Pathological Subtypes (pathological + subtype)

Distribution by Scientific Domains


Selected Abstracts


Fibromuscular dysplasia of cervical and intracranial arteries

INTERNATIONAL JOURNAL OF STROKE, Issue 4 2010
Emmanuel Touzé
Fibromuscular dysplasia is an uncommon, segmental, nonatherosclerotic arterial disease of unknown aetiology. The disease primarily affects women and involves intermediate-sized arteries in many areas of the body, including cervical and intracranial arteries. Although often asymptomatic, fibromuscular dysplasia can also be associated with spontaneous dissection, severe stenosis that compromises the distal circulation, or intracranial aneurysm, and is therefore responsible for cerebral ischaemia or subarachnoid haemorrhage. Fibromuscular dysplasia affects middle and distal portions of the internal carotid and vertebral arteries, and occasionally, intracranial arteries. Several pathological and angiographic patterns exist. The most frequent pathological type is medial fibromuscular dysplasia, which is associated with the ,string of beads' angiographic pattern. Unifocal lesions are less common and can be associated with several pathological subtypes. The pathophysiology of the disease is widely unknown. Fibromuscular dysplasia may in fact result from various causes and reflect a non-specific response to different insults. The poor knowledge of the natural history and the lack of randomised trials that compared the different treatment options do not allow any satisfactory judgement to be made regarding the need for or the efficacy of any treatment. [source]


Role of radiology in the treatment of malignant hilar biliary strictures 1: Review of the literature

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 1 2004
Michael WJ Hii
SUMMARY Malignant strictures of the biliary tree are an uncommon cause of obstructive jaundice. There are a number of pathological subtypes, but tumours in this region tend to have similar clinical and diagnostic features and therapeutic and prognostic implications. We review the published literature on this topic discussing diagnostic modalities and treatment options with a focus on radiological intervention. Diagnosis currently is best achieved using a range of procedures. Direct cholangiography remains the gold standard in delineating anatomy, but the invasiveness of this procedure limits its use as a purely diagnostic tool. Magnetic resonance technology, in particular magnetic resonance cholangiopancreatography, has an increasing role as accessibility is improved. Treatment of these tumours is difficult. Surgical resection and palliative biliary enteric bypass are the most common methods used with endoscopic and percutaneous therapies reserved for palliating patients not fit for surgery. There is little firm evidence to suggest that any one palliative modality is superior. Interventional radiology is particularly suitable for palliative management of difficult and expansive lesions as the anatomy can preclude easy access by surgical or endoscopic techniques. Good palliative results with minimal mortality and morbidity can be achieved with percutaneous stenting . [source]


Phosphorylated and cleaved TDP-43 in ALS, FTLD and other neurodegenerative disorders and in cellular models of TDP-43 proteinopathy

NEUROPATHOLOGY, Issue 2 2010
Tetsuaki Arai
Transactivation response (TAR) DNA-binding protein of Mr 43 kDa (TDP-43) is a major component of the tau-negative and ubiquitin-positive inclusions that characterize amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration which is now referred to as FTLD-TDP. Concurrent TDP-43 pathology has been reported in a variety of other neurodegenerative disorders such as Alzheimer's disease, forming a group of TDP-43 proteinopathy. Accumulated TDP-43 is characterized by phosphorylation and fragmentation. There is a close relationship between the pathological subtypes of FTLD-TDP and the immunoblot pattern of the C-terminal fragments of phosphorylated TDP-43. These results suggest that proteolytic processing of accumulated TDP-43 may play an important role for the pathological process. In cultured cells, transfected C-terminal fragments of TDP-43 are more prone to form aggregates than full-length TDP-43. Transfecting the C-terminal fragment of TDP-43 harboring pathogenic mutations of TDP-43 gene identified in familial and sporadic ALS cases into cells enhanced the aggregate formation. Furthermore, we found that methylene blue and dimebon inhibit aggregation of TDP-43 in these cellular models. Understanding the mechanism of phosphorylation and truncation of TDP-43 and aggregate formation may be crucial for clarifying the pathogenesis of TDP-43 proteinopathy and for developing useful therapeutics. [source]


Early frontotemporal dementia targets neurons unique to apes and humans

ANNALS OF NEUROLOGY, Issue 6 2006
William W. Seeley MD
Objective Frontotemporal dementia (FTD) is a neurodegenerative disease that erodes uniquely human aspects of social behavior and emotion. The illness features a characteristic pattern of early injury to anterior cingulate and frontoinsular cortex. These regions, though often considered ancient in phylogeny, are the exclusive homes to the von Economo neuron (VEN), a large bipolar projection neuron found only in great apes and humans. Despite progress toward understanding the genetic and molecular bases of FTD, no class of selectively vulnerable neurons has been identified. Methods Using unbiased stereology, we quantified anterior cingulate VENs and neighboring Layer 5 neurons in FTD (n = 7), Alzheimer's disease (n = 5), and age-matched nonneurological control subjects (n = 7). Neuronal morphology and immunohistochemical staining patterns provided further information about VEN susceptibility. Results FTD was associated with early, severe, and selective VEN losses, including a 74% reduction in VENs per section compared with control subjects. VEN dropout was not attributable to general neuronal loss and was seen across FTD pathological subtypes. Surviving VENs were often dysmorphic, with pathological tau protein accumulation in Pick's disease. In contrast, patients with Alzheimer's disease showed normal VEN counts and morphology despite extensive local neurofibrillary pathology. Interpretation VEN loss links FTD to its signature regional pattern. The findings suggest a new framework for understanding how evolution may have rendered the human brain vulnerable to specific forms of degenerative illness. Ann Neurol 2006;60:660,667 [source]