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The effect of glucosamine on phenotypic mixing between vesicular stomatitis virus (VSV) and avian sarcoma virus (ASV) was studied. Phenotypic mixing decreased with increase in glucosamine concentration, and, in the presence of 20 mM glucosamine, was no longer detectable. In the presence of 20 mM glucosamine, cells still produced 10(2)--10(3) focus forming units (FFU) of ASV and 10(6) plaque forming units (PFU) of VSV per milliliter. These results suggest that cells producing a relatively large amount of ASV (more than 10(3) FFU/ml) are essential for phenotypic mixing of VSV with ASV.

Fifty patients with chronic myelocytic leukemia (CML) grouped into four stages on the basis of clinical and hematological results were analyzed with chromosomal banding techniques. Of the 50 patients, 48 hand the "standard" type of Ph1 translocation, t(9 ; 22) (q34 ; q11) and the remaining 2 had Ph1-negative diploid karyotype. The frequency of numerical chromosomal changes and/or structural chromosomal changes other than the Ph1 translocation varied with the stages; the frequency was 1 of 28 cases (3.6%) for patients in stage I (chronic phase), 5 of 11 (45.5%) in stage II (early stage of blastic phase), 11 of 13 (84.6%) in stage III (blastic phase) and 2 of 7 (28.6%) in stage IV (remission phase). Numerical changes in hyperdiploid leukemic cells correlated well with the appearance of extra #8 and extra Ph1 In 5 cases with hypodiploid leukemic cells, one of the #7 pair was absent in 4 cases and Y in 1 case. As structural changes, partial excess of chromosome 1, isochromosome 17q, isochromosome 1q, tdic (20p+ ; 21q-), del (7) (q11), t(2p+ ; 11p-), #12q+ and Xp+ were observed. Chromosomal analysis alone is not the best marker to diagnose the onset of blastic phase; however, it is a useful parameter when considered in combination with clinical and hematological results.

A permeable cell system has been developed by treatment with digitonin for studying in vitro DNA replication of chromatin. DNA replication of simian virus 40 nucleoprotein complexes (SV40 chromatin) in digitonin-treated permeable cells was analyzed by electrophoresis in agarose-gel. Autoradiography of the agarose-gel revealed that [32P]dCTP was incorporated in SV40 DNA I, II and replicating intermediates. The time course of the incorporation indicated the complete replication of SV40 DNA and chromatin with a full number of nucleosomes. The digitonin-treated permeable cell system will serve as a useful system for studying in vitro DNA replication of chromatin.

The effects of coenzyme Q10 (Co Q10) on potassium ion release, membrane potential and fluidity of rabbit red blood cells were studied. Co Q10 inhibited the increased potassium ion release induced by cetylamine or lysolecithin from the cells. Co Q10 slightly decreased the membrane potential monitored by changes in fluorescence intensity of cyanine dye, 3,3'-dipropyl-2,2'-thiodicarbocyanine iodide [diS-C3-(5)], and also slightly decreased the membrane fluidity measured by using 1,6-diphenyl-1,3,5-hexatriene (DPH). These effects of Co Q10 on the membrane are considered to be due to its membrane stabilizing activity by interaction with lipid bilayers of the membrane.

The experiment was designed to observe the possible relation between myelopoietic and erythropoietic activities of circulating nucleated cells. Wistar rats were lethally irradiated with 60Co, 100 r once. Two days after irradiation the bone marrow cells had faded completely. At this stage animals were conjugated with normocythemic or polycythemic rats by aortic anastomoses. After conjugation the aplastic bone marrow of the irradiated animal rapidly regained its hemopoietic activity in cases having normocythemic and polycythemic partners. Active erythropoiesis and myelopoiesis were found 96 h after parabiosis in those having normocythemic partners. In animals having polycythemic partners, however, erythropoiesis was successfully suppressed. An increase in lymphoid cell numbers was found in place of decreased erythroid cells, but there was no change in the myeloid cell proliferation rate. No hemopoietic precursor cells or immature cells were found in circulating blood all through the experimental period before and after parabiosis. The data suggest that circulating nucleated cells have marked erythropoietic activity. Erythropoietic cells may be somehow related to lymphoid cells independent of myelopoietic activity.

A 30 year old female patient diagnosed as acute lymphoblastic leukemia (ALL) with hand mirror like configuration of lymphoblastic-lymphocytic cells is reported. Although the leukemia was resistant to conventional chemotherapeutic regimens, the patient always looked well and survived for more than 20 months. Surface marker analysis showed that the cell was non-T, non-B, and not reactive to antiserum against common ALL antigen. A cytogenetic study of all the analyzable metaphases of the direct bone marrow preparation had a normal female karyotype. The clinical and hematological course is described. The immunological significance and the influence of hand mirror cell on chemosensitivity and prognosis are discussed.

This study was conducted to examine the effect of gamma-interferon (IFN-gamma) on experimental metastasis formation by murine colon 26 adenocarcinoma in BALB/c mice. We found that the number of experimental lung metastases was increased after colon 26 cells were pretreated for 1 h with as little as 1 OIU/ml of IFN-gamma. 5-[125I] iodo-2'-deoxyuridine-radiolabeled colon 26 cells pretreated with IFN-gamma remained at higher level in the lung at 24h after intravenous injection than when the cells were not pretreated. In vivo elimination of asialo GM1-positive cells increased the number of lung metastases and, in such mice, there was no longer a difference in metastatic ability between control and IFN-gamma-treated cells. Colon 26 cells were completely resistant to lysis by isolated splenocytes. Splenocytes incubated in vitro with interleukin 2 exhibited moderate cytotoxicity against colon 26 cells, but there were no significant differences between control and IFN-gamma-treated cells. Colon 26 cells pretreated with IFN-gamma demonstrated resistance to tumor necrosis factor alpha-mediated growth inhibition. The enhancement of metastases by IFN-gamma was dependent on de novo protein synthesis since the enhancement was abolished by cycloheximide. Taken together, the data suggest that the metastatic ability of colon 26 cells pretreated with IFN-gamma is significantly higher due to the resistance to asialo GM1-positive cells accompanied with de novo protein synthesis.

Circulating hepatitis C virus (HCV) particles can be fractionated by means of differential flotation centrifugation. It is reported that in the bottom fraction HCV is in the form immune complexes, whereas in the top, it is free of antibodies. We evaluated the significance of circulating complex and free HCV in chronic hepatitis C, and assessed the relationship in terms of the response to interferon (IFN) therapy. We examined sera before, just after, and 1 year after administering IFN to 18 patients with chronic hepatitis C, 10 of whom responded (group CR), and 8 did not (group NR). The amounts of virus were similar between both groups before therapy. After differential flotation centrifugation with 1.063 g/ml of NaCl, the top and bottom fractions were assayed for HCV RNA. Before therapy, HCV RNA was detected in the top fraction in 1 of 10 in group CR, and in 6 of 8 in group NR (P < 0.05, chi-square test). HCV RNA was positive in the bottom fraction of all samples. In a follow-up study of group NR, HCV RNA was detected in the top fraction in 3 of 8 just after IFN therapy, and in 7 of 8 after 1 year. This study suggests that the presence of HCV in the top fraction can predict a poor response to IFN therapy.

We purified an apurinic/apyrimidinic (AP) endonuclease from mouse ascites sarcoma (SR-C3H/He) cells. The enzyme showed nicking activity on acid-depurinated DNA but not on untreated, intact DNA. It also showed priming activity for DNA polymerase on both acid-depurinated and bleomycin-damaged DNA. The priming activity on bleomycin-damaged DNA was two times higher than that on an acid-depurinated DNA. The enzymatic properties indicate that the enzyme is a class II AP endonuclease having DNA 3' repair diesterase activity. The purified enzyme has a molecular weight of 39,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimal pH for AP endonuclease activity was 8.0 in 50 mM Tris-HCl buffer. The AP endonuclease activity depended on divalent cation such as Mg2+ and Co2+ ions, and was inhibited by 2 mM EDTA with no addition of the divalent cation. An appropriate concentration of sodium or potassium salt stimulated the activity. Partial digestion of the AP endonuclease with Staphylococcus aureus V8 protease produced 4 major peptide fragments which may be used for protein sequencing.

<P>We purified an apurinic/apyrimidinic (AP) endonuclease from mouse ascites sarcoma (SR-C3H/He) cells. The enzyme showed nicking activity on acid-depurinated DNA but not on untreated, intact DNA. It also showed priming activity for DNA polymerase on both acid-depurinated and bleomycin-damaged DNA. The priming activity on bleomycin-damaged DNA was two times higher than that on an acid-depurinated DNA. The enzymatic properties indicate that the enzyme is a class II AP endonuclease having DNA 3' repair diesterase activity. The purified enzyme has a molecular weight of 39,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimal pH for AP endonuclease activity was 8.0 in 50 mM Tris-HCl buffer. The AP endonuclease activity depended on divalent cation such as Mg2+ and Co2+ ions, and was inhibited by 2 mM EDTA with no addition of the divalent cation. An appropriate concentration of sodium or potassium salt stimulated the activity. Partial digestion of the AP endonuclease with Staphylococcus aureus V8 protease produced 4 major peptide fragments which may be used for protein sequencing.</P>

The sensitivity of five kinds of cytotoxicity assays using ethanol on human hepatoblastoma cells (HUH-6 line), which were cultured as monolayers or spheroids, was compared. Ethanol was chosen as a test because it acts on cell membranes directly without being metabolized and exerts its cytotoxicity. The assay methods used were as follows: 3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), colony formation, cell growth and DNA assays. The sensitivity of the assays was: LDH < DNA < cell growth < MTT < colony formation. LDH assay had the advantage that the same culture could be used for multiple assays, but when a small number of cells were assayed, no significant increase in the release of LDH was detected in the assay cultures compared with the control cultures. Although the DNA and cell growth assays were more sensitive than the LDH assay, the extent of cell damage may be underestimated because the damaged cells and DNA present in the cultures are included in the assay samples. On the other hand, both MTT and colony formation assays showed a high sensitivity. The MTT assay was done within 24 h after ethanol was added to the cultures and was applicable to both monolayer and spheroid cultures, while the colony formation assay required 1-2 weeks and it was applicable only to monolayer cultures. Taken together, the MTT assay was the most suitable method to evaluate the cytotoxic effects of ethanol on HUH-6 cells cultured as either monolayers or spheroids.

Some patients with rheumatoid arthritis (RA) as well as those with other collagen diseases are positive for antinuclear antibody (ANA). We investigated the frequency of positivity for ANA in 104 patients with RA and evaluated the clinical features and laboratory data in the ANA-positive and -negative groups. The presence of ANA in sera was studied by indirect immunofluorescence using HEp-2 cells as the antigen substrate. Sera with a positive fluorescence at a dilution of 1:20 were considered to be positive for ANA. Of the 104 patients, 39 (37.5%) were positive for ANA. The staining pattern in the positive cases varied, but most were speckled (64.1%) and homogeneous (48.7%). A small number showed a nucleolar (20.5%) or a centromere (10.3%) pattern. None showed a shaggy pattern. The ANA titer was lower in RA patients compared with those with other collagen-related diseases such as systemic lupus erythematosus or progressive systematic sclerosis. None of the patients positive for ANA with either a nucleolar or centromere staining pattern had progressive systemic sclerosis or the CREST syndrome. One patient each had Raynaud's phenomenon and pulmonary fibrosis. There was no correlation between ANA positivity and indicators of joint inflammation. The prevalence of ANA positivity in patients with advanced or prolonged disease was higher than those with early stages or short durations. There was no correlation with drug therapy.

The blood vascular bed, perivascular space and intercellular space of the rat parathyroid gland were studied using scanning electron microscopy of vascular casts, freeze-cracked tissue samples, and NaOH-digested tissue blocks. The findings were supplemented by transmission light and electron microscopy of iron colloid-treated or enzyme-digested tissue sections. The rat parathyroid gland contained a rich network of capillaries. These capillaries were surrounded by marked pericapillary spaces which were demarcated by basal lamina of both capillaries and parenchymal cells. The pericapillary spaces contained numerous collagen fibrils, and issued many crista-like projections which ran deep into the sheets of parenchymal cells. The intercellular spaces of parenchymal cells contained neither basal lamina nor collagen fibrils. The surfaces of the parenchymal cells showed strong negative charging, and maintained the intercellular spaces. The luminal surfaces of the capillary endothelium also showed strong negative charging, and maintained the capillary lumen.

Epithelioid hemangioendothelioma is a relatively rare lesion. Although its histogenesis has been well described, its immunohistochemical characteristics remain controversial. A case of epithelioid hemangioendothelioma of the soft tissue of the right leg in a 67-year-old Chinese woman is reported. Histologic findings of intracytoplasmic lumina in the tumor cells and positive immunostaining for vimentin, factor VIII-related antigen. CD34 and Ulex europaeus agglutinin 1 (UEA-1) were obtained, demonstrating differentiation of the tumor cells to endothelial cells, although staining for antibodies to cytokeratins AE1/AE3 and CAM5.2 was weak. CD34 as well as Factor VIII-related antigen is a useful marker of endothelial differentiation in this tumor. A review of the literature is also presented.

<P>Reed-Sternberg cells (RS cells) of Hodgkin's disease (HD) are frequently infected with Epstein-Barr virus (EBV) and express EBV-encoded nonpolyadenylated RNA transcripts (EBER)-1. EBV latency has been classified into three distinct forms: Latency I, expressing only one of the latent proteins, EBV nuclear antigen (EBNA)-1, latency II, coexpressing EBNA-1 and LMPs, and latency III, expressing all latent viral proteins. RS cells express LMP-1 in addition to EBNA-1 and are considered to be EBV latency II frequently encountered in nasopharyngeal carcinoma. We examined 13 cases of EBV-infected HD by combined EBER-1 in situ hybridization and immunostaining for LMP-1. All of the RS cells expressed EBER-1, but a substantial number of EBER-1+ RS, cells were negative for LMP-1. The percentage of LMP-1+ RS cells out of EBER-1+ RS cells varied from 7% to 100% (average 69%). In this study, we showed that all EBV-infected RS cells were not restricted to latency II, and some belonged to latency I.</P>

<P>Spheroid cultures of human hepatoblastoma cells (HuH-6 line) were established by rotating 3 x 10(6) cells/3 ml culture medium in 25-ml Erlenmeyer flasks on a gyratory shaker. The size of the spheroids rapidly increased until 4 days of culture, and thereafter their size gradually increased until 8 days of culture. A considerable amount of lactate dehydrogenase (LDH) was detected in the culture medium at 24h after seeding because of cell damage by subculturing, but thereafter the amount released was small, indicating that the spheroids were in healthy condition. Albumin production, one of the differentiated functions of hepatocytes, was higher in spheroid cultures than in monolayer cultures. Using this spheroid culture model, the cytotoxic effects of alcohols on HuH-6 cells were studied by measuring the activity of LDH released in the medium from damaged cells. The results indicate that the increasing order of toxicity of the alcohols was as follows: methanol < ethanol < propanol.</P>

<P>Normal human fibroblasts have a finite proliferative capacity in vitro. Thus, immortalization of human cells is associated with cellular aging. We have established an immortalization-sensitive cell line from fibroblasts of Wilms' tumor patients which have a partial deletion of chromosome 1 1p. This cell line was easily immortalized by introducing SV4OT. By differential hybridization using both SV4OT-introduced crisis cells and young cells, we cloned a gene that was highly expressed in 1 1p-cells at the time of the crisis and named this gene C-1. Nucleotide sequence analysis of C-1 revealed that it contains a helix-loop-helix domain, indicating that it may be a transcription factor. Expression of the C-1 gene was transiently induced early in the G0-to-S phase transition in two normal human (OUMS-24 and HSF-412) and a non-tumorigenic immortal human (OUMS-24F) fibroblast cell lines, while the other immortal SUSM-1 cells highly expressed the C-1 gene in the middle G1 phase. These results suggest that the C-1 gene product may function as a transcription factor related to the cell cycle.</P>

To elucidate the latent state and reactivation of Epstein-Barr virus (EBV) in non-neoplastic lymphoid lesions, we investigated 144 non-neoplastic lymphoid lesions by in situ hybridization (ISH) to detect the expression of EBV-encoded small RNAs (EBER)-1 and BCRF-1 and by immunostaining for latent membrane protein (LMP)-1 and ZEBRA. ISH for EBER-1 detected EBER-1-positive cells (EPC) in 31 of the 144 examined lesions (22%). EPC were detected in 4 of 49 cases of nonspecific lymphoid hyperplasia, in 16 of 20 abscess-forming granulomatous lymphadenitis (AFGL), 5 of 25 Kikuchi's disease, and in 3 of 3 infectious mononucleosis. LMP-1 was expressed in 6 of 124 non-neoplastic lymphoid lesions (4.8%). LMP-1-positive cells were observed in 6 of the 31 EBER-1-positive cases (19%). EPC were detected significantly more frequently in LMP-1- and ZEBRA-positive specimens than in the LMP-1- and ZEBRA-negative specimens. BCRF-1 was expressed in 4 of 11 cases examined: 2 of 3 AFGL, 1 of 2 Kikuchi's disease, and in the 1 case of atypical lymphoid hyperplasia. This study suggests that Epstein-Barr virus is prevalent and can be reactivated in the lymph nodes effaced by destructive inflammation, such as AFGL. Such inflammation may provide a local milieu that is conducive for EBV to enter the lytic cycle.

Many neurons in the adult rat cingulate cortex possess perineuronal sulfated proteoglycans detectable with cationic iron colloid and aldehyde fuchsin, or cell surface glycoproteins reactive to lectin Vicia villosa or soybean agglutinin. The perineuronal sulfated proteoglycans develop three to four weeks after birth. The cell surface glycoproteins develop at earlier stage or two to three weeks after birth. Dark or active neurons begin to appear three to four weeks after birth. These findings indicate that the brain matures after birth or during weaning period.

To clarify the relation between systemic and cutaneous vascular endothelial injury in progressive systemic sclerosis (PSS), we examined thrombomodulin (TM) expression in PSS skin lesions immuno-histopathologically and compared it with plasma soluble TM levels measured by specific enzyme-linked immunosorbent assay. The plasma soluble TM level in PSS patients was significantly higher than that of normal controls and was as high as the levels of SLE patients. In relation to disease activities, the plasma TM levels of sclerotic phase PSS patients were significantly higher than that of atrophic phase PSS patients. The plasma samples with anti-Scl-70 antibody showed a high TM level than samples with anti-centromere antibody or anti-RNP antibody. Barnett's types or systemic corticosteroid treatment did not affect the TM level. Histopathologically, the dermal endothelial TM expression significantly increased in the sclerotic skin and moderately increased in the non-sclerotic skin of PSS compared with that of normal control skin. In addition, immunoreactive TM expression in the epidermis also increased in PSS. Disease activity-dependent elevation of plasma TM levels and immuno-histopathological expression of TM suggested generalized endothelial and epidermal cell involvement in PSS, and compensation in part by overproduction of TM by endothelial cells.