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2.
Behav Res Ther ; 183: 104639, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39368459

RESUMO

This study tested two versions of parent-led, Internet-delivered cognitive behavioral therapy for anxiety among autistic youth; one that provided weekly email support (iCBT-Email), and one that provided alternating bi-weekly emails and video calls (iCBT-Video) across 12 weeks. It was expected that those in the iCBT-Video condition would complete more treatment content, which in turn would lead to more anxiety improvement. Fifty-seven autistic youth (7-15 years-old) with anxiety disorders were randomized to iCBT-Email or iCBT-Video. There were no significant differences in improvement in clinician-rated, child-reported, or parent-reported anxiety severity or functional impairment. Posttreatment response rates were 55% in iCBT-Email and 67% in iCBT-Video. Module completion predicted improved treatment outcome, though there was no difference in module completion across groups. Therapists spent an average of 16.29 min/family/week (SD = 7.11) in the iCBT-Email condition and 24.13 min/family/week (SD = 6.84) in the iCBT-Video condition. Email and telehealth-supported, parent-led iCBT both appear to be effective treatments for autistic youth with anxiety disorders that require reduced therapist effort. Future research should seek novel methods to enhance engagement with iCBT content. CLINICALTRIALS.GOV IDENTIFIER: NCT05284435.

3.
J Affect Disord ; 362: 510-517, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39009313

RESUMO

BACKGROUND: Anxious depression is a prevalent subtype of depression associated with adverse outcomes such as higher depression severity and higher rates of suicidality. This study leveraged a state-wide research registry of depressed and/or suicidal youth to compare the prevalence, clinical correlates, and symptom patterns of those with versus without anxious depression. METHODS: We included baseline data from 797 participants (ages 8-20) with a diagnosis of a depressive disorder. A score on the Generalized Anxiety Disorder Scale (GAD-7) ≥ 10 was used to define individuals with and without anxious depression. A structured battery was used to capture psychiatric diagnostic status, depression/anxiety severity, suicide risk, history of trauma, functioning, and resilience. RESULTS: The prevalence of anxious depression among youth with depressive disorders was 59.5 % (n = 474). Youth with anxious depression had greater depression severity and anxiety symptoms, higher suicidality, and a higher prevalence of comorbid anxiety disorders than those without. Youth with anxious depression had greater impairment in functioning defined as worse pain interference, pain severity, fatigue, and social relationships compared to those without anxious depression. Youth with anxious depression also reported higher rates of depressive symptoms such as irritable mood, feelings of guilt, and psychomotor agitation compared to those without anxious depression. CONCLUSION: Anxious depression is associated with worse depression severity, higher suicidality, and lower functioning. Longitudinal work is needed to examine long-term courses of anxious depression to explore its stability as a diagnostic subcategory.


Assuntos
Transtornos de Ansiedade , Humanos , Adolescente , Feminino , Masculino , Criança , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/psicologia , Texas/epidemiologia , Adulto Jovem , Prevalência , Comorbidade , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Ansiedade/epidemiologia , Ansiedade/psicologia , Índice de Gravidade de Doença , Suicídio/estatística & dados numéricos , Suicídio/psicologia , Depressão/epidemiologia , Depressão/psicologia , Ideação Suicida , Escalas de Graduação Psiquiátrica
4.
J Psychiatr Res ; 170: 237-244, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169247

RESUMO

There is a tremendous need for brief, valid, and free assessments of anxiety in child mental healthcare. The goal of this study was to determine the psychometric properties of two such measures, the GAD-7 and PROMIS-Anxiety-4a, in 1000 children, adolescents, and young adults (8-20 years-old) with depression and/or suicidality. The GAD-7, the PROMIS-Anxiety-4a, and other validated assessments of anxiety, physical functioning, and psychiatric diagnoses were completed. Confirmatory factor analyses showed an acceptable fit for a single factor in both measures via all indices but the RMSEA. They demonstrated measurement invariance across pre-adolescents (8-12 years-old) and adolescents and emerging adults (13-20 years-old), though scalar invariance was not observed for the GAD-7. Both measures showed strong convergent validity, GAD-7: r = 0.68; PROMIS-Anxiety-4a: r = 0.75, divergent validity with a measure of physical function, GAD-7: r = -0.24; PROMIS-Anxiety-4a: r = -0.28, good internal consistency, ω = 0.89 for both, and high test-retest reliability, GAD-7: r = 0.69; PROMIS-Anxiety-4a: r = 0.71. Both measures also showed acceptable sensitivity and specificity in detecting the presence of any anxiety disorder, GAD-7 cut-off score of 10: AUC = 0.75; PROMIS-Anxiety-4a cutoff score of 12: AUC = 0.79. The GAD-7 correlated similarly with the Screen for Child Anxiety Related Disorders total score and generalized anxiety subscale, and also showed similar diagnostic sensitivity and specificity when used to detect the presence of any anxiety disorder vs. generalized anxiety disorder specifically. Results suggest that both of these brief, publicly available instruments are valid and reliable assessments of anxiety among youth in treatment for depression and/or suicidality.


Assuntos
Depressão , Suicídio , Adulto Jovem , Criança , Humanos , Adolescente , Adulto , Depressão/diagnóstico , Questionário de Saúde do Paciente , Texas , Psicometria/métodos , Reprodutibilidade dos Testes , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Ansiedade/diagnóstico
5.
J Affect Disord ; 349: 349-357, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199393

RESUMO

BACKGROUND: Major depressive disorder (MDD) is common in youth and among the most frequent comorbid disorders in pediatric obsessive-compulsive disorder (OCD), but it is unclear whether the presence of OCD affects the symptom presentation of MDD in youth. METHODS: A sample of youth with OCD and MDD (n = 124) and a sample of youth with MDD but no OCD (n = 673) completed the Patient Health Questionnaire for Adolescents (PHQ-A). The overall and symptom-level presentation of MDD were examined using group comparisons and network analysis. RESULTS: Youth with MDD and OCD, compared to those with MDD and no OCD, had more severe MDD (Cohen's d = 0.39) and more reported moderate to severe depression (75 % vs 61 %). When accounting for demographic variables and the overall severity of MDD, those with comorbid OCD reported lower levels of anhedonia and more severe difficulties with psychomotor retardation/agitation. No significant differences in the interconnections among symptoms emerged. LIMITATIONS: Data were cross-sectional and self-reported, gold standard diagnostic tools were not used to assess OCD, and the sample size for the group with MDD and OCD was relatively small yielding low statistical power for network analysis. CONCLUSIONS: Youth with MDD and OCD have more severe MDD than those with MDD and no OCD and they experience more psychomotor issues and less anhedonia, which may relate to the behavioral activation characteristic of OCD.


Assuntos
Transtorno Depressivo Maior , Transtorno Obsessivo-Compulsivo , Humanos , Adolescente , Criança , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Anedonia , Comorbidade , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtornos de Ansiedade/epidemiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-37521713

RESUMO

Obsessive-compulsive disorder (OCD), anxiety disorders, and depressive disorders are highly comorbid, and each contribute to significant functional impairment for affected youth. Comorbid anxiety disorders in depressed youth have been associated with greater depressive symptom severity and impairment, but the impact of comorbid OCD in this population remains unclear. Accordingly, the present study examined the differential clinical characteristics of youth with depression and comorbid OCD relative to age/gender matched depressed youth with no such comorbidity and to those with depression and a comorbid (non-OCD) anxiety disorder. A sample of 797 youth and young adults ages 8-20 years who met diagnostic criteria for depression alone, depression with co-occurring OCD or any anxiety disorder were included in the present study. Rates of comorbid anxiety and OCD were very high (60.5% and 15.5%, respectively). Relative to youth with only depression, depressed youth with comorbid OCD or anxiety had greater severity of depression, suicidality, and overall impairment in social, physical, and emotional functioning. These results highlight the contribution of OCD or anxiety comorbidity in more complex clinical presentations for depressed youth.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36908861

RESUMO

Cognitive behavioral therapy adapted for autistic youth with anxiety and/or OCD has a strong evidence base, but few have access. A 12-week family-based, Internet-delivered cognitive behavioral therapy (iCBT) program for 7-15 year-old autistic youth with anxiety and/or OCD was developed as a potential method to address this problem. Quantitative and qualitative feedback from stakeholders (parents, youth, clinicians) was gathered on an initial draft of content before conducting a pilot trial. This feedback suggested high quality, engagement, usability, and informativeness of the material. Suggestions were incorporated into the treatment program that was tested in a pilot trial. Eight families were randomized to the iCBT program with either 1) weekly email support or 2) weekly email support plus biweekly telehealth check-ins, and seven of these families completed pre- and post-treatment assessments. An average reduction of 39% in anxiety severity was found, with six of the seven being classified as responders. Preliminary evidence suggests that family-based iCBT is an acceptable and promising treatment for autistic youth with anxiety and/or obsessive-compulsive disorders that should be further modified and tested in future work.

8.
J Psychiatr Res ; 161: 179-187, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36933444

RESUMO

Symptoms of irritability, anxiety, panic, and insomnia are common in patients with depression, and their worsening after antidepressant treatment initiation is associated with poorer long-term outcomes. The Concise Associated Symptom Tracking (CAST) scale was developed to measure these symptoms in adults with major depressive disorder (MDD). Here, we evaluate the psychometric properties of CAST in an ongoing community-based observational study involving children, adolescents, and young adults. Individuals from the ongoing Texas Youth Depression and Suicide Research Network (TX-YDSRN; N = 952) with CAST data available were included. Fit statistics [Goodness of Fit Index (GFI), Comparative Fit Index (CFI), and Root Mean Square Error of Approximation (RMSEA)] from confirmatory factor analyses were used to evaluate the five- and four-domain structure of CAST. Item response theory (IRT) analyses were also used. Individuals were grouped based on age (in years) as youths (8-17) and young adults (18-20). Correlations with other clinical measures were used to inform construct validity. Four-domain (irritability, anxiety, panic, and insomnia) 12-item structure of CAST (CAST-12) was optimal for youths (N = 709, GFI = 0.906, CFI = 0.919, RMSEA = 0.095) and young adults (N = 243, GFI = 0.921, CFI = 0.938, RMSEA = 0.0797) with Cronbach's alpha of 0.87 and 0.88, respectively. Slope of each item exceeded 1.0 on IRT analyses suggesting adequate discrimination for each item. Scores on irritability, anxiety, panic, and insomnia were significantly correlated with similar items on other scales. Together these findings suggest that CAST-12 is a valid self-report measure of irritability, anxiety, insomnia, and panic in youths and young adults.


Assuntos
Transtorno Depressivo Maior , Distúrbios do Início e da Manutenção do Sono , Suicídio , Criança , Humanos , Adolescente , Adulto Jovem , Depressão/diagnóstico , Transtorno Depressivo Maior/tratamento farmacológico , Psicometria , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Texas/epidemiologia , Reprodutibilidade dos Testes , Inquéritos e Questionários , Análise Fatorial
9.
MSMR ; 28(6): 2-5, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34379377

RESUMO

The first U.S. case of non-travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was detected in late February 2020 in California, but the prevailing delay in diagnostic testing and initial stringent testing criteria made it difficult to identify those who could have acquired the virus through community spread. The emergence of the virus in the western Pacific region in late 2019 and the global distribution of Department of Defense (DoD) personnel present the risk that DoD members may have been exposed and contracted the virus earlier then U.S. detections. Here, a retrospective study from residual samples collected from a global DoD Respiratory Surveillance Program was conducted to establish a tentative timeline of when this virus began circulating in the DoD population. Quantitative real-time reverse-transcription polymerase chain reaction testing for SARS-CoV-2 was performed and the specimen collection dates of positive results were compared to the dates of the first infections previously identified in respective states and counties. Twenty-four positive samples were identified out of approximately 7,000 tested. Although this retrospective testing found early cases in 8 locations, there were no results indicative of circulation before late February.


Assuntos
Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , COVID-19/epidemiologia , Militares/estatística & dados numéricos , Vigilância da População , SARS-CoV-2 , Adulto , COVID-19/diagnóstico , Teste de Ácido Nucleico para COVID-19/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia , Adulto Jovem
10.
Med Sci Educ ; 31(1): 15-16, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34457856

RESUMO

A case-based laboratory event integrating neuroanatomy, neuroscience, and psychiatry was implemented into a pre-clerkship psychiatry-based course for second-year medical students. Learners rotating through lab stations to work on different cases to make interdisciplinary connections among these fields is an innovative way for them to integrate foundational neurology, neuroanatomy, and psychiatry concepts. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40670-020-01171-0.

11.
J Sch Psychol ; 86: 198-221, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34051914

RESUMO

Rater-mediated assessments, such as teacher behavior rating scales, measure student behavior indirectly through the lens of a rater. As a result, scores from rater-mediated assessments can be influenced by rater effects- individual differences in rater perspectives, attitudes, beliefs, and interpretation of rating scale items. Rater effects are a fundamental aspect of all rater-mediated assessments. However, traditional approaches to evaluate rater effects (i.e., classical test theory, generalizability theory, and multilevel modeling) merely estimate how much score variability is due to the rater. These approaches, while informative, do not offer a solution to the problem. In contrast, Many-facet Rasch measurement (MFRM) approaches estimate and control for rater effects in rater-mediated assessments so that scores are adjusted to account for rater variability. Thus, MFRM offers unique insights into individual- and group-level rater effects that can be used to inform a solution. The resultant purpose of this paper is to introduce MFRM, discuss its advantages for evaluating rater effects in rater-mediated assessments, and demonstrate its use through an applied example.


Assuntos
Escala de Avaliação Comportamental , Pessoal de Educação , Humanos , Reprodutibilidade dos Testes
14.
Clin Cancer Res ; 24(6): 1426-1435, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29284706

RESUMO

Purpose: We describe herein a novel P447_L455 deletion in the C2 domain of PIK3CA in a patient with an ER+ breast cancer with an excellent response to the PI3Kα inhibitor alpelisib. Although PIK3CA deletions are relatively rare, a significant portion of deletions cluster within amino acids 446-460 of the C2 domain, suggesting these residues are critical for p110α function.Experimental Design: A computational structural model of PIK3CAdelP447-L455 in complex with the p85 regulatory subunit and MCF10A cells expressing PIK3CAdelP447-L455 and PIK3CAH450_P458del were used to understand the phenotype of C2 domain deletions.Results: Computational modeling revealed specific favorable inter-residue contacts that would be lost as a result of the deletion, predicting a significant decrease in binding energy. Coimmunoprecipitation experiments showed reduced binding of the C2 deletion mutants with p85 compared with wild-type p110α. The MCF10A cells expressing PIK3CA C2 deletions exhibited growth factor-independent growth, an invasive phenotype, and higher phosphorylation of AKT, ERK, and S6 compared with parental MCF10A cells. All these changes were ablated by alpelisib treatment.Conclusions: C2 domain deletions in PIK3CA generate PI3K dependence and should be considered biomarkers of sensitivity to PI3K inhibitors. Clin Cancer Res; 24(6); 1426-35. ©2017 AACR.

15.
Cancer Res ; 77(9): 2488-2499, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28249908

RESUMO

Acquired resistance to cyclin-dependent kinases 4 and 6 (CDK4/6) small-molecule inhibitors in breast cancer arises through mechanisms that are yet uncharacterized. In this study, we used a kinome-wide siRNA screen to identify kinases that, when downregulated, yield sensitivity to the CDK4/6 inhibitor ribociclib. In this manner, we identified 3-phosphoinositide-dependent protein kinase 1 (PDK1) as a key modifier of ribociclib sensitivity in estrogen receptor-positive MCF-7 breast cancer cells. Pharmacologic inhibition of PDK1 with GSK2334470 in combination with ribociclib or palbociclib, another CDK4/6 inhibitor, synergistically inhibited proliferation and increased apoptosis in a panel of ER-positive breast cancer cell lines. Ribociclib-resistant breast cancer cells selected by chronic drug exposure displayed a relative increase in the levels of PDK1 and activation of the AKT pathway. Analysis of these cells revealed that CDK4/6 inhibition failed to induce cell-cycle arrest or senescence. Mechanistic investigations showed that resistant cells coordinately upregulated expression of cyclins A, E, and D1, activated phospho-CDK2, and phospho-S477/T479 AKT. Treatment with GSK2334470 or the CDK2 inhibitor dinaciclib was sufficient to reverse these events and to restore the sensitivity of ribociclib-resistant cells to CDK4/6 inhibitors. Ribociclib, in combination with GSK2334470 or the PI3Kα inhibitor alpelisib, decreased xenograft tumor growth more potently than each drug alone. Taken together, our results highlight a role for the PI3K-PDK1 signaling pathway in mediating acquired resistance to CDK4/6 inhibitors. Cancer Res; 77(9); 2488-99. ©2017 AACR.


Assuntos
Aminopiridinas/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Serina-Treonina Quinases/genética , Purinas/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , Indazóis/administração & dosagem , Células MCF-7 , Camundongos , Fosfatidilinositol 3-Quinases/genética , Piperazinas/administração & dosagem , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/administração & dosagem , Pirimidinas/administração & dosagem , Piruvato Desidrogenase Quinase de Transferência de Acetil , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Neurochem ; 134(5): 833-44, 2015 09.
Artigo em Inglês | MEDLINE | ID: mdl-26011081

RESUMO

The nucleus accumbens is highly heterogeneous, integrating regionally distinct afferent projections and accumbal interneurons, resulting in diverse local microenvironments. Dopamine (DA) neuron terminals similarly express a heterogeneous collection of terminal receptors that modulate DA signaling. Cyclic voltammetry is often used to probe DA terminal dynamics in brain slice preparations; however, this method traditionally requires electrical stimulation to induce DA release. Electrical stimulation excites all of the neuronal processes in the stimulation field, potentially introducing simultaneous, multi-synaptic modulation of DA terminal release. We used optogenetics to selectively stimulate DA terminals and used voltammetry to compare DA responses from electrical and optical stimulation of the same area of tissue around a recording electrode. We found that with multiple pulse stimulation trains, optically stimulated DA release increasingly exceeded that of electrical stimulation. Furthermore, electrical stimulation produced inhibition of DA release across longer duration stimulations. The GABAB antagonist, CGP 55845, increased electrically stimulated DA release significantly more than light stimulated release. The nicotinic acetylcholine receptor antagonist, dihydro-ß-erythroidine hydrobromide, inhibited single pulse electrically stimulated DA release while having no effect on optically stimulated DA release. Our results demonstrate that electrical stimulation introduces local multi-synaptic modulation of DA release that is absent with optogenetically targeted stimulation.


Assuntos
Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Estimulação Elétrica , Núcleo Accumbens/citologia , Optogenética , Terminações Pré-Sinápticas/metabolismo , Acetilcolina/farmacologia , Animais , Artefatos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Channelrhodopsins , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/fisiologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Antagonistas de Receptores de GABA-B/farmacologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Técnicas de Introdução de Genes , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microeletrodos , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Núcleo Accumbens/metabolismo , Ácidos Fosfínicos/farmacologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Regiões Promotoras Genéticas , Propanolaminas/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/fisiologia , Tirosina 3-Mono-Oxigenase/genética , Área Tegmentar Ventral/metabolismo , Ácido gama-Aminobutírico/fisiologia
17.
Int J Radiat Biol ; 90(9): 799-806, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24991879

RESUMO

PURPOSE: To assess the long-term effects of fractionated whole brain irradiation (fWBI) using diffusion tensor imaging (DTI) and behavior in a pediatric rodent model for the clinical presentation of adult pediatric cancer survivors. MATERIALS AND METHODS: Five-week-old, male F344xBN rats were randomized to receive 0, 5, or 6.5 Gy fractions biweekly for 3 weeks, resulting in Sham, Irradiated-30 (IR-30) and IR-39 Gy total dose groups. Magnetic Resonance Imaging occurred at 1, 3, 6 and 9 months with behavioral assessment at 10-11 months post-fWBI. RESULTS: Irradiation reduced brain size (p < 0.001) and body weight (p < 0.001) proportionate to dose. At 1 month post-fWBI and throughout follow-up, diffusion was reduced in IR-30 and IR-39 relative to shams (p < 0.001). IR-30 but not IR-39 rats were impaired relative to Shams on the reversal trial of the Morris Water Maze (p < 0.05), and IR-30 rats preferred a striatum- mediated strategy (p < 0.06). CONCLUSIONS: Hippocampal performance was impaired in IR-30 but not IR-39 animals. While gross size differences exist, white matter integrity is preserved in rats after fWBI at 5 weeks. This significant departure from childhood cancer survivors and single fraction rodent studies where white matter degradation is a prominent feature are discussed.


Assuntos
Encéfalo/efeitos da radiação , Cognição/efeitos da radiação , Imagem de Tensor de Difusão , Fracionamento da Dose de Radiação , Radioterapia/métodos , Animais , Comportamento Animal/efeitos da radiação , Neoplasias Encefálicas/radioterapia , Hipocampo/efeitos da radiação , Imageamento por Ressonância Magnética , Masculino , Aprendizagem em Labirinto , Modelos Animais , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344
18.
Radiat Res ; 181(1): 33-44, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24397438

RESUMO

We hypothesized that dietary administration of the peroxisomal proliferator-activated receptor α agonist, fenofibrate, to young adult male rats would prevent the fractionated whole-brain irradiation (fWBI)-induced reduction in cognitive function and neurogenesis and prevent the fWBI-induced increase in the total number of activated microglia. Eighty 12-14-week-old young adult male Fischer 344 × Brown Norway rats received either: (1) sham irradiation, (2) 40 Gy of fWBI delivered as two 5 Gy fractions/week for 4 weeks, (3) sham irradiation + dietary fenofibrate (0.2% w/w) starting 7 days prior to irradiation, or (4) fWBI + fenofibrate. Cognitive function was measured 26-29 weeks after irradiation using: (1) the perirhinal cortex (PRh)-dependent novel object recognition task; (2) the hippocampal-dependent standard Morris water maze (MWM) task; (3) the hippocampal-dependent delayed match-to-place version of the MWM task; and (4) a cue strategy preference version of the MWM to distinguish hippocampal from striatal task performance. Neurogenesis was assessed 29 weeks after fWBI in the granular cell layer and subgranular zone of the dentate gyrus using a doublecortin antibody. Microglial activation was assessed using an ED1 antibody in the dentate gyrus and hilus of the hippocampus. A significant impairment in perirhinal cortex-dependent cognitive function was measured after fWBI. In contrast, fWBI failed to alter hippocampal-dependent cognitive function, despite a significant reduction in hippocampal neurogenesis. Continuous administration of fenofibrate prevented the fWBI-induced reduction in perirhinal cortex-dependent cognitive function, but did not prevent the radiation-induced reduction in neurogenesis or the radiation-induced increase in activated microglia. These data suggest that fenofibrate may be a promising therapeutic for the prevention of some modalities of radiation-induced cognitive impairment in brain cancer patients.


Assuntos
Cognição/efeitos dos fármacos , Cognição/efeitos da radiação , Fenofibrato/farmacologia , PPAR alfa/agonistas , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/efeitos da radiação , Peso Corporal/efeitos dos fármacos , Peso Corporal/efeitos da radiação , Proteína Duplacortina , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/efeitos da radiação , Ratos , Acuidade Visual/efeitos dos fármacos , Acuidade Visual/efeitos da radiação
19.
Biol Psychiatry ; 74(12): 890-7, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23607969

RESUMO

BACKGROUND: The anterior hippocampus is associated with emotional functioning and hippocampal volume is reduced in depression. More women are clinically depressed than men, yet the depressed female brain is little studied. We reported reduced anterior hippocampal volume in behaviorally depressed adult female cynomolgus macaques; the mechanisms contributing to that reduction are unknown. The present study represents the first systematic morphological investigation of the entire hippocampus in depressed female primates. METHODS: Cellular determinants of hippocampal size were examined in subregions of anterior and posterior hippocampus in antidepressant-naïve, adult female monkeys characterized for behavioral depression and matched on variables that influence hippocampal size (n = 8 depressed, 8 nondepressed). Unbiased stereology was used to estimate neuronal and glial numbers, neuronal soma size, and regional and layer volumes. RESULTS: Neuropil and cell layer volumes were reduced in cornu ammonis (CA)1 and dentate gyrus (DG) of the anterior but not the posterior hippocampus of depressed compared with nondepressed monkeys. Glial numbers were 30% lower in anterior CA1 and DG of depressed monkeys, with no differences observed in the posterior hippocampus. Granule neuron number tended toward a reduction in anterior DG; pyramidal neuron number was unchanged in any region. Size of pyramidal neurons and glial densities tended to be reduced throughout the whole hippocampus of depressed monkeys, whereas neuronal densities were unchanged. CONCLUSIONS: The reduced size of the anterior hippocampus in depressed female monkeys appears to arise from alterations in numbers of glia and extent of neuropil, but not numbers of neurons, in CA1 and DG.


Assuntos
Depressão/patologia , Hipocampo/patologia , Neurônios/patologia , Neurópilo/patologia , Animais , Contagem de Células , Dexametasona , Modelos Animais de Doenças , Feminino , Hierarquia Social , Hidrocortisona/sangue , Macaca fascicularis , Fosfopiruvato Hidratase/metabolismo , Progesterona/sangue , Estatísticas não Paramétricas , Técnicas Estereotáxicas , Esteroides/sangue
20.
Radiat Res ; 178(1): 46-56, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22687052

RESUMO

We hypothesized that chronic administration of the angiotensin-converting enzyme inhibitor, ramipril, to young adult male rats would prevent/ameliorate fractionated whole-brain irradiation-induced perirhinal cortex-dependent cognitive impairment. Eighty 12-14-week-old young adult male Fischer 344 rats received either: (1) sham irradiation, (2) 40 Gy of fractionated whole-brain irradiation delivered as two 5 Gy fractions/week for 4 weeks, (3) sham irradiation plus continuous administration of 15 mg/L of ramipril in the drinking water starting 3 days before irradiation, or (4) fractionated whole-brain irradiation plus ramipril. Cognitive function was assessed using a perirhinal cortex-dependent version of the novel object recognition task 26 weeks after irradiation. Microglial activation was determined in the perirhinal cortex and the dentate gyrus of the hippocampus 28 weeks after irradiation using the ED1 antibody. Neurogenesis was assessed in the granular cell layer and subgranular zones of the dentate gyrus using a doublecortin antibody. Fractionated whole-brain irradiation led to: (1) a significant impairment in perirhinal cortex-dependent cognitive function, (2) a significant increase in activated microglia in the dentate gyrus but not in the perirhinal cortex, and (3) a significant decrease in neurogenesis. Continuous administration of ramipril before, during, and after irradiation prevented the fractionated whole-brain irradiation-induced changes in perirhinal cortex-dependent cognitive function, as well as in microglial activation in the dentate gyrus. Thus, as hypothesized, continuous administration of the angiotensin-converting enzyme inhibitor, ramipril, can prevent the fractionated whole-brain irradiation-induced impairment in perirhinal cortex-dependent cognitive function.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Córtex Cerebral/efeitos da radiação , Transtornos Cognitivos/prevenção & controle , Irradiação Craniana/efeitos adversos , Lesões Experimentais por Radiação/prevenção & controle , Ramipril/uso terapêutico , Angiotensina I/sangue , Animais , Peso Corporal , Córtex Cerebral/fisiologia , Transtornos Cognitivos/etiologia , Fracionamento da Dose de Radiação , Proteína Duplacortina , Masculino , Ratos , Ratos Endogâmicos F344
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