Role of surgery in the treatment of severe acute necrotic pancreatitis

Between May 1975 and December 1991, a total of 208 patients were operated upon for severe acute necrotic pancreatitis. The decision whether to operate on patients with clinical and biologic aggravation despite particularly sustained intensive care was taken after evaluation of ultrasound and CT scan images. Combining pancreatic body resections and necrotic tissue excision with laparostomy and staged lavage drainage reduced global mortality rate from 49.2 to 16.4 p. cent. The criteria used for determining the indication for surgical intervention, and the technical and tactical operative procedures applied allowing this improvement, are described and discussed.     

Conditions of the thoracolumbar spine

Neurological deficits suggesting trauma to the spinal cord in the thoracolumbar area are the most common clinical presentation of neurosurgical conditions. By far, the most common cause of thoracolumbar spinal cord dysfunction is intervertebral disc disease. Disc herniation and subsequent spinal cord compression usually requires prompt medical treatment, then referral for high detail radiographs, myelogram, and surgical decompression. Other causes of thoracolumbar spinal cord dysfunction include neoplasia, discospondylitis, fibrocartilaginous embolism, and degenerative myelopathy.     

The membrane potential of Arabidopsis thaliana guard cells; depolarizations induced by apoplastic acidification

The problem of finding the number and size distribution of cell clusters that grow in an organ or tissue from observations of the number and sizes of transections of such cell clusters in a planar section is considered. This problem is closely related to the well-known corpuscle or Wicksell problem in stereology, which deals with transections of spherical objects. However, for most biological applications, it is unrealistic to assume that cell clusters have spherical shapes since they may grow in various ways. We therefore propose a method that allows for more general spatial configurations of the clusters. Under the assumption that a parametric growth model is available for the number and sizes of the cell clusters, expressions are obtained for the probability distributions of the number and sizes of transections of the clusters in a section plane for each point in time. These expressions contain coefficients that are independent of the parametric growth model and time but depend on which model is chosen for the configuration of the cell clusters in space. These results enable us to perform estimation of the parameters of the growth model by maximum likelihood directly on the data instead of having to deal with the inverse problem of estimation of three-dimensional quantities based on two-dimensional data. For realistic choices of the configuration model, it will not be possible to obtain the exact values of the coefficients, but they can easily be approximated by means of computer simulations of the spatial configuration. Monte Carlo simulations were performed to approximate the coefficients for two particular spatial configuration models. For these two configuration models, the proposed method is applied to data on preneoplastic minifoci in rat liver under the assumption of a two-event model of carcinogenesis as the parametric growth model.     

Expression levels of B-50/GAP-43 in PC12 cells are decisive for the complexity of their neurites and growth cones

To study the role of the protein B-50/GAP-43 in NGF-induced neurite outgrowth, a number of stable PC12 subclones with either very low or considerably enhanced expression levels of the protein were selected. Cell bodies of subclones with suppressed B-50 expression (-B2, -B5, or -B12) possessed a relative small spherical shape and, on NGF-treatment for 7 d, developed processes that were virtually devoid of branches and that mostly bore short or blunt-ended growth cones. Cells of subclones with overexpression of B-50 (+B3, +B4, or +B11), on NGF treatment, acquired a flattened, spiky appearance with highly branched neurites possessing extended and complex growth cones. Confocal microscopy with immunofluorescence for B-50 and F-actin revealed that in neurites and growth cones of the B-50-deficient subclone -B2, no detectable B-50 and reduced amounts of filamentous F-actin were present, whereas in overexpressing +B3 cells, cell membranes, neurites, and complex growth cones were intensively stained for B-50 and exhibited numerous spikes, in which B-50 was strikingly colocalized with F-actin. These data suggest that, under normal conditions of neuritogenesis, the expression level of B-50 in PC12 cells is decisive for the complexity of neurites and growth cones.     

Cilia incarnata

In connexion with three case reports of cilia incarnata (examples of both cilium incarnatum externum and cilium incarnatum internum), the aetiology and the signs and symptoms of this infrequently recognized anomaly are described.