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1.
Ann Oncol ; 30(5): 774-780, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30860570

RESUMO

BACKGROUND: BEECH investigated the efficacy of capivasertib (AZD5363), an oral inhibitor of AKT isoforms 1-3, in combination with the first-line weekly paclitaxel for advanced or metastatic estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer, and in a phosphoinositide 3-kinase, catalytic, alpha polypeptide mutation sub-population (PIK3CA+). PATIENTS AND METHODS: BEECH consisted of an open-label, phase Ib safety run-in (part A) in 38 patients with advanced breast cancer, and a randomised, placebo-controlled, double-blind, phase II expansion (part B) in 110 women with ER+/HER2- metastatic breast cancer. In part A, patients received paclitaxel 90 mg/m2 (days 1, 8 and 15 of a 28-day cycle) with capivasertib taken twice daily (b.i.d.) at two intermittent ascending dosing schedules. In part B, patients were randomly assigned, stratified by PIK3CA mutation status, to receive paclitaxel with either capivasertib or placebo. The primary end point for part A was safety to recommend a dose and schedule for part B; primary end points for part B were progression-free survival (PFS) in the overall and PIK3CA+ sub-population. RESULTS: Capivasertib was well tolerated, with a 400 mg b.i.d. 4 days on/3 days off treatment schedule selected in part A. In part B, median PFS in the overall population was 10.9 months with capivasertib versus 8.4 months with placebo [hazard ratio (HR) 0.80; P = 0.308]. In the PIK3CA+ sub-population, median PFS was 10.9 months with capivasertib versus 10.8 months with placebo (HR 1.11; P = 0.760). Based on the Common Terminology Criteria for Adverse Event v4.0, the most common grade ≥3 adverse events in the capivasertib group were diarrhoea, hyperglycaemia, neutropoenia and maculopapular rash. Dose intensity of paclitaxel was similar in both groups. CONCLUSIONS: Capivasertib had no apparent impact on the tolerability and dose intensity of paclitaxel. Adding capivasertib to weekly paclitaxel did not prolong PFS in the overall population or PIK3CA+ sub-population of ER+/HER2- advanced/metastatic breast cancer patients.ClinicalTrials.gov: NCT01625286.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Método Duplo-Cego , Feminino , Humanos , Mutação , Metástase Neoplásica , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Taxa de Sobrevida
2.
Mol Psychiatry ; 23(8): 1764-1772, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29311665

RESUMO

Scientists have long sought to characterize the pathophysiologic basis of schizophrenia and develop biomarkers that could identify the illness. Extensive postmortem and in vivo neuroimaging research has described the early involvement of the hippocampus in the pathophysiology of schizophrenia. In this context, we have developed a hypothesis that describes the evolution of schizophrenia-from the premorbid through the prodromal stages to syndromal psychosis-and posits dysregulation of glutamate neurotransmission beginning in the CA1 region of the hippocampus as inducing attenuated psychotic symptoms and initiating the transition to syndromal psychosis. As the illness progresses, this pathological process expands to other regions of the hippocampal circuit and projection fields in other anatomic areas including the frontal cortex, and induces an atrophic process in which hippocampal neuropil is reduced and interneurons are lost. This paper will describe the studies of our group and other investigators supporting this pathophysiological hypothesis, as well as its implications for early detection and therapeutic intervention.


Assuntos
Hipocampo/fisiopatologia , Esquizofrenia/fisiopatologia , Animais , Hipocampo/diagnóstico por imagem , Humanos , Modelos Neurológicos , Esquizofrenia/diagnóstico
3.
Psychol Med ; 47(11): 1923-1935, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28249639

RESUMO

BACKGROUND: DSM-5 proposes an Attenuated Psychosis Syndrome (APS) for further investigation, based upon the Attenuated Positive Symptom Syndrome (APSS) in the Structured Interview for Psychosis-Risk Syndromes (SIPS). SIPS Unusual Thought Content, Disorganized Communication and Total Disorganization scores predicted progression to psychosis in a 2015 NAPLS-2 Consortium report. We sought to independently replicate this in a large single-site high-risk cohort, and identify baseline demographic and clinical predictors beyond current APS/APSS criteria. METHOD: We prospectively studied 200 participants meeting criteria for both the SIPS APSS and DSM-5 APS. SIPS scores, demographics, family history of psychosis, DSM Axis-I diagnoses, schizotypy, and social and role functioning were assessed at baseline, with follow-up every 3 months for 2 years. RESULTS: The conversion rate was 30% (n = 60), or 37.7% excluding participants who were followed under 2 years. This rate was stable across time. Conversion time averaged 7.97 months for 60% who developed schizophrenia and 15.68 for other psychoses. Mean conversion age was 20.3 for males and 23.5 for females. Attenuated odd ideas and thought disorder appear to be the positive symptoms which best predict psychosis in a logistic regression. Total negative symptom score, Asian/Pacific Islander and Black/African-American race were also predictive. As no Axis-I diagnosis or schizotypy predicted conversion, the APS is supported as a distinct syndrome. In addition, cannabis use disorder did not increase risk of conversion to psychosis. CONCLUSIONS: NAPLS SIPS findings were replicated while controlling for clinical and demographic factors, strongly supporting the validity of the SIPS APSS and DSM-5 APS diagnosis.


Assuntos
Progressão da Doença , Sintomas Prodrômicos , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Prognóstico , Transtornos Psicóticos/diagnóstico , Risco , Esquizofrenia/diagnóstico , Adulto Jovem
4.
Opt Lett ; 40(13): 2957-60, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26125341

RESUMO

Talbot effect is a well known optical phenomenon that can be used to perform passive coherent laser combination. Using an appropriately configured Talbot cavity, an array of laser elements can be forced to oscillate in a single supermode with a spatially coherent output. One disadvantage of the Talbot cavity is the high loss incurred when the array is configured to provide good supermode discrimination. In this Letter, we present a new arrangement of the laser elements in the cavity with all of the elements pointing toward the common center of the array in the plane of the coupled feedback. This configuration provides significantly increased supermode discrimination along with significantly reduced loss.

5.
Psychol Med ; 45(14): 2959-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26040537

RESUMO

BACKGROUND: Schizophrenia is characterized by profound and disabling deficits in the ability to recognize emotion in facial expression and tone of voice. Although these deficits are well documented in established schizophrenia using recently validated tasks, their predictive utility in at-risk populations has not been formally evaluated. METHOD: The Penn Emotion Recognition and Discrimination tasks, and recently developed measures of auditory emotion recognition, were administered to 49 clinical high-risk subjects prospectively followed for 2 years for schizophrenia outcome, and 31 healthy controls, and a developmental cohort of 43 individuals aged 7-26 years. Deficit in emotion recognition in at-risk subjects was compared with deficit in established schizophrenia, and with normal neurocognitive growth curves from childhood to early adulthood. RESULTS: Deficits in emotion recognition significantly distinguished at-risk patients who transitioned to schizophrenia. By contrast, more general neurocognitive measures, such as attention vigilance or processing speed, were non-predictive. The best classification model for schizophrenia onset included both face emotion processing and negative symptoms, with accuracy of 96%, and area under the receiver-operating characteristic curve of 0.99. In a parallel developmental study, emotion recognition abilities were found to reach maturity prior to traditional age of risk for schizophrenia, suggesting they may serve as objective markers of early developmental insult. CONCLUSIONS: Profound deficits in emotion recognition exist in at-risk patients prior to schizophrenia onset. They may serve as an index of early developmental insult, and represent an effective target for early identification and remediation. Future studies investigating emotion recognition deficits at both mechanistic and predictive levels are strongly encouraged.


Assuntos
Discriminação Psicológica , Emoções , Expressão Facial , Reconhecimento Psicológico , Esquizofrenia/diagnóstico , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Prognóstico , Escalas de Graduação Psiquiátrica , Adulto Jovem
6.
Psychol Med ; 43(2): 259-68, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22651857

RESUMO

BACKGROUND: Increased sensitivity and exposure to stress are associated with psychotic symptoms in schizophrenia and its risk states, but little is known about the co-evolution of stress sensitivity and exposure with positive and other symptoms in a clinical high-risk (CHR) cohort. METHOD: A combined cross-sectional and longitudinal design was used to examine the associations over time of stress sensitivity and exposure (i.e. life events) with 'prodromal' symptoms in a cohort of 65 CHR patients assessed quarterly for up to 4 years, and at baseline in 24 healthy controls similar in age and gender. RESULTS: Impaired stress tolerance was greater in patients, in whom it was associated over time with positive and negative symptoms, in addition to depression, anxiety and poor function. By contrast, life events were comparable in patients and controls, and bore no association with symptoms. In this treated cohort, there was a trajectory of improvement in stress tolerance, symptoms and function over time. CONCLUSIONS: Impaired stress tolerance was associated with a wide range of 'prodromal' symptoms, consistent with it being a core feature of the psychosis risk state. Self-reported life events were not relevant as a correlate of clinical status. As in other treated CHR cohorts, most patients improved over time across symptom domains.


Assuntos
Modelos Estatísticos , Sintomas Prodrômicos , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Estresse Psicológico/epidemiologia , Adolescente , Adulto , Criança , Estudos Transversais , Suscetibilidade a Doenças/epidemiologia , Feminino , Humanos , Acontecimentos que Mudam a Vida , Estudos Longitudinais , Masculino , New York/epidemiologia , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/psicologia , Fatores de Risco , Estresse Psicológico/psicologia , Fatores de Tempo , Adulto Jovem
7.
Schizophr Res ; 259: 80-87, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36732110

RESUMO

AIM: Psychotic symptoms are typically measured using clinical ratings, but more objective and sensitive metrics are needed. Hence, we will assess thought disorder using the Research Domain Criteria (RDoC) heuristic for language production, and its recommended paradigm of "linguistic corpus-based analyses of language output". Positive thought disorder (e.g., tangentiality and derailment) can be assessed using word-embedding approaches that assess semantic coherence, whereas negative thought disorder (e.g., concreteness, poverty of speech) can be assessed using part-of-speech (POS) tagging to assess syntactic complexity. We aim to establish convergent validity of automated linguistic metrics with clinical ratings, assess normative demographic variance, determine cognitive and functional correlates, and replicate their predictive power for psychosis transition among at-risk youths. METHODS: This study will assess language production in 450 English-speaking individuals in Australia and Canada, who have recent onset psychosis, are at clinical high risk (CHR) for psychosis, or who are healthy volunteers, all well-characterized for cognition, function and symptoms. Speech will be elicited using open-ended interviews. Audio files will be transcribed and preprocessed for automated natural language processing (NLP) analyses of coherence and complexity. Data analyses include canonical correlation, multivariate linear regression with regularization, and machine-learning classification of group status and psychosis outcome. CONCLUSIONS: This prospective study aims to characterize language disturbance across stages of psychosis using computational approaches, including psychometric properties, normative variance and clinical correlates, important for biomarker development. SPEAK will create a large archive of language data available to other investigators, a rich resource for the field.


Assuntos
Transtornos Psicóticos , Adolescente , Humanos , Estudos Prospectivos , Transtornos Psicóticos/complicações , Transtornos Psicóticos/diagnóstico , Linguística , Idioma , Fala
8.
Int J Geriatr Psychiatry ; 27(12): 1248-57, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22374884

RESUMO

OBJECTIVE: The use of psychotropic medications in Alzheimer's disease (AD) has been associated with both deleterious and potentially beneficial outcomes. We examined the longitudinal association of psychotropic medication use with cognitive, functional, and neuropsychiatric symptom (NPS) trajectories among community-ascertained incident AD cases from the Cache County Dementia Progression Study. METHODS: A total of 230 participants were followed for a mean of 3.7 years. Persistency index (PI) was calculated for all antidepressants, selective serotonin reuptake inhibitors (SSRIs), antipsychotics (atypical and typical), and benzodiazepines as the proportion of observed time of medication exposure. Mixed-effects models were used to examine the association between PI for each medication class and Mini-Mental State Exam (MMSE), Clinical Dementia Rating Sum of Boxes (CDR-Sum), and Neuropsychiatric Inventory - Total (NPI-Total) trajectories, controlling for appropriate demographic and clinical covariates. RESULTS: At baseline, psychotropic medication use was associated with greater severity of dementia and poorer medical status. Higher PI for all medication classes was associated with a more rapid decline in MMSE. For antidepressant, SSRI, benzodiazepine, and typical antipsychotic use, a higher PI was associated with a more rapid increase in CDR-Sum. For SSRIs, antipsychotics, and typical antipsychotics, a higher PI was associated with more rapid increase in NPI-Total. CONCLUSIONS: Psychotropic medication use was associated with more rapid cognitive and functional decline in AD, and not with improved NPS. Clinicians may tend to prescribe psychotropic medications to AD patients at risk of poorer outcomes, but one cannot rule out the possibility of poorer outcomes being caused by psychotropic medications.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Cognição/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/psicologia , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica
9.
Psychol Med ; 41(2): 251-61, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20444306

RESUMO

BACKGROUND: Social dysfunction is a hallmark symptom of schizophrenia which commonly precedes the onset of psychosis. It is unclear if social symptoms in clinical high-risk patients reflect depressive symptoms or are a manifestation of negative symptoms. METHOD: We compared social function scores on the Social Adjustment Scale-Self Report between 56 young people (aged 13-27 years) at clinical high risk for psychosis and 22 healthy controls. The cases were also assessed for depressive and 'prodromal' symptoms (subthreshold positive, negative, disorganized and general symptoms). RESULTS: Poor social function was related to both depressive and negative symptoms, as well as to disorganized and general symptoms. The symptoms were highly intercorrelated but linear regression analysis demonstrated that poor social function was primarily explained by negative symptoms within this cohort, particularly in ethnic minority patients. CONCLUSIONS: Although this study demonstrated a relationship between social dysfunction and depressive symptoms in clinical high-risk cases, this association was primarily explained by the relationship of each of these to negative symptoms. In individuals at heightened risk for psychosis, affective changes may be related to a progressive decrease in social interaction and loss of reinforcement of social behaviors. These findings have relevance for potential treatment strategies for social dysfunction in schizophrenia and its risk states and predict that antidepressant drugs, cognitive behavioral therapy and/or social skills training may be effective.


Assuntos
Depressão , Transtornos Psicóticos/psicologia , Psicologia do Esquizofrênico , Ajustamento Social , Adolescente , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Modelos Lineares , Masculino , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/etnologia , Medição de Risco , Esquizofrenia/diagnóstico , Esquizofrenia/etnologia , Estados Unidos
10.
Clin Genet ; 78(4): 321-33, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20681996

RESUMO

The hippocampus is a primary region of the brain controlling the formation of memories and learned behaviours. The ability to learn or form a memory requires a neuron to translate a transient signal into gene expression changes that have a long-lasting effect on synapse activity and connectivity. Numerous studies over the past decade have detailed changes in epigenetic modifications under various learning paradigms to support a role for chromatin remodelling in these processes. Moreover, the identification of mutations in epigenetic regulators as the cause of mental retardation or intellectual disability (MR/ID) disorders further strengthens their importance to learning and memory. Animal models for many of these disorders are emerging and advancing our understanding of the molecular mechanisms linking epigenetic regulation and cognitive function. Here, we review how chromatin remodelling proteins implicated in MR/ID contribute to the development of the hippocampus and memory formation.


Assuntos
Transtornos Cognitivos/genética , Epigênese Genética , Hipocampo/embriologia , Hipocampo/fisiologia , Deficiência Intelectual/genética , Animais , Montagem e Desmontagem da Cromatina , Transtornos Cognitivos/fisiopatologia , Metilação de DNA , Hipocampo/metabolismo , Histonas/genética , Histonas/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Camundongos , Mutação
11.
Dev Psychobiol ; 52(5): 465-74, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20583143

RESUMO

The mother-infant dyad is crucial to early development in a variety of species. The complexity of social groupings in nonhuman primates makes this relationship resilient as well as susceptible to early challenges associated with environmental chaos. Quantitative behavior observations of bonnet monkey mother-infant interactions were collected from 28 mother-infant dyads between one and twelve months of age. Social groups were subjected to several prenatal and/or postnatal housing relocations within a single year resulting in two study groups. One group experienced relocations (ATYPICAL, n = 14) and the second group (TYPICAL, n = 14) was conceived and reared in the same location. Behaviors in the ethogram included mother-infant interactions and infant social interactions with other members of the group. Observations between ages of two to four months were analyzed by a mixed model analysis of variance including fixed effects of per and postnatal history (TYPICAL, ATYPICAL), age, and history by age interaction and random effects of mother and infant nested within mother. A significant effect of relocation history was noted on a number of infant behaviors. ATYPICAL infants were out of direct contact with their mother at an earlier age but remained in her proximity. Control of proximity shifted to offsrping in the ATYPICAL group compared to the TYPICAL group. Furthermore, greater social interactions between two and four months of age with other members of the social group as well as the ir mother were observed in the ATYPICAL group. It is suggested that continuous challenge associated with relocation may affect the infant at later developmental ages due to these early differences in ways that are yet unclear.


Assuntos
Macaca radiata/psicologia , Comportamento Materno/psicologia , Apego ao Objeto , Comportamento Social , Meio Social , Identificação Social , Animais , Nível de Alerta , Feminino , Masculino , Gravidez
12.
Eur Psychiatry ; 63(1): e72, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32778184

RESUMO

BACKGROUND: Abnormalities in the semantic and syntactic organization of speech have been reported in individuals at clinical high-risk (CHR) for psychosis. The current study seeks to examine whether such abnormalities are associated with changes in brain structure and functional connectivity in CHR individuals. METHODS: Automated natural language processing analysis was applied to speech samples obtained from 46 CHR and 22 healthy individuals. Brain structural and resting-state functional imaging data were also acquired from all participants. Sparse canonical correlation analysis (sCCA) was used to ascertain patterns of covariation between linguistic features, clinical symptoms, and measures of brain morphometry and functional connectivity related to the language network. RESULTS: In CHR individuals, we found a significant mode of covariation between linguistic and clinical features (r = 0.73; p = 0.003), with negative symptoms and bizarre thinking covarying mostly with measures of syntactic complexity. In the entire sample, separate sCCAs identified a single mode of covariation linking linguistic features with brain morphometry (r = 0.65; p = 0.05) and resting-state network connectivity (r = 0.63; p = 0.01). In both models, semantic and syntactic features covaried with brain structural and functional connectivity measures of the language network. However, the contribution of diagnosis to both models was negligible. CONCLUSIONS: Syntactic complexity appeared sensitive to prodromal symptoms in CHR individuals while the patterns of brain-language covariation seemed preserved. Further studies in larger samples are required to establish the reproducibility of these findings.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Linguística , Imagem Multimodal , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Adulto , Feminino , Humanos , Masculino , Processamento de Linguagem Natural , Sintomas Prodrômicos , Transtornos Psicóticos/diagnóstico , Adulto Jovem
13.
J Cell Biol ; 134(4): 985-1001, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8769422

RESUMO

The desmosomal plaque protein desmoplakin (DP), located at the juncture between the intermediate filament (IF) network and the cytoplasmic tails of the transmembrane desmosomal cadherins, has been proposed to link IF to the desmosomal plaque. Consistent with this hypothesis, previous studies of individual DP domains indicated that the DP COOH terminus associates with IF networks whereas NH2-terminal sequences govern the association of DP with the desmosomal plaque. Nevertheless, it had not yet been demonstrated that DP is required for attaching IF to the desmosome. To test this proposal directly, we generated A431 cell lines stably expressing DP NH2-terminal polypeptides, which were expected to compete with endogenous DP during desmosome assembly. As these polypeptides lacked the COOH-terminal IF-binding domain, this competition should result in the loss of IF anchorage if DP is required for linking IF to the desmosomal plaque. In such cells, a 70-kD DP NH2-terminal polypeptide (DP-NTP) colocalized at cell-cell interfaces with desmosomal proteins. As predicted, the distribution of endogenous DP was severely perturbed. At cell-cell borders where endogenous DP was undetectable by immunofluorescence, there was a striking absence of attached tonofibrils (IF bundles). Furthermore, DP-NTP assembled into ultrastructurally identifiable junctional structures lacking associated IF bundles. Surprisingly, immunofluorescence and immunogold electron microscopy indicated that adherens junction components were coassembled into these structures along with desmosomal components and DP-NTP. These results indicate that DP is required for anchoring IF networks to desmosomes and furthermore suggest that the DP-IF complex is important for governing the normal spatial segregation of adhesive junction components during their assembly into distinct structures.


Assuntos
Adesão Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Desmossomos/metabolismo , Junções Intercelulares/metabolismo , Filamentos Intermediários/metabolismo , Transativadores , Caderinas/análise , Carcinoma de Células Escamosas , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/química , Desmoplaquinas , Desmossomos/química , Células Epiteliais , Epitélio/química , Epitélio/metabolismo , Humanos , Junções Intercelulares/ultraestrutura , Filamentos Intermediários/ultraestrutura , Queratinas/metabolismo , Dados de Sequência Molecular , Peso Molecular , Peptídeos , Proteínas Recombinantes de Fusão/biossíntese , Células Tumorais Cultivadas , alfa Catenina , beta Catenina
14.
J Cell Biol ; 123(3): 691-705, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7693716

RESUMO

We previously demonstrated that truncated desmoplakin I (DP I) molecules containing the carboxyl terminus specifically coalign with and disrupt both keratin and vimentin intermediate filament (IF) networks when overexpressed in tissue culture cells (Stappenbeck, T. S., and K. J. Green. J. Cell Biol. 116:1197-1209). These experiments suggested that the DP carboxyl-terminal domain is involved either directly or indirectly in linking IF with the desmosome. Using a similar approach, we have now investigated the behavior of ectopically expressed full-length DP I in cultured cells. In addition, we have further dissected the functional sequences in the carboxyl terminus of DP I that facilitate the interaction with IF networks. Transient transfection of a clone encoding full-length DP I into COS-7 cells produced protein that appeared in some cells to associate with desmosomes and in others to coalign with and disrupt IF. Deletion of the carboxyl terminus from this clone resulted in protein that still appeared capable of associating with desmosomes but not interacting with IF networks. As the amino terminus appeared to be dispensable for IF interaction, we made finer deletions in the carboxyl terminus of DP based on blocks of sequence similarity with the related molecules bullous pemphigoid antigen and plectin. We found a sequence at the very carboxyl terminus of DP that was necessary for coalignment with and disruption of keratin IF but not vimentin IF. Furthermore, the coalignment of specific DP proteins along keratin IF but not vimentin IF was correlated with resistance to extraction by Triton. The striking uncoupling resulting from the deletion of specific DP sequences suggests that the carboxyl terminus of DP interacts differentially with keratin and vimentin IF networks.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Desmossomos/metabolismo , Filamentos Intermediários/metabolismo , Queratinas/metabolismo , Vimentina/metabolismo , Células 3T3 , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Sítios de Ligação , Linhagem Celular , Chlorocebus aethiops , Clonagem Molecular , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/química , Desmoplaquinas , Desmossomos/ultraestrutura , Imunofluorescência , Genes myc , Células HeLa , Humanos , Filamentos Intermediários/ultraestrutura , Rim , Camundongos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Transfecção
15.
J Cell Biol ; 139(3): 773-84, 1997 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-9348293

RESUMO

The desmosome is a highly organized plasma membrane domain that couples intermediate filaments to the plasma membrane at regions of cell-cell adhesion. Desmosomes contain two classes of cadherins, desmogleins, and desmocollins, that bind to the cytoplasmic protein plakoglobin. Desmoplakin is a desmosomal component that plays a critical role in linking intermediate filament networks to the desmosomal plaque, and the amino-terminal domain of desmoplakin targets desmoplakin to the desmosome. However, the desmosomal protein(s) that bind the amino-terminal domain of desmoplakin have not been identified. To determine if the desmosomal cadherins and plakoglobin interact with the amino-terminal domain of desmoplakin, these proteins were co-expressed in L-cell fibroblasts, cells that do not normally express desmosomal components. When expressed in L-cells, the desmosomal cadherins and plakoglobin exhibited a diffuse distribution. However, in the presence of an amino-terminal desmoplakin polypeptide (DP-NTP), the desmosomal cadherins and plakoglobin were observed in punctate clusters that also contained DP-NTP. In addition, plakoglobin and DP-NTP were recruited to cell-cell interfaces in L-cells co-expressing a chimeric cadherin with the E-cadherin extracellular domain and the desmoglein-1 cytoplasmic domain, and these cells formed structures that were ultrastructurally similar to the outer plaque of the desmosome. In transient expression experiments in COS cells, the recruitment of DP-NTP to cell borders by the chimera required co-expression of plakoglobin. Plakoglobin and DP-NTP co-immunoprecipitated when extracted from L-cells, and yeast two hybrid analysis indicated that DP-NTP binds directly to plakoglobin but not Dsg1. These results identify a role for desmoplakin in organizing the desmosomal cadherin-plakoglobin complex and provide new insights into the hierarchy of protein interactions that occur in the desmosomal plaque.


Assuntos
Caderinas/metabolismo , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/fisiologia , Desmossomos/metabolismo , Estrutura Terciária de Proteína , Animais , Caderinas/química , Caderinas/genética , Citoplasma/química , Citoplasma/metabolismo , Desmocolinas , Desmogleína 1 , Desmogleínas , Desmoplaquinas , Desmossomos/química , Desmossomos/genética , Espaço Extracelular/química , Espaço Extracelular/genética , Humanos , Células L , Substâncias Macromoleculares , Camundongos , Peptídeos/metabolismo , Peptídeos/fisiologia , Ligação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/fisiologia , alfa Catenina , gama Catenina
16.
BMC Psychiatry ; 8: 71, 2008 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-18717990

RESUMO

UNLABELLED: Schizophrenia has been linked with intrauterine exposure to maternal stress due to bereavement, famine and major disasters. Recent evidence suggests that human vulnerability may be greatest in the first trimester of gestation and rodent experiments suggest sex specificity. We aimed to describe the consequence of an acute maternal stress, through a follow-up of offspring whose mothers were pregnant during the Arab-Israeli war of 1967. A priori, we focused on gestational month and offspring's sex. METHOD: In a pilot study linking birth records to Israel's Psychiatric Registry, we analyzed data from a cohort of 88,829 born in Jerusalem in 1964-76. Proportional hazards models were used to estimate the relative risk (RR) of schizophrenia, according to month of birth, gender and other variables, while controlling for father's age and other potential confounders. Other causes of hospitalized psychiatric morbidity (grouped together) were analyzed for comparison. RESULTS: There was a raised incidence of schizophrenia for those who were in the second month of fetal life in June 1967 (RR = 2.3, 1.1-4.7), seen more in females (4.3, 1.7-10.7) than in males (1.2, 0.4-3.8). Results were not explained by secular or seasonal variations, altered birth weight or gestational age. For other conditions, RRs were increased in offspring who had been in the third month of fetal life in June 1967 (2.5, 1.2-5.2), also seen more in females (3.6, 1.3-9.7) than males (1.8, 0.6-5.2). CONCLUSION: These findings add to a growing literature, in experimental animals and humans, attributing long term consequences for offspring of maternal gestational stress. They suggest both a sex-specificity and a relatively short gestational time-window for gestational effects on vulnerability to schizophrenia.


Assuntos
Mães/psicologia , Mães/estatística & dados numéricos , Esquizofrenia/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Doença Aguda , Criança , Estudos de Coortes , Feminino , Humanos , Israel/epidemiologia , Masculino , Projetos Piloto , Gravidez , Estudos Prospectivos , Fatores Sexuais
17.
Schizophr Res ; 97(1-3): 25-34, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17884347

RESUMO

Schizophrenia has been associated with deficits in visual perception and processing, but there is little information about their temporal development and stability. We assessed visual form perception using the Rorschach Comprehensive System (RCS) in 23 individuals at clinical high risk for psychosis, 15 individuals with recent onset schizophrenia (< or =2 years since onset), and 34 with chronic schizophrenia (> or =3 years since onset). All three groups demonstrated reduced conventional form perception (X+%), as compared with published norms, but did not differ significantly from one another. In contrast, the high-risk group had significantly better performance on an index of clarity of conceptual thinking (WSUM6) compared to the chronic schizophrenia patients, with the recent onset group scoring intermediate to the high-risk and chronic schizophrenia groups. The results suggest that individuals at clinical high risk for psychosis display substantial deficits in visual form perception prior to the onset of psychosis and that these deficits are comparable in severity to those observed in individuals with schizophrenia. Therefore, visual form perception deficits may constitute a trait-like risk factor for psychosis in high-risk individuals and may potentially serve as an endophenotype of risk for development of psychosis. Clarity of conceptual thinking was relatively preserved among high-risk patients, consistent with a relationship to disease expression, not risk. These deficits are discussed in the context of the putative neurobiological underpinnings of visual deficits and the developmental pathophysiology of psychosis in schizophrenia.


Assuntos
Formação de Conceito , Reconhecimento Visual de Modelos , Transtornos Psicóticos/diagnóstico , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adolescente , Adulto , Doença Crônica , Discriminação Psicológica , Feminino , Humanos , Masculino , Distorção da Percepção , Fenótipo , Psicometria , Transtornos Psicóticos/psicologia , Teste de Realidade , Valores de Referência , Teste de Rorschach/estatística & dados numéricos , Pensamento
18.
J Nutr Health Aging ; 11(3): 230-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17508099

RESUMO

OBJECTIVE: We prospectively examined associations between intakes of antioxidants (vitamins C, vitamin E, and carotene) and cognitive function and decline among elderly men and women of the Cache County Study on Memory and Aging in Utah. PARTICIPANTS AND DESIGN: In 1995, 3831 residents 65 years of age or older completed a baseline survey that included a food frequency questionnaire and cognitive assessment. Cognitive function was assessed using an adapted version of the Modified Mini-Mental State examination (3MS) at baseline and at three subsequent follow-up interviews spanning approximately 7 years. Multivariable-mixed models were used to estimate antioxidant nutrient effects on average 3MS score over time. RESULTS: Increasing quartiles of vitamin C intake alone and combined with vitamin E were associated with higher baseline average 3MS scores (p-trend = 0.013 and 0.02 respectively); this association appeared stronger for food sources compared to supplement or food and supplement sources combined. Study participants with lower levels of intake of vitamin C, vitamin E and carotene had a greater acceleration of the rate of 3MS decline over time compared to those with higher levels of intake. CONCLUSION: High antioxidant intake from food and supplement sources of vitamin C, vitamin E, and carotene may delay cognitive decline in the elderly.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Carotenoides/administração & dosagem , Transtornos Cognitivos/prevenção & controle , Cognição/efeitos dos fármacos , Vitamina E/administração & dosagem , Idoso , Transtornos Cognitivos/etiologia , Escolaridade , Comportamento Alimentar , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Testes Psicológicos , Inquéritos e Questionários , Utah
19.
Arch Gen Psychiatry ; 58(8): 763-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11483142

RESUMO

BACKGROUND: Cognitive deficits are a major determinant of social and occupational dysfunction in schizophrenia. In this study, we determined whether neurocognitive enhancement therapy (NET) in combination with work therapy (WT) would improve performance on neuropsychological tests related to but different from the training tasks. METHODS: Sixty-five patients with schizophrenia or schizoaffective disorder were randomly assigned to NET plus WT or WT alone. Neurocognitive enhancement therapy included computer-based training on attention, memory, and executive function tasks; an information processing group; and feedback on cognitive performance in the workplace. Work therapy included paid work activity in job placements at the medical center (eg, mail room, grounds, library) with accompanying supports. Neuropsychological testing was performed at intake and 5 months later. RESULTS: Prior to enrollment, both groups did poorly on neuropsychological testing. Patients receiving NET + WT showed greater improvements on pretest-posttest variables of executive function, working memory, and affect recognition. As many as 60% in the NET + WT group improved on some measures and were 4 to 5 times more likely to show large effect-size improvements. The number of patients with normal working memory performance increased significantly with NET + WT, from 45% to 77%, compared with a decrease from 56% to 45% for those receiving WT. CONCLUSIONS: Computer training for cognitive dysfunction in patients with schizophrenia can have benefits that generalize to independent outcome measures. Efficacy may result from a synergy between NET, which encourages mental activity, and WT, which allows a natural context for mental activity to be exercised, generalized, and reinforced.


Assuntos
Transtornos Cognitivos/terapia , Cognição/fisiologia , Testes Neuropsicológicos/estatística & dados numéricos , Terapia Ocupacional/métodos , Esquizofrenia/terapia , Ensino/métodos , Adulto , Atenção/fisiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Instrução por Computador/métodos , Testes com Listas de Dissílabos/métodos , Retroalimentação , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Memória/fisiologia , Análise Multivariada , Desempenho Psicomotor/fisiologia , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Transtornos Psicóticos/terapia , Psicologia do Esquizofrênico , Resultado do Tratamento
20.
J Clin Endocrinol Metab ; 83(12): 4251-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9851759

RESUMO

It is unknown whether hypogonadism contributes to decreased insulin-like growth factor I (IGF-I) production and/or how testosterone administration may effect the GH-IGF-I axis in human immunodeficiency virus (HIV)-infected men with the acquired immunodeficiency syndrome (AIDS) wasting syndrome (AWS). In this study, we investigate the GH-IGF-I axis in men with the AWS and determine the effects of testosterone on GH secretory dynamics, pulse characteristics determined from overnight frequent sampling, arginine stimulation, and total and free IGF-I levels. Baseline GH-IGF-I parameters in hypogonadal men with AWS (n=51) were compared before testosterone administration (300 mg, im, every 3 weeks vs. placebo for 6 months) with cross-sectional data obtained in two age-matched control groups: eugonadal men with AIDS wasting (n=10) and healthy age-matched normal men (n=15). The changes in GH-IGF-I parameters were then compared prospectively in testosterone- and placebo-treated patients. Mean overnight GH levels [1.8+/-0.3 and 2.4+/-0.3 vs. 0.90+/-0.1 microg/L (P=0.04 and P=0.003 vs. healthy controls)] and pulse frequency [0.35+/-0.06 and 0.37+/-0.02 vs. 0.22+/-0.03 pulses/h (P=0.06 and P=0.002 vs. healthy controls)] were comparably elevated in the eugonadal and hypogonadal HIV-positive groups, respectively, compared to those in the healthy control group. No significant differences in pulse amplitude, interpulse interval, or maximal GH stimulation to arginine administration (0.5 g/kg, i.v.) were seen between either the eugonadal and hypogonadal HIV-positive or healthy control patients. In contrast, IGF-I levels were comparably decreased in both HIV-positive groups compared to the healthy control group [143+/-16 and 165+/-14 vs. 216+/-14 microg/L (P=0.004 and P=0.02 vs. healthy controls)]. At baseline, before treatment with testosterone, overnight GH levels were inversely correlated with IGF-I (r=-0.42; P=0.003), percent ideal body weight (r=-0.36; P=0.012), albumin (r=-0.37; P=0.012), and fat mass (r=-0.52; P=0.0002), whereas IGF-I levels correlated with free testosterone (r=0.35; P=0.011) and caloric intake (r=0.32; P= 0.023) in the hypogonadal HIV-positive men. In a stepwise regression model, albumin (P=0.003) and testosterone (P=0.011) were the only significant predictors of GH [mean GH (microg/L)=-1.82 x albumin (g/dL) + 0.003 x total testosterone (microg/L) + 6.5], accounting for 49% of the variation in GH. Mean overnight GH levels decreased significantly in the testosterone-treated patients compared to those in the placebo-treated hypogonadal patients (0.9+/-0.3 vs. 0.2+/-0.4 microg/L; P=0.020). In contrast, no differences in IGF-I or free IGF-I were observed in response to testosterone administration. The decrement in mean overnight GH in response to testosterone treatment was inversely associated with increased fat-free mass (r=-0.49; P= 0.024), which was the only significant variable in a stepwise regression model for change in GH [change in mean GH (microg/L)=-0.197 x kg fat-free mass - 0.53] and accounted for 27% of the variation in the change in GH. In this study, we demonstrate increased basal GH secretion and pulse frequency in association with reduced IGF-I concentrations, consistent with GH resistance, among both hypogonadal and eugonadal men with AIDS wasting. Testosterone administration decreases GH in hypogonadal men with AIDS wasting. The change in GH is best predicted by and is inversely related to the magnitude of the change in lean body mass in response to testosterone administration. These data demonstrate that among hypogonadal men with the AWS, testosterone administration has a significant effect on the GH axis.


Assuntos
Síndrome de Emaciação por Infecção pelo HIV/metabolismo , Hormônio do Crescimento Humano/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Testosterona/uso terapêutico , Adulto , Arginina , Estudos Transversais , Síndrome de Emaciação por Infecção pelo HIV/complicações , Síndrome de Emaciação por Infecção pelo HIV/tratamento farmacológico , Hormônio do Crescimento Humano/fisiologia , Humanos , Hipogonadismo/complicações , Fator de Crescimento Insulin-Like I/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fluxo Pulsátil , Valores de Referência
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