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Effects of mesenteric nerve (MN) stimulation on the electrophysiological behavior of myenteric neurons in the guinea pig ileum were investigated with intracellular recording techniques in the myenteric flaps innervated with mesenteric nerves. MN stimulation at 0.11-6 Hz evoked fast excitatory postsynaptic potentials (EPSPs) in 6 myenteric neurons (2 Type 2/AH, 3 NS and 1 Type 1/S cells) and rarely evoked antidromic soma spike potentials in 3 myenteric neurons. Fast EPSPs were abolished by hexamethonium. Slow EPSPs evoked by MN stimulation (Takaki and Nakayama (1988) Brain Res., 442, 351-353) were also obtained in 5 Type 2/AH neurons and were irreversibly abolished by superfusion with capsaicin 10 microM. It is, therefore, likely that fast EPSPs mediated by nicotinic cholinergic receptors are due to stimulation of the vagus nerve and slow EPSPs are mediated by a release of substance P at axosomatic synapses due to antidromic activation of the capsaicin-sensitive sensory nerves.

We have attempted to clarify the characteristics of monoclonal antibodies (MAbs) detecting lymphocyte subsets in fixed materials. We examined by means of flow cytometric technique influences of fixatives and reactivity with malignant lymphomas (MLs). Specific markers for T-cells were UCHL1 and OPD4, which reacted especially with helper/inducer T-cells. MT1 recognized almost all of T-cells from peripheral blood and tonsils, but reacted with a part of B-MLs. As for B-cell markers, L26 was the most reliable marker for B-MLs. L26 and MB1 antigens could not be detected on living cells flow cytometrically. LN1 reacted with a part of T-cells as well as B-cells, but fluorescent intensity of the former was apparently stronger than that of the latter. Although LN2 antigen was located mainly in the cytoplasm close to the nuclear membrane immunohistochemically, it could be detected on living cells flow cytometrically. LN2 positive cells belonged to B-cells in peripheral blood and tonsils. When fixed for relatively short time, B5 and buffered formalin were better for examining MAbs than non-buffered formalin and ethanol.

The effects of laminin (LAM) and collagen type I (C-I) on human hepatoblastoma (HuH-6) and hepatoma (HuH-7) cell lines were investigated. C-I was superior to LAM in supporting the attachment of the cells, especially of HuH-6, to plastic surfaces. No effect of LAM and C-I on cellular morphology was recognizable by phase contrast microscopy. By scanning electron microscopy (SEM), much more microvilli were found on the cell surface of HuH-6 on LAM substrate than on C-I substrate. In HuH-7 cells, however, these microvilli were rarely found on either LAM substrate or C-I substrate. The gel profile of the proteins secreted by HuH-6 and HuH-7 cells was not affected by the culture substrate except for the major band, though the amount of alpha-fetoprotein (AFP) secreted was larger when the cells were cultured on LAM substrate than on C-I substrate. These results indicate that the ability of LAM or C-I to enhance attachment is different from that to enhance AFP production or microvilli expression in HuH-6 cells and probably in HuH-7 cells.

Meth A-fibrosarcoma bearing BALB/c mice were subjected to selected splenic irradiation (2.0-4.0 Gy) on days 7 and 14 of tumor growth. Tumor growth was recorded by serial measurement. Irradiation given on day 7 caused regression of tumor, but irradiation given on day 14 did not show tumor regression. Antitumor activity in the Winn assay was detected in spleen cells 3 days after irradiation, but was not detected 7 days after. The cell surface phenotypes were analyzed on days 3, 7 and 14 of splenic irradiation using monoclonal antibodies (anti-Thy1.2 antibody, anti-Lyt1 antibody, anti-Lyt2 antibody, anti-L3T4 antibody) by flow cytometry. Thy 1.2, Lyt1, and L3T4 cells were increased on day 3 of splenic irradiation, but were not on days 7 and 14. Lyt2-cells did not show increase on days 3, 7 and 14. It was possibly suggested that selected splenic irradiation induced tumor regression was caused by the ability of irradiation to preferentially eliminate suppressor T cells, thereby allowing effector T-cells to become relatively dominant.

The effects of uridine(UR) on the cell-killing activity of cytosine arabinoside(ara-C) against human leukemic cells, MOLT-4, and on ara-C accumulation in cells were studied. The 50% lethal dose(LD50) of ara-C as determined by clonogenic assay was decreased to 5.0 x 10(-8) mol from 9.0 x 10(-7) mol after 3 days exposure to 10(-3) mol of UR. The accumulation of 3H-ara-C at 24 and 48 h was significantly increased in culture medium containing 10(-8) mol of 3H-ara-C and 10(-3) mol of UR (5,129 +/- 123.5 vs 2,554 +/- 115.5 cpm/10(5) cells at 24 h, p less than 0.01, and 5,772 +/- 123.2 vs 1,372 +/- 51.8 cpm/10(5) cells at 48 h, p less than 0.01). It is noteworthy that cell-killing activity of ara-C against human leukemic cells was enhanced by the combination with a nucleoside(UR), but not with antileukemic agents.

Twenty-four patients with rheumatoid arthritis (RA) and 20 normal controls were examined for the ability of their peripheral blood B cells to produce interleukin 1 (IL-1) with or without lipopolysaccharide (LPS). B cells were purified from peripheral blood by negative selection methods (i.e., removal of adherent cells and sheep red blood cell rosette-forming cells, followed by treatment with monoclonal antibodies (OKT3 and OKM1) and complement). The amount of IL-1 in B cell culture supernatants (SN) was measured by thymocyte and fibroblast proliferation assays and an enzyme-linked immunosorbent assay for IL-1 alpha and beta. As a group, cultured B cells from patients with RA, both spontaneously and when stimulated with LPS, produced higher levels of IL-1 than those from normal controls. IL-1 production by RA B cells with LPS had a weak but positive correlation with disease activity. Moreover, RA B cell culture SN with elevated levels of IL-1 had a synergistic effect on the growth of anti-human IgM (anti-mu) stimulated B cells. In separate experiments, the growth of RA B cells was significantly promoted by IL-1 beta both with and without anti-mu stimulation. These results suggest that B cell-derived IL-1 may be involved in the B cell clonal expansion of RA through its own activity as a B cell stimulatory factor.

We examined the effect of fetal calf serum (FCS) on meiotic division, subsequent fertilization, and first cleavage to the 2-cell stage of rat oocytes during in vitro maturation. FCS had no effect on the nuclear progression from dictiate to metaphase of the second maturation in vitro and, FCS had no effect on the first cleavage to the 2-cell stage of fertilized oocytes. However, FCS efficiently increased penetration rate of oocytes and shortened the time required for dissolution of the zona pellucida by alpha-chymotrypsin. These results showed that FCS did not affect cytoplasmic maturation necessary for oocytes to develop to the 2-cell stages. We found that FCS only affects the zona pellucida and does not affect the nucleus or cytoplasm of rat oocytes. FCS may prevent hardening of the zona pellucida.

Ki-67 is a commercially available mouse monoclonal antibody (MoAb), which reacts with a nucleolar antigen (the Ki-67 antigen) expressed in proliferating eukaryotic cells. The author examined the precise localization of the Ki-67 antigen in C-6 cells using immunohistochemical and immunoelectron microscopic methods and estimated the proliferative activity of human brain tumors in situ. Positive nucleoplasmic reactions (early G1 phase) and nucleolar staining (late G1 phase) were observed. The cells showed very weak positive reactions in only one or two nucleoli (S phase) and multiple spicule reactions in the nucleoplasm (G2 phase). During the mitotic phase, the Ki-67 antigen was stained on the surfaces of all chromosomes and finely dispersed in the cytoplasm. By immunoelectron microscopic study, positive reactions were observed on the granular and dense fibrillar components. Therefore, the Ki-67 antigen seems to participate in the processing and assembly of preribosomal particles. In human brain tumors, the Ki-67 score (positive cells/total neoplastic cells), ranging 0 to 36.7%, correlated well with the histopathological grade of malignancy of the tumor. These findings suggest that immunohistochemical staining with the MoAb Ki-67 can be used as a convenient procedure for the simple evaluation of the proliferative activity of brain tumors.

The establishment of a model system of neoplastic transformation of normal human cells has been attempted with a chemical carcinogen, 4-nitroquinoline 1-oxide (4NQO). In the course of these experiments, it was noticed that immortalization of human cells is a multi-step process involving several mutational genetic events. Thus, chromosomal changes which occurred during the process of immortalization of human fibroblasts were examined. To accomplish immortalization, fibroblasts obtained from an embryo were repeatedly treated with 10_-6M4NQO from primary culture to passage 51 (59 treatments in total). Before immortalization, some chromosomes (especially, chromosomes 2, 6, 8, 10, 11, 12, 15, 19, and 20), were lost at a relatively high frequency. After immortalization, the chromosomes distributed so broadly in the triploid to hypotetraploid region without a distinct modal number or without marker chromosomes that it was difficult to identify the specific chromosomes related to the immortalization of human cells. No specific structural chromosomal changes were detected. Although the significance of such chromosome changes in relation to immortalization is not clear, the loss of some specific chromosomes suggests that genes which are involved in cellular aging and which suppress immortalization may have been lost in the immortalization process.

Tissue PIVKA-II was examined in 32 hepatocellular carcinomas and 2 metastatic liver tumors using indirect immunofluorescence, and the results were compared with the size, histological grading and serum PIVKA-II level. The specificity of this method was confirmed by the disappearance of reactivity in PLC/PRF/5 cells after the addition of vitamin K to the culture medium. Positive PIVKA-II staining was observed as a clustered or a single cell pattern only in the HCC nodules, but not in the surrounding cirrhotic tissue. PIVKA-II staining was observed in all HCC groups regardless of histological grade. There was no relationship between PIVKA-II staining and the size of HCC. PIVKA-II was detected immunohistochemically even in small HCC of patients whose plasma PIVKA-II levels were below the detection limit. These results suggest that PIVKA-II production is a specific phenotype of HCC regardless of its histological grading and demonstrate that this immunofluorescent PIVKA-II staining is more sensitive and useful than plasma PIVKA-II assay for the diagnosis of HCC.

To clarify the immunological function of 'M' (microfold or membranous) cells in the large intestine, we examined the expression of intercellular adhesion molecule-1 (ICAM-1) and HLA-class II antigens immunohistochemically in M cells and follicle-associated epithelia (FAE) covering isolated lymphoid follicles of the human colon in comparison with their expression in Peyer's patches of the small intestine. In Peyer's patches of the small intestine, ICAM-1 was not expressed on the epithelial cells covering the lymphoid follicles, but their cell surfaces were stained positively for HLA-DR. In contrast, colonic M cells expressed ICAM-1 on their cell surfaces but were negative for HLA class II antigens. By immunoelectron microscopy, ICAM-1 was seen to be distributed on the surface of microfolds, on the membranes of apical vesicles and on part of the basolateral plasma membranes of M cells, but was not expressed on adjacent FAE. These findings imply that the M cells in the colon and in Peyer's patches have different immunological roles. In addition, identification of ICAM-1 expression on the colonic M cells should help elucidate the pathogenesis of some inflammatory colonic diseases which appear to start in the lymphoid follicles of the colonic mucosa.

A persistent problem in orthotopic liver transplantation is primary nonfunction (PNF) of the hepatic allograft. In an attempt to reduce the incidence of graft failure, the feasibility of pretransplant assessment of graft viability was investigated by 31P nuclear magnetic resonance (NMR) spectroscopy. The level of adenosine triphosphate (ATP) was measured as an indicator of liver function by 31P NMR spectroscopy after a 30 min normothermic reperfusion following cold-storage in University of Wisconsin (UW) solution. The mean +/- SD beta-ATP/Pi ratio after preservation for 0, 12, 24 or 48 h was 1.40 +/- 0.34, 0.85 +/- 0.27, 0.64 +/- 0.14 and 0.38 +/- 0.09, respectively. Significance was observed between 12h and 24h and between 12h and 48h of preservation. These results correlated well with the morphological changes in endothelial cells and sinusoidal lining cells examined by transmission electron microscopy. It is suggested strongly that microcirculatory disturbances due to endothelial cell injury impairs the recovery of ATP levels after reperfusion, and that ATP determination by 31P NMR spectroscopy, as a non-invasive modality, may help in the prediction of PNF after liver transplantation.

The presence of high-risk types of human papillomavirus (HPV) 16, 18 and 33 in cell lines established from several malignancies including 5 of cervical cancer and 6 of head and neck cancer was studied. HPV DNA, either type 16 or 18, was detected by polymerase chain reaction, and by Southern blot hybridization in all of the cell lines derived from cervical cancers. The hybridization patterns of HPV DNA after endonuclease digestion differed among cell lines, suggesting that all of these cell lines were independent isolates. Accordingly, high-risk types of HPV DNA seem to be ubiquitous in cervical cancer. HPV DNA was not detected in the cell lines derived from head and neck cancers or from any other malignancies besides cervical cancer in this study.

The antitumor effects of indomethacin and interleukin 2 (IL-2) were studied in C3H/HeJ mice inoculated with MH134 hepatoma cells. Combined treatment with indomethacin and IL-2 augmented natural killer (NK) cells in mice with MH134-induced peritoneal carcinomatosis, and the survival of the treated mice was significantly longer than the non-treated mice. In animals with subcutaneous MH134 tumors, the combined therapy with indomethacin and IL-2 significantly suppressed tumor growth and induced complete regression of the tumor in three out of five mice. These results suggest that indomethacin and IL-2 therapy could be effective on human gastrointestinal cancer cells as well.

Localization of the glycosaminoglycans (GAG) was examined in the synovial membranes of patients with osteoarthritis under light microscopy using a fine cationic colloidal iron staining method combined with enzymatic digestion. Our staining method was very useful for demonstrating the difference in the localization of GAG in regions of the inflammatory site in the osteoarthritic synovial membrane. Hyaluronic acid was mainly located in connective tissues in the surface intercellular and perivascular spaces, chondroitin sulfate A/C in the highly fibrous part of and connective tissue around blood vessels, dermatan sulfate (chondroitin sulfate B) in the subsurface interstitium and vascular endothelial cells and heparan sulfate in part of vascular endothelial cells. No keratan sulfate was detected. GAG is reported to have an important role in cell movement, adherence and aggregation in the inflammatory sites. These findings should be useful for understanding the role of GAG in physiological and pathologic processes of secondary synovitis.

Examination was made of the in vitro response of human peripheral blood mononuclear cells (PBNMCs) to phytohemagglutinin (PHA) following treatment with varicella zoster virus (VZV) or herpes simplex virus type 1 (HSV 1). Cell proliferation was determined by colorimetric assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide. The response to PHA was depressed in all cases by virus infection of PBMNCs prior to PHA treatment. When the infection with the viruses was after PHA treatment, PHA response differed. For VZV infection, the response increased in four out of six samples, but was reduced in the other two. The response to PHA was depressed in all six samples by HSV 1 infection.

Fas antigen (ag) is a cell surface protein known to trigger apoptosis in a variety of cells upon specific antibody binding. On the other hand, Bcl-2 protein, an oncogene product located at the mitochondrial inner surface, prolongs cell survival by blocking apoptosis. In this study we examined the expression of Fas ag and bcl-2 protein in 17 cases of hepatocellular carcinoma (HCC) to determine their role on HCC. By flow cytometric analysis, mean (SD) value of the expression of Fas ag on hepatocytes derived from normal liver, diseased liver (chronic hepatitis or liver cirrhosis) and HCC was 5.8 (4.7)%, 10.3 (6.9)%, and 24.0 (18.2)%, respectively. Fas ag expression on hepatoma cells was significantly greater than normal and diseased liver cells. The expression of Bcl-2 protein in normal liver, diseased liver and HCC was 4.3 (8.5)%, 0.8 (2.5)% and 2.1 (3.4)%, respectively, and the difference was not significant. These results suggest that induction of apoptosis may be a possible therapy against HCC.

It has previously been confirmed that the guinea pig has aggregations of 10-20 lymphoid follicles at the junction of the nasal cavity and the nasopharyngeal duct. The vascular architecture of this nasal-associated lymphoid tissue (NALT) was studied by the corrosion cast/scanning electron microscope method. The NALT was supplied by branches of the inferior nasal artery. These afferent arterial branches gave off arterioles to the follicles and the interfollicular regions, where the arterioles ramified into capillaries. Some of these arterioles reached the subepithelial region to form a single-layer dense capillary network. The subepithelial capillaries gathered into short collecting venules, which in turn drained into high endothelial venules (HEV) in the interfollicular region. The HEV, which also receives tributaries from the follicular and interfollicular capillary plexuses, descended in the interfollicular regions and finally flowed into the efferent veins at the bottom of the NALT. Indentations impressed by high endothelial cells (HEC) were prominent on the surface of the HEV casts, and their frequency was larger in the upper course or segments than in the lower. This suggests that the incidence of HEC in the upper segments is higher than in the lower segments, and these findings are consistent with the hypothesis that some substances which are taken up into the subepithelial capillaries and transported to the venules induce differentiation and maintain of HEVs.

The whole body including extended processes of Ito's fat-storing cells was observed by scanning electron microscopy in rat liver injured with lithocholic acid (LCA). Necrotic foci developed in the midlobular zone 48 h after LCA administration. Demonstration of Ito cell bodies around the foci was probably facilitated by easy detachment of hepatocytes from Ito cells. The body and the processes were located mainly between the sinusoidal endothelium and hepatocytes; sometimes they were between hepatocytes. Ito cells often were proximate to collagen fiber bundles and sometimes were attached to them. The cell body was flatly round or elliptic, 7 to 12 micron in diameter. Its surface was finely undulated with microvillous projections about 0.1 micron in length. Branching patterns of the processes resembled a fern-leaf mantling the sinusoidal endothelium. The trunks of the processes were about 2 micron in diameter and 20-30 micron in length. These processes tapered, branching into thinner processes, with the most peripheral being 0.1 micron in diameter. Ito cells and their branching processes likely strengthen sinusoidal walls and control blood flow in the sinusoids.