RESUMO
The early diagnosis and excision of cutaneous melanoma is essential for an improved prognosis of the disease. Besides the investigation of pigmented lesions with the unaided eye and conventional dermatoscopy, long-term sequential digital dermatoscopy has been shown to improve the sensitivity of melanoma detection, especially in high-risk patients. In addition to the static clinical and dermatoscopic assessment, the sequential digital dermatoscopy strategy helps to detect changes over time. This review summarizes the latest developments in the field of sequential digital dermatoscopy, describes current strategies for the selection of patients and lesions to monitor, and suggests objective criteria that should lead to an excisional biopsy.
Assuntos
Dermoscopia/métodos , Detecção Precoce de Câncer/métodos , Interpretação de Imagem Assistida por Computador/métodos , Melanoma/patologia , Processamento de Sinais Assistido por Computador , Neoplasias Cutâneas/patologia , Técnica de Subtração , HumanosRESUMO
The accumulation of beta-amyloid (A beta) plaques and neurofibrillary tangles consisting of hyperphosphorylated tau protein are pathological features of Alzheimer's disease (AD) commonly modeled in mice using known human familial mutations; however, the loss of neurons also found to occur in AD is rarely observed in such models. The mechanism of neuron degeneration remains unclear but is of great interest as it is very likely an important factor for the onset of adverse memory deficits occurring in individuals with AD. The role of A beta in the neuronal degeneration is a matter of controversial debates. In the present study we investigated the impact of extracellular plaque A beta versus intraneuronal A beta on neuronal cell death. The thalamus and the frontal cortex of the APP/PS1KI mouse model were chosen for stereological quantification representing regions with plaques only (thalamus) or plaques as well as intraneuronal A beta (frontal cortex). A loss of neurons was found in the frontal cortex at the age of 6 months coinciding with the decrease of intraneuronal immunoreactivity, suggesting that the neurons with early intraneuronal A beta accumulation were lost. Strikingly, no neuron loss was observed in the thalamus despite the development of abundant plaque pathology with levels comparable to the frontal cortex. This study suggests that plaques have no effect on neuron death whereas accumulation of intraneuronal A beta may be an early transient pathological event leading to neuron loss in AD.
