presence of DBS electrodes and stimulus pulses. The accuracy of our source localisation was verified by correlating the predicted DBS electrode positions with their actual positions. Using this beamforming method, we examined changes in whole-brain activity comparing pain relief achieved with deep brain stimulation (DBS ON) and compared with pain experienced with no stimulation (DBS OFF). We found significant changes in activity in pain-related regions including the pre-supplementary motor area, brainstem (periaqueductal gray) and dissociable parts of caudal and rostral ACC. In particular, when the patient reported experiencing pain, there was increased activity in different regions of ACC compared to when he experienced pain relief. We were also able to demonstrate long-term functional brain changes as a result of continuous DBS over one year, leading to specific changes in the activity in dissociable regions of caudal and rostral ACC. These results broaden our understanding of the underlying mechanisms of DBS in the human brain. PMID:22675503
Silvestrini, Nicolas
2017-09-01
Numerous studies have assessed cardiovascular (CV) reactivity as a measure of effort mobilization during cognitive tasks. However, psychological and neural processes underlying effort-related CV reactivity are still relatively unclear. Previous research reliably found that CV reactivity during cognitive tasks is mainly determined by one region of the brain, the dorsal anterior cingulate cortex (dACC), and that this region is systematically engaged during cognitively demanding tasks. The present integrative approach builds on the research on cognitive control and its brain correlates that shows that dACC function can be related to conflict monitoring and integration of information related to task difficulty and success importance-two key variables in determining effort mobilization. In contrast, evidence also indicates that executive cognitive functioning is processed in more lateral regions of the prefrontal cortex. The resulting model suggests that, when automatic cognitive processes are insufficient to sustain behavior, the dACC determines the amount of required and justified effort according to task difficulty and success importance, which leads to proportional adjustments in CV reactivity and executive cognitive functioning. These propositions are discussed in relation to previous findings on effort-related CV reactivity and cognitive performance, new predictions for future studies, and relevance for other self-regulatory processes. Copyright © 2016 Elsevier B.V. All rights reserved.
Altered resting-state amygdala functional connectivity in men with posttraumatic stress disorder
Sripada, Rebecca K.; King, Anthony P.; Garfinkel, Sarah N.; Wang, Xin; Sripada, Chandra S.; Welsh, Robert C.; Liberzon, Israel
2012-01-01
Background Converging neuroimaging research suggests altered emotion neurocircuitry in individuals with posttraumatic stress disorder (PTSD). Emotion activation studies in these individuals have shown hyperactivation in emotion-related regions, including the amygdala and insula, and hypoactivation in emotion-regulation regions, including the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). However, few studies have examined patterns of connectivity at rest in individuals with PTSD, a potentially powerful method for illuminating brain network structure. Methods Using the amygdala as a seed region, we measured resting-state brain connectivity using 3 T functional magnetic resonance imaging in returning male veterans with PTSD and combat controls without PTSD. Results Fifteen veterans with PTSD and 14 combat controls enrolled in our study. Compared with controls, veterans with PTSD showed greater positive connectivity between the amygdala and insula, reduced positive connectivity between the amygdala and hippocampus, and reduced anticorrelation between the amygdala and dorsal ACC and rostral ACC. Limitations Only male veterans with combat exposure were tested, thus our findings cannot be generalized to women or to individuals with non–combat related PTSD. Conclusion These results demonstrate that studies of functional connectivity during resting state can discern aberrant patterns of coupling within emotion circuits and suggest a possible brain basis for emotion-processing and emotion-regulation deficits in individuals with PTSD. PMID:22313617
The neural basis of monitoring goal progress
Benn, Yael; Webb, Thomas L.; Chang, Betty P. I.; Sun, Yu-Hsuan; Wilkinson, Iain D.; Farrow, Tom F. D.
2014-01-01
The neural basis of progress monitoring has received relatively little attention compared to other sub-processes that are involved in goal directed behavior such as motor control and response inhibition. Studies of error-monitoring have identified the dorsal anterior cingulate cortex (dACC) as a structure that is sensitive to conflict detection, and triggers corrective action. However, monitoring goal progress involves monitoring correct as well as erroneous events over a period of time. In the present research, 20 healthy participants underwent functional magnetic resonance imagining (fMRI) while playing a game that involved monitoring progress toward either a numerical or a visuo-spatial target. The findings confirmed the role of the dACC in detecting situations in which the current state may conflict with the desired state, but also revealed activations in the frontal and parietal regions, pointing to the involvement of processes such as attention and working memory (WM) in monitoring progress over time. In addition, activation of the cuneus was associated with monitoring progress toward a specific target presented in the visual modality. This is the first time that activation in this region has been linked to higher-order processing of goal-relevant information, rather than low-level anticipation of visual stimuli. Taken together, these findings identify the neural substrates involved in monitoring progress over time, and how these extend beyond activations observed in conflict and error monitoring. PMID:25309380
Huang, Anna S.; Klein, Daniel N.; Leung, Hoi-Chung
2015-01-01
Spatial working memory is a central cognitive process that matures through adolescence in conjunction with major changes in brain function and anatomy. Here we focused on late childhood and early adolescence to more closely examine the neural correlates of performance variability during this important transition period. Using a modified spatial 1-back task with two memory load conditions in an fMRI study, we examined the relationship between load-dependent neural responses and task performance in a sample of 39 youth aged 9–12 years. Our data revealed that between-subject differences in task performance was predicted by load-dependent deactivation in default network regions, including the ventral anterior cingulate cortex (vACC) and posterior cingulate cortex (PCC). Although load-dependent increases in activation in prefrontal and posterior parietal regions were only weakly correlated with performance, increased prefrontal-parietal coupling was associated with better performance. Furthermore, behavioral measures of executive function from as early as age 3 predicted current load-dependent deactivation in vACC and PCC. These findings suggest that both task positive and task negative brain activation during spatial working memory contributed to successful task performance in late childhood/early adolescence. This may serve as a good model for studying executive control deficits in developmental disorders. PMID:26562059
The neural basis of stereotypic impact on multiple social categorization.
Hehman, Eric; Ingbretsen, Zachary A; Freeman, Jonathan B
2014-11-01
Perceivers extract multiple social dimensions from another's face (e.g., race, emotion), and these dimensions can become linked due to stereotypes (e.g., Black individuals → angry). The current research examined the neural basis of detecting and resolving conflicts between top-down stereotypes and bottom-up visual information in person perception. Participants viewed faces congruent and incongruent with stereotypes, via variations in race and emotion, while neural activity was measured using fMRI. Hand movements en route to race/emotion responses were recorded using mouse-tracking to behaviorally index individual differences in stereotypical associations during categorization. The medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC) showed stronger activation to faces that violated stereotypical expectancies at the intersection of multiple social categories (i.e., race and emotion). These regions were highly sensitive to the degree of incongruency, exhibiting linearly increasing responses as race and emotion became stereotypically more incongruent. Further, the ACC exhibited greater functional connectivity with the lateral fusiform cortex, a region implicated in face processing, when viewing stereotypically incongruent (relative to congruent) targets. Finally, participants with stronger behavioral tendencies to link race and emotion stereotypically during categorization showed greater dorsolateral prefrontal cortex activation to stereotypically incongruent targets. Together, the findings provide insight into how conflicting stereotypes at the nexus of multiple social dimensions are resolved at the neural level to accurately perceive other people. Copyright © 2014 Elsevier Inc. All rights reserved.
Huang, Anna S; Klein, Daniel N; Leung, Hoi-Chung
2016-02-01
Spatial working memory is a central cognitive process that matures through adolescence in conjunction with major changes in brain function and anatomy. Here we focused on late childhood and early adolescence to more closely examine the neural correlates of performance variability during this important transition period. Using a modified spatial 1-back task with two memory load conditions in an fMRI study, we examined the relationship between load-dependent neural responses and task performance in a sample of 39 youth aged 9-12 years. Our data revealed that between-subject differences in task performance was predicted by load-dependent deactivation in default network regions, including the ventral anterior cingulate cortex (vACC) and posterior cingulate cortex (PCC). Although load-dependent increases in activation in prefrontal and posterior parietal regions were only weakly correlated with performance, increased prefrontal-parietal coupling was associated with better performance. Furthermore, behavioral measures of executive function from as early as age 3 predicted current load-dependent deactivation in vACC and PCC. These findings suggest that both task positive and task negative brain activation during spatial working memory contributed to successful task performance in late childhood/early adolescence. This may serve as a good model for studying executive control deficits in developmental disorders. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Ronchi, Cristina L; Kroiss, Matthias; Sbiera, Silviu; Deutschbein, Timo; Fassnacht, Martin
2014-07-01
Adrenocortical carcinoma (ACC) is not only a rare and heterogeneous disease but also one of the most aggressive endocrine tumors. Despite significant advances in the last decade, its pathogenesis is still only incompletely understood and overall therapeutic means are unsatisfactory. Herein, we provide our personal view of the currently available treatment options and suggest the following research efforts that we consider timely and necessary to improve therapy: i) for better outcome in localized ACCs, surgery should be restricted to experienced centers, which should then collaborate closely to address the key surgical questions (e.g. best approach and extent of surgery) in a multicenter manner. ii) For the development of better systemic therapies, it is crucial to elucidate the exact molecular mechanisms of action of mitotane. iii) A prospective trial is needed to address the role of cytotoxic drugs in the adjuvant setting in aggressive ACCs (e.g. mitotane vs mitotane+cisplatin). iv) For metastatic ACCs, new regimens should be investigated as first-line therapy. v) Several other issues (e.g. the role of radiotherapy and salvage therapies) might be answered - at least in a first step - by large retrospective multicenter studies. In conclusion, although it is unrealistic to expect that the majority of ACCs can be cured within the next decade, international collaborative efforts (including multiple translational and clinical studies) should allow significant improvement of clinical outcome of this disease. To this end, it might be reasonable to expand the European Network for the Study of Adrenal Tumors (ENSAT) to a truly worldwide international network - INSAT. © 2014 European Society of Endocrinology.
A feasibility study on porting the community land model onto accelerators using OpenACC
Wang, Dali; Wu, Wei; Winkler, Frank; ...
2014-01-01
As environmental models (such as Accelerated Climate Model for Energy (ACME), Parallel Reactive Flow and Transport Model (PFLOTRAN), Arctic Terrestrial Simulator (ATS), etc.) became more and more complicated, we are facing enormous challenges regarding to porting those applications onto hybrid computing architecture. OpenACC appears as a very promising technology, therefore, we have conducted a feasibility analysis on porting the Community Land Model (CLM), a terrestrial ecosystem model within the Community Earth System Models (CESM)). Specifically, we used automatic function testing platform to extract a small computing kernel out of CLM, then we apply this kernel into the actually CLM dataflowmore » procedure, and investigate the strategy of data parallelization and the benefit of data movement provided by current implementation of OpenACC. Even it is a non-intensive kernel, on a single 16-core computing node, the performance (based on the actual computation time using one GPU) of OpenACC implementation is 2.3 time faster than that of OpenMP implementation using single OpenMP thread, but it is 2.8 times slower than the performance of OpenMP implementation using 16 threads. On multiple nodes, MPI_OpenACC implementation demonstrated very good scalability on up to 128 GPUs on 128 computing nodes. This study also provides useful information for us to look into the potential benefits of “deep copy” capability and “routine” feature of OpenACC standards. In conclusion, we believe that our experience on the environmental model, CLM, can be beneficial to many other scientific research programs who are interested to porting their large scale scientific code using OpenACC onto high-end computers, empowered by hybrid computing architecture.« less
Alame, Aya J; Karatasakis, Aris; Karacsonyi, Judit; Danek, Barbara A; Resendes, Erica; Martinez Parachini, Jose R; Kalsaria, Pratik; Roesle, Michele; Rangan, Bavana V; Sorajja, Paul; Jneid, Hani; Banerjee, Subhash; Brilakis, Emmanouil S
2017-06-01
The American College of Cardiology (ACC), the American Heart Association (AHA), and the European Society of Cardiology (ESC) have been developing guidelines to assist clinicians in making evidence-based decisions. The current ACC/AHA and ESC guidelines for non-ST-segment elevation acute coronary syndromes (NSTE-ACS) that were updated in 2014 and 2015, respectively, were compared to assess the number of recommendations on the basis of class of recommendation and level of evidence (LOE), the sources cited, and the content. The total number of recommendations in the ACC/AHA and ESC guidelines was 182 and 147, respectively. The recommendation class distribution of the ACC/AHA guidelines was 61.0% class I (compared with 61.9% in the ESC guidelines, P=0.865), 29.7% class II (compared with 32.0% in the ESC guidelines, P=0.653), and 9.3% class III (compared with 6.1% in the ESC guidelines, P=0.282). The LOE distribution among ACC/AHA guidelines was 15.9% LOE A (compared with 27.9% in the ESC guidelines, P=0.008), 50.0% LOE B (compared with 33.3% in the ESC guidelines, P=0.002), and 34.1% LOE C (compared with 38.8% in the ESC guidelines, P=0.377). The ACC/AHA guidelines cited 827 publications and the ESC guidelines cited 551 publications, 124 of which were shared by both sets of guidelines. The guidelines' approaches to NSTE-ACS were consistent, with minor differences in diagnostic and medical therapy recommendations. Overall, the ACC/AHA and ESC guidelines contain a comparable number of recommendations and provide similar guidance for the management of patients with NSTE-ACS.
Hulka, Lea M; Scheidegger, Milan; Vonmoos, Matthias; Preller, Katrin H; Baumgartner, Markus R; Herdener, Marcus; Seifritz, Erich; Henning, Anke; Quednow, Boris B
2016-01-01
Cocaine addiction is a chronically relapsing disorder that is associated with harmful consequences. Relapses occur frequently and effective pharmacotherapies are currently sparse. Preclinical studies suggest that altered glutamatergic signaling is crucial for the maintenance of cocaine self-administration. However, the translational validity of these models is currently unknown. Therefore, we investigated potential differences of glutamate, glutamine and further metabolite levels in the pregenual anterior cingulate cortex (pgACC) and the right dorsolateral prefrontal cortex (rDLPFC) of chronic cocaine users and controls using the PRior knOwledge FITting 2.0 tool in combination with two-dimensional J-resolved single-voxel (1) H-magnetic resonance spectroscopy at 3T and voxel tissue composition and relaxation correction. Glutamate and glutamine levels did not differ between cocaine users and controls, but higher weekly cocaine use and higher cocaine hair concentrations were associated with lower glutamine/creatine ratios in the pgACC. Interestingly, cocaine users exhibited higher glucose/total creatine ratios than controls in the pgACC and higher choline/creatine ratios in the pgACC and rDLPFC. These results imply that cocaine use is associated with altered cortical glucose metabolism and membrane turnover. Finally, cocaine use over the past 6 months appears to decrease cortical glutamine levels indicating changes in glutamate cycling. © 2014 Society for the Study of Addiction.
Straub, J; Metzger, C D; Plener, P L; Koelch, M G; Groen, G; Abler, B
2017-02-01
Current resting state imaging findings support suggestions that the neural signature of depression and therefore also its therapy should be conceptualized as a network disorder rather than a dysfunction of specific brain regions. In this study, we compared neural connectivity of adolescent patients with depression (PAT) and matched healthy controls (HC) and analysed pre-to-post changes of seed-based network connectivities in PAT after participation in a cognitive behavioral group psychotherapy (CBT). 38 adolescents (30 female; 19 patients; 13-18 years) underwent an eyes-closed resting-state scan. PAT were scanned before (pre) and after (post) five sessions of CBT. Resting-state functional connectivity was analysed in a seed-based approach for right-sided amygdala and subgenual anterior cingulate cortex (sgACC). Symptom severity was assessed using the Beck Depression Inventory Revision (BDI-II). Prior to group CBT, between groups amygdala and sgACC connectivity with regions of the default mode network was stronger in the patients group relative to controls. Within the PAT group, a similar pattern significantly decreased after successful CBT. Conversely, seed-based connectivity with affective regions and regions processing cognition and salient stimuli was stronger in HC relative to PAT before CBT. Within the PAT group, a similar pattern changed with CBT. Changes in connectivity correlated with the significant pre-to-post symptom improvement, and pre-treatment amygdala connectivity predicted treatment response in depressed adolescents. Sample size and missing long-term follow-up limit the interpretability. Successful group psychotherapy of depression in adolescents involved connectivity changes in resting state networks to that of healthy controls. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Measures, C. I.; Brown, M. T.; Selph, K. E.; Apprill, A.; Zhou, M.; Hatta, M.; Hiscock, W. T.
2013-06-01
Dissolved trace element distributions near Elephant Island in the Drake Passage show extremely high levels of dissolved Fe and Mn in waters above the shelf. The entrainment of this enriched shelf water by the Fe-poor Antarctic Circumpolar Current (ACC) as it passes through the Shackleton Gap delivers an estimated 2.8×106 mol yr-1 dissolved Fe to the offshore waters of the Drake Passage. The magnitude and spatial distribution of dissolved Fe, Mn and Al over the shelf are consistent with a diagenetically produced sedimentary source, but are inconsistent with eolian or upwelling sources. The systematics of the Mn and Fe concentrations suggest that there are two distinct sources of dissolved Fe to the surface waters of this region. The highest Fe concentrations are associated with Bransfield Strait water, which can be identified by its characteristic temperature and salinity (T/S) properties both inside the Bransfield Strait and in the Bransfield Current outflow between Elephant and Clarence Islands. Most of the shelf area is dominated by a second water type with T/S properties that are typical of modified Antarctic Surface Water, which while also enriched has a lower Fe:Mn ratio. The predominantly linear relationships between the Fe and Mn concentrations at the stations in each of these water mass types suggest that the distribution of these elements is largely controlled by physical mixing processes and that biological removal of Fe on the shelf, while certainly occurring, is limited, perhaps as a result of rapid physical flushing processes and relatively slow biological growth rates. The consequent export of large quantities of this shelf-derived Fe into the ACC is likely responsible for the extensive regions of enhanced primary production seen in satellite imagery downstream of the Drake Passage.
NASA Astrophysics Data System (ADS)
LI, Q.; Lee, S.
2016-12-01
The relationship between Antarctic Circumpolar Current (ACC) jets and eddy fluxes in the Indo-western Pacific Southern Ocean (90°E-145°E) is investigated using an eddy-resolving model. In this region, transient eddy momentum flux convergence occurs at the latitude of the primary jet core, whereas eddy buoyancy flux is located over a broader region that encompasses the jet and the inter-jet minimum. In a small sector (120°E-144°E) where jets are especially zonal, a spatial and temporal decomposition of the eddy fluxes further reveals that fast eddies act to accelerate the jet with the maximum eddy momentum flux convergence at the jet center, while slow eddies tend to decelerate the zonal current at the inter-jet minimum. Transformed Eulerian mean (TEM) diagnostics reveals that the eddy momentum contribution accelerates the jets at all model depths, whereas the buoyancy flux contribution decelerates the jets at depths below 600 m. In ocean sectors where the jets are relatively well defined, there exist jet-scale overturning circulations (JSOC) with sinking motion on the equatorward flank, and rising motion on the poleward flank of the jets. The location and structure of these thermally indirect circulations suggest that they are driven by the eddy momentum flux convergence, much like the Ferrel cell in the atmosphere. This study also found that the JSOC plays a significant role in the oceanic heat transport and that it also contributes to the formation of a thin band of mixed layer that exists on the equatorward flank of the Indo-western Pacific ACC jets.
Development of Ultra-Low Platinum Alloy Cathode Catalysts for PEM Fuel Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Popov, Branko N.; Weidner, John
2016-01-07
The goal of this project is to synthesize a low cost PEM fuel cell cathode catalyst and support with optimized average mass activity, stability of mass activity, initial high current density performance under H 2/air (power density), and catalyst and support stability able to meet 2017 DOE targets for electrocatalysts for transportation applications. Pt*/ACCS-2 catalyst was synthesized according to a novel methodology developed at USC through: (i) surface modification, (ii) metal catalyzed pyrolysis and (iii) chemical leaching to remove excess meal used to dope the support. Pt* stands for suppressed platinum catalyst synthesized with Co doped platinum. The procedure resultsmore » in increasing carbon graphitization, inclusion of cobalt in the bulk and formation of non-metallic active sites on the carbon surface. Catalytic activity of the support shows an onset potential of 0.86 V for the oxygen reduction reaction (ORR) with well-defined kinetic and mass transfer regions and 2.5% H 2O 2 production. Pt*/ACCS-2 catalyst durability under 0.6-1.0 V potential cycling and support stability under 1.0-1.5 V potential cycling was evaluated. The results indicated excellent catalyst and support performance under simulated start-up/shut down operating conditions (1.0 – 1.5 V, 5000 cycles) which satisfy DOE 2017 catalyst and support durability and activity. The 30% Pt*/ACCS-2 catalyst showed high initial mass activity of 0.34 A/mg PGM at 0.9 ViR-free and loss of mass activity of 45% after 30,000 cycles (0.6-1.0 V). The catalyst performance under H 2-air fuel cell operating conditions showed only 24 mV (iR-free) loss at 0.8 A/cm 2 with an ECSA loss of 42% after 30,000 cycles (0.6-1.0 V). The support stability under 1.0-1.5 V potential cycling showed mass activity loss of 50% and potential loss of 8 mV (iR-free) at 1.5 A/cm 2. The ECSA loss was 22% after 5,000 cycles. Furthermore, the Pt*/ACCS-2 catalyst showed an initial power density (rated) of 0.174 g PGM/kW. Excellent activity and stability of the catalyst are due to synergistic effect of the catalytic activity and stability of ACCS-2, its enhanced hydrophobicity as well as activity of compressive Pt* lattice catalysts. For the first time, we report a carbon based support which is stable under simulated start-up/shut down operating conditions. Five 25cm 2 MEA’s were fabricated at USC using Pt*/ACCS-2 cathode catalyst for independent evaluation at National Renewable Energy. In the Final NREL report they summarize their results as follow: (1) Initial ORR activity and performance of the USC MEA’s Pt*/ACCS-2 under oxygen air, evaluated at NREL were comparable to that measured and reported by USC in their report: (2) Cyclic durability studies indicate that Pt*/ACCS-2 catalysts has minimal losses in activity and performant under 1-1.5 V potential cycling indicating a robust corrosion resistant support.« less
Active geologic processes in Barrow Canyon, northeast Chukchi Sea
Eittreim, S.; Grantz, A.; Greenberg, J.
1982-01-01
Circulation patterns on the shelf and at the shelf break appear to dominate the Barrow Canyon system. The canyon's shelf portion underlies and is maintained by the Alaska Coastal Current (A.C.C.), which flows northeastward along the coast toward the northeast corner of the broad Chukchi Sea. Offshelf and onshelf advective processes are indicated by oceanographic measurements of other workers. These advective processes may play an important role in the production of bedforms that are found near the canyon head as well as in processes of erosion or non-deposition in the deeper canyon itself. Coarse sediments recovered from the canyon axis at 400 to 570 m indicate that there is presently significant flow along the canyon. The canyon hooks left at a point north of Point Barrow where the A.C.C. loses its coastal constriction. The left hook, as well as preferential west-wall erosion, continues down to the abyssal plain of the Canada Basin at 3800 m. A possible explanation for the preferential west-wall erosion along the canyon, at least for the upper few hundred meters, is that the occasional upwelling events, which cause nutrient-rich water to flow along the west wall would in turn cause larger populations of burrowing organisms to live there than on the east wall, and that these organisms cause high rates of bioerosion. This hypothesis assumes that the dominant factor in the canyon's erosion is biological activity, not current velocity. Sedimentary bedforms consisting of waves and furrows are formed in soft mud in a region on the shelf west of the canyon head; their presence there perhaps reflects: (a) the supply of fine suspended sediments delivered by the A.C.C. from sources to the south, probably the Yukon and other rivers draining northwestern Alaska; and (b) the westward transport of these suspended sediments by the prevailing Beaufort Gyre which flows along the outer shelf. ?? 1982.
Sato, T; Oeller, P W; Theologis, A
1991-02-25
The key regulatory enzyme in the biosynthetic pathway of the plant hormone ethylene is 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (EC 4.4.1.14). We have partially purified ACC synthase 6,000-fold from Cucurbita fruit tissue treated with indoleacetic acid + benzyladenine + aminooxyacetic acid + LiCl. The enzyme has a specific activity of 35,000 nmol/h/mg protein, a pH optimum of 9.5, an isoelectric point of 5.0, a Km of 17 microM with respect to S-adenosylmethionine, and is a dimer of two identical subunits of approximately 46,000 Da each. The subunit exists in vivo as a 55,000-Da species similar in size to the primary in vitro translation product. DNA sequence analysis of the cDNA clone pACC1 revealed that the coding region of the ACC synthase mRNA spans 493 amino acids corresponding to a 55,779-Da polypeptide; and expression of the coding sequence (pACC1) in Escherichia coli as a COOH terminus hybrid of beta-galactosidase or as a nonhybrid polypeptide catalyzed the conversion of S-adenosylmethionine to ACC (Sato, T., and Theologis, A. (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 6621-6625). Immunoblotting experiments herein show that the molecular mass of the beta-galactosidase hybrid polypeptide is 170,000 Da, and the size of the largest nonhybrid polypeptide is 53,000 Da. The data suggest that the enzyme is post-translationally processed during protein purification.
Elevated striatal γ-aminobutyric acid in youth with major depressive disorder.
Bradley, Kailyn A; Alonso, Carmen M; Mehra, Lushna M; Xu, Junqian; Gabbay, Vilma
2018-06-08
Alterations in γ-aminobutyric acid (GABA) have been hypothesized to play a role in the pathogenesis of psychiatric illness. Our previous work has specifically linked anterior cingulate cortex (ACC) GABA deficits with anhedonia in youth with major depressive disorder (MDD). As anhedonia reflects alterations within the reward circuitry, we sought to extend this investigation and examine GABA levels in another key reward-related region, the striatum, in the same adolescent population. Thirty-six youth [20 with MDD and 16 healthy controls; (HC)], ages 12 to 21 years old, underwent J-edited proton magnetic resonance spectroscopy ( 1 H MRS) whereby GABA levels were measured in striatal and ACC voxels. GABA levels were compared between groups and between voxel positions and were examined in relation to clinical symptomatology, such as depression severity, anhedonia, anxiety, and suicidality. Depressed youth had unexpectedly higher GABA levels in the striatum compared to HC. In both depressed and healthy youth, GABA levels were higher in the striatum than in the ACC, while the differences in depressed youth were greater. Moreover, in depressed youth, higher striatal GABA above the mean of HCs was correlated with lower ACC GABA below the mean of HCs. Striatal GABA was not correlated with clinical symptomatology in this small sample. Together, these findings suggest that higher striatal GABA levels may serve some compensatory function as a result of lower ACC GABA in depressed adolescents. It is also possible that, like lower ACC GABA, higher striatal GABA might simply be another pathological feature of adolescent depression. Copyright © 2018 Elsevier Inc. All rights reserved.
Taurine elevates dopamine levels in the rat nucleus accumbens; antagonism by strychnine.
Ericson, Mia; Molander, Anna; Stomberg, Rosita; Söderpalm, Bo
2006-06-01
The mesolimbic dopamine (DA) system, projecting from the ventral tegmental area (VTA) to the nucleus accumbens (nAcc), is involved in reward-related behaviours and addictive processes, such as alcoholism and drug addiction. It was recently suggested that strychnine-sensitive glycine receptors (GlyR) in the nAcc regulate both basal and ethanol-induced mesolimbic DA activity via a neuronal loop involving endogenous activation of nicotinic acetylcholine receptors (nAChR) in the VTA. However, as the nAcc appears to contain few glycine-immunoreactive cell bodies or fibres, the question as to what may be the endogenous ligand for GlyRs in this brain region remains open. Here we have investigated whether the amino acid taurine could serve this purpose using in vivo microdialysis in awake, freely moving male Wistar rats. Local perfusion of taurine (1, 10 or 100 mm in the perfusate) increased DA levels in the nAcc. The taurine (10 mm)-induced DA increase was, similarly to that previously observed after ethanol, completely blocked by (i) perfusion of the competitive GlyR antagonist strychnine in the nAcc, (ii) perfusion of the nAChR antagonist mecamylamine (100 microm) in the VTA, and (iii) systemic administration of the acetylcholine-depleting drug vesamicol (0.4 mg/kg, i.p). The present results suggest that taurine may be an endogenous ligand for GlyRs in the nAcc and that the taurine-induced elevation of DA levels in this area, similarly to that observed after local ethanol, is mediated via a neuronal loop involving endogenous activation of nAChRs in the VTA.
Fukunaga, Rena; Brown, Joshua W.; Bogg, Tim
2012-01-01
The inferior frontal gyrus/anterior insula (IFG/AI) and anterior cingulate cortex (ACC) are key regions involved in risk appraisal during decision making, but accounts of how these regions contribute to decision-making under risk remain contested. To help clarify the roles of these and other related regions, we used a modified version of the Balloon Analogue Risk Task (Lejuez et al., 2002) to distinguish between decision-making and feedback-related processes when participants decided to pursue a gain as the probability of loss increased parametrically. Specifically, we set out to test whether ACC and IFG/AI regions correspond to loss-aversion at the time of decision making in a way that is not confounded with either reward-seeking or infrequency effects. When participants chose to discontinue inflating the balloon (win option), we observed greater ACC and mainly bilateral IFG/AI activity at the time of decision as the probability of explosion increased, consistent with increased loss-aversion but inconsistent with an infrequency effect. In contrast, we found robust vmPFC activity when participants chose to continue inflating the balloon (risky option), consistent with reward-seeking. However, in the cingulate and mainly bilateral IFG regions, BOLD activation decreased when participants chose to inflate the balloon as the probability of explosion increased, findings consistent with a reduced loss-aversion signal. Our results highlight the existence of distinct reward-seeking and loss-averse signals during decision-making, as well as the importance of distinguishing decision and feedback signals. PMID:22707378
Gap winds and their effects on regional oceanography Part II: Kodiak Island, Alaska
NASA Astrophysics Data System (ADS)
Ladd, Carol; Cheng, Wei; Salo, Sigrid
2016-10-01
Frequent gap winds, defined here as offshore-directed flow channeled through mountain gaps, have been observed near Kodiak Island in the Gulf of Alaska (GOA). Gap winds from the Iliamna Lake gap were investigated using QuikSCAT wind data. The influence of these wind events on the regional ocean was examined using satellite and in situ data combined with Regional Ocean Modeling System (ROMS) model runs. Gap winds influence the entire shelf width (> 200 km) northeast of Kodiak Island and extend an additional 150 km off-shelf. Due to strong gradients in the along-shelf direction, they can result in vertical velocities in the ocean of over 20 m d-1 due to Ekman pumping. The wind events also disrupt flow of the Alaska Coastal Current (ACC), resulting in decreased flow down Shelikof Strait and increased velocities on the outer shelf. This disruption of the ACC has implications for freshwater transport into the Bering Sea. The oceanographic response to gap winds may influence the survival of larval fishes as Arrowtooth Flounder recruitment is negatively correlated with the interannual frequency of gap-wind events, and Pacific Cod recruitment is positively correlated. The frequency of offshore directed winds exhibits a strong seasonal cycle averaging 7 days per month during winter and 2 days per month during summer. Interannual variability is correlated with the Pacific North America Index and shows a linear trend, increasing by 1.35 days per year. An accompanying paper discusses part I of our study (Ladd and Cheng, 2016) focusing on gap-wind events flowing out of Cross Sound in the eastern GOA.
Fukunaga, Rena; Bogg, Tim; Finn, Peter R; Brown, Joshua W
2013-12-01
A sizable segment of addiction research investigates the effects of persuasive message appeals on risky and deleterious behaviors. However, to date, little research has examined how various forms of message framing and corresponding behavioral choices might by mediated by risk-related brain regions. Using event-related functional MRI, we investigated brain regions hypothesized to mediate the influence of message appeals on decision making in substance-dependent (SD) compared with nonsubstance-dependent (non-SD) individuals. The Iowa Gambling Task (IGT) was modified to include positively-framed, negatively-framed, and control messages about long-term deck payoffs. In the positively-framed condition, the SD and non-SD groups showed improved decision-making performance that corresponded to higher risk-aversion-related brain activity in the anterior cingulate cortex (ACC) and anterior insula (AI). In contrast, in the negatively-framed condition, the SD group showed poorer performance that corresponded to lower risk-aversion-related brain activity in the AI region. In addition, only the non-SD group showed a positive association between decision quality and greater risk-related activity in the ACC, regardless of message type. The findings suggest substance-dependent individuals may have reduced neurocognitive sensitivity in the ACC and AI regions involved in risk perception and aversion during decision-making, especially in response to framed messages that emphasize reduced prospects for long-term gains. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Li, Junyi; Yuan, Yongsheng; Wang, Min; Zhang, Jiejin; Zhang, Li; Jiang, Siming; Ding, Jian; Zhang, Kezhong
2017-10-01
Fatigue is a common complaint in patients with Parkinson's disease (PD). However, the neural bases of fatigue in PD remain uncertain. In this cross-sectional study, our aim was to study the change of the local brain function in PD patients with fatigue. Among 49 patients with PD, 17 of them had fatigue and the remaining 32 patients without fatigue, and 25 age- and gender-matched healthy controls were enrolled. All subjects were evaluated with Fatigue Severity Scale (FSS) and had a resting-state functional magnetic resonance imaging (rs-fMRI) scan. The fMRI images were analyzed using regional homogeneity (ReHo) to study the change of the local brain function. ReHo analysis controlling for gray matter volume, age, gender, and education showed decreased ReHo in the left anterior cingulate cortex (ACC) and the right superior frontal gyrus (dorsolateral part), and increased ReHo in the left postcentral gyrus and the right inferior frontal gyrus (orbital and triangular part), compared PD-F with PD-NF; In PD patients, the regional activity in the left ACC and the right superior frontal gyrus (dorsolateral part) was negatively correlated with the FSS scores, while that in the left postcentral gyrus, the right inferior frontal gyrus (orbital and triangular part) was positively correlated with the FSS scores. This study demonstrates that brain areas including frontal, postcentral and ACC regions indicative of sensory, motor, and cognitive systems are involved in fatigue in PD patients.
Russo, Jennifer F; Sheth, Sameer A
2015-06-01
Chronic neuropathic pain is estimated to affect 3%-4.5% of the worldwide population. It is associated with significant loss of productive time, withdrawal from the workforce, development of mood disorders such as depression and anxiety, and disruption of family and social life. Current medical therapeutics often fail to adequately treat chronic neuropathic pain. Deep brain stimulation (DBS) targeting subcortical structures such as the periaqueductal gray, the ventral posterior lateral and medial thalamic nuclei, and the internal capsule has been investigated for the relief of refractory neuropathic pain over the past 3 decades. Recent work has identified the dorsal anterior cingulate cortex (dACC) as a new potential neuromodulation target given its central role in cognitive and affective processing. In this review, the authors briefly discuss the history of DBS for chronic neuropathic pain in the United States and present evidence supporting dACC DBS for this indication. They review existent literature on dACC DBS and summarize important findings from imaging and neurophysiological studies supporting a central role for the dACC in the processing of chronic neuropathic pain. The available neurophysiological and empirical clinical evidence suggests that dACC DBS is a viable therapeutic option for the treatment of chronic neuropathic pain and warrants further investigation.
Ghorayeb, Nada El; Rondeau, Geneviève; Latour, Mathieu; Cohade, Christian; Olney, Harold; Lacroix, André; Perrotte, Paul; Sabourin, Alexis; Mazzuco, Tania L; Bourdeau, Isabelle
2016-01-01
Abstract Mitotane has been used for more than 5 decades as therapy for adrenocortical carcinoma (ACC). However its mechanism of action and the extent of tumor response remain incompletely understood. To date no cases of rapid and complete remission of metastatic ACC with mitotane monotherapy has been reported. A 52-year-old French Canadian man presented with metastatic disease 2 years following a right adrenalectomy for stage III nonsecreting ACC. He was started on mitotane which was well tolerated despite rapid escalation of the dose. The patient course was exceptional as he responded to mitotane monotherapy after only few months of treatment. Initiation of chemotherapy was not needed and he remained disease-free with good quality of life on low maintenance dose of mitotane during the following 10 years. A germline heterozygous TP53 exon 4 polymorphism c.215C>G (p. Pro72Arg) was found. Immunohistochemical stainings for IGF-2 and cytoplasmic β-catenin were positive. Advanced ACC is an aggressive disease with poor prognosis and the current therapeutic options remain limited. These findings suggest that mitotane is a good option for the treatment of metastatic ACC and might result in rapid complete remission in selected patients. PMID:27043680
Tikàsz, Andràs; Potvin, Stéphane; Lungu, Ovidiu; Joyal, Christian C; Hodgins, Sheilagh; Mendrek, Adrianna; Dumais, Alexandre
2016-01-01
Evidence suggests a 2.1-4.6 times increase in the risk of violent behavior in schizophrenia compared to the general population. Current theories propose that the processing of negative emotions is defective in violent individuals and that dysfunctions within the neural circuits involved in emotion processing are implicated in violence. Although schizophrenia patients show enhanced sensitivity to negative stimuli, there are only few functional neuroimaging studies that have examined emotion processing among men with schizophrenia and a history of violence. The present study aimed to identify the brain regions with greater neurofunctional alterations, as detected by functional magnetic resonance imaging during an emotion processing task, of men with schizophrenia who had engaged in violent behavior compared with those who had not. Sixty men were studied; 20 with schizophrenia and a history of violence, 19 with schizophrenia and no violence, and 21 healthy men were scanned while viewing positive, negative, and neutral images. Negative images elicited hyperactivations in the anterior cingulate cortex (ACC), left and right lingual gyrus, and the left precentral gyrus in violent men with schizophrenia, compared to nonviolent men with schizophrenia and healthy men. Neutral images elicited hyperactivations in the right and left middle occipital gyrus, left lingual gyrus, and the left fusiform gyrus in violent men with schizophrenia, compared to the other two groups. Violent men with schizophrenia displayed specific increases in ACC in response to negative images. Given the role of the ACC in information integration, these results indicate a specific dysfunction in the processing of negative emotions that may trigger violent behavior in men with schizophrenia.
NASA Astrophysics Data System (ADS)
Meredith, Michael P.; Meijers, Andrew S.; Naveira Garabato, Alberto C.; Brown, Peter J.; Venables, Hugh J.; Abrahamsen, E. Povl; Jullion, Loïc.; Messias, Marie-José
2015-01-01
The waters of the Weddell-Scotia Confluence (WSC) lie above the rugged topography of the South Scotia Ridge in the Southern Ocean. Meridional exchanges across the WSC transfer water and tracers between the Antarctic Circumpolar Current (ACC) to the north and the subpolar Weddell Gyre to the south. Here, we examine the role of topographic interactions in mediating these exchanges, and in modifying the waters transferred. A case study is presented using data from a free-drifting, intermediate-depth float, which circulated anticyclonically over Discovery Bank on the South Scotia Ridge for close to 4 years. Dimensional analysis indicates that the local conditions are conducive to the formation of Taylor columns. Contemporaneous ship-derived transient tracer data enable estimation of the rate of isopycnal mixing associated with this column, with values of O(1000 m2/s) obtained. Although necessarily coarse, this is of the same order as the rate of isopycnal mixing induced by transient mesoscale eddies within the ACC. A picture emerges of the Taylor column acting as a slow, steady blender, retaining the waters in the vicinity of the WSC for lengthy periods during which they can be subject to significant modification. A full regional float data set, bathymetric data, and a Southern Ocean state estimate are used to identify other potential sites for Taylor column formation. We find that they are likely to be sufficiently widespread to exert a significant influence on water mass modification and meridional fluxes across the southern edge of the ACC in this sector of the Southern Ocean.
Resting State Synchrony in Long-Term Abstinent Alcoholics
Camchong, Jazmin; Stenger, Andy; Fein, George
2012-01-01
BACKGROUND Alcohol dependence (ALC) is a disorder with an impulsive and compulsive “drive” towards alcohol consumption and an inability to inhibit alcohol consumption. Neuroimaging studies suggest that these behavioral components correspond to an increased involvement of regions that mediate appetitive drive and reduced involvement of regions that mediate executive control within top-down networks. Little is known, however, about whether these characteristics are present after long periods of abstinence. METHODS Resting state functional magnetic resonance imaging data were collected to examine resting state synchrony (RSS) differences between 23 long-term abstinent alcoholics (LTAA; 8 females, age: M=48.46, SD=7.10), and 23 non-substance abusing controls (NSAC; 8 females, age: M=47.99, SD=6.70). Using seed-based measures, we examined resting-state synchrony with the nucleus accumbens (NAcc) and the subgenual anterior cingulate cortex (ACC). All participants were assessed with the intra/extradimensional set shift task outside of the scanner to explore the relationship between RSS and cognitive flexibility. RESULTS Compared to NSAC, LTAA showed (a) decreased synchrony of limbic reward regions (e.g., caudate and thalamus) with both the ACC seed and the NAcc seed and (b) increased synchrony of executive control regions (e.g., DLPFC) with both the NAcc seed and the subgenual ACC seed. RSS differences were significantly correlated with task performance. CONCLUSIONS The results are consistent with an interpretation of an ongoing compensatory mechanism in long-term abstinent alcoholics evident during rest, in which decision making networks show reduced synchrony with appetitive drive regions and increased synchrony with inhibitory control regions. In addition, RSS differences were associated with cognitive flexibility. These resting state findings indicate an adaptive mechanism present in long-term abstinence that may facilitate the behavioral control required for to maintain abstinence. PMID:22725701
Preliminary results from DIMES: Dispersion in the ACC
NASA Astrophysics Data System (ADS)
Balwada, D.; Speer, K.; LaCasce, J. H.; Owens, B.
2012-04-01
The Diapycnal and Isopynal Mixing Experiment in the Southern Ocean (DIMES) is a CLIVAR process study designed to study mixing in the Antarctic Circumpolar Current. The experiment includes tracer release, float, and small-scale turbulence components. This presentation will report on some results of the float component, from floats deployed across the ACC in the Southeast Pacific Ocean. These are the first subsurface Lagrangian trajectories from the ACC. Floats were deployed to follow approximately a constant density surface for a period of 1-3 years. To help aid the experimental results virtual floats were advected using AVISO data and basic statistics were derived from both deployed and virtual float trajectories. Experimental design, initial results, comparison to virtual floats and single particle and relative dispersion calculations will be presented.
Chua, Wen Bing Brandon; Cheen, Hua Heng McVin; Kong, Ming Chai; Chen, Li Li; Wee, Hwee Lin
2016-10-01
Background Oral anticoagulation with warfarin is the cornerstone therapy in atrial fibrillation (AF) for stroke prevention. Multi-disciplinary anticoagulation management services have been shown to be cost-effective in the United States, Hong Kong and Thailand, but the findings are not readily generalizable to Singapore's healthcare system. Objective This study aimed to evaluate the cost-effectiveness of pharmacist-managed anticoagulation clinic (ACC) compared with usual care (UC) for the management of older adults with AF receiving oral anticoagulation with warfarin. Setting Pharmacist-managed ACC in an academic medical centre. Method A Markov model with 3-month cycle length and 30-year time horizon compared costs and quality-adjusted life-years (QALYs) of ACC and UC from the patient's and healthcare provider's perspectives. Four pathways based on time in therapeutic range (TTR) were: ACC TTR < 70 %, ACC TTR ≥ 70 %, UC TTR < 70 % and UC TTR ≥ 70 %. A hypothetical cohort of 70-year-old Singaporean AF patients receiving warfarin was utilised. Local data from national disease registries, patient surveys and hospital databases were used. When local data was not available, published studies on Asian populations were utilized when available. One-way sensitivity analyses and probabilistic sensitivity analyses were performed to account for uncertainties. Costs and QALYs were discounted annually by 3 %. Main outcome measure Costs and QALYs of ACC and UC. Results Pharmacist-managed ACC was found to dominate UC in all comparisons. It improved effectiveness by 0.19 and 0.13 QALYs at TTR < 70 % and TTR ≥ 70 % respectively compared with UC. From the patient's perspective, ACC reduced costs by SG$1222.67 (€1110.24) for TTR < 70 % and SG$1008.16 (€915.46) for TTR ≥ 70 %. Similar trends were observed from the healthcare provider's perspective, with ACC reducing costs by SG$1444.79 (€1311.94) for TTR < 70 % and SG$1269.17 (€1152.46) for TTR ≥ 70 % compared with UC. The results were robust to variations of the parameters over their plausible ranges in one-way sensitivity analyses. Probabilistic sensitivity analyses demonstrated that ACC was cost-effective more than 79 % of the time from both perspectives at a willingness-to-pay threshold of SG$69,050 (€62,701) per QALY. Conclusion Pharmacist-managed ACC is more effective and less costly compared with UC regardless of the quality of anticoagulation therapy. The findings support the current body of evidence demonstrating the cost-effectiveness of ACC.
O'Nions, Elizabeth J P; Dolan, Raymond J; Roiser, Jonathan P
2011-11-01
This study assessed the impact of serotonin transporter genotype (5-HTTLPR) on regional responses to emotional faces in the amygdala and subgenual cingulate cortex (sgACC), while subjects performed a gender discrimination task. Although we found no evidence for greater amygdala reactivity or reduced amygdala-sgACC coupling in short variant 5-HTTLPR homozygotes (s/s), we observed an interaction between genotype and emotion in sgACC. Only long variant homozygotes (la/la) exhibited subgenual deactivation to fearful versus neutral faces, whereas the effect in s/s subjects was in the other direction. This absence of subgenual deactivation in s/s subjects parallels a recent finding in depressed subjects [Grimm, S., Boesiger, P., Beck, J., Schuepbach, D., Bermpohl, F., Walter, M., et al. Altered negative BOLD responses in the default-mode network during emotion processing in depressed subjects. Neuropsychopharmacology, 34, 932-943, 2009]. Taken together, the findings suggest that subgenual cingulate activity may play an important role in regulating the impact of aversive stimuli, potentially conferring greater resilience to the effects of aversive stimuli in la/la subjects. Using dynamic causal modeling of functional magnetic resonance imaging data, we explored the effects of genotype on effective connectivity and emotion-specific changes in coupling across a network of regions implicated in social processing. Viewing fearful faces enhanced bidirectional excitatory coupling between the amygdala and the fusiform gyrus, and increased the inhibitory influence of the amygdala over the sgACC, although this modulation of coupling did not differ between the genotype groups. The findings are discussed in relation to the role of sgACC and serotonin in moderating responses to aversive stimuli [Dayan, P., & Huys, Q. J., Serotonin, inhibition, and negative mood. PLoS Comput Biol, 4, e4, 2008; Mayberg, H. S., Liotti, M., Brannan, S. K., McGinnis, S., Mahurin, R. K., Jerabek, P. A., et al. Reciprocal limbic-cortical function and negative mood: Converging PET findings in depression and normal sadness. Am J Psychiatry, 156, 675-682, 1999].
Color-word matching stroop task: separating interference and response conflict.
Zysset, S; Müller, K; Lohmann, G; von Cramon , D Y
2001-01-01
The Stroop interference task requires a person to respond to a specific dimension of a stimulus while suppressing a competing stimulus dimension. Previous PET and fMRI studies using the Color Stroop paradigm have shown increased activity in the "cognitive division" of the cingulate cortex. In our fMRI study with nine subjects, we used a Color-Word Matching Stroop task. A frontoparietal network, including structures in the lateral prefrontal cortex, the frontopolar region, the intraparietal sulcus, as well as the lateral occipitotemporal gyrus, was activated when contrasting the incongruent vs the neutral condition. However, no substantial activation in either the right or left hemisphere of the anterior cingulate cortex (ACC) was detected. In accordance with a series of recent articles, we argue that the ACC is not specifically involved in interference processes. The ACC seems rather involved in motor preparation processes which were controlled in the present Color-Word Matching Stroop task. We argue that the region around the banks of the inferior frontal sulcus is required to solve interference problems, a concept which can also be seen as a component of task set management. Copyright 2001 Academic Press.
Pan, Wei; Zhang, Guang-Fen; Li, Hui-Hui; Ji, Mu-Huo; Zhou, Zhi-Qiang; Li, Kuan-Yu; Yang, Jian-Jun
2018-07-04
Depression is present in a large proportion of patients suffering from chronic pain, and yet the underlying mechanisms remain to be elucidated. Neuroligins (NLs), as a family of cell-adhesion proteins, are involved in synaptic formation and have been linked to various neuropsychiatric disorders. Here, we studied the alterations in NL1 and NL2 in the medial prefrontal cortex (mPFC), the anterior cingulate cortex (ACC), and the hippocampus in a rat model of neuropathic pain-induced depression, and whether ketamine, a rapid and robust antidepressant, could restore these abnormalities. In the present study, we found that spared nerve injury induced significant mechanical allodynia and subsequent depressive-like symptoms, along with decreased NL1 and increased NL2 in the mPFC, decreased NL1 in the ACC, and decreased NL2 in the hippocampus. In addition, brain-derived neurotrophic factor (BDNF) was reduced in these brain regions. It is noteworthy that ketamine (10 mg/kg) relieved neuropathic pain-induced depressive behaviors and restored alterations of BDNF and NLs in the mPFC and the hippocampus at 24 h and 72 h after the administration of ketamine, but only restored BDNF in the ACC. In conclusion, NLs showed diverse changes in different brain regions in the rat model of neuropathic pain-induced depression, which could be reversed differentially by the administration of ketamine.
Birth, life and death of an Anticyclonic eddy in the Southern Ocean
NASA Astrophysics Data System (ADS)
Torres, R.; Sallee, J. B.; Schwarz, J.; Hosegood, P. J.; Taylor, J. R.; Adams, K.; Bachman, S.; Stamper, M. A.
2016-02-01
The Antarctic Circumpolar Current (ACC) is a climatically relevant frontal structure of global importance, which regularly develops instabilities growing into meanders, and eventually evolving into long-lived anticyclonic eddies. These eddies exhibit sustained primary productivity that can last several months fuelled by local resupply of nutrients. During April-May 2015 we conducted an intensive field experiment in the Southern Ocean where we sampled and tracked an ACC meander as it developed into an eddy and later vanished some 90 days later. The physical characteristics of the meander and eddy were observed with a combination of high resolution hydrography, ADCP and turbulence observations, in addition to biogeochemical observations of nutrients and phytoplankton. The life and death of the eddy was subsequently tracked through Argo, BIO-Argo Lagrangian profilers and remote sensing. In this presentation we will use observations and ecosystem modelling to discuss the physical processes that sustain the observed high Chlorophyll levels in the eddy and explore how the eddy evolution impacts the rate of nutrient supply and how this translates into the observed changes in chlorophyll. We will discuss the relevance of eddy formation to Chlorophyll and productivity in the region.
Clarifying anti-reflexivity: conservative opposition to impact science and scientific evidence
NASA Astrophysics Data System (ADS)
Dunlap, Riley E.
2014-01-01
The recent study reported by McCright et al (2013 Environ. Res. Lett. 8 044029) extends current research on conservatives’ distrust of science by distinguishing between public trust in production versus impact scientists (i.e. those whose work yields new technologies and marketable products versus those assessing the health and environmental impacts of such technologies and products). As expected, they find that conservatives are significantly less trustful of impact scientists but somewhat more trustful of production scientists. In the process they provide support for the Anti-Reflexivity Thesis, a perspective that attributes conservatives’ (and Republicans’) denial of anthropogenic climate change (ACC) and other environmental problems and attacks on climate/environmental science to their staunch commitment to protecting the current system of economic production. McCright et al’s innovative study deserves replication, and their approach should prove useful in accounting for divergent views of ACC. It is also important to keep in mind that anti-reflexivity is an institutional and structural issue, becoming more consequential when it is employed by political elites such as the George W Bush Administration in the US. Institutional anti-reflexivity is further illustrated by the widespread denial of ACC and a range of other problems among current Republican members of the US Congress.
Experimental study of condensate subcooling with the use of a model of an air-cooled condenser
NASA Astrophysics Data System (ADS)
Sukhanov, V. A.; Bezukhov, A. P.; Bogov, I. A.; Dontsov, N. Y.; Volkovitsky, I. D.; Tolmachev, V. V.
2016-01-01
Water-supply deficit is now felt in many regions of the world. This hampers the construction of new steam-turbine and combined steam-and-gas thermal power plants. The use of dry cooling systems and, specifically, steam-turbine air-cooled condensers (ACCs) expands the choice of sites for the construction of such power plants. The significance of condensate subcooling Δ t as a parameter that negatively affects the engineering and economic performance of steam-turbine plants is thereby increased. The operation and design factors that influence the condensate subcooling in ACCs are revealed, and the research objective is, thus, formulated properly. The indicated research was conducted through physical modeling with the use of the Steam-Turbine Air-Cooled Condenser Unit specialized, multipurpose, laboratory bench. The design and the combined schematic and measurement diagram of this test bench are discussed. The experimental results are presented in the form of graphic dependences of the condensate subcooling value on cooling ratio m and relative weight content ɛ' of air in steam at the ACC inlet at different temperatures of cooling air t ca ' . The typical ranges of condensate subcooling variation (4 ≤ Δ t ≤ 6°C, 2 ≤ Δ t ≤ 4°C, and 0 ≤ Δ t ≤ 2°C) are identified based on the results of analysis of the attained Δ t levels in the ACC and numerous Δ t reduction estimates. The corresponding ranges of cooling ratio variation at different temperatures of cooling air at the ACC inlet are specified. The guidelines for choosing the adjusted ranges of cooling ratio variation with account of the results of experimental studies of the dependences of the absolute pressure of the steam-air mixture in the top header of the ACC and the heat flux density on the cooling ratio at different temperatures of cooling air at the ACC inlet are given.
NASA Astrophysics Data System (ADS)
Kuhn, G.; Wu, S.; Hass, H. C.; Klages, J. P.; Zheng, X.; Arz, H. W.; Esper, O.; Hillenbrand, C. D.; Lange, C.; Lamy, F.; Lohmann, G.; Müller, J.; McCave, I. N. N.; Nürnberg, D.; Roberts, J.; Tiedemann, R.; Timmermann, A.; Titschack, J.; Zhang, X.
2017-12-01
The evolution of the Antarctic Ice Sheet during the last climate cycle and the interrelation to global atmospheric and ocean circulation remains controversial and plays an important role for our understanding of ice sheet response to modern global warming. The timing and sequence of deglacial warming is relevant for understanding the variability and sensitivity of the Antarctic Ice Sheet to climatic changes, and the continuing rise of atmospheric greenhouse gas concentrations. The Antarctic Ice Sheet is a pivotal component of the global water budget. Freshwater fluxes from the ice sheet may affect the Antarctic Circumpolar Current (ACC), which is strongly impacted by the westerly wind belt in the Southern Hemisphere (SHWW) and constricted to its narrowest extent in the Drake Passage. The flow of ACC water masses through Drake Passage is, therefore, crucial for advancing our understanding of the Southern Ocean's role in global meridional overturning circulation and global climate change. In order to address orbital and millennial-scale variability of the Antarctic ice sheet and the ACC, we applied a multi-proxy approach on a sediment core from the central Drake Passage including grain size, iceberg-rafted debris, mineral dust, bulk chemical and mineralogical composition, and physical properties. In combination with already published and new sediment records from the Drake Passage and Scotia Sea, as well as high-resolution data from Antarctic ice cores (WDC, EDML), we now have evidence that during glacial times a more northerly extent of the perennial sea-ice zone decreased ACC current velocities in the central Drake Passage. During deglaciation the SHWW shifted southwards due to a decreasing temperature gradient between subtropical and polar latitudes caused by sea ice and ice sheet decline. This in turn caused Southern Hemisphere warming, a more vigorous ACC, stronger Southern Ocean ventilation, and warm Circumpolar Deep Water (CDW) upwelling on Antarctic shelves resulting in increased ice shelf melting. Stronger upwelling is associated with a rise in atmospheric carbon dioxide to reach a threshold at which full deglaciation could become inevitable.
Yokode, Masataka; Itai, Ryosuke; Yamashita, Yukimasa; Zen, Yoh
2017-11-01
Acinar cell carcinomas (ACCs) and mixed acinar-endocrine carcinomas (MAECs) of the pancreas are rare, accounting for only 1% of pancreatic tumors. Although both typically present at an advanced stage, chemotherapeutic regimes have not yet been standardized. A 65-year-old man presented with a large mass in the pancreatic tail with multiple liver metastases. He was initially treated with gemcitabine for suspected ductal carcinoma of the pancreas, but no response was observed. S-1, administered as second-line chemotherapy, showed an approximately 38% reduction in the size of the primary tumor and metastatic deposits with therapeutic effects being maintained for 12 months. When the tumor progressed again, he underwent a percutaneous liver biopsy, which led to the diagnosis of MAEC. Combination therapy with cisplatin and etoposide targeting the endocrine component was administered, and this was based on the endocrine component potentially being less sensitive to S-1 than the ACC element. However, therapy was stopped due to the development of neutropenia, and the patient is currently receiving best supportive care. Given the previous studies suggested that S-1 is more effective for ACCs than gemcitabine, MAECs may also respond to S-1 chemotherapy, similar to ACCs. Another potential interpretation is that S-1 was effective when the condition was ACC, and eventually showed decreased effectiveness when the condition shifted to MAEC. Future studies are needed to conclude whether S-1 chemotherapy truly works against MAECs or induces endocrine differentiation in ACCs as a part of the drug-resistance process.
Kiatpapan, Pornpimon; Kobayashi, Hajime; Sakaguchi, Maki; Ono, Hisayo; Yamashita, Mitsuo; Kaneko, Yoshinobu; Murooka, Yoshikatsu
2001-01-01
Genes for subunits of acetyl coenzyme A carboxylase (ACC), which is the enzyme that catalyzes the first step in the synthesis of fatty acids in Lactobacillus plantarum L137, were cloned and characterized. We identified six potential open reading frames, namely, manB, fabH, accB, accC, accD, and accA, in that order. Nucleotide sequence analysis suggested that fabH encoded β-ketoacyl-acyl carrier protein synthase III, that the accB, accC, accD, and accA genes encoded biotin carboxyl carrier protein, biotin carboxylase, and the β and α subunits of carboxyltransferase, respectively, and that these genes were clustered. The organization of acc genes was different from that reported for Escherichia coli, for Bacillus subtilis, and for Pseudomonas aeruginosa. E. coli accB and accD mutations were complemented by the L. plantarum accB and accD genes, respectively. The predicted products of all five genes were confirmed by using the T7 expression system in E. coli. The gene product of accB was biotinylated in E. coli. Northern and primer extension analyses demonstrated that the five genes in L. plantarum were regulated polycistronically in an acc operon. PMID:11133475
Genetic Profile of Adenoid Cystic Carcinomas (ACC) with High-Grade Transformation versus Solid Type
Costa, Ana Flávia; Altemani, Albina; Vékony, Hedy; Bloemena, Elisabeth; Fresno, Florentino; Suárez, Carlos; Llorente, José Luis; Hermsen, Mario
2010-01-01
Background: ACC can occasionally undergo dedifferentiation also referred to as high-grade transformation (ACC-HGT). However, ACC-HGT can also undergo transformation to adenocarcinomas which are not poorly differentiated. ACC-HGT is generally considered to be an aggressive variant of ACC, even more than solid ACC. This study was aimed to describe the genetic changes of ACC-HGT in relation to clinico-pathological features and to compare results to solid ACC. Methods: Genome-wide DNA copy number changes were analyzed by microarray CGH in ACC-HGT, 4 with transformation into moderately differentiated adenocarcinoma (MDA) and two into poorly differentiated carcinoma (PDC), 5 solid ACC. In addition, Ki-67 index and p53 immunopositivity was assessed. Results: ACC-HGT carried fewer copy number changes compared to solid ACC. Two ACC-HGT cases harboured a breakpoint at 6q23, near the cMYB oncogene. The complexity of the genomic profile concurred with the clinical course of the patient. Among the ACC-HGT, p53 positivity significantly increased from the conventional to the transformed (both MDA and PDC) component. Conclusion: ACC-HGT may not necessarily reflect a more advanced stage of tumor progression, but rather a transformation to another histological form in which the poorly differentiated forms (PDC) presents a genetic complexity similar to the solid ACC. PMID:20978318
Genetic profile of adenoid cystic carcinomas (ACC) with high-grade transformation versus solid type.
Costa, Ana Flávia; Altemani, Albina; Vékony, Hedy; Bloemena, Elisabeth; Fresno, Florentino; Suárez, Carlos; Llorente, José Luis; Hermsen, Mario
2010-01-01
ACC can occasionally undergo dedifferentiation also referred to as high-grade transformation (ACC-HGT). However, ACC-HGT can also undergo transformation to adenocarcinomas which are not poorly differentiated. ACC-HGT is generally considered to be an aggressive variant of ACC, even more than solid ACC. This study was aimed to describe the genetic changes of ACC-HGT in relation to clinico-pathological features and to compare results to solid ACC. genome-wide DNA copy number changes were analyzed by microarray CGH in ACC-HGT, 4 with transformation into moderately differentiated adenocarcinoma (MDA) and two into poorly differentiated carcinoma (PDC), 5 solid ACC. In addition, Ki-67 index and p53 immunopositivity was assessed. ACC-HGT carried fewer copy number changes compared to solid ACC. Two ACC-HGT cases harboured a breakpoint at 6q23, near the cMYB oncogene. The complexity of the genomic profile concurred with the clinical course of the patient. Among the ACC-HGT, p53 positivity significantly increased from the conventional to the transformed (both MDA and PDC) component. ACC-HGT may not necessarily reflect a more advanced stage of tumor progression, but rather a transformation to another histological form in which the poorly differentiated forms (PDC) presents a genetic complexity similar to the solid ACC.
Genetic profile of adenoid cystic carcinomas (ACC) with high-grade transformation versus solid type.
Costa, Ana Flávia; Altemani, Albina; Vékony, Hedy; Bloemena, Elisabeth; Fresno, Florentino; Suárez, Carlos; Llorente, José Luis; Hermsen, Mario
2011-08-01
ACC can occasionally undergo dedifferentiation also referred to as high-grade transformation (ACC-HGT). However, ACC-HGT can also undergo transformation to adenocarcinomas which are not poorly differentiated. ACC-HGT is generally considered to be an aggressive variant of ACC, even more than solid ACC. This study was aimed to describe the genetic changes of ACC-HGT in relation to clinico-pathological features, and to compare results to solid ACC. Genome wide DNA copy number changes were analyzed by microarray CGH in ACC-HGT, four with transformation into moderately differentiated adenocarcinoma (MDA) and two into poorly differentiated carcinoma (PDC), and five solid ACC. In addition, Ki67 index and p53 immunopositivity was assessed. ACC-HGT carried fewer copy number changes compared to solid ACC. Two ACC-HGT cases harboured a breakpoint at 6q23, near the cMYB oncogene. The complexity of the genomic profile concurred with the clinical course of the patient. Among the ACC-HGT, p53 positivity significantly increased from the conventional to the transformed (both MDA and PDC) component. ACC-HGT may not necessarily reflect a more advanced stage of tumor progression, but rather a transformation to another histological form in which the poorly differentiated forms (PDC) presents a genetic complexity similar to the solid ACC.
Bilingualism tunes the anterior cingulate cortex for conflict monitoring.
Abutalebi, Jubin; Della Rosa, Pasquale Anthony; Green, David W; Hernandez, Mireia; Scifo, Paola; Keim, Roland; Cappa, Stefano F; Costa, Albert
2012-09-01
Monitoring and controlling 2 language systems is fundamental to language use in bilinguals. Here, we reveal in a combined functional (event-related functional magnetic resonance imaging) and structural neuroimaging (voxel-based morphometry) study that dorsal anterior cingulate cortex (ACC), a structure tightly bound to domain-general executive control functions, is a common locus for language control and resolving nonverbal conflict. We also show an experience-dependent effect in the same region: Bilinguals use this structure more efficiently than monolinguals to monitor nonlinguistic cognitive conflicts. They adapted better to conflicting situations showing less ACC activity while outperforming monolinguals. Importantly, for bilinguals, brain activity in the ACC, as well as behavioral measures, also correlated positively with local gray matter volume. These results suggest that early learning and lifelong practice of 2 languages exert a strong impact upon human neocortical development. The bilingual brain adapts better to resolve cognitive conflicts in domain-general cognitive tasks.
Khani, Abbas; Kermani, Mojtaba; Hesam, Soghra; Haghparast, Abbas; Argandoña, Enrike G; Rainer, Gregor
2015-06-01
Despite the evidence for altered decision making in cannabis abusers, the role of the cannabinoid system in decision-making circuits has not been studied. Here, we examined the effects of cannabinoid modulation during cost-benefit decision making in the anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC), key brain areas involved in decision making. We trained different groups of rats in a delay-based and an effort-based form of cost-benefit T-maze decision-making task. During test days, the rats received local injections of either vehicle or ACEA, a cannabinoid type-1 receptor (CB1R) agonist in the ACC or OFC. We measured spontaneous locomotor activity following the same treatments and characterized CB1Rs localization on different neuronal populations within these regions using immunohistochemistry. We showed that CB1R activation in the ACC impaired decision making such that rats were less willing to invest physical effort to gain high reward. Similarly, CB1R activation in the OFC induced impulsive pattern of choice such that rats preferred small immediate rewards to large delayed rewards. Control tasks ensured that the effects were specific for differential cost-benefit tasks. Furthermore, we characterized widespread colocalizations of CB1Rs on GABAergic axonal ends but few colocalizations on glutamatergic, dopaminergic, and serotonergic neuronal ends. These results provide first direct evidence that the cannabinoid system plays a critical role in regulating cost-benefit decision making in the ACC and OFC and implicate cannabinoid modulation of synaptic ends of predominantly interneurons and to a lesser degree other neuronal populations in these two frontal regions.
Comparing the actions of lanicemine and ketamine in depression: key role of the anterior cingulate.
Downey, Darragh; Dutta, Arpan; McKie, Shane; Dawson, Gerard R; Dourish, Colin T; Craig, Kevin; Smith, Mark A; McCarthy, Dennis J; Harmer, Catherine J; Goodwin, Guy M; Williams, Steve; Deakin, J F William
2016-06-01
Intravenous infusion of lanicemine (formerly AZD6765), a low trapping non-selective N-methyl-D-aspartate (NMDA) receptor antagonist, induces antidepressant effects with a similar time course to ketamine. We investigated whether a single dose lanicemine infusion would reproduce the previously reported decrease in subgenual anterior cingulate cortex (sgACC) activity evoked by ketamine, a potential mechanism of antidepressant efficacy. Sixty un-medicated adults meeting the criteria for major depressive disorder were randomly assigned to receive constant intravenous infusions of ketamine, lanicemine or saline during a 60min pharmacological magnetic resonance imaging (phMRI) scan. Both ketamine and lanicemine gradually increased the blood oxygen level dependent signal in sgACC and rostral ACC as the primary outcome measure. No decreases in signal were seen in any region. Interviewer-rated psychotic and dissociative symptoms were minimal following administration of lanicemine. There was no significant antidepressant effect of either infusion compared to saline. The previously reported deactivation of sgACC after ketamine probably reflects the rapid and pronounced subjective effects evoked by the bolus-infusion method used in the previous study. Activation of the ACC was observed following two different NMDA compounds in both Manchester and Oxford using different 3T MRI scanners, and this effect predicted improvement in mood 1 and 7 days post-infusion. These findings suggest that the initial site of antidepressant action for NMDA antagonists may be the ACC (NCT01046630. A Phase I, Multi-centre, Double-blind, Placebo-controlled Parallel Group Study to Assess the pharmacoMRI Effects of AZD6765 in Male and Female Subjects Fulfilling the Criteria for Major Depressive Disorder; http://clinicaltrials.gov/show/NCT01046630). Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.
Yun, Je-Yeon; Jang, Joon Hwan; Jung, Wi Hoon; Shin, Na Young; Kim, Sung Nyun; Hwang, Jae Yeon
2017-01-01
Objective Executive dysfunction might be an important determinant for response to pharmacotherapy in obsessive-compulsive disorder (OCD), and could be sustained independently of symptom relief. The anterior cingulate cortex (ACC) has been indicated as a potential neural correlate of executive functioning in OCD. The present study examined the brain-executive function relationships in OCD from the ACC-based resting state functional connectivity networks (rs-FCNs), which reflect information processing mechanisms during task performance. Methods For a total of 58 subjects [OCD, n=24; healthy controls (HCs), n=34], four subdomains of executive functioning were measured using the Rey-Osterrieth Complex Figure Test (RCFT), the Stroop Color-Word Test (SCWT), the Wisconsin Card Sorting Test (WCST), and the Trail Making Test part B (TMT-B). To probe for differential patterns of the brain-cognition relationship in OCD compared to HC, the ACC-centered rs-FCN were calculated using five seed regions systemically placed throughout the ACC. Results Significant differences between the OCD group and the HCs with respect to the WCST perseverative errors, SCWT interference scores, and TMT-B reaction times (p<0.05) were observed. Moreover, significant interactions between diagnosis×dorsal ACC [S3]-based rs-FCN strength in the right dorsolateral prefrontal cortex for RCFT organization summary scores as well as between diagnosis×perigenual ACC [S7]-based rs-FCN strength in the left frontal eye field for SCWT color-word interference scores were unveiled. Conclusion These network-based neural foundations for executive dysfunction in OCD could become a potential target of future treatment, which could improve global domains of functioning broader than symptomatic relief. PMID:28539952
Variable responses of two VlMYBA gene promoters to ABA and ACC in Kyoho grape berries.
Zhai, Xiawan; Zhang, Yushu; Kai, Wenbin; Liang, Bin; Jiang, Li; Du, Yangwei; Wang, Juan; Sun, Yufei; Leng, Ping
2017-04-01
The VlMYBA subfamily of transcription factors has been known to be the functional regulators in anthocyanin biosynthesis in red grapes. In this study, the expressions of the VlMYBA1-2 and VlMYBA 2 genes, and the responses of the VlMYBA1-2/2 promoters to ABA and ACC treatments in Kyoho grape berries are examined through quantitative real-time PCR analysis and the transient expression assay. The results show that the expressions of VlMYBA1-2/2 increase dramatically after véraison and reach their highest levels when the berries are nearly fully ripe. Exogenous ABA promotes the expressions of VlMYBA1-2/2, whereas the ACC treatment increases the expression of VlMYBA2, however, it has no effect on VlMYBA1-2. The ABA treatment has a faster and stronger effect on berry pigmentation than ACC does. The VlMYBA1-2 promoter sequence contains two ABA response elements (ABRE) but no ethylene response element (ERE), whereas the VlMYBA2 promoter sequence contains two ABRE and one ERE in the upstream region of the start codon. The VlMYBA2 promoter can be activated by both ABA (more effective) and ACC, whereas the VlMYBA1-2 promoter can be activated by ABA only. In sum, ABA can promote the coloring of Kyoho grape by the promotion of VlMYBA1-2/2 transcriptions via activating the response of their promoters to ABA, whereas ethylene only regulates VlMYBA2 through the response activation of its promoter to ACC which partially enhances the coloring. Copyright © 2017 Elsevier GmbH. All rights reserved.
Touj, Sara; Houle, Sébastien; Ramla, Djamel; Jeffrey-Gauthier, Renaud; Hotta, Harumi; Bronchti, Gilles; Martinoli, Maria-Grazia; Piché, Mathieu
2017-06-03
Chronic pain is associated with autonomic disturbance. However, specific effects of chronic back pain on sympathetic regulation remain unknown. Chronic pain is also associated with structural changes in the anterior cingulate cortex (ACC), which may be linked to sympathetic dysregulation. The aim of this study was to determine whether sympathetic regulation and ACC surface and volume are affected in a rat model of chronic back pain, in which complete Freund Adjuvant (CFA) is injected in back muscles. Sympathetic regulation was assessed with renal blood flow (RBF) changes induced by electrical stimulation of a hind paw, while ACC structure was examined by measuring cortical surface and volume. RBF changes and ACC volume were compared between control rats and rats injected with CFA in back muscles segmental (T10) to renal sympathetic innervation or not (T2). In rats with CFA, chronic inflammation was observed in the affected muscles in addition to increased nuclear factor-kappa B (NF-kB) protein expression in corresponding spinal cord segments (p=0.01) as well as decreased ACC volume (p<0.05). In addition, intensity-dependent decreases in RBF during hind paw stimulation were attenuated by chronic pain at T2 (p's<0.05) and T10 (p's<0.05), but less so at T10 compared with T2 (p's<0.05). These results indicate that chronic back pain alters sympathetic functions through non-segmental mechanisms, possibly by altering descending regulatory pathways from ACC. Yet, segmental somato-sympathetic reflexes may compete with non-segmental processes depending on the back region affected by pain and according to the segmental organization of the sympathetic nervous system. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
Taren, Adrienne A.; Gianaros, Peter J.; Greco, Carol M.; Lindsay, Emily K.; Fairgrieve, April; Brown, Kirk Warren; Rosen, Rhonda K.; Ferris, Jennifer L.; Julson, Erica; Marsland, Anna L.; Bursley, James K.; Ramsburg, Jared
2015-01-01
Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects. PMID:26048176
Heat fluxes across the Antarctic Circumpolar Current
NASA Astrophysics Data System (ADS)
Ferrari, Ramiro; Provost, Christine; Hyang Park, Young; Sennéchael, Nathalie; Garric, Gilles; Bourdallé-Badie, Romain
2014-05-01
Determining the processes responsible for the Southern Ocean heat balance is fundamental to our understanding of the weather and climate systems. Therefore, in the last decades, various studies aimed at analyzing the major mechanisms of the oceanic poleward heat flux in this region. Previous works stipulated that the cross-stream heat flux due to the mesoscale transient eddies was responsible for the total meridional heat transport across the Antarctic Circumpolar Current (ACC). Several numerical modelling and current meters data studies have recently challenged this idea. These showed that the heat flux due to the mean flow in the southern part of the Antarctic Circumpolar Current could be larger than the eddy heat flux contribution by two orders of magnitude. Eddy heat flux and heat flux by the mean flow distributions of were examined in Drake Passage using in situ measurements collected during the DRAKE 2006-9 project (from January 2006 to March 2009), available observations from the historical DRAKE 79 experiment and high resolution model outputs (ORCA 12, MERCATOR). The Drake Passage estimations provided a limited view of heat transport in the Southern Ocean. The small spatial scales shown by the model derived heat flux by the mean flow indicate that circumpolar extrapolations from a single point observation are perilous. The importance of the heat flux due by the mean flow should be further investigated using other in situ observations and numerical model outputs. Similar situation has been observed, with important implication for heat flux due to the mean flow, in other topographically constricted regions with strong flow across prominent submarine ridges (choke points). We have estimated the heat flux due to the mean flow revisiting other ACC mooring sites where in situ time series are available, e.g. south of Australia (Tasmania) (Phillips and Rintoul, 2000), southeast of New Zealand (Campbell Plateau) (Bryden and Heath, 1985). Heat fluxes due to the mean flow at those choke points were compared to model outputs and provided new circumpolar estimates indicating that the choke points are a potential overwhelming contribution for the heat flux needed to balance heat lost to the atmosphere in the Southern Ocean.
Solomon, Marjorie; Ragland, J. Daniel; Niendam, Tara A.; Lesh, Tyler A.; Beck, Jonathan S.; Matter, John C.; Frank, Michael J.; Carter, Cameron S.
2015-01-01
Objective To investigate the neural mechanisms underlying impairments in generalizing learning shown by adolescents with autism spectrum disorder (ASD). Method Twenty-one high-functioning individuals with ASD aged 12–18 years, and 23 gender, IQ, and age-matched adolescents with typical development (TYP) completed a transitive inference (TI) task implemented using rapid event-related functional magnetic resonance imaging (fMRI). They were trained on overlapping pairs in a stimulus hierarchy of colored ovals where A>B>C>D>E>F and then tested on generalizing this training to new stimulus pairings (AF, BD, BE) in a “Big Game.” Whole-brain univariate, region of interest, and functional connectivity analyses were used. Results During training, TYP exhibited increased recruitment of the prefrontal cortex (PFC), while the group with ASD showed greater functional connectivity between the PFC and the anterior cingulate cortex (ACC). Both groups recruited the hippocampus and caudate comparably; however, functional connectivity between these regions was positively associated with TI performance for only the group with ASD. During the Big Game, TYP showed greater recruitment of the PFC, parietal cortex, and the ACC. Recruitment of these regions increased with age in the group with ASD. Conclusion During TI, TYP recruited cognitive control-related brain regions implicated in mature problem solving/reasoning including the PFC, parietal cortex, and ACC, while the group with ASD showed functional connectivity of the hippocampus and the caudate that was associated with task performance. Failure to reliably engage cognitive control-related brain regions may produce less integrated flexible learning in those with ASD unless they are provided with task support that in essence provides them with cognitive control, but this pattern may normalize with age. PMID:26506585
Xiuwen, Yang; Hongchen, Liu; Ke, Li; Zhen, Jin; Gang, Liu
2014-12-01
We used functional magnetic resonance imaging (fMRI) to explore the effects of noxious coldness and non-noxious warmth on the magnitude of cerebral cortex activation during intraoral stimulation with water. Six male and female subjects were subjected to whole-brain fMRI during the phasic delivery of non-noxious hot (23 °C) and no- xious cold (4 °C) water intraoral stimulation. A block-design blood oxygenation level-dependent fMRI scan covering the entire brain was also carried out. The activated cortical areas were as follows: left pre-/post-central gyrus, insula/operculum, anterior cingulate cortex (ACC), orbital frontal cortex (OFC), midbrain red nucleus, and thalamus. The activated cortical areas under cold condition were as follows: left occipital lobe, premotor cortex/Brodmann area (BA) 6, right motor language area BA44, lingual gyrus, parietal lobule (BA7, 40), and primary somatosensory cortex S I. Comparisons of the regional cerebral blood flow response magnitude were made among stereotactically concordant brain regions that showed significant responses under the two conditions of this study. Compared with non-noxious warmth, more regions were activated in noxious coldness, and the magnitude of activation in areas produced after non-noxious warm stimulation significantly increased. However, ACC only significantly increased the magnitude of activation under noxious coldness stimulation. Results suggested that a similar network of regions was activated common to the perception of pain and no-pain produced by either non-noxious warmth or noxious coldness stimulation. Non-noxious warmth also activated more brain regions and significantly increased the response magnitude of cerebral-cortex activation compared with noxious coldness. Noxious coldness stimulation further significantly increased the magnitude of activation in ACC areas compared with noxious warmth.
Fukunaga, Rena; Brown, Joshua W; Bogg, Tim
2012-09-01
The inferior frontal gyrus/anterior insula (IFG/AI) and anterior cingulate cortex (ACC) are key regions involved in risk appraisal during decision making, but accounts of how these regions contribute to decision making under risk remain contested. To help clarify the roles of these and other related regions, we used a modified version of the Balloon Analogue Risk Task (Lejuez et al., Journal of Experimental Psychology: Applied, 8, 75-84, 2002) to distinguish between decision-making and feedback-related processes when participants decided to pursue a gain as the probability of loss increased parametrically. Specifically, we set out to test whether the ACC and IFG/AI regions correspond to loss aversion at the time of decision making in a way that is not confounded with either reward-seeking or infrequency effects. When participants chose to discontinue inflating the balloon (win option), we observed greater ACC and mainly bilateral IFG/AI activity at the time of decision as the probability of explosion increased, consistent with increased loss aversion but inconsistent with an infrequency effect. In contrast, we found robust vmPFC activity when participants chose to continue inflating the balloon (risky option), consistent with reward seeking. However, in the cingulate and in mainly bilateral IFG regions, blood-oxygenation-level-dependent activation decreased when participants chose to inflate the balloon as the probability of explosion increased, findings that are consistent with a reduced loss aversion signal. Our results highlight the existence of distinct reward-seeking and loss-averse signals during decision making, as well as the importance of distinguishing between decision and feedback signals.
Zeeb, Fiona D; Baarendse, P J J; Vanderschuren, L J M J; Winstanley, Catharine A
2015-12-01
Studies employing the Iowa Gambling Task (IGT) demonstrated that areas of the frontal cortex, including the ventromedial prefrontal cortex, orbitofrontal cortex (OFC), dorsolateral prefrontal cortex, and anterior cingulate cortex (ACC), are involved in the decision-making process. However, the precise role of these regions in maintaining optimal choice is not clear. We used the rat gambling task (rGT), a rodent analogue of the IGT, to determine whether inactivation of or altered dopamine signalling within discrete cortical sub-regions disrupts decision-making. Following training on the rGT, animals were implanted with guide cannulae aimed at the prelimbic (PrL) or infralimbic (IL) cortices, the OFC, or the ACC. Prior to testing, rats received an infusion of saline or a combination of baclofen and muscimol (0.125 μg of each/side) to inactivate the region and an infusion of a dopamine D2 receptor antagonist (0, 0.1, 0.3, and 1.0 μg/side). Rats tended to increase their choice of a disadvantageous option and decrease their choice of the optimal option following inactivation of either the IL or PrL cortex. In contrast, OFC or ACC inactivation did not affect decision-making. Infusion of a dopamine D2 receptor antagonist into any sub-region did not alter choice preference. Online activity of the IL or PrL cortex is important for maintaining an optimal decision-making strategy, but optimal performance on the rGT does not require frontal cortex dopamine D2 receptor activation. Additionally, these results demonstrate that the roles of different cortical regions in cost-benefit decision-making may be dissociated using the rGT.
Eddy response to variable atmospheric forcing in the Southern Ocean
NASA Astrophysics Data System (ADS)
Ward, M. L.; McC. Hogg, A.
2009-04-01
Satellite altimeter data of the Southern Ocean (SO) reveal an anomalous peak in eddy kinetic energy (EKE) in the Antarctic Circumpolar Current (ACC) in 2000-2002. This peak has been attributed to a delayed response to an earlier peak in the Southern Annular Mode (SAM) and its associated circumpolar eastward winds that occurred around 1998, where the delay is due to the formation and adjustment of the eddy field associated with the increased winds (Meredith & Hogg, 2006). A more recent analysis reveals that the EKE response varies regionally, with the strongest response in the Pacific, and it has been suggested that this variability is due to the additional influence of ENSO. The 2000-2002 peak in EKE is therefore attributed to the coincident peak in SAM and ENSO 2-3 years earlier, and that the EKE response was weaker in past years when modes were out of phase (Morrow & Pasquet, 2008). We investigate this issue by applying SAM-like and ENSO-like wind forcings to Q-GCM, the eddy-resolving model used in Meredith & Hogg and configured for the Southern Ocean. We analyze the EKE response to each individual forcing as well as a simultaneous forcing of the two, both in and out of phase. From these results, we are able to quantify both the global and regional response to each forcing, and the degree to which each mode is responsible for the EKE strength and distribution across the ACC.
The functional anatomy of suggested limb paralysis.
Deeley, Quinton; Oakley, David A; Toone, Brian; Bell, Vaughan; Walsh, Eamonn; Marquand, Andre F; Giampietro, Vincent; Brammer, Michael J; Williams, Steven C R; Mehta, Mitul A; Halligan, Peter W
2013-02-01
Suggestions of limb paralysis in highly hypnotically suggestible subjects have been employed to successfully model conversion disorders, revealing similar patterns of brain activation associated with attempted movement of the affected limb. However, previous studies differ with regard to the executive regions involved during involuntary inhibition of the affected limb. This difference may have arisen as previous studies did not control for differences in hypnosis depth between conditions and/or include subjective measures to explore the experience of suggested paralysis. In the current study we employed functional magnetic resonance imaging (fMRI) to examine the functional anatomy of left and right upper limb movements in eight healthy subjects selected for high hypnotic suggestibility during (i) hypnosis (NORMAL) and (ii) attempted movement following additional left upper limb paralysis suggestions (PARALYSIS). Contrast of left upper limb motor function during NORMAL relative to PARALYSIS conditions revealed greater activation of contralateral M1/S1 and ipsilateral cerebellum, consistent with the engagement of these regions in the completion of movements. By contrast, two significant observations were noted in PARALYSIS relative to NORMAL conditions. In conjunction with reports of attempts to move the paralysed limb, greater supplementary motor area (SMA) activation was observed, a finding consistent with the role of SMA in motor intention and planning. The anterior cingulate cortex (ACC, BA 24) was also significantly more active in PARALYSIS relative to NORMAL conditions - suggesting that ACC (BA 24) may be implicated in involuntary, as well as voluntary inhibition of prepotent motor responses. Copyright © 2012 Elsevier Ltd. All rights reserved.
Sheth, Chandni; Prescot, Andrew; Bueler, Elliott; DiMuzio, Jennifer; Legarreta, Margaret; Renshaw, Perry F; Yurgelun-Todd, Deborah; McGlade, Erin
2018-06-30
Studies investigating the neurochemical changes that correspond with suicidal behavior (SB) have not yielded conclusive results. Suicide correlates such as aggression have been used to explore risk factors for SB. Yet the neurobiological basis for the association between aggression and SB is unclear. Aggression and SB are both prevalent in veterans relative to civilian populations. The current study evaluated the relationship between brain chemistry in the anterior (ACC) and the posterior cingulate cortex (POC), as well as the relationship between aggression and SB in a veteran population using proton magnetic resonance spectroscopy ( 1 H-MRS). Single-voxel MRS data at 3 Tesla (T) were acquired from the ACC and POC voxels using a 2-dimensional J-resolved point spectroscopy sequence and quantified using the ProFit algorithm. Participants also completed a structured diagnostic interview and a clinical battery. Our results showed that the myoinositol (mI)/H2O ratio in the ACC and POC was significantly higher in veterans who reported SB when compared to veterans who did not. The two groups did not differ significantly with regard to other metabolites. Second, verbal aggression and SB measures positively correlated with mI/H2O in the ACC. Finally, verbal aggression mediated the relationship between mI/H2O in the ACC and SB. Copyright © 2018 Elsevier B.V. All rights reserved.
Dissociable effects of surprise and model update in parietal and anterior cingulate cortex
O’Reilly, Jill X.; Schüffelgen, Urs; Cuell, Steven F.; Behrens, Timothy E. J.; Mars, Rogier B.; Rushworth, Matthew F. S.
2013-01-01
Brains use predictive models to facilitate the processing of expected stimuli or planned actions. Under a predictive model, surprising (low probability) stimuli or actions necessitate the immediate reallocation of processing resources, but they can also signal the need to update the underlying predictive model to reflect changes in the environment. Surprise and updating are often correlated in experimental paradigms but are, in fact, distinct constructs that can be formally defined as the Shannon information (IS) and Kullback–Leibler divergence (DKL) associated with an observation. In a saccadic planning task, we observed that distinct behaviors and brain regions are associated with surprise/IS and updating/DKL. Although surprise/IS was associated with behavioral reprogramming as indexed by slower reaction times, as well as with activity in the posterior parietal cortex [human lateral intraparietal area (LIP)], the anterior cingulate cortex (ACC) was specifically activated during updating of the predictive model (DKL). A second saccade-sensitive region in the inferior posterior parietal cortex (human 7a), which has connections to both LIP and ACC, was activated by surprise and modulated by updating. Pupillometry revealed a further dissociation between surprise and updating with an early positive effect of surprise and late negative effect of updating on pupil area. These results give a computational account of the roles of the ACC and two parietal saccade regions, LIP and 7a, by which their involvement in diverse tasks can be understood mechanistically. The dissociation of functional roles between regions within the reorienting/reprogramming network may also inform models of neurological phenomena, such as extinction and Balint syndrome, and neglect. PMID:23986499
Yuan, Wang; Ming, Zhang; Rana, Netra; Hai, Liu; Chen-wang, Jin; Shao-hui, Ma
2010-01-01
Pain-related studies have mainly been performed through traditional methods, which lack the rigorous analysis of anatomical locations. Functional magnetic resonance imaging (fMRI) is a noninvasive method detecting neural activity, and has the ability to precisely locate related activations in vivo. Moreover, few studies have used painful stimulation of changed intensity to investigate relevant functioning nuclei in the human brain. This study mainly focused on the pain-related activations induced by electrical stimulation with different intensities using fMRI. Furthermore, the electrophysiological characteristics of different pain-susceptible-neurons were analyzed to construct the pain modulatory network, which was corresponding to painful stimulus of changed intensity. Twelve volunteers underwent functional scanning receiving different electrical stimulation. The data were collected and analyzed to generate the corresponding functional activation maps and response time curves related to pain. The common activations were mainly located in several specific regions, including the secondary somatosensory cortex (SII), insula, anterior cingulate cortex (ACC), thalamus, and other cerebral regions. Moreover, innocuous electrical stimulation primarily activated the lateral portions of SII and thalamus, as well as the posterior insula, anterior ACC, whereas noxious electrical stimulation primarily activated the medial portions of SII and thalamus, as well as the anterior insula, the posterior ACC, with larger extensions and greater intensities. Several specified cerebral regions displayed different response patterns during electrical stimulation by means of fMRI, which implied that the corresponding pain-susceptible-neurons might process specific aspects of pain. Elucidation of functions on pain-related regions will help to understand the delicate pain modulation of human brain.
Yan, Zhiyan; Leong, May Ying; Lim, Geok Hoon
2018-01-01
Adenoid cystic carcinomas (ACC) of the breast are extremely rare tumours, accounting for <0.1% of newly diagnosed breast cancer cases. Little data exist regarding the correlation of radiological findings with histology of this rare subtype. To our knowledge, gross size discrepancy between the 2 modalities has not been reported. We describe a case of ACC with appreciable size discordance between imaging and pathology report. A 71 years old lady presented with a painless right breast lump of a few months duration. Clinical examination revealed a 1.5 cm right breast upper outer quadrant mass. Axillary and systemic examinations were unremarkable. Mammogram showed an asymmetric density in the right upper outer quadrant which corresponded to a suspicious nodule measuring about 2 cm on the ultrasound. Ultrasound of the axilla showed an indeterminate right lymph node. Core needle biopsy of the right breast nodule showed ACC while the lymph node biopsy was non- metastatic. Staging scans did not reveal any definite distant metastasis. Her naso-endoscopy and MRI of the neck were normal. She underwent a right mastectomy and sentinel lymph node biopsy. Final histology returned as a grade II 55 mm ACC. Lympho-vascular invasion was absent. The tumour was triple negative for Estrogen receptor (ER), Progesterone receptor (PR) and Human epidermal receptor 2 (HER 2). Sentinel lymph node biopsy was negative for metastasis. She recovered well but declined adjuvant chemotherapy and radiation therapy. She is currently well 6 months post operation. ACC is an extremely rare subtype, therefore there are limited reports in literature on its imaging and pathological characteristics. Of this sparse data, there was no mention that there might be a big size discrepancy between the 2 modalities. This appreciable discrepancy has implications for pre-operative planning and the choice of breast surgery. It will be useful if the pathological extent of ACC could be determined more accurately radiologically. However, there are no distinctive imaging characteristics for ACC. ACC can appear as a smooth round mass similar to that of a benign mass or as an irregular mass on mammogram. On ultrasound, ACC often manifested as a hypo- echoic heterogeneous mass with minimal vascularity on Doppler imaging and may have an indistinct margin. MRI has a higher sensitivity than mammogram and ultrasound in determining the true extent of the tumour, but there remains little data on its usefulness in ACC. ACC can be extensively infiltrative and present much larger than its radiological size, as reported in our case. Use of better imaging modalities judiciously, in these cases, are needed to more accurately predict the true pathological size of ACC to prevent inadequate surgery. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Mosebach, Jennifer; Keilhoff, Gerburg; Gos, Tomasz; Schiltz, Kolja; Schoeneck, Linda; Dobrowolny, Henrik; Mawrin, Christian; Müller, Susan; Schroeter, Matthias L; Bernstein, Hans-Gert; Bogerts, Bernhard; Steiner, Johann
2013-08-01
Structural and functional oligodendrocyte deficits as well as impaired myelin integrity have been described in affective disorders and schizophrenia, and may disturb the connectivity between disease-relevant brain regions. Olig1, an oligodendroglial transcription factor, might be important in this context, but has not been systematically studied so far. Nissl- and Olig1-stained oligodendrocytes were quantified in the pregenual anterior cingulate (pACC)/dorsolateral prefrontal cortex (DLPFC), and adjacent white matter of patients with major depressive disorder (MDD, n = 9), bipolar disorder (BD, n = 8), schizophrenia (SZ, n = 13), and matched controls (n = 16). Potential downstream effects of increased Olig1-expression were analyzed. Antidepressant drug effects on Olig1-expression were further explored in OLN-93 oligodendrocyte cultures. Nissl-stainings of both white matter regions showed a 19-27% reduction of total oligodendrocyte densities in MDD and BD, but not in SZ. In contrast, nuclear Olig1-immunoreactivity was elevated in MDD in the pACC-adjacent white matter (left: p = 0.008; right: p = 0.018); this effect tended to increase with antidepressant dosage (r = 0.631, p = 0.069). This reactive increase of Olig1 was confirmed by partly dose-dependent effects of imipramine and amitriptyline in oligodendrocyte cultures. Correspondingly, MBP expression in the pACC-adjacent white matter tended to increase with antidepressant dosage (r = 0.637, p = 0.065). Other tested brain regions showed no diagnosis-dependent differences regarding Olig1-immunoreactivity. Since nuclear Olig1-expression marks oligodendrocyte precursor cells, its increased expression along with reduced total oligodendrocyte densities (Nissl-stained) in the pACC-adjacent white matter of MDD patients might indicate a (putatively medication-boosted) regenerative attempt to compensate oligodendrocyte loss. Copyright © 2013 Elsevier Ltd. All rights reserved.
Manza, Peter; Hu, Sien; Chao, Herta H.; Zhang, Sheng; Leung, Hoi-Chung; Li, Chiang-shan R.
2016-01-01
Response inhibition and salience detection are among the most studied psychological constructs of cognitive control. Despite a growing body of work, how inhibition and salience processing interact and engage regional brain activations remains unclear. Here, we examined this issue in a stop signal task (SST), where a prepotent response needs to be inhibited to allow an alternative, less dominant response. Sixteen adult individuals performed two versions of the SST each with 25% (SST25) and 75% (SST75) of stop trials. We posited that greater regional activations to the infrequent trial type in each condition (i.e., to stop as compared to go trials in SST25 and to go as compared to stop trials in SST75) support salience detection. Further, successful inhibition in stop trials requires attention to the stop signal to trigger motor inhibition, and the stop signal reaction time (SSRT) has been used to index the efficiency of motor response inhibition. Therefore, greater regional activations to stop as compared to go success trials in association with the stop signal reaction time (SSRT) serves to expedite response inhibition. In support of an interactive role, the dorsal anterior cingulate cortex (dACC) increases activation to salience detection in both SST25 and SST75, but only mediates response inhibition in SST75. Thus, infrequency response in the dACC supports motor inhibition only when stopping has become a routine. In contrast, although the evidence is less robust, the pre-supplementary motor area (pre-SMA) increases activity to the infrequent stimulus and supports inhibition in both SST25 and SST75. These findings clarify a unique role of the dACC and add to the literature that distinguishes dACC and pre-SMA functions in cognitive control. PMID:27126003
Manza, Peter; Hu, Sien; Chao, Herta H; Zhang, Sheng; Leung, Hoi-Chung; Li, Chiang-Shan R
2016-07-01
Response inhibition and salience detection are among the most studied psychological constructs of cognitive control. Despite a growing body of work, how inhibition and salience processing interact and engage regional brain activations remains unclear. Here, we examined this issue in a stop signal task (SST), where a prepotent response needs to be inhibited to allow an alternative, less dominant response. Sixteen adult individuals performed two versions of the SST each with 25% (SST25) and 75% (SST75) of stop trials. We posited that greater regional activations to the infrequent trial type in each condition (i.e., to stop as compared to go trials in SST25 and to go as compared to stop trials in SST75) support salience detection. Further, successful inhibition in stop trials requires attention to the stop signal to trigger motor inhibition, and the stop signal reaction time (SSRT) has been used to index the efficiency of motor response inhibition. Therefore, greater regional activations to stop as compared to go success trials in association with the stop signal reaction time (SSRT) serve to expedite response inhibition. In support of an interactive role, the dorsal anterior cingulate cortex (dACC) increases activation to salience detection in both SST25 and SST75, but only mediates response inhibition in SST75. Thus, infrequency response in the dACC supports motor inhibition only when stopping has become a routine. In contrast, although the evidence is less robust, the pre-supplementary motor area (pre-SMA) increases activity to the infrequent stimulus and supports inhibition in both SST25 and SST75. These findings clarify a unique role of the dACC and add to the literature that distinguishes dACC and pre-SMA functions in cognitive control. Copyright © 2016 Elsevier Inc. All rights reserved.
Matsunaga, Masahiro; Kawamichi, Hiroaki; Koike, Takahiko; Yoshihara, Kazufumi; Yoshida, Yumiko; Takahashi, Haruka K; Nakagawa, Eri; Sadato, Norihiro
2016-07-01
Happiness is one of the most fundamental human goals, which has led researchers to examine the source of individual happiness. Happiness has usually been discussed regarding two aspects (a temporary positive emotion and a trait-like long-term sense of being happy) that are interrelated; for example, individuals with a high level of trait-like subjective happiness tend to rate events as more pleasant. In this study, we hypothesized that the interaction between the two aspects of happiness could be explained by the interaction between structure and function in certain brain regions. Thus, we first assessed the association between gray matter density (GMD) of healthy participants and trait-like subjective happiness using voxel-based morphometry (VBM). Further, to assess the association between the GMD and brain function, we conducted functional magnetic resonance imaging (MRI) using the task of positive emotion induction (imagination of several emotional life events). VBM indicated that the subjective happiness was positively correlated with the GMD of the rostral anterior cingulate cortex (rACC). Functional MRI demonstrated that experimentally induced temporal happy feelings were positively correlated with subjective happiness level and rACC activity. The rACC response to positive events was also positively correlated with its GMD. These results provide convergent structural and functional evidence that the rACC is related to happiness and suggest that the interaction between structure and function in the rACC may explain the trait-state interaction in happiness. Copyright © 2016 Elsevier Inc. All rights reserved.
Mirth and laughter elicited by electrical stimulation of the human anterior cingulate cortex.
Caruana, Fausto; Avanzini, Pietro; Gozzo, Francesca; Francione, Stefano; Cardinale, Francesco; Rizzolatti, Giacomo
2015-10-01
Laughter is a complex motor behavior that, typically, expresses mirth. Despite its fundamental role in social life, knowledge about the neural basis of laughter is very limited and mostly based on a few electrical stimulation (ES) studies carried out in epileptic patients. In these studies laughter was elicited from temporal areas where it was accompanied by mirth and from frontal areas plus an anterior cingulate case where laughter without mirth was observed. On the basis of these findings, it has been proposed a dichotomy between temporal lobe areas processing the emotional content of laughter and anterior cingulate cortex (ACC) and motor areas responsible of laughter production. The present study is aimed to understand the role of ACC in laughter. We report the effects of stimulation of 10 rostral, pregenual ACC (pACC) patients in which the ES elicited laughter. In half of the patients ES elicited a clear burst of laughter with mirth, while in the other half mirth was not evident. This large dataset allow us to offer a more reliable picture of the functional contribute of this region in laughter, and to precisely localize it in the cingulate cortex. We conclude that the pACC is involved in both the motor and the affective components of emotions, and challenge the validity of a sharp dichotomy between motor and emotional centers for laughing. Finally, we suggest a possible anatomical network for the production of positive emotional expressions. Copyright © 2015 Elsevier Ltd. All rights reserved.
Li, Z; Chang, S; Lin, L; Li, Y; An, Q
2011-08-01
1-Aminocyclopropane-1-carboxylate (ACC) deaminase activity is an efficient marker for bacteria to promote plant growth by lowering ethylene levels in plants. We aim to develop a method for rapidly screening bacteria containing ACC deaminase, based on a colorimetric ninhydrin assay of ACC. A reliable colorimetric ninhydrin assay was developed to quantify ACC using heat-resistant polypropylene chimney-top 96-well PCR plates, having the wells evenly heated in boiling water, preventing accidental contamination from boiling water and limiting evaporation. With this method to measure bacterial consumption of ACC, 44 ACC-utilizing bacterial isolates were rapidly screened out from 311 bacterial isolates that were able to grow on minimal media containing ACC as the sole nitrogen source. The 44 ACC-utilizing bacterial isolates showed ACC deaminase activities and belonged to the genus Burkholderia, Pseudomonas or Herbaspirillum. Determination of bacterial ACC consumption by the PCR-plate ninhydrin-ACC assay is a rapid and efficient method for screening bacteria containing ACC deaminase from a large number of bacterial isolates. The PCR-plate ninhydrin-ACC assay extends the utility of the ninhydrin reaction and enables a rapid screening of bacteria containing ACC deaminase from large numbers of bacterial isolates. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.
NASA Astrophysics Data System (ADS)
Sheen, K.; Naveira-Garabato, A. C.; Brearley, J. A.
2012-04-01
The principal objective of the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is to investigate the role of turbulent mixing in mediating the vertical and horizontal transport of water masses, which shape the overturning circulation. Here, microstructure and finestructure data, collected as part of this multi-component experiment, are presented. Direct observations of turbulent energy dissipation rates show that mid-depth diapycnal diffusivities increase progressively from O(10-5 m2s-1) in the Pacific sector of the Antarctic Circumpolar Current (ACC) to O(10-4 m2s-1) in the Scotia Sea. Analysis of coincident LADCP and CTD data demonstrates that enhanced turbulent dissipation rates are associated with a more energetic, less inertial internal wave field and increased upward energy propagation. Breaking lee waves, a process enhanced by stronger flow and rougher topography found in the eastern sections, is likely to be a key mechanism in determining the distribution of turbulent mixing in the ACC. Spatially varying discrepancies between the microstructure and finestructure mixing observations indicate regions where wave-wave interaction models break down and internal waves interact with the mean flow. An episodic enhancement of current velocities at 2000 m depth is observed in the northwest Scotia Sea in both LADCP and mooring data. Finestructure analysis indicates that this mid-depth jet has a profound impact of the internal wave field, causing both internal wave reflection and critical layer dissipation.
Estimates of Oceanic Eddy Heat and Salt Transports from Satellite Altimetry and Argo Profile Data.
NASA Astrophysics Data System (ADS)
Amores Maimo, A. M.; Melnichenko, O.; Maximenko, N. A.
2016-12-01
Horizontal heat and salt fluxes by mesoscale eddies are estimated in the near-global ocean (10°-60° N and 10°-60° S) by combining historical records of Argo temperature/salinity profiles and satellite sea level anomaly data in the framework of the eddy tracking technique. The eddy fluxes are expectedly strong in the western boundary currents and in the Southern Ocean along the Antarctic Circumpolar Current (ACC). The fluxes are generally weak, but not negligible in gyre interiors. In the vertical, the eddy heat and salt fluxes are surface-intensified and confined mainly to the upper 600m layer, but their distribution with depth is not homogeneous throughout the ocean. In the Kuroshio Extension (KE) region, for example, the heat flux is poleward everywhere in the surface layer above the thermocline, but oppositely signed relative to the jet's axis in a deeper layer between approximately 300-800 m, where the flux is poleward on the northern side of the jet and equatorward on its southern side. Relatively strong fluxes at depth are also observed in the ACC, particularly in the Indian sector, and in the subtropical North Atlantic at the level of the Mediterranean Water (MW) at around 1000 m depth. The latter exemplifies the role of eddies in MW spreading. These and other features of the longitude-latitude-depth distributions of the eddy heat and salt fluxes, constructed for the first time from observational data, are presented and discussed.
O'Neill, Hayley M; Lally, James S; Galic, Sandra; Pulinilkunnil, Thomas; Ford, Rebecca J; Dyck, Jason R B; van Denderen, Bryce J; Kemp, Bruce E; Steinberg, Gregory R
2015-07-01
During submaximal exercise fatty acids are a predominant energy source for muscle contractions. An important regulator of fatty acid oxidation is acetyl-CoA carboxylase (ACC), which exists as two isoforms (ACC1 and ACC2) with ACC2 predominating in skeletal muscle. Both ACC isoforms regulate malonyl-CoA production, an allosteric inhibitor of carnitine palmitoyltransferase 1 (CPT-1); the primary enzyme controlling fatty acyl-CoA flux into mitochondria for oxidation. AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that is activated during exercise or by pharmacological agents such as metformin and AICAR. In resting muscle the activation of AMPK with AICAR leads to increased phosphorylation of ACC (S79 on ACC1 and S221 on ACC2), which reduces ACC activity and malonyl-CoA; effects associated with increased fatty acid oxidation. However, whether this pathway is vital for regulating skeletal muscle fatty acid oxidation during conditions of increased metabolic flux such as exercise/muscle contractions remains unknown. To examine this we characterized mice lacking AMPK phosphorylation sites on ACC2 (S212 in mice/S221 in humans-ACC2-knock-in [ACC2-KI]) or both ACC1 (S79) and ACC2 (S212) (ACC double knock-in [ACCD-KI]) during submaximal treadmill exercise and/or ex vivo muscle contractions. We find that surprisingly, ACC2-KI mice had normal exercise capacity and whole-body fatty acid oxidation during treadmill running despite elevated muscle ACC2 activity and malonyl-CoA. Similar results were observed in ACCD-KI mice. Fatty acid oxidation was also maintained in muscles from ACC2-KI mice contracted ex vivo. These findings indicate that pathways independent of ACC phosphorylation are important for regulating skeletal muscle fatty acid oxidation during exercise/muscle contractions. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
Liu, Peng; Qin, Wei; Wang, Jingjing; Zeng, Fang; Zhou, Guangyu; Wen, Haixia; von Deneen, Karen M.; Liang, Fanrong; Gong, Qiyong; Tian, Jie
2013-01-01
Background Previous imaging studies on functional dyspepsia (FD) have focused on abnormal brain functions during special tasks, while few studies concentrated on the resting-state abnormalities of FD patients, which might be potentially valuable to provide us with direct information about the neural basis of FD. The main purpose of the current study was thereby to characterize the distinct patterns of resting-state function between FD patients and healthy controls (HCs). Methodology/Principal Findings Thirty FD patients and thirty HCs were enrolled and experienced 5-mintue resting-state scanning. Based on the support vector machine (SVM), we applied multivariate pattern analysis (MVPA) to investigate the differences of resting-state function mapped by regional homogeneity (ReHo). A classifier was designed by using the principal component analysis and the linear SVM. Permutation test was then employed to identify the significant contribution to the final discrimination. The results displayed that the mean classifier accuracy was 86.67%, and highly discriminative brain regions mainly included the prefrontal cortex (PFC), orbitofrontal cortex (OFC), supplementary motor area (SMA), temporal pole (TP), insula, anterior/middle cingulate cortex (ACC/MCC), thalamus, hippocampus (HIPP)/parahippocamus (ParaHIPP) and cerebellum. Correlation analysis revealed significant correlations between ReHo values in certain regions of interest (ROI) and the FD symptom severity and/or duration, including the positive correlations between the dmPFC, pACC and the symptom severity; whereas, the positive correlations between the MCC, OFC, insula, TP and FD duration. Conclusions These findings indicated that significantly distinct patterns existed between FD patients and HCs during the resting-state, which could expand our understanding of the neural basis of FD. Meanwhile, our results possibly showed potential feasibility of functional magnetic resonance imaging diagnostic assay for FD. PMID:23874543
Tikàsz, Andràs; Potvin, Stéphane; Lungu, Ovidiu; Joyal, Christian C; Hodgins, Sheilagh; Mendrek, Adrianna; Dumais, Alexandre
2016-01-01
Background Evidence suggests a 2.1–4.6 times increase in the risk of violent behavior in schizophrenia compared to the general population. Current theories propose that the processing of negative emotions is defective in violent individuals and that dysfunctions within the neural circuits involved in emotion processing are implicated in violence. Although schizophrenia patients show enhanced sensitivity to negative stimuli, there are only few functional neuroimaging studies that have examined emotion processing among men with schizophrenia and a history of violence. Objective The present study aimed to identify the brain regions with greater neurofunctional alterations, as detected by functional magnetic resonance imaging during an emotion processing task, of men with schizophrenia who had engaged in violent behavior compared with those who had not. Methods Sixty men were studied; 20 with schizophrenia and a history of violence, 19 with schizophrenia and no violence, and 21 healthy men were scanned while viewing positive, negative, and neutral images. Results Negative images elicited hyperactivations in the anterior cingulate cortex (ACC), left and right lingual gyrus, and the left precentral gyrus in violent men with schizophrenia, compared to nonviolent men with schizophrenia and healthy men. Neutral images elicited hyperactivations in the right and left middle occipital gyrus, left lingual gyrus, and the left fusiform gyrus in violent men with schizophrenia, compared to the other two groups. Discussion Violent men with schizophrenia displayed specific increases in ACC in response to negative images. Given the role of the ACC in information integration, these results indicate a specific dysfunction in the processing of negative emotions that may trigger violent behavior in men with schizophrenia. PMID:27366072
Modeling conflict and error in the medial frontal cortex.
Mayer, Andrew R; Teshiba, Terri M; Franco, Alexandre R; Ling, Josef; Shane, Matthew S; Stephen, Julia M; Jung, Rex E
2012-12-01
Despite intensive study, the role of the dorsal medial frontal cortex (dMFC) in error monitoring and conflict processing remains actively debated. The current experiment manipulated conflict type (stimulus conflict only or stimulus and response selection conflict) and utilized a novel modeling approach to isolate error and conflict variance during a multimodal numeric Stroop task. Specifically, hemodynamic response functions resulting from two statistical models that either included or isolated variance arising from relatively few error trials were directly contrasted. Twenty-four participants completed the task while undergoing event-related functional magnetic resonance imaging on a 1.5-Tesla scanner. Response times monotonically increased based on the presence of pure stimulus or stimulus and response selection conflict. Functional results indicated that dMFC activity was present during trials requiring response selection and inhibition of competing motor responses, but absent during trials involving pure stimulus conflict. A comparison of the different statistical models suggested that relatively few error trials contributed to a disproportionate amount of variance (i.e., activity) throughout the dMFC, but particularly within the rostral anterior cingulate gyrus (rACC). Finally, functional connectivity analyses indicated that an empirically derived seed in the dorsal ACC/pre-SMA exhibited strong connectivity (i.e., positive correlation) with prefrontal and inferior parietal cortex but was anti-correlated with the default-mode network. An empirically derived seed from the rACC exhibited the opposite pattern, suggesting that sub-regions of the dMFC exhibit different connectivity patterns with other large scale networks implicated in internal mentations such as daydreaming (default-mode) versus the execution of top-down attentional control (fronto-parietal). Copyright © 2011 Wiley Periodicals, Inc.
Pollock, Brad H; Elmore, Sarah; Romoser, Amelia; Tang, Lili; Kang, Min-Su; Xue, Kathy; Rodriguez, Marisa; Dierschke, Nicole A; Hayes, Holly G; Hansen, H Andrew; Guerra, Fernando; Wang, Jia-Sheng; Phillips, Timothy
2016-08-01
South Texas currently has the highest incidence of hepatocellular carcinoma (HCC) in the United States, a disease that disproportionately affects Latino populations in the region. Aflatoxin B1 (AFB1) is a potent liver carcinogen that has been shown to be present in a variety of foods in the United States, including corn and corn products. Importantly, it is a dietary risk factor contributing to a higher incidence of HCC in populations frequently consuming AFB1-contaminated diets. In a randomised double-blind placebo controlled trial, we evaluated the effects of a 3-month administration of ACCS100 (refined calcium montmorillonite clay) on serum AFB1-lysine adduct (AFB-Lys) level and serum biochemistry in 234 healthy men and women residing in Bexar and Medina counties, Texas. Participants recruited from 2012 to 2014 received either a placebo, 1.5 g or 3 g ACCS100 each day for 3 months, and no treatment during the fourth month. Adverse event rates were similar across treatment groups and no significant differences were observed for serum biochemistry and haematology parameters. Differences in levels of AFB-Lys at 1, 3 and 4 months were compared between placebo and active treatment groups. Although serum AFB-Lys levels were decreased by month 3 for both treatment groups, the low dose was the only treatment that was significant (p = 0.0005). In conclusion, the observed effect in the low-dose treatment group suggests that the use of ACCS100 may be a viable strategy to reduce dietary AFB1 bioavailability during aflatoxin outbreaks and potentially in populations chronically exposed to this carcinogen.
A functional dissociation of conflict processing within anterior cingulate cortex.
Kim, Chobok; Kroger, James K; Kim, Jeounghoon
2011-02-01
Goal-directed behavior requires cognitive control to regulate the occurrence of conflict. The dorsal anterior cingulate cortex (dACC) has been suggested in detecting response conflict during various conflict tasks. Recent findings, however, have indicated not only that two distinct subregions of dACC are involved in conflict processing but also that the conflict occurs at both perceptual and response levels. In this study, we sought to examine whether perceptual and response conflicts are functionally dissociated in dACC. Thirteen healthy subjects performed a version of the Stroop task during functional magnetic resonance imaging (fMRI) scanning. We identified a functional dissociation of the caudal dACC (cdACC) and the rostral dACC (rdACC) in their responses to different sources of conflict. The cdACC was selectively engaged in perceptual conflict whereas the rdACC was more active in response conflict. Further, the dorsolateral prefrontal cortex (DLPFC) was coactivated not with cdACC but with rdACC. We suggest that cdACC plays an important role in regulative processing of perceptual conflict whereas rdACC is involved in detecting response conflict. Copyright © 2010 Wiley-Liss, Inc.
Barkas, Fotios; Milionis, Haralampos; Kostapanos, Michael S; Mikhailidis, Dimitri P; Elisaf, Moses; Liberopoulos, Evangelos
2015-02-01
There is a paucity of data regarding the attainment of lipid-lowering treatment goals according to the recent American College of Cardiology/American Heart Association (ACC/AHA) guidelines. The aim of the present study was to assess how applicable these 2013 recommendations are in the setting of an Outpatient University Hospital Lipid Clinic. This was a retrospective (from 1999 to 2013) observational study including 1000 consecutive adults treated for hyperlipidemia and followed up for ≥3 years. Comparisons for the applicability of current European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) and recent ACC/AHA guidelines were performed. Achievement rates of low density lipoprotein cholesterol (LDL-C) targets set by ESC/EAS were 21%, 44% and 62% among patients at very high, high and moderate cardiovascular risk, respectively, receiving statin monotherapy. Among individuals on high-intensity statins only 47% achieved the anticipated ≥50% LDL-C reduction, i.e. the ACC/AHA target. The corresponding rate was significantly greater among those on statin + ezetimibe (76%, p < 0.05). Likewise, higher rates of LDL-C target attainment according to ESC/EAS guidelines were observed in patients on statin + ezetimibe compared with statin monotherapy (37, 50 and 71% for the three risk groups, p < 0.05 for the very high risk group). The application of the ACC/AHA guidelines may be associated with undertreatment of high risk patients due to suboptimal LDL-C response to high-intensity statins in clinical practice. Adding ezetimibe substantially increases the rate of the ESC/EAS LDL-C target achievement together with the rate of LDL-C lowering response suggested by the ACC/AHA.
Gresch, Paul J; Barrett, Robert J; Sanders-Bush, Elaine; Smith, Randy L
2007-02-01
d-Lysergic acid diethylamide (LSD), an indoleamine hallucinogen, produces profound alterations in mood, thought, and perception in humans. The brain site(s) that mediates the effects of LSD is currently unknown. In this study, we combine the drug discrimination paradigm with intracerebral microinjections to investigate the anatomical localization of the discriminative stimulus of LSD in rats. Based on our previous findings, we targeted the anterior cingulate cortex (ACC) to test its involvement in mediating the discriminative stimulus properties of LSD. Rats were trained to discriminate systemically administered LSD (0.085 mg/kg s.c.) from saline. Following acquisition of the discrimination, bilateral cannulae were implanted into the ACC (AP, +1.2 mm; ML, +/-1.0 mm; DV, -2.0 mm relative to bregma). Rats were tested for their ability to discriminate varying doses of locally infused LSD (0.1875, 0.375, and 0.75 microg/side) or artificial cerebrospinal fluid (n = 3-7). LSD locally infused into ACC dose-dependently substituted for systemically administered LSD, with 0.75 microg/side LSD substituting completely (89% correct). Systemic administration of the selective 5-hydroxytryptamine (serotonin) (5-HT)(2A) receptor antagonist R-(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenylethyl)]-4-piperidine-methanol (M100907; 0.4 mg/kg) blocked the discriminative cue of LSD (0.375 microg/side) infused into ACC (from 68 to 16% drug lever responding). Furthermore, M100907 (0.5 microg/microl/side) locally infused into ACC completely blocked the stimulus effects of systemic LSD (0.04 mg/kg; from 80 to 12% on the LSD lever). Taken together, these data indicate that 5-HT(2A) receptors in the ACC are a primary target mediating the discriminative stimulus properties of LSD.
Bunford, Nora; Kinney, Kerry L; Michael, Jamie; Klumpp, Heide
2017-07-03
Accumulating data from fMRI studies implicate the rostral anterior cingulate cortex (rACC) in inhibition of attention to threat distractors that compete with task-relevant goals for processing resources. However, little data is available on the reliability of rACC activation. Our aim in the current study was to examine test-retest reliability of rACC activation over a 12-week period, in the context of a validated emotional interference paradigm that varied in perceptual load. During functional MRI, 23 healthy volunteers completed a task involving a target letter in a string of identical letters (low load) or in a string of mixed letters (high load) superimposed on angry, fearful, and neutral face distractors. Intraclass correlation coefficients (ICCs) indicated that under low, but not high perceptual load, rACC activation to fearful vs. neutral distractors was moderately reliable. Conversely, regardless of perceptual load, rACC activation to angry vs. neutral distractors was not reliable. Regarding behavioral performance, ICCs indicated that accuracy was not reliable regardless of distractor type or perceptual load. Although reaction time (RT) was similarly not reliable regardless of distractor type under low perceptual load, RT to angry vs. neutral distractors and to fearful vs. neutral distractors was reliable under high perceptual load. Together, results indicate the test-retest reliability of rACC activation and corresponding behavioral performance are context dependent; reliability of the former varies as a function of distractor type and level of cognitive demand, whereas reliability of the latter depends on behavioral index (accuracy vs. RT) and level of cognitive demand but not distractor type. Copyright © 2017 Elsevier Inc. All rights reserved.
Co-occurring anxiety influences patterns of brain activity in depression.
Engels, Anna S; Heller, Wendy; Spielberg, Jeffrey M; Warren, Stacie L; Sutton, Bradley P; Banich, Marie T; Miller, Gregory A
2010-03-01
Brain activation associated with anhedonic depression and co-occurring anxious arousal and anxious apprehension was measured by fMRI during performance of an emotion word Stroop task. Consistent with EEG findings, depression was associated with rightward frontal lateralization in the dorsolateral prefrontal cortex (DLPFC), but only when anxious arousal was elevated and anxious apprehension was low. Activity in the right inferior frontal gyrus (IFG) was also reduced for depression under the same conditions. In contrast, depression was associated with more activity in the anterior cingulate cortex (dorsal ACC and rostral ACC) and the bilateral amygdala. Results imply that depression, particularly when accompanied by anxious arousal, may result in a failure to implement top-down processing by appropriate brain regions (left DLPFC, right IFG) due to increased activation in regions associated with responding to emotionally salient information (right DLPFC, amygdala).
Co-occurring Anxiety Influences Patterns of Brain Activity in Depression
Engels, Anna S.; Heller, Wendy; Spielberg, Jeffrey M.; Warren, Stacie L.; Sutton, Bradley P.; Banich, Marie T.; Miller, Gregory A.
2011-01-01
Brain activation associated with anhedonic depression and co-occurring anxious arousal and anxious apprehension was measured by fMRI during performance of an emotion-word Stroop task. Consistent with EEG findings, depression was associated with rightward frontal lateralization in dorsolateral prefrontal cortex (DLPFC), but only when anxious arousal was elevated and anxious apprehension was low. Activity in right inferior frontal gyrus (IFG) was also reduced for depression under the same conditions. In contrast, depression was associated with more activity in anterior cingulate cortex (dACC and rACC) and bilateral amygdala. Results imply that depression, particularly when accompanied by anxious arousal, may result in a failure to implement top-down processing by appropriate brain regions (left DLPFC, right IFG) due to increased activation in regions associated with responding to emotionally salient information (right DLPFC, amygdala). PMID:20233962
Chen, Bing; He, Yuan; Xia, Lei; Guo, Li-Li; Zheng, Jin-Long
2016-12-01
State-related brain structural alterations in patients with episodic tension-type headache (ETTH) are unclear. We aimed to conduct a longitudinal study to explore dynamic gray matter (GM) changes between the pain and pain-free phases in ETTH. We recruited 40 treatment-naïve ETTH patients and 40 healthy controls. All participants underwent brain structural scans on a 3.0-T MRI system. ETTH patients were scanned in and out of pain phases. Voxel-based morphometry analysis was used to determine the differences in regional gray matter density (GMD) between groups. Additional regression analysis was used to identify any associations between regional GMD and clinical symptoms. ETTH patients exhibited reduced GMD in the bilateral primary somatosensory cortex, and increased GMD in the bilateral anterior cingulate cortex (ACC) and anterior insula for the in pain phase compared with the out of pain phase. The out of pain phase of ETTH patients exhibited no regions with higher or lower GMD compared with healthy controls. GMD in the left ACC and left anterior insula was negatively correlated with headache days. GMD in the left ACC was negatively correlated with anxiety and depressive symptoms in ETTH patients. This is the first study to demonstrate dynamic and reversible GMD changes between the pain and pain-free phases in ETTH patients. However, this balance might be disrupted by increased headache days and progressive anxiety and depressive symptoms.
Neural substrates of updating the prediction through prediction error during decision making.
Wang, Ying; Ma, Ning; He, Xiaosong; Li, Nan; Wei, Zhengde; Yang, Lizhuang; Zha, Rujing; Han, Long; Li, Xiaoming; Zhang, Daren; Liu, Ying; Zhang, Xiaochu
2017-08-15
Learning of prediction error (PE), including reward PE and risk PE, is crucial for updating the prediction in reinforcement learning (RL). Neurobiological and computational models of RL have reported extensive brain activations related to PE. However, the occurrence of PE does not necessarily predict updating the prediction, e.g., in a probability-known event. Therefore, the brain regions specifically engaged in updating the prediction remain unknown. Here, we conducted two functional magnetic resonance imaging (fMRI) experiments, the probability-unknown Iowa Gambling Task (IGT) and the probability-known risk decision task (RDT). Behavioral analyses confirmed that PEs occurred in both tasks but were only used for updating the prediction in the IGT. By comparing PE-related brain activations between the two tasks, we found that the rostral anterior cingulate cortex/ventral medial prefrontal cortex (rACC/vmPFC) and the posterior cingulate cortex (PCC) activated only during the IGT and were related to both reward and risk PE. Moreover, the responses in the rACC/vmPFC and the PCC were modulated by uncertainty and were associated with reward prediction-related brain regions. Electric brain stimulation over these regions lowered the performance in the IGT but not in the RDT. Our findings of a distributed neural circuit of PE processing suggest that the rACC/vmPFC and the PCC play a key role in updating the prediction through PE processing during decision making. Copyright © 2017 Elsevier Inc. All rights reserved.
24 CFR 1000.312 - What is current assisted stock?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false What is current assisted stock... assisted stock? Current assisted stock consists of housing units owned or operated pursuant to an ACC. This includes all low rent, Mutual Help, and Turnkey III housing units under management as of September 30, 1997...
Double dissociation of value computations in orbitofrontal and anterior cingulate neurons
Kennerley, Steven W.; Behrens, Timothy E. J.; Wallis, Jonathan D.
2011-01-01
Damage to prefrontal cortex (PFC) impairs decision-making, but the underlying value computations that might cause such impairments remain unclear. Here we report that value computations are doubly dissociable within PFC neurons. While many PFC neurons encoded chosen value, they used opponent encoding schemes such that averaging the neuronal population eliminated value coding. However, a special population of neurons in anterior cingulate cortex (ACC) - but not orbitofrontal cortex (OFC) - multiplex chosen value across decision parameters using a unified encoding scheme, and encoded reward prediction errors. In contrast, neurons in OFC - but not ACC - encoded chosen value relative to the recent history of choice values. Together, these results suggest complementary valuation processes across PFC areas: OFC neurons dynamically evaluate current choices relative to recent choice values, while ACC neurons encode choice predictions and prediction errors using a common valuation currency reflecting the integration of multiple decision parameters. PMID:22037498
Rodríguez, E.; Banchio, C.; Diacovich, L.; Bibb, M. J.; Gramajo, H.
2001-01-01
Two genes, accB and accE, that form part of the same operon, were cloned from Streptomyces coelicolor A3(2). AccB is homologous to the carboxyl transferase domain of several propionyl coezyme A (CoA) carboxylases and acyl-CoA carboxylases (ACCases) of actinomycete origin, while AccE shows no significant homology to any known protein. Expression of accB and accE in Escherichia coli and subsequent in vitro reconstitution of enzyme activity in the presence of the biotinylated protein AccA1 or AccA2 confirmed that AccB was the carboxyl transferase subunit of an ACCase. The additional presence of AccE considerably enhanced the activity of the enzyme complex, suggesting that this small polypeptide is a functional component of the ACCase. The impossibility of obtaining an accB null mutant and the thiostrepton growth dependency of a tipAp accB conditional mutant confirmed that AccB is essential for S. coelicolor viability. Normal growth phenotype in the absence of the inducer was restored in the conditional mutant by the addition of exogenous long-chain fatty acids in the medium, indicating that the inducer-dependent phenotype was specifically related to a conditional block in fatty acid biosynthesis. Thus, AccB, together with AccA2, which is also an essential protein (E. Rodriguez and H. Gramajo, Microbiology 143:3109–3119, 1999), are the most likely components of an ACCase whose main physiological role is the synthesis of malonyl-CoA, the first committed step of fatty acid synthesis. Although normal growth of the conditional mutant was restored by fatty acids, the cultures did not produce actinorhodin or undecylprodigiosin, suggesting a direct participation of this enzyme complex in the supply of malonyl-CoA for the synthesis of these secondary metabolites. PMID:11526020
Greening, Steven; Norton, Loretta; Virani, Karim; Ty, Ambrose; Mitchell, Derek; Finger, Elizabeth
2014-03-01
The neural basis of individual differences in positive and negative social decisions and behaviors in healthy populations is yet undetermined. Recent work has focused on the potential role of the anterior insula in guiding social and nonsocial decision making, but the specific nature of its activation during such decision making remains unclear. To identify the neural regions mediating individual differences in helpful and harmful decisions and to assess the nature of insula activation during such decisions, in the present study we used a novel fMRI task featuring intentional and unintentional decisions to financially harm or help persons in need. Based on a whole-brain, unbiased approach, our findings indicate that individual differences in dorsal anterior insula, anterior cingulate cortex (ACC), and right temporo-parietal junction activation are associated with behavioral tendencies to financially harm or help another. Furthermore, activity in the dorsal anterior insula and ACC was greatest during unintended outcomes, whether these were gains or losses for a charity or for oneself, supporting models of the role of these regions in salience prediction error signaling. Together, the results suggest that individual differences in risk anticipation, as reflected in the dorsal anterior insula and dorsal ACC, guide social decisions to refrain from harming others.
Eryilmaz, Hamdi; Van De Ville, Dimitri; Schwartz, Sophie; Vuilleumier, Patrik
2011-02-01
The functional properties of resting brain activity are poorly understood, but have generally been related to self-monitoring and introspective processes. Here we investigated how emotionally positive and negative information differentially influenced subsequent brain activity at rest. We acquired fMRI data in 15 participants during rest periods following fearful, joyful, and neutral movies. Several brain regions were more active during resting than during movie-watching, including posterior/anterior cingulate cortices (PCC, ACC), bilateral insula and inferior parietal lobules (IPL). Functional connectivity at different frequency bands was also assessed using a wavelet correlation approach and small-world network analysis. Resting activity in ACC and insula as well as their coupling were strongly enhanced by preceding emotions, while coupling between ventral-medial prefrontal cortex and amygdala was selectively reduced. These effects were more pronounced after fearful than joyful movies for higher frequency bands. Moreover, the initial suppression of resting activity in ACC and insula after emotional stimuli was followed by a gradual restoration over time. Emotions did not affect IPL average activity but increased its connectivity with other regions. These findings reveal specific neural circuits recruited during the recovery from emotional arousal and highlight the complex functional dynamics of default mode networks in emotionally salient contexts. Copyright © 2010 Elsevier Inc. All rights reserved.
Biological and cognitive correlates of cortical curvature in schizophrenia.
Lubeiro, Alba; de Luis-García, Rodrigo; Rodríguez, Margarita; Álvarez, Aldara; de la Red, Henar; Molina, Vicente
2017-10-27
Mean cortical curvature may relate to cortico-cortical connections integrity. We explored the association between prefrontal (PFC) cortical curvature and fractional anisotropy (FA) values for tracts connecting PFC and relevant cortical regions. In schizophrenia Anatomical and diffusion magnetic resonance images were obtained from 34 patients (16 of them first-episodes) and 32 healthy controls. We calculated curvature at rostral lateral prefrontal (RLPF) and superior medial prefrontal (SMPF) areas and mean FA for the tracts respectively connecting RLPF and SMPF areas with anterior caudal cingulate (ACC), superior temporal gyrus (STG) and superior parietal SP regions. Cognitive and clinical data were collected, including baseline symptoms, Clinical Global Impression change scores from baseline to follow-up, illness duration and treatment dosage. Patients showed significantly lower FA values in the tracts linking right RLPF-ACC, right SMPF-SPG and bilaterally PFC-STG. FA values in short-range cortico-cortical connections (linking PFC and ACC) were inversely associated with PFC curvature. In patients, cognitive performance was negatively associated with PFC curvature. Larger curvature values were associated to lack of clinical improvement at follow-up. We conclude that cortical curvature is influenced by integrity in short-range cortico-cortical connections and relates to cognition and clinical outcome in schizophrenia patients. Copyright © 2017 Elsevier B.V. All rights reserved.
Sun, Jiangzhou; Chen, Qunlin; Zhang, Qinglin; Li, Yadan; Li, Haijiang; Wei, Dongtao; Yang, Wenjing; Qiu, Jiang
2016-10-01
Creativity is commonly defined as the ability to produce something both novel and useful. Stimulating creativity has great significance for both individual success and social improvement. Although increasing creative capacity has been confirmed to be possible and effective at the behavioral level, few longitudinal studies have examined the extent to which the brain function and structure underlying creativity are plastic. A cognitive stimulation (20 sessions) method was used in the present study to train subjects and to explore the neuroplasticity induced by training. The behavioral results revealed that both the originality and the fluency of divergent thinking were significantly improved by training. Furthermore, functional changes induced by training were observed in the dorsal anterior cingulate cortex (dACC), dorsal lateral prefrontal cortex (DLPFC), and posterior brain regions. Moreover, the gray matter volume (GMV) was significantly increased in the dACC after divergent thinking training. These results suggest that the enhancement of creativity may rely not only on the posterior brain regions that are related to the fundamental cognitive processes of creativity (e.g., semantic processing, generating novel associations), but also on areas that are involved in top-down cognitive control, such as the dACC and DLPFC. Hum Brain Mapp 37:3375-3387, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Plante, David T; Jensen, J Eric; Schoerning, Laura; Winkelman, John W
2012-01-01
Insomnia is closely related to major depressive disorder (MDD) both cross-sectionally and longitudinally, and as such, offers potential opportunities to refine our understanding of the neurobiology of both sleep and mood disorders. Clinical and basic science data suggest a role for reduced γ-aminobutyric acid (GABA) in both MDD and primary insomnia (PI). Here, we have utilized single-voxel proton magnetic spectroscopy (1H-MRS) at 4 Tesla to examine GABA relative to total creatine (GABA/Cr) in the occipital cortex (OC), anterior cingulate cortex (ACC), and thalamus in 20 non-medicated adults with PI (12 women) and 20 age- and sex-matched healthy sleeper comparison subjects. PI subjects had significantly lower GABA/Cr in the OC (p=0.0005) and ACC (p=0.03) compared with healthy sleepers. There was no significant difference in thalamic GABA/Cr between groups. After correction for multiple comparisons, GABA/Cr did not correlate significantly with insomnia severity measures among PI subjects. This study is the first to demonstrate regional reductions of GABA in PI in the OC and ACC. Reductions in GABA in similar brain regions in MDD using 1H-MRS suggest a common reduction in cortical GABA among PI and mood disorders. PMID:22318195
Harnett, Nathaniel G; Wood, Kimberly H; Ference, Edward W; Reid, Meredith A; Lahti, Adrienne C; Knight, Amy J; Knight, David C
2017-08-01
Trauma and stress-related disorders (e.g., Acute Stress Disorder; ASD and Post-Traumatic Stress Disorder; PTSD) that develop following a traumatic event are characterized by cognitive-affective dysfunction. The cognitive and affective functions disrupted by stress disorder are mediated, in part, by glutamatergic neural systems. However, it remains unclear whether neural glutamate concentrations, measured acutely following trauma, vary with ASD symptoms and/or future PTSD symptom expression. Therefore, the current study utilized proton magnetic resonance spectroscopy ( 1 H-MRS) to investigate glutamate/glutamine (Glx) concentrations within the dorsal anterior cingulate cortex (ACC) of recently (i.e., within one month) traumatized individuals and non-traumatized controls. Although Glx concentrations within dorsal ACC did not differ between recently traumatized and non-traumatized control groups, a positive linear relationship was observed between Glx concentrations and current stress disorder symptoms in traumatized individuals. Further, Glx concentrations showed a positive linear relationship with future stress disorder symptoms (i.e., assessed 3 months post-trauma). The present results suggest glutamate concentrations may play a role in both acute and future post-traumatic stress symptoms following a traumatic experience. The current results expand our understanding of the neurobiology of stress disorder and suggest glutamate within the dorsal ACC plays an important role in cognitive-affective dysfunction following a traumatic experience. Copyright © 2017 Elsevier Ltd. All rights reserved.
Hooker, Christine I.; Miyakawa, Asako; Verosky, Sara; Luerssen, Anna; Ayduk, Özlem N.
2012-01-01
Individuals with low self-esteem have been found to react more negatively to signs of interpersonal rejection than those with high self-esteem. However, previous research has found that individual differences in attentional control can attenuate negative reactions to social rejection among vulnerable, low self-esteem individuals. The current fMRI study sought to elucidate the neurobiological substrate of this buffering effect. We hypothesized and found that while looking at scenes of social rejection (vs negative scenes) low self-esteem high attentional control individuals engaged the rostral anterior cingulate cortex (rACC), an area of the brain associated with emotional control, more than their low self-esteem low attentional control peers. Furthermore, we found that low self-esteem high attentional control individuals evaluated social rejection as less arousing and less rejecting in a separate behavioral task. Importantly, activation in the rACC fully mediated the relationship between the interaction of self-esteem and attentional control and emotional evaluations, suggesting that the rACC activation underlies the buffering effects of attentional control. Results are discussed in terms of individual differences in emotional vulnerability and protection and by highlighting the role of rACC in emotion regulation. PMID:21609969
Auditory Conflict Resolution Correlates with Medial–Lateral Frontal Theta/Alpha Phase Synchrony
Huang, Samantha; Rossi, Stephanie; Hämäläinen, Matti; Ahveninen, Jyrki
2014-01-01
When multiple persons speak simultaneously, it may be difficult for the listener to direct attention to correct sound objects among conflicting ones. This could occur, for example, in an emergency situation in which one hears conflicting instructions and the loudest, instead of the wisest, voice prevails. Here, we used cortically-constrained oscillatory MEG/EEG estimates to examine how different brain regions, including caudal anterior cingulate (cACC) and dorsolateral prefrontal cortices (DLPFC), work together to resolve these kinds of auditory conflicts. During an auditory flanker interference task, subjects were presented with sound patterns consisting of three different voices, from three different directions (45° left, straight ahead, 45° right), sounding out either the letters “A” or “O”. They were asked to discriminate which sound was presented centrally and ignore the flanking distracters that were phonetically either congruent (50%) or incongruent (50%) with the target. Our cortical MEG/EEG oscillatory estimates demonstrated a direct relationship between performance and brain activity, showing that efficient conflict resolution, as measured with reduced conflict-induced RT lags, is predicted by theta/alpha phase coupling between cACC and right lateral frontal cortex regions intersecting the right frontal eye fields (FEF) and DLPFC, as well as by increased pre-stimulus gamma (60–110 Hz) power in the left inferior fontal cortex. Notably, cACC connectivity patterns that correlated with behavioral conflict-resolution measures were found during both the pre-stimulus and the pre-response periods. Our data provide evidence that, instead of being only transiently activated upon conflict detection, cACC is involved in sustained engagement of attentional resources required for effective sound object selection performance. PMID:25343503
Auditory conflict resolution correlates with medial-lateral frontal theta/alpha phase synchrony.
Huang, Samantha; Rossi, Stephanie; Hämäläinen, Matti; Ahveninen, Jyrki
2014-01-01
When multiple persons speak simultaneously, it may be difficult for the listener to direct attention to correct sound objects among conflicting ones. This could occur, for example, in an emergency situation in which one hears conflicting instructions and the loudest, instead of the wisest, voice prevails. Here, we used cortically-constrained oscillatory MEG/EEG estimates to examine how different brain regions, including caudal anterior cingulate (cACC) and dorsolateral prefrontal cortices (DLPFC), work together to resolve these kinds of auditory conflicts. During an auditory flanker interference task, subjects were presented with sound patterns consisting of three different voices, from three different directions (45° left, straight ahead, 45° right), sounding out either the letters "A" or "O". They were asked to discriminate which sound was presented centrally and ignore the flanking distracters that were phonetically either congruent (50%) or incongruent (50%) with the target. Our cortical MEG/EEG oscillatory estimates demonstrated a direct relationship between performance and brain activity, showing that efficient conflict resolution, as measured with reduced conflict-induced RT lags, is predicted by theta/alpha phase coupling between cACC and right lateral frontal cortex regions intersecting the right frontal eye fields (FEF) and DLPFC, as well as by increased pre-stimulus gamma (60-110 Hz) power in the left inferior fontal cortex. Notably, cACC connectivity patterns that correlated with behavioral conflict-resolution measures were found during both the pre-stimulus and the pre-response periods. Our data provide evidence that, instead of being only transiently activated upon conflict detection, cACC is involved in sustained engagement of attentional resources required for effective sound object selection performance.
Scheck, Simon M.; Pannek, Kerstin; Raffelt, David A.; Fiori, Simona; Boyd, Roslyn N.; Rose, Stephen E.
2015-01-01
In this work we investigate the structural connectivity of the anterior cingulate cortex (ACC) and its link with impaired executive function in children with unilateral cerebral palsy (UCP) due to periventricular white matter lesions. Fifty two children with UCP and 17 children with typical development participated in the study, and underwent diffusion and structural MRI. Five brain regions were identified for their high connectivity with the ACC using diffusion MRI fibre tractography: the superior frontal gyrus, medial orbitofrontal cortex, rostral middle frontal gyrus, precuneus and isthmus cingulate. Structural connectivity was assessed in pathways connecting these regions to the ACC using three diffusion MRI derived measures: fractional anisotropy (FA), mean diffusivity (MD) and apparent fibre density (AFD), and compared between participant groups. Furthermore we investigated correlations of these measures with executive function as assessed by the Flanker task. The ACC–precuneus tract had significantly different MD (p < 0.0001) and AFD (p = 0.0072) between groups, with post-hoc analysis showing significantly increased MD in the right hemisphere of children with left hemiparesis compared with controls. The ACC–superior frontal gyrus tract had significantly different FA (p = 0.0049) and MD (p = 0.0031) between groups. AFD in this tract (contralateral to side of hemiparesis; right hemisphere in controls) showed a significant relationship with Flanker task performance (p = 0.0045, β = −0.5856), suggesting that reduced connectivity correlates with executive dysfunction. Reduced structural integrity of ACC tracts appears to be important in UCP, in particular the connection to the superior frontal gyrus. Although damage to this area is heterogeneous it may be important in early identification of children with impaired executive function. PMID:26640762
Rizk, Mina M; Rubin-Falcone, Harry; Keilp, John; Miller, Jeffrey M; Sublette, M Elizabeth; Burke, Ainsley; Oquendo, Maria A; Kamal, Ahmed M; Abdelhameed, Mohamed A; Mann, J John
2017-11-01
Major depressive disorder (MDD) is associated with impaired attention control and alterations in frontal-subcortical connectivity. We hypothesized that attention control as assessed by Stroop task interference depends on white matter integrity in fronto-cingulate regions and assessed this relationship using diffusion tensor imaging (DTI) in MDD and healthy volunteers (HV). DTI images and Stroop task were acquired in 29 unmedicated MDD patients and 16 HVs, aged 18-65 years. The relationship between Stroop interference and fractional anisotropy (FA) was examined using region-of-interest (ROI) and tract-based spatial statistics (TBSS) analyses. ROI analysis revealed that Stroop interference correlated positively with FA in left caudal anterior cingulate cortex (cACC) in HVs (r = 0.62, p = 0.01), but not in MDD (r = -0.05, p= 0.79) even after controlling for depression severity. The left cACC was among 4 ROIs in fronto-cingulate network where FA was lower in MDD relative to HVs (F (1,41) = 8.87, p = 0.005). Additionally, TBSS showed the same group interaction of differences and correlations, although only at a statistical trend level. The modest sample size limits the generalizability of the findings. Structural connectivity of white matter network of cACC correlated with magnitude of Stroop interference in HVs, but not MDD. The cACC-frontal network, sub-serving attention control, may be disrupted in MDD. Less cognitive control may include enhanced effects of salience in HVs, or less effective response inhibition in MDD. Further studies of salience and inhibition components of executive function may better elucidate the relationship between brain white matter changes and executive dysfunction in MDD. Copyright © 2017 Elsevier B.V. All rights reserved.
Altered neural responses to heat pain in drug-naive patients with Parkinson disease.
Forkmann, Katarina; Grashorn, Wiebke; Schmidt, Katharina; Fründt, Odette; Buhmann, Carsten; Bingel, Ulrike
2017-08-01
Pain is a frequent but still neglected nonmotor symptom of Parkinson disease (PD). However, neural mechanisms underlying pain in PD are poorly understood. Here, we explored whether the high prevalence of pain in PD might be related to dysfunctional descending pain control. Using functional magnetic resonance imaging we explored neural responses during the anticipation and processing of heat pain in 21 PD patients (Hoehn and Yahr I-III) and 23 healthy controls (HC). Parkinson disease patients were naive to dopaminergic medication to avoid confounding drug effects. Fifteen heat pain stimuli were applied to the participants' forearm. Intensity and unpleasantness ratings were provided for each stimulus. Subjective pain perception was comparable for PD patients and HC. Neural processing, however, differed between groups: PD patients showed lower activity in several descending pain modulation regions (dorsal anterior cingulate cortex [dACC], subgenual anterior cingulate cortex, and dorsolateral prefrontal cortex [DLPFC]) and lower functional connectivity between dACC and DLPFC during pain anticipation. Parkinson disease symptom severity was negatively correlated with dACC-DLPFC connectivity indicating impaired functional coupling of pain modulatory regions with disease progression. During pain perception PD patients showed higher midcingulate cortex activity compared with HC, which also scaled with PD severity. Interestingly, dACC-DLPFC connectivity during pain anticipation was negatively associated with midcingulate cortex activity during the receipt of pain in PD patients. This study indicates altered neural processing during the anticipation and receipt of experimental pain in drug-naive PD patients. It provides first evidence for a progressive decline in descending pain modulation in PD, which might be related to the high prevalence of pain in later stages of PD.
Neural Correlates of Three Promising Endophenotypes of Depression: Evidence from the EMBARC Study
Webb, Christian A; Dillon, Daniel G; Pechtel, Pia; Goer, Franziska K; Murray, Laura; Huys, Quentin JM; Fava, Maurizio; McGrath, Patrick J; Weissman, Myrna; Parsey, Ramin; Kurian, Benji T; Adams, Phillip; Weyandt, Sarah; Trombello, Joseph M; Grannemann, Bruce; Cooper, Crystal M; Deldin, Patricia; Tenke, Craig; Trivedi, Madhukar; Bruder, Gerard; Pizzagalli, Diego A
2016-01-01
Major depressive disorder (MDD) is clinically, and likely pathophysiologically, heterogeneous. A potentially fruitful approach to parsing this heterogeneity is to focus on promising endophenotypes. Guided by the NIMH Research Domain Criteria initiative, we used source localization of scalp-recorded EEG resting data to examine the neural correlates of three emerging endophenotypes of depression: neuroticism, blunted reward learning, and cognitive control deficits. Data were drawn from the ongoing multi-site EMBARC study. We estimated intracranial current density for standard EEG frequency bands in 82 unmedicated adults with MDD, using Low-Resolution Brain Electromagnetic Tomography. Region-of-interest and whole-brain analyses tested associations between resting state EEG current density and endophenotypes of interest. Neuroticism was associated with increased resting gamma (36.5–44 Hz) current density in the ventral (subgenual) anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC). In contrast, reduced cognitive control correlated with decreased gamma activity in the left dorsolateral prefrontal cortex (dlPFC), decreased theta (6.5–8 Hz) and alpha2 (10.5–12 Hz) activity in the dorsal ACC, and increased alpha2 activity in the right dlPFC. Finally, blunted reward learning correlated with lower OFC and left dlPFC gamma activity. Computational modeling of trial-by-trial reinforcement learning further indicated that lower OFC gamma activity was linked to reduced reward sensitivity. Three putative endophenotypes of depression were found to have partially dissociable resting intracranial EEG correlates, reflecting different underlying neural dysfunctions. Overall, these findings highlight the need to parse the heterogeneity of MDD by focusing on promising endophenotypes linked to specific pathophysiological abnormalities. PMID:26068725
Increased anterior cingulate cortex response precedes behavioural adaptation in anorexia nervosa
Geisler, Daniel; Ritschel, Franziska; King, Joseph A.; Bernardoni, Fabio; Seidel, Maria; Boehm, Ilka; Runge, Franziska; Goschke, Thomas; Roessner, Veit; Smolka, Michael N.; Ehrlich, Stefan
2017-01-01
Patients with anorexia nervosa (AN) are characterised by increased self-control, cognitive rigidity and impairments in set-shifting, but the underlying neural mechanisms are poorly understood. Here we used functional magnetic resonance imaging (fMRI) to elucidate the neural correlates of behavioural adaptation to changes in reward contingencies in young acutely ill AN patients. Thirty-six adolescent/young adult, non-chronic female AN patients and 36 age-matched healthy females completed a well-established probabilistic reversal learning task during fMRI. We analysed hemodynamic responses in empirically-defined regions of interest during positive feedback and negative feedback not followed/followed by behavioural adaptation and conducted functional connectivity analyses. Although overall task performance was comparable between groups, AN showed increased shifting after receiving negative feedback (lose-shift behaviour) and altered dorsal anterior cingulate cortex (dACC) responses as a function of feedback. Specifically, patients had increased dACC responses (which correlated with perfectionism) and task-related coupling with amygdala preceding behavioural adaption. Given the generally preserved task performance in young AN, elevated dACC responses specifically during behavioural adaption is suggestive of increased monitoring for the need to adjust performance strategies. Higher dACC-amygdala coupling and increased adaptation after negative feedback underlines this interpretation and could be related to intolerance of uncertainty which has been suggested for AN. PMID:28198813
Anti-diarrhoeal investigation from aqueous extract of Cuminum cyminum Linn. Seed in Albino rats
Sahoo, Himanshu Bhusan; Sahoo, Saroj Kumar; Sarangi, Sarada Prasad; Sagar, Rakesh; Kori, Mohan Lal
2014-01-01
Background: Cuminum cyminum Linn. (Umbelliferae), commonly known as Jeera. It is native from mediterranean region, but today widely cultivated in Asian countries. It has been reported to possess various medicinal properties and an important food ingredient. The seed of the plant are claimed for treatment of diarrhoea by various traditional practitioners. Objectives: Hence, the present investigation was undertaken to evaluate aq. extract of C. cyminum seeds (ACCS) against diarrhoea on albino rats. Materials and Methods: The animals were divided into five groups and the control group was applied with 2% acacia suspension, the standard group with loperamide (3 mg/kg) or atropine sulphate (5mg/kg) and three test groups administered orally with 100, 250 and 500 mg/kg of ACCS. The antidiarrhoeal effect was investigated by castor oil induce diarrhoea model, prostaglandin E2 (PGE2) induced enteropooling model, intestinal transit by charcoal meal test. Results: The ACCS showed significant (P < 0.001) inhibition in frequency of diarrhoea, defecation time delaying, secretion of intestinal fluid as well as intestinal propulsion as compared to control and the graded doses of tested extract followed dose dependent protection against diarrhoea. Conclusions: The study reveals that the ACCS is a potent antidiarrhoeal drug which supports the traditional claim. PMID:25002800
Waring, Jill D; Etkin, Amit; Hallmayer, Joachim F; O'Hara, Ruth
2014-09-01
The serotonin transporter polymorphism short (s) allele is associated with heightened emotional reactivity and reduced emotion regulation, which increases vulnerability to depression and anxiety disorders. We investigated behavioral and neural markers of emotion regulation in community-dwelling older adults, contrasting s allele carriers and long allele homozygotes. Participants (N = 26) completed a face-word emotion conflict task during functional magnetic resonance imaging, in which facilitated regulation of emotion conflict was observed on face-word incongruent trials following another incongruent trial (i.e., emotional conflict adaptation). There were no differences between genetic groups in behavioral task performance or neural activation in postincongruent versus postcongruent trials. By contrast, connectivity between dorsal anterior cingulate cortex (ACC) and pregenual ACC, regions previously implicated in emotion conflict regulation, was impaired in s carriers for emotional conflict adaptation. This is the first demonstration of an association between serotonin transporter polymorphism and functional connectivity in older adults. Poor dorsal ACC-pregenual ACC connectivity in s carriers may be one route by which these individuals experience greater difficulty in implementing effective emotional regulation, which may contribute to their vulnerability for affective disorders. Copyright © 2014 American Association for Geriatric Psychiatry. All rights reserved.
Taren, Adrienne A; Gianaros, Peter J; Greco, Carol M; Lindsay, Emily K; Fairgrieve, April; Brown, Kirk Warren; Rosen, Rhonda K; Ferris, Jennifer L; Julson, Erica; Marsland, Anna L; Bursley, James K; Ramsburg, Jared; Creswell, J David
2015-12-01
Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Sex differences, hormones, and fMRI stress response circuitry deficits in psychoses.
Goldstein, Jill M; Lancaster, Katie; Longenecker, Julia M; Abbs, Brandon; Holsen, Laura M; Cherkerzian, Sara; Whitfield-Gabrieli, Susan; Makris, Nicolas; Tsuang, Ming T; Buka, Stephen L; Seidman, Larry J; Klibanski, Anne
2015-06-30
Response to stress is dysregulated in psychosis (PSY). fMRI studies showed hyperactivity in hypothalamus (HYPO), hippocampus (HIPP), amygdala (AMYG), anterior cingulate (ACC), orbital and medial prefrontal (OFC; mPFC) cortices, with some studies reporting sex differences. We predicted abnormal steroid hormone levels in PSY would be associated with sex differences in hyperactivity in HYPO, AMYG, and HIPP, and hypoactivity in PFC and ACC, with more severe deficits in men. We studied 32 PSY cases (50.0% women) and 39 controls (43.6% women) using a novel visual stress challenge while collecting blood. PSY males showed BOLD hyperactivity across all hypothesized regions, including HYPO and ACC by FWE-correction. Females showed hyperactivity in HIPP and AMYG and hypoactivity in OFC and mPFC, the latter FWE-corrected. Interaction of group by sex was significant in mPFC (F = 7.00, p = 0.01), with PSY females exhibiting the lowest activity. Male hyperactivity in HYPO and ACC was significantly associated with hypercortisolemia post-stress challenge, and mPFC with low androgens. Steroid hormones and neural activity were dissociated in PSY women. Findings suggest disruptions in neural circuitry-hormone associations in response to stress are sex-dependent in psychosis, particularly in prefrontal cortex. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Saito, Yukiko; Kubicki, Marek; Koerte, Inga; Otsuka, Tatsui; Rathi, Yogesh; Pasternak, Ofer; Bouix, Sylvain; Eckbo, Ryan; Kikinis, Zora; von Hohenberg, Christian Clemm; Roppongi, Tomohide; Del Re, Elisabetta; Asami, Takeshi; Lee, Sang-Hyuk; Karmacharya, Sarina; Mesholam-Gately, Raquelle I; Seidman, Larry J; Levitt, James; McCarley, Robert W; Shenton, Martha E; Niznikiewicz, Margaret A
2018-02-01
In schizophrenia, abnormalities in structural connectivity between brain regions known to contain mirror neurons and their relationship to negative symptoms related to a domain of social cognition are not well understood. Diffusion tensor imaging (DTI) scans were acquired in 16 patients with first episode schizophrenia and 16 matched healthy controls. FA and Trace of the tracts interconnecting regions known to be rich in mirror neurons, i.e., anterior cingulate cortex (ACC), inferior parietal lobe (IPL) and premotor cortex (PMC) were evaluated. A significant group effect for Trace was observed in IPL-PMC white matter fiber tract (F (1, 28) = 7.13, p = .012), as well as in the PMC-ACC white matter fiber tract (F (1, 28) = 4.64, p = .040). There were no group differences in FA. In addition, patients with schizophrenia showed a significant positive correlation between the Trace of the left IPL-PMC white matter fiber tract, and the Ability to Feel Intimacy and Closeness score (rho = .57, p = 0.034), and a negative correlation between the Trace of the left PMC-ACC and the Relationships with Friends and Peers score (rho = remove -.54, p = 0.049). We have demonstrated disrupted white mater microstructure within the white matter tracts subserving brain regions containing mirror neurons. We further showed that such structural disruptions might impact negative symptoms and, more specifically, contribute to the inability to feel intimacy (a measure conceptually related to theory of mind) in first episode schizophrenia. Further studies are needed to understand the potential of our results for diagnosis, prognosis and therapeutic interventions.
McCright, Aaron M; Charters, Meghan; Dentzman, Katherine; Dietz, Thomas
2016-01-01
Prior research on the influence of various ways of framing anthropogenic climate change (ACC) do not account for the organized ACC denial in the U.S. media and popular culture, and thus may overestimate these frames' influence in the general public. We conducted an experiment to examine how Americans' ACC views are influenced by four promising frames for urging action on ACC (economic opportunity, national security, Christian stewardship, and public health)-when these frames appear with an ACC denial counter-frame. This is the first direct test of how exposure to an ACC denial message influences Americans' ACC views. Overall, these four positive frames have little to no effect on ACC beliefs. But exposure to an ACC denial counter-frame does significantly reduce respondents' belief in the reality of ACC, belief about the veracity of climate science, awareness of the consequences of ACC, and support for aggressively attempting to reduce our nation's GHG emissions in the near future. Furthermore, as expected by the Anti-Reflexivity Thesis, exposure to the ACC denial counter-frame has a disproportionate influence on the ACC views of conservatives (than on those of moderates and liberals), effectively activating conservatives' underlying propensity for anti-reflexivity. Copyright © 2015 Cognitive Science Society, Inc.
Disrupted Prefrontal Activity during Emotion Processing in Complicated Grief: an fMRI Investigation
Arizmendi, Brian; Kaszniak, Alfred W.; O’Connor, Mary-Frances
2015-01-01
Complicated Grief, marked by a persistent and intrusive grief lasting beyond the expected period of adaptation, is associated with a relative inability to disengage from idiographic loss-relevant stimuli (O’Connor & Arizmendi, 2014). In other populations, functional magnetic resonance imaging (fMRI) studies investigating the neural networks associated with this bias consistently implicate the anterior cingulate cortex (ACC) during emotion regulation. In the present study, twenty-eight older adults were categorized into three groups based on grief severity: Complicated Grief (n=8), Non-Complicated Grief (n=9), and Nonbereaved, married controls (n=11). Using a block design, all participants completed 8 blocks (20 stimuli per block) of the ecStroop task during fMRI data acquisition. Differences in neural activity during grief-related (as opposed to neutral) stimuli across groups were examined. Those with Complicated Grief showed an absence of increased rostral ACC (rACC) and fronto-cortical recruitment relative to Nonbereaved controls. Activity in the orbitofrontal cortex (x=6, y=54, z=−10) was significantly elevated in the Non-Complicated Grief group when compared to Nonbereaved controls. Post hoc analysis evidenced activity in the dorsal ACC in the Complicated Grief and Nonbereaved groups late in the task. These findings, supported by behavioral data, suggest a relative inability to recruit the regions necessary for successful completion of this emotional task in those with Complicated Grief. This deficit was not observed in recruitment of the orbitofrontal cortex and the rACC during processing of idiographic semantic stimuli in Non-Complicated Grief. PMID:26434802
Disrupted prefrontal activity during emotion processing in complicated grief: An fMRI investigation.
Arizmendi, Brian; Kaszniak, Alfred W; O'Connor, Mary-Frances
2016-01-01
Complicated Grief, marked by a persistent and intrusive grief lasting beyond the expected period of adaptation, is associated with a relative inability to disengage from idiographic loss-relevant stimuli (O'Connor and Arizmendi, 2014). In other populations, functional magnetic resonance imaging (fMRI) studies investigating the neural networks associated with this bias consistently implicate the anterior cingulate cortex (ACC) during emotion regulation. In the present study, twenty-eight older adults were categorized into three groups based on grief severity: Complicated Grief (n=8), Non-Complicated Grief (n=9), and Nonbereaved, married controls (n=11). Using a block design, all participants completed 8 blocks (20 stimuli per block) of the ecStroop task during fMRI data acquisition. Differences in neural activity during grief-related (as opposed to neutral) stimuli across groups were examined. Those with Complicated Grief showed an absence of increased rostral ACC (rACC) and fronto-cortical recruitment relative to Nonbereaved controls. Activity in the orbitofrontal cortex (x=6, y=54, z=-10) was significantly elevated in the Non-Complicated Grief group when compared to Nonbereaved controls. Post hoc analysis evidenced activity in the dorsal ACC in the Complicated Grief and Nonbereaved groups late in the task. These findings, supported by behavioral data, suggest a relative inability to recruit the regions necessary for successful completion of this emotional task in those with Complicated Grief. This deficit was not observed in recruitment of the orbitofrontal cortex and the rACC during processing of idiographic semantic stimuli in Non-Complicated Grief. Copyright © 2015 Elsevier Inc. All rights reserved.
From Threat to Fear: The neural organization of defensive fear systems in humans
Mobbs, Dean; Marchant, Jennifer L; Hassabis, Demis; Seymour, Ben; Tan, Geoffrey; Gray, Marcus; Petrovic, Predrag; Dolan, Raymond J.; Frith, Christopher D.
2009-01-01
Post-encounter and circa-strike defensive contexts represent two adaptive responses to potential and imminent danger. In the context of a predator, the post-encounter reflects the initial detection of the potential threat, whilst the circa-strike is associated with direct predatory attack. We used fMRI to investigate the neural organization of anticipation and avoidance of artificial predators with high or low probability of capturing the subject across analogous post-encounter and circa-strike contexts of threat. Consistent with defense systems models, post-encounter threat elicited activity in forebrain areas including subgenual anterior cingulate cortex (sgACC), hippocampus and amygdala. Conversely, active avoidance during circa-strike threat increased activity in mid-dorsal ACC and midbrain areas. During the circa-strike condition, subjects showed increased coupling between the midbrain and mid-dorsal ACC and decreased coupling with the sgACC, amygdala and hippocampus. Greater activity was observed in the right pregenual ACC for high compared to low probability of capture during circa-strike threat. This region showed decreased coupling with the amygdala, insula and ventromedial prefrontal cortex. Finally, we found that locomotor errors correlated with subjective reports of panic for the high compared to low probability of capture during the circa-strike threat and these panic-related locomotor errors were correlated with midbrain activity. These findings support models suggesting that higher forebrain areas are involved in early threat responses, including the assignment and control of fear, whereas as imminent danger results in fast, likely “hard-wired”, defensive reactions mediated by the midbrain. PMID:19793982
Dissociable Frontal Controls during Visible and Memory-guided Eye-Tracking of Moving Targets
Ding, Jinhong; Powell, David; Jiang, Yang
2009-01-01
When tracking visible or occluded moving targets, several frontal regions including the frontal eye fields (FEF), dorsal-lateral prefrontal cortex (DLPFC), and Anterior Cingulate Cortex (ACC) are involved in smooth pursuit eye movements (SPEM). To investigate how these areas play different roles in predicting future locations of moving targets, twelve healthy college students participated in a smooth pursuit task of visual and occluded targets. Their eye movements and brain responses measured by event-related functional MRI were simultaneously recorded. Our results show that different visual cues resulted in time discrepancies between physical and estimated pursuit time only when the moving dot was occluded. Visible phase velocity gain was higher than that of occlusion phase. We found bilateral FEF association with eye-movement whether moving targets are visible or occluded. However, the DLPFC and ACC showed increased activity when tracking and predicting locations of occluded moving targets, and were suppressed during smooth pursuit of visible targets. When visual cues were increasingly available, less activation in the DLPFC and the ACC was observed. Additionally, there was a significant hemisphere effect in DLPFC, where right DLPFC showed significantly increased responses over left when pursuing occluded moving targets. Correlation results revealed that DLPFC, the right DLPFC in particular, communicates more with FEF during tracking of occluded moving targets (from memory). The ACC modulates FEF more during tracking of visible targets (likely related to visual attention). Our results suggest that DLPFC and ACC modulate FEF and cortical networks differentially during visible and memory-guided eye tracking of moving targets. PMID:19434603
Tuning the Brake While Raising the Stake: Network Dynamics during Sequential Decision-Making.
Meder, David; Haagensen, Brian Numelin; Hulme, Oliver; Morville, Tobias; Gelskov, Sofie; Herz, Damian Marc; Diomsina, Beata; Christensen, Mark Schram; Madsen, Kristoffer Hougaard; Siebner, Hartwig Roman
2016-05-11
When gathering valued goods, risk and reward are often coupled and escalate over time, for instance, during foraging, trading, or gambling. This escalating frame requires agents to continuously balance expectations of reward against those of risk. To address how the human brain dynamically computes these tradeoffs, we performed whole-brain fMRI while healthy young individuals engaged in a sequential gambling task. Participants were repeatedly confronted with the option to continue with throwing a die to accumulate monetary reward under escalating risk, or the alternative option to stop to bank the current balance. Within each gambling round, the accumulation of gains gradually increased reaction times for "continue" choices, indicating growing uncertainty in the decision to continue. Neural activity evoked by "continue" choices was associated with growing activity and connectivity of a cortico-subcortical "braking" network that positively scaled with the accumulated gains, including pre-supplementary motor area (pre-SMA), inferior frontal gyrus, caudate, and subthalamic nucleus (STN). The influence of the STN on continue-evoked activity in the pre-SMA was predicted by interindividual differences in risk-aversion attitudes expressed during the gambling task. Furthermore, activity in dorsal anterior cingulate cortex (ACC) reflected individual choice tendencies by showing increased activation when subjects made nondefault "continue" choices despite an increasing tendency to stop, but ACC activity did not change in proportion with subjective choice uncertainty. Together, the results implicate a key role of dorsal ACC, pre-SMA, inferior frontal gyrus, and STN in computing the trade-off between escalating reward and risk in sequential decision-making. Using a paradigm where subjects experienced increasing potential rewards coupled with increasing risk, this study addressed two unresolved questions in the field of decision-making: First, we investigated an "inhibitory" network of regions that has so far been investigated with externally cued action inhibition. In this study, we show that the dynamics in this network under increasingly risky decisions are predictive of subjects' risk attitudes. Second, we contribute to a currently ongoing debate about the anterior cingulate cortex's role in sequential foraging decisions by showing that its activity is related to making nondefault choices rather than to choice uncertainty. Copyright © 2016 Meder, Haagensen, et al.
Functional connectivity patterns reflect individual differences in conflict adaptation.
Wang, Xiangpeng; Wang, Ting; Chen, Zhencai; Hitchman, Glenn; Liu, Yijun; Chen, Antao
2015-04-01
Individuals differ in the ability to utilize previous conflict information to optimize current conflict resolution, which is termed the conflict adaptation effect. Previous studies have linked individual differences in conflict adaptation to distinct brain regions. However, the network-based neural mechanisms subserving the individual differences of the conflict adaptation effect have not been studied. The present study employed a psychophysiological interaction (PPI) analysis with a color-naming Stroop task to examine this issue. The main results were as follows: (1) the anterior cingulate cortex (ACC)-seeded PPI revealed the involvement of the salience network (SN) in conflict adaptation, while the posterior parietal cortex (PPC)-seeded PPI revealed the engagement of the central executive network (CEN). (2) Participants with high conflict adaptation effect showed higher intra-CEN connectivity and lower intra-SN connectivity; while those with low conflict adaptation effect showed higher intra-SN connectivity and lower intra-CEN connectivity. (3) The PPC-centered intra-CEN connectivity positively predicted the conflict adaptation effect; while the ACC-centered intra-SN connectivity had a negative correlation with this effect. In conclusion, our data demonstrated that conflict adaptation is likely supported by the CEN and the SN, providing a new perspective on studying individual differences in conflict adaptation on the basis of large-scale networks. Copyright © 2015 Elsevier Ltd. All rights reserved.
Altered thalamo-cortical resting state functional connectivity in smokers.
Wang, Chaoyan; Bai, Jie; Wang, Caihong; von Deneen, Karen M; Yuan, Kai; Cheng, Jingliang
2017-07-13
The thalamus has widespread connections with the prefrontal cortex (PFC) and modulates communication between the striatum and PFC, which is crucial to the neural mechanisms of smoking. However, relatively few studies focused on the thalamic resting state functional connectivity (RSFC) patterns and their association with smoking behaviors in smokers. 24 young male smokers and 24 non-smokers were enrolled in our study. Fagerström Test for Nicotine Dependence (FTND) was used to assess the nicotine dependence level. The bilateral thalamic RSFC patterns were compared between smokers and non-smokers. The relationship between neuroimaging findings and smoking behaviors (FTND and pack-years) were also investigated in smokers. Relative to nonsmokers, smokers showed reduced RSFC strength between the left thalamus and several brain regions, i.e. the right dorsolateral prefrontal cortex (dlPFC), the anterior cingulate cortex (ACC) and the bilateral caudate. In addition, the right thalamus showed reduced RSFC with the right dlPFC as well as the bilateral insula in smokers. Therefore, the findings in the current study revealed the reduced RSFC of the thalamus with the dlPFC, the ACC, the insula and the caudate in smokers, which provided new insights into the roles of the thalamus in nicotine addiction from a function integration perspective. Copyright © 2017 Elsevier B.V. All rights reserved.
Xian, Mingjie; Zhai, Lei; Zhong, Naiqin; Ma, Yiwei; Xue, Yanfen; Ma, Yanhe
2013-08-04
Acetyl-CoA carboxylase (ACC) catalyzes the first step of fatty acid synthesis. In most bacteria, ACC is composed of four subunits encoded by accA, accB, accC, and accD. Of them, accA encodes acetyl-CoA carboxyltransferase alpha-subunit. Our prior work on proteomics of Alkalimonas amylolytica N10 showed that the expression of the Aa-accA has a remarkable response to salt and alkali stress. This research aimed to find out the Aa-accA gene contributing to salt and alkali tolerance. The Aa-accA was amplified by PCR from A. amylolytica N10 and expressed in E. coli K12 host. The effects of Aa-accA expression on the growth of transgenic strains were examined under different NaCl concentration and pH conditions. Transgenic tobacco BY-2 cells harboring Aa-accA were also generated via Agrobacterium-mediated transformation. The viability of BY-2 cells was determined with FDA staining method after salt and alkali shock. The Aa-accA gene product has 318 amino acids and is homologous to the carboxyl transferase domain of acyl-CoA carboxylases. It showed 76% identity with AccA (acetyl-CoA carboxylase carboxyltransferase subunit alpha) from E. coli. Compared to the wild-type strains, transgenic E. coli K12 strain containing Aa-accA showed remarkable growth superiority when grown in increased NaCl concentrations and pH levels. The final cell density of the transgenic strains was 2.6 and 3.5 times higher than that of the control type when they were cultivated in LB medium containing 6% (W/V) NaCl and at pH 9, respectively. Complementary expression of Aa-accA in an accA-depletion E. coli can recover the tolerance of K12 delta accA to salt and alkali stresses to some extent. Similar to the transgenic E. coli, transgenic tobacco BY-2 cells showed higher percentages of viability compared to the wild BY-2 cells under the salt or alkali stress condition. We found that Aa-accA from A. amylolytica N10 overexpression enhances the tolerance of both transgenic E. coli and tobacco BY-2 cells to NaCl and alkali stresses.
Bengtson Nash, Susan; Rintoul, Stephen R; Kawaguchi, So; Staniland, Iain; van den Hoff, John; Tierney, Megan; Bossi, Rossana
2010-09-01
In order to investigate the extent to which Perfluorinated Contaminants (PFCs) have permeated the Southern Ocean food web to date, a range of Antarctic, sub-Antarctic and Antarctic-migratory biota were analysed for key ionic PFCs. Based upon the geographical distribution pattern and ecology of biota with detectable vs. non-detectable PFC burdens, an evaluation of the potential contributory roles of alternative system input pathways is made. Our analytical findings, together with previous reports, reveal only the occasional occurrence of PFCs in migratory biota and vertebrate predators with foraging ranges extending into or north of the Antarctic Circumpolar Current (ACC). Geographical contamination patterns observed correspond most strongly with those expected from delivery via hydrospheric transport as governed by the unique oceanographic features of the Southern Ocean. We suggest that hydrospheric transport will form a slow, but primary, input pathway of PFCs to the Antarctic region. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
Transformation and crystallization energetics of synthetic and biogenic amorphous calcium carbonate.
Radha, A V; Forbes, Tori Z; Killian, Christopher E; Gilbert, P U P A; Navrotsky, Alexandra
2010-09-21
Amorphous calcium carbonate (ACC) is a metastable phase often observed during low temperature inorganic synthesis and biomineralization. ACC transforms with aging or heating into a less hydrated form, and with time crystallizes to calcite or aragonite. The energetics of transformation and crystallization of synthetic and biogenic (extracted from California purple sea urchin larval spicules, Strongylocentrotus purpuratus) ACC were studied using isothermal acid solution calorimetry and differential scanning calorimetry. Transformation and crystallization of ACC can follow an energetically downhill sequence: more metastable hydrated ACC → less metastable hydrated ACC ⇒ anhydrous ACC ∼ biogenic anhydrous ACC ⇒ vaterite → aragonite → calcite. In a given reaction sequence, not all these phases need to occur. The transformations involve a series of ordering, dehydration, and crystallization processes, each lowering the enthalpy (and free energy) of the system, with crystallization of the dehydrated amorphous material lowering the enthalpy the most. ACC is much more metastable with respect to calcite than the crystalline polymorphs vaterite or aragonite. The anhydrous ACC is less metastable than the hydrated, implying that the structural reorganization during dehydration is exothermic and irreversible. Dehydrated synthetic and anhydrous biogenic ACC are similar in enthalpy. The transformation sequence observed in biomineralization could be mainly energetically driven; the first phase deposited is hydrated ACC, which then converts to anhydrous ACC, and finally crystallizes to calcite. The initial formation of ACC may be a first step in the precipitation of calcite under a wide variety of conditions, including geological CO(2) sequestration.
Dynamics of Autotrophic Marine Planktonic Thaumarchaeota in the East China Sea
Hu, Anyi; Yang, Zao; Yu, Chang-Ping; Jiao, Nianzhi
2013-01-01
The ubiquitous and abundant distribution of ammonia-oxidizing Thaumarchaeota in marine environments is now well documented, and their crucial role in the global nitrogen cycle has been highlighted. However, the potential contribution of Thaumarchaeota in the carbon cycle remains poorly understood. Here we present for the first time a seasonal investigation on the shelf region (bathymetry≤200 m) of the East China Sea (ECS) involving analysis of both thaumarchaeal 16S rRNA and autotrophy-related genes (acetyl-CoA carboxylase gene, accA). Quantitative PCR results clearly showed a higher abundance of thaumarchaeal 16S and accA genes in late-autumn (November) than summer (August), whereas the diversity and community structure of autotrophic Thaumarchaeota showed no statistically significant difference between different seasons as revealed by thaumarchaeal accA gene clone libraries. Phylogenetic analysis indicated that shallow ecotypes dominated the autotrophic Thaumarchaeota in the ECS shelf (86.3% of total sequences), while a novel non-marine thaumarchaeal accA lineage was identified in the Changjiang estuary in summer (when freshwater plumes become larger) but not in autumn, implying that Changjiang freshwater discharge played a certain role in transporting terrestrial microorganisms to the ECS. Multivariate statistical analysis indicated that the biogeography of the autotrophic Thaumarchaeota in the shelf water of the ECS was influenced by complex hydrographic conditions. However, an in silico comparative analysis suggested that the diversity and abundance of the autotrophic Thaumarchaeota might be biased by the ‘universal’ thaumarchaeal accA gene primers Cren529F/Cren981R since this primer set is likely to miss some members within particular phylogenetic groups. Collectively, this study improved our understanding of the biogeographic patterns of the autotrophic Thaumarchaeota in temperate coastal waters, and suggested that new accA primers with improved coverage and sensitivity across phylogenetic groups are needed to gain a more thorough understanding of the role of the autotrophic Thaumarchaeota in the global carbon cycle. PMID:23565298
Jansen, Maria W J; van Oers, Hans A M; Middelweerd, Mizzi D R; van de Goor, Ien A M; Ruwaard, Dirk
2015-08-21
Contemporary research should increasingly be carried out in the context of application. Nowotny called this new form of knowledge production Mode-2. In line with Mode-2 knowledge production, the Dutch government in 2006 initiated the so-called Academic Collaborative Centres (ACC) for Public Health. The aim of these ACCs is to build a regional, sustainable knowledge-sharing network to deliver socially robust knowledge. The present study aims to highlight the enabling and constraining push and pull factors of these ACCs in order to assess whether the ACCs are able to build and strengthen a sustainable integrated organizational network between public health policy, practice, and research. Our empirical analysis builds on a mixed methods design. Quantitative data was derived from records of a survey sent to all 11 ACCs about personnel investments, number and nature of projects, and earning power. Qualitative data was derived from 21 in-depth interviews with stakeholders involved. The interviews were tape-recorded, transcribed, and manually coded as favourable or unfavourable pull or push factors. The extra funding appeared to be the most enabling push factor. The networks secured external grants for about 150 short- and long-term Mode-2 knowledge production projects in the past years. Enabling pull factors improved, especially the number of policy-driven short-term research projects. Exchange agents were able to constructively deal with the constraining push factors, like university's publication pressure and budget limitations. However, the constraining pull factors like local government's involvement and their low demand for scientific evidence were difficult to overcome. A clear improvement of the organizational networks was noticed whereby the ACC's were pushed rather than pulled. Efforts are needed to increase the demand for scientific and socially robust evidence from policymakers and to resolve the regime differences between the research and policy systems, in order to make the bidirectionality of the links sustainable.
Dynamics of autotrophic marine planktonic thaumarchaeota in the East China Sea.
Hu, Anyi; Yang, Zao; Yu, Chang-Ping; Jiao, Nianzhi
2013-01-01
The ubiquitous and abundant distribution of ammonia-oxidizing Thaumarchaeota in marine environments is now well documented, and their crucial role in the global nitrogen cycle has been highlighted. However, the potential contribution of Thaumarchaeota in the carbon cycle remains poorly understood. Here we present for the first time a seasonal investigation on the shelf region (bathymetry≤200 m) of the East China Sea (ECS) involving analysis of both thaumarchaeal 16S rRNA and autotrophy-related genes (acetyl-CoA carboxylase gene, accA). Quantitative PCR results clearly showed a higher abundance of thaumarchaeal 16S and accA genes in late-autumn (November) than summer (August), whereas the diversity and community structure of autotrophic Thaumarchaeota showed no statistically significant difference between different seasons as revealed by thaumarchaeal accA gene clone libraries. Phylogenetic analysis indicated that shallow ecotypes dominated the autotrophic Thaumarchaeota in the ECS shelf (86.3% of total sequences), while a novel non-marine thaumarchaeal accA lineage was identified in the Changjiang estuary in summer (when freshwater plumes become larger) but not in autumn, implying that Changjiang freshwater discharge played a certain role in transporting terrestrial microorganisms to the ECS. Multivariate statistical analysis indicated that the biogeography of the autotrophic Thaumarchaeota in the shelf water of the ECS was influenced by complex hydrographic conditions. However, an in silico comparative analysis suggested that the diversity and abundance of the autotrophic Thaumarchaeota might be biased by the 'universal' thaumarchaeal accA gene primers Cren529F/Cren981R since this primer set is likely to miss some members within particular phylogenetic groups. Collectively, this study improved our understanding of the biogeographic patterns of the autotrophic Thaumarchaeota in temperate coastal waters, and suggested that new accA primers with improved coverage and sensitivity across phylogenetic groups are needed to gain a more thorough understanding of the role of the autotrophic Thaumarchaeota in the global carbon cycle.
Perry, Jennifer L.; Joseph, Jane E.; Jiang, Yang; Zimmerman, Rick S.; Kelly, Thomas H.; Darna, Mahesh; Huettl, Peter; Dwoskin, Linda P.; Bardo, Michael T.
2010-01-01
Vulnerability to drug abuse is related to both reward seeking and impulsivity, two constructs thought to have a biological basis in the prefrontal cortex (PFC). This review addresses similarities and differences in neuroanatomy, neurochemistry and behavior associated with PFC function in rodents and primates. Emphasis is placed on monoamine and amino acid neurotransmitter systems located in anatomically distinct subregions: medial prefrontal cortex (mPFC); lateral prefrontal cortex (lPFC); anterior cingulate cortex (ACC); and orbitofrontal cortex (OFC). While there are complex interconnections and overlapping functions among these regions, each is thought to be involved in various functions related to health-related risk behaviors and drug abuse vulnerability. Among the various functions implicated, evidence suggests that mPFC is involved in reward processing, attention and drug reinstatement; lPFC is involved in decision-making, behavioral inhibition and attentional gating; ACC is involved in attention, emotional processing and self-monitoring; and OFC is involved in behavioral inhibition, signaling of expected outcomes and reward/punishment sensitivity. Individual differences factors (e.g., age and sex) influence functioning of these regions, which, in turn, impacts drug abuse vulnerability. Implications for the development of drug abuse prevention and treatment strategies aimed at engaging PFC inhibitory processes that may reduce risk-related behaviors are discussed, including the design of effective public service announcements, cognitive exercises, physical activity, direct current stimulation, feedback control training and pharmacotherapies. A major challenge in drug abuse prevention and treatment rests with improving intervention strategies aimed at strengthening PFC inhibitory systems among at-risk individuals. PMID:20837060
Walczak, Adam; Ahlstrom, Jayne; Denslow, Stewart; Horwitz, Amy; Dubno, Judy R.
2008-01-01
Speech recognition can be difficult and effortful for older adults, even for those with normal hearing. Declining frontal lobe cognitive control has been hypothesized to cause age-related speech recognition problems. This study examined age-related changes in frontal lobe function for 15 clinically normal hearing adults (21–75 years) when they performed a word recognition task that was made challenging by decreasing word intelligibility. Although there were no age-related changes in word recognition, there were age-related changes in the degree of activity within left middle frontal gyrus (MFG) and anterior cingulate (ACC) regions during word recognition. Older adults engaged left MFG and ACC regions when words were most intelligible compared to younger adults who engaged these regions when words were least intelligible. Declining gray matter volume within temporal lobe regions responsive to word intelligibility significantly predicted left MFG activity, even after controlling for total gray matter volume, suggesting that declining structural integrity of brain regions responsive to speech leads to the recruitment of frontal regions when words are easily understood. Electronic supplementary material The online version of this article (doi:10.1007/s10162-008-0113-3) contains supplementary material, which is available to authorized users. PMID:18274825
Salami, Alireza; Rieckmann, Anna; Fischer, Håkan; Bäckman, Lars
2014-02-01
Functional neuroimaging studies demonstrate age-related differences in recruitment of a large-scale attentional network during interference resolution, especially within dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC). These alterations in functional responses have been frequently observed despite equivalent task performance, suggesting age-related reallocation of neural resources, although direct evidence for a facilitating effect in aging is sparse. We used the multi-source interference task and multivariate partial-least-squares to investigate age-related differences in the neuronal signature of conflict resolution, and their behavioral implications in younger and older adults. There were interference-related increases in activity, involving fronto-parietal and basal ganglia networks that generalized across age. In addition an age-by-task interaction was observed within a distributed network, including DLPFC and ACC, with greater activity during interference in the old. Next, we combined brain-behavior and functional connectivity analyses to investigate whether compensatory brain changes were present in older adults, using DLPFC and ACC as regions of interest (i.e. seed regions). This analysis revealed two networks differentially related to performance across age groups. A structural analysis revealed age-related gray-matter losses in regions facilitating performance in the young, suggesting that functional reorganization may partly reflect structural alterations in aging. Collectively, these findings suggest that age-related structural changes contribute to reductions in the efficient recruitment of a youth-like interference network, which cascades into instantiation of a different network facilitating conflict resolution in elderly people. © 2013. Published by Elsevier Inc. All rights reserved.
Differentiating between bipolar and unipolar depression in functional and structural MRI studies.
Han, Kyu-Man; De Berardis, Domenico; Fornaro, Michele; Kim, Yong-Ku
2018-03-28
Distinguishing depression in bipolar disorder (BD) from unipolar depression (UD) solely based on clinical clues is difficult, which has led to the exploration of promising neural markers in neuroimaging measures for discriminating between BD depression and UD. In this article, we review structural and functional magnetic resonance imaging (MRI) studies that directly compare UD and BD depression based on neuroimaging modalities including functional MRI studies on regional brain activation or functional connectivity, structural MRI on gray or white matter morphology, and pattern classification analyses using a machine learning approach. Numerous studies have reported distinct functional and structural alterations in emotion- or reward-processing neural circuits between BD depression and UD. Different activation patterns in neural networks including the amygdala, anterior cingulate cortex (ACC), prefrontal cortex (PFC), and striatum during emotion-, reward-, or cognition-related tasks have been reported between BD and UD. A stronger functional connectivity pattern in BD was pronounced in default mode and in frontoparietal networks and brain regions including the PFC, ACC, parietal and temporal regions, and thalamus compared to UD. Gray matter volume differences in the ACC, hippocampus, amygdala, and dorsolateral prefrontal cortex (DLPFC) have been reported between BD and UD, along with a thinner DLPFC in BD compared to UD. BD showed reduced integrity in the anterior part of the corpus callosum and posterior cingulum compared to UD. Several studies performed pattern classification analysis using structural and functional MRI data to distinguish between UD and BD depression using a supervised machine learning approach, which yielded a moderate level of accuracy in classification. Copyright © 2018 Elsevier Inc. All rights reserved.
Griffiths, D.; Tadic, S.D.; Schaefer, W.; Resnick, N.M.
2009-01-01
Loss of bladder control (urge incontinence) is common in elderly; the cause is usually unknown. Functional imaging has revealed the brain network controlling responses to bladder filling. Age-related changes in this network might predispose to urge incontinence. We sought such changes in 10 continent, healthy women aged 30 – 79 years who underwent fMRI while fluid (20 ml) was repeatedly infused into and withdrawn from the bladder. Data were collected in 4 measurement blocks with progressively increasing bladder volumes and were analyzed by SPM2, using the contrast infuse-withdraw to quantify response to bladder infusion. Effective connectivity was examined by physiophysiological interaction (PhPI; see interpretation in Supplementary Material), with right insula (RI) and dorsal anterior cingulate cortex (dACC) as seed regions. Dependence on age and bladder volume (=block number) was assessed. Bladder infusion evoked expected activations. Activation decreased with age in bilateral insula and dACC. PhPI revealed connectivity with RI and dACC in regions that included bilateral putamen and R pontine micturition center. Interaction (connectivity) tended to increase with age in regions including L insula, L paracentral lobule and PAG. Consistent with a special role in maintaining continence, medial prefrontal cortex (mPFC) showed a trend to deactivation on bladder infusion that became more prominent in old age, and a trend to negative interaction (connectivity) that weakened significantly with age. Thus, with increasing age, weaker signals in the bladder control network as a whole and/or changes in mPFC function or connecting pathways may be responsible for the development of urge incontinence. PMID:19427909
Individual Differences in Risk Preference Predict Neural Responses during Financial Decision-Making
Engelmann, Jan B.; Tamir, Diana
2009-01-01
We investigated the neural correlates of subjective valuations during a task involving risky choices about lotteries. Because expected value was held constant across all lotteries, decisions were influenced by subjective preferences, which manifest behaviorally as risk-seeking or risk-averse attitudes. To isolate structures encoding risk preference during choice, we probed for areas showing increased activation as a function of selected risk-level. Such response patterns were obtained in anterior (ACC) and posterior cingulate cortex (PCC), superior frontal gyrus, caudate nucleus, and substantia nigra. Behavioral results revealed the presence of risk-averse and risk-neutral individuals. In parallel, brain signals revealed modulation of activity by risk-attitude during choice. Correlations between risk-seeking attitudes and neural activity during risky choice were obtained in superior and inferior frontal gyri, medial and lateral orbitofrontal cortex, and parahippocampal gyrus, while correlations with risk-averse attitudes were found in the caudate. The dynamics of neural responses relevant to each stage of the task (decision, anticipation, outcome) were investigated via timeseries and conjunction analyses. Though the networks engaged in each of the task stages were mostly distinct, regions of ACC, PCC and caudate were consistently activated during each decision-making phase. These results demonstrate (1) that subjective assessments of risk, as well as individual attitudes toward risk, play a significant role in modulating activity within brain regions recruited during decision-making, and (2) that ACC, PCC and caudate are relevant during each phase of a decision-making task requiring subjective valuations, strengthening the role of these regions in self-referential subjective valuations during choice. PMID:19576868
Solubility and bioavailability of stabilized amorphous calcium carbonate.
Meiron, Oren E; Bar-David, Elad; Aflalo, Eliahu D; Shechter, Assaf; Stepensky, David; Berman, Amir; Sagi, Amir
2011-02-01
Since its role in the prevention of osteoporosis in humans was proven some 30 years ago, calcium bioavailability has been the subject of numerous scientific studies. Recent technology allowing the production of a stable amorphous calcium carbonate (ACC) now enables a bioavailability analysis of this unique form of calcium. This study thus compares the solubility and fractional absorption of ACC, ACC with chitosan (ACC-C), and crystalline calcium carbonate (CCC). Solubility was evaluated by dissolving these preparations in dilute phosphoric acid. The results demonstrated that both ACC and ACC-C are more soluble than CCC. Fractional absorption was evaluated by intrinsically labeling calcium carbonate preparations with (45)Ca, orally administrated to rats using gelatin capsules. Fractional absorption was determined by evaluating the percentage of the administrated radioactive dose per milliliter that was measured in the serum, calcium absorption in the femur, and whole-body retention over a 34-hour period. Calcium serum analysis revealed that calcium absorption from ACC and ACC-C preparations was up to 40% higher than from CCC, whereas retention of ACC and ACC-C was up to 26.5% higher than CCC. Absorbed calcium in the femurs of ACC-administrated rats was 30% higher than in CCC-treated animals, whereas 15% more calcium was absorbed following ACC-C treatment than following CCC treatment. This study demonstrates the enhanced solubility and bioavailability of ACC over CCC. The use of stable ACC as a highly bioavailable dietary source for calcium is proposed based on the findings of this study. Copyright © 2011 American Society for Bone and Mineral Research.
Molecular cloning and expression of heteromeric ACCase subunit genes from Jatropha curcas.
Gu, Keyu; Chiam, Huihui; Tian, Dongsheng; Yin, Zhongchao
2011-04-01
Acetyl-CoA carboxylase (ACCase) catalyzes the biotin-dependent carboxylation of acetyl-CoA to produce malonyl-CoA, which is the essential first step in the biosynthesis of long-chain fatty acids. ACCase exists as a multi-subunit enzyme in most prokaryotes and the chloroplasts of most plants and algae, while it is present as a multi-domain enzyme in the endoplasmic reticulum of most eukaryotes. The heteromeric ACCase of higher plants consists of four subunits: an α-subunit of carboxyltransferase (α-CT, encoded by accA gene), a biotin carboxyl carrier protein (BCCP, encoded by accB gene), a biotin carboxylase (BC, encoded by accC gene) and a β-subunit of carboxyltransferase (β-CT, encoded by accD gene). In this study, we cloned and characterized the genes accA, accB1, accC and accD that encode the subunits of heteromeric ACCase in Jatropha (Jatropha curcas), a potential biofuel plant. The full-length cDNAs of the four subunit genes were isolated from a Jatropha cDNA library and by using 5' RACE, whereas the genomic clones were obtained from a Jatropha BAC library. They encode a 771 amino acid (aa) α-CT, a 286-aa BCCP1, a 537-aa BC and a 494-aa β-CT, respectively. The single-copy accA, accB1 and accC genes are nuclear genes, while the accD gene is located in chloroplast genome. Jatropha α-CT, BCCP1, BC and β-CT show high identity to their homologues in other higher plants at amino acid level and contain all conserved domains for ACCase activity. The accA, accB1, accC and accD genes are temporally and spatially expressed in the leaves and endosperm of Jatropha plants, which are regulated by plant development and environmental factors. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Genotype-specific enrichment of ACC deaminase-positive bacteria in winter wheat rhizospheres
USDA-ARS?s Scientific Manuscript database
Bacteria that produce ACC deaminase promote plant growth and development by lowering levels of the stress hormone ethylene through deamination of 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor of ethylene. Therefore, it is hypothesized that ACC deaminase positive (ACC+) bacteri...
Innovative state and local planning for coordinated transportation.
DOT National Transportation Integrated Search
2002-02-01
The study examines seven specific planning strategies that can be used as part of a flexible regional planning process for coordinating transportation services of health and human service and transit agencies. The DOT/DHHS Coordinating Council on Acc...
DOT National Transportation Integrated Search
2000-05-01
The current safety and loss control program for the South Dakota Department of Transportation is not reaching its full potential and does not adequately prevent accidents and injuries. The Department has experienced an unacceptably high number of acc...
NASA Astrophysics Data System (ADS)
Trahanovsky, K.; Whitledge, T. E.
2016-02-01
We examined nutrient and chlorophyll-a (chl) concentrations from bottle samples collected from 0-50 m depth in the Northern Gulf of Alaska along the Seward Line transect on 56 cruises from 1998-2010. We computed monthly average concentrations of macronutrients (N, P, and Si) and chlorophyll-a by depth at four major stations along the transect to describe the regular seasonal progression of the nutricline and typical water column distributions of chlorophyll-a in this seasonally productive, downwelling coastal zone. The across-shelf transect displayed two different patterns of seasonal progression clearly associated with the Alaska Coastal Current (ACC) and Alaskan Stream (AS) current systems. The annual cycle of nutrient drawdown and replenishment is remarkably consistent from year to year within each system and is well correlated with chl measurements. The spring bloom begins earlier and nutrient depletion is sustained longer in the near-shore ACC then in the AS system centered over the shelf break. Chlorophyll-a concentrations frequently peak at 10-20m depth in both systems during July through October, as nutrients remain depleted in the top 10m. Subsurface nutrients (20 - 50 m depth) begin to recover between July and August and then experience a secondary drawdown between August and October, consistent with higher chl levels observed during the fall bloom. Interannual variability in the progression of the nutricline and the relative contribution of subsurface chl to total chl is presented. Physical data demonstrate increasing stratification in this region due to climate change; the implications for nutrient dynamics and primary production are discussed.
Rabany, Liron; Diefenbach, Gretchen J; Bragdon, Laura B; Pittman, Brian P; Zertuche, Luis; Tolin, David F; Goethe, John W; Assaf, Michal
2017-06-01
Generalized anxiety disorder (GAD) and social anxiety disorder (SAD) are currently considered distinct diagnostic categories. Accumulating data suggest the study of anxiety disorders may benefit from the use of dimensional conceptualizations. One such dimension of shared dysfunction is emotion regulation (ER). The current study evaluated dimensional (ER) and categorical (diagnosis) neurocorrelates of resting-state functional connectivity (rsFC) in participants with GAD and SAD and healthy controls (HC). Functional magnetic resonance imaging (fMRI) rsFC was estimated between all regions of the default mode network (DMN), salience network (SN), and bilateral amygdala (N = 37: HC-19; GAD-10; SAD-8). Thereafter, rsFC was predicted by both ER, (using the Difficulties in Emotion Regulation Scale [DERS]), and diagnosis (DSM-5) within a single unified analysis of covariance (ANCOVA). For the ER dimension, there was a significant association between impaired ER abilities and anticorrelated rsFC of amygdala and DMN (L.amygdala-ACC: p = 0.011, beta = -0.345), as well as amygdala and SN (L.amygdala-posterior cingulate cortex [PCC]: p = 0.032, beta = -0.409). Diagnostic status was significantly associated with rsFC differences between the SAD and HC groups, both within the DMN (PCC-MPFC: p = 0.009) and between the DMN and SN (R.LP-ACC: p = 0.010). Although preliminary, our results exemplify the potential contribution of the dimensional approach to the study of GAD and SAD and support a combined categorical and dimensional model of rsFC of anxiety disorders.
24 CFR 982.151 - Annual contributions contract.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Contract and PHA Administration of Program § 982.151 Annual contributions contract. (a) Nature of ACC. (1) An annual contributions contract (ACC) is a written contract between HUD and a PHA. Under the ACC... owners and for the PHA administrative fee. The ACC specifies the maximum payment over the ACC term. The...
24 CFR 982.151 - Annual contributions contract.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Contract and PHA Administration of Program § 982.151 Annual contributions contract. (a) Nature of ACC. (1) An annual contributions contract (ACC) is a written contract between HUD and a PHA. Under the ACC... owners and for the PHA administrative fee. The ACC specifies the maximum payment over the ACC term. The...
Pleasure in using adaptive cruise control: A questionnaire study in The Netherlands.
de Winter, J C F; Gorter, C M; Schakel, W J; van Arem, B
2017-02-17
Adaptive cruise control (ACC), a technology that allows for automated car following, is becoming increasingly prevalent. Previous surveys have shown that drivers generally regard ACC as pleasant but that they have to intervene when the ACC reaches its operational limits. The former research has been mostly concerned with specific car brands and does not fully reflect the diversity of ACC types in traffic today. The objective of the present research was to establish the determinants of pleasure in using ACC. A 55-item online questionnaire was completed by Dutch users of diverse ACC systems. Respondents (N = 182) rated their ACC highly, with a mean score of 8.0 on a scale from 1 (extraordinarily negative) to 10 (extraordinarily positive) and were most pleased with ACC on high-speed roads and in low-density traffic. Moreover, the findings point to specific operational limits such as associated with cut-in situations. Pleasure was greater for the types of ACC that are able to decelerate to a full stop, according to 48% of our sample. An analysis of the free-response items indicated that respondents who were displeased with ACC mentioned its occasional clumsiness and the dangerous situations it may evoke, whereas those who were pleased with ACC valued the complementarity of human and machine and emphasized the roles of responsibility and experience in using ACC. Pleasure in using ACC is a function of both technological advances and human factors.
Reliability and Validity of 2 Self-Report Measures to Assess Sedentary Behavior in Older Adults.
Gennuso, Keith P; Matthews, Charles E; Colbert, Lisa H
2015-05-01
The purpose of this study was to examine the reliability and validity of 2 currently available physical activity surveys for assessing time spent in sedentary behavior (SB) in older adults. Fifty-eight adults (≥65 years) completed the Yale Physical Activity Survey for Older Adults (YPAS) and Community Health Activities Model Program for Seniors (CHAMPS) before and after a 10-day period during which they wore an ActiGraph accelerometer (ACC). Intraclass correlation coefficients (ICC) examined test-retest reliability. Overall percent agreement and a kappa statistic examined YPAS validity. Lin's concordance correlation, Pearson correlation, and Bland-Altman analysis examined CHAMPS validity. Both surveys had moderate test-retest reliability (ICC: YPAS = 0.59 (P < .001), CHAMPS = 0.64 (P < .001)) and significantly underestimated SB time. Agreement between YPAS and ACC was low (κ = -0.0003); however, there was a linear increase (P < .01) in ACC-derived SB time across YPAS response categories. There was poor agreement between ACC-derived SB and CHAMPS (Lin's r = .005; 95% CI, -0.010 to 0.020), and no linear trend across CHAMPS quartiles (P = .53). Neither of the surveys should be used as the sole measure of SB in a study; though the YPAS has the ability to rank individuals, providing it with some merit for use in correlational SB research.
Kim, Dae-Eun; Shin, Jung-Hyun; Kim, Young-Hoon; Eom, Tae-Hoon; Kim, Sung-Hun; Kim, Jung-Min
2016-01-01
Acute confusional migraine (ACM) shows typical electroencephalography (EEG) patterns of diffuse delta slowing and frontal intermittent rhythmic delta activity (FIRDA). The pathophysiology of ACM is still unclear but these patterns suggest neuronal dysfunction in specific brain areas. We performed source localization analysis of IRDA (in the frequency band of 1-3.5 Hz) to better understand the ACM mechanism. Typical IRDA EEG patterns were recorded in a patient with ACM during the acute stage. A second EEG was obtained after recovery from ACM. To identify source localization of IRDA, statistical non-parametric mapping using standardized low-resolution brain electromagnetic tomography was performed for the delta frequency band comparisons between ACM attack and non-attack periods. A difference in the current density maximum was found in the dorsal anterior cingulated cortex (ACC). The significant differences were widely distributed over the frontal, parietal, temporal and limbic lobe, paracentral lobule and insula and were predominant in the left hemisphere. Dorsal ACC dysfunction was demonstrated for the first time in a patient with ACM in this source localization analysis of IRDA. The ACC plays an important role in the frontal attentional control system and acute confusion. This dysfunction of the dorsal ACC might represent an important ACM pathophysiology.
Grundy, John G; Shedden, Judith M
2014-05-01
In the present study, we examine electrophysiological correlates of factors influencing an adjustment in cognitive control known as the bivalency effect. During task-switching, the occasional presence of bivalent stimuli in a block of univalent trials is enough to elicit a response slowing on all subsequent univalent trials. Bivalent stimuli can be congruent or incongruent with respect to the response afforded by the irrelevant stimulus feature. Here we show that the incongruent bivalency effect, the congruent bivalency effect, and an effect of a simple violation of expectancy are captured at a frontal ERP component (between 300 and 550ms) associated with ACC activity, and that the unexpectedness effect is distinguished from both congruent and incongruent bivalency effects at an earlier component (100-120ms) associated with the temporal parietal junction. We suggest that the frontal component reflects the dACC's role in predicting future cognitive load based on recent history. In contrast, the posterior component may index early visual feature extraction in response to bivalent stimuli that cue currently ongoing tasks; dACC activity may trigger the temporal parietal activity only when specific task cueing is involved and not for simple violations of expectancy. Copyright © 2014 Elsevier Ltd. All rights reserved.
Kim, Shin Hye; Jang, Ji Hye; Lee, Sang-Yeon; Han, Jae Joon; Koo, Ja-Won; Vanneste, Sven; De Ridder, Dirk; Song, Jae-Jin
2016-01-01
Although tinnitus retraining therapy (TRT) is efficacious in most patients, the exact mechanism is unclear and no predictor of improvement is available. We correlated the extent of improvement with pre-TRT quantitative electroencephalography (qEEG) findings to identify neural predictors of improvement after TRT. Thirty-two patients with debilitating tinnitus were prospectively enrolled, and qEEG data were recorded before their initial TRT sessions. Three months later, these qEEG findings were correlated with the percentage improvements in the Tinnitus Handicap Inventory (THI) scores, and numeric rating scale (NRS) scores of tinnitus loudness and tinnitus perception. The THI score improvement was positively correlated with the pre-treatment activities of the left insula and the left rostral and pregenual anterior cingulate cortices (rACC/pgACC), which control parasympathetic activity. Additionally, the activities of the right auditory cortices and the parahippocampus, areas that generate tinnitus, negatively correlated with improvements in loudness. Improvements in the NRS scores of tinnitus perception correlated positively with the pre-TRT activities of the bilateral rACC/pgACC, areas suggested to form the core of the noise-canceling system. The current study supports both the classical neurophysiological and integrative models of tinnitus; our results serve as a milestone in the development of precision medicine in the context of TRT. PMID:27381994
Kim, Shin Hye; Jang, Ji Hye; Lee, Sang-Yeon; Han, Jae Joon; Koo, Ja-Won; Vanneste, Sven; De Ridder, Dirk; Song, Jae-Jin
2016-07-06
Although tinnitus retraining therapy (TRT) is efficacious in most patients, the exact mechanism is unclear and no predictor of improvement is available. We correlated the extent of improvement with pre-TRT quantitative electroencephalography (qEEG) findings to identify neural predictors of improvement after TRT. Thirty-two patients with debilitating tinnitus were prospectively enrolled, and qEEG data were recorded before their initial TRT sessions. Three months later, these qEEG findings were correlated with the percentage improvements in the Tinnitus Handicap Inventory (THI) scores, and numeric rating scale (NRS) scores of tinnitus loudness and tinnitus perception. The THI score improvement was positively correlated with the pre-treatment activities of the left insula and the left rostral and pregenual anterior cingulate cortices (rACC/pgACC), which control parasympathetic activity. Additionally, the activities of the right auditory cortices and the parahippocampus, areas that generate tinnitus, negatively correlated with improvements in loudness. Improvements in the NRS scores of tinnitus perception correlated positively with the pre-TRT activities of the bilateral rACC/pgACC, areas suggested to form the core of the noise-canceling system. The current study supports both the classical neurophysiological and integrative models of tinnitus; our results serve as a milestone in the development of precision medicine in the context of TRT.
Solomon, Marjorie; Ragland, J Daniel; Niendam, Tara A; Lesh, Tyler A; Beck, Jonathan S; Matter, John C; Frank, Michael J; Carter, Cameron S
2015-11-01
To investigate the neural mechanisms underlying impairments in generalizing learning shown by adolescents with autism spectrum disorder (ASD). A total of 21 high-functioning individuals with ASD aged 12 to 18 years, and 23 gender-, IQ-, and age-matched adolescents with typical development (TYP), completed a transitive inference (TI) task implemented using rapid event-related functional magnetic resonance imaging (fMRI). Participants were trained on overlapping pairs in a stimulus hierarchy of colored ovals where A>B>C>D>E>F and then tested on generalizing this training to new stimulus pairings (AF, BD, BE) in a "Big Game." Whole-brain univariate, region of interest, and functional connectivity analyses were used. During training, the TYP group exhibited increased recruitment of the prefrontal cortex (PFC), whereas the group with ASD showed greater functional connectivity between the PFC and the anterior cingulate cortex (ACC). Both groups recruited the hippocampus and caudate comparably; however, functional connectivity between these regions was positively associated with TI performance for only the group with ASD. During the Big Game, the TYP group showed greater recruitment of the PFC, parietal cortex, and the ACC. Recruitment of these regions increased with age in the group with ASD. During TI, TYP individuals recruited cognitive control-related brain regions implicated in mature problem solving/reasoning including the PFC, parietal cortex, and ACC, whereas the group with ASD showed functional connectivity of the hippocampus and the caudate that was associated with task performance. Failure to reliably engage cognitive control-related brain regions may produce less integrated flexible learning in individuals with ASD unless they are provided with task support that, in essence, provides them with cognitive control; however, this pattern may normalize with age. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Anterior cingulate cortex and intuitive bias detection during number conservation.
Simon, Grégory; Lubin, Amélie; Houdé, Olivier; De Neys, Wim
2015-01-01
Children's number conservation is often biased by misleading intuitions but the precise nature of these conservation errors is not clear. A key question is whether children detect that their erroneous conservation judgment is unwarranted. The present study reanalyzed available fMRI data to test the implication of the anterior cingulate cortex (ACC) in this detection process. We extracted mean BOLD (Blood Oxygen Level Dependent) signal values in an independently defined ACC region of interest (ROI) during presentation of classic and control number conservation problems. In classic trials, an intuitively cued visuospatial response conflicted with the correct conservation response, whereas this conflict was not present in the control trials. Results showed that ACC activation increased when solving the classic conservation problems. Critically, this increase did not differ between participants who solved the classic problems correctly (i.e., so-called conservers) and incorrectly (i.e., so-called non-conservers). Additional control analyses of inferior and lateral prefrontal ROIs showed that the group of conservers did show stronger activation in the right inferior frontal gyrus and right lateral middle frontal gyrus. In line with recent behavioral findings, these data lend credence to the hypothesis that even non-conserving children detect the biased nature of their judgment. The key difference between conservers and non-conservers seems to lie in a differential recruitment of inferior and lateral prefrontal regions associated with inhibitory control.
Interpersonal violence in posttraumatic women: brain networks triggered by trauma-related pictures.
Neumeister, Paula; Feldker, Katharina; Heitmann, Carina Y; Helmich, Ruth; Gathmann, Bettina; Becker, Michael P I; Straube, Thomas
2017-04-01
Interpersonal violence (IPV) is one of the most frequent causes for the development of posttraumatic stress disorder (PTSD) in women. Trauma-related triggers have been proposed to evoke automatic emotional responses in PTSD. The present functional magnetic resonance study investigated the neural basis of trauma-related picture processing in women with IPV-PTSD (n = 18) relative to healthy controls (n = 18) using a newly standardized trauma-related picture set and a non-emotional vigilance task. We aimed to identify brain activation and connectivity evoked by trauma-related pictures, and associations with PTSD symptom severity. We found hyperactivation during trauma-related vs neutral picture processing in both subcortical [basolateral amygdala (BLA), thalamus, brainstem] and cortical [anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), insula, occipital cortex] regions in IPV-PTSD. In patients, brain activation in amygdala, ACC, insula, occipital cortex and brainstem correlated positively with symptom severity. Furthermore, connectivity analyses revealed hyperconnectivity between BLA and dorsal ACC/mPFC. Results show symptom severity-dependent brain activation and hyperconnectivity in response to trauma-related pictures in brain regions related to fear and visual processing in women suffering from IPV-PTSD. These brain mechanisms appear to be associated with immediate responses to trauma-related triggers presented in a non-emotional context in this PTSD subgroup. © The Author (2016). Published by Oxford University Press.
Merino-Ramos, Teresa; Vázquez-Calvo, Ángela; Casas, Josefina; Sobrino, Francisco; Saiz, Juan-Carlos
2015-01-01
West Nile virus (WNV) is a neurotropic flavivirus transmitted by the bite of mosquitoes that causes meningitis and encephalitis in humans, horses, and birds. Several studies have highlighted that flavivirus infection is highly dependent on cellular lipids for virus replication and infectious particle biogenesis. The first steps of lipid synthesis involve the carboxylation of acetyl coenzyme A (acetyl-CoA) to malonyl-CoA that is catalyzed by the acetyl-CoA carboxylase (ACC). This makes ACC a key enzyme of lipid synthesis that is currently being evaluated as a therapeutic target for different disorders, including cancers, obesity, diabetes, and viral infections. We have analyzed the effect of the ACC inhibitor 5-(tetradecyloxy)-2-furoic acid (TOFA) on infection by WNV. Lipidomic analysis of TOFA-treated cells confirmed that this drug reduced the cellular content of multiple lipids, including those directly implicated in the flavivirus life cycle (glycerophospholipids, sphingolipids, and cholesterol). Treatment with TOFA significantly inhibited the multiplication of WNV in a dose-dependent manner. Further analysis of the antiviral effect of this drug showed that the inhibitory effect was related to a reduction of viral replication. Furthermore, treatment with another ACC inhibitor, 3,3,14,14-tetramethylhexadecanedioic acid (MEDICA 16), also inhibited WNV infection. Interestingly, TOFA and MEDICA 16 also reduced the multiplication of Usutu virus (USUV), a WNV-related flavivirus. These results point to the ACC as a druggable cellular target suitable for antiviral development against WNV and other flaviviruses. PMID:26503654
Merino-Ramos, Teresa; Vázquez-Calvo, Ángela; Casas, Josefina; Sobrino, Francisco; Saiz, Juan-Carlos; Martín-Acebes, Miguel A
2016-01-01
West Nile virus (WNV) is a neurotropic flavivirus transmitted by the bite of mosquitoes that causes meningitis and encephalitis in humans, horses, and birds. Several studies have highlighted that flavivirus infection is highly dependent on cellular lipids for virus replication and infectious particle biogenesis. The first steps of lipid synthesis involve the carboxylation of acetyl coenzyme A (acetyl-CoA) to malonyl-CoA that is catalyzed by the acetyl-CoA carboxylase (ACC). This makes ACC a key enzyme of lipid synthesis that is currently being evaluated as a therapeutic target for different disorders, including cancers, obesity, diabetes, and viral infections. We have analyzed the effect of the ACC inhibitor 5-(tetradecyloxy)-2-furoic acid (TOFA) on infection by WNV. Lipidomic analysis of TOFA-treated cells confirmed that this drug reduced the cellular content of multiple lipids, including those directly implicated in the flavivirus life cycle (glycerophospholipids, sphingolipids, and cholesterol). Treatment with TOFA significantly inhibited the multiplication of WNV in a dose-dependent manner. Further analysis of the antiviral effect of this drug showed that the inhibitory effect was related to a reduction of viral replication. Furthermore, treatment with another ACC inhibitor, 3,3,14,14-tetramethylhexadecanedioic acid (MEDICA 16), also inhibited WNV infection. Interestingly, TOFA and MEDICA 16 also reduced the multiplication of Usutu virus (USUV), a WNV-related flavivirus. These results point to the ACC as a druggable cellular target suitable for antiviral development against WNV and other flaviviruses. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Kuwabara, Masaru; Mansouri, Farshad A.; Buckley, Mark J.
2014-01-01
Monkeys were trained to select one of three targets by matching in color or matching in shape to a sample. Because the matching rule frequently changed and there were no cues for the currently relevant rule, monkeys had to maintain the relevant rule in working memory to select the correct target. We found that monkeys' error commission was not limited to the period after the rule change and occasionally occurred even after several consecutive correct trials, indicating that the task was cognitively demanding. In trials immediately after such error trials, monkeys' speed of selecting targets was slower. Additionally, in trials following consecutive correct trials, the monkeys' target selections for erroneous responses were slower than those for correct responses. We further found evidence for the involvement of the cortex in the anterior cingulate sulcus (ACCs) in these error-related behavioral modulations. First, ACCs cell activity differed between after-error and after-correct trials. In another group of ACCs cells, the activity differed depending on whether the monkeys were making a correct or erroneous decision in target selection. Second, bilateral ACCs lesions significantly abolished the response slowing both in after-error trials and in error trials. The error likelihood in after-error trials could be inferred by the error feedback in the previous trial, whereas the likelihood of erroneous responses after consecutive correct trials could be monitored only internally. These results suggest that ACCs represent both context-dependent and internally detected error likelihoods and promote modes of response selections in situations that involve these two types of error likelihood. PMID:24872558
Saulskaya, Natalia B; Fofonova, Nellia V; Sudorghina, Polina V; Saveliev, Sergey A
2008-08-01
Nucleus accumbens (N.Acc) contains a subclass of nitric oxide (NO)-generating interneurons that are presumably regulated by the dopamine input. Receptor mechanisms underlying dopamine-NO interaction in the N.Acc are poorly understood. In the current study, we used in vivo microdialysis combined with high-performance liquid chromatography to examine participation of dopamine D1 receptors in regulation of extracellular levels of citrulline (an NO co-product) in the medial N.Acc of Sprague-Dawley rats during both pharmacological challenge and a conditioned fear response. The intraaccumbal infusion of the D1 receptor agonist SKF-38393 (100-500 microM) increased dose-dependently the local dialysate citrulline levels. The SKF-38393-induced increase in extracellular citrulline was prevented by intraaccumbal infusions of 500 microM 7-nitroindazole, a neuronal NO synthase inhibitor. In behavioral microdialysis experiment, the accumbal levels of extracellular citrulline markedly increased in rats given a mild footshock paired with tone. The presentation of the tone previously paired with footshock (the conditioned fear response) produced a "conditioned" rise of extracellular citrulline levels in the N.Acc which was attenuated by intraaccumbal infusion of 100 microM SCH-23390, a dopamine D1 receptor antagonist, and prevented by intraaccumbal infusion of 500 microM 7-nitroindazole. The results suggest that in the N.Acc, the dopamine D1 receptors might regulate the neuronal NO synthase activity; this dopamine-dependent mechanism seems to participate in activation of the neuronal NO synthase and probably NO formation in this brain area during the conditioned fear response.
Migliorini, Robyn; Moore, Eileen M.; Glass, Leila; Infante, M. Alejandra; Tapert, Susan F.; Jones, Kenneth Lyons; Mattson, Sarah N.; Riley, Edward P.
2015-01-01
Prenatal alcohol exposure is associated with behavioral disinhibition, yet the brain structure correlates of this deficit have not been determined with sufficient detail. We examined the hypothesis that the structure of the anterior cingulate cortex (ACC) relates to inhibition performance in youth with histories of heavy prenatal alcohol exposure (AE, n = 32) and non-exposed controls (CON, n = 21). Adolescents (12–17 years) underwent structural magnetic resonance imaging yielding measures of gray matter volume, surface area, and thickness across four ACC subregions. A subset of subjects were administered the NEPSY-II Inhibition subtest. MANCOVA was utilized to test for group differences in ACC and inhibition performance and multiple linear regression was used to probe ACC-inhibition relationships. ACC surface area was significantly smaller in AE, though this effect was primarily driven by reduced right caudal ACC (rcACC). AE also performed significantly worse on inhibition speed but not on inhibition accuracy. Regression analyses with the rcACC revealed a significant group × ACC interaction. A smaller rcACC surface area was associated with slower inhibition completion time for AE but was not significantly associated with inhibition in CON. After accounting for processing speed, smaller rcACC surface area was associated with worse (i.e., slower) inhibition regardless of group. Examining processing speed independently, a decrease in rcACC surface area was associated with faster processing speed for CON but not significantly associated with processing speed in AE. Results support the theory that caudal ACC may monitor reaction time in addition to inhibition and highlight the possibility of delayed ACC neurodevelopment in prenatal alcohol exposure. PMID:26025509
Migliorini, Robyn; Moore, Eileen M; Glass, Leila; Infante, M Alejandra; Tapert, Susan F; Jones, Kenneth Lyons; Mattson, Sarah N; Riley, Edward P
2015-10-01
Prenatal alcohol exposure is associated with behavioral disinhibition, yet the brain structure correlates of this deficit have not been determined with sufficient detail. We examined the hypothesis that the structure of the anterior cingulate cortex (ACC) relates to inhibition performance in youth with histories of heavy prenatal alcohol exposure (AE, n = 32) and non-exposed controls (CON, n = 21). Adolescents (12-17 years) underwent structural magnetic resonance imaging yielding measures of gray matter volume, surface area, and thickness across four ACC subregions. A subset of subjects were administered the NEPSY-II Inhibition subtest. MANCOVA was utilized to test for group differences in ACC and inhibition performance and multiple linear regression was used to probe ACC-inhibition relationships. ACC surface area was significantly smaller in AE, though this effect was primarily driven by reduced right caudal ACC (rcACC). AE also performed significantly worse on inhibition speed but not on inhibition accuracy. Regression analyses with the rcACC revealed a significant group × ACC interaction. A smaller rcACC surface area was associated with slower inhibition completion time for AE but was not significantly associated with inhibition in CON. After accounting for processing speed, smaller rcACC surface area was associated with worse (i.e., slower) inhibition regardless of group. Examining processing speed independently, a decrease in rcACC surface area was associated with faster processing speed for CON but not significantly associated with processing speed in AE. Results support the theory that caudal ACC may monitor reaction time in addition to inhibition and highlight the possibility of delayed ACC neurodevelopment in prenatal alcohol exposure. Copyright © 2015 Elsevier B.V. All rights reserved.
Ghattas, Wadih; Giorgi, Michel; Mekmouche, Yasmina; Tanaka, Tsunehiro; Rockenbauer, Antal; Réglier, Marius; Hitomi, Yutaka; Simaan, A Jalila
2008-06-02
Several Cu(II) complexes with ACC (=1-aminocyclopropane carboxylic acid) or AIB (=aminoisobutyric acid) were prepared using 2,2'-bipyridine, 1,10-phenanthroline, and 2-picolylamine ligands: [Cu(2,2'-bipyridine)(ACC)(H2O)](ClO4) (1a), [Cu(1,10-phenanthroline)(ACC)](ClO4) (2a), [Cu(2-picolylamine)(ACC)](ClO4) (3a), and [Cu(2,2'-bipyridine)(AIB)(H2O)](ClO4) (1b). All of the complexes were characterized by X-ray diffraction analysis. The Cu(II)-ACC complexes are able to convert the bound ACC moiety into ethylene in the presence of hydrogen peroxide, in an "ACC-oxidase-like" activity. A few equivalents of base are necessary to deprotonate H2O2 for optimum activity. The presence of dioxygen lowers the yield of ACC conversion into ethylene by the copper(II) complexes. During the course of the reaction of Cu(II)-ACC complexes with H2O2, brown species (EPR silent and lambda max approximately 435 nm) were detected and characterized as being the Cu(I)-ACC complexes that are obtained upon reduction of the corresponding Cu(II) complexes by the deprotonated form of hydrogen peroxide. The geometry of the Cu(I) species was optimized by DFT calculations that reveal a change from square-planar to tetrahedral geometry upon reduction of the copper ion, in accordance with the observed nonreversibility of the redox process. In situ prepared Cu(I)-ACC complexes were also reacted with hydrogen peroxide, and a high level of ethylene formation was obtained. We propose Cu(I)-OOH as a possible active species for the conversion of ACC into ethylene, the structure of which was examined by DFT calculation.
Gao, Jun; Wu, Xiaoyin; Owyang, Chung; Li, Ying
2006-01-01
The anterior cingulate cortex (ACC) is critically involved in processing the affective component of pain sensation. Visceral hypersensitivity is a characteristic of irritable bowel syndrome. Electrophysiological activity of the ACC with regard to visceral sensitization has not been characterized. Single ACC neuronal activities in response to colorectal distension (CRD) were recorded in control, sham-treated rats and viscerally hypersensitive (EA) rats (induced by chicken egg albumin injection, i.p). The ACC neurones of controls failed to respond to 10 or 30 mmHg CRD; only 22% were activated by 50 mmHg CRD. Among the latter, 16.4% exhibited an excitatory response to CRD and were labelled ‘CRD-excited’ neurones. In contrast, CRD (10, 30 and 50 mmHg) markedly increased ACC neuronal responses of EA rats (10%, 28% and 47%, respectively). CRD produced greater pressure-dependent increases in ACC spike firing rates in EA rats compared with controls. Splanchnicectomy combined with pelvic nerve section abolished ACC responses to CRD in EA rats. Spontaneous activity in CRD-excited ACC neurones was significantly higher in EA rats than in controls. CRD-excited ACC neurones in control and EA rats (7 of 16 (42%) and 8 of 20 (40%), respectively) were activated by transcutaneous electrical and thermal stimuli. However, ACC neuronal activity evoked by noxious cutaneous stimuli did not change significantly in EA rats. This study identifies CRD-responsive neurones in the ACC and establishes for the first time that persistence of a heightened visceral afferent nociceptive input to the ACC induces ACC sensitization, characterized by increased spontaneous activity of CRD-excited neurones, decreased CRD pressure threshold, and increased response magnitude. Enhanced ACC nociceptive transmission in viscerally hypersensitive rats is restricted to visceral afferent input. PMID:16239277
Phuchareon, Janyaporn; Ohta, Yoshihito; Woo, Jonathan M.; Eisele, David W.; Tetsu, Osamu
2009-01-01
Adenoid cystic carcinoma (ACC) is the second most common malignant neoplasm of the salivary glands. Most patients survive more than 5 years after surgery and postoperative radiation therapy. The 10 year survival rate, however, drops to 40%, due to locoregional recurrences and distant metastases. Improving long-term survival in ACC requires the development of more effective systemic therapies based on a better understanding of the biologic behavior of ACC. Much preclinical research in this field involves the use of cultured cells and, to date, several ACC cell lines have been established. Authentication of these cell lines, however, has not been reported. We performed DNA fingerprint analysis on six ACC cell lines using short tandem repeat (STR) examinations and found that all six cell lines had been contaminated with other cells. ACC2, ACC3, and ACCM were determined to be cervical cancer cells (HeLa cells), whereas the ACCS cell line was composed of T24 urinary bladder cancer cells. ACCNS and CAC2 cells were contaminated with cells derived from non-human mammalian species: the cells labeled ACCNS were mouse cells and the CAC2 cells were rat cells. These observations suggest that future studies using ACC cell lines should include cell line authentication to avoid the use of contaminated or non-human cells. PMID:19557180
Reward salience and risk aversion underlie differential ACC activity in substance dependence
Alexander, William H.; Fukunaga, Rena; Finn, Peter; Brown, Joshua W.
2015-01-01
The medial prefrontal cortex, especially the dorsal anterior cingulate cortex (ACC), has long been implicated in cognitive control and error processing. Although the association between ACC and behavior has been established, it is less clear how ACC contributes to dysfunctional behavior such as substance dependence. Evidence from neuroimaging studies investigating ACC function in substance users is mixed, with some studies showing disengagement of ACC in substance dependent individuals (SDs), while others show increased ACC activity related to substance use. In this study, we investigate ACC function in SDs and healthy individuals performing a change signal task for monetary rewards. Using a priori predictions derived from a recent computational model of ACC, we find that ACC activity differs between SDs and controls in factors related to reward salience and risk aversion between SDs and healthy individuals. Quantitative fits of a computational model to fMRI data reveal significant differences in best fit parameters for reward salience and risk preferences. Specifically, the ACC in SDs shows greater risk aversion, defined as concavity in the utility function, and greater attention to rewards relative to reward omission. Furthermore, across participants risk aversion and reward salience are positively correlated. The results clarify the role that ACC plays in both the reduced sensitivity to omitted rewards and greater reward valuation in SDs. Clinical implications of applying computational modeling in psychiatry are also discussed. PMID:26106528
Reward salience and risk aversion underlie differential ACC activity in substance dependence.
Alexander, William H; Fukunaga, Rena; Finn, Peter; Brown, Joshua W
2015-01-01
The medial prefrontal cortex, especially the dorsal anterior cingulate cortex (ACC), has long been implicated in cognitive control and error processing. Although the association between ACC and behavior has been established, it is less clear how ACC contributes to dysfunctional behavior such as substance dependence. Evidence from neuroimaging studies investigating ACC function in substance users is mixed, with some studies showing disengagement of ACC in substance dependent individuals (SDs), while others show increased ACC activity related to substance use. In this study, we investigate ACC function in SDs and healthy individuals performing a change signal task for monetary rewards. Using a priori predictions derived from a recent computational model of ACC, we find that ACC activity differs between SDs and controls in factors related to reward salience and risk aversion between SDs and healthy individuals. Quantitative fits of a computational model to fMRI data reveal significant differences in best fit parameters for reward salience and risk preferences. Specifically, the ACC in SDs shows greater risk aversion, defined as concavity in the utility function, and greater attention to rewards relative to reward omission. Furthermore, across participants risk aversion and reward salience are positively correlated. The results clarify the role that ACC plays in both the reduced sensitivity to omitted rewards and greater reward valuation in SDs. Clinical implications of applying computational modeling in psychiatry are also discussed.
NASA Astrophysics Data System (ADS)
Alcalá, J. M.; Natta, A.; Manara, C. F.; Spezzi, L.; Stelzer, B.; Frasca, A.; Biazzo, K.; Covino, E.; Randich, S.; Rigliaco, E.; Testi, L.; Comerón, F.; Cupani, G.; D'Elia, V.
2014-01-01
We present VLT/X-shooter observations of a sample of 36 accreting low-mass stellar and substellar objects (YSOs) in the Lupus star-forming region, spanning a range in mass from ~0.03 to ~1.2 M⊙, but mostly with 0.1 M⊙
24 CFR 941.302 - Annual contributions contract; drawdowns and advances.
Code of Federal Regulations, 2010 CFR
2010-04-01
... execute an ACC or ACC amendment covering the entire amount of reserved development funds or the amount of... part. This ACC or ACC amendment must be executed by both the PHA and HUD before funds can be provided... the ACC for pre-development costs for materials and services related to proposal preparation and...
24 CFR 941.302 - Annual contributions contract; drawdowns and advances.
Code of Federal Regulations, 2011 CFR
2011-04-01
... execute an ACC or ACC amendment covering the entire amount of reserved development funds or the amount of... part. This ACC or ACC amendment must be executed by both the PHA and HUD before funds can be provided... the ACC for pre-development costs for materials and services related to proposal preparation and...
Dehydration-induced amorphous phases of calcium carbonate.
Saharay, Moumita; Yazaydin, A Ozgur; Kirkpatrick, R James
2013-03-28
Amorphous calcium carbonate (ACC) is a critical transient phase in the inorganic precipitation of CaCO3 and in biomineralization. The calcium carbonate crystallization pathway is thought to involve dehydration of more hydrated ACC to less hydrated ACC followed by the formation of anhydrous ACC. We present here computational studies of the transition of a hydrated ACC with a H2O/CaCO3 ratio of 1.0 to anhydrous ACC. During dehydration, ACC undergoes reorganization to a more ordered structure with a significant increase in density. The computed density of anhydrous ACC is similar to that of calcite, the stable crystalline phase. Compared to the crystalline CaCO3 phases, calcite, vaterite, and aragonite, the computed local structure of anhydrous ACC is most-similar to those of calcite and vaterite, but the overall structure is not well described by either. The strong hydrogen bond interaction between the carbonate ions and water molecules plays a crucial role in stabilizing the less hydrated ACC compositions compared to the more hydrated ones, leading to a progressively increasing hydration energy with decreasing water content.
Marjanovic, Jasmina; Chalupska, Dominika; Patenode, Caroline; Coster, Adam; Arnold, Evan; Ye, Alice; Anesi, George; Lu, Ying; Okun, Ilya; Tkachenko, Sergey; Haselkorn, Robert; Gornicki, Piotr
2010-01-01
Acetyl-CoA carboxylase (ACC) is a key enzyme of fatty acid metabolism with multiple isozymes often expressed in different eukaryotic cellular compartments. ACC-made malonyl-CoA serves as a precursor for fatty acids; it also regulates fatty acid oxidation and feeding behavior in animals. ACC provides an important target for new drugs to treat human diseases. We have developed an inexpensive nonradioactive high-throughput screening system to identify new ACC inhibitors. The screen uses yeast gene-replacement strains depending for growth on cloned human ACC1 and ACC2. In “proof of concept” experiments, growth of such strains was inhibited by compounds known to target human ACCs. The screen is sensitive and robust. Medium-size chemical libraries yielded new specific inhibitors of human ACC2. The target of the best of these inhibitors was confirmed with in vitro enzymatic assays. This compound is a new drug chemotype inhibiting human ACC2 with 2.8 μM IC50 and having no effect on human ACC1 at 100 μM. PMID:20439761
Magliano, Ana C M; da Silva, Flávia Maia; Teixeira, Marta M G; Alfieri, Silvia C
2009-11-01
Acanthamoeba spp., known to cause keratitis and granulomatous encephalitis in humans, are frequently isolated from a variety of water sources. Here we report for the first time the characterization of an Acanthamoeba sp. (ACC01) isolated from tap water in Brazil. This organism is currently being maintained in an axenic growth medium. Phylogenetic analysis based on SSU rRNA gene sequences positioned the new isolate in genotype T4, closest to the keratitis-causing isolate, A. polyphaga ATCC 30461 ( approximately 99% similarity). Acanthamoeba ACC01 and A. polyphaga 30461 both grew at 37 degrees C and were osmotically resistant, multiplying in hyperosmolar medium. Both isolates secreted comparable amounts of proteolytic enzymes, including serine peptidases that were optimally active at a near neutral/alkaline pH and resolved identically in gelatin gels. Incubation of gels at pH 4.0 with 2mM DTT also indicated the secretion of similar cysteine peptidases. Altogether, the results point to the pathogenic potential of Acanthamoeba ACC01.
Submesoscale Rossby waves on the Antarctic circumpolar current.
Taylor, John R; Bachman, Scott; Stamper, Megan; Hosegood, Phil; Adams, Katherine; Sallee, Jean-Baptiste; Torres, Ricardo
2018-03-01
The eastward-flowing Antarctic circumpolar current (ACC) plays a central role in the global ocean overturning circulation and facilitates the exchange of water between the ocean surface and interior. Submesoscale eddies and fronts with scales between 1 and 10 km are regularly observed in the upper ocean and are associated with strong vertical circulations and enhanced stratification. Despite their importance in other locations, comparatively little is known about submesoscales in the Southern Ocean. We present results from new observations, models, and theories showing that submesoscales are qualitatively changed by the strong jet associated with the ACC in the Scotia Sea, east of Drake Passage. Growing submesoscale disturbances develop along a dense filament and are transformed into submesoscale Rossby waves, which propagate upstream relative to the eastward jet. Unlike their counterparts in slower currents, the submesoscale Rossby waves do not destroy the underlying frontal structure. The development of submesoscale instabilities leads to strong net subduction of water associated with a dense outcropping filament, and later, the submesoscale Rossby waves are associated with intense vertical circulations.
NASA Astrophysics Data System (ADS)
Bentley, A. P.; Petcovic, H. L.; Cassidy, D. P.; Eklund, P. R.
2016-12-01
Anthropogenic climate change (ACC) poses a threat to the safety and well-being of the United States. For science educators, the first step to mitigating this problem is helping the public understand the science of climate change so they make knowledgeable political and personal choices. However, some Americans remain unconvinced that the recent rapid rise of Earth's temperature is caused by human activities. A portion of anti-climate change information comes from groups that stand to lose power and revenue if the public begins to favor greenhouse gas limiting policies. These groups thwart policy initiatives through the production and dissemination of anti-ACC messages to news media, blogs, and among politicians. It is important for educators to understand these dissenter messages in order to avoid inadvertently using them. In earlier work, we developed a Likert-type survey instrument from online videos of authentic dissenter messages. Using this instrument and exploratory factor analysis (N=133), we identified five categories of counter ACC arguments: naïve statements which either use scientific misconceptions to dismiss or attack the science of ACC; sophisticated scientific statements which imply warming is not anthropogenic; arguments that assert recent changes are natural or out of our control; arguments that imply current warming is simply part of a larger cycle; and statements that highlight benefits of a warming climate. For the present study we validated the instrument using multiple methods including confirmatory factor analysis (N=151). Results suggest our instrument may identify how different populations agree with misleading ACC material. Here we explore two questions: (1) does a relationship exist between dissenter message agreement and primary news source? and (2) does a relationship exist between dissenter statement agreement and ACC acceptance? This information could be used to generate tailored resources that could inoculate people from misleading information.
Differences in resting corticolimbic functional connectivity in bipolar I euthymia
Torrisi, Salvatore; Moody, Teena D; Vizueta, Nathalie; Thomason, Moriah E; Monti, Martin M; Townsend, Jennifer D; Bookheimer, Susan Y; Altshuler, Lori L
2012-01-01
Objective We examined resting state functional connectivity in the brain between key emotion regulation regions in bipolar I disorder to delineate differences in coupling from healthy subjects. Methods Euthymic subjects with bipolar I disorder (n = 20) and matched healthy subjects (n = 20) participated in a resting state functional magnetic resonance imaging scan. Low frequency fluctuations in blood oxygen level-dependent (BOLD) signal were correlated in the six connections between four anatomically-defined nodes: left and right amygdala and left and right ventrolateral prefrontal cortex (vlPFC). Seed-to-voxel connectivity results were probed for commonly coupled regions. Following this, an identified region was included in a mediation analysis to determine the potential of mediation. Results The bipolar I disorder group exhibited significant hyperconnectivity between right amygdala and right vlPFC relative to healthy subjects. The connectivity between these regions in the bipolar I disorder group was partially mediated by activity in the anterior cingulate cortex (ACC). Conclusions Greater coupling between right amygdala and right vlPFC and their partial mediation by the ACC were found in bipolar I disorder subjects in remission and in the absence of a psychological task. These findings have implications for a trait-related and clinically-important imaging biomarker. PMID:23347587
Neural mechanisms of dissonance: an fMRI investigation of choice justification.
Kitayama, Shinobu; Chua, Hannah Faye; Tompson, Steven; Han, Shihui
2013-04-01
Cognitive dissonance theory proposes that difficult choice produces negatively arousing cognitive conflict (called dissonance), which motivates the chooser to justify her decision by increasing her preference for the chosen option while decreasing her preference for the rejected option. At present, however, neural mechanisms of dissonance are poorly understood. To address this gap of knowledge, we scanned 24 young Americans as they made 60 choices between pairs of popular music CDs. As predicted, choices between CDs that were close (vs. distant) in attractiveness (referred to as difficult vs. easy choices) resulted in activations of the dorsal anterior cingulate cortex (dACC), a brain region associated with cognitive conflict, and the left anterior insula (left aINS), a region often linked with aversive emotional arousal. Importantly, a separate analysis showed that choice-justifying attitude change was predicted by the in-choice signal intensity of the posterior cingulate cortex (PCC), a region that is linked to self-processing. The three regions identified (dACC, left aINS, and PCC) were correlated, within-subjects, across choices. The results were interpreted to support the hypothesis that cognitive dissonance plays a key role in producing attitudes that justify the choice. Copyright © 2012 Elsevier Inc. All rights reserved.
Yu, Chunshui; Zhou, Yuan; Liu, Yong; Jiang, Tianzi; Dong, Haiwei; Zhang, Yunting; Walter, Martin
2011-02-14
The four-region model with 7 specified subregions represents a theoretical construct of functionally segregated divisions of the cingulate cortex based on integrated neurobiological assessments. Under this framework, we aimed to investigate the functional specialization of the human cingulate cortex by analyzing the resting-state functional connectivity (FC) of each subregion from a network perspective. In 20 healthy subjects we systematically investigated the FC patterns of the bilateral subgenual (sACC) and pregenual (pACC) anterior cingulate cortices, anterior (aMCC) and posterior (pMCC) midcingulate cortices, dorsal (dPCC) and ventral (vPCC) posterior cingulate cortices and retrosplenial cortices (RSC). We found that each cingulate subregion was specifically integrated in the predescribed functional networks and showed anti-correlated resting-state fluctuations. The sACC and pACC were involved in an affective network and anti-correlated with the sensorimotor and cognitive networks, while the pACC also correlated with the default-mode network and anti-correlated with the visual network. In the midcingulate cortex, however, the aMCC was correlated with the cognitive and sensorimotor networks and anti-correlated with the visual, affective and default-mode networks, whereas the pMCC only correlated with the sensorimotor network and anti-correlated with the cognitive and visual networks. The dPCC and vPCC involved in the default-mode network and anti-correlated with the sensorimotor, cognitive and visual networks, in contrast, the RSC was mainly correlated with the PCC and thalamus. Based on a strong hypothesis driven approach of anatomical partitions of the cingulate cortex, we could confirm their segregation in terms of functional neuroanatomy, as suggested earlier by task studies or exploratory multi-seed investigations. Copyright © 2010 Elsevier Inc. All rights reserved.
Shi, Xian-Feng; Forrest, Lauren N.; Kuykendall, M. Danielle; Prescot, Andrew P.; Sung, Young-Hoon; Huber, Rebekah S.; Hellem, Tracy L.; Jeong, Eun-Kee; Renshaw, Perry F.; Kondo, Douglas G.
2015-01-01
Background Delayed diagnosis in bipolar disorder (BD) due to misdiagnosis as major depressive disorder (MDD) is a significant public health concern. Thus, identification of relevant diagnostic biomarkers is a critical unmet need, particularly early in the course of illness. The anterior cingulate cortex (ACC) is thought to play an important role in mood disorder pathophysiology. Case-control studies utilizing proton-1 magnetic resonance spectroscopy (1H-MRS) have found increased total choline levels in several brain regions in MDD. However, there are no published 1H-MRS reports directly comparing adolescents with MDD and BD. We hypothesized that ACC choline levels would be increased in adolescents with unipolar versus bipolar depression. Methods We studied depressed adolescents with MDD (n=28; mean age 17.0±2.1 years) and BD (n=9; 17.3±3.1 years). A Siemens Verio 3-Tesla clinical MRI system was used to acquire scans, using a single-voxel PRESS sequence. The voxel (18.75 cm3) was positioned on the ACC in the midsagittal plane. To remove potential gender effects, only female adolescent participants were included. Data were analyzed using the ANOVA and post-hoc Tukey tests. Results A significantly increased ACC choline/creatine ratio was observed in participants with MDD (mean=0.253±0.021) compared to BD (mean=0.219±0.020) (p=0.0002). There were no significant differences in the other 1H-MRS metabolites. Limitations Cross sectional design, single gender sample, limited sample size. Conclusions The present findings suggest that ACC total choline may have the potential to serve as a diagnostic biomarker in adolescent mood disorders. PMID:25082110
Bogdanova, Vera S.; Zaytseva, Olga O.; Mglinets, Anatoliy V.; Shatskaya, Natalia V.; Kosterin, Oleg E.; Vasiliev, Gennadiy V.
2015-01-01
In crosses of wild and cultivated peas (Pisum sativum L.), nuclear-cytoplasmic incompatibility frequently occurs manifested as decreased pollen fertility, male gametophyte lethality, sporophyte lethality. High-throughput sequencing of plastid genomes of one cultivated and four wild pea accessions differing in cross-compatibility was performed. Candidate genes for involvement in the nuclear-plastid conflict were searched in the reconstructed plastid genomes. In the annotated Medicago truncatula genome, nuclear candidate genes were searched in the portion syntenic to the pea chromosome region known to harbor a locus involved in the conflict. In the plastid genomes, a substantial variability of the accD locus represented by nucleotide substitutions and indels was found to correspond to the pattern of cross-compatibility among the accessions analyzed. Amino acid substitutions in the polypeptides encoded by the alleles of a nuclear locus, designated as Bccp3, with a complementary function to accD, fitted the compatibility pattern. The accD locus in the plastid genome encoding beta subunit of the carboxyltransferase of acetyl-coA carboxylase and the nuclear locus Bccp3 encoding biotin carboxyl carrier protein of the same multi-subunit enzyme were nominated as candidate genes for main contribution to nuclear-cytoplasmic incompatibility in peas. Existence of another nuclear locus involved in the accD-mediated conflict is hypothesized. PMID:25789472
Social anxiety disorder exhibit impaired networks involved in self and theory of mind processing.
Cui, Qian; Vanman, Eric J; Long, Zhiliang; Pang, Yajing; Chen, Yuyan; Wang, Yifeng; Duan, Xujun; Chen, Heng; Gong, Qiyong; Zhang, Wei; Chen, Huafu
2017-08-01
Most previous studies regarding social anxiety disorder (SAD) have focused on the role of emotional dysfunction, while impairments in self- and theory of mind (ToM)-processing have relatively been neglected. This study utilised functional connectivity density (FCD), resting-state functional connectivity (RSFC) and discriminant analyses to investigate impairments in self- and ToM-related networks in patients with SAD. Patients with SAD exhibited decreased long-range FCD in the right rostral anterior cingulate cortex (rACC) and decreased short-range FCD in the right superior temporal gyrus (STG)-key nodes involved in self- and ToM-processing, respectively. Decreased RSFC of the right rACC and STG with widespread frontal, temporal, posteromedial, sensorimotor, and somatosensory, regions was also observed in patients with SAD. Altered RSFC between the right rACC and bilateral superior frontal gyrus, between the right rACC and right middle frontal gyrus, and within the right STG itself provided the greatest contribution to individual diagnoses of SAD, with an accuracy of 84.5%. These results suggest that a lack of cognitive inhibition on emotional self-referential processing as well as impairments in social information integration may play critical roles in the pathomechanism of SAD and highlight the importance of recognising such features in the diagnosis and treatment of SAD. © The Author (2017). Published by Oxford University Press.
A hydrologic drying bias in water-resource impact analyses of anthropogenic climate change
Milly, Paul; Dunne, Krista A.
2017-01-01
For water-resource planning, sensitivity of freshwater availability to anthropogenic climate change (ACC) often is analyzed with “offline” hydrologic models that use precipitation and potential evapotranspiration (Ep) as inputs. Because Ep is not a climate-model output, an intermediary model of Ep must be introduced to connect the climate model to the hydrologic model. Several Ep methods are used. The suitability of each can be assessed by noting a credible Ep method for offline analyses should be able to reproduce climate models’ ACC-driven changes in actual evapotranspiration in regions and seasons of negligible water stress (Ew). We quantified this ability for seven commonly used Ep methods and for a simple proportionality with available energy (“energy-only” method). With the exception of the energy-only method, all methods tend to overestimate substantially the increase in Ep associated with ACC. In an offline hydrologic model, the Ep-change biases produce excessive increases in actual evapotranspiration (E), whether the system experiences water stress or not, and thence strong negative biases in runoff change, as compared to hydrologic fluxes in the driving climate models. The runoff biases are comparable in magnitude to the ACC-induced runoff changes themselves. These results suggest future hydrologic drying (wetting) trends likely are being systematically and substantially overestimated (underestimated) in many water-resource impact analyses.
NASA Astrophysics Data System (ADS)
Brearley, J. A.; Sheen, K. L.; Naveira-Garabato, A. C.
2012-04-01
A key component of DIMES (Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean) is the deployment of a two-year cross-shaped mooring array in the Antarctic Circumpolar Current to the east of Drake Passage close to 57°W. Motivation for the cluster arises from the need to understand how eddies dissipate in the Southern Ocean, and specifically how much energy is extracted from the mesoscale by breaking internal waves, which in turn leads to turbulent mixing. The location of the mooring cluster was chosen to fulfil these objectives, being situated in a region of pronounced finestructure with high eddy kinetic energy and rough topography. The array, comprising 34 current meters and Microcats and a downward-looking ADCP, was first deployed in December 2009 and serviced in December 2010. Time series of current meter results from the most heavily-instrumented 'C' mooring indicate that a strong (up to 80 cms-1) surface-intensified north-eastward directed ACC occupies the region for most of the year, with over 85% of the variability in current speed being accounted for by equivalent barotropic fluctuations. A strong mean poleward heat flux is observed at the site, which compares favourably in magnitude with literature results from other ACC locations. Interestingly, four episodes of mid-depth (~2000 m) current speed maxima, each of a few days duration, were found during the 360-day time series, a situation also observed by the lowered ADCP during mooring servicing in December 2010. Early results indicate that these episodes, which coincide with time minima in stratification close to 2000 m, could profoundly influence the nature of eddy-internal wave interactions at these times. Quantification of the energy budget at the mooring cluster has been a key priority. When compared with previous moorings located in Drake Passage (Bryden, 1977), a near threefold-increase in mean eddy kinetic energy (EKE) is observed despite a small reduction in the mean kinetic energy between these sites. The magnitude of interactions between the available potential energy and EKE and between the EKE and mean kinetic energy are of similar magnitude to those observed in Drake Passage. Unfortunately, the collapse of two moorings early in 2010 has meant that second-year data will be required before the exchange of energy between the eddy and internal wave frequency bands can be rigorously quantified. However, data from the downward-looking ADCP between 2700 and 3400 m is starting to identify the important frequencies and mechanisms of internal wave activity.
2008-09-01
under- resourced. • Missile transfer vans /warhead transfer vans require upgrades. • ICBM weapon system test sets under-funded; the coding system...Air Force’s Nuclear Mission D-1 Appendix D. Current B-52 Basing Status Barksdale AFB, LA 64 B-52Hs Minot AFB, ND 27 B-52Hs Edwards AFB, CA 3...Barksdale – 64 B-52s 2 BW (ACC) 15 TF; 24 CC; 7 BAI 53 WG (ACC) 2 Test Coded 917 WG (AFRC) 8 CC; 1 BAI 7 Unfunded AR Edwards - 3 B-52s 412 TW 2 Test
Activation of acetyl-coenzyme A carboxylase is involved in Taxol-induced ovarian cancer cell death
WU, JIANG; JI, FANG; DI, WEN; CHEN, HONGDUO; WAN, YINSHENG
2011-01-01
Acetyl-coenzyme A carboxylase (ACC) is an attractive target for research into the treatment of a variety of human diseases, including diabetes, obesity and cancer. Mounting evidence suggests that the inhibition of ACC induced of cancer cell apoptosis. However, whether the inhibition of ACC regulates apoptosis in CaOV3 cancer cells has yet to be addressed. This study investigated the cytotoxic mechanism of action of ACC inhibition. Results showed that 5-(tetradecyloxy)-2-furoic acid (TOFA), an ACC inhibitor, enhanced Taxol-induced CaOV3 human ovarian cancer cell apoptosis. Notably, when TOFA was administered as a monotherapy, it induced CaOV3 cell apoptosis. Pre-treatment with the EGFR inhibitor PD153035 was found to markedly enhance ACC phosphorylation, whereas AMP-activated protein kinase (AMPK) activator AICAR was found to marginally enhance ACC phosphorylation. Taken together, the data showed ACC is a potential novel molecular target of Taxol. Additionally, ACC inhibition partially contributed to the cytotoxic effect of Taxol in ovarian cancer cells. PMID:22866118
Activation of acetyl-coenzyme A carboxylase is involved in Taxol-induced ovarian cancer cell death.
Wu, Jiang; Ji, Fang; DI, Wen; Chen, Hongduo; Wan, Yinsheng
2011-05-01
Acetyl-coenzyme A carboxylase (ACC) is an attractive target for research into the treatment of a variety of human diseases, including diabetes, obesity and cancer. Mounting evidence suggests that the inhibition of ACC induced of cancer cell apoptosis. However, whether the inhibition of ACC regulates apoptosis in CaOV3 cancer cells has yet to be addressed. This study investigated the cytotoxic mechanism of action of ACC inhibition. Results showed that 5-(tetradecyloxy)-2-furoic acid (TOFA), an ACC inhibitor, enhanced Taxol-induced CaOV3 human ovarian cancer cell apoptosis. Notably, when TOFA was administered as a monotherapy, it induced CaOV3 cell apoptosis. Pre-treatment with the EGFR inhibitor PD153035 was found to markedly enhance ACC phosphorylation, whereas AMP-activated protein kinase (AMPK) activator AICAR was found to marginally enhance ACC phosphorylation. Taken together, the data showed ACC is a potential novel molecular target of Taxol. Additionally, ACC inhibition partially contributed to the cytotoxic effect of Taxol in ovarian cancer cells.
24 CFR 969.105 - Extension of ACC upon payment of operating subsidy.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Extension of ACC upon payment of... COMPLETION OF DEBT SERVICE § 969.105 Extension of ACC upon payment of operating subsidy. (a) ACC amendment... projects under a particular ACC for a PHA fiscal year beginning after the effective date of this part, the...
24 CFR 969.105 - Extension of ACC upon payment of operating subsidy.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Extension of ACC upon payment of... COMPLETION OF DEBT SERVICE § 969.105 Extension of ACC upon payment of operating subsidy. (a) ACC amendment... projects under a particular ACC for a PHA fiscal year beginning after the effective date of this part, the...
Chen, Jianguo; Jeppesen, Per Bendix; Nordentoft, Iver; Hermansen, Kjeld
2007-06-01
Chronic hyperglycemia is detrimental to pancreatic beta-cells, causing impaired insulin secretion and beta-cell turnover. The characteristic secretory defects are increased basal insulin secretion (BIS) and a selective loss of glucose-stimulated insulin secretion (GSIS). Several recent studies support the view that the acetyl-CoA carboxylase (ACC) plays a pivotal role for GSIS. We have shown that stevioside (SVS) enhances insulin secretion and ACC gene expression. Whether glucotoxicity influences ACC and whether this action can be counteracted by SVS are not known. To investigate this, we exposed isolated mouse islets as well as clonal INS-1E beta-cells for 48 h to 27 or 16.7 mM glucose, respectively. We found that 48-h exposure to high glucose impairs GSIS from mouse islets and INS-1E cells, an effect that is partly counteracted by SVS. The ACC dephosphorylation inhibitor okadaic acid (OKA, 10(-8) M), and 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR, 10(-4) M), an activator of 5'-AMP protein kinase that phosphorylates ACC, eliminated the beneficial effect of SVS. 5-Tetrade-cyloxy-2-furancarboxylic acid (TOFA), the specific ACC inhibitor, blocked the effect of SVS as well. During glucotoxity, ACC gene expression, ACC protein, and phosphorylated ACC protein were increased in INS-1E beta-cells. SVS pretreatment further increased ACC gene expression with strikingly elevated ACC activity and increased glucose uptake accompanied by enhanced GSIS. Our studies show that glucose is a potent stimulator of ACC and that SVS to some extent counteracts glucotoxicity via increased ACC activity. SVS possesses the potential to alleviate negative effects of glucotoxicity in beta-cells via a unique mechanism of action.
Webb, Christian A.; Olson, Elizabeth A.; Killgore, William D.S.; Pizzagalli, Diego A.; Rauch, Scott L.; Rosso, Isabelle M.
2018-01-01
Background Rostral and subgenual anterior cingulate cortex (rACC and sgACC) activity and, to a lesser extent, volume have been shown to predict depressive symptom improvement across different antidepressant treatments. This study extends prior work by examining whether rACC and/or sgACC morphology predicts treatment response to internet-based cognitive behavioral therapy (iCBT) for major depressive disorder (MDD). This is the first study to examine neural predictors of response to iCBT. Methods Hierarchical linear modeling tested whether pre-treatment rACC and sgACC volumes predicted depressive symptom improvement during a 6-session (10-week) randomized clinical trial of iCBT (n = 35) vs. a monitored attention control (MAC; n = 38). Analyses also tested whether pre-treatment rACC and sgACC volumes differed between patients who achieved depression remission versus those who did not remit. Results Larger pre-treatment right rACC volume was a significant predictor of greater depressive symptom improvement in iCBT, even when controlling for demographic (age, gender, race) and clinical (baseline depression, anhedonia and anxiety) variables previously linked to treatment response. In addition, pre-treatment right rACC volume was larger among iCBT patients whose depression eventually remitted relative to those who did not remit. Corresponding analyses in the MAC group and for the sgACC were not significant. Conclusions rACC volume prior to iCBT demonstrated incremental predictive validity beyond clinical and demographic variables previously found to predict symptom improvement. Such findings may help inform our understanding of the mediating anatomy of iCBT and, if replicated, may suggest neural targets to augment treatment response (e.g., via modulation of rACC function). ClinicalTrials.gov Identifier NCT01598922 PMID:29486867
Liu, Xun; Hairston, Jacqueline; Schrier, Madeleine; Fan, Jin
2011-01-01
To better understand the reward circuitry in human brain, we conducted activation likelihood estimation (ALE) and parametric voxel-based meta-analyses (PVM) on 142 neuroimaging studies that examined brain activation in reward-related tasks in healthy adults. We observed several core brain areas that participated in reward-related decision making, including the nucleus accumbens (NAcc), caudate, putamen, thalamus, orbitofrontal cortex (OFC), bilateral anterior insula, anterior (ACC) and posterior (PCC) cingulate cortex, as well as cognitive control regions in the inferior parietal lobule and prefrontal cortex (PFC). The NAcc was commonly activated by both positive and negative rewards across various stages of reward processing (e.g., anticipation, outcome, and evaluation). In addition, the medial OFC and PCC preferentially responded to positive rewards, whereas the ACC, bilateral anterior insula, and lateral PFC selectively responded to negative rewards. Reward anticipation activated the ACC, bilateral anterior insula, and brain stem, whereas reward outcome more significantly activated the NAcc, medial OFC, and amygdala. Neurobiological theories of reward-related decision making should therefore distributed and interrelated representations of reward valuation and valence assessment into account. PMID:21185861
Neurons in the Frontal Lobe Encode the Value of Multiple Decision Variables
Kennerley, Steven W.; Dahmubed, Aspandiar F.; Lara, Antonio H.; Wallis, Jonathan D.
2009-01-01
A central question in behavioral science is how we select among choice alternatives to obtain consistently the most beneficial outcomes. Three variables are particularly important when making a decision: the potential payoff, the probability of success, and the cost in terms of time and effort. A key brain region in decision making is the frontal cortex as damage here impairs the ability to make optimal choices across a range of decision types. We simultaneously recorded the activity of multiple single neurons in the frontal cortex while subjects made choices involving the three aforementioned decision variables. This enabled us to contrast the relative contribution of the anterior cingulate cortex (ACC), the orbito-frontal cortex, and the lateral prefrontal cortex to the decision-making process. Neurons in all three areas encoded value relating to choices involving probability, payoff, or cost manipulations. However, the most significant signals were in the ACC, where neurons encoded multiplexed representations of the three different decision variables. This supports the notion that the ACC is an important component of the neural circuitry underlying optimal decision making. PMID:18752411
Jackson, Stacey A. W.; Horst, Nicole K.; Pears, Andrew; Robbins, Trevor W.; Roberts, Angela C.
2016-01-01
Two learning mechanisms contribute to decision-making: goal-directed actions and the “habit” system, by which action-outcome and stimulus-response associations are formed, respectively. Rodent lesion studies and human neuroimaging have implicated both the medial prefrontal cortex (mPFC) and the orbitofrontal cortex (OFC) in the neural basis of contingency learning, a critical component of goal-directed actions, though some published findings are conflicting. We sought to reconcile the existing literature by comparing the effects of excitotoxic lesions of the perigenual anterior cingulate cortex (pgACC), a region of the mPFC, and OFC on contingency learning in the marmoset monkey using a touchscreen-based paradigm, in which the contingent relationship between one of a pair of actions and its outcome was degraded selectively. Both the pgACC and OFC lesion groups were insensitive to the contingency degradation, whereas the control group demonstrated selectively higher performance of the nondegraded action when compared with the degraded action. These findings suggest the pgACC and OFC are both necessary for normal contingency learning and therefore goal-directed behavior. PMID:27130662
Background/Question/Methods: Large river floodplains are poor nitrate pollution buffers when polluted groundwater moves beneath biogeochemically retentive zones prior to entering the main channel. However, in floodplain regions with extensive backwaters and organic carbon acc...
Brennan, Brian P; Tkachenko, Olga; Schwab, Zachary J; Juelich, Richard J; Ryan, Erin M; Athey, Alison J; Pope, Harrison G; Jenike, Michael A; Baker, Justin T; Killgore, William DS; Hudson, James I; Jensen, J Eric; Rauch, Scott L
2015-01-01
The anterior cingulate cortex is implicated in the neurobiology of obsessive–compulsive disorder (OCD). However, few studies have examined functional and neurochemical abnormalities specifically in the rostral subdivision of the ACC (rACC) in OCD patients. We used functional magnetic resonance imaging (fMRI) during an emotional counting Stroop task and single-voxel J-resolved proton magnetic resonance spectroscopy (1H-MRS) in the rACC to examine the function and neurochemistry of the rACC in individuals with OCD and comparison individuals without OCD. Between-group differences in rACC activation and glutamine/glutamate ratio (Gln/Glu), Glu, and Gln levels, as well as associations between rACC activation, Gln/Glu, Glu, Gln, behavioral, and clinical measures were examined using linear regression. In a sample of 30 participants with OCD and 29 age- and sex-matched participants without OCD, participants with OCD displayed significantly reduced rACC deactivation compared with those without OCD in response to OCD-specific words versus neutral words on the emotional counting Stroop task. However, Gln/Glu, Glu, and Gln in the rACC did not differ between groups nor was there an association between reduced rACC deactivation and Gln/Glu, Glu, or Gln in the OCD group. Taken together, these findings strengthen the evidence for rACC dysfunction in OCD, but weigh against an underlying association with abnormal rACC glutamatergic neurotransmission. PMID:25662837
24 CFR 941.305 - Technical processing and approval.
Code of Federal Regulations, 2011 CFR
2011-04-01
... shall notify the PHA in writing and shall forward to it for execution an ACC (or ACC amendment). If the PHA already has executed an ACC (or ACC amendment) for the entire reserved amount, HUD shall notify...
24 CFR 941.305 - Technical processing and approval.
Code of Federal Regulations, 2010 CFR
2010-04-01
... shall notify the PHA in writing and shall forward to it for execution an ACC (or ACC amendment). If the PHA already has executed an ACC (or ACC amendment) for the entire reserved amount, HUD shall notify...
Jalbrzikowski, Maria; Larsen, Bart; Hallquist, Michael N; Foran, William; Calabro, Finnegan; Luna, Beatriz
2017-10-01
Connectivity between the amygdala and ventromedial prefrontal cortex (vmPFC) is compromised in multiple psychiatric disorders, many of which emerge during adolescence. To identify to what extent the deviations in amygdala-vmPFC maturation contribute to the onset of psychiatric disorders, it is essential to characterize amygdala-vmPFC connectivity changes during typical development. Using an accelerated cohort longitudinal design (1-3 time points, 10-25 years old, n = 246), we characterized developmental changes of the amygdala-vmPFC subregion functional and structural connectivity using resting-state functional magnetic resonance imaging and diffusion-weighted imaging. Functional connectivity between the centromedial amygdala and rostral anterior cingulate cortex (rACC), anterior vmPFC, and subgenual cingulate significantly decreased from late childhood to early adulthood in male and female subjects. Age-associated decreases were also observed between the basolateral amygdala and the rACC. Importantly, these findings were replicated in a separate cohort (10-22 years old, n = 327). Similarly, structural connectivity, as measured by quantitative anisotropy, significantly decreased with age in the same regions. Functional connectivity between the centromedial amygdala and the rACC was associated with structural connectivity in these same regions during early adulthood (22-25 years old). Finally, a novel time-varying coefficient analysis showed that increased centromedial amygdala-rACC functional connectivity was associated with greater anxiety and depression symptoms during early adulthood, while increased structural connectivity in centromedial amygdala-anterior vmPFC white matter was associated with greater anxiety/depression during late childhood. Specific developmental periods of functional and structural connectivity between the amygdala and the prefrontal systems may contribute to the emergence of anxiety and depressive symptoms and may play a critical role in the emergence of psychiatric disorders in adolescence. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Kremer, Heidemarie; Lutz, Franz P C; McIntosh, Roger C; Dévieux, Jessy G; Ironson, Gail
2016-04-01
Resting EEGs of 40 people living with HIV (PLWH) on long-term antiretroviral treatment were examined for z-scored deviations from a healthy control (normative database) to examine the main and interaction effects of depression and gender. Regions of interest were frontal (alpha) and central (all bands) for interhemispheric asymmetries in quantitative EEGs and theta in the rostral anterior cingulate cortex (rACC) in low-resolution electromagnetic tomography (LORETA). Z-scored normed deviations of depressed PLWH, compared with nondepressed, showed right-dominant interhemispheric asymmetries in all regions. However, after adjusting for multiple testing, significance remained only central for theta, alpha, and beta. Reversed (left-dominant) frontal alpha asymmetry is a potential EEG marker of depression in the HIV negative population that was not reversed in depressive PLWH; however, corresponding with extant literature, gender had an effect on the size of frontal alpha asymmetry. The LORETA analysis revealed a trending interactional effect of depression and gender on theta activity in the rACC in Brodmann area 32. We found that compared to men, women had greater right-dominant frontal alpha-asymmetry and elevated theta activity in voxels of the rACC, which may indicate less likelihood of depression and a higher likelihood of response to antidepressants. In conclusion, subtle EEG deviations, such as right-dominant central theta, alpha, and beta asymmetries and theta activity in the rACC may mark HIV-related depressive symptoms and may predict the likelihood of response to antidepressants but gender effects need to be taken into account. Although this study introduced the use of LORETA to examine the neurophysiological correlates of negative affect in PLWH, further research is needed to assess the utility of this tool in diagnostics and treatment monitoring of depression in PLWH. © EEG and Clinical Neuroscience Society (ECNS) 2015.
Sex differences in neural responses to stress and alcohol context cues.
Seo, Dongju; Jia, Zhiru; Lacadie, Cheryl M; Tsou, Kristen A; Bergquist, Keri; Sinha, Rajita
2011-11-01
Stress and alcohol context cues are each associated with alcohol-related behaviors, yet neural responses underlying these processes remain unclear. This study investigated the neural correlates of stress and alcohol context cue experiences and examined sex differences in these responses. Using functional magnetic resonance imaging, brain responses were examined while 43 right-handed, socially drinking, healthy individuals (23 females) engaged in brief guided imagery of personalized stress, alcohol-cue, and neutral-relaxing scenarios. Stress and alcohol-cue exposure increased activity in the cortico-limbic-striatal circuit (P < 0.01, corrected), encompassing the medial prefrontal cortex (mPFC), orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), left anterior insula, striatum, and visuomotor regions (parietal and occipital lobe, and cerebellum). Activity in the left dorsal striatum increased during stress, while bilateral ventral striatum activity was evident during alcohol-cue exposure. Men displayed greater stress-related activations in the mPFC, rostral ACC, posterior insula, amygdala, and hippocampus than women, whereas women showed greater alcohol-cue-related activity in the superior and middle frontal gyrus (SFG/MFG) than men. Stress-induced anxiety was positively associated with activity in emotion-modulation regions, including the medial OFC, ventromedial PFC, left superior-mPFC, and rostral ACC in men, but in women with activation in the SFG/MFG, regions involved in cognitive processing. Alcohol craving was significantly associated with the striatum (encompassing dorsal, and ventral) in men, supporting its involvement in alcohol "urge" in healthy men. These results indicate sex differences in neural processing of stress and alcohol-cue experiences and have implications for sex-specific vulnerabilities to stress- and alcohol-related psychiatric disorders. Copyright © 2010 Wiley-Liss, Inc.
Structural neural correlates of multitasking: A voxel-based morphometry study.
Zhang, Rui-Ting; Yang, Tian-Xiao; Wang, Yi; Sui, Yuxiu; Yao, Jingjing; Zhang, Chen-Yuan; Cheung, Eric F C; Chan, Raymond C K
2016-12-01
Multitasking refers to the ability to organize assorted tasks efficiently in a short period of time, which plays an important role in daily life. However, the structural neural correlates of multitasking performance remain unclear. The present study aimed at exploring the brain regions associated with multitasking performance using global correlation analysis. Twenty-six healthy participants first underwent structural brain scans and then performed the modified Six Element Test, which required participants to attempt six subtasks in 10 min while obeying a specific rule. Voxel-based morphometry of the whole brain was used to detect the structural correlates of multitasking ability. Grey matter volume of the anterior cingulate cortex (ACC) was positively correlated with the overall performance and time monitoring in multitasking. In addition, white matter volume of the anterior thalamic radiation (ATR) was also positively correlated with time monitoring during multitasking. Other related brain regions associated with multitasking included the superior frontal gyrus, the inferior occipital gyrus, the lingual gyrus, and the inferior longitudinal fasciculus. No significant correlation was found between grey matter volume of the prefrontal cortex (Brodmann Area 10) and multitasking performance. Using a global correlation analysis to examine various aspects of multitasking performance, this study provided new insights into the structural neural correlates of multitasking ability. In particular, the ACC was identified as an important brain region that played both a general and a specific time-monitoring role in multitasking, extending the role of the ACC from lesioned populations to healthy populations. The present findings also support the view that the ATR may influence multitasking performance by affecting time-monitoring abilities. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
Aarts, Esther; Roelofs, Ardi; van Turennout, Miranda
2008-04-30
Previous studies have found no agreement on whether anticipatory activity in the anterior cingulate cortex (ACC) reflects upcoming conflict, error likelihood, or actual control adjustments. Using event-related functional magnetic resonance imaging, we investigated the nature of preparatory activity in the ACC. Informative cues told the participants whether an upcoming target would or would not involve conflict in a Stroop-like task. Uninformative cues provided no such information. Behavioral responses were faster after informative than after uninformative cues, indicating cue-based adjustments in control. ACC activity was larger after informative than uninformative cues, as would be expected if the ACC is involved in anticipatory control. Importantly, this activation in the ACC was observed for informative cues even when the information conveyed by the cue was that the upcoming target evokes no response conflict and has low error likelihood. This finding demonstrates that the ACC is involved in anticipatory control processes independent of upcoming response conflict or error likelihood. Moreover, the response of the ACC to the target stimuli was critically dependent on whether the cue was informative or not. ACC activity differed among target conditions after uninformative cues only, indicating ACC involvement in actual control adjustments. Together, these findings argue strongly for a role of the ACC in anticipatory control independent of anticipated conflict and error likelihood, and also show that such control can eliminate conflict-related ACC activity during target processing. Models of frontal cortex conflict-detection and conflict-resolution mechanisms require modification to include consideration of these anticipatory control properties of the ACC.
Hodson, Mark E; Benning, Liane G; Demarchi, Bea; Penkman, Kirsty E H; Rodriguez-Blanco, Juan D; Schofield, Paul F; Versteegh, Emma A A
Many biominerals form from amorphous calcium carbonate (ACC), but this phase is highly unstable when synthesised in its pure form inorganically. Several species of earthworm secrete calcium carbonate granules which contain highly stable ACC. We analysed the milky fluid from which granules form and solid granules for amino acid (by liquid chromatography) and functional group (by Fourier transform infrared (FTIR) spectroscopy) compositions. Granule elemental composition was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and electron microprobe analysis (EMPA). Mass of ACC present in solid granules was quantified using FTIR and compared to granule elemental and amino acid compositions. Bulk analysis of granules was of powdered bulk material. Spatially resolved analysis was of thin sections of granules using synchrotron-based μ-FTIR and EMPA electron microprobe analysis. The milky fluid from which granules form is amino acid-rich (≤ 136 ± 3 nmol mg -1 (n = 3; ± std dev) per individual amino acid); the CaCO 3 phase present is ACC. Even four years after production, granules contain ACC. No correlation exists between mass of ACC present and granule elemental composition. Granule amino acid concentrations correlate well with ACC content (r ≥ 0.7, p ≤ 0.05) consistent with a role for amino acids (or the proteins they make up) in ACC stabilisation. Intra-granule variation in ACC (RSD = 16%) and amino acid concentration (RSD = 22-35%) was high for granules produced by the same earthworm. Maps of ACC distribution produced using synchrotron-based μ-FTIR mapping of granule thin sections and the relative intensity of the ν 2 : ν 4 peak ratio, cluster analysis and component regression using ACC and calcite standards showed similar spatial distributions of likely ACC-rich and calcite-rich areas. We could not identify organic peaks in the μ-FTIR spectra and thus could not determine whether ACC-rich domains also had relatively high amino acid concentrations. No correlation exists between ACC distribution and elemental concentrations determined by EMPA. ACC present in earthworm CaCO 3 granules is highly stable. Our results suggest a role for amino acids (or proteins) in this stability. We see no evidence for stabilisation of ACC by incorporation of inorganic components. Graphical abstractSynchrotron-based μ-FTIR mapping was used to determine the spatial distribution of amorphous calcium carbonate in earthworm-produced CaCO 3 granules.
Kovacevic, Sanja; Azma, Sheeva; Irimia, Andrei; Sherfey, Jason; Halgren, Eric; Marinkovic, Ksenija
2012-01-01
Prior neuroimaging evidence indicates that decision conflict activates medial and lateral prefrontal and parietal cortices. Theoretical accounts of cognitive control highlight anterior cingulate cortex (ACC) as a central node in this network. However, a better understanding of the relative primacy and functional contributions of these areas to decision conflict requires insight into the neural dynamics of successive processing stages including conflict detection, response selection and execution. Moderate alcohol intoxication impairs cognitive control as it interferes with the ability to inhibit dominant, prepotent responses when they are no longer correct. To examine the effects of moderate intoxication on successive processing stages during cognitive control, spatio-temporal changes in total event-related theta power were measured during Stroop-induced conflict. Healthy social drinkers served as their own controls by participating in both alcohol (0.6 g/kg ethanol for men, 0.55 g/kg women) and placebo conditions in a counterbalanced design. Anatomically-constrained magnetoencephalography (aMEG) approach was applied to complex power spectra for theta (4-7 Hz) frequencies. The principal generator of event-related theta power to conflict was estimated to ACC, with contributions from fronto-parietal areas. The ACC was uniquely sensitive to conflict during both early conflict detection, and later response selection and execution stages. Alcohol attenuated theta power to conflict across successive processing stages, suggesting that alcohol-induced deficits in cognitive control may result from theta suppression in the executive network. Slower RTs were associated with attenuated theta power estimated to ACC, indicating that alcohol impairs motor preparation and execution subserved by the ACC. In addition to their relevance for the currently prevailing accounts of cognitive control, our results suggest that alcohol-induced impairment of top-down strategic processing underlies poor self-control and inability to refrain from drinking.
Broadband vehicle-to-vehicle communication using an extended autonomous cruise control sensor
NASA Astrophysics Data System (ADS)
Heddebaut, M.; Rioult, J.; Ghys, J. P.; Gransart, Ch; Ambellouis, S.
2005-06-01
For several years road vehicle autonomous cruise control (ACC) systems as well as anti-collision radar have been developed. Several manufacturers currently sell this equipment. The current generation of ACC sensors only track the first preceding vehicle to deduce its speed and position. These data are then used to compute, manage and optimize a safety distance between vehicles, thus providing some assistance to car drivers. However, in real conditions, to elaborate and update a real time driving solution, car drivers use information about speed and position of preceding and following vehicles. This information is essentially perceived using the driver's eyes, binocular stereoscopic vision performed through the windscreens and rear-view mirrors. Furthermore, within a line of vehicles, the frontal road perception of the first vehicle is very particular and highly significant. Currently, all these available data remain strictly on-board the vehicle that has captured the perception information and performed these measurements. To get the maximum effectiveness of all these approaches, we propose that this information be shared in real time with the following vehicles, within the convoy. On the basis of these considerations, this paper technically explores a cost-effective solution to extend the basic ACC sensor function in order to simultaneously provide a vehicle-to-vehicle radio link. This millimetre wave radio link transmits relevant broadband perception data (video, localization...) to following vehicles, along the line of vehicles. The propagation path between the vehicles uses essentially grazing angles of incidence of signals over the road surface including millimetre wave paths beneath the cars.
Inventory of File gfs.t06z.smartguam06.tm00.grib2
(0=sea, 1=land) [Proportion] 009 surface APCP 3-6 hour acc Total Precipitation [kg/m^2] 010 surface ] 020 surface TMAX 3-6 hour acc Maximum Temperature [K] 021 surface TMIN 3-6 hour acc Minimum Temperature [K] 022 surface MAXRH 3-6 hour acc Maximum Relative Humidity [%] 023 surface MINRH 3-6 hour acc
Wang, Tzann-Wei; Arteca, Richard N.
1992-01-01
Low O2 conditions were obtained by flowing N2 through the solution in which the tomato plants (Lycopersicon esculentum Mill cv Heinz 1350) were growing. Time course experiments revealed that low O2 treatments stimulated 1-aminocyclopropane-1-carboxylate (ACC) synthase production in the roots and leaves. After the initiation of low O2 conditions, ACC synthase activity and ACC content in the roots increased and reached a peak after 12 and 20 hours, respectively. The conversion of ACC to ethylene in the roots was inhibited by low levels of O2, and ACC was apparently transported to the leaves where it was converted to ethylene. ACC synthase activity in the leaves was also stimulated by low O2 treatment to the roots, reaching a peak after 24 hours. ACC synthase levels were enhanced by cobalt chloride and aminooxyacetic acid (AOA), although they inhibited ethylene production. Cobalt chloride enhanced ACC synthase only in combination with low O2 conditions in the roots. Under aeration, AOA stimulated ACC synthase activity in both the roots and leaves. However, in combination with low O2 conditions, AOA caused a stimulation in ACC synthase activity in the leaves and no effect in the roots. PMID:16668654
Reliability and Validity of Two Self-report Measures to Assess Sedentary Behavior in Older Adults
Gennuso, Keith P.; Matthews, Charles E.; Colbert, Lisa H.
2015-01-01
Background The purpose of this study was to examine the reliability and validity of two currently available physical activity surveys for assessing time spent in sedentary behavior (SB) in older adults. Methods Fifty-eight adults (≥65 years) completed the Yale Physical Activity Survey for Older Adults (YPAS) and Community Health Activities Model Program for Seniors (CHAMPS) before and after a 10-day period during which they wore an ActiGraph accelerometer (ACC). Intraclass correlation coefficients (ICC) examined test-retest reliability. Overall percent agreement and a kappa statistic examined YPAS validity. Lin’s concordance correlation, Pearson correlation, and Bland-Altman analysis examined CHAMPS validity. Results Both surveys had moderate test-retest reliability (ICC: YPAS=0.59 (P<0.001), CHAMPS=0.64 (P<0.001)) and significantly underestimated SB time. Agreement between YPAS and ACC was low (κ=−0.0003); however, there was a linear increase (P< 0.01) in ACC-derived SB time across YPAS response categories. There was poor agreement between ACC-derived SB and CHAMPS (Lin’s r=0.005; 95% CI, −0.010 to 0.020), and no linear trend across CHAMPS quartiles (p=0.53). Conclusions Neither of the surveys should be used as the sole measure of SB in a study; though the YPAS has the ability to rank individuals, providing it with some merit for use in correlational SB research. PMID:25110344
Kawai, Takashi; Yamada, Hiroshi; Sato, Nobuya; Takada, Masahiko; Matsumoto, Masayuki
2018-05-02
The dorsal anterior cingulate cortex (dACC) plays crucial roles in monitoring the outcome of a choice and adjusting a subsequent choice behavior based on the outcome information. In the present study, we investigated how different types of dACC neurons, that is, putative pyramidal neurons and putative inhibitory interneurons, contribute to these processes. We analyzed single-unit database obtained from the dACC in monkeys performing a reversal learning task. The monkey was required to adjust choice behavior from past outcome experiences. Depending on their action potential waveforms, the recorded neurons were classified into putative pyramidal neurons and putative inhibitory interneurons. We found that these neurons do not equally contribute to outcome monitoring and behavioral adjustment. Although both neuron types evenly responded to the current outcome, a larger proportion of putative inhibitory interneurons than putative pyramidal neurons stored the information about the past outcome. The putative inhibitory interneurons further represented choice-related signals more frequently, such as whether the monkey would shift the last choice to an alternative at the next choice opportunity. Our findings suggest that putative inhibitory interneurons, which are thought not to project to brain areas outside the dACC, preferentially transmit signals that would adjust choice behavior based on past outcome experiences.
Pathways of basal meltwater from Antarctic ice shelves: A model study
NASA Astrophysics Data System (ADS)
Kusahara, Kazuya; Hasumi, Hiroyasu
2014-09-01
We investigate spreading pathways of basal meltwater released from all Antarctic ice shelves using a circumpolar coupled ice shelf-sea ice-ocean model that reproduces major features of the Southern Ocean circulation, including the Antarctic Circumpolar Current (ACC). Several independent virtual tracers are used to identify detailed pathways of basal meltwaters. The spreading pathways of the meltwater tracers depend on formation sites, because the meltwaters are transported by local ambient ocean circulation. Meltwaters from ice shelves in the Weddell and Amundsen-Bellingshausen Seas in surface/subsurface layers are effectively advected to lower latitudes with the ACC. Although a large portion of the basal meltwaters is present in surface and subsurface layers, a part of the basal meltwaters penetrates into the bottom layer through active dense water formation along the Antarctic coastal margins. The signals at the seafloor extend along the topography, showing a horizontal distribution similar to the observed spreading of Antarctic Bottom Water. Meltwaters originating from ice shelves in the Weddell and Ross Seas and in the Indian sector significantly contribute to the bottom signals. A series of numerical experiments in which thermodynamic interaction between the ice shelf and ocean is neglected regionally demonstrates that the basal meltwater of each ice shelf impacts sea ice and/or ocean thermohaline circulation in the Southern Ocean. This article was corrected on 10 OCT 2014. See the end of the full text for details.
Piai, Vitória; Roelofs, Ardi; Acheson, Daniel J.; Takashima, Atsuko
2013-01-01
Accumulating evidence suggests that some degree of attentional control is required to regulate and monitor processes underlying speaking. Although progress has been made in delineating the neural substrates of the core language processes involved in speaking, substrates associated with regulatory and monitoring processes have remained relatively underspecified. We report the results of an fMRI study examining the neural substrates related to performance in three attention-demanding tasks varying in the amount of linguistic processing: vocal picture naming while ignoring distractors (picture-word interference, PWI); vocal color naming while ignoring distractors (Stroop); and manual object discrimination while ignoring spatial position (Simon task). All three tasks had congruent and incongruent stimuli, while PWI and Stroop also had neutral stimuli. Analyses focusing on common activation across tasks identified a portion of the dorsal anterior cingulate cortex (ACC) that was active in incongruent trials for all three tasks, suggesting that this region subserves a domain-general attentional control function. In the language tasks, this area showed increased activity for incongruent relative to congruent stimuli, consistent with the involvement of domain-general mechanisms of attentional control in word production. The two language tasks also showed activity in anterior-superior temporal gyrus (STG). Activity increased for neutral PWI stimuli (picture and word did not share the same semantic category) relative to incongruent (categorically related) and congruent stimuli. This finding is consistent with the involvement of language-specific areas in word production, possibly related to retrieval of lexical-semantic information from memory. The current results thus suggest that in addition to engaging language-specific areas for core linguistic processes, speaking also engages the ACC, a region that is likely implementing domain-general attentional control. PMID:24368899
NASA Astrophysics Data System (ADS)
Asdar, S.; Deshayes, J.; Ansorge, I. J.
2016-02-01
The sub-Antarctic Prince Edward Islands (PEI) (47°S,38°E) are classified as isolated, hostile, impoverished regions, in which the terrestrial and marine ecosystems are relatively simple and extremely sensitive to perturbations. Their location between the Sub-Antarctic Front (SAF) and the Antarctic Polar Front (APF), bordering the Antarctic Circumpolar Current (ACC) provides an ideal natural laboratory for studying how organisms, ecological processes and ecosystems respond to a changing ocean climate in the Southern Ocean. Recent studies have proposed that climate changes reported at the PEI may correspond in time to a southward shift of the ACC and in particular of the SAF. This southward migration in the geographic position is likely to coincide with dramatic changes in the distribution of species and total productivity of this region. This study focuses on the inter-comparison of observations available at these islands. Using spectral analysis which is a study of the frequency domain characteristics of a process, we first determine the dominant characteristics of both the temporal and spatial variability of physical and biogeochemical properties. In doing so the authors are able to determine whether and how these indices of variability interact with one another in order to understand better the mechanisms underpinning this variability, i.e. the seasonal zonal migrations associated with the SAF. Additionally, we include in our analysis recent data from 2 ADCP moorings deployed between the islands from 2014 to 2015. These in-situ observations of circulation and hydrography in the vicinity of the islands provide a unique opportunity to establish a better understanding of how large scale climatic variability may impact local conditions, and more importantly its influence on the fragile ecosystem surrounding the PEI.
ERIC Educational Resources Information Center
Jacobs, Jim
2013-01-01
Just as good community colleges pivot to mirror the needs of their local communities, the multistate Auto Communities Consortium (ACC) continues to evolve to counteract the challenges encountered by employers in its service region. Established in 2010 to address pervasive economic losses faced by communities whose major employers were auto…
Genaro, Karina; Fabris, Débora; Arantes, Ana L. F.; Zuardi, Antônio W.; Crippa, José A. S.; Prado, Wiliam A.
2017-01-01
Background: Pain involves different brain regions and is critically determined by emotional processing. Among other areas, the rostral anterior cingulate cortex (rACC) is implicated in the processing of affective pain. Drugs that interfere with the endocannabinoid system are alternatives for the management of clinical pain. Cannabidiol (CBD), a phytocannabinoid found in Cannabis sativa, has been utilized in preclinical and clinical studies for the treatment of pain. Herein, we evaluate the effects of CBD, injected either systemically or locally into the rACC, on mechanical allodynia in a postoperative pain model and on the negative reinforcement produced by relief of spontaneous incision pain. Additionally, we explored whether CBD underlies the reward of pain relief after systemic or rACC injection. Methods and Results: Male Wistar rats were submitted to a model of incision pain. All rats had mechanical allodynia, which was less intense after intraperitoneal CBD (3 and 10 mg/kg). Conditioned place preference (CPP) paradigm was used to assess negative reinforcement. Intraperitoneal CBD (1 and 3 mg/kg) inverted the CPP produced by peripheral nerve block even at doses that do not change mechanical allodynia. CBD (10 to 40 nmol/0.25 μL) injected into the rACC reduced mechanical allodynia in a dose-dependent manner. CBD (5 nmol/0.25 μL) did not change mechanical allodynia, but reduced peripheral nerve block-induced CPP, and the higher doses inverted the CPP. Additionally, CBD injected systemically or into the rACC at doses that did not change the incision pain evoked by mechanical stimulation significantly produced CPP by itself. Therefore, a non-rewarding dose of CBD in sham-incised rats becomes rewarding in incised rats, presumably because of pain relief or reduction of pain aversiveness. Conclusion: The study provides evidence that CBD influences different dimensions of the response of rats to a surgical incision, and the results establish the rACC as a brain area from which CBD evokes antinociceptive effects in a manner similar to the systemic administration of CBD. In addition, the study gives further support to the notion that the sensorial and affective dimensions of pain may be differentially modulated by CBD. PMID:28680401
Liver resection for metastases of tracheal adenoid cystic carcinoma: Report of two cases.
Hashimoto, Shintaro; Sumida, Yorihisa; Tobinaga, Shuichi; Wada, Hideo; Wakata, Kouki; Nonaka, Takashi; Kunizaki, Masaki; Hidaka, Shigekazu; Kinoshita, Naoe; Sawai, Terumitsu; Nagayasu, Takeshi
2018-05-16
Tracheal adenoid cystic carcinoma (ACC) is rare and accounts for <1% of all lung cancers. Although ACC is classified as a low-grade tumor, metastases are frequently identified in the late period. Extrapulmonary metastases are rare, and their resection has rarely been reported. Case 1: A 77-year-old man underwent tracheal resection for ACC with postoperative radiation (60 Gy) 14 years before (at the age of 63). He underwent two subsequent pulmonary resections for metastases. Fourteen years after the first operation, he underwent extended right posterior segmentectomy with resection of segment IV and radiofrequency ablation for metastases of ACC to the liver. He was diagnosed with metastases to the kidney with peritoneal dissemination 4 years after the liver resection and died of pneumonia 2 years later. Case 2: A 53-year-old woman underwent a two-stage operation involving tracheal resection for ACC and partial resection of liver segments II and V for metastases of ACC to the liver. The tracheal margin was histopathologically positive. Postoperative radiation was performed, and she was tumor-free for 10 months after the liver resection. Complete resection of tracheal ACC provides better survival. Radiotherapy is also recommended. However, the optimal treatment for metastases of ACC is unclear, especially because liver resection for metastases of tracheal ACC is rarely reported. Our two cases of metastases of tracheal ACC were surgically managed with good outcomes. Liver resection for metastases of tracheal ACC may contribute to long survival. Copyright © 2018. Published by Elsevier Ltd.
Pagidipati, Neha J; Navar, Ann Marie; Mulder, Hillary; Sniderman, Allan D; Peterson, Eric D; Pencina, Michael J
2017-04-18
There are important differences among guideline recommendations for using statin therapy in primary prevention. New recommendations from the US Preventive Services Task Force (USPSTF) emphasize therapy based on the presence of 1 or more cardiovascular disease (CVD) risk factors and a 10-year global CVD risk of 10% or greater. To determine the difference in eligibility for primary prevention statin treatment among US adults, assuming full application of USPSTF recommendations compared with the American College of Cardiology/American Heart Association (ACC/AHA) guidelines. National Health and Nutrition Examination Survey (NHANES) data (2009-2014) were used to assess statin eligibility under the 2016 USPSTF recommendations vs the 2013 ACC/AHA cholesterol guidelines among a nationally representative sample of 3416 US adults aged 40 to 75 years with fasting lipid data and triglyceride levels of 400 mg/dL or less, without prior CVD. The 2016 USPSTF recommendations vs 2013 ACC/AHA guidelines. Eligibility for primary prevention statin therapy. Among the US primary prevention population represented by 3416 individuals in NHANES, the median weighted age was 53 years (interquartile range, 46-61), and 53% (95% CI, 52%-55%) were women. Along with the 21.5% (95% CI, 19.3%-23.7%) of patients who reported currently taking lipid-lowering medication, full implementation of the USPSTF recommendations would be associated with initiation of statin therapy in an additional 15.8% (95% CI, 14.0%-17.5%) of patients, compared with an additional 24.3% (95% CI, 22.3%-26.3%) of patients who would be recommended for statin initiation under full implementation of the 2013 ACC/AHA guidelines. Among the 8.9% of individuals in the primary prevention population who would be recommended for statins by ACC/AHA guidelines but not by USPSTF recommendations, 55% would be adults aged 40 to 59 years with a mean 30-year cardiovascular risk greater than 30%, and 28% would have diabetes. In this sample of US adults from 2009-2014, adherence to the 2016 USPSTF recommendations for statin therapy, compared with the 2013 ACC/AHA guidelines, could lead to a lower number of individuals recommended for primary prevention statin therapy, including many younger adults with high mean long-term CVD risk.
24 CFR 969.107 - HUD approval of demolition or disposition before ACC expiration.
Code of Federal Regulations, 2010 CFR
2010-04-01
... disposition before ACC expiration. 969.107 Section 969.107 Housing and Urban Development Regulations Relating... before ACC expiration. This part is not intended to preclude or restrict the demolition or disposition of... before the ACC Expiration Date. ...
Li, Yan; Jakary, Angela; Gillung, Erin; Eisendrath, Stuart; Nelson, Sarah J; Mukherjee, Pratik; Luks, Tracy
2016-06-01
Our aim was to evaluate differences in metabolite levels between unmedicated patients with major depressive disorder (MDD) and healthy controls, to assess changes in metabolites in patients after they completed an 8-week course of mindfulness-based cognitive therapy (MBCT), and to exam the correlation between metabolites and depression severity. Sixteen patients with MDD and ten age- and gender-matched healthy controls were studied using 3D short echo-time (20 ms) magnetic resonance spectroscopic imaging (MRSI) at 7 Tesla. Relative metabolite ratios were estimated in five regions of interest corresponding to insula, anterior cingulate cortex (ACC), caudate, putamen, and thalamus. In all cases, MBCT reduced severity of depression. The ratio of total choline-containing compounds/total creatine (tCr) in the right caudate was significantly increased compared to that in healthy controls, while ratios of N-acetyl aspartate (NAA)/tCr in the left ACC, myo-inositol/tCr in the right insula, and glutathione/tCr in the left putamen were significantly decreased. At baseline, the severity of depression was negatively correlated with my-inositol/tCr in the left insula and putamen. The improvement in depression severity was significantly associated with changes in NAA/tCr in the left ACC. This study has successfully evaluated regional differences in metabolites for patients with MDD who received MBCT treatment and in controls using 7 Tesla MRSI.
Neurocircuitry underlying risk and resilience to social anxiety disorder
Clauss, Jacqueline A.; Avery, Suzanne N.; VanDerKlok, Ross M.; Rogers, Baxter P.; Cowan, Ronald L.; Benningfield, Margaret M.; Blackford, Jennifer Urbano
2015-01-01
Background Almost half of children with an inhibited temperament will develop social anxiety disorder by late adolescence. Importantly, this means that half of children with an inhibited temperament will not develop social anxiety disorder. Studying adults with an inhibited temperament provides a unique opportunity to identify neural signatures of both risk and resilience to social anxiety disorder. Methods Functional MRI was used to measure brain activation during the anticipation of viewing fear faces in 34 young adults (17 inhibited, 17 uninhibited). To identify neural signatures of risk, we tested for group differences in functional activation and connectivity in regions implicated in social anxiety disorder, including the prefrontal cortex, amygdala, and insula. To identify neural signatures of resilience, we tested correlations between brain activation and both emotion regulation and social anxiety scores. Results Inhibited subjects had greater activation of a prefrontal network when anticipating viewing fear faces, relative to uninhibited subjects. No group differences were identified in the amygdala. Inhibited subjects had more negative connectivity between the rostral anterior cingulate cortex (ACC) and the bilateral amygdala. Within the inhibited group, those with fewer social anxiety symptoms and better emotion regulation skills had greater ACC activation and greater functional connectivity between the ACC and amygdala. Conclusions These finding suggest that engaging regulatory prefrontal regions during anticipation may be a protective factor, or putative neural marker of resilience, in high-risk individuals. Cognitive training targeting prefrontal cortex function may provide protection against anxiety, especially in high-risk individuals, such as those with inhibited temperament. PMID:24753211
Onoda, Keiichi; Okamoto, Yasumasa; Nakashima, Ken'ichiro; Nittono, Hiroshi; Ura, Mitsuhiro; Yamawaki, Shigeto
2009-01-01
People feel psychological pain when they are excluded, and this pain is often attenuated when emotional support is received. It is therefore likely that a specific neural mechanism underlies the detection of social exclusion. Similarly, specific neural mechanisms may underlie the beneficial effects of emotional support. Although neuroimaging researchers have recently examined the neural basis of social pain, there is presently no agreement as to which part of the anterior cingulate cortex (ACC) is involved in the perception and modulation of social pain. We hypothesized that activity in those brain regions that are associated with social pain would be correlated with decrements in social pain induced by emotional support. To examine the effects of emotional support on social pain caused by exclusion, we conducted an fMRI study in which participants played a virtual ball-tossing game. Participants were initially included and later excluded from the game. In the latter half of the session from which participants were excluded, participants received emotionally supportive text messages. We found that emotional support led to increased activity in the left lateral/medial prefrontal cortices and some temporal regions. Those individuals who experienced greater attenuation of social pain exhibited lower ventral ACC and higher left lateral prefrontal cortex activation. These results suggest that the ventral ACC underlies social pain, and that emotional support enhances prefrontal cortex activity, which in turn may lead to a weakened affective response.
Prostate-Specific Membrane Antigen Is a Potential Antiangiogenic Target in Adrenocortical Carcinoma.
Crowley, Michael J P; Scognamiglio, Theresa; Liu, Yi-Fang; Kleiman, David A; Beninato, Toni; Aronova, Anna; Liu, He; Jhanwar, Yuliya S; Molina, Ana; Tagawa, Scott T; Bander, Neil H; Zarnegar, Rasa; Elemento, Olivier; Fahey, Thomas J
2016-03-01
Adrenocortical carcinoma (ACC) is a rare tumor type with a poor prognosis and few therapeutic options. Assess prostate-specific membrane antigen (PSMA) expression as a potential novel therapeutic target for ACC. Expression of PSMA was evaluated in benign and malignant adrenal tumors and 1 patient with metastatic ACC. This study took place at a tertiary referral center. Fifty adrenal samples were evaluated, including 16 normal adrenal glands, 16 adrenocortical adenomas, 15 primary ACC, and 3 ACC metastases. Demographics, PSMA expression levels via real-time quantitative polymerase chain reaction and immunohistochemistry and whole-body positron emission tomography-computed tomography standardized uptake values for 1 patient. qPCR demonstrated an elevated level of PSMA in ACC relative to all benign tissues (P < .05). Immunohistochemistry localized PSMA expression to the neovasculature of ACC and confirmed overexpression of PSMA in ACC relative to benign tissues both in intensity and percentage of vessels stained (78% of ACC, 0% of normal adrenal, and 3.27% of adenoma-associated neovasculature; P < .001). Those with more than 25% PSMA-positive vessels were 33 times more likely to be malignant than benign (odds ratio, P < .001). Whole-body positron emission tomography-computed tomography imaging showed targeting of anti-PSMA Zr89-J591 to 5/5 of the patient's multiple lung masses with an average measurement of 3.49 ± 1.86 cm and a standardized uptake value of 1.4 ± 0.65 relative to blood pool at 0.8 standardized uptake value. PSMA is significantly overexpressed in ACC neovasculature when compared with normal and benign adrenal tumors. PSMA expression can be used to image ACC metastases in vivo and may be considered as a potential diagnostic and therapeutic target in ACC.
Driver's behavioral adaptation to adaptive cruise control (ACC): the case of speed and time headway.
Bianchi Piccinini, Giulio Francesco; Rodrigues, Carlos Manuel; Leitão, Miguel; Simões, Anabela
2014-06-01
The Adaptive Cruise Control is an Advanced Driver Assistance System (ADAS) that allows maintaining given headway and speed, according to settings pre-defined by the users. Despite the potential benefits associated to the utilization of ACC, previous studies warned against negative behavioral adaptations that might occur while driving with the system activated. Unfortunately, up to now, there are no unanimous results about the effects induced by the usage of ACC on speed and time headway to the vehicle in front. Also, few studies were performed including actual users of ACC among the subjects. This research aimed to investigate the effect of the experience gained with ACC on speed and time headway for a group of users of the system. In addition, it explored the impact of ACC usage on speed and time headway for ACC users and regular drivers. A matched sample driving simulator study was planned as a two-way (2×2) repeated measures mixed design, with the experience with ACC as between-subjects factor and the driving condition (with ACC and manually) as within-subjects factor. The results show that the usage of ACC brought a small but not significant reduction of speed and, especially, the maintenance of safer time headways, being the latter result greater for ACC users, probably as a consequence of their experience in using the system. The usage of ACC did not cause any negative behavioral adaptations to the system regarding speed and time headway. Based on this research work, the Adaptive Cruise Control showed the potential to improve road safety for what concerns the speed and the time headway maintained by the drivers. The speed of the surrounding traffic and the minimum time headway settable through the ACC seem to have an important effect on the road safety improvement achievable with the system. Copyright © 2014 Elsevier Ltd. All rights reserved.
24 CFR 985.109 - Default under the Annual Contributions Contract (ACC).
Code of Federal Regulations, 2011 CFR
2011-04-01
... Contributions Contract (ACC). 985.109 Section 985.109 Housing and Urban Development REGULATIONS RELATING TO... § 985.109 Default under the Annual Contributions Contract (ACC). HUD may determine that an PHA's failure... required by HUD constitutes a default under the ACC. ...
24 CFR 985.109 - Default under the Annual Contributions Contract (ACC).
Code of Federal Regulations, 2010 CFR
2010-04-01
... Contributions Contract (ACC). 985.109 Section 985.109 Housing and Urban Development Regulations Relating to... § 985.109 Default under the Annual Contributions Contract (ACC). HUD may determine that an PHA's failure... required by HUD constitutes a default under the ACC. ...
Sabne, Amit J.; Sakdhnagool, Putt; Lee, Seyong; ...
2015-07-13
Accelerator-based heterogeneous computing is gaining momentum in the high-performance computing arena. However, the increased complexity of heterogeneous architectures demands more generic, high-level programming models. OpenACC is one such attempt to tackle this problem. Although the abstraction provided by OpenACC offers productivity, it raises questions concerning both functional and performance portability. In this article, the authors propose HeteroIR, a high-level, architecture-independent intermediate representation, to map high-level programming models, such as OpenACC, to heterogeneous architectures. They present a compiler approach that translates OpenACC programs into HeteroIR and accelerator kernels to obtain OpenACC functional portability. They then evaluate the performance portability obtained bymore » OpenACC with their approach on 12 OpenACC programs on Nvidia CUDA, AMD GCN, and Intel Xeon Phi architectures. They study the effects of various compiler optimizations and OpenACC program settings on these architectures to provide insights into the achieved performance portability.« less
Increased error-related thalamic activity during early compared to late cocaine abstinence.
Li, Chiang-Shan R; Luo, Xi; Sinha, Rajita; Rounsaville, Bruce J; Carroll, Kathleen M; Malison, Robert T; Ding, Yu-Shin; Zhang, Sheng; Ide, Jaime S
2010-06-01
Altered cognitive control is implicated in the shaping of cocaine dependence. One of the key component processes of cognitive control is error monitoring. Our previous imaging work highlighted greater activity in distinct cortical and subcortical regions including the dorsal anterior cingulate cortex (dACC), thalamus and insula when participants committed an error during the stop signal task (Li et al., 2008b). Importantly, dACC, thalamic and insular activity has been associated with drug craving. One hypothesis is that the intense interoceptive activity during craving prevents these cerebral structures from adequately registering error and/or monitoring performance. Alternatively, the dACC, thalamus and insula show abnormally heightened responses to performance errors, suggesting that excessive responses to salient stimuli such as drug cues could precipitate craving. The two hypotheses would each predict decreased and increased activity during stop error (SE) as compared to stop success (SS) trials in the SST. Here we showed that cocaine dependent patients (PCD) experienced greater subjective feeling of loss of control and cocaine craving during early (average of day 6) compared to late (average of day 18) abstinence. Furthermore, compared to PCD during late abstinence, PCD scanned during early abstinence showed increased thalamic as well as insular but not dACC responses to errors (SE>SS). These findings support the hypothesis that heightened thalamic reactivity to salient stimuli co-occur with cocaine craving and loss of self control. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.
Morgan, V; Pickens, D; Gautam, S; Kessler, R; Mertz, H
2005-05-01
Irritable bowel syndrome (IBS) is a disorder of intestinal hypersensitivity and altered motility, exacerbated by stress. Functional magnetic resonance imaging (fMRI) during painful rectal distension in IBS has demonstrated greater activation of the anterior cingulate cortex (ACC), an area relevant to pain and emotions. Tricyclic antidepressants are effective for IBS. The aim of this study was to determine if low dose amitriptyline reduces ACC activation during painful rectal distension in IBS to confer clinical benefits. Secondary aims were to identify other brain regions altered by amitriptyline, and to determine if reductions in cerebral activation are greater during mental stress. Nineteen women with painful IBS were randomised to amitriptyline 50 mg or placebo for one month and then crossed over to the alternate treatment after washout. Cerebral activation during rectal distension was compared between placebo and amitriptyline groups by fMRI. Distensions were performed alternately during auditory stress and relaxing music. Rectal pain induced significant activation of the perigenual ACC, right insula, and right prefrontal cortex. Amitriptyline was associated with reduced pain related cerebral activations in the perigenual ACC and the left posterior parietal cortex, but only during stress. The tricyclic antidepressant amitriptyline reduces brain activation during pain in the perigenual (limbic) anterior cingulated cortex and parietal association cortex. These reductions are only seen during stress. Amitriptyline is likely to work in the central nervous system rather than peripherally to blunt pain and other symptoms exacerbated by stress in IBS.
Almeida Montes, Luis Guillermo; Prado Alcántara, Hugo; Portillo Cedeño, Bertha Alicia; Hernández García, Ana Olivia; Fuentes Rojas, Patricia Elisa
2015-06-01
Major depressive disorder (MDD) is recurrent, and its pathophysiology is not fully understood. Studies using electric tomography (ET) have identified abnormalities in the current density (CD) of MDD subjects in regions associated with the neurobiology of MDD, such as the anterior cingulate cortex (ACC) and medial orbitofrontal cortex (mOFC). However, little is known regarding the long-term CD changes in MDD subjects who respond to antidepressants. The aim of this study was to compare CD between healthy and MDD subjects who received 1-year open-label treatment with fluoxetine. Thirty-two-channel electroencephalograms (EEGs) were collected from 70 healthy controls and 74 MDD subjects at baseline (pre-treatment), 1 and 2weeks and 1, 2, 6, 9 and 12months. Variable-resolution ET (VARETA) was used to assess the CD between subject groups at each time point. The MDD group exhibited decreased alpha CD (αCD) in the occipital and parietal cortices, ACC, mOFC, thalamus and caudate nucleus at each time point. The αCD abnormalities persisted in the MDD subjects despite their achieving full remission. The low sub-alpha band was different between the healthy and MDD subjects. Differences in the amount of αCD between sexes and treatment outcomes were observed. Lack of a placebo arm and the loss of depressed patients to follow-up were significant limitations. The persistence of the decrease in αCD might suggest that the underlying pathophysiologic mechanisms of MDD are not corrected despite the asymptomatic state of MDD subjects, which could be significant in understanding the highly recurrent nature of MDD. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Jena, Babula
2016-09-01
The presence of the Kerguelen Plateau and surrounding bathymetric features has a strong influence on the persistently eastward flowing Antarctic Circumpolar Current (ACC), resulting in enhancement of surface chlorophyll-a (Chl- a) in the downstream section of the plateau along the polar front (PF). The phenomenon is reported in this paper as the island mass effect (IME). Analysis of climatological Chl- a datasets from Aqua- Moderate Resolution Imaging Spectroradiometer (Aqua- MODIS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows distinct bloomy plumes (Chl- a>0.5 mg/m3) during austral spring-summer spreading as far as ~1800 km offshore up to 98°E along the downstream of the north Kerguelen Plateau (NKP). Similar IME phenomena is apparent over the south Kerguelen Plateau (SKP) with the phytoplankton bloom extending up to 96.7°E, along the southern boundary of ACC. The IME phenomena are pronounced only during austral spring-summer period with the availability of light and sedimentary source of iron from shallow plateau to sea surface that fertilizes the mixed layer. The NKP bloom peaks with a maximum areal extent of 1.315 million km2 during December, and the SKP bloom peaks during January with a time lag of one month. The blooms exist for at least 4 months of a year and are significant both as the base of regional food web and for regulating the biogeochemical cycle in the Southern Ocean. Even though the surface water above the Kerguelen Plateau is rich in Chl- a, an exception of an oligotrophic condition dominated between NKP and SKP due to apparent intrusion of iron limited low phytoplankton regime waters from the Enderby basin through the northeastward Fawn Trough Current.
NASA Astrophysics Data System (ADS)
Li, Guilin; Zhang, Yanming; Ni, Yong; Wang, Ying; Xu, Baohua; Guo, Xingqi
2018-04-01
It is known that melatonin plays an indispensable role in the defense against some environment-induced stresses. The melatonin receptor (MTNR) is also closely linked to the environmental stress response in mammals. However, little is known about the function of the MTNR in insects, including honeybees. In this study, we identified a MTNR from Apis cerana cerana named AccMTNR1A, which contained a typical seven-transmembrane domain common to this family of receptors. A subcellular localization analysis showed that AccMTNR1A was localized in the cytomembrane. Additionally, we found that cold stress apparently boosted AccMTNR1A transcription, indicating that AccMTNR1A possibly connects to the cold stress response. The knockdown of AccMTNR1A attenuated the expression level of some genes associated with the cold stress response, suggesting that AccMTNR1A likely plays an analogous role with these genes during low temperature stress response. Moreover, silencing of AccMTNR1A also suppressed the transcription of some antioxidant genes, prompting the possibility that the response of AccMTNR1A to cold stress response may be related to antioxidant signaling pathways. Collectively, the findings presented here provide evidence that AccMTNR1A may play essential roles in protecting Apis cerana cerana from cold stress.
Steady-state kinetics of substrate binding and iron release in tomato ACC oxidase.
Thrower, J S; Blalock, R; Klinman, J P
2001-08-14
1-Aminocyclopropane-1-carboxylate oxidase (ACC oxidase) catalyzes the last step in the biosynthetic pathway of the plant hormone, ethylene. This unusual reaction results in the oxidative ring cleavage of 1-aminocyclopropane carboxylate (ACC) into ethylene, cyanide, and CO2 and requires ferrous ion, ascorbate, and molecular oxygen for catalysis. A new purification procedure and assay method have been developed for tomato ACC oxidase that result in greatly increased enzymatic activity. This method allowed us to determine the rate of iron release from the enzyme and the effect of the activator, CO2, on this rate. Initial velocity studies support an ordered kinetic mechanism where ACC binds first followed by O2; ascorbate can bind after O2 or possibly before ACC. This kinetic mechanism differs from one recently proposed for the ACC oxidase from avocado.
Multiple cognitive control mechanisms associated with the nature of conflict.
Kim, Chobok; Chung, Chongwook; Kim, Jeounghoon
2010-06-07
Cognitive control is required to regulate conflict. The conflict monitoring theory suggests that the dorsal anterior cingulate cortex (dACC) is involved in detecting response conflict and the dorsolateral prefrontal cortex (DLPFC) plays a critical role in regulating conflict. Recent studies, however, have suggested that rostral dACC (rdACC) responds to response conflict whereas caudal dACC (cdACC) is associated with perceptual conflict. Moreover, DLPFC has been engaged only in regulation of response conflict. A neural network involved in perceptual conflict, however, remains unclear. In this study, we used functional magnetic resonance imaging (fMRI) in an attempt to reveal monitor-controller networks corresponding to either perceptual conflict or response conflict. A version of the Stroop color matching task was used to manipulate perceptual conflict, response conflict was manipulated by an arrow. The results demonstrated that rdACC and DLPFC were engaged in response conflict whereas cdACC and the dorsal portion of premotor cortex (pre-PMd) were involved in perceptual conflict. Interestingly, the posterior parietal cortex (PPC) was activated by both types of conflict. Correlation analyses between behavioral conflict effects and neural responses demonstrated that rdACC and DLPFC were associated with response conflict whereas cdACC and pre-PMd were associated with perceptual conflict. PPC was not correlated with either perceptual conflict or response conflict. We suggest that cdACC and pre-PMd play critical roles in perceptual conflict processing, and this network is independent from the rdACC/DLPFC network for response conflict processing. We also discussed the function of PPC in conflict processing. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
Meyer, Meghan L.; Masten, Carrie L.; Ma, Yina; Wang, Chenbo; Shi, Zhenhao; Eisenberger, Naomi I.; Han, Shihui
2013-01-01
Humans observe various peoples’ social suffering throughout their lives, but it is unknown whether the same brain mechanisms respond to people we are close to and strangers’ social suffering. To address this question, we had participant’s complete functional magnetic resonance imaging (fMRI) while observing a friend and stranger experience social exclusion. Observing a friend’s exclusion activated affective pain regions associated with the direct (i.e. firsthand) experience of exclusion [dorsal anterior cingulate cortex (dACC) and insula], and this activation correlated with self-reported self-other overlap with the friend. Alternatively, observing a stranger’s exclusion activated regions associated with thinking about the traits, mental states and intentions of others [‘mentalizing’; dorsal medial prefrontal cortex (DMPFC), precuneus, and temporal pole]. Comparing activation from observing friend’s vs stranger’s exclusion showed increased activation in brain regions associated with the firsthand experience of exclusion (dACC and anterior insula) and with thinking about the self [medial prefrontal cortex (MPFC)]. Finally, functional connectivity analyses demonstrated that MPFC and affective pain regions activated in concert during empathy for friends, but not strangers. These results suggest empathy for friends’ social suffering relies on emotion sharing and self-processing mechanisms, whereas empathy for strangers’ social suffering may rely more heavily on mentalizing systems. PMID:22355182
Resting-state functional connectivity in combat veterans suffering from impulsive aggression
Heesink, Lieke; van Honk, Jack; Geuze, Elbert
2017-01-01
Abstract Impulsive aggression is common among military personnel after deployment and may arise because of impaired top-down regulation of the amygdala by prefrontal regions. This study sought to further explore this hypothesis via resting-state functional connectivity analyses in impulsively aggressive combat veterans. Male combat veterans with (n = 28) and without (n = 30) impulsive aggression problems underwent resting-state functional magnetic resonance imaging. Functional connectivity analyses were conducted with the following seed-regions: basolateral amygdala (BLA), centromedial amygdala, anterior cingulate cortex (ACC), and anterior insular cortex (AIC). Regions-of-interest analyses focused on the orbitofrontal cortex and periaqueductal gray, and yielded no significant results. In exploratory cluster analyses, we observed reduced functional connectivity between the (bilateral) BLA and left dorsolateral prefrontal cortex in the impulsive aggression group, relative to combat controls. This finding indicates that combat-related impulsive aggression may be marked by weakened functional connectivity between the amygdala and prefrontal regions, already in the absence of explicit emotional stimuli. Group differences in functional connectivity were also observed between the (bilateral) ACC and left cuneus, which may be related to heightened vigilance to potentially threatening visual cues, as well as between the left AIC and right temporal pole, possibly related to negative memory association in impulsive aggression. PMID:29040723
24 CFR 882.403 - ACC, housing assistance payments contract, and lease.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false ACC, housing assistance payments... Procedures for Moderate Rehabilitation-Basic Policies § 882.403 ACC, housing assistance payments contract, and lease. (a) Maximum Total ACC Commitments. The maximum total annual contribution that may be...
Code of Federal Regulations, 2011 CFR
2011-04-01
... give greater rights or funds to any party than are provided under the Agreement, Contract, and/or ACC..., Contract or ACC entered into pursuant to this part: Provided, however, That such financing is in connection..., Contract, or ACC, or payments thereunder, will be limited to the amounts payable under the Contract or ACC...
Code of Federal Regulations, 2011 CFR
2011-04-01
...(s) for which they assumed management responsibilities. (2) ACC. The ACC makes a PHA legally... the PHA and not the RMC or AME is ultimately responsible to HUD under the ACC, the PHAS score of a PHA will be based on all of the projects covered by the ACC, including those with management operations...
24 CFR 982.154 - ACC reserve account.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false ACC reserve account. 982.154... and PHA Administration of Program § 982.154 ACC reserve account. (a) HUD may establish and maintain an unfunded reserve account for the PHA program from available budget authority under the consolidated ACC...
24 CFR 982.154 - ACC reserve account.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false ACC reserve account. 982.154... and PHA Administration of Program § 982.154 ACC reserve account. (a) HUD may establish and maintain an unfunded reserve account for the PHA program from available budget authority under the consolidated ACC...
Kaliaperumal, Jagatheesh; Padarthi, Pavankumar; Elangovan, Namasivayam; Hari, Natarajan
2014-07-01
At present, the majority of established treatments for breast cancer are based on clinical manifestations, some fundamental of molecular and cellular biology of cancer. In recent times, the therapy is moving towards personalized medicines. Nevertheless, both the methodologies have own demerits. In the present study, we proposed a novel idea of targeted therapy with twin pharmacological potential by a peptide pACC1. The peptide was formulated with chitosan and evaluated with DMBA induced mammary carcinoma. Results suggest that the peptide holds great control on tumor cell multiplication, fatty acid synthesis and lactate levels. In addition, peptide also brings normal metabolic signs in glycolytic and glycogenic pathways. Histological studies confirm the dual pharmacological actions. Further, it is also proven that the peptide controls membrane receptor levels of HER2 and EGFR. In conclusion, that the peptide pACC1 could be employed as greater therapeutic adjuvant with currently established drugs without considering the stage of the cancer. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Strategic modulation of cognitive control.
Lungu, Ovidiu V; Liu, Tao; Waechter, Tobias; Willingham, Daniel T; Ashe, James
2007-08-01
The neural substrate of cognitive control is thought to comprise an evaluative component located in the anterior cingulate cortex (ACC) and an executive component in the prefrontal cortex (PFC). The control mechanism itself is mainly local, triggered by response conflict (monitored by the ACC) and involving the allocation of executive resources (recruited by the PFC) in a trial-to-trial fashion. However, another way to achieve control would be to use a strategic mechanism based on long-term prediction of upcoming events and on a chronic response strategy that ignores local features of the task. In the current study, we showed that such a strategic control mechanism was based on a functional dissociation or complementary relationship between the ACC and the PFC. When information in the environment was available to make predictions about upcoming stimuli, local task features (e.g., response conflict) were no longer used as a control signal. We suggest that having separate control mechanisms based on local or global task features allows humans to be persistent in pursuing their goals, yet flexible enough to adapt to changes in the environment.
Lu, Bo; Jiang, Jingyan; Sun, Jianliang; Xiao, Chun; Meng, Bo; Zheng, Jinwei; Li, Xiaoyu; Wang, Ruichun; Wu, Guorong; Chen, Junping
2016-09-01
Pain is a complex experience that comprises both sensory and affective dimensions. Mammalian target of rapamycin (mTOR) plays an important role in the modulation of neuronal plasticity associated with the pathogenesis of pain sensation. However, the role of mTOR in pain affect is unclear. Using a formalin-induced conditioned place avoidance (F-CPA) test, the current study investigated the effects of the mTOR specific inhibitor rapamycin on noxious stimulation induced aversion in the rostral anterior cingulate cortex (rACC). Intraplantar injection of 5% formalin was associated with significant activation of mTOR, as well as p70 ribosomal S6 protein (p70S6K), its downstream effector, in the rACC. The inhibition of mTOR activation with rapamycin disrupted pain-related aversion; however, this inhibition did not affect formalin-induced spontaneous nociceptive behaviors in rats. These findings demonstrated for the first time that mTOR and its downstream pathway in the rACC contribute to the induction of pain-related negative emotion. Copyright © 2016 Elsevier B.V. All rights reserved.
Submesoscale Rossby waves on the Antarctic circumpolar current
Bachman, Scott; Sallee, Jean-Baptiste
2018-01-01
The eastward-flowing Antarctic circumpolar current (ACC) plays a central role in the global ocean overturning circulation and facilitates the exchange of water between the ocean surface and interior. Submesoscale eddies and fronts with scales between 1 and 10 km are regularly observed in the upper ocean and are associated with strong vertical circulations and enhanced stratification. Despite their importance in other locations, comparatively little is known about submesoscales in the Southern Ocean. We present results from new observations, models, and theories showing that submesoscales are qualitatively changed by the strong jet associated with the ACC in the Scotia Sea, east of Drake Passage. Growing submesoscale disturbances develop along a dense filament and are transformed into submesoscale Rossby waves, which propagate upstream relative to the eastward jet. Unlike their counterparts in slower currents, the submesoscale Rossby waves do not destroy the underlying frontal structure. The development of submesoscale instabilities leads to strong net subduction of water associated with a dense outcropping filament, and later, the submesoscale Rossby waves are associated with intense vertical circulations. PMID:29670936
NASA Astrophysics Data System (ADS)
Tamsitt, V. M.; Talley, L. D.; Mazloff, M. R.
2014-12-01
The Southern Ocean displays a zonal dipole (wavenumber one) pattern in sea surface temperature (SST), with a cool zonal anomaly in the Atlantic and Indian sectors and a warm zonal anomaly in the Pacific sector, associated with the large northward excursion of the Malvinas and southeastward flow of the Antarctic Circumpolar Current (ACC). To the north of the cool Indian sector is the warm, narrow Agulhas Return Current (ARC). Air-sea heat flux is largely the inverse of this SST pattern, with ocean heat gain in the Atlantic/Indian, cooling in the southeastward-flowing ARC, and cooling in the Pacific, based on adjusted fluxes from the Southern Ocean State Estimate (SOSE), a ⅙° eddy permitting model constrained to all available in situ data. This heat flux pattern is dominated by turbulent heat loss from the ocean (latent and sensible), proportional to perturbations in the difference between SST and surface air temperature, which are maintained by ocean advection. Locally in the Indian sector, intense heat loss along the ARC is contrasted by ocean heat gain of 0.11 PW south of the ARC. The IPCC AR5 50 year depth-averaged 0-700 m temperature trend shows surprising similarities in its spatial pattern, with upper ocean warming in the ARC contrasted by cooling to the south. Using diagnosed heat budget terms from the most recent (June 2014) 6-year run of the SOSE we find that surface cooling in the ARC is balanced by heating from south-eastward advection by the current whereas heat gain in the ACC is balanced by cooling due to northward Ekman transport driven by strong westerly winds. These results suggest that spatial patterns in multi-decadal upper ocean temperature trends depend on regional variations in upper ocean dynamics.
Lattice QCD simulations using the OpenACC platform
NASA Astrophysics Data System (ADS)
Majumdar, Pushan
2016-10-01
In this article we will explore the OpenACC platform for programming Graphics Processing Units (GPUs). The OpenACC platform offers a directive based programming model for GPUs which avoids the detailed data flow control and memory management necessary in a CUDA programming environment. In the OpenACC model, programs can be written in high level languages with OpenMP like directives. We present some examples of QCD simulation codes using OpenACC and discuss their performance on the Fermi and Kepler GPUs.
Akdeniz, Ceren; Tost, Heike; Streit, Fabian; Haddad, Leila; Wüst, Stefan; Schäfer, Axel; Schneider, Michael; Rietschel, Marcella; Kirsch, Peter; Meyer-Lindenberg, Andreas
2014-06-01
Relative risk for the brain disorder schizophrenia is more than doubled in ethnic minorities, an effect that is evident across countries and linked to socially relevant cues such as skin color, making ethnic minority status a well-established social environmental risk factor. Pathoepidemiological models propose a role for chronic social stress and perceived discrimination for mental health risk in ethnic minorities, but the neurobiology is unexplored. To study neural social stress processing, using functional magnetic resonance imaging, and associations with perceived discrimination in ethnic minority individuals. Cross-sectional design in a university setting using 3 validated paradigms to challenge neural social stress processing and, to probe for specificity, emotional and cognitive brain functions. Healthy participants included those with German lineage (n = 40) and those of ethnic minority (n = 40) from different ethnic backgrounds matched for sociodemographic, psychological, and task performance characteristics. Control comparisons examined stress processing with matched ethnic background of investigators (23 Turkish vs 23 German participants) and basic emotional and cognitive tasks (24 Turkish vs 24 German participants). Blood oxygenation level-dependent response, functional connectivity, and psychological and physiological measures. There were significant increases in heart rate (P < .001), subjective emotional response (self-related emotions, P < .001; subjective anxiety, P = .006), and salivary cortisol level (P = .004) during functional magnetic resonance imaging stress induction. Ethnic minority individuals had significantly higher perceived chronic stress levels (P = .02) as well as increased activation (family-wise error-corrected [FWE] P = .005, region of interest corrected) and increased functional connectivity (PFWE = .01, region of interest corrected) of perigenual anterior cingulate cortex (ACC). The effects were specific to stress and not explained by a social distance effect. Ethnic minority individuals had significant correlations between perceived group discrimination and activation in perigenual ACC (PFWE = .001, region of interest corrected) and ventral striatum (PFWE = .02, whole brain corrected) and mediation of the relationship between perceived discrimination and perigenual ACC-dorsal ACC connectivity by chronic stress (P < .05). Epidemiologists proposed a causal role of social-evaluative stress, but the neural processes that could mediate this susceptibility effect were unknown. Our data demonstrate the potential of investigating associations from epidemiology with neuroimaging, suggest brain effects of social marginalization, and highlight a neural system in which environmental and genetic risk factors for mental illness may converge.
‘Imagined guilt’ vs ‘recollected guilt’: implications for fMRI
Mclatchie, Neil; Giner-Sorolla, Roger; Derbyshire, Stuart W. G.
2016-01-01
Abstract Guilt is thought to maintain social harmony by motivating reparation. This study compared two methodologies commonly used to identify the neural correlates of guilt. The first, imagined guilt, requires participants to read hypothetical scenarios and then imagine themselves as the protagonist. The second, recollected guilt, requires participants to reflect on times they personally experienced guilt. In the fMRI scanner, participants were presented with guilt/neutral memories and guilt/neutral hypothetical scenarios. Contrasts confirmed a priori predictions that guilt memories, relative to guilt scenarios, were associated with significantly greater activity in regions associated with affect [anterior cingulate cortex (ACC), Caudate, Insula, orbital frontal cortex (OFC)] and social cognition [temporal pole (TP), precuneus). Similarly, results indicated that guilt memories, relative to neutral memories, were also associated with greater activity in affective (ACC, amygdala, Insula, OFC) and social cognition (mPFC, TP, precuneus, temporo-parietal junction) regions. There were no significant differences between guilt hypothetical scenarios and neutral hypothetical scenarios in either affective or social cognition regions. The importance of distinguishing between different guilt inductions inside the scanner is discussed. We offer explanations of our results and discuss ideas for future research. PMID:26746179
Is there a core neural network in empathy? An fMRI based quantitative meta-analysis.
Fan, Yan; Duncan, Niall W; de Greck, Moritz; Northoff, Georg
2011-01-01
Whilst recent neuroimaging studies have identified a series of different brain regions as being involved in empathy, it remains unclear concerning the activation consistence of these brain regions and their specific functional roles. Using MKDA, a whole-brain based quantitative meta-analysis of recent fMRI studies of empathy was performed. This analysis identified the dACC-aMCC-SMA and bilateral anterior insula as being consistently activated in empathy. Hypothesizing that what are here termed affective-perceptual and cognitive-evaluative forms of empathy might be characterized by different activity patterns, the neural activations in these forms of empathy were compared. The dorsal aMCC was demonstrated to be recruited more frequently in the cognitive-evaluative form of empathy, whilst the right anterior insula was found to be involved in the affective-perceptual form of empathy only. The left anterior insula was active in both forms of empathy. It was concluded that the dACC-aMCC-SMA and bilateral insula can be considered as forming a core network in empathy, and that cognitive-evaluative and affective-perceptual empathy can be distinguished at the level of regional activation. Copyright © 2010 Elsevier Ltd. All rights reserved.
'Imagined guilt' vs 'recollected guilt': implications for fMRI.
Mclatchie, Neil; Giner-Sorolla, Roger; Derbyshire, Stuart W G
2016-05-01
Guilt is thought to maintain social harmony by motivating reparation. This study compared two methodologies commonly used to identify the neural correlates of guilt. The first, imagined guilt, requires participants to read hypothetical scenarios and then imagine themselves as the protagonist. The second, recollected guilt, requires participants to reflect on times they personally experienced guilt. In the fMRI scanner, participants were presented with guilt/neutral memories and guilt/neutral hypothetical scenarios. Contrasts confirmed a priori predictions that guilt memories, relative to guilt scenarios, were associated with significantly greater activity in regions associated with affect [anterior cingulate cortex (ACC), Caudate, Insula, orbital frontal cortex (OFC)] and social cognition [temporal pole (TP), precuneus). Similarly, results indicated that guilt memories, relative to neutral memories, were also associated with greater activity in affective (ACC, amygdala, Insula, OFC) and social cognition (mPFC, TP, precuneus, temporo-parietal junction) regions. There were no significant differences between guilt hypothetical scenarios and neutral hypothetical scenarios in either affective or social cognition regions. The importance of distinguishing between different guilt inductions inside the scanner is discussed. We offer explanations of our results and discuss ideas for future research. © The Author (2016). Published by Oxford University Press.
Takeuchi, Hikaru; Taki, Yasuyuki; Sassa, Yuko; Hashizume, Hiroshi; Sekiguchi, Atsushi; Nagase, Tomomi; Nouchi, Rui; Fukushima, Ai; Kawashima, Ryuta
2012-02-01
During Stroop tasks, subjects experience cognitive interference when they resolve interferences such as identifying the ink color of a printed word while ignoring the word's identity. Stroop paradigms are commonly used as an index of attention deficits and a tool for investigating the functions of the frontal lobes and other associated structures. Despite these uses and the vast amount of attention given to Stroop paradigms, the regional gray matter volume/regional white matter volume (rGMV/rWMV) correlates of Stroop interference have not yet been identified at the whole brain level in normal adults. We examined this issue using voxel-based morphometry in right-handed healthy young adults. We found significant negative relationships between the Stroop interference rate and rGMV in the anterior cingulate cortex (ACC), right inferior frontal gyrus, and cerebellum. Furthermore, we found relationships between the Stroop interference rate and rWMV in bilateral anatomical clusters that extended around extensive WM regions in the dorsal part of the frontal lobe. These findings are the first to reveal rGMV/rWMV that underlie the performance of the Stroop task, a widely used psychological paradigm at the whole brain level. Of note, our findings support the notion that ACC contributes to Stroop performance and show the involvement of regions that have been implicated in response inhibition and attention. Copyright © 2011 Elsevier Inc. All rights reserved.
The ACC strategy in biomineralization: the case of earthworm's amorphous spherulites
NASA Astrophysics Data System (ADS)
Briones, Maria J. I.; Alvarez-Otero, Rosa; Méndez, Jesús; Gago Duport, Luis
2010-05-01
The occurrence of amorphous calcium carbonate (ACC), an hydrated and highly soluble form of solid CaCO3, seems to be a common feature in all carbonate forming organisms such as mollusks, corals, echinoderms and crustaceans. The ubiquity of ACC in these Ca-carbonate biomineralizing systems, as a precursor of further crystalline phases, has recently open the interesting question about if the formation of an amorphous phase is a necessary step in the calcification process of all organisms and consequently, whether it would be possible to define the "amorphous precursor estategy" as a general mechanism in biomineralization. Neverthelees, although ACC appears to be widespread in these organisms very little is known about its particular role in the biomineralization scheme of the different phyla. The formation of CaCO3 spherulites in the calciferous glands of earthworms is a particular case of calcareous biomineralization involving the presence of ACC as a transient precursor phase [2]. Interestingly, the formation of crystalline carbonates via ACC in these organisms is not connected with skeleton building so it must play another functional role. In addition, the transient transformation stages can be followed by in situ spectrometric techniques and therefore, earthworms provide and adequate model to analyse the mutual interactions between ACC-solvent-and crystalline phases. In this study, we have analysed the morphological and structural transformations from the initial ACC spherulites until the formation of the crystalline phases: vaterite (and/or aragonite) and finally calcite, is accomplished. The characterization of ACC was done by performing in situ FT-IR, together with and HREM and Debye scherrer -XRD. The structural results were interpreted in the light of the histological study of the gland. The geometry of the secretory epithelium of the calciferous gland, as evidenced by TEM [2], shows the presence of irregulary shaped cells with their apical surface consisting of dendritic indentations and club-shaped expansions extending to the inter-lamella spaces. The cell basal area is extremely folded and contains abundant mitochondria and membranous infoldings. This morphology could provide the explanatory mechanism by which the calcium present in the blood enters into the gland. Furthermore, the presence of spherulites in the interlamellar space and wrapped by an organic matrix suggest that the calcification process is under organic control. Further information of the intermediate transformation stages in the ACC spherultiths was provided by the FE-SEM analysis. That shown the collapse of the internal structure of spherulits into radially distributed regions associated with the organic matrix. As ACC is a highly soluble form of CaCO3 that includes a water molecule in the structure, its transformation to one of the crystalline polymorphs, would necessarily involve the release of H2O and the Ca+2 ion. As a result of this, a gradual decrease in volume at the inner part of the spherulites is observed. Taken these findings together, we conclude that the transformation of the initially stabilised ACC occurs via a ‘source-sink mechanism'. Accordingly, the uptake of Ca by the cells (sink) causes a decrease in the [Ca+2] of the extracellular fluid. This, in turn, will induce the dissolution of the spherulites (source), with the subsequent release of H2O and Ca+2 so that the Ca activity in the extracellular fluid is maintained. As result of this process, while the concentrations of ACC become unsaturated, both vaterite and calcite are still supersaturated and crystallization can be then initiated via an heterogeneous nucleation mechanism at the spherulite surfaces. This mechanism can be used by the orgnism as an efficient way to control the concentration of Ca+2 in the extracellular fluid within its physiological range. References [1] Gago-Duport, L., Briones, M.J.I., Rodriguez, J.B., Covelo, B. (2008) J. Struct Biol, 162: 422-35. [2] Mendez J., Rodriguez, J.B., Alvarez-Otero, R., Briones M.J.I., Gago-Duport, L. Microsc Microanal 15 (supp 3): 25-26 (2009) DOI 10.1017/S1431927609990584
24 CFR 883.607 - Default by owner and/or agency.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Agency defaults under Agreement or Contract. The ACC, the Agreement and the Contract will provide that... enter into the Contract. (b) Rights of HUD if Agency defaults under ACC. The ACC will provide that, if...; however, HUD will continue to pay annual contributions in accordance with the terms of the ACC and the...
24 CFR 969.104 - Continuing eligibility for operating subsidy.
Code of Federal Regulations, 2010 CFR
2010-04-01
... in accordance with an ACC amendment providing for extension of the term of the ACC provisions related to project operation, pursuant to § 969.105 or § 969.106. The ACC amendment shall be in the form prescribed by HUD and shall specify the particular provisions of the ACC which relate to continued project...
Code of Federal Regulations, 2011 CFR
2011-04-01
....103 Definitions. (a) “ACC expiration date” means the last day of the term during which a particular public housing project is subject to all or any of the provisions of the ACC. The ACC term for a... Contribution Date for the project, as determined under the ACC (e.g., if the last debt service Annual...
24 CFR 882.805 - HA application process, ACC execution, and pre-rehabilitation activities.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false HA application process, ACC... § 882.805 HA application process, ACC execution, and pre-rehabilitation activities. (a) Review. When... applications in accordance with the guidelines, rating criteria, and procedures published in the NOFA. (b) ACC...
Code of Federal Regulations, 2010 CFR
2010-04-01
....103 Definitions. (a) “ACC expiration date” means the last day of the term during which a particular public housing project is subject to all or any of the provisions of the ACC. The ACC term for a... Contribution Date for the project, as determined under the ACC (e.g., if the last debt service Annual...
24 CFR 883.607 - Default by owner and/or agency.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Agency defaults under Agreement or Contract. The ACC, the Agreement and the Contract will provide that... enter into the Contract. (b) Rights of HUD if Agency defaults under ACC. The ACC will provide that, if...; however, HUD will continue to pay annual contributions in accordance with the terms of the ACC and the...
24 CFR 969.104 - Continuing eligibility for operating subsidy.
Code of Federal Regulations, 2011 CFR
2011-04-01
... in accordance with an ACC amendment providing for extension of the term of the ACC provisions related to project operation, pursuant to § 969.105 or § 969.106. The ACC amendment shall be in the form prescribed by HUD and shall specify the particular provisions of the ACC which relate to continued project...
Histopathology of acute acalculous cholecystitis in critically ill patients.
Laurila, J J; Ala-Kokko, T I; Laurila, P A; Saarnio, J; Koivukangas, V; Syrjälä, H; Karttunen, T J
2005-11-01
To illustrate the histopathological features of acute acalculous cholecystitis (AAC) of critically ill patients and to compare them with those of acute calculous cholecystitis (ACC) and normal gallbladders. We studied 34 gallbladders with AAC and compared them with 28 cases of ACC and 14 normal gallbladders. Histological features were systematically evaluated. Typical features in AAC were bile infiltration, leucocyte margination of blood vessels and lymphatic dilation. Bile infiltration in the gallbladder wall was more common and extended wider and deeper into the muscle layer in AAC compared with ACC. Epithelial degeneration and defects and widespread occurrence of inflammatory cells were typical features in ACC. Necrosis in the muscle layer was also more common and extended wider and deeper in ACC. There were no differences in the occurrence of capillary thromboses, lymphatic follicles or Rokitansky-Aschoff sinuses between the AAC and ACC samples. There are characteristic differences in histopathology between AAC and ACC, although due to overlap, none appeared to be specific as such for either condition. These results suggest that AAC is largely a manifestation of systemic critical illness, whereas ACC is a local disease of the gallbladder.
OpenARC: Extensible OpenACC Compiler Framework for Directive-Based Accelerator Programming Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Seyong; Vetter, Jeffrey S
2014-01-01
Directive-based, accelerator programming models such as OpenACC have arisen as an alternative solution to program emerging Scalable Heterogeneous Computing (SHC) platforms. However, the increased complexity in the SHC systems incurs several challenges in terms of portability and productivity. This paper presents an open-sourced OpenACC compiler, called OpenARC, which serves as an extensible research framework to address those issues in the directive-based accelerator programming. This paper explains important design strategies and key compiler transformation techniques needed to implement the reference OpenACC compiler. Moreover, this paper demonstrates the efficacy of OpenARC as a research framework for directive-based programming study, by proposing andmore » implementing OpenACC extensions in the OpenARC framework to 1) support hybrid programming of the unified memory and separate memory and 2) exploit architecture-specific features in an abstract manner. Porting thirteen standard OpenACC programs and three extended OpenACC programs to CUDA GPUs shows that OpenARC performs similarly to a commercial OpenACC compiler, while it serves as a high-level research framework.« less
NASA Astrophysics Data System (ADS)
Mackensen, A.; Zahn, R.; Hall, I.; Kuhn, G.; Koc, N.; Francois, R.; Hemming, S.; Goldstein, S.; Rogers, J.; Ehrmann, W.
2003-04-01
Quantifying oceanic variability at timescales of oceanic, atmospheric, and cryospheric processes are the fundamental objectives of the international IMAGES program. In this context the Southern Ocean plays a leading role in that it is involved, through its influence on global ocean circulation and carbon budget, with the development and maintenance of the Earth's climate system. The seas surrounding Antarctica contain the world's only zonal circum-global current system that entrains water masses from the three main ocean basins, and maintains the thermal isolation of Antarctica from warmer surface waters to the north. Furthermore, the Southern Ocean is a major site of bottom and intermediate water formation and thus actively impacts the global thermohaline circulation (THC). This proposal is an outcome of the IMAGES Southern Ocean Working Group and constitutes one component of a suite of new IMAGES/IODP initiatives that aim at resolving past variability of the Antarctic Circumpolar Current (ACC) on orbital and sub-orbital timescales and its involvement with rapid global ocean variability and climate instability. The primary aim of this proposal is to determine millennial- to sub-centennial scale variability of the ACC and the ensuing Atlantic-Indian water transports, including surface transports and deep-water flow. We will focus on periods of rapid ocean and climate change and assess the role of the Southern Ocean in these changes, both in terms of its thermohaline circulation and biogeochemical inventories. We propose a suite of 11 sites that form a latitudinal transect across the ACC in the westernmost Indian Ocean sector of the Southern Ocean. The transect is designed to allow the reconstruction of ACC variability across a range of latitudes in conjunction with meridional shifts of the surface ocean fronts. The northernmost reaches of the transect extend into the Agulhas Current and its retroflection system which is a key component of the THC warm water return flow to the Atlantic. The principal topics are: (i) the response of the ACC to climate variability; (ii) the history of the Southern Ocean surface ocean fronts during periods of rapid climate change; (iii) the history of North Atlantic Deep Water (NADW) export to the deep South Indian Ocean; (iv) the variability of Southern Ocean biogeochemical fluxes and their influence on Circumpolar Deep Water (CDW) carbon inventories and atmospheric chemistry; and (v) the variability of surface ocean fronts and the Indian-Atlantic surface ocean density flux. To achieve these objectives we will generate fine-scale records of palaeoceanographic proxies that are linked to a variety of climatically relevant ocean parameters. Temporal resolution of the records, depending on sedimentation rates, will range from millennial to sub-centennial time scales. Highest sedimentation rates are expected at coring sites located on current-controlled sediment drifts, whereas dense sampling of cores with moderate sedimentation rates will enable at least millennial-scale events to be resolved.
Luo, Jingtao; Hong, Yun; Lu, Yang; Qiu, Songbo; Chaganty, Bharat K. R.; Zhang, Lun; Wang, Xudong; Li, Qiang; Fan, Zhen
2016-01-01
Cetuximab inhibits HIF-1-regulated glycolysis in cancer cells, thereby reversing the Warburg effect and leading to inhibition of cancer cell metabolism. AMP-activated protein kinase (AMPK) is activated after cetuximab treatment, and a sustained AMPK activity is a mechanism contributing to cetuximab resistance. Here, we investigated how acetyl-CoA carboxylase (ACC), a downstream target of AMPK, rewires cancer metabolism in response to cetuximab treatment. We found that introduction of experimental ACC mutants lacking the AMPK phosphorylation sites (ACC1_S79A and ACC2_S212A) into head and neck squamous cell carcinoma (HNSCC) cells protected HNSCC cells from cetuximab-induced growth inhibition. HNSCC cells with acquired cetuximab resistance contained not only high levels of T172-phosphorylated AMPK and S79-phosphorylated ACC1 but also an increased level of total ACC. These findings were corroborated in tumor specimens of HNSCC patients treated with cetuximab. Cetuximab plus TOFA (an allosteric inhibitor of ACC) achieved remarkable growth inhibition of cetuximab-resistant HNSCC xenografts. Our data suggest a novel paradigm in which cetuximab-mediated activation of AMPK and subsequent phosphorylation and inhibition of ACC is followed by a compensatory increase in total ACC, which rewires cancer metabolism from glycolysis-dependent to lipogenesis-dependent. PMID:27693630
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hahn, H.A.; Ashworth, R.L. Jr.; Phelps, R.H.
1990-01-01
Asynchronous computer conferencing (ACC) was investigated as an alternative to resident training for the Army Reserve Component (RC). Specifically, the goals were to (1) evaluate the performance and throughput of ACC as compared with traditional Resident School instruction and (2) determine the cost-effectiveness of developing and implementing ACC. Fourteen RC students took a module of the Army Engineer Officer Advanced Course (EOAC) via ACC. Course topics included Army doctrine, technical engineering subjects, leadership, and presentation skills. Resident content was adapted for presentation via ACC. The programs of instruction for ACC and the equivalent resident course were identical; only the mediamore » used for presentation were changed. Performance on tests, homework, and practical exercises; self-assessments of learning; throughput; and cost data wee the measures of interest. Comparison data were collected on RC students taking the course in residence. Results indicated that there were no performance differences between the two groups. Students taking the course via ACC perceived greater learning benefit than did students taking the course in residence. Resident throughput was superior to ACC throughput, both in terms of numbers of students completing and time to complete the course. In spite of this fact, however, ACC was more cost-effective than resident training.« less
Phase transitions in biogenic amorphous calcium carbonate
NASA Astrophysics Data System (ADS)
Gong, Yutao
Geological calcium carbonate exists in both crystalline phases and amorphous phases. Compared with crystalline calcium carbonate, such as calcite, aragonite and vaterite, the amorphous calcium carbonate (ACC) is unstable. Unlike geological calcium carbonate crystals, crystalline sea urchin spicules (99.9 wt % calcium carbonate and 0.1 wt % proteins) do not present facets. To explain this property, crystal formation via amorphous precursors was proposed in theory. And previous research reported experimental evidence of ACC on the surface of forming sea urchin spicules. By using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), we studied cross-sections of fresh sea urchin spicules at different stages (36h, 48h and 72h after fertilization) and observed the transition sequence of three mineral phases: hydrated ACC → dehydrated ACC → biogenic calcite. In addition, we unexpectedly found hydrated ACC nanoparticles that are surrounded by biogenic calcite. This observation indicates the dehydration from hydrated ACC to dehydrated ACC is inhibited, resulting in stabilization of hydrated ACC nanoparticles. We thought that the dehydration was inhibited by protein matrix components occluded within the biomineral, and we designed an in vitro assay to test the hypothesis. By utilizing XANES-PEEM, we found that SM50, the most abundant occluded matrix protein in sea urchin spicules, has the function to stabilize hydrated ACC in vitro.
Error-Related Electrocortical Responses in 10-Year-Old Children and Young Adults
ERIC Educational Resources Information Center
Santesso, Diane L.; Segalowitz, Sidney J.; Schmidt, Louis A.
2006-01-01
Recent anatomical and electrophysiological evidence suggests that the anterior cingulate cortex (ACC) is relatively late to mature. This brain region appears to be critical for monitoring, evaluating, and adjusting ongoing behaviors. This monitoring elicits characteristic ERP components including the error-related negativity (ERN), error…
Valderrama, J. Andrés; Shingler, Victoria; Carmona, Manuel; Díaz, Eduardo
2014-01-01
Here we characterized the first known transcriptional regulator that accounts for carbon catabolite repression (CCR) control of the anaerobic catabolism of aromatic compounds in bacteria. The AccR response regulator of Azoarcus sp. CIB controls succinate-responsive CCR of the central pathways for the anaerobic catabolism of aromatics by this strain. Phosphorylation of AccR to AccR-P triggers a monomer-to-dimer transition as well as the ability to bind to the target promoter and causes repression both in vivo and in vitro. Substitution of the Asp60 phosphorylation target residue of the N-terminal receiver motif of AccR to a phosphomimic Glu residue generates a constitutively active derivative that behaves as a superrepressor of the target genes. AccR-P binds in vitro to a conserved inverted repeat (ATGCA-N6-TGCAT) present at two different locations within the PN promoter of the bzd genes for anaerobic benzoate degradation. Because the DNA binding-proficient C-terminal domain of AccR is monomeric, we propose an activation mechanism in which phosphorylation of Asp60 of AccR alleviates interdomain repression mediated by the N-terminal domain. The presence of AccR-like proteins encoded in the genomes of other β-proteobacteria of the Azoarcus/Thauera group further suggests that AccR constitutes a master regulator that controls anaerobic CCR in these bacteria. PMID:24302740
Mahabadi, Amir A; Möhlenkamp, Stefan; Lehmann, Nils; Kälsch, Hagen; Dykun, Iryna; Pundt, Noreen; Moebus, Susanne; Jöckel, Karl-Heinz; Erbel, Raimund
2017-02-01
The aim of this study was to assess the difference in indication for statin therapy by European Society of Cardiology (ESC) versus American Heart Association/American College of Cardiology (AHA/ACC) guidelines and to quantify the potential additional role of coronary artery calcification (CAC) score over updated guidelines in a primary prevention cohort. Recently, ESC and AHA/ACC updated the guidelines regarding statin therapy in primary prevention. In 3,745 subjects (59 ± 8 years of age, 47% men) from the population based longitudinal Heinz Nixdorf Recall cohort study without cardiovascular disease or lipid-lowering therapy at baseline CAC score was assessed between 2000 and 2003. Subjects remained unaware of their initial CAC score. Statin indication was determined according to 2012 ESC and 2013 AHA/ACC guidelines based on subjects individual baseline characteristics. The frequency of statin recommendation was lower according to ESC compared to AHA/ACC guidelines (34% vs. 56%; p < 0.0001), whereas low CAC score (<100) was common in subjects with statin indication by both guidelines (59% for ESC, 62% for AHA/ACC). During 10.4 ± 2.0 years of follow-up, 131 myocardial infarctions occurred. For ESC recommendations, CAC score differentiated risk for subjects without (1.0 [95% confidence interval (CI): 0.4 to 1.5] vs. 6.5 [95% CI: 4.1 to 8.9] coronary events per 1,000 person-years for CAC 0 vs. ≥100) and with statin indication (2.6 [95% CI: 0.6 to 4.7] vs. 9.9 [95% CI: 7.3 to 12.5] per 1,000 person-years for CAC 0 vs. ≥100). Likewise, CAC score stratified proportions experiencing events subjects with statin indication according to AHA/ACC (2.7 [95% CI: 1.1 to 4.2] vs. 9.1 [95% CI: 7.0 to 11.0] per 1,000 person-years for CAC 0 vs. ≥100), whereas event rate in subjects without statin indication was low (1.1 [95% CI: 0.65 to 1.68] per 1,000 person-years). Current ESC and AHA/ACC guidelines lead to markedly different recommendation regarding statin therapy in a German primary prevention cohort. Quantification of CAC score in addition to the guidelines improves stratification between subjects at high versus low risk for coronary events, indicating that CAC scoring may help to match intensified risk factor modification to atherosclerotic plaque burden as well as actual risk while avoiding therapy in subjects with low coronary atherosclerosis that have low 10-year event rate. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Minimal impact of age and housing temperature on the metabolic phenotype of Acc2-/- mice.
Brandon, Amanda E; Stuart, Ella; Leslie, Simon J; Hoehn, Kyle L; James, David E; Kraegen, Edward W; Turner, Nigel; Cooney, Gregory J
2016-03-01
An important regulator of fatty acid oxidation (FAO) is the allosteric inhibition of CPT-1 by malonyl-CoA produced by the enzyme acetyl-CoA carboxylase 2 (ACC2). Initial studies suggested that deletion of Acc2 (Acacb) increased fat oxidation and reduced adipose tissue mass but in an independently generated strain of Acc2 knockout mice we observed increased whole-body and skeletal muscle FAO and a compensatory increase in muscle glycogen stores without changes in glucose tolerance, energy expenditure or fat mass in young mice (12-16 weeks). The aim of the present study was to determine whether there was any effect of age or housing at thermoneutrality (29 °C; which reduces total energy expenditure) on the phenotype of Acc2 knockout mice. At 42-54 weeks of age, male WT and Acc2(-/-) mice had similar body weight, fat mass, muscle triglyceride content and glucose tolerance. Consistent with younger Acc2(-/-) mice, aged Acc2(-/-) mice showed increased whole-body FAO (24 h average respiratory exchange ratio=0.95±0.02 and 0.92±0.02 for WT and Acc2(-/-) mice respectively, P<0.05) and skeletal muscle glycogen content (+60%, P<0.05) without any detectable change in whole-body energy expenditure. Hyperinsulinaemic-euglycaemic clamp studies revealed no difference in insulin action between groups with similar glucose infusion rates and tissue glucose uptake. Housing Acc2(-/-) mice at 29 °C did not alter body composition, glucose tolerance or the effects of fat feeding compared with WT mice. These results confirm that manipulation of Acc2 may alter FAO in mice, but this has little impact on body composition or insulin action. © 2016 Society for Endocrinology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brewer, M; Gordon, C; Tien, C
Purpose: To follow the Integrating Healthcare Enterprise - Radiation Oncology (IHE-RO) initiative of proper cross-vendor technology integration, an automated chart checker (ACC) was developed. ACC compares extracted data from an approved patient plan in the Eclipse treatment planning system (TPS) against data existing in the Mosaiq treatment management system (TMS). ACC automatically analyzes these parameters using built-in quality checklists to provide further aid in chart review. Methods: Eclipse TPS data are obtained using Eclipse scripting API (ESAPI) while Mosaiq TMS data are obtained from a radiotherapy-treatment-planning (RTP) file. Using this information, ACC identifies TPS-TMS discrepancies in 18 primary beam parametersmore » including MU, energy, jaw positions, gantry angle, table angle, accessories, and bolus for up to 31 beams. Next, approximately 40 items from traditional quality checklists are evaluated such as prescription consistency, DRR graticule placement, plan approval status, global max dose, and dose tracking coefficients. Parameters were artificially modified to determine if ACC would detect an error in data transfer and to test each component of quality checklists. Results: Using ESAPI scripting and RTP file-processing, ACC was able to properly aggregate data from TPS and TMS for up to 31 beams. Errors were artificially introduced into each plan parameter, and ACC was able to successfully detect all of them within seconds. Next, ACC was able to successfully detect mistakes in the chart by identifying deviations with its quality checklists, within seconds. Conclusion: ACC effectively addresses the potential issue of faulty cross-vendor data transfer, as described by IHE-RO. In addition, ACC was also able to detect deviations from its built-in quality checklists. ACC is already an invaluable tool for efficient and standardized chart review and will continue to improve as its incorporated checklists become more comprehensive.« less
Schwarz, Stephan; Müller, Maximilian; Ettl, Tobias; Stockmann, Philipp; Zenk, Johannes; Agaimy, Abbas
2011-01-01
We analyzed 41 oral salivary gland carcinomas from consecutive 290 salivary gland carcinoma database (14%) with emphasis on the histological spectrum and clinical outcome of adenoid cystic carcinoma (ACC) and polymorphous low-grade adenocarcinoma (PLGA). The cohort included 14 ACCs, 14 mucoepidermoid carcinomas (MECs), 8 PLGAs, 3 adenocarcinomas, not otherwise specified and 2 acinic cell carcinomas. Mean age was 48, 58 and 61 yrs for ACC, MEC and PLGA, respectively. Eight patients (19.5%) died of tumor at a mean interval of 66.5 months. ACC and PLGA showed similar mean age, gender distribution, predominant palatal localization, nodal metastasis, perineural invasion and MIB-1 index. However, ACC tended to show higher tumor stage and residual tumor (R1/R2) more frequently than PLGA, but this was statistically not significant. ACC and PLGA showed overlapping architectural patterns. However, ACCs displayed well organized basal-luminal differentiation, highlighted by CK5/CK7 immunostaining. In contrast, PLGA showed a disorganized histological and immunohistological pattern. C-Kit expression (CD117) was common in ACC, generally mirroring that of CK7 and virtually lacking in PLGA. Kaplan-Meier analysis demonstrated a similar clinical course for ACC and PLGA with 5 years survivals of 87% and 80%, respectively. Fluorescence in situ hybridization (FISH) performed on all 290 salivary carcinomas confirmed the specificity of the translocation t (11; 19) for MEC and its absence in all other carcinomas including ACC and PLGA. Our results emphasize the diversity of oral salivary gland carcinomas and the overlapping clinicopathological features of ACC and PLGA. PMID:21577319
NASA Astrophysics Data System (ADS)
Mergelsberg, S. T.; Ulrich, R. N.; Michel, F. M.; Dove, P. M.
2016-12-01
Calcium carbonate minerals are an essential component in the exoskeletons of crustaceans and mollusks. The onset of exoskeleton mineralization includes the precipitation of amorphous calcium carbonate (ACC) as a reactive intermediate that later transforms to produce diverse structures. Despite the importance of ACC as a critical phase during skeleton formation, the chemical and physical properties are not well characterized at conditions that approximate biological environments. Of particular interest are the solubility of ACC, the short-range structure at the time of formation, and the evolution of ACC structure to final products. Recent advances showing the widespread occurrence of multistep pathways to mineralization in biological and geological settings (De Yoreo et al., 2015) underline the importance of understanding amorphous intermediates. Using quantitative laboratory techniques developed by our research group (Blue et al., 2013; Blue and Dove, 2015; Blue et al., in press), this experimental study quantifies the solubility of ACC in parallel with the physical characterization of the corresponding structure. We measured ACC solubility at specific time points during the precipitation and during its subsequent evolution under the mild pH conditions that approximate biological and environmental conditions. In parallel experiments, structural data were collected from in situ pair distribution function (PDF) analyses were conducted to follow the evolution of individual samples from initial precipitation to final product. The measurements are leading to a quantitative solubility function for ACC with variable Mg contents and an x-ray based understanding of ACC structure in the same particles. We are also finding temporal changes in the short-range order of ACC after precipitation and this order is dependent upon Mg content. Moreover, the data show Mg distribution through the ACC particles is dependent upon total alkalinity. Insights from this study hold promise for better understanding the nature of the initial ACC that forms and factors that influence its structural evolution to final products.
Coordinated Interaction between Hippocampal Sharp-Wave Ripples and Anterior Cingulate Unit Activity
2016-01-01
Hippocampal–cortical interaction during sleep promotes transformation of memory for long-term storage in the cortex. In particular, hippocampal sharp-wave ripple-associated neural activation is important for this transformation during slow-wave sleep. The anterior cingulate cortex (ACC) has been shown to be crucial for expression and likely storage of long-term memory. However, little is known about how ACC activity is influenced by hippocampal ripple activity during sleep. We report here about coordinated interactions between hippocampal ripple activity and ACC neural firings. By recording from the ACC and hippocampal CA1 simultaneously in mice, we found that almost all ACC neurons showed increased activity before hippocampal ripple activity; moreover, a subpopulation (17%) displayed a further activation immediately after ripple activity. This postripple activation of ACC neurons correlated positively with ripple amplitude, and the same neurons were excited upon electrical stimulation of the CA1. Interestingly, the preripple activation of ACC neurons was present during the sleep state, but not during the awake state. These results suggest intimate interactions between hippocampal sharp-wave ripples and ACC neurons in a state-dependent manner. Importantly, sharp-wave ripples and associated activation appear to regulate activity of a small population of ACC neurons, a process that may play a critical role in memory consolidation. SIGNIFICANCE STATEMENT The hippocampus communicates with the cortex for memory transformation. Memories of previous experiences become less dependent on the hippocampus and increasingly dependent on cortical areas, such as the anterior cingulate cortex (ACC). However, little evidence is available to directly support this hippocampus-to-cortex information transduction hypothesis of memory consolidation. Here we show that a subpopulation of ACC neurons becomes active just after hippocampal ripple activity, and that electrical stimulation of the hippocampus excites the same ACC neurons. In addition, the majority of ACC neurons are activated just before ripple activity during the sleep state, but not during the awake state. These results provide evidence supporting the hypothesis of hippocampus-to-cortex information flow for memory consolidation as well as reciprocal interaction between the hippocampus and the cortex. PMID:27733616
Vavvas, D; Apazidis, A; Saha, A K; Gamble, J; Patel, A; Kemp, B E; Witters, L A; Ruderman, N B
1997-05-16
The concentration of malonyl-CoA, a negative regulator of fatty acid oxidation, diminishes acutely in contracting skeletal muscle. To determine how this occurs, the activity and properties of acetyl-CoA carboxylase beta (ACC-beta), the skeletal muscle isozyme that catalyzes malonyl-CoA formation, were examined in rat gastrocnemius-soleus muscles at rest and during contractions induced by electrical stimulation of the sciatic nerve. To avoid the problem of contamination of the muscle extract by mitochondrial carboxylases, an assay was developed in which ACC-beta was first purified by immunoprecipitation with a monoclonal antibody. ACC-beta was quantitatively recovered in the immunopellet and exhibited a high sensitivity to citrate (12-fold activation) and a Km for acetyl-CoA (120 microM) similar to that reported for ACC-beta purified by other means. After 5 min of contraction, ACC-beta activity was decreased by 90% despite an apparent increase in the cytosolic concentration of citrate, a positive regulator of ACC. SDS-polyacrylamide gel electrophoresis of both homogenates and immunopellets from these muscles showed a decrease in the electrophoretic mobility of ACC, suggesting that phosphorylation could account for the decrease in ACC activity. In keeping with this notion, citrate activation of ACC purified from contracting muscle was markedly depressed. In addition, homogenization of the muscles in a buffer free of phosphatase inhibitors and containing the phosphatase activators glutamate and MgCl2 or treatment of immunoprecipitated ACC-beta with purified protein phosphatase 2A abolished the decreases in both ACC-beta activity and electrophoretic mobility caused by contraction. The rapid decrease in ACC-beta activity after the onset of contractions (50% by 20 s) and its slow restoration to initial values during recovery (60-90 min) were paralleled temporally by reciprocal changes in the activity of the alpha2 but not the alpha1 isoform of 5'-AMP-activated protein kinase (AMPK). In conclusion, the results suggest that the decrease in ACC activity during muscle contraction is caused by an increase in its phosphorylation, most probably due, at least in part, to activation of the alpha2 isoform of AMPK. They also suggest a dual mechanism for ACC regulation in muscle in which inhibition by phosphorylation takes precedence over activation by citrate. These alterations in ACC and AMPK activity, by diminishing the concentration of malonyl-CoA, could be responsible for the increase in fatty acid oxidation observed in skeletal muscle during exercise.
Coping with Self-Threat and the Evaluation of Self-Related Traits: An fMRI Study
Corcoran, Katja; Ebner, Franz
2015-01-01
A positive view of oneself is important for a healthy lifestyle. Self-protection mechanisms such as suppressing negative self-related information help us to maintain a positive view of ourselves. This is of special relevance when, for instance, a negative test result threatens our positive self-view. To date, it is not clear which brain areas support self-protective mechanisms under self-threat. In the present functional magnetic resonance imaging (fMRI) study the participants (N = 46) received a (negative vs. positive) performance test feedback before entering the scanner. In the scanner, the participants were instructed to ascribe personality traits either to themselves or to a famous other. Our results showed that participants responded slower to negative self-related traits compared to positive self-related traits. High self-esteem individuals responded slower to negative traits compared to low self-esteem individuals following a self-threat. This indicates that high self-esteem individuals engage more in self-enhancing strategies after a threat by inhibiting negative self-related information more successfully than low self-esteem individuals. This behavioral pattern was mirrored in the fMRI data as dACC correlated positively with trait self-esteem. Generally, ACC activation was attenuated under threat when participants evaluated self-relevant traits and even more for negative self-related traits. We also found that activation in the ACC was negatively correlated with response times, indicating that greater activation of the ACC is linked to better access (faster response) to positive self-related traits and to impaired access (slower response) to negative self-related traits. These results confirm the ACC function as important in managing threatened self-worth but indicate differences in trait self-esteem levels. The fMRI analyses also revealed a decrease in activation within the left Hippocampus and the right thalamus under threat. This indicates that a down-regulation of activation in these regions might also serve as coping mechanism in dealing with self-threat. PMID:26333130
Zhang, Li; Mitani, Yoshitsugu; Caulin, Carlos; Rao, Pulivarthi H; Kies, Merrill S; Saintigny, Pierre; Zhang, Nianxiang; Weber, Randal S; Lippman, Scott M; El-Naggar, Adel K
2013-06-01
The molecular genetic alterations underlying the development and diversity of salivary gland carcinomas are largely unknown. To characterize these events, comparative genomic hybridization analysis was performed, using a single-nucleotide polymorphism microarray platform, of 60 fresh-frozen specimens that represent the main salivary carcinoma types: mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and salivary duct carcinoma (SDC). The results were correlated with the clinicopathologic features and translocation statuses to characterize the genetic alterations. The most commonly shared copy number abnormalities (CNAs) in all types were losses at chromosomes 6q23-26 and the 9p21 region. Subtype-specific CNAs included a loss at 12q11-12 in ACC and a gain at 17q11-12 in SDC. Focal copy number losses included 1p36.33-p36-22 in ACC, 9p13.2 in MEC, and 3p12.3-q11-2, 6q21-22.1, 12q14.1, and 12q15 in SDC. Tumor-specific amplicons were identified at 11q23.3 (PVRL1) in ACC, 11q13.3 (NUMA1) in MEC, and 6p21.1 (CCND3), 9p13.2 (PAX5), 12q15 (CNOT2/RAB3IP), 12q21.1 (GLIPR1L1), and 17q12 (ERBB2/CCL4) in SDC. A comparative CNA analysis of fusion-positive and fusion-negative ACCs and MECs revealed relatively lower CNAs in fusion-positive tumors than in fusion-negative tumors in both tumor types. An association between CNAs and high grade and advanced stage was observed in MECs only. These findings support the pathogenetic segregation of these entities and define novel chromosomal sites for future identification of biomarkers and therapeutic targets. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
Victor, Teresa A; Furey, Maura L; Fromm, Stephen J; Öhman, Arne; Drevets, Wayne C
2013-11-01
An emerging hypothesis regarding the mechanisms underlying antidepressant pharmacotherapy suggests that these agents benefit depressed patients by reversing negative emotional processing biases (Harmer, 2008). Neuropsychological indices and functional neuroimaging measures of the amygdala response show that antidepressant drugs shift implicit and explicit processing biases away from the negative valence and toward the positive valence. However, few studies have explored such biases in regions extensively connected with the amygdala, such as the pregenual anterior cingulate cortex (pgACC) area, where pre-treatment activity consistently has predicted clinical outcome during antidepressant treatment. We used functional magnetic resonance imaging (fMRI) to investigate changes in haemodynamic response patterns to positive vs. negative stimuli in patients with major depressive disorder (MDD) under antidepressant treatment. Participants with MDD (n = 10) underwent fMRI before and after 8 wk sertraline treatment; healthy controls (n = 10) were imaged across an equivalent interval. A backward masking task was used to elicit non-conscious neural responses to sad, happy and neutral face expressions. Haemodynamic responses to emotional face stimuli were compared between conditions and groups in the pgACC. The response to masked-sad vs. masked-happy faces (SN-HN) in pgACC in the depressed subjects was higher in the pre-treatment condition than in the post-treatment condition and this difference was significantly greater than the corresponding change across time in the controls. The treatment-associated difference was attributable to an attenuated response to sad faces and an enhanced response to happy faces. Pre-treatment pgACC responses to SN-HN correlated positively with clinical improvement during treatment. The pgACC participates with the amygdala in processing the salience of emotional stimuli. Treatment-associated functional changes in this limbic network may influence the non-conscious processing of such stimuli by reversing the negative processing bias extant in MDD.
Impact of Emotion on Consciousness: Positive Stimuli Enhance Conscious Reportability
Rømer Thomsen, Kristine; Lou, Hans C.; Joensson, Morten; Hyam, Jonathan A.; Holland, Peter; Parsons, Christine E.; Young, Katherine S.; Møller, Arne; Stein, Alan; Green, Alex L.; Kringelbach, Morten L.; Aziz, Tipu Z.
2011-01-01
Emotion and reward have been proposed to be closely linked to conscious experience, but empirical data are lacking. The anterior cingulate cortex (ACC) plays a central role in the hedonic dimension of conscious experience; thus potentially a key region in interactions between emotion and consciousness. Here we tested the impact of emotion on conscious experience, and directly investigated the role of the ACC. We used a masked paradigm that measures conscious reportability in terms of subjective confidence and objective accuracy in identifying the briefly presented stimulus in a forced-choice test. By manipulating the emotional valence (positive, neutral, negative) and the presentation time (16 ms, 32 ms, 80 ms) we measured the impact of these variables on conscious and subliminal (i.e. below threshold) processing. First, we tested normal participants using face and word stimuli. Results showed that participants were more confident and accurate when consciously seeing happy versus sad/neutral faces and words. When stimuli were presented subliminally, we found no effect of emotion. To investigate the neural basis of this impact of emotion, we recorded local field potentials (LFPs) directly in the ACC in a chronic pain patient. Behavioural findings were replicated: the patient was more confident and accurate when (consciously) seeing happy versus sad faces, while no effect was seen in subliminal trials. Mirroring behavioural findings, we found significant differences in the LFPs after around 500 ms (lasting 30 ms) in conscious trials between happy and sad faces, while no effect was found in subliminal trials. We thus demonstrate a striking impact of emotion on conscious experience, with positive emotional stimuli enhancing conscious reportability. In line with previous studies, the data indicate a key role of the ACC, but goes beyond earlier work by providing the first direct evidence of interaction between emotion and conscious experience in the human ACC. PMID:21494569
Impaired cortico-limbic functional connectivity in schizophrenia patients during emotion processing.
Comte, Magali; Zendjidjian, Xavier Y; Coull, Jennifer T; Cancel, Aïda; Boutet, Claire; Schneider, Fabien C; Sage, Thierry; Lazerges, Pierre-Emmanuel; Jaafari, Nematollah; Ibrahim, El Chérif; Azorin, Jean-Michel; Blin, Olivier; Fakra, Eric
2017-10-23
Functional dysconnection is increasingly recognized as a core pathological feature in schizophrenia. Aberrant interactions between regions of the cortico-limbic circuit may underpin the abnormal emotional processing associated with this illness. We used a functional magnetic resonance imaging (fMRI) paradigm designed to dissociate the various components of the cortico-limbic circuit (i.e. a ventral automatic circuit that is intertwined with a dorsal cognitive circuit), in order to explore bottom-up appraisal as well as top-down control during emotion processing. In schizophrenia patients compared to healthy controls, bottom-up processes were associated with reduced interaction between the amygdala and both the anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC). Contrariwise, top-down control processes led to stronger connectivity between the ventral affective and the dorsal cognitive circuits, i.e. heightened interactions between the ventral ACC and the DLPFC as well as between dorsal and ventral ACC. These findings offer a comprehensive view of the cortico-limbic dysfunction in schizophrenia. They confirm previous results of impaired propagation of information between the amygdala and the prefrontal cortex and suggest a defective functional segregation in the dorsal cognitive part of the cortico-limbic circuit. © The Author (2017). Published by Oxford University Press.
Impaired cortico-limbic functional connectivity in schizophrenia patients during emotion processing
Comte, Magali; Zendjidjian, Xavier Y; Coull, Jennifer T; Cancel, Aïda; Boutet, Claire; Schneider, Fabien C; Sage, Thierry; Lazerges, Pierre-Emmanuel; Jaafari, Nematollah; Ibrahim, El Chérif; Azorin, Jean-Michel; Blin, Olivier; Fakra, Eric
2018-01-01
Abstract Functional dysconnection is increasingly recognized as a core pathological feature in schizophrenia. Aberrant interactions between regions of the cortico-limbic circuit may underpin the abnormal emotional processing associated with this illness. We used a functional magnetic resonance imaging paradigm designed to dissociate the various components of the cortico-limbic circuit (i.e. a ventral automatic circuit that is intertwined with a dorsal cognitive circuit), to explore bottom-up appraisal as well as top-down control during emotion processing. In schizophrenia patients compared with healthy controls, bottom-up processes were associated with reduced interaction between the amygdala and both the anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex. Contrariwise, top-down control processes led to stronger connectivity between the ventral affective and the dorsal cognitive circuits, i.e. heightened interactions between the ventral ACC and the dorsolateral prefrontal cortex as well as between dorsal and ventral ACC. These findings offer a comprehensive view of the cortico-limbic dysfunction in schizophrenia. They confirm previous results of impaired propagation of information between the amygdala and the prefrontal cortex and suggest a defective functional segregation in the dorsal cognitive part of the cortico-limbic circuit. PMID:29069508
Mechanism for the Inhibition of the Carboxyl-transferase
DOE Office of Scientific and Technical Information (OSTI.GOV)
L Yu; Y Kim; L Tong
Acetyl-CoA carboxylases (ACCs) are crucial metabolic enzymes and have been targeted for drug development against obesity, diabetes, and other diseases. The carboxyltransferase (CT) domain of this enzyme is the site of action for three different classes of herbicides, as represented by haloxyfop, tepraloxydim, and pinoxaden. Our earlier studies have demonstrated that haloxyfop and tepraloxydim bind in the CT active site at the interface of its dimer. However, the two compounds probe distinct regions of the dimer interface, sharing primarily only two common anchoring points of interaction with the enzyme. We report here the crystal structure of the CT domain ofmore » yeast ACC in complex with pinoxaden at 2.8-{angstrom} resolution. Despite their chemical diversity, pinoxaden has a similar binding mode as tepraloxydim and requires a small conformational change in the dimer interface for binding. Crystal structures of the CT domain in complex with all three classes of herbicides confirm the importance of the two anchoring points for herbicide binding. The structures also provide a foundation for understanding the molecular basis of the herbicide resistance mutations and cross resistance among the herbicides, as well as for the design and development of new inhibitors against plant and human ACCs.« less
Chen, Haifei; Zhang, Quan; Cai, Hongmei; Xu, Fangsen
2017-01-01
pH is an important factor regulating plant growth. Here, we found that rice was better adapted to low pH than alkaline conditions, as its growth was severely inhibited at high pH, with shorter root length and an extreme biomass reduction. Under alkaline stress, the expression of genes for ethylene biosynthesis enzymes in rice roots was strongly induced by high pH and exogenous ethylene precursor ACC and ethylene overproduction in etol1-1 mutant aggravated the alkaline stress-mediated inhibition of rice growth, especially for the root elongation with decreased cell length in root apical regions. Conversely, the ethylene perception antagonist silver (Ag+) and ein2-1 mutants could partly alleviate the alkaline-induced root elongation inhibition. The H+-ATPase activity was extremely inhibited by alkaline stress and exogenous ACC. However, the H+-ATPase-mediated rhizosphere acidification was enhanced by exogenous Ag+, while H+ efflux on the root surface was extremely inhibited by exogenous ACC, suggesting that ethylene negatively regulated H+-ATPase activity under high-pH stress. Our results demonstrate that H+-ATPase is involved in ethylene-mediated inhibition of rice growth under alkaline stress. PMID:29114258
Watanabe, Keiko; Masaoka, Yuri; Kawamura, Mitsuru; Yoshida, Masaki; Koiwa, Nobuyoshi; Yoshikawa, Akira; Kubota, Satomi; Ida, Masahiro; Ono, Kenjiro; Izumizaki, Masahiko
2018-01-01
Autobiographical odor memory (AM-odor) accompanied by a sense of realism of a specific memory elicits strong emotions. AM-odor differs from memory triggered by other sensory modalities, possibly because olfaction involves a unique sensory process. Here, we examined the orbitofrontal cortex (OFC), using functional magnetic resonance imaging (fMRI) to determine which OFC subregions are related to AM-odor. Both AM-odor and a control odor successively increased subjective ratings of comfortableness and pleasantness. Importantly, AM-odor also increased arousal levels and the vividness of memories, and was associated with a deep and slow breathing pattern. fMRI analysis indicated robust activation in the left posterior OFC (L-POFC). Connectivity between the POFC and whole brain regions was estimated using psychophysiological interaction analysis (PPI). We detected several trends in connectivity between L-POFC and bilateral precuneus, bilateral rostral dorsal anterior cingulate cortex (rdACC), and left parahippocampus, which will be useful for targeting our hypotheses for future investigations. The slow breathing observed in AM-odor was correlated with rdACC activation. Odor associated with emotionally significant autobiographical memories was accompanied by slow and deep breathing, possibly involving rdACC processing.
Theta signal as the neural signature of social exclusion.
Cristofori, Irene; Moretti, Laura; Harquel, Sylvain; Posada, Andres; Deiana, Gianluca; Isnard, Jean; Mauguière, François; Sirigu, Angela
2013-10-01
The feeling of being excluded from a social interaction triggers social pain, a sensation as intense as actual physical pain. Little is known about the neurophysiological underpinnings of social pain. We addressed this issue using intracranial electroencephalography in 15 patients performing a ball game where inclusion and exclusion blocks were alternated. Time-frequency analyses showed an increase in power of theta-band oscillations during exclusion in the anterior insula (AI) and posterior insula, the subgenual anterior cingulate cortex (sACC), and the fusiform "face area" (FFA). Interestingly, the AI showed an initial fast response to exclusion but the signal rapidly faded out. Activity in the sACC gradually increased and remained significant thereafter. This suggests that the AI may signal social pain by detecting emotional distress caused by the exclusion, whereas the sACC may be linked to the learning aspects of social pain. Theta activity in the FFA was time-locked to the observation of a player poised to exclude the participant, suggesting that the FFA encodes the social value of faces. Taken together, our findings suggest that theta activity represents the neural signature of social pain. The time course of this signal varies across regions important for processing emotional features linked to social information.