The innervation pattern of skeletal muscles was studied in the normal and regenerating tail of Notophthalmus viridescens. Silver staining for nerve endings and histochemical localization of ...acetylcholinesterase (AChE) were used for light microscopy. In In normal musculature, AChE positive reactions were localized at the ends of the muscle fibers where they are anchored on connective tissue septa by myotendinous junctions. At this level, silver staining shows nerve terminals forming endplates. During regeneration, positive reactions for AChE appear de novo as dense plates localized at the ends of the newly formed myotubes. The mechanisms involved in the localization of AChE on this surface seem to operate before previous local contacts by nerve terminals. From the ultrastructural data and immunohistochemical results with anti-laminin antibody, these observations suggest that regenerating muscle fibers determine a region of post-synaptic specialization in close relation with the organization of myotendinous regions and basement membrane formation. Nerve-muscle contacts appear at these levels at stage IV (15-20 days after amputation) in the stump and in the rostral part of the regenerate (transition zone). These nerve terminals are provided by the disorganized peripheral nervous system of the injured segment. In the regenerate a similar pattern of AChE reaction can be seen in every myotube, differentiating according to a rostro-caudal gradient. Innervation at the ends of the muscle fibers is in spatiotemporal relation with the exists of the ventral roots from the regenerating nerve cord as the regenerate continues to grow in length.
The evolution of acute respiratory failure was studied in 27 patients with generalized peritonitis. The natural history of pulmonary failure indicates an incidence of 74% of atelectasis progressing ...to pneumonitis in the majority of patients. In 21 patients, similar aerobic microorganisms were recovered from the sputum and abdominal focus of infection. The emergence of gram negative pneumonia by the third day of onset of peritonitis appeared to add significantly to respiratory failure. In the management of respiratory failure, early use of positive and expiratory pressure with mechanical ventilation was associated with improvement or reversal of hypoxia. A high fatality (89%) was attributed to uncontrolled sepsis rather than to respiratory failure.
The Fund Director's Guidebook is intended for use by directors of investment companies registered under the Investment Company Act of 1940. The Guidebook summarizes or incorporates relevant ...information from the Corporate Director's guidebook and supplements that information with specific guidance on matters arising under the 1940 Act and other applicable law. The text of the guidebook is presented.
PDF
