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1.
J Immunol ; 200(5): 1671-1681, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29374074

RESUMO

CD22 (Siglec-2) is a critical regulator of B cell activation and survival. CD22-/- mice generate significantly impaired Ab responses to T cell-independent type 2 (TI-2) Ags, including haptenated Ficoll and pneumococcal polysaccharides, Ags that elicit poor T cell help and activate BCR signaling via multivalent epitope crosslinking. This has been proposed to be due to impaired marginal zone (MZ) B cell development/maintenance in CD22-/- mice. However, mice expressing a mutant form of CD22 unable to bind sialic acid ligands generated normal TI-2 Ab responses, despite significantly reduced MZ B cells. Moreover, mice treated with CD22 ligand-binding blocking mAbs, which deplete MZ B cells, had little effect on TI-2 Ab responses. We therefore investigated the effects of CD22 deficiency on B-1b cells, an innate-like B cell population that plays a key role in TI-2 Ab responses. B-1b cells from CD22-/- mice had impaired BCR-induced proliferation and significantly increased intracellular Ca2+ concentration responses following BCR crosslinking. Ag-specific B-1b cell expansion and plasmablast differentiation following TI-2 Ag immunization was significantly impaired in CD22-/- mice, consistent with reduced TI-2 Ab responses. We generated CD22-/- mice with reduced CD19 levels (CD22-/-CD19+/-) to test the hypothesis that augmented B-1b cell BCR signaling in CD22-/- mice contributes to impaired TI-2 Ab responses. BCR-induced proliferation and intracellular Ca2+ concentration responses were normalized in CD22-/-CD19+/- B-1b cells. Consistent with this, TI-2 Ag-specific B-1b cell expansion, plasmablast differentiation, survival, and Ab responses were rescued in CD22-/-CD19+/- mice. Thus, CD22 plays a critical role in regulating TI-2 Ab responses through regulating B-1b cell signaling thresholds.


Assuntos
Antígenos T-Independentes/imunologia , Linfócitos B/imunologia , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD19/imunologia , Diferenciação Celular/imunologia , Proliferação de Células/fisiologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos B/imunologia , Transdução de Sinais/imunologia
2.
J Clin Exp Neuropsychol ; 45(1): 61-68, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36880743

RESUMO

INTRODUCTION: There are gender disparities in age of diagnosis with Mild Cognitive Impairment (MCI) or dementia, which may be related to general female advantages in verbal memory across aging. Further examination of the serial position effect (SPE) may provide an avenue for earlier diagnosis of MCI/dementia among women. METHOD: 338 cognitively healthy adults aged 50+ (110 men; 228 women) were administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) List Learning task as part of dementia screening. We examined whether the SPE could be demonstrated on Trial 1 and delayed recall, and whether SPE patterns were consistent across genders, using mixed measure ANOVAs. Using regression, we also examined whether gender, SPE components, or their interactions predicted RBANS Delayed Memory Index (DMI) performance. Using cluster analyses, we identified a group with reduced primacy relative to recency on Trial 1 and a group without. We used ANOVA to examine whether clusters differed in DMI scores and whether this was moderated by gender. RESULTS: We demonstrated the prototypical SPE on Trial 1. On delayed recall, we found reduced recency compared to primacy and middle performance. As expected, men exhibited worse performance on the DMI. However, gender did not interact with SPE. Primacy and middle, but not recency, performance on Trial 1 predicted DMI scores, as did the recency ratio. These relationships were not moderated by gender. Finally, participants with better primacy than recency on Trial 1 (N = 187) exhibited higher performance on DMI than participants with better recency than primacy (N = 151). Gender did not interact with cluster membership. CONCLUSION: Our results have important clinical implications in assessment, where focusing on Trial 1 primacy performance and loss of recency between Trial 1 and delayed recall may help to address gender-related delays in age of diagnosis of MCI or dementia.


Assuntos
Demência , Memória , Humanos , Feminino , Masculino , Idoso , Fatores Sexuais , Envelhecimento/psicologia , Rememoração Mental , Testes Neuropsicológicos , Aprendizagem Seriada
3.
Arch Clin Neuropsychol ; 38(7): 1124-1130, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36966744

RESUMO

OBJECTIVE: Daytime sleepiness is commonly reported among older adults. Additionally, aging is associated with a shift toward greater alertness in the morning that wanes throughout the day. The impact of time of day of testing on the relationships between daytime sleepiness and cognition is unknown. METHODS: We explored the effects of time of testing in relation to self-reported daytime sleepiness/current arousal and cognition among 133 older adults. RESULTS: Time of testing moderated the relationship between daytime sleepiness and immediate learning/memory, with greater sleepiness being associated with poorer performance in the afternoon, but not morning. Time of testing also moderated the relationship between current arousal and processing speed, with lower arousal being associated with worse performance in the afternoon. CONCLUSIONS: These findings suggest that time of testing is important to account for when assessing sleepiness and cognition in older adults and that consideration should be given to how sleepiness is measured.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Sonolência , Humanos , Idoso , Testes Neuropsicológicos , Nível de Alerta , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Cognição
4.
Clin Neuropsychol ; 37(5): 1062-1077, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36722174

RESUMO

Objective: There have been attempts to modify the Montreal Cognitive Assessment (MoCA), a brief cognitive screening tool, for use across several Asian countries, but evidence to support the utility of these translations has been limited, particularly for the Vietnamese translation of the MoCA (MoCA-V). This two-part study aimed to evaluate the MoCA-V in a Vietnamese sample. Methods: In the first stage, we examined the relationships between the MoCA-V subscales and common neuropsychological tests among healthy Vietnamese adults (n = 129) and individuals with moderate-to-severe traumatic brain injury (n = 80). In the second stage, we explored the relationship of TBI status (TBI vs non-TBI) and demographic variables to MoCA-V performance and investigated the optimal cut-off score of the MoCA-V using the two samples combined. Results: The MoCA-V Attention, Language, and Executive Function subscales were correlated with the Digit Span Test, Verbal Fluency Test, and Trail Making Test, respectively, across healthy participants and participants with TBI. Global performance on the MoCA-V was predicted by TBI status, education, and age. Our ROC analysis revealed that a cut-off score of 22 offered the best sensitivity (76.3%) and specificity (71.3%) trade-off for identifying cognitive impairment as measured by the MoCA-V. Conclusions: In addition to identifying a cut-off score for cognitive screening, the findings provide support for the validity of the examined MoCA-V subscales and for the MoCA-V's ability to distinguish TBI survivors vs controls. These results may pave the way for larger-scale investigations of the MoCA-V and for the development of more neuropsychological batteries in Vietnamese.


Assuntos
Lesões Encefálicas Traumáticas , Disfunção Cognitiva , Adulto , Humanos , Testes Neuropsicológicos , População do Sudeste Asiático , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Testes de Estado Mental e Demência , Lesões Encefálicas Traumáticas/complicações , Idioma
5.
Clin Neuropsychol ; 37(4): 812-820, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36576117

RESUMO

Objective: A growing body of literature shows the unequivocal importance of incorporating diversity-related factors into the practice of clinical neuropsychology. Thus, it is imperative that we continue to seek and obtain updated training and knowledge on how culture and diversity intersect with our clinical roles throughout our careers, not merely to satisfy initial coursework requirements. Although most professional organizations pertaining to clinical psychology - and thereby neuropsychology - strongly encourage the pursuit of training in diversity-related factors, explicit requirements for such training across one's career are minimal. Method: The Asian Neuropsychological Association Advocacy Committee reviewed continuing education (CE) requirements for all US states. Results: We found that only 8 states mandated CE credits pertaining to diversity-related factors for the renewal of licensure. Discussion: Given how inseparable cultural competence is from any aspect of clinical work (and the harm that can be done if culture is not considered), it is essential that our field shift from aspirational guidance to firm requirements with regard to cultural competence and diversity-related training in psychology. Requiring CE units devoted to diversity-related factors represents one avenue to pursue this goal. This commentary outlines the current status of diversity-related CE for psychology licensure renewal and offers future directions for incorporating such training as a part of continuing professional development and education.


Assuntos
Educação Continuada , Neuropsicologia , Humanos , Testes Neuropsicológicos , Diversidade Cultural , Competência Cultural
6.
J Affect Disord ; 319: 377-380, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162681

RESUMO

BACKGROUND: Anxiety sensitivity (AS), as measured by the Anxiety Sensitivity Index-3 (ASI-3), exhibits three-factor and bifactor structures for younger adults. Less is known about the scale's structure within older adult samples. METHODS: We explored the ASI-3's factor structure in a sample of 135 older adults who completed the ASI-3 alongside measures of anxiety, general worry, dementia worry, and depression as part of a larger study. Structural equation modeling was used to determine the factor structure of the ASI-3 in this sample. RESULTS: A bifactor model was identified and factor loadings supported a general factor and specific physical and cognitive subfactors, but not the social concerns subfactor. Whereas the general factor was associated with anxiety, general worry, dementia worry, and depression, each subfactor had differential associations with these mood/anxiety variables. In particular, the cognitive concerns subfactor was strongly associated with depression and dementia worry. LIMITATIONS: Generalizability of these findings is limited by a homogenous sample. CONCLUSIONS: The observed factor structure of the ASI-3 in our sample aligns with increases in physical and cognitive health concerns during aging. Associations between the cognitive concerns subfactor and dementia worry suggest that this facet of the ASI-3 may be measuring age-related health concerns rather than concerns specific to anxiety symptoms. Future studies should examine whether AS cognitive concerns and dementia worry are overlapping constructs particularly for individuals concerned about their age-related cognitive changes. Age differences in AS and its correlates should be further studied to identify better methods of assessing for AS across the lifespan.


Assuntos
Ansiedade , Demência , Humanos , Idoso , Ansiedade/psicologia , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Transtornos do Humor/diagnóstico , Sintomas Afetivos , Demência/diagnóstico
7.
Artigo em Inglês | MEDLINE | ID: mdl-33076757

RESUMO

Psychosocial factors associated with dementia, such as dementia worry and personal exposure to the illness, may influence the subjective perception of cognitive abilities. The present study examined the relationship of subjective memory concerns with dementia worry, as well as the moderating effects of dementia exposure. Community-dwelling adults aged 50 and above without diagnostic history of dementia or evidence of objective memory impairment completed self-report measures assessing subjective memory concerns, subjective memory decline, dementia worry, depressive symptoms, anxiety symptoms, and dementia exposure. Results revealed that higher subjective memory concerns were associated with greater dementia worry and depressive symptoms. Those with genetic dementia exposure reported higher dementia worry than those with nongenetic or no dementia exposure. Dementia exposure moderated the relationship of subjective memory concerns with dementia worry. These findings suggest that assessments of dementia worry and dementia exposure may be valuable in clinical evaluations of older adults presenting with memory concerns.


Assuntos
Disfunção Cognitiva , Demência , Idoso , Ansiedade , Cognição , Humanos , Transtornos da Memória , Autorrelato
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