38 research outputs found

    Network-Level Structural Abnormalities of Cerebral Cortex in Type 1 Diabetes Mellitus

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    Type 1 diabetes mellitus (T1DM) usually begins in childhood and adolescence and causes lifelong damage to several major organs including the brain. Despite increasing evidence of T1DM-induced structural deficits in cortical regions implicated in higher cognitive and emotional functions, little is known whether and how the structural connectivity between these regions is altered in the T1DM brain. Using inter-regional covariance of cortical thickness measurements from high-resolution T1-weighted magnetic resonance data, we examined the topological organizations of cortical structural networks in 81 T1DM patients and 38 healthy subjects. We found a relative absence of hierarchically high-level hubs in the prefrontal lobe of T1DM patients, which suggests ineffective top-down control of the prefrontal cortex in T1DM. Furthermore, inter-network connections between the strategic/executive control system and systems subserving other cortical functions including language and mnemonic/emotional processing were also less integrated in T1DM patients than in healthy individuals. The current results provide structural evidence for T1DM-related dysfunctional cortical organization, which specifically underlie the top-down cognitive control of language, memory, and emotion. © 2013 Lyoo et al

    Open-label study comparing the efficacy and tolerability of aripiprazole and haloperidol in the treatment of pediatric tic disorders

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    Due to its unique pharmacodynamic properties of dopamine partial agonist activity, and its association with few and mild side effects, aripiprazole is a candidate atypical antipsychotic for patients with tic disorders. This open-label study compared the efficacy and tolerability of aripiprazole with haloperidol, a typical antipsychotic widely used to treat patients with tic disorders. Forty-eight children and adolescents with tic disorders were recruited from the outpatient clinic at South Korea and treated with aripiprazole (initial dose, 5.0 mg/d; maximum dose 20 mg/d) or haloperidol (initial dose, 0.75 mg/d; maximum dose, 4.5 mg/d) for 8 weeks. Treatment efficacy was measured using the yale global tic severity scale (YGTSS), and tolerability was measured using the extrapyramidal symptom rating scale (ESRS) and an adverse effects checklist. Total tic scores as measured by the YGTSS decreased over time in both groups (p < 0.001) without any significant differences between groups. ESRS scores were significantly higher in the haloperidol group during the 4 weeks after commencement of medication (p < 0.05). These results indicate that aripiprazole may be a promising drug in the treatment of children and adolescents with tic disorders. Further controlled studies are needed to determine the efficacy and tolerability of aripiprazole in these patients

    New Era of Air Quality Monitoring from Space: Geostationary Environment Monitoring Spectrometer (GEMS)

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    GEMS will monitor air quality over Asia at unprecedented spatial and temporal resolution from GEO for the first time, providing column measurements of aerosol, ozone and their precursors (nitrogen dioxide, sulfur dioxide and formaldehyde). Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in late 2019 - early 2020 to monitor Air Quality (AQ) at an unprecedented spatial and temporal resolution from a Geostationary Earth Orbit (GEO) for the first time. With the development of UV-visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO and aerosols) can be obtained. To date, all the UV-visible satellite missions monitoring air quality have been in Low Earth orbit (LEO), allowing one to two observations per day. With UV-visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be onboard the GEO-KOMPSAT-2 satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager (GOCI)-2. These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA&apos;s TEMPO and ESA&apos;s Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS)

    Decreased glutamate/glutamine levels may mediate cytidine's efficacy in treating bipolar depression: a longitudinal proton magnetic resonance spectroscopy study

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    Targeting the glutamatergic system has been suggested as a promising new option for developing treatment strategies for bipolar depression. Cytidine, a pyrimidine, may exert therapeutic effects through a pathway that leads to altered neuronal-glial glutamate cycling. Pyrimidines are also known to exert beneficial effects on cerebral phospholipid metabolism, catecholamine synthesis, and mitochondrial function, which have each been linked to the pathophysiology of bipolar depression. This study was aimed at determining cytidine's efficacy in bipolar depression and at assessing the longitudinal effects of cytidine on cerebral glutamate/glutamine levels. Thirty-five patients with bipolar depression were randomly assigned to receive the mood-stabilizing drug valproate plus either cytidine or placebo for 12 weeks. Midfrontal cerebral glutamate/glutamine levels were measured using proton magnetic resonance spectroscopy before and after 2, 4, and 12 weeks of oral cytidine administration. Cytidine supplementation was associated with an earlier improvement in depressive symptoms (weeks 1-4; p=0.02, 0.001, 0.002, and 0.004, respectively) and also produced a greater reduction in cerebral glutamate/glutamine levels in patients with bipolar depression (weeks 2, 4, and 12; p=0.004, 0.004, and 0.02, respectively). Cytidine-related glutamate/glutamine decrements correlated with a reduction in depressive symptoms (p=0.001). In contrast, these relationships were not observed in the placebo add-on group. The study results suggest that cytidine supplementation of valproate is associated with an earlier treatment response in bipolar depression. Furthermore, cytidine's efficacy in bipolar depression may be mediated by decreased levels of cerebral glutamate and/or glutamine, consistent with alterations in excitatory neurotransmission

    Clinical response of quetiapine in rapid cycling manic bipolar patients and lactate level changes in proton magnetic resonance spectroscopy

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    The aim of the current study was to evaluate the relationship between quetiapine's effect on the improvement of mood symptoms in bipolar patients and brain metabolite level changes as measured by proton magnetic resonance spectroscopy ((1)H-MRS). Rapid cycling bipolar patients in the manic state were recruited and treated with quetiapine for 12 weeks. Clinical assessment was performed using the Young Mania Rating Scale (YMRS), the 17-item Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impression-Severity scale (CGI-S) at baseline and weekly intervals during the 12-week period. In order to evaluate metabolite level changes over time, (1)H-MRS scans were acquired at baseline and week 12. There were significant reductions in YMRS scores (by 43.0%), HDRS scores (by 27.5%) and CGI-S score (by 44.6%) over the 12 week-period. Lactate levels significantly decreased over the 12-week study period (22.4%). This change in lactate levels was more prominent in quetiapine responders than in non-responders. Additionally, there was a positive correlation between changes in lactate levels and those in YMRS scores (r=0.52, p=0.003). Our findings suggest that quetiapine's antimanic and antidepressant efficacy in patients with rapid cycling bipolar disorder may potentially be related to decreased lactate levels in frontal regions of the brain

    Diminished rostral anterior cingulate activity in response to threat-related events in posttraumatic stress disorder

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    BACKGROUND: Previous brain imaging studies have reported hyperactivation of the amygdala and hypoactivation of the anterior cingulate in posttraumatic stress disorder (PTSD) patients, which is believed to be an underlying neural mechanism of the PTSD symptoms. The current study specifically focuses on the abnormal activity of the rostral anterior cingulate, using a paradigm which elicits an unexpected processing conflict caused by salient emotional stimuli. METHODS: Twelve survivors (seven men and five women) of the Taegu subway fire in 2003, who later developed PTSD, agreed to participate in this study. Twelve healthy volunteers (seven men and five women) were recruited for comparison. Functional brain images of all participants were acquired using functional magnetic resonance imaging while performing a same-different judgment task, which was modified to elicit an unexpected emotional processing conflict. RESULTS: PTSD patients, compared to comparison subjects, showed a decreased rostral anterior cingulate functioning when exposed to situations which induce an unexpected emotional processing conflict. Moreover, PTSD symptom severity was negatively correlated to the level of decrease in the rostral anterior cingulate activity. CONCLUSIONS: The results of this study provide evidence that the rostral anterior cingulate functioning is impaired in PTSD patients during response-conflict situations that involve emotional stimuli

    Neurochemical Alterations in Methamphetamine-Dependent Patients Treated with Cytidine-5 `-Diphosphate Choline: A Longitudinal Proton Magnetic Resonance Spectroscopy Study

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    Cytidine-5`-diphosphate choline (CDP-choline), as an important intermediate for major membrane phospholipids, may exert neuroprotective effects in various neurodegenerative disorders. This longitudinal proton magnetic resonance spectroscopy ((1)H-MRS) study aimed to examine whether a 4-week CDP-choline treatment could alter neurometabolite levels in patients with methamphetamine (MA) dependence and to investigate whether changes in neurometabolite levels would be associated with MA use. We hypothesized that the prefrontal levels of N-acetyl-aspartate (NAA), a neuronal marker, and choline-containing compound (Cho), which are related to membrane turnover, would increase with CDP-choline treatment in MA-dependent patients. We further hypothesized that this increase would correlate with the total number of negative urine results. Thirty-one treatment seekers with MA dependence were randomly assigned to receive CDP-choline (n = 16) or placebo (n 15) for 4 weeks. Prefrontal NAA and Cho levels were examined using (1)H-MRS before medication, and at 2 and 4 weeks after treatment. Generalized estimating equation regression analyses showed that the rate of change in prefrontal NAA (p = 0.005) and Cho (p = 0.03) levels were greater with CDP-choline treatment than with placebo. In the CDP-choline-treated patients, changes in prefrontal NAA levels were positively associated with the total number of negative urine results (p = 0.03). Changes in the prefrontal Cho levels, however, were not associated with the total number of negative urine results. These preliminary findings suggest that CDP-choline treatment may exert potential neuroprotective effects directly or indirectly because of reductions in drug use by the MA-dependent patients. Further studies with a larger sample size of MA-dependent patients are warranted to confirm a long-term efficacy of CDP-choline in neuroprotection and abstinence. Neuropsychopharmacology (2010) 35, 1165-1173; doi: 10.1038/npp.2009.221; published online 30 December 2009This study was supported in part by grants from the NIDA (1R01 DA024070-01A1, Drs Lyoo and Renshaw; 5 R01 DA 14178-05, Dr Renshaw), from the NIH (7K24DA015116, Dr Renshaw; 5K05-DA000343-12, Dr Lukas), from the Korean Ministry of Education, Science and Technology, (2009K001272, Dr Lyoo; Basic Science Research Program 20090066915, Dr Yoon), and from Seoul National University Hospital (03-2008-006-0, Dr Lyoo).Yoon SJ, 2009, NEUROPSYCHOPHARMACOL, V34, P1810, DOI 10.1038/npp.2009.2Tian CH, 2009, PLOS ONE, V4, DOI 10.1371/journal.pone.0005546Silveri MM, 2008, NMR BIOMED, V21, P1066, DOI 10.1002/nbm.1281Bustillo JR, 2008, NEUROPSYCHOPHARMACOL, V33, P2456, DOI 10.1038/sj.npp.1301631Mathew SJ, 2008, BIOL PSYCHIAT, V63, P891, DOI 10.1016/j.biopsych.2007.09.012Berman S, 2008, ANN NY ACAD SCI, V1141, P195, DOI 10.1196/annals.1441.031Lee NK, 2008, DRUG ALCOHOL REV, V27, P309, DOI 10.1080/09595230801919494PROVENCHER SW, 2008, LCMODEL USERS MANUAL*DRUG ENF ADM, 2008, NAT DRUG THREAT ASSChung A, 2007, INT J NEUROPSYCHOPH, V10, P765, DOI 10.1017/Sl461145706007395Brown ES, 2007, J CLIN PSYCHOPHARM, V27, P498, DOI 10.1097/jcp.0b013e31814db4c4Scott JC, 2007, NEUROPSYCHOL REV, V17, P275, DOI 10.1007/s11065-007-9031-0Radad K, 2007, INT J NEUROSCI, V117, P985, DOI 10.1080/10623320600934341Salo R, 2007, BIOL PSYCHIAT, V61, P1272, DOI 10.1016/j.biopsych.2006.07.031Sung YH, 2007, DRUG ALCOHOL DEPEN, V88, P28, DOI 10.1016/j.drugalcdep.2006.09.011Vocci FJ, 2007, ADDICTION, V102, P96Ham BJ, 2007, EUR J NEUROSCI, V25, P324, DOI 10.1111/j.1460-9568.2006.05253.xShearer J, 2007, J SUBST ABUSE TREAT, V32, P41, DOI 10.1016/j.jsat.2006.06.012*DRUG ENF ADM, 2007, NAT DRUG THREAT ASSSecades JJ, 2006, METHOD FIND EXP CLIN, V28, P1Hwang J, 2006, DRUG ALCOHOL DEPEN, V82, P177, DOI 10.1016/j.drugalcdep.2005.09.011Kim SJ, 2006, INT J NEUROPSYCHOPH, V9, P221, DOI 10.1017/S1461145705005699Grohman K, 2006, BRAIN COGNITION, V60, P203Poling J, 2006, ARCH GEN PSYCHIAT, V63, P219Bae SC, 2006, DRUG ALCOHOL DEPEN, V81, P83, DOI 10.1016/j.drugalcdep.2005.05.016QUINTON MS, 2006, AAPS J, V8, P337Kim SJ, 2005, NEUROPSYCHOPHARMACOL, V30, P1383, DOI 10.1038/sj.npp.1300699Meredith CW, 2005, HARVARD REV PSYCHIAT, V13, P141, DOI 10.1080/10673220591003605Nordahl TE, 2005, ARCH GEN PSYCHIAT, V62, P444Chang L, 2005, AM J PSYCHIAT, V162, P361Adibhatla R, 2005, NEUROCHEM RES, V30, P15, DOI 10.1007/s11064-004-9681-8*NSDUH, 2005, RES 2005 NSUDHBrown JM, 2003, PHARMACOL THERAPEUT, V99, P45, DOI 10.1016/S0163-7258(03)00052-4BARREDA V, 2003, REV MUSEO ARGENTINO, V5, P215Barrachina M, 2002, BRAIN RES, V957, P84Nordahl TE, 2002, PSYCHIAT RES-NEUROIM, V116, P43Ross BM, 2002, DRUG ALCOHOL DEPEN, V67, P73Babb SM, 2002, PSYCHOPHARMACOLOGY, V161, P248, DOI 10.1007/s00213-002-1045-yRoss BM, 2002, PROSTAG LEUKOTR ESS, V66, P479, DOI 10.1054/plef.385FIRST MB, 2002, STRUCTURAL CLIN INTEClark WM, 2001, NEUROLOGY, V57, P1595Lukas SE, 2001, PSYCHOPHARMACOLOGY, V157, P163Davidson C, 2001, BRAIN RES REV, V36, P1McLean MA, 2001, NEUROIMAGE, V14, P501, DOI 10.1006/nimg.2001.0827Smith LM, 2001, NEUROLOGY, V57, P255Provencher SW, 2001, NMR BIOMED, V14, P260Bertolino A, 2001, BIOL PSYCHIAT, V49, P39Wurtman RJ, 2000, BIOCHEM PHARMACOL, V60, P989Rawson RA, 2000, J PSYCHOACTIVE DRUGS, V32, P371Boulanger Y, 2000, BRAIN RES REV, V33, P380Moore GJ, 2000, BIOL PSYCHIAT, V48, P1Ernst T, 2000, NEUROLOGY, V54, P1344Winsberg ME, 2000, BIOL PSYCHIAT, V47, P475Bluml S, 1999, MAGNET RESON MED, V42, P643Clement JM, 1999, BIOCHEM BIOPH RES CO, V257, P643Renshaw PF, 1999, PSYCHOPHARMACOLOGY, V142, P132Clark JB, 1998, DEV NEUROSCI-BASEL, V20, P271Deicken RF, 1998, BIOL PSYCHIAT, V43, P483Araki W, 1998, J NEUROSCI RES, V51, P667Murray JB, 1998, J PSYCHOL, V132, P227Ellis CM, 1997, NEUROLOGY, V49, P438Hussain T, 1997, CLIN EXP HYPERTENS, V19, P131Christensen JD, 1996, MAGNET RESON MED, V35, P658Reid MS, 1996, J PHARMACOL EXP THER, V276, P1244ROSS K, 1996, PARALLAX, V2, P67DESTEFANO N, 1995, MAGNET RESON MED, V34, P721VIAL D, 1995, J NEUROCHEM, V64, P2765HOLSHOUSER BA, 1995, MAGNET RESON MED, V33, P589WEISS GB, 1995, LIFE SCI, V56, P637VIONDURY J, 1995, LANCET, V345, P60DAVIE CA, 1994, BRAIN, V117, P49MACKAY S, 1993, BIOL PSYCHIAT, V34, P261MCALLISTER G, 1993, FEBS LETT, V324, P81BARKER PB, 1993, NMR BIOMED, V6, P89OMALLEY SS, 1992, ARCH GEN PSYCHIAT, V49, P881WANG AM, 1990, AM J NEURORADIOL, V11, P1141ZEGER SL, 1986, BIOMETRICS, V42, P121TRUCKENMILLER ME, 1985, J NEUROCHEM, V45, P1658SALIGAUT C, 1985, METHOD FIND EXP CLIN, V7, P5AGUT J, 1984, NEUROPHARMACOLOGY, V23, P1403ALBERGHINA M, 1981, J NEUROSCI RES, V6, P421PATEL TB, 1979, BIOCHEM J, V184, P539MARTINET M, 1979, ARCH INT PHARMACOD T, V239, P52MARTINET M, 1978, EXPERIENTIA, V34, P1197HAMILTON M, 1960, J NEUROL NEUROSUR PS, V23, P56KENNEDY EP, 1956, J BIOL CHEM, V222, P193

    Lovastatin potentiates the antidepressant efficacy of fluoxetine in rats

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    BACKGROUND: Cholesterol may have a role in the pathophysiology of depression. Lowering cholesterol levels with statins reduces risks for cardiovascular events, and there is clinical evidence that statins exert neuroprotective properties not fully explained by their effects on serum cholesterol levels. Altered cholesterol levels can affect serotonergic neurotransmission, which might be involved in the clinical efficacy of standard antidepressants. METHODS: We examined interactions between a statin (lovastatin) and a selective serotonin reuptake inhibitor (fluoxetine) using the forced swim test (FST) in rats, a behavioral assay that identifies treatments with antidepressant effects in humans. Specifically, we determined if the addition of lovastatin to the diet would increase the efficacy of a subeffective dose of fluoxetine. RESULTS: Rats maintained on a lovastatin-enriched diet for 30 days were more sensitive to the antidepressant-like effects of a low (subthreshold) dose of fluoxetine. The behavior of rats treated with this combination resembled that normally seen with higher doses of fluoxetine. No effects were observed in rats maintained on a lovastatin-enriched diet for 3 days. CONCLUSIONS: Lovastatin can augment the antidepressant-like effects of a low dose of fluoxetine in rats, raising the possibility that statins could be used to facilitate the effects of antidepressants in humans

    Enlarged cavum septum pellucidum as a neurodevelopmental marker in adolescent-onset opiate dependence.

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    Adolescent-onset exposure to highly addictive substances such as opiates may induce far-reaching deleterious effects on later mental and physical health. However, little is known about the neurodevelopmental basis for adolescent-onset opiate dependence. Here we examined whether having an abnormally large cavum septum pellucidum (CSP), a putative marker of limbic structural maldevelopment, is associated with opiate dependence particularly beginning in adolescence.The overall length of the CSP and the prevalence of abnormal enlargement of the CSP were assessed and compared in 65 opiate-dependent subjects (41 adolescent-onset opiate users and 24 adult-onset opiate users) and 67 healthy subjects.Opiate-dependent subjects showed a greater prevalence of abnormal CSP enlargement relative to healthy subjects (odds ratio [OR]=3.64, p=0.034). The overall CSP length of adolescent-onset opiate-dependent subjects was greater, as compared not only with healthy subjects (F₁,₁₀₄=11.03, p=0.001) but also with those who began opiate use during adulthood (F₁,₆₁=4.43, p=0.039).The current findings provide the first evidence that abnormal CSP enlargement, which reflects limbic system dysgenesis of neurodevelopmental origin, may be linked to later development of opiate dependence. In addition, a greater CSP length, which indicates more severe limbic abnormalities, appears to confer higher risk for earlier onset of opiate use

    A preliminary study: novelty seeking, frontal executive function, and dopamine receptor (D2) TaqI A gene polymorphism in patients with methamphetamine dependence

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    INTRODUCTION: Dopamine receptor polymorphisms have been associated with specific patterns of novelty seeking (NS) temperamental nature and frontal executive function. In addition, carriers of dopamine receptor type 2 (DRD2)-TaqI A1 have been hypothesized to be potentially vulnerable to addictive behaviors. In the present study, the association between dopamine D2 polymorphisms, NS, and frontal executive function was studied. METHODS: Thirty-seven methamphetamine (MA)-dependent subjects and 40 healthy comparison subjects participated in the current study. The severity of addiction, NS temperament, and frontal executive functions were measured using the Addiction Severity Index, the NS subscale in the Temperament and Character Inventory, and the Wisconsin Card Sorting Test, respectively. All subjects were genotyped with regard to DRD2-TaqI polymorphisms. RESULTS: The prevalence of DRD2-TaqI A1 allele polymorphisms was greater in the MA-abuser group than in the comparison group. Patients with MA dependence also had higher NS characteristics and high scores in total trials, errors, and perseverative errors of the Wisconsin Card Sorting Test than comparison subjects. Within patients with MA dependence, the subgroup of DRD2-TaqI A1 carrier had greater NS scores relative to those without, whereas there was only a trend level of lower frontal executive function in the first subgroup. CONCLUSION: In the present study, the MA-dependent patients with DRD2-TaqI A1 allele had significantly greater NS scores and lower frontal executive function with a trend level than those without. These preliminary results suggest that MA-dependent patients may have the possibility of genetic and biogenic vulnerability to MA
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