Fulminant Lewy body disease.

The clinical distinction between Parkinson's disease (PD) with dementia (PDD) and dementia with Lewy bodies (DLB) is challenged by most neuropathological studies showing nearly identical changes in both conditions. We report an unusual case of PD evolving into a rapidly progressive dementia leading to death within 3 months that showed nearly all clinical features of DLB. At autopsy, numerous Lewy bodies and Lewy neurites were found in several areas of the brainstem, the limbic system, and the neocortex, consistent with pure DLB. This case demonstrates that Lewy body disease may exhibit a dramatic course without any coexisting pathology and exemplifies that PD, PDD, and DLB may sometimes represent sequential, yet overlapping, phenotypes of a same clinicopathological entity.

Evaluation of pig esophageal mucosa as a permeability barrier model for buccal tissue.

Porcine buccal mucosa is frequently used for in vitro drug absorption studies as its structure and permeability characteristics are close to those of human tissue. However, this tissue model suffers from practical disadvantages, including a limited surface area, damage caused by mastication, and a fastidious and time-consuming excision procedure. It has been hypothesized that such limitations may be overcome by replacing the buccal tissue with the pig esophageal mucosa. The latter has a very similar structure and is easier to separate from the underlying tissue; furthermore, its surface area is greater and is generally intact. The aims of this work, therefore, were (i) to perform histological studies on the two membranes; (ii) to compare the transport of fentanyl citrate across buccal and esophageal mucosae; and (iii) to evaluate the effects of freezing on the tissue permeability. The results show that their histology is comparable, that the permeability of fentanyl citrate across the two epithelial barriers is similar, and that freezing the tissues did not alter their permeability.

Comparison of the lipid composition of porcine buccal and esophageal permeability barriers.

Pig esophageal mucosa has been shown to be a useful and practical substitute for buccal mucosa in in vitro permeability studies in that it offers a larger surface area and it is much easier to prepare. Further, the tissues demonstrate similar histological characteristics. The objectives of this work were to characterize the lipid composition of the esophageal mucosa, to compare it to that of the buccal tissue, and to correlate lipid composition with the membranes' permeability to fentanyl. The major lipid classes of buccal and esophageal epithelia were separated and analysed by automated multiple development high-performance thin-layer chromatography (AMD-HPTLC). The two epithelia presented a very similar lipid pattern. In general, there were more polar lipids than non-polar; glycosylceramides were relatively abundant whereas the amount of ceramides present was very small. The flux of fentanyl applied as the citrate in aqueous solution was comparable across the buccal and esophageal barriers. Lipid extraction provoked a significant increase in permeability. In conclusion, this research confirms the suitability of the esophageal mucosa as a model for buccal permeability studies.

[How should a muscular disease be studied?]. / Comment investiguer une maladie musculaire?

Muscle diseases are an expanding field, mainly due to the progress in genetics and biochemistry. Evaluation starts with a thorough history of the patient's symptoms and signs. The leading clinical manifestations are weakness, atrophy, myalgia, fatigue, more rarely myotonia and in the child hypotonia or walking difficulty. A detailed family history might give clues to an underlying genetic etiology. Diagnostic workup begins with the measurement of serum creatine kinase. Electroneuromyography is an important investigation procedure which includes motor and sensory nerve conduction studies and concentric needle electromyography. Muscle biopsy is performed in all patients with clinical evidence of myopathy. A fine-needle technique is generally used, more often than a surgical biopsy. Molecular analysis of candidate genes is becoming a major diagnostic tool in many muscle disorders. Muscle imaging, in particular MR, provides diagnostic and follow-up information, especially in dystrophic, metabolic and inflammatory myopathies. Exercise testing can be useful in some metabolic myopathies. There is no standard protocol for the choice and course of investigations which must always be based on a detailed clinical evaluation. It is important to establish a precise diagnosis in order to inform the patient about the nature and the evolution of the disease, the therapeutic options and to propose, when indicated, genetic counseling.