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The morphological alterations of hepatocytes of female zebrafish, Brachydanio rerio, and fingerling rainbow trout, Salmo gairdneri, following prolonged exposure to 0.04, 0.2 and 1 mg/L of 4-chloroaniline were investigated by means of light and electron microscopy. Changes in peroxisomes were visualized by cytochemical demonstration of catalase activity after incubation in the alkaline diaminobenzidine medium. The amount of storage products was illustrated by the silver impregnation technique. In a dose-dependent manner, the reaction of female zebrafish liver is characterized by a disturbance of hepatocytic compartmentation, progressive fenestration and fractionation of the rough endoplasmic reticulum (RER), a decrease in the number of peroxisomes and catalase activity, stratified inclusions in mitochondria, and an augmentation of lysosomes and myelinated bodies. Trout hepatocytes display nuclear inclusions, fractionation and vesiculation of the RER, and an increase in mitochondria, but a decrease of peroxisomes and catalase activity. Whereas glycogen stores are exhausted at 1 mg/L 4-chloroaniline, lipid deposits are amplified. An elevated rate of hepatocytic mitosis as well as the occurrence of glycogen-condensing cells probably derived from hepatocytes indicate the induction of proliferative processes in trout liver. Evaluation and comparison of results with earlier reports suggest that despite the unspecificity of some alterations the combination of pathological symptoms yields a syndrome specific of the species and the substance studied. As a consequence, histological and cytological investigations are recommended as a routine supplement in an integrated test schedule for the assessment of sublethal effects of pollutants in the aquatic environment.

We report immunohistological findings in liver, spleen, brain, and skeletal muscle of a 23-year-old woman with hepatitis nonA/nonB caused by contaminated anti-D-globulin. She died in a liver coma. At autopsy, a chronic liver dystrophy with cirrhosis was diagnosed. The necrotic areas of the liver showed a collapse of the reticulin framework, newly formed collagen fibres, and diffuse inflammation with immunohistological evidence of IgG, CIq, C9, and fibrinogen. C4 and C9 could be localised in bile thrombi and in the cytoplasm of pseudotubular transformed hepatocytes. In addition, C9 was found in blood vessel walls. A local distribution of HBsAg was found in the cytoplasm and/or the periphery of liver cells. HBcAg could not be detected in any of 5 different regions of the liver. A serum with antibodies to acute phase antigen of nonA/nonB hepatitis stained the cytoplasm and nuclei of (mostly intact) liver cells focally and their cell membranes diffusely. Patchy deposits of IgA and IgM were demonstrated in liver, brain und spleen. Circulating antibodies to cell nuclei and smooth muscle reacted with the patient's own liver and brain but not with spleen and skeletal muscle.--It is suggested that the manifold immunohistological findings in this patient are an expression of the vain attempt of the organism to clear away antigenic material, probably induced by different hepatitis viruses.

A simple and efficient method is presented for the extraction of DNA from hair shafts. DNA preparations obtained by this approach can be made amenable to restriction enzyme digestion, thereby allowing further molecular biological analysis.

The gill epithelium of the airdwelling fish Periophthalmus vulgaris has been studied with the electron microscope. The following celltypes can be distinguished: flat covering epithelial cells, chloride cells, mucous cells, basal cells, various leucocytes as well as a specific granule containing cell which is possibly an epithelial cell. The covering epithelial cells exhibit a relatively smooth apical surface and contain in their apical half densely packed microfilaments, pinocytotic vesicles are rare. These characteristics are not to be found in water dwelling fish and possibly represent adaptations to the air containing surroundings. In the chloride cells are numerous, especially in the basal halves of the secondary lamellae. The distal parts of the secondary lamellae the barrier for the respiratory gases measures about 0,9 micrometer. The basal cells are ribosome rich replacement cells. Two types of mucous cells occur. Individual intraepithelial nerve fibres have been observed.

The morphological alterations of hepatocytes of golden ide, Leuciscus idus melanotus, following adaptation to low and high temperatures (14 and 28 degrees C) were investigated by means of light and electron microscopy. The temperature-dependent behaviour of peroxisomes was visualized cytochemically with the alkaline diaminobenzidine medium; the morphological studies were supplemented by the biochemical determination of catalase activity. Cold adaptation of ide hepatocytes is manifested by proliferation and stacking of endoplasmic reticulum, an enhanced secretory activity of Golgi fields and a higher number of peroxisomes as compared with the warm-adapted animals. The latter organelles are characterized by a marked heterogeneity in size, shape and catalase activity, and by a more intimate association with mitochondria and endoplasmic reticulum. The occurrence of small peroxisomal profiles is restricted to lower temperature. Catalase activity can be shown both cytochemically and biochemically to increase during cold adaptation. Whereas the number of mitochondria seems to be unaffected by thermal adaptation, stacking of mitochondria as well as the formation of intramitochondrial membrane piles indicate cold-adaptive processes. A feature typical of warm-adaptation is the formation of membrane-glycogen complexes, which may represent the morphological expression of enhanced carbohydrate metabolism documented in a decreased storage of glycogen at 28 degrees C. At 28 degrees C lipid is the predominant storage product. These findings indicate that fish liver is well-suited to serve as a model for the analysis of the interaction of environmental temperature conditions and hepatic morphology.

Epithelial and cuticular linings of the stomach investigated in three species representing different genera of the Mysidacea are elaborated into a set of structural specializations dividing the stomach longitudinally into one dorsal and two ventral channels. The dorsal, or food, channel contains ingested food and retains coarse particles, which eventually are transported into the midgut through a funnel. The ventral, or filtration, channels, which are separated by an anterior and a posterior median ridge (anteromedianum, inferomedianum), contain fine particles and soluble materials extracted from the dorsal channel through two filter systems: primary filters, which lie anteriorly on either side of the anteromedianum, and posterior secondary filters, which are located on the inferomedianum. The final filtrate is transported into the ventral caeca or midgut glands. The ultrastructure of the cuticle lining the lumen of the stomach shows several specializations, the most prominent of which are stout spines and delicate filter devices. The epithelium is multilayered in circumscribed areas (the lateralia). The basement lamina is extremely developed in the inferomedianum. Detailed knowledge of the microscopic anatomy and the ultrastructure of the stomach allows identification of several homologous gastric structures among different peracaridean groups and in Decapoda., (Copyright © 1989 Wiley-Liss, Inc.)

Three types of sensilla occurring on the lips and on the antennae of Peripatopsis moseleyi have been investigated by scanning and transmission electron microscopy. On the lips sensory spines can be found which contain numerous cilia originating from bipolar receptor cells. They reach the tip of the spine where the cuticle is modified. The perikarya of the sensory cells, a large supporting cell with a complicated surface and a second type of receptor, form a bud-like structure and are surrounded by a layer of collagen fibrils. The second receptor cell bears apical stereocilia as well as a kinocilium which are directed towards the centre of the animal -- thus the cell appears to be turned upside down. The sensilla of the antennae are 1) sensory bristles containing two or three kinds of receptor cells, one of which bears an apical cilium and one kind of supportive cell and 2) sensory bulbs located within furrows consisting of receptor cells with branched cilia and two kinds of supportive cells which are covered by a modified thin cuticle. According to the electron microscopical findings the sensory spines on the lips are presumably chemoreceptors. The sensory bristles on the antennae can be regarded as mechanoreceptors and the sensory bulbs as chemoreceptors.

Red and white pulp were distinguished in the spleen of the caecilian species Ichthyophis paucisulcus and Afrocaecilia taitana. The red pulp was composed of endothelium-lined sinusoids and reticular connective tissue. Between the processes of the reticulum cells, accompanied by fine collagen fibrils, the following cell types were found: lymphocytes, macrophages (frequency containing fragments of erythrocytes), neutrophils, eosinophils, mast cells and/or basophils (metachromatic granules), thrombocytes, plasma cells, pigment cells as well as cells which presumably represent blast cells. Morphological evidence suggested the formation of thrombocytes in the red pulp. Besides sinusoids, ellipsoids and peculiar arteriolar vessels with a high endothelium and a loose layer of muscle cells were observed. Veins were concentrated in the splenic periphery. White pulp consisted of arterioles which were surrounded by a lymphocyte sheath. Follicles were not identified with certainty. Occasionally mitotic figures were associated with lymphocytes. On the basis of our findings, we suggest the following functions of the caecilian spleen: destruction of aged erythrocytes, formation of thrombo- and lymphocytes as well as of plasma cells and, to a marked lesser degree, of other blood cells.

Liver tissue of nine teleost species has been investigated electron microscopically after periods of fasting. Ultrastructural changes tn the hepatocytes are described mainly from Haplochromis burtoni. 70 days of food deprivation have the following effects: the intercellular spaces are widened; the size of the hepatocytes is reduced; lysosomes are enlarged and reach the diameter of the nucleus and have increased in number; the amount glycogen is reduced; the endoplasmatic reticulum bears less ribosomes. All alterations are reversible. The comparison of different species mainly shows differences conceming to the amount of lipid, which may be reduced or enlarged.

In a random sample of so-called healthy blood donors under and over 60 years of age (n=196 of 10,593 donations by about 4254 donors) the frequency of antibodies (antibodies against smooth muscles, mitochondria, microsomes, brush border of proximal rat renal tubuli, connective tissue, and parietal cells) detectable by immuno-fluorescence was determined and compared with the incidence thereof in various groups of diseases. In general, two frequency peaks (up to 30 and over 50 years of age) were observed; however, statistical evidence was obtained for the second peak only (with p less than 0.001). In "healthy" blood donors past 60 there was observed a significantly higher frequency of occurrence of antibodies against parietal cells (p less than 0.001) and against connective tissue (p less than 0.01). An attempt has been made to classify antibodies into four groups depending upon age disease, with due consideration being given to the different clinical valency of antibodies. Different frequencies of occurrence of numerous antibodies are believed to be due not only to immune system aging, but especially to the not-yet elucidated disturbance of regulation of autotolerance by alteration of immune cells, which is subject to endogenous (e.g., genetic) and exogenous (e.g. viral) factors that are dependent on age rather than aging.

The ultrastructure of hepatic peroxisomes was investigated in Ichthyophis glutinosus (Amphibia: Gymnophiona), employing perfusion fixation and the diaminobenzidine (DAB) technique for the visualization of catalase. The majority of peroxisomes is circular or rod-shaped, although elongated particles occasionally occur. They contain a finely granular matrix, lightly stained after the DAB procedure. Their mean diameter is approximately 0.25 micron. Serial sections reveal that the circular and rod-shaped peroxisomal profiles are cross and oblique sections of highly tortuous, tubular organelles exceeding 2 micron in length. In addition to tubular profiles, elongated, rectangular particles, as well as straight dumbbell-shaped organelles with distinct marginal plates are observed. They range from 900 to 1650 nm in length (mean = 1200 nm). In the flattened, thin central portion of the dumbbell-shaped particle, the peroxisomal membranes form a cisterna enclosing one or two uniformly thick marginal plates, which display a definite substructure with a periodicity of 10 nm. These findings indicate that peroxisomes in the liver of Ichthyophis exhibit a complex organization. It is suggested that the organelles undergo a specific differentiation process, morphologically characterized by the formation of enlarged segments of unusual shape.