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1.
Vet Radiol Ultrasound ; 64(4): 646-660, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37280763

RESUMO

This two-part study design showed that a canine congenital intrahepatic portosystemic shunt (IPSS) may be classified by its location within a liver fissure (interlobar) or lobe (intralobar). A prospective anatomic study reviewed normal canine liver morphology and showed the CT angiography (CTA) appearance of the normal canine ductus venosus (DV), which was confirmed via dissection and literature review to be between the papillary process and left-lateral liver lobe (in the fissure for ligamentum venosum). A retrospective multi-institutional case series documented the frequency of imaging findings in 56 dogs with a single IPSS that underwent portal CTA at Cornell University or the Schwarzman Animal Medical Center between June 2008 and August 2022. An interlobar IPSS was seen in 24 of 56 (43%) dogs, all arose from the left portal branch except one. These shunts were typically near the median plane, remained interlobar throughout the course, and were nearly always (96%) craniodorsal to the porta hepatis. Four types were distinguished: patent DV (11 dogs), left interlobar (11 dogs), right interlobar (1 dog), and ventral interlobar (1 dog). Only about half (46%) were in the fissure for ligamentum venosum and therefore classified as a patent DV. An intralobar IPSS was seen in 32 of 56 (57%) dogs, most (88%) originated from the right portal branch and were in the right-lateral liver lobe (21 dogs) or caudate process (7 dogs). During canine portal CTA, documenting the interlobar or intralobar location of an IPSS might increase the consistency and validity of IPSS description.


Assuntos
Derivação Portossistêmica Transjugular Intra-Hepática , Cães , Animais , Derivação Portossistêmica Transjugular Intra-Hepática/veterinária , Estudos Retrospectivos , Estudos Prospectivos , Veia Porta/diagnóstico por imagem
2.
J Pharm Pract ; 35(1): 26-31, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32648514

RESUMO

BACKGROUND: Little evidence is available regarding the choice of empiric antibiotic therapy in elderly patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The primary objective of this study is to compare the outcomes of elderly patients receiving broad- versus narrow-spectrum antibiotics during hospitalization for AECOPD. DESIGN: A multicenter, retrospective, cohort analysis was performed. Inpatients 65 years and older with a primary discharge diagnosis of AECOPD who received ≥48 hours of antibiotic therapy were included in the study population. Patients were compared based on the spectrum of their antibiotic therapy. Narrow-spectrum antibiotics included: azithromycin, doxycycline, sulfamethoxazole/trimethoprim, or aminopenicillin. The primary outcome was a composite of mechanical ventilation 48 hours after admission, transfer to the intensive care unit 48 hours after admission, 30-day chronic obstructive pulmonary disease (COPD) readmission, and oxygen saturation less than 90% on room air or increased oxygen requirements from baseline 48 hours after admission. RESULTS: Two hundred fifty-three patients were included in this analysis; 127 patients were included in the narrow-spectrum group, and 126 patients were included in the broad-spectrum group. Patient demographics and comorbid conditions were similarly distributed in each group. The incidence of the primary composite outcome occurred in 50 (39.3%) and 60 (47.6%) of patients in the narrow- and broad-spectrum groups, respectively (P = .19). CONCLUSIONS AND RELEVANCE: No difference was found in the primary outcome in inpatients aged ≥65 years with AECOPD who received empiric broad-spectrum or narrow-spectrum antibiotics.


Assuntos
Antibacterianos , Doença Pulmonar Obstrutiva Crônica , Doença Aguda , Idoso , Antibacterianos/uso terapêutico , Progressão da Doença , Hospitalização , Humanos , Penicilinas , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Estudos Retrospectivos
3.
Front Vet Sci ; 8: 768709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869738

RESUMO

Since magnetic resonance imaging (MRI) was introduced, it has become increasingly available and technologically improved. Studies have documented the prevalence of specific pathologies, however no previous veterinary studies have investigated the prevalence and distribution of pathology across all MRIs performed at a single institution. The present study aimed to evaluate the prevalence of MRI-diagnosed brain lesions and correlate these to patient signalment and presenting complaint. Archived MRI brain scans from 805 dogs were reviewed retrospectively. One board-certified veterinary radiologist at the institution retrospectively evaluated all reports to determine the most clinically pertinent imaging diagnosis for each case. Breed, age, and presenting complaint were obtained from the medical record for each patient. The most common imaging diagnoses across all dogs reviewed were no significant findings (35.16%), asymmetric encephalopathy or meningoencephalopathy (19.75%), and extra-axial intracranial mass (11.18%). Age of dogs differed by diagnosis (p <0.0001), with the median age of dogs diagnosed with a brain mass being greater than that of dogs with no significant findings and dogs with asymmetric encephalopathy or meningoencephalopathy (both p <0.0083). In dogs presenting with seizures, the odds of a brain mass increased with each additional year of age [p <0.0001, odds ratio 1.26 (95% CI 1.16-1.37)], whereas the odds of no significant finding [p <0.0001, OR 0.87 (0.82-0.93)] decreased. Our findings provide overview information on the types of disease observed in the clinical population and allow us to detect correlations between imaging diagnoses, presenting complaints, and signalment.

4.
Brain Behav ; 11(5): e02005, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33662187

RESUMO

INTRODUCTION: Understanding the emotional responsivity style and neurocognitive profiles of depression-related processes in at-risk youth may be helpful in revealing those most likely to develop affective disorders. However, the multiplicity of biopsychosocial risk factors makes it difficult to disentangle unique and combined effects at a neurobiological level. METHODS: In a population-derived sample of 56 older adolescents (aged 17-20), we adopted partial least squares regression and correlation models to explore the relationships between multivariate biopsychosocial risks for later depression, emotional response style, and fMRI activity, to rejecting and inclusive social feedback. RESULTS: Behaviorally, higher depressive risk was associated with both reduced negative affect following negative social feedback and reduced positive affect following positive social feedback. In response to both cues of rejection and inclusion, we observed a general neural pattern of increased cingulate, temporal, and striatal activity in the brain. Secondly, in response to rejection only, we observed a pattern of activity in ostensibly executive control- and emotion regulation-related brain regions encompassing fronto-parietal brain networks including the angular gyrus. CONCLUSION: The results suggest that risk for depression is associated with a pervasive emotional insensitivity in the face of positive and negative social feedback.


Assuntos
Regulação Emocional , Emoções , Adolescente , Atenção , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
5.
Cerebellum Ataxias ; 8(1): 1, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397502

RESUMO

BACKGROUND: Transcranial Direct Current Stimulation (tDCS) over the prefrontal cortex has been shown to modulate subjective, neuronal and neuroendocrine responses, particularly in the context of stress processing. However, it is currently unknown whether tDCS stimulation over other brain regions, such as the cerebellum, can similarly affect the stress response. Despite increasing evidence linking the cerebellum to stress-related processing, no studies have investigated the hormonal and behavioural effects of cerebellar tDCS. METHODS: This study tested the hypothesis of a cerebellar tDCS effect on mood, behaviour and cortisol. To do this we employed a single-blind, sham-controlled design to measure performance on a cerebellar-dependent saccadic adaptation task, together with changes in cortisol output and mood, during online anodal and cathodal stimulation. Forty-five participants were included in the analysis. Stimulation groups were matched on demographic variables, potential confounding factors known to affect cortisol levels, mood and a number of personality characteristics. RESULTS: Results showed that tDCS polarity did not affect cortisol levels or subjective mood, but did affect behaviour. Participants receiving anodal stimulation showed an 8.4% increase in saccadic adaptation, which was significantly larger compared to the cathodal group (1.6%). CONCLUSION: The stimulation effect on saccadic adaptation contributes to the current body of literature examining the mechanisms of cerebellar stimulation on associated function. We conclude that further studies are needed to understand whether and how cerebellar tDCS may module stress reactivity under challenge conditions.

6.
J Am Vet Med Assoc ; 257(7): 697-700, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32955389

Assuntos
Animais
7.
Dev Psychopathol ; 32(2): 411-423, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-30895920

RESUMO

Childhood adversity (CA) increases the risk of subsequent mental health problems. Adolescent social support (from family and/or friends) reduces the risk of mental health problems after CA. However, the mechanisms of this effect remain unclear, and we speculate that they are manifested on neurodevelopmental levels. Therefore, we investigated whether family and/or friendship support at ages 14 and 17 function as intermediate variables for the relationship between CA before age 11 and affective or neural responses to social rejection feedback at age 18. We studied 55 adolescents with normative mental health at age 18 (26 with CA and therefore considered "resilient"), from a longitudinal cohort. Participants underwent a Social Feedback Task in the magnetic resonance imaging scanner. Social rejection feedback activated the dorsal anterior cingulate cortex and the left anterior insula. CA did not predict affective or neural responses to social rejection at age 18. Yet, CA predicted better friendships at age 14 and age 18, when adolescents with and without CA had comparable mood levels. Thus, adolescents with CA and normative mood levels have more adolescent friendship support and seem to have normal mood and neural responses to social rejection.


Assuntos
Imageamento por Ressonância Magnética , Distância Psicológica , Adolescente , Afeto , Criança , Amigos , Giro do Cíngulo , Humanos
8.
Vet Surg ; 48(6): 1013-1018, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31056780

RESUMO

OBJECTIVE: To measure the density of cellular phenotypes in canine caudal cruciate ligament (CaCL), cranial cruciate ligament (CrCL), medial collateral ligament (MCL), and long digital extensor tendon (LDET). STUDY DESIGN: Ex-vivo study. METHODS: Ten CaCL, CrCL, MCL, and LDET obtained from 1 stifle of 10 dogs with no gross pathology were analyzed histologically. The density of cells with 3 nuclear phenotypes (fusiform, ovoid, and spheroid) was determined within the core region of each specimen. RESULTS: Cells with fusiform nuclei were most dense in the MCL (median [range], 319 [118-538] cells/mm2 ) and LDET (331 [61-463]), whereas cells with ovoid nuclei were most dense in the CaCL (276 [123-368]) and CrCL (212 [165-420]). The spheroid nuclear phenotype had the lowest density in all structures (31 [5-61] in CaCL, 54 [5-90] in CrCL, 2 [0-14] in MCL, and 5 [0-80] in LDET); however, the CrCL contained a denser population of spheroid cells compared with MCL and LDET (P < .05). Total cell densities did not differ among the 4 structures (P > .05). CONCLUSION: Phenotype density varied within the ligaments and tendon tested here. The cell population of CaCL and CrCL differed from that of dense collagenous tissues such as MCL and LDET. CLINICAL SIGNIFICANCE: The relatively higher density of spheroid phenotype in CrCL may reflect a distinctive native cellular population or a cellular transformation secondary to unique mechanical environment or hypoxia. This intrinsic cellular population may explain altered tissue properties prone to pathological rupture or poor healing potential of the canine CrCL.


Assuntos
Ligamento Cruzado Anterior/citologia , Cães/anatomia & histologia , Joelho de Quadrúpedes/anatomia & histologia , Tendões/citologia , Animais , Lesões do Ligamento Cruzado Anterior/veterinária , Fenômenos Biomecânicos , Fenótipo , Ruptura/veterinária , Joelho de Quadrúpedes/fisiologia , Tíbia
9.
Psychoneuroendocrinology ; 92: 41-49, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29625374

RESUMO

Despite being overlooked in theoretical models of stress-related disorders, differences in cerebellar structure and function are consistently reported in studies of individuals exposed to current and early-life stressors. However, the mediating processes through which stress impacts upon cerebellar function are currently unknown. The aim of the current experiment was to test the effects of experimentally-induced acute stress on cerebellar functioning, using a classic, forward saccadic adaptation paradigm in healthy, young men and women. Stress induction was achieved by employing the Montreal Imaging Stress Task (MIST), a task employing mental arithmetic and negative social feedback to generate significant physiological and endocrine stress responses. Saccadic adaptation was elicited using the double-step target paradigm. In the experiment, 48 participants matched for gender and age were exposed to either a stress (n = 25) or a control (n = 23) condition. Saliva for cortisol analysis was collected before, immediately after, and 10, and 30 min after the MIST. Saccadic adaptation was assessed approximately 10 min after stress induction, when cortisol levels peaked. Participants in the stress group reported significantly more stress symptoms and exhibited greater total cortisol output compared to controls. The stress manipulation was associated with slower learning rates in the stress group, while control participants acquired adaptation faster. Learning rates were negatively associated with cortisol output and mood disturbance. Results suggest that experimentally-induced stress slowed acquisition of cerebellar-dependent saccadic adaptation, related to increases in cortisol output. These 'proof-of-principle' data demonstrate that stress modulates cerebellar-related functions.


Assuntos
Cerebelo/fisiologia , Estresse Psicológico/fisiopatologia , Adaptação Fisiológica/fisiologia , Adulto , Índice de Massa Corporal , Cognição , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Hidrocortisona/análise , Aprendizagem/fisiologia , Masculino , Psicologia/métodos , Movimentos Sacádicos , Saliva/química , Córtex Sensório-Motor/fisiologia , Estresse Psicológico/metabolismo , Adulto Jovem
10.
Sci Rep ; 7: 42010, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28169323

RESUMO

Social interaction inherently involves the subjective evaluation of cues salient to social inclusion and exclusion. Testifying to the importance of such social cues, parts of the neural system dedicated to the detection of physical pain, the dorsal anterior cingulate cortex (dACC) and anterior insula (AI), have been shown to be equally sensitive to the detection of social pain experienced after social exclusion. However, recent work suggests that this dACC-AI matrix may index any socially pertinent information. We directly tested the hypothesis that the dACC-AI would respond to cues of both inclusion and exclusion, using a novel social feedback fMRI paradigm in a population-derived sample of adolescents. We show that the dACC and left AI are commonly activated by feedback cues of inclusion and exclusion. Our findings suggest that theoretical accounts of the dACC-AI network as a neural alarm system restricted within the social domain to the processing of signals of exclusion require significant revision.


Assuntos
Encéfalo/fisiopatologia , Vias Neurais , Dor/fisiopatologia , Distância Psicológica , Meio Social , Estresse Psicológico , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
11.
Soc Cogn Affect Neurosci ; 11(2): 272-81, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26341903

RESUMO

Individuals exposed to childhood adversities (CA) present with emotion regulation (ER) difficulties in later life, which have been identified as risk and maintenance factors for psychopathologies. However, it is unclear if CA negatively impacts on ER capacity per se or whether observed regulation difficulties are a function of the challenging circumstances in which ER is being deployed. In this longitudinal study, we aimed to clarify this association by investigating the behavioral and neural effects of exposure to common moderate CA (mCA) on a laboratory measure of ER capacity in late adolescence/young adulthood. Our population-derived samples of adolescents/young adults (N = 53) were administered a film-based ER-task during functional magnetic resonance imaging that allowed evaluation of ER across mCA-exposure. mCA-exposure was associated with enhanced ER capacity over both positive and negative affect. At the neural level, the better ER of negative material in those exposed to mCA was associated with reduced recruitment of ER-related brain regions, including the prefrontal cortex and temporal gyrus. In addition mCA-exposure was associated with a greater down-regulation of the amygdala during ER of negative material. The implications of these findings for our understanding of the effects of mCA on the emergence of resilience in adolescence are discussed.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Encéfalo/fisiologia , Emoções/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
12.
BJPsych Bull ; 39(6): 305-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26755992

RESUMO

Treatment resistance occurs in approximately 30% of individuals with schizophrenia and is commonly treated with clozapine. Nodular sclerosing Hodgkin's lymphoma is a subtype of Hodgkin's lymphoma predominantly affecting those under 50 years of age. In this case report, an individual with treatment-resistant schizophrenia developed nodular sclerosing Hodgkin's lymphoma and is treated with concurrent clozapine and systemic chemotherapy. The aim of this case report is to act as guidance for clinicians and to outline the difficulties of treating individuals with psychiatric illness under the Mental Capacity Act 2005 when the proposed treatment could lead to high levels of morbidity and mortality.

13.
Neuroimage Clin ; 4: 308-18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25061568

RESUMO

Exposure to childhood adversities (CA) is associated with subsequent alterations in regional brain grey matter volume (GMV). Prior studies have focused mainly on severe neglect and maltreatment. The aim of this study was to determine in currently healthy adolescents if exposure to more common forms of CA results in reduced GMV. Effects on brain structure were investigated using voxel-based morphometry in a cross-sectional study of youth recruited from a population-based longitudinal cohort. 58 participants (mean age = 18.4) with (n = 27) or without (n = 31) CA exposure measured retrospectively from maternal interview were included in the study. Measures of recent negative life events (RNLE) recorded at 14 and 17 years, current depressive symptoms, gender, participant/parental psychiatric history, current family functioning perception and 5-HTTLPR genotype were covariates in analyses. A multivariate analysis of adversities demonstrated a general association with a widespread distributed neural network consisting of cortical midline, lateral frontal, temporal, limbic, and cerebellar regions. Univariate analyses showed more specific associations between adversity measures and regional GMV: CA specifically demonstrated reduced vermis GMV and past psychiatric history with reduced medial temporal lobe volume. In contrast RNLE aged 14 was associated with increased lateral cerebellar and anterior cingulate GMV. We conclude that exposure to moderate levels of childhood adversities occurring during childhood and early adolescence exerts effects on the developing adolescent brain. Reducing exposure to adverse social environments during early life may optimize typical brain development and reduce subsequent mental health risks in adult life.


Assuntos
Encéfalo/patologia , Substância Cinzenta/patologia , Imageamento Tridimensional/métodos , Acontecimentos que Mudam a Vida , Imageamento por Ressonância Magnética/métodos , Carência Psicossocial , Adolescente , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Tamanho do Órgão , Psicologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Am Acad Child Adolesc Psychiatry ; 53(6): 677-687.e5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24839886

RESUMO

OBJECTIVE: Conduct disorder (CD) in females is associated with negative adult outcomes including mental health problems and personality disorders. Although recent neuroimaging studies have reported changes in neural activity during facial emotion processing in males with CD or callous-unemotional (CU) traits, there have been no neuroimaging studies specifically assessing females with CD. We addressed this gap by investigating whether female adolescents with CD show atypical neural activation when processing emotional or neutral faces. METHOD: We acquired functional magnetic resonance imaging (fMRI) data from 20 female adolescents with CD and 20 female control participants while they viewed angry, sad, and neutral faces. RESULTS: An omnibus group (CD, control) by facial emotion (angry, sad, neutral) analysis of variance (ANOVA) revealed main effects of facial emotion in superior temporal cortex, fusiform gyrus, ventrolateral prefrontal cortex and insula, and main effects of group in medial orbitofrontal cortex (OFC) and right anterior insula. Female participants with CD showed reduced medial OFC and increased anterior insula responses relative to healthy controls. There were no significant group × facial emotion interactions. Lifetime CD symptoms were negatively correlated with amygdala, superior temporal cortex, fusiform gyrus, and dorsolateral prefrontal cortex activity for the contrast "all-faces versus fixation." CU traits were negatively correlated with fusiform gyrus activity for the contrast sad versus neutral faces. CONCLUSION: Females with CD showed atypical neural activation during the processing of all facial expressions, irrespective of valence. Our results demonstrate that severity of CD symptoms and CU traits is important in explaining abnormal patterns of neural activity.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Transtorno da Conduta/fisiopatologia , Emoções/fisiologia , Expressão Facial , Adolescente , Feminino , Humanos , Imageamento por Ressonância Magnética
15.
J Affect Disord ; 151(2): 423-431, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23890584

RESUMO

BACKGROUND: Major Depressive Disorder (MDD) is a leading cause of disease burden worldwide. With the rapid growth of neuroimaging research on relatively small samples, meta-analytic techniques are becoming increasingly important. Here, we aim to clarify the support in fMRI literature for three leading neurobiological models of MDD: limbic-cortical, cortico-striatal and the default mode network. METHODS: Searches of PubMed and Web of Knowledge, and manual searches, were undertaken in early 2011. Data from 34 case-control comparisons (n=1165) and 6 treatment studies (n=105) were analysed separately with two meta-analytic methods for imaging data: Activation Likelihood Estimation and Gaussian-Process Regression. RESULTS: There was broad support for limbic-cortical and cortico-striatal models in the case-control data. Evidence for the role of the default mode network was weaker. Treatment-sensitive regions were primarily in lateral frontal areas. LIMITATIONS: In any meta-analysis, the increase in the statistical power of the inference comes with the risk of aggregating heterogeneous study pools. While we believe that this wide range of paradigms allows identification of key regions of dysfunction in MDD (regardless of task), we attempted to minimise such risks by employing GPR, which models such heterogeneity. CONCLUSIONS: The focus of treatment effects in frontal areas indicates that dysregulation here may represent a biomarker of treatment response. Since the dysregulation in many subcortical regions in the case-control comparisons appeared insensitive to treatment, we propose that these act as trait vulnerability markers, or perhaps treatment insensitivity. Our findings allow these models of MDD to be applied to fMRI literature with some confidence.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/fisiopatologia , Imageamento por Ressonância Magnética , Córtex Cerebral/fisiopatologia , Humanos , Sistema Límbico/fisiopatologia , Masculino , Modelos Biológicos , Córtex Visual/fisiopatologia
16.
J Child Psychol Psychiatry ; 54(1): 86-95, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23082797

RESUMO

BACKGROUND: Conduct disorder (CD) in female adolescents is associated with a range of negative outcomes, including teenage pregnancy and antisocial personality disorder. Although recent studies have documented changes in brain structure and function in male adolescents with CD, there have been no neuroimaging studies of female adolescents with CD. Our primary objective was to investigate whether female adolescents with CD show changes in grey matter volume. Our secondary aim was to assess for sex differences in the relationship between CD and brain structure. METHODS: Female adolescents with CD (n = 22) and healthy control participants matched in age, performance IQ and handedness (n = 20) underwent structural magnetic resonance imaging. Group comparisons of grey matter volume were performed using voxel-based morphometry. We also tested for sex differences using archive data obtained from male CD and control participants. RESULTS: Female adolescents with CD showed reduced bilateral anterior insula and right striatal grey matter volumes compared with healthy controls. Aggressive CD symptoms were negatively correlated with right dorsolateral prefrontal cortex volume, whereas callous-unemotional traits were positively correlated with bilateral orbitofrontal cortex volume. The sex differences analyses revealed a main effect of diagnosis on right amygdala volume (reflecting reduced amygdala volume in the combined CD group relative to controls) and sex-by-diagnosis interactions in bilateral anterior insula. CONCLUSIONS: We observed structural abnormalities in brain regions involved in emotion processing, reward and empathy in female adolescents with CD, which broadly overlap with those reported in previous studies of CD in male adolescents.


Assuntos
Encéfalo/patologia , Transtorno da Conduta/patologia , Caracteres Sexuais , Adolescente , Agressão , Tonsila do Cerebelo/patologia , Estudos de Casos e Controles , Córtex Cerebral/patologia , Empatia , Feminino , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/patologia , Recompensa , Adulto Jovem
17.
PLoS One ; 7(11): e48482, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209555

RESUMO

BACKGROUND: Polymorphisms in the promoter region of the serotonin transporter gene (5-HTTLPR) and exposure to early childhood adversities (CA) are independently associated with individual differences in cognitive and emotional processing. Whether these two factors interact to influence cognitive and emotional processing is not known. METHODOLOGY AND PRINCIPAL FINDINGS: We used a sample of 238 adolescents from a community study characterised by the presence of the short allele of 5-HTTLPR (LL, LS, SS) and the presence or absence of exposure to CA before 6 years of age. We measured cognitive and emotional processing using a set of neuropsychological tasks selected predominantly from the CANTAB® battery. We found that adolescents homozygous for the short allele (SS) of 5-HTTLPR and exposed to CA were worse at classifying negative and neutral stimuli and made more errors in response to ambiguous negative feedback. In addition, cognitive and emotional processing deficits were associated with diagnoses of anxiety and/or depressions. CONCLUSION AND SIGNIFICANCE: Cognitive and emotional processing deficits may act as a transdiagnostic intermediate marker for anxiety and depressive disorders in genetically susceptible individuals exposed to CA.


Assuntos
Cognição/fisiologia , Emoções/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adolescente , Alelos , Ansiedade/genética , Depressão/genética , Feminino , Interação Gene-Ambiente , Genótipo , Humanos , Masculino , Polimorfismo Genético , Regiões Promotoras Genéticas
18.
Neuroimage ; 63(3): 1670-80, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23034517

RESUMO

It is not known how 5-HTTLPR genotype x childhood adversity (CA) interactions that are associated with an increased risk for affective disorders in population studies operate at the neural systems level. We hypothesized that healthy adolescents at increased genetic and environmental risk for developing mood disorders (depression and anxiety) would demonstrate increased amygdala reactivity to emotional stimuli compared to those with only one such risk factor or those with none. Participants (n=67) were classified into one of 4 groups dependent on being homozygous for the long or short alleles within the serotonin-transporter-linked polymorphic region (5-HTTLPR) of the SLC6A4 gene and exposure to CA in the first 11 years of life (present or absent). A functional magnetic resonance imaging investigation was undertaken which involved viewing emotionally-salient face stimuli. In addition, we assessed the role of other variables hypothesized to influence amygdala reactivity, namely recent negative life-events (RNLE) assessed at ages 14 and 17, current anxiety symptoms and psychiatric history. We replicated prior findings demonstrating moderation by gene variants in 5-HTTLPR, but found no support for an effect of CA on amygdala reactivity. We also found a significant effect of RNLE aged 17 with amygdala reactivity demonstrating additive, but not interactive effects with 5-HTTLPR. A whole-brain analysis found a 5-HTTLPR×CA interaction in the lingual gyrus whereby CA appears to differentially modify neural reactivity depending on genotype. These results demonstrate that two different forms of environmental adversities interplay with 5-HTTLPR and thereby differentially impact amygdala and cortical reactivity.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Interação Gene-Ambiente , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Estresse Psicológico/complicações , Adolescente , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Estresse Psicológico/genética
19.
J Affect Disord ; 126(1-2): 272-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20392498

RESUMO

BACKGROUND: Hippocampal atrophy is a well reported feature of major depressive disorder, although the evidence has been mixed. The present study sought to examine hippocampal volume and subregional morphology in patients with major depressive disorder, who were all medication-free and in an acute depressive episode of moderate severity. METHODS: Structural magnetic resonance imaging scans were acquired in 37 patients (mean age 42 years) and 37 age, gender and IQ-matched healthy individuals. Hippocampal volume and subregional structural differences were measured by manual tracings and identification of homologous surface points to the central core of each hippocampus. RESULTS: Both right (P=0.001) and left (P=0.005) hippocampal volumes were reduced in patients relative to healthy controls (n=37 patients and n=37 controls), while only the right hippocampus (P=0.016) showed a reduced volume in a subgroup of first-episode depression patients (n=13) relative to healthy controls. Shape analysis localised the subregional deformations to the subiculum and CA1 subfield extending into the CA2-3 subfields predominantly in the tail regions in the right (P=0.017) and left (P=0.011) hippocampi. LIMITATIONS: As all patients were in an acute depressive episode, effects associated with depressive state cannot be distinguished from trait effects. CONCLUSIONS: Subregional hippocampal deficits are present early in the course of major depression. The deformations may reflect structural correlates underlying functional memory impairments and distinguish depression from other psychiatric disorders.


Assuntos
Transtorno Depressivo Maior/patologia , Hipocampo/patologia , Adulto , Estudos de Casos e Controles , Transtorno Depressivo Maior/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão
20.
Cereb Cortex ; 20(2): 271-81, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19429861

RESUMO

Cognitive control is an inherently multivariate phenomenon, and its neural basis is currently unclear. Here we examined using functional magnetic resonance imaging how participants retrieve prelearnt information from memory, use this information to guide responses for an impending decision, and adjust their responses based on outcome feedback. We developed a behavioral task designed to manipulate memory outcome-retrieval load, outcome-anticipation interval, and outcome-feedback processes. This allowed us to understand the neural basis of these cognitive processes in isolation and how they interact. Extending previous work, we found a retrieval-load by outcome-feedback interaction in the left globus pallidus; an outcome-feedback by anticipation-interval interaction in the inferior prefrontal cortex; a retrieval-load by anticipation-interval interaction in the midcingulate gyrus and a load by interval by outcome interaction in the right frontal pole. These results further advance our knowledge of how fundamental cognitive processes interact physiologically to give rise to higher-level behavioral control.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Cognição/fisiologia , Retroalimentação Psicológica/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Adulto , Mapeamento Encefálico , Função Executiva/fisiologia , Feminino , Globo Pálido/anatomia & histologia , Globo Pálido/fisiologia , Giro do Cíngulo/anatomia & histologia , Giro do Cíngulo/fisiologia , Humanos , Julgamento/fisiologia , Imageamento por Ressonância Magnética , Masculino , Motivação/fisiologia , Testes Neuropsicológicos , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
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