Up-regulation of reactive astrogliosis in the rat glioma 9L cell line by combined mechanical and chemical injuries.

The 9L rat glioma cells grown in culture, when subjected to a mechanical injury (scratch wound) and/or a chemical injury (CdCl2) manifest changes which are characteristic of an astrocyte reaction (astrogliosis) in the central nervous system. Such changes include cell hypertrophy and an increase in immunostaining for the astrocytic marker proteins, glial fibrillary acidic protein and J1-31 antigen. Mitochondria also increase in size and number, and the endoplasmic reticulum expands in area. These mechanical and chemical injuries are coordinated, and act synergistically to induce a considerably more intense astroglial reaction by 9L cells than can be elicited with either injurious agent alone, and this occurs without any interactions with microglia, neurons or oligodendroglia. The phenomenon suggests that more than one transcriptional mechanism is involved in the activation of astrocytes, and that mechanical and CdCl2-induced injuries, respectively, probably affect different receptors and second- and third-messenger pathways. There are a number of questions concerning the molecular biology of reactive astrocytes which can be addressed through the use of the 9L rat glioma cell model. This model offers certain advantages over primary cultures of astrocytes, namely a low basal level of reactivity (because the cells are not subjected to mechanical injury prior to experimentation), an absence of contaminating microglial cells, greater ease of reproducibility of results, lower costs and avoidance of the use of animals.

The impact of surgical technique on the development of graft versus host disease in a rat small intestinal transplant model.

The small intestine and its mesentery contain a large amount of lymphoid tissue that can mediate graft-versus-host disease (GVHD) in small intestinal transplant recipients. To assess the impact of surgical technique and the retention of the recipient's small intestine on GVHD intensity, 12 adult Lewis rats received heterotopic small bowel transplants and 12 received orthotopic small bowel transplants from Brown Norway donors. Twelve Lewis to Lewis heterotopic small-bowel-transplanted animals served as the control group. All recipients were given cyclosporine (10 mg/kg/alternate days) subcutaneously. The parameters followed were: weight gain and feed intake; clinical signs of GVHD; relative spleen weight; popliteal lymph node enlargement assay; and histological evaluation of spleen, liver, skin, native intestine, and transplanted intestine. According to the clinical scoring system, heterotopically transplanted animals were found to have a more severe GVHD than the orthotopic group. There were statistically significant differences between the relative spleen weights of the heterotopic transplant group and the control group (P = 0.001, 0.004, and 0.007 on days 7, 14, and 21, respectively) and between the heterotopic and orthotopic groups at 7 days (P = 0.037). Lymph node enlargement assays were statistically different between heterotopic and orthotopic groups (P = 0.019, 0.020, and 0.007 on days 7, 14, and 21, respectively). Histological evaluation of skin biopsy specimens also demonstrated that GVHD was indeed more severe in the heterotopic transplanted group when compared with orthotopically transplanted animals. These findings confirm that retention of the native small intestine in the heterotopic intestinal transplant model significantly increases the severity of GVHD following transplantation.

Rat glioma cell line as a model for astrogliosis.

In this investigation 9L rat glioma cells were grown on coverslips in culture, and when subjected to mechanical trauma, they were capable of mounting an astroglial response, without interaction with neurons, as evidenced by cell hypertrophy and increased immunostaining for glial fibrillary acidic protein and J1-31 antigen. It is of particular interest that this neoplastically transformed cell line is capable of mounting an astroglial response when subjected to mechanical trauma in vitro. The advantages of this model over in vivo models of central nervous system injury include the ease of reproducibility of results, and the ability to investigate molecular mechanisms under controlled conditions.

Diversity among reactive astrocytes: proximal reactive astrocytes in lacerated spinal cord preferentially react with monoclonal antibody J1-31.

An Astrocyte-specific antigen recognized by monoclonal antibody J1-31 is a more intense marker for proximal reactive astrocytes in lacerated rat spinal cord than is glial fibrillary acidic protein (GFAP). Thus, MAb J1-31 recognizes reactive astrocytes in the immediate vicinity of the lesion, whereas reactive astrocytes that are located at a distance from the lesion are not detected by immunofluorescent staining. These findings are relevant to the biochemical heterogeneity manifested respectively by reactive astrocytes located proximal and distal to a laceration-type injury of the spinal cord, and those that develop following axotomy with retrograde degeneration. Reactive astrocytes in the axotomy model are not stained with MAb J1-31, but are positive for GFAP.

Ultrastructural events following acute muscle trauma.

The purpose of this study was to determine the ultrastructural events occurring in skeletal muscle following acute blunt trauma. Male rats weighing 250 g were subjected to a single impact trauma to the medial gastrocnemius muscle while under general anesthesia. Hemorrhage, inflammation, non-necrotic degeneration, and later regeneration were observed. In the short term following impact (6-24 h), the damaged segments showed gross tearing and degeneration. A large number of mononuclear cells were seen in the intercellular connective tissue and within the damaged muscle cells. By 24-48 h, there was an increase in the number of sarcolemmal nuclei, some of which were likely of satellite cell origin. By day 3, regenerating muscle cells displayed central nuclei and reorganizing sarcomeres. By day 6, further progression of regeneration was seen. Moreover, focal interstitial collagen formation suggested minimal to mild scar formation. On days 14, 21, and 30 after trauma, the muscle appeared to have healed and no abnormalities could be found at the site of injury. In parallel with the ultrastructural events noted, the injured muscles underwent a marked catabolic response and showed a reproducible fall (-27%, P less than 0.001) in total protein content within 48 h. Muscle protein accumulation commenced after day 3; however, complete repletion of the loss did not occur until day 21 post-injury.

Reactive astrocytes--a review.

This review provides an historical and current perspective on astrocytes in the CNS, detailing their morphological and biochemical diversity, origins and transformation to reactive astrocytes in experimental lesions and clinical disease states which result in gliosis. Recent studies on reactive astrocytes have been facilitated by the availability of immunocytochemical probes for GFAP and other distinctive cellular components. The effects in vitro of 'growth factors' on astrocytic transformation are briefly considered. An understanding of astrocytic transformation has implications for neural transplantation.

Multicentric gastric carcinoids complicating pernicious anemia. Origin from the metaplastic endocrine cell population.

We report three cases of multicentric carcinoid tumors of the stomach in patients with long-standing pernicious anemia and severe atrophic gastritis (type A). The tumor nodules arose in nonantral gastric mucosa showing marked intestinal metaplasia. Diffuse endocrine cell hyperplasia was present in both fundus and antrum. Antral G-cell hyperplasia was observed. A widely accepted pathogenesis of this syndrome suggests that the proliferating cell type is the argyrophilic, enterochromaffinlike cell native to the gastric body and fundus. Our findings conflict with this view, in that focal argentaffin staining was also present within tumor cells, as well as immunoreactivity for serotonin and substance P (more characteristic of small-intestinal enterochromaffin or Kulchitsky's cells and small-intestinal carcinoids). Findings in these cases at least suggest an alternative possibility: the tumors may derive from small-intestinal-type metaplastic endocrine cells within the atrophic mucosa, rather than the hypertrophic native endocrine cell population.

Aspiration biopsy cytology of mammary myoepithelioma.

A case of ultrastructurally confirmed myoepithelioma of the breast studied by fine-needle aspiration biopsy is reported. Aspirated tumor cells were spindle-shaped with well-defined cytoplasm and oval nuclei showing no remarkable nuclear pleomorphism. They were seen mainly in irregular bundles with strong cellular cohesiveness. Their cytoplasm contained S-100 protein demonstrated by the peroxidase antiperoxidase staining technique.

Aspiration biopsy cytology of adenocarcinoid tumor of the bronchial tree.

Aspirated material from two cases of histologically and ultrastructurally confirmed adenocarcinoid tumor of the lung was evaluated. In one case, columnar and cuboidal cells with ill-defined cytoplasm and round or oval nuclei were seen in large sheets and syncytiumlike clusters with focal glandular arrangement. In the other case, spindle-shaped and columnar cells with ovoid nuclei and ill-defined cytoplasm were seen singly and in loose clusters. Fragments of tumor epithelium with nuclei arranged in pseudo-stratified pattern were noted. Staining of tumor cells by the Grimelius technique demonstrated numerous intracytoplasmic brown-black granules. The cytologic differential diagnosis between adenocarcinoid tumor and other primary and metastatic adenocarcinomas of the lung is briefly discussed.

Technetium pyrophosphate labelling following catheter shock: potential for a new intraoperative mapping technique.

Technetium pyrophosphate uptake at the site of catheter shock was studied in four patients and seven experimental dogs. Technetium pyrophosphate scintigraphy was performed following five catheter ablation attempts in humans at different cardiac sites, and following 24 J catheter shocks delivered in the right and left ventricles of seven dogs. In the patients, gamma camera imaging with tomographic reconstruction showed intense focal uptake at the sites of shock. The scans were positive from 1.5 to 5.5 h following ablation and stayed positive for up to five days. In the animals, the low energy shocks produced circumscribed areas of coagulation and contraction band necrosis. The binding of technetium pyrophosphate at these sites was confirmed by in vivo gamma camera imaging, epicardial counting with a 1.2 cm scintillation probe and ex vivo imaging. Ratios of focal binding to normal myocardial uptake of technetium pyrophosphate were calculated from the digital gamma camera images. In all cases, technetium pyrophosphate was bound to myocardial sites where transcatheter energies were delivered in both humans and dogs. Intraoperative localization of the origin of tachycardia in man may be facilitated by combining preoperative endocardial catheter mapping, catheter shock, radionuclide labelling of the site of shock and a search for the focus of radionuclide concentration during subsequent surgery.

Phagocytosis of platelets by Kupffer cells in immune thrombocytopenia.

Phagocytosis of platelets by Kupffer cells has long been suspected in immune thrombocytopenia. We describe a patient with Hodgkin's disease who also had immune thrombocytopenia. Surface localization studies with chromium 51-labeled platelets showed predominant hepatic localization of radioactivity, and the thrombocytopenia did not respond to splenectomy. Subsequent chemotherapy with immunosuppressive drugs led to remission of the thrombocytopenia. In this patient, phagocytosis of platelets by Kupffer cells was demonstrated by electron microscopy, and the degree of platelet phagocytosis in the liver was greater than in the spleen. This provides direct evidence that, at least in some cases of immune thrombocytopenia, platelets are phagocytosed by Kupffer cells.

The osteoclast-type giant cell tumor of the pancreas.

We present a case report of osteoclast-type giant cell tumor of the pancreas and review the literature concerning this rare neoplasm, the histogenesis of which is uncertain. Electron microscopic features have suggested stromal, histiocytic, and epithelial origins to different investigators. Analysis of the present case supports and epithelial origin, with positive immunocytochemical staining for carcinoembryonic antigen and for low molecular weight keratin in the mononuclear and in some osteoclastlike giant cells. These tumor cells did not stain for mesenchymal markers (lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, S100 protein). Zymogen granules, desmosomes, and zonulae occludentes were identified ultrastructurally and further support an epithelial derivation.

Exfoliative cytology of clear-cell sarcoma metastases in pleural fluid.

Two cases of clear-cell sarcoma arising from the leg with widespread metastasis were reported. Exfoliated tumor cells in pleural effusions were round, oval, and slightly pleomorphic. They were seen singly or in clusters of variable size with marked cellular cohesiveness and molding. Their cytoplasm was well-defined, clear, or finely granular, and contained S-100 protein and periodic acid-Schiff positive material that was digestible by diastase. Tumor-cell nuclei were round and hyperchromatic with irregular chromatin clumping, and showed conspicuous nucleoli.

Cardiac amyloidosis: combined use of two-dimensional echocardiography and electrocardiography in noninvasive screening before biopsy.

Cardiac amyloidosis (CA) presenting with intractable congestive heart failure, electrocardiographic (ECG) normal or low voltage, and conduction or rhythm disturbances, is rapidly fatal. During life, CA often mimics other cardiomyopathies so that definitive diagnosis depends on demonstration of amyloid on myocardial biopsy. On two-dimensional echocardiography (2-D echo), nonspecific features, such as increased ventricular wall thicknesses, predominant diastolic dysfunction, and diffuse myocardial "sparkling," are consistently found in CA. The combined presence of these 2-D echo features and normal or low voltage on ECG is highly suggestive of CA, allows differentiation from other cardiomyopathies, and might be useful in noninvasive screening before myocardial biopsy.

Malignant fibrous histiocytoma of prostate gland.

The English language medical literature does not contain any definitive reports of malignant fibrous histiocytoma (MFH) arising in the prostate gland. A case of prostatic MFH is described, characterized by rapid local tumor progression and pulmonary metastases. The histologic diagnosis was supported by immunohistochemical and electron microscopic studies.

"Shaker" calf syndrome: a newly recognized inherited neurodegenerative disorder of horned Hereford calves.

The clinical and pathological features of a newly recognized, inherited neurodegenerative disorder in horned Hereford calves are described. The disorder is expressed in newborns by tremulous shaking of the head, body and tail, difficulty in rising, a wobbly spastic gait, and aphonia. Transient improvement is followed by deterioration and progressive spastic paraplegia. Generalized tremors can be induced easily by a variety of stimuli, and spinal reflexes may be exaggerated or depressed. The major pathological finding is an excessive accumulation of neurofilaments within neurons of the central, peripheral, and autonomic nervous systems. The involvement of multiple systems of neurons and the similarity with some forms of human motor neuron disease and spinocerebellar degeneration suggest that this unique bovine disease may serve as a suitable animal model for these human neurodegenerative disorders.

Papillary cystic tumor of the pancreas.

We studied three cases of papillary cystic tumor of the pancreas and reviewed the literature concerning this uncommon neoplasm. This tumor almost always behaves in a benign fashion and occurs predominantly in young women. The histogenesis remains uncertain, but results of electron microscopic and immunocytochemical studies are consistent with an origin from a primitive cell capable of differentiating along both acinar and endocrine lines.

Effect of doxorubicin on [omega-I-131]heptadecanoic acid myocardial scintigraphy and echocardiography in dogs.

The effects of serial treatment with doxorubicin on dynamic myocardial scintigraphy with [omega-I-131]heptadecanoic acid (I-131 HA), and on global left-ventricular function determined echocardiographically, were studied in a group of nine mongrel dogs. Total extractable myocardial lipid was compared postmortem between a group of control dogs and doxorubicin-treated dogs. A significant and then progressive fall in global LV function was observed at a cumulative doxorubicin dose of 4 mg/kg. A significant increase in the myocardial t1/2 of the I-131 HA was observed only at a higher cumulative dose, 10 mg/kg. No significant alteration in total extractable myocardial lipids was observed between control dogs and those treated with doxorubicin. Our findings suggest that the changes leading to an alteration of myocardial dynamic imaging with I-131 HA are not the initiating factor in doxorubicin cardiotoxicity.