THE PRESENCE OF INTRACYTOPLASMIC CONFRONTING CISTERNAE OF THE ENDOPLASMIC RETICULUM IN OSTEOSARCOMA CELLS IN INTERPHASE

Confronting cisternae of the endoplasmic reticulum recognized in tumor cells of 7 cases of osteosarcoma were presented. They were found in the mitotic cells as well as in the cytoplasms of interphase cells. The more the mitotic cells were observed in 1 μm-thick sections, the more frequently those membranous structures were encountered in the corresponding ultrathin sections. In the interphase cells, such structures were located around Golgi apparatus or close to the nucleus. Occasionally, they were composed of a pair of closely apposed cisternae of the nuclear membrane and the rough endoplasmic reticulum. These results seem to indicate that the nuclear envelope which is disrupted and reformed during mitosis in rapidly proliferating cells takes part in the formation of the confronting cisternae of the endoplasmic reticulum.     

Hepatoblastoma in an 82-year-old man. An autopsy case report

An autopsy case of adult hepatoblastoma is presented. The patient was an 82-year-old male with chronic hepatitis of 7 years' duration. The liver tumor was detected 6 months before death. Autopsy revealed a large hepatic tumor occupying about 80% of the entire liver. Histologically, the tumor showed typical features of mixed epithelial- and mesenchymal-type hepatoblastoma. The epithelial component consisted of fetal and embryonal cell types. The mesenchymal component showed primitive spindle-shaped cells with various degrees of cellularity. Chondroid areas and a few foci of osteoid formation were also present.     

A case of atypical granular cell tumor of the neurohypophysis

A case of granular cell tumor (GCT) arising in the neurohypophysis of a 63-year-old woman is reported. The tumor consisted of ovoid, polygonal or spindle-shaped cells in a sheet-like or fascicular arrangement. Its abundant cytoplasm contained granules positive for diastase-resistant periodic acid-Schiff reaction. Ultrastructurally, the tumor cells contained numerous polymorphic lysosomes of various densities. Immunohistochemically, the tumor cells were positive for S-100 protein, glial fibrillary acidic protein and Leu7, suggesting that the tumor originated from pituicytes that were thought to be modified astrocytes in the neurohypophysis and its stalk. The granular cells showed nuclear atypia, pleomorphism and increased mitotic activity. Therefore, the present tumor was considered as a histologically atypical GCT. Interestingly, proliferating cell nuclear antigen, Ki-67 and p53 were stained in a few tumor cells of this case. These findings indicate that the present tumor had a malignant potential.     

Uneven distribution of enzymatic alterations on the liver cell surface in experimental extrahepatic cholestasis of rat.

The effect of bile duct ligation on enzyme activities in the subfractions of the rat liver plasma membrane was investigated. Two subfractions were isolated from the rat liver plasma membrane by homogenization and subsequent centrifugation in a discontinuous sucrose gradient. The light subfraction contained fragments of the bile canalicular surface and the heavy fraction contained fragments of the sinusoidal and lateral surfaces of the hepatocyte. Bile duct ligation decreased NaK ATPase and Mg-ATPase activity in the light subfraction, whereas it had no significant effect on these enzyme activities in the heavy fraction. Leucyl-β-naphthylamidase activity was reduced and alkaline phosphatase activity was increased in both subfractions. These facts suggested that ligation of the bile duct led to loss of the secretory polarity of the liver cell. The in vitro effects of some bile acids on the membranebound enzymes in the light subfraction were investigated, and a possible involvement of chenodeoxycholic acid in the alteration of enzyme activities in the bile canalicular membrane was suggested.     

Clinical significance of determination of serum RNase activities in patients with eosinophilia--II. Measurements using polyuridylic acid and polycytidylic acid as substrates

The activities of RNase (RNase-U and RNase-C) were determined in the serum and leukocytes of 277 patients with 14 cases of various kinds of eosinophilia (not less than 10(3)/microliters), 28 cases of chronic myelocytic leukemia (CML), using polyuridylic acid and polycytidylic acid as synthetic substrates according to the method of Raddi et al. Serum RNase-U activity, serum RNase-C activity and the activity ratio (U/C x 10(-3)) were 55 +/- 14 U, 1,280 +/- 235 U and 44 +/- 11 (mean +/- SD), 196 +/- 137, 1,992 +/- 1,134 U and 97 +/- 38, and 110 +/- 50 U, 1,854 +/- 625 U and 65 +/- 13 for normal subjects, eosinophilia and CML (untreated), respectively. U/C ratio in eosinophilia and CML (untreated) showed a highly significant positive correlation (p less than 0.001) with peripheral eosinophil count; the activity of serum RNase-U per cells in the supernatant of eosinophil homogenate rose significantly (p less than 0.001) compared with that of lymphocytes or granulocytes. Besides, serum and eosinophil RNase-U had a similar optimal pH. These results suggested that serum RNase-U in eosinophilia originated mostly from eosinophils and its rise was correlated strongly with the increase in eosinophils.     

Induced production of nitric oxide and sensitivity of alveolar macrophages derived from mice with different sensitivity to Coxiella burnetii

We compared in vitro sensitivities to Coxiella burnetii of alveolar macrophages, derived from mice sensitive and resistant to C. burnetii, respectively, and examined the role of nitric oxide (NO) in the C. burnetii infection. Alveolar macrophages of sensitive A/J mice showed a larger population of C. burnetii antigen-positive cells than those of resistant C57BL/6 mice. C. burnetii induced NO production in alveolar macrophages, but N-methyl-L-arginine and sodium nitroprusside (SNP), NO inhibitor and donor, respectively, did not inhibit the infection. Thus the NO induction seems to be independent of the cell defense mechanism against the C. burnetii infection.     

Detection of Mason-Pfizer monkey virus infection by syncytia formation of human cells doubly transformed by Rous sarcoma virus and simian virus 40

Summary Human cells doubly transformed by Rous sarcoma virus and SV40 (RSb cells) formed syncytia by cocultivation with Mason-Pfizer monkey virus (MPMV)-producing cells. This cell fusion was blocked by anti-MPMV serum indicating that the phenomenon is MPMV specific. The RSb cells were successfully used for MPMV infectivity assay in the same manner as KC cells.With 1 Figure     

Cross-correlation studies of movement-related cortical potentials during unilateral and bilateral muscle contractions in humans

A useful method of studying the degree of association between two signals of varying amplitude in the time domain is to use cross-correlation analysis. We applied this to the movement-related cortical potentials digitally filtered so as to eliminate the low frequency component before applying it during maximal unilateral left (UL L), unilateral right (UL R) and bilateral (BL) contractions in I I right-handed subjects. The recording electrode sites were over the right and left motor cortex areas (C3 and C4). The BL condition revealed higher cross-correlation levels of cortical activities between the two hemispheres than in UL L or UL R contraction [UL L, r = 0.68 (SEM 0.05); UL R, r = 0.73 (SEM 0.03); BL, r = 0.76 (SEM 0.02)]. The UL R revealed a positive phase difference [5 (SEM 2) ms] when the maximal cross-correlation coefficient was shown and UL L showed a negative phase difference [5 (SEM 3) ms]. However, BL revealed a smaller phase difference [2 (SEM 1) ms] than that for UL. It was concluded that during maximal BL contraction cortical cellular activities in both hemispheres was more synchronized in amplitude and time course compared with maximal UL contractions. Our data suggested that central common drive existed between the right and left motor areas during the maximal BL handgrip contractions and the amplitude of potentials of both hemispheres was modified by the interhemispheric inhibition mechanism as reported in other studies.