Human Adenovirus-Induced Medulloepitheliomatous Neoplasms in Sprague-Dawley Rats

A direct causal relationship between a human virus and malignant transformations in target cells (sensory neuronal precursors) was suggested by the development of a medulloepitheliomatous neoplasm in the central nervous system. Twenty-six newborn Sprague-Dawley rats were given a single intracerebral inoculation of 0.05 ml of adenovirus fluid, 10^3.5 to 10^4.5 TCID₅₀ HeLa cells/0.1 ml, in the left frontal lobe. Within 37 to 151 days after the virus inoculation, 23 (88.7%) rats autochthonously developed an adenovirus-typical neoplasm in the central nervous system. Nine animals developed a multicentric neoplasm closely related to the ventricular system. Nine others developed solid variously sized neoplasms along the ventricular lumen. Some neoplasms showed multiple foci connected with the stratum subependymale ventriculi olfactorii and the velum medullare of the fourth ventricle. Six spinal cord tumors, located chiefly in the dorsal sensory column, developed within 37 to 61 days after intracerebral inoculation. The remarkably uniform histopathologic appearance of all 23 cases was attributed to a medulloepitheliomatous neoplasm derived from the ependymal anlage. Electron microscopy clearly revealed a solitary cilium within the apical region of many tumor cells. It consisted of a typical ring of nine doublets with no axial pair (a 9+0 pattern), the typical structure of cilia of sensory neuronal origin. The appearance of exuberant neuron-like tumor cells with argyrophile cytoplasmic expansions, neurosyncytial mosaic alignment and myelin-like configurations also suggested a neuronal origin. A paucity of mesenchymal stroma in the neoplastic tissue was noted. No control animals developed tumors.     

Zoster meningitis and radiculomeningitis after tick bite. Cytological findings in cerebrospinal fluid.

Cytological changes in 9 samples of cerebrospinal fluid (CSF) from 5 patients with zoster meningitis and 12 samples from 5 patients with radiculomeningitis after tick bite were examined. 5 days after the onset of the skin eruption, the CSF cells in zoster meningitis consisted of many mononuclear blast forms--large lymphocytes and 'immature' plasma cells. 11-15 days after the onset of the skin rash, they were replaced by small lymphocytes, some 'mature' plasma cells and monohistiocytes. In radiculomeningitis after tick bite, however, the CSF cells examined 10-21 days after the onset of radicular pain consisted of many large lymphocytes, immature plasma cells and a few neutrophils. From these findings, it might be suggested that the acute meningeal reaction of zoster meningitis subsides within about 1 week after the onset of the skin rash, but that of radiculomeningitis after tick bite continues at least for 2-3 weeks after the onset of radicular pain.     

Nuclear and Cytoplasmic Inclusion Bodies in Pinealocytes of the Cotton Rat, Sigmodon hispidus: An Electron Microscopic Study

Electron microscopic observations on pinealocytes of cotton rats (Sigmodon bispidus) killed in October revealed the presence of cytoplasmic inclusion bodies (CIBs) and two kinds of nuclear inclusions--coiled bodies and granular inclusion bodies. These inclusions were usually not bounded by a membrane. CIBs showed round or irregular profiles and consisted of granular and filamentous materials of moderate electron opacity intermingled with electron-lucent areas. Nuclear granular inclusions appeared as homogeneous or heterogeneous granules of variable electron opacity, which usually exhibited round profiles of variable diameters and consisted of granular and filamentous elements. Electron-opaque granules were observed in perinuclear spaces, dilated cisternae of rough endoplasmic reticulum, as well as in the central portion of CIBs. In CIBs containing granules, the peripheral region was composed of the moderately electron-opaque substance seen in usual CIBs, while the central core was occupied by a granular and filamentous substance and an intervening electron-lucent matrix. Since an electron-opaque granular substance in nuclei, perinuclear spaces, cisternae of rough endoplasmic reticulum, and the central portion of CIBs may occur concomitantly, the granules seen in these sites may be related. Coiled bodies were round in profile and were composed of electron-opaque strands consisting of granular and filamentous elements and intervening material of low electron opacity. This structure, frequently located in close proximity to the nuclear granular inclusions, may play a role in the formation of the intranuclear granules in cotton rat pinealocytes.     

Labelled gelfoam in transcatheter arterial embolization of renal cell carcinoma

Six patients with renal cell carcinoma underwent transcatheter arterial embolization with Gelfoam labelled by metallic clips. The embolization procedure was more easily monitored by fluoroscopy, and the complication of peripheral embolization was prevented. Tumor regression can be evaluated by changes in the distribution of the metallic clips on plain films.     

Enzyme immunoassay of human protein C by using monoclonal antibodies

An enzyme-linked immunosorbent assay (ELISA) for measuring human protein C by using two monoclonal antibodies directed toward the heavy chain of protein C is reported. This assay enabled the determination of protein C in concentrations of 10 to 400 ng/ml in less than 3 hours with a single antigen-antibody reaction. Within-run and between-run coefficients of variation were less than 8%. The mean concentrations of protein C in plasma of 42 normal subjects, 24 patients with liver disease, 27 with DIC, 48 with warfarin therapy and 15 with congenital protein C deficiency, were 4.2, 3.0, 2.3, 2.1 and 1.9 μg/ml, respectively. The results obtained with the present ELISA correlated well with those of radioimmunoassay (r=0.935, N=81) as well as those of Laurell's Rocket method (r=0.910, N=81) by using rabbit anti-human protein C serum. The present method was sensitive and specific for measurement of protein C and also PIVKA-protein C in plasma.