RESUMO
AIMS/HYPOTHESIS: Central nervous system abnormalities, including cognitive and brain impairments, have been documented in adults with type 2 diabetes who also have multiple co-morbid disorders that could contribute to these observations. Assessing adolescents with type 2 diabetes will allow the evaluation of whether diabetes per se may adversely affect brain function and structure years before clinically significant vascular disease develops. METHODS: Eighteen obese adolescents with type 2 diabetes and 18 obese controls without evidence of marked insulin resistance, matched on age, sex, school grade, ethnicity, socioeconomic status, body mass index and waist circumference, completed MRI and neuropsychological evaluations. RESULTS: Adolescents with type 2 diabetes performed consistently worse in all cognitive domains assessed, with the difference reaching statistical significance for estimated intellectual functioning, verbal memory and psychomotor efficiency. There were statistical trends for executive function, reading and spelling. MRI-based automated brain structural analyses revealed both reduced white matter volume and enlarged cerebrospinal fluid space in the whole brain and the frontal lobe in particular, but there was no obvious grey matter volume reduction. In addition, assessments using diffusion tensor imaging revealed reduced white and grey matter microstructural integrity. CONCLUSIONS/INTERPRETATION: This is the first report documenting possible brain abnormalities among obese adolescents with type 2 diabetes relative to obese adolescent controls. These abnormalities are not likely to result from education or socioeconomic bias and may result from a combination of subtle vascular changes, glucose and lipid metabolism abnormalities and subtle differences in adiposity in the absence of clinically significant vascular disease. Future efforts are needed to elucidate the underlying pathophysiological mechanisms.
Assuntos
Encéfalo/patologia , Diabetes Mellitus Tipo 2/complicações , Obesidade/complicações , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Circunferência da CinturaRESUMO
Our objective was to ascertain the nature of the associations between C-reactive protein (CRP) and cognition, and to examine how they are affected by gender and obesity. We evaluated 62 females and 63 males between 42 and 82 years of age. There were 20 lean females with a body mass index (BMI) of <25 kg/m2 and 42 overweight or obese females, with BMIs > or =25 kg/m2. There were 14 lean males and 49 with BMIs >/=25 kg/m2. CRP was associated with lower scores on cognitive tests of frontal lobe function among females and these associations were driven by the overweight/obese female group. In these data no associations between CRP and cognition were found among males. Obesity-associated inflammation is much more prominent in females and it appears to be associated with cognitive dysfunction, particularly of frontal lobe tasks.
Assuntos
Proteína C-Reativa/metabolismo , Cognição , Inflamação/sangue , Obesidade/sangue , Sobrepeso/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Índice de Massa Corporal , Feminino , Humanos , Inflamação/etiologia , Inflamação/psicologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/psicologia , Sobrepeso/complicações , Sobrepeso/psicologia , Fatores SexuaisRESUMO
Elevated glucocorticoid levels produce hippocampal dysfunction and correlate with individual deficits in spatial learning in aged rats. Previously we related persistent cortisol increases to memory impairments in elderly humans studied over five years. Here we demonstrate that aged humans with significant prolonged cortisol elevations showed reduced hippocampal volume and deficits in hippocampus-dependent memory tasks compared to normal-cortisol controls. Moreover, the degree of hippocampal atrophy correlated strongly with both the degree of cortisol elevation over time and current basal cortisol levels. Therefore, basal cortisol elevation may cause hippocampal damage and impair hippocampus-dependent learning and memory in humans.
Assuntos
Envelhecimento/sangue , Hipocampo/patologia , Hidrocortisona/sangue , Transtornos da Memória/psicologia , Idoso , Atrofia , Previsões , Humanos , Imageamento por Ressonância Magnética , Memória/fisiologia , Tamanho do Órgão/fisiologiaRESUMO
INTRODUCTION: Autologous tumor cell vaccines rely on the concept of preserving an individual's own tumorigenic makeup, expressing its unique set of tumor-associated antigens as well as antigenic elements from the surrounding stroma. These autologous tumor characteristics are usually presented with an immune adjuvant in the hopes of enhancing an immune response. METHODS: The autologous vaccine we used was composed of tumor cells combined with BCG and formalin. Animal safety and toxicity were evaluated using mice tumors for the immunotherapy. A small number of patients with advanced stage breast cancer were recruited for an uncontrolled study, using the vaccine solely or combined with chemotherapy/radiotherapy. RESULTS: The immunotherapy had shown to be safe in mice and humans. Upon a 5-year follow-up, the survival rate was 60 % for the combined treatment. CONCLUSIONS: The data suggest that the combined treatment could be a feasible and safe therapeutic strategy. However, further controlled studies should be conducted.
Assuntos
Adjuvantes Imunológicos/uso terapêutico , Neoplasias da Mama/terapia , Vacinas Anticâncer/uso terapêutico , Mycobacterium bovis/imunologia , Animais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/mortalidade , Vacinas Anticâncer/imunologia , Quimiorradioterapia , Cricetinae , Feminino , Cobaias , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Taxa de SobrevidaRESUMO
Glucocorticoids are known to play a role in the regulation of peripheral glucose mobilization and metabolism. Although several animal studies have shown that hippocampal glucose metabolism is reduced acutely and chronically by the action of corticosterone and that excess glucocorticoids are harmful to hippocampal neurons, little is known about the central effects of glucocorticoids in the human. In this study we examined the brain glucose utilization (CMRglu) response to hydrocortisone (cortisol) in seven normal elderly and eight Alzheimer's disease (AD) patients. On 2 separate days, immediately after the administration of a bolus of either 35 mg hydrocortisone or placebo, we administered 2-deoxy-2-[18F]fluoro-D-glucose. After a 35-min radiotracer uptake period, positron emission tomography (PET) images were collected. PET CMRglu images were analyzed using two methods: an image transformation that allowed analyses across cases on a voxel by voxel basis, and an anatomically based region of interest method that used coregistered magnetic resonance imaging scans. Both image analysis methods yielded similar results, identifying relative to placebo, a specific hippocampal CMRglu reduction in response to the hydrocortisone challenge that was restricted to the normal group. The region of interest technique showed CMRglu reductions of 16% and 12% in the right and left hippocampi, respectively. Blood collected during the PET scans showed, for the normal group, a rise in plasma glucose levels, starting approximately 25 min after hydrocortisone administration. The AD group did not show this effect. Baseline cortisol was elevated in the AD group, but the clearance of hydrocortisone was not different between the groups. In conclusion, these data show that among normal individuals in the presence of a pharmacological dose of cortisol, the glucose utilization of the hippocampus is specifically reduced, and serum glucose levels increase. Based in part on other studies, we offer the interpretation that glucocorticoid-mediated regulation of glucose transport is altered in AD, and this may underlie both the hippocampal insensitivity to cortisol and the failure in these patients to mount a peripheral glucose response. As our findings could reflect an altered state of the AD patients, we interpret our results as preliminary with respect to evidence for metabolic abnormalities in AD. The results suggest the continued study of the hydrocortisone challenge as a test of hippocampal responsivity.
Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Glucose/metabolismo , Hipocampo/metabolismo , Hidrocortisona/farmacologia , Idoso , Doença de Alzheimer/diagnóstico , Glicemia/análise , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Fluordesoxiglucose F18 , Humanos , Hidrocortisona/sangue , Imageamento por Ressonância Magnética , Masculino , Compostos Radiofarmacêuticos , Valores de Referência , Tomografia Computadorizada de EmissãoRESUMO
Twenty-one consecutive right-handed male psychiatric inpatients treated on a unit designed for the management of violent behavior were given computerized EEGs. We recorded their violent behaviors, the number of staff interventions needed to control their behavior, and their medications. The number of instances of violence as well as the number of staff interventions were related to increased delta band activity and to decreased alpha band activity in the temporal and the parietooccipital areas. These relationships were independent of the current medications and of the length of stay on the special unit. Furthermore, our results demonstrate that violence is very significantly related to the hemispheric asymmetry in EEG for the frontotemporal derivations. With increased levels of violence there was a greater level of delta power in the left compared with the right.
Assuntos
Eletroencefalografia , Transtornos Mentais/fisiopatologia , Violência , Adulto , Ritmo alfa , Ritmo Delta , Eletroencefalografia/métodos , Lateralidade Funcional , Humanos , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Análise de Regressão , Processamento de Sinais Assistido por ComputadorRESUMO
This double-blind, placebo-controlled study tested the effectiveness of tryptophan (TRP) in the treatment of aggressive psychiatric inpatients. After a baseline observation period of 1 month, patients were randomly assigned to treatment either with TRP (up to 6 g/day) or with placebo. There were 10 subjects in each treatment group. These treatments were administered for 25-35 days, after which the patients were observed for 1 month. Throughout this study, patients were receiving other medications. Injections of antipsychotics and sedatives were administered as needed to control agitated or violent behavior. Blood levels of TRP and other large neutral amino acids were obtained repeatedly, and ratios between TRP and other amino acids were computed. These analyses confirmed significant increases of TRP ratios in TRP-treated patients. TRP treatment had no effect on the number of violent incidents, but it significantly reduced the need for injections of antipsychotics and sedatives. The study thus provided indirect support for beneficial effects of TRP in aggressive psychiatric inpatients.
Assuntos
Agressão/psicologia , Hospitalização , Transtornos Mentais/tratamento farmacológico , Triptofano/administração & dosagem , Adulto , Antipsicóticos/administração & dosagem , Encéfalo/efeitos dos fármacos , Cacau , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Serotonina/efeitos dos fármacosRESUMO
Our goal was to ascertain the involvement of the temporal lobe in the preclinical (not yet diagnosable) stages of dementia of the Alzheimer's type (DAT) by using MRI-derived volumes. We assessed anatomical subdivisions of the temporal lobe on three groups of carefully screened age- and education-matched elderly individuals: 27 normal elderly (NL), 22 individuals with minimal cognitive impairment (MCI), who did not fulfill DAT criteria but were regarded at high risk for future DAT, and 27 DAT individuals. We found hippocampal volume reductions of 14% for the MCI and 22% for the DAT group compared to the NL group. Utilizing regression analyses and after accounting for gender head size-age, generalized atrophy (CSF), and other temporal lobe subvolumes, the hippocampal volume separated NL from MCI individuals, correctly classifying 74%. For NL and MCI groups combined the hippocampal volume was the only temporal lobe subvolume related to delayed recall memory performance. When contrasting MCI and DAT individuals, the fusiform gyrus volume uniquely improved the ability of the hippocampal volume to separate MCI from DAT individuals from 74 to 80%. Our cross-sectional data suggest that, within the temporal lobe, specific hippocampal volume reductions separated the group at risk for DAT from the normal group. By the time impairments are sufficient to allow a diagnosis of DAT to be made, in addition to the medial temporal lobe volume reductions, the lateral temporal lobe is also showing volume reductions, most saliently involving the fusiform gyrus.
Assuntos
Doença de Alzheimer/patologia , Hipocampo/patologia , Idoso , Doença de Alzheimer/psicologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/psicologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Variações Dependentes do Observador , Psicometria , Risco , Lobo Temporal/patologiaRESUMO
Our goal was to ascertain, among normal elderly and individuals with mild cognitive impairment, which temporal lobe neocortical regions predicted decline to dementia of the Alzheimer's type (DAT). Individuals received an MRI at baseline and a clinical and cognitive evaluation at baseline and follow-up. By using the baseline MRI we assessed the anatomical subdivisions of the temporal lobe: anteromedial temporal lobe (hippocampus and parahippocampal gyrus), medial occipitotemporal (fusiform) gyrus, middle and inferior temporal gyri, and superior temporal gyrus. We studied two groups of carefully screened age- and education-matched elderly individuals: 26 normal elderly (NL) and 20 individuals with mild cognitive impairment (MCI). Fourteen individuals (12 from the MCI group and two from the NL group) declined to DAT within the 3.2-year follow-up interval. We used logistic regression analyses to ascertain whether the baseline brain volumes were useful predictors of decline to DAT at follow-up after accounting for age, gender, individual differences in brain size, and other variables known to predict DAT. After accounting for age, gender, and head size, adding the volume of the anteromedial temporal lobe (the aggregate of hippocampus and parahippocampal gyrus) and an index of global atrophy raised the accuracy of overall classification to 80.4%. However, the ability to detect those individuals who declined (sensitivity) was low at 57%. When baseline medial occipitotemporal and the combined middle and inferior temporal gyri were added to the logistic model, the overall classification accuracy reached 95.6% and, most importantly, the sensitivity rose to 92.8%. These data indicate that the medial occipitotemporal and the combined middle and inferior temporal gyri may be the first temporal lobe neocortical sites affected in AD; atrophy in these areas may herald the presence of future AD among nondemented individuals. No other clinical baseline variables examined predicted decline with sensitivities above 71%. The apolipoprotein APOE epsilon4 genotype was not associated with decline.
Assuntos
Doença de Alzheimer/diagnóstico , Hipocampo/patologia , Giro Para-Hipocampal/patologia , Lobo Temporal/patologia , Fatores Etários , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Atrofia/etiologia , Atrofia/patologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Testes Neuropsicológicos , Índice de Gravidade de Doença , Fatores SexuaisRESUMO
We used MRI volume sampling with coregistered and atrophy corrected FDG-PET scans to test three hypotheses: 1) hippocampal formation measures are superior to temporal neocortical measures in the discrimination of normal (NL) and mild cognitive impairment (MCI); 2) neocortical measures are most useful in the separation of Alzheimer disease (AD) from NL or MCI; 3) measures of PET glucose metabolism (MRglu) have greater diagnostic sensitivity than MRI volume. Three groups of age, education, and gender matched NL, MCI, and AD subjects were studied. The results supported the hypotheses: 1) entorhinal cortex MRglu and hippocampal volume were most accurate in classifying NL and MCI; 2) both imaging modalities identified the temporal neocortex as best separating MCI and AD, whereas widespread changes accurately classified NL and AD; 3) In most between group comparisons regional MRglu measures were diagnostically superior to volume measures. These cross-sectional data show that in MCI hippocampal formation changes exist without significant neocortical changes. Neocortical changes best characterize AD. In both MCI and AD, metabolism reductions exceed volume losses.
Assuntos
Doença de Alzheimer/patologia , Transtornos Cognitivos/patologia , Glucose/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Atrofia , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de EmissãoRESUMO
We used CT and MR to examine the frequency of occurrence of hippocampal formation atrophy (HA) in a research clinic population of 130 normal elderly, 72 nondemented patients with very mild memory and cognitive impairments (MCI), 73 mild Alzheimer's disease (AD) patients, and 130 patients with moderate to severe AD. HA was found in 29% of the normal elderly group and its frequency of occurrence was strongly related to increasing age. For normal elderly 60-75 years of age, 15% had HA: the proportion rose to 48% in subjects 76-90 years of age. Among the three groups of impaired patients, the frequencies of HA ranged from 78% in the MCI patients to 96% in the advanced AD group. Unlike the normal elderly group, the percentages were not related to age. In both the normal elderly group and MCI group disproportionately more males than females had HA. After controlling for learning and the effects of generalized brain changes as reflected in ventricular size, only in the normal group was HA associated with reduced delayed verbal recall performance. Follow-up examinations for 15 individuals with baseline HA. 4 who at entry were MCI and 11 probable AD, yielded clinical and neuropathologic diagnoses of AD in all cases. The results of the present study indicate that hippocampal formation atrophy is associated with memory and cognitive impairments. Further longitudinal and neuropathologic work is required to validate the relationship between hippocampal formation atrophy and AD.
Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Hipocampo/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Atrofia , Ventrículos Cerebrais/patologia , Ventriculografia Cerebral , Estudos Transversais , Feminino , Lateralidade Funcional/fisiologia , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Psicometria , Caracteres Sexuais , Tomografia Computadorizada por Raios XRESUMO
Inpatient assaults were videotaped and then characterized by tape reviewers as showing high or low hostility. Over a 2-month period, the videotape reviewers documented more than twice as many high-hostility assaults as were documented by other methods of reporting.
Assuntos
Hospitalização , Transtornos Mentais/psicologia , Gravação de Videoteipe , Violência , Feminino , Hostilidade , Humanos , Masculino , Projetos PilotoRESUMO
This study relates violent behavior of schizophrenic inpatients to demographic, historical, EEG, neurological, and neuropsychological variables. Patients were classified into high (N = 28), low (N = 27), or no (N = 34) violence groups. There were no significant differences among the groups on demographic or historical variables, except for prevalence of violent crime, which was higher in both violent groups than in nonviolent patients. Neurological and neuropsychological abnormalities differentiated the groups, with the high violence group evidencing more abnormalities than the other two groups in the area of integrative sensory and motor functions. The authors suggest that violence as well as neurological and neuropsychological deficits may characterize a more severe form of schizophrenia.
Assuntos
Esquizofrenia/fisiopatologia , Violência , Adulto , Agressão , Eletroencefalografia , Família , Feminino , Humanos , Entrevista Psicológica , Masculino , Exame Neurológico , Testes Psicológicos , Psicologia do Esquizofrênico , Percepção VisualRESUMO
OBJECTIVE: The primary purpose of this study was to assess whether an interaction between subtle neurological impairment and haloperidol plasma level affects treatment response and, if so, the impact on negative symptoms in particular. METHOD: Forty-three schizophrenic and two schizoaffective inpatients diagnosed according to Research Diagnostic Criteria were given, at the end of a 1-week placebo period, a baseline evaluation consisting of the Brief Psychiatric Rating Scale (BPRS), Scales for the Assessment of Positive and Negative Symptoms, Quantified Neurological Scale, and the Simpson-Angus Scale for extrapyramidal side effects. Subjects were randomly assigned to one of three haloperidol plasma ranges and treated for 6 weeks. At the end point the BPRS, Scales for the Assessment of Positive and Negative Symptoms, and Simpson-Angus Scale were readministered. Multiple linear regressions were used to assess the extent to which the interaction between neurological abnormality and haloperidol plasma level predicted the end-point symptoms once the baseline symptoms, neurological abnormality, and haloperidol plasma level were accounted for. RESULTS: Those patients with higher levels of overall abnormality on the Quantified Neurological Scale at baseline and with frontal dysfunction in particular, had, with increasing haloperidol plasma levels, more severe negative symptoms at end point. Neurological dysfunction was not related to end-point positive symptoms. The effect was specific to end-point negative symptoms and was independent of extrapyramidal side effects. CONCLUSIONS: If confirmed, these findings may indicate that relatively intact frontal function is needed for improvement in negative symptoms and that those patients with schizophrenia who have subtle neurological dysfunction should be treated with lower doses of neuroleptics.
Assuntos
Haloperidol/uso terapêutico , Doenças do Sistema Nervoso/complicações , Esquizofrenia/tratamento farmacológico , Adulto , Estudos de Coortes , Comorbidade , Fatores de Confusão Epidemiológicos , Método Duplo-Cego , Feminino , Lobo Frontal/fisiopatologia , Haloperidol/sangue , Humanos , Masculino , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/fisiopatologia , Exame Neurológico , Placebos , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/complicações , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Esquizofrenia/complicações , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Resultado do TratamentoRESUMO
For 11 AD cases and four normal elderly controls, post mortem volumes of the hippocampal subdivisions were calculated by using magnetic resonance imaging and histological sections. After at least six weeks of fixation in formalin, brains were examined on a 1.5-T Philips Gyroscan imager producing T1-weighted coronal images with a 3-mm slice thickness. Brains were then processed and embedded in paraffin. Serial coronal sections, 3 mm apart and stained with Cresyl Violet, were used for the planimetry and unbiased estimation of the total numbers of neurons in the hippocampal subdivisions. For all 15 cases, magnetic resonance imaging- and histology-based measurements were performed along the whole rostrocaudal extent of the hippocampal formation and included three subvolumes: (i) the hippocampus (CA1-CA4 and the dentate gyrus); (ii) hippocampus/subiculum; and (iii) hippocampus/parahippocampal gyrus. After controlling for shrinkage, strong correlations were found between magnetic resonance imaging and histological measurements for the hippocampus (r = 0.97, P < 0.001), hippocampus/subiculum (r = 0.95, P < 0.001) and hippocampus/parahippocampal gyrus (r = 0.89, P < 0.001). We also calculated the total number of neurons in the hippocampus and hippocampus/subiculum subvolumes. Strong correlations between the magnetic resonance imaging subvolumes and neuronal counts were found for the hippocampus (r = 0.90, P < 0.001) and the hippocampus/subiculum subvolume (r = 0.84, P < 0.001). We conclude that very accurate volumetric measurements of the whole hippocampal formation can be obtained by using a magnetic resonance imaging protocol. Moreover, the strong correlations between magnetic resonance imaging-based hippocampal volumes and neuronal numbers suggest the anatomical validity of magnetic resonance imaging volume measurements.
Assuntos
Doença de Alzheimer/patologia , Hipocampo/patologia , Imageamento por Ressonância Magnética , Idoso , Cadáver , Contagem de Células , Humanos , Neurônios/patologia , Giro Para-Hipocampal/patologia , Valores de ReferênciaRESUMO
Nine young and 11 elderly men participated in this placebo-controlled, double-blind, crossover study (0.5 mg/kg cortisol or intravenous placebo). Participants learned a word list before cortisol administration, and delayed recall was then tested. A 2nd word list was learned and recalled after drug administration. In addition, the Paragraph Recall Test and tests measuring working memory (Digit Span), attention (timed cancellation), and response inhibition (Stroop Color and Word Test) were administered at 2 time points after drug administration. Cortisol reduced recall from the word list learned before treatment in both groups but did not influence recall of the list learned after treatment. In contrast, Digit Span performance was decreased by cortisol in young but not elderly participants. The possibility that differential age-associated brain changes might underlie the present results is discussed.
Assuntos
Hidrocortisona/análogos & derivados , Hidrocortisona/farmacologia , Rememoração Mental/efeitos dos fármacos , Aprendizagem Verbal/efeitos dos fármacos , Adulto , Fatores Etários , Idoso , Atenção/efeitos dos fármacos , Estudos Cross-Over , Aprendizagem por Discriminação/efeitos dos fármacos , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resolução de Problemas/efeitos dos fármacos , Retenção Psicológica/efeitos dos fármacos , Aprendizagem Seriada/efeitos dos fármacosRESUMO
Population trends indicate that in the near future the size of the elderly population will increase. This will result in a large increment in the numbers of persons suffering mild to severe levels of cognitive impairment. While considerable efforts continue to be made to explain brain changes associated with Alzheimer disease (AD), little is known of the brain changes in aging without dementia or so-called normal aging. Pathologic studies suggest that the medial temporal lobe is informative in the examination of the early brain changes related to AD. However, pathologic studies only offer a single observation and considerable uncertainty exists regarding the likelihood of progression of disease and the development of dementia. Several structural neuroimaging studies have recently investigated this anatomy and recent reports are encouraging for a medial temporal lobe based diagnosis for age-related cognitive impairments. We will present our findings on the MRI anatomy of the hippocampal formation as well as data bearing on the use of hippocampal formation imaging in the diagnosis of AD and as a predictive marker for future dementia. Our findings suggest an anatomically specific relationship between hippocampal volume and secondary memory performance. Because these observations apply to nondemented and normal elderly subjects, we are encouraged that the anatomy of age-related cognitive impairments can be reliably recognized and possibly put to use in therapeutic studies.
Assuntos
Envelhecimento/fisiologia , Doença de Alzheimer/diagnóstico , Hipocampo/patologia , Idoso , Atrofia , Estudos Transversais , Previsões , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Valores de Referência , Fatores de RiscoRESUMO
This study compared patients who showed persistent violence, transient violence and no violence. The presence of neurological abnormalities was found to be the factor that differentiated most clearly among the three groups. The persistently violent patients, in addition to showing significantly more neurological abnormalities, also evidenced a more disturbed family background. Both violent groups had a higher incidence of violent crime prior to hospitalization than the nonviolent controls. A logistic regression model simultaneously relating the effects of six factors on violent behavior was developed and used to predict violent group membership.
Assuntos
Hospitalização , Transtornos Mentais/psicologia , Violência , Adulto , Fatores Etários , Crime , Eletroencefalografia , Família , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Transtornos Mentais/genética , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/prevenção & controle , Controle Social FormalRESUMO
Cross-sectional cerebrospinal fluid (CSF) levels of tau and amyloid (A) beta (beta) are of diagnostic importance for Alzheimer's disease (AD) and mild cognitive impairment (MCI). However, most longitudinal studies of tau fail to demonstrate progression. Because predominantly brain-derived proteins such as tau, have higher ventricle to lumbar ratios, we hypothesized that adjusting for the ventricular enlargement of AD would correct for the dilution of tau, and improve detection of longitudinal change. Abeta which is not exclusively brain derived, shows a ratio <1, and no benefit was expected from adjustment. In a 1 year longitudinal study of eight MCI and ten controls, we examined CSF levels of hyperphosphorylated (P) tau231, Abeta40, and Abeta42. In cross-section, MCI patients showed elevated Ptau231 and Abeta40 levels, and greater ventricular volumes. Longitudinally, only after adjusting for the ventricular volume and only for Ptau231, were increases seen in MCI. Further studies are warranted on mechanisms of tau clearance and on using imaging to interpret CSF studies.
Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Transtornos Cognitivos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Idoso , Biomarcadores , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Valores de Referência , Índice de Gravidade de Doença , Estatísticas não ParamétricasRESUMO
PURPOSE: To test the hypothesis that atrophy of the hippocampal formation in nondemented elderly individuals would predict subsequent Alzheimer disease. METHOD: We studied 86 subjects at two time points, 4 years apart. At baseline all study subjects were nondemented and included 54 control subjects and 32 persons who had memory complaints and minimal cognitive impairments. All subjects received a CT scan using a protocol designed to image the perihippocampal cerebrospinal fluid (HCSF) accumulating in the fissures along the axis of the hippocampal formation. Blind to the clinical evaluations, we subjectively assessed the presence of HCSF at the baseline. Retrospectively, we examined the predicted association between baseline HCSF and clinical decline as determined across the two evaluations. RESULTS: At follow-up 25 of the 86 subjects had deteriorated and received the diagnosis of Alzheimer disease. Of the declining subjects, 23 came from the minimally impaired group, and 2 came from the control group. In the minimally impaired group the baseline HCSF measure had a sensitivity of 91% and a specificity of 89% as a predictor of decline. Both control subjects who deteriorated were also correctly identified at baseline. One of these two subjects died, and an autopsy confirmed the presence of Alzheimer disease. M(r) validation studies demonstrated that HCSF is quantitatively related to dilatation of the transverse fissure of Bichat and the choroidal and hippocampal fissures. CONCLUSION: Our findings strongly suggest that among persons with mild memory impairments, dilatation of the perihippocampal fissures is a useful radiologic marker for identifying the early features of Alzheimer disease.