Amyotrophic lateral sclerosis (ALS), Charcot’s disease or Lou Gehrig’s disease, is a term used to cover the spetrum of syndromes caracterized by progressive degeneration of motor neurons, a paralytic disorder caused by motor neuron degeneration. Currently, there are approximately 25,000 patients with ALS in the USA, with an average age of onset of 55 years. The incidence and prevalence of ALS are 1-2 and 4-6 per 100,000 each year, respectively, with a lifetime ALS risk of 1/600 to 1/1000. It causes progressive and cumulative physical disabilities, and leads to eventual death due to respiratory muscle failure. ALS is diverse in its presentation, course, and progression. We do not yet fully understand the causes of the disease, nor the mechanisms for its progression; thus, we lack effective means for treating this disease. In this chapter, we will discuss the diagnosis, treatment, and how to cope with impaired function and end of life based on of our experience, guidelines, and clinical trials. Nowadays ALS seems to be a more complex disease than it did two decades – or even one decade – ago, but new insights have been plentiful. Clinical trials should be seen more as experiments on pathogenic mechanisms. A medication or combination of medications that targets more than one pathogenic pathway may slow disease progression in an additive or synergistic fashion.
Oviducal gland present in elasmobranchs is correlated to the organism's reproductive strategy, and its functions are to produce mucus, to form the egg's tertiary envelope and to store sperm. The gland contains four zones: club, papillary, baffle and terminal. The structures of the oviduct, oviducal gland and isthmus of blue shark Prionace glauca were described using macroscopic, light microscopy and scanning electron microscopy techniques. The epithelium of the oviduct and isthmus is folded and is a simple, columnar, ciliated lining epithelium with glandular cells. In the oviducal gland, the lining tissues in the four zones are similar to the oviduct and isthmus lining. The terminal zone shows the presence of sperm in the lumen of the secretory tubules, which remains stored even in the absence of recent copulation. Here, these organs were studied and their connections in an attempt to elucidate the mechanisms of reproduction in the blue shark, showing the three-dimensional aspects, thus adding morphological information important for the understanding of the structure and functioning of these organs of fundamental importance in the life of the majority of elasmobranchs.A glândula oviducal presente nos elasmobrânquios está correlacionada com a estratégia reprodutiva, cuja função é de produzir o muco, formar o envelope terciário do ovo e armazenar espermatozóides. A glândula contém quatro zonas: club, papilar, baffle e terminal. Foi descrita a estrutura do oviduto, glândula oviducal e istmo do tubarão-azul, Prionace glauca, pelas técnicas macroscópica, microscópica de luz e eletrônica de varredura. Foi observado que no oviduto e istmo o epitélio é pregueado de revestimento simples, colunar, ciliado com células glandulares. Na glândula oviducal o tecido de revestimento é semelhante ao oviduto e istmo nas quatro zonas. Na zona terminal observou-se a presença de espermatozoides no lúmen dos túbulos secretores que permanecem estocados mesmo na ausência de copula recente. Aqui, estudaram-se esses órgãos e suas conexões na tentativa de elucidar os mecanismos da reprodução no tubarão azul, apresentando os aspectos tridimensionais, desta forma agregando informações morfológicas importantes para o entendimento da estrutura e funcionamento desses órgãos de fundamental importância na vida da maioria dos elasmobrânquios.
Imparfinis mishky (Siluriformes, Heptapteridae) a new species from the rios Parana and Uruguay basins in Argentina. -Imparfinis mishky sp. n. is described from the rio Parana and rio Uruguay basins in Argentina. Imparfinis mishky sp. n. is distinguished from other species of the genus by the following combination of characters: pectoral-fin spine with smooth anterior and posterior margins; caudal fin deeply forked with dorsal lobe longer than ventral lobe; adipose fin not reaching caudal fin; body with six dark saddles across the dorsum, and without a mid-lateral band. It was found inhabiting well oxygenated, neutral pH, flowing waters, with sandy or cobble covered bottom.
The oral denticles of some elasmobranchs are found on the surface of the oral cavity and are homologous to those on the body surface, being well developed, independent and non-growing, with varying morphology and distribution depending on the species. The structural and three-dimensional characteristics of oral denticles from the rostro-ventral surface of the sharpnose shark Rhizoprionodon lalandii were described following imaging by both light and scanning electron microscopy. The light microscopy results showed that the triangular shape of the denticles consisted of a base and an apex. Picrosirius staining showed the arrangement of collagen fibres and oral denticles, and a predominance of type-I collagen was found in both structures under polarized light. There was a broad homogeneous distribution of denticles on the ventral surface, forming a leaf-like shape with the cusp facing the caudal region. Interlocking, hexagonal, geometric structures on its rostral side and ridges on the rostral side of the oral denticles were observed under increased magnification. We concluded that the denticle morphology found in R. lalandii differ of others analysed species, and the descriptions of these structures therefore provide important information for the classification of the species. In this species, the main functions can be assigned to help reduce hydrodynamic drag, particularly by this being a species that uses ram ventilation, and to protect the epithelium of the oropharynx of abrasion and parasites.
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