Mucoepidermoid carcinoma of the lung in a 6-year-old boy

Primary malignant lung tumours, especially the mucoepidermoid cancer of the bronchus, are very uncommon in childhood. Obtaining the diagnosis might be difficult due to unspecific initial symptoms but early detection and treatment is crucial for a good long-term survival. Bronchoscopy is considered the “gold standard” for making the diagnosis. The recommended therapy for a mucoepidermoid lung cancer is sleeve lobectomy with favourable overall survival after complete resection. We report the case of a 6-year-old boy with a right-upper-lobe bronchus tumour. The histological examination revealed a lowgrade mucoepidermoid carcinoma.Key words: Endobronchial tumour, mucoepidermoid carcinoma, sleeve resectio

Pathology Case Study: Sellar / Suprasellar Mass

This is a case study presented by the University of Pittsburgh Department of Pathology in which a woman noticed a deterioration of vision and movement in her right eye over the course of four weeks. Visitors can view the neuropathological findings, and have the opportunity to diagnose the patient. This is an excellent resource for students in the health sciences to familiarize themselves with using patient history and laboratory results to diagnose disease. It is also a helpful site for educators to introduce or test students of neuropathology

Cerebrovascular P-glycoprotein expression is decreased in Creutzfeldt-Jakob disease.

The abnormal conformation and assembly of proteins in the central nervous system is increasingly thought to be a critical pathogenic mechanism in neurodegenerative disorders such as Creutzfeldt-Jakob disease (CJD) and Alzheimer's disease (AD). CJD is marked primarily by the buildup of misfolded prion protein (PrP(Sc)) in brain, whereas the accrual of beta-amyloid protein (Abeta) and tau protein are characteristic for AD. Prior studies have shown that the ATP-binding cassette transporter P-glycoprotein (P-gp) is a cellular efflux pump for Abeta, and that age-associated deficits in P-gp may be involved in the pathogenesis of Alzheimer's disease. In the present study, we investigated the relationship between P-gp and idiopathic CJD, and found that CJD, like AD, is associated with a decrease in the expression of cerebrovascular P-gp. In some instances, Abeta and PrP deposits coexist in cases of CJD, suggesting the possibility of pathogenic interactions. Since there is, to date, no evidence that PrP itself is a substrate for P-gp, we hypothesize that the age-related deficits in P-gp could promote the accumulation of PrP(Sc) either by promoting the buildup of Abeta (which could act as a seed for the aggregation of PrP(Sc)), or by overloading the ubiquitin-proteasomal catabolic system, and thereby facilitating the accumulation of PrP. Alternatively, the loss of P-gp could be a non-specific response to neurodegenerative changes in the central nervous system. In either case, dysfunction of this critical toxin-elimination pathway in CJD and AD suggests that selectively increasing cerebrovascular P-gp function could open new therapeutic pathways for the prevention and/or treatment of a number of proteopathic disorders of the central nervous system

Cerebral ß-amyloid angiopathy in aged squirrel monkeys

Cerebral ß-amyloid angiopathy (CAA) is an age-related disorder of the brain vasculature that is involved in up to 20% of non-traumatic cerebral hemorrhage in humans. CAA is a risk factor for cognitive decline, and may exacerbate the dementia of Alzheimer's disease. Progress in discovering the cause and potential therapies for this disorder has been hindered by the paucity of animal models, particularly models of idiopathic CAA. The squirrel monkey (Saimiri spp) develops significant CAA in the natural course of aging. To evaluate the suitability of Saimiri as a model of human CAA, we studied the distribution and composition of Aß subtypes in CAA and parenchymal (senile plaque) deposits in the brains of aged squirrel monkeys, as well as the relationship between vascular ßamyloid deposition and comorbid vasculopathies that occur in aged humans. Our findings show that: 1) CAA consists ultrastructurally of classical amyloid fibrils and is the principal type of cerebral ß-amyloidosis in squirrel monkeys; 2) The two primary isoforms of Aß (Aß40 and Aß42) coexist in most microvascular and parenchymal lesions of Saimiri, although Aß40 tends to predominate in larger arterioles; 3) CAA and parenchymal plaques overlap to a considerable degree in most affected brain areas, and are distributed symmetrically in the two hemispheres; 4) Both CAA and plaques are particularly abundant in rostral regions and comparatively sparse in the occipital lobe; 5) Capillaries are especially vulnerable to CAA in squirrel monkeys; and 6) When CAA is severe, it is associated with a small, but significant, increase in other vasculopathies, including microhemorrhage, fibrinoid extravasation and focal gliosis. These findings, in the context of genetic, vascular and immunologic similarities between squirrel monkeys and humans, support the squirrel monkey as a biologically advantageous model for studying the basic biology of idiopathic, age-related CAA, and for testing emerging therapies for human ß-amyloidoses such as Alzheimer's disease

Childhood onset mitochondrial myopathy and lactic acidosis caused by a stop mutation in the mitochondrial cytochrome c oxidase III gene

No abstract