Connecting genomic and proteomic signatures of amyloid burden in the brain.

Background: Alzheimer's disease (AD) has a high heritable component characteristic of complex diseases, yet many of the genetic risk factors remain unknown. We combined genome-wide association studies (GWAS) on amyloid endophenotypes measured in cerebrospinal fluid (CSF) and positron emission tomography (PET) as surrogates of amyloid pathology, which may be helpful to understand the underlying biology of the disease.

Methods: We performed a meta-analysis of GWAS of CSF Aβ42 and PET measures combining six independent cohorts (n=2,076).

Automated Classification of Cognitive Decline and Probable Alzheimer's Dementia Across Multiple Speech and Language Domains.

Background: Decline in language has emerged as a new potential biomarker for the early detection of Alzheimer's disease (AD). It remains unclear how sensitive language measures are across different tasks, language domains, and languages, and to what extent changes can be reliably detected in early stages such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI).

Method: Using a scene construction task for speech elicitation in a new Spanish/Catalan speaking cohort ( = 119), we automatically extracted features across seven domains, three acoustic (spectral, cepstral, and voice quality), one prosodic, and three from text (morpholexical, semantic, and syntactic).

Interaction of neuropsychiatric symptoms with APOE ε4 and conversion to dementia in MCI patients in a Memory Clinic.

To date, very few studies have been focused on the impact of the convergence of neuropsychiatric symptoms (NPS) and APOE ε4 on the conversion to dementia in patients with Mild Cognitive Impairment patients (MCI), and none has been based in a clinical setting. The objective of the study is to determine the predictive value of additive and multiplicative interactions of NPS and APOE ε4 status on the prediction of incident dementia among MCI patients monitored in a Memory Clinic. 1512 patients (aged 60 and older) with prevalent MCI were followed for a mean of 2 years.

The H1 Haplotype Is a Risk Factor for Alzheimer's Disease in ε4 Non-carriers.

An ancestral inversion of 900 kb on chromosome 17q21, which includes the microtubule-associated protein tau () gene, defines two haplotype clades in Caucasians (H1 and H2). The H1 haplotype has been linked inconsistently with AD. In a previous study, we showed that an SNP tagging this haplotype (rs1800547) was associated with AD risk in a large population from the Dementia Genetics Spanish Consortium (DEGESCO) including 4435 cases and 6147 controls.

Differentiated clinical presentation of early and late-onset Alzheimer's disease: is 65 years of age providing a reliable threshold?

Early-onset and late-onset Alzheimer's disease (EOAD and LOAD) are two forms of the disease with the same characteristic neuropathological hallmarks. However, higher burdens of neuritic plaques and neurofibrillary tangles in frontal and parietal lobes have been found in EOAD than in LOAD patients. Thus, the EOAD subjects may have a differentiated clinical presentation compared to the LOAD ones.

Item analysis of three Spanish naming tests: a cross-cultural investigation.

Neuropsychological evaluations conducted in the United States and abroad commonly include the use of tests translated from English to Spanish. The use of translated naming tests for evaluating predominately Spanish-speakers has recently been challenged on the grounds that translating test items may compromise a test's construct validity. The Texas Spanish Naming Test (TNT) has been developed in Spanish specifically for use with Spanish-speakers; however, it is unlikely patients from diverse Spanish-speaking geographical regions will perform uniformly on a naming test.

Detection of visuoperceptual deficits in preclinical and mild Alzheimer's disease.

Exhaustive neuropsychological assessment of mild cognitive impairment (MCI) subjects frequently identifies cognitive deficits other than memory. However, visuoperception has rarely been investigated in MCI. The 15-Objects Test (15-OT), a visual discrimination task based on the Poppelreuter Test, consists of 15 overlapping objects.

Comparative cognitive effects of bilateral subthalamic stimulation and subcutaneous continuous infusion of apomorphine in Parkinson's disease.

Bilateral subthalamic deep brain stimulation (STN-DBS) and continuous subcutaneous infusion of apomorphine (APM-csi) can provide a comparable improvement on motor function in patients with advanced Parkinson's disease (PD), but the mechanisms by which both therapies exert their effects are different. We analyzed the cognitive effects of APM-csi. We also compared neuropsychological effects induced by STN-DBS and APM-csi in advanced PD to ascertain the neuropsychological aspects relevant in determining the therapeutic procedure that is the most appropriate in a particular patient.

Cognitive effects of unilateral posteroventral pallidotomy: a 4-year follow-up study.

We assessed the long-term neuropsychological effects of unilateral posteroventral pallidotomy in Parkinson's disease. Eleven Parkinson's disease patients, from an original cohort of 15 consecutive patients who underwent pallidotomy, were evaluated. A neuropsychological battery was administered to each patient before (3 days) and after (3 months and 4 years) surgery during the effects of levodopa.