During the development of in vivo amyloid imaging agents, an effort was made to use micro-positron emission tomography (PET) imaging in the presenilin-1 (PS1)/amyloid precursor protein (APP) transgenic mouse model of CNS amyloid deposition to screen new compounds and further study Pittsburgh Compound-B (PIB), a PET tracer that has been shown to be retained well in amyloid-containing areas of Al...

Stepwise fibrillation of proteins to amyloid structures and amyloid-like protein aggregates occurs naturally or is disease associated. The hallmark of amyloid aggregation is conversion of otherwise soluble proteins into β-sheet conformations that locate extracellularly, in the cytoplasm or in the cell nucleus. Formation of amyloid-like protein aggregates unifies superficially unrelated human co...

A characteristic feature of Alzheimer's disease (AD) is the formation of amyloid plaques in the brain. Although this hallmark pathology has been well described, the biological effects of plaques are poorly understood. To study the effect of amyloid plaques on axons and neuronal connectivity, we have examined the axonal projections from the entorhinal cortex in aged amyloid precursor protein (AP...

The soluble fraction of brain samples from patients with Alzheimer's disease contains highly biologically active amyloid-β seeds. In this study, we sought to assess the potency of soluble amyloid-β seeds derived from the brain and cerebrospinal fluid. Soluble Alzheimer's disease brain extracts were serially diluted and then injected into the hippocampus of young, APP transgenic mice. Eight mont...

The degenerative process of Alzheimer's disease is linked to a shift in the balance between amyloid-beta (Abeta) production, clearance, and degradation. Neprilysin has recently been implicated as a major extracellular Abeta degrading enzyme in the brain. However, there has been no direct demonstration that neprilysin antagonizes the deposition of amyloid-beta in vivo. To address this issue, a l...

There is ample genetic, biochemical, cellular and molecular evidence to show that the amyloid peptide (A ), a proteolytic fragment of the amyloid precursor protein (APP), plays an important, if not causative role in Alzheimer’s disease (AD). An additional hallmark of AD is the neuroinflammatory response that is associated with the amyloid deposition. We discovered that the acute phase protein 1...

Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) is found in 30%-50% of individuals with HIV infection. To date, no HIV+ individual has been reported to have a positive amyloid PET scan. We report a 71-year-old HIV+ individual with HAND. Clinical and neuropsychologic evaluations confirmed a progressive mild dementia. A routine brain MRI was normal for age. [18F]Fluor...

Amyloid is a systemic disease characterized by extracellular deposition of misfolded protein. Gastrointestinal and peritoneal light chain (AL) amyloid an under-recognized manifestation this disease, usually as late sequela. Here we present case recently diagnosed AL that presented in the context recurrent, acute onset abdominal discomfort was found to have bowel obstruction complicated perforat...

BACKGROUND Amyloidosis is a rare complication of non-Hodgkin's lymphoma. Most of the reported patients have had systemic amyloidosis and have died as a result of complications of this disease. MATERIALS AND METHODS The clinical cases of two patients with lymphoplasmacytic non-Hodgkin's lymphoma who presented with lymphadenopathy due to localised amyloid deposition are reviewed. Immunohistoche...

Amyloid imaging represents a major advance in neuroscience, enabling the detection and quantification of pathologic protein aggregations in the brain. In this review we survey current amyloid imaging techniques, focusing on positron emission tomography (PET) with (11)carbon-labelled Pittsburgh Compound-B ((11)C-PIB), the most extensively studied and best validated tracer. PIB binds specifically...