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Effects of antioxidants, such as superoxide dismutase, vitamin C, vitamin E, 4-(0-benzylphenoxy)-N-methylbutylamine hydrochloride (bifemelane), and selenite on survival of adult rat hepatocytes were examined under normoxic and hyperoxic conditions in serum-free primary culture. The tested antioxidants, except for vitamin C, significantly increased the survival rate of hepatocytes under the normoxic condition (under air). Thus, even the normoxic culture condition is hyperoxic for hepatocytes. Elevation of oxygen tension (40% O2) caused severe morphologic degeneration of hepatocytes and remarkable decrease in the survival rate of the cells. Addition of the antioxidants effectively protected hepatocytes from the morphologic degeneration, and significantly improved the survival of the cells under the hyperoxic condition. These findings indicate that the antioxidants can maintain the long-term survival of hepatocytes in serum-free primary culture.

Hematoxylin and eosin (H-E) stained liver sections of 47 autopsy cases of hepatic malignancies were examined. There were 43 cases of hepatocellular carcinoma (subtypes of 30 trabecular, 7 solid, 5 pseudoglandular, and one scirrhous carcinoma), 3 of cholangiocellular carcinoma and one of mixed carcinoma. After immunohistochemical staining, benign hepatocytes reacted positively with anti-epithelial membrane antigen (EMA). Hepatocellular carcinoma cells reacted more weakly than benign hepatocytes. It was noted that the microtubular structure, which could not be demonstrated even by alcian blue or cationic ferric hydroxide colloid stabilized with cacodylate (Fe-CaC), was clearly detected with anti-EMA. The EMA-positive microtubular structures may indicate terminal cholangiolar differentiation. Based on EMA, seven more cases formerly classified as hepatocellular carcinoma by H-E were reclassified as mixed carcinoma, totaling eight (17.0%). The histologic classification of "mixed carcinoma" has been 1.5 to 2.0% of primary liver cancers in Japan, but we suggest there may be more cases of "mixed carcinoma" identified in the future. In conclusion, we emphasize that EMA staining is useful for more accurate classification of hepatic tumors.

A 34-year-old woman infected with human T cell leukemia virus type-I(HTLV-I) with recurrent thrombocytopenia and various autoantibodies is described. The platelet counts fluctuated between 1.3 x 10(4)/microliters and 14.8 x 10(4)/microliters without any medical treatment, and thrombocytopenia improved with a decrease of platelet-associated IgG (PA-IgG). Autoantibodies such as rheumatoid factor, antinuclear factor, anti-Sm, anti-RNP and anti-SSA antibodies were also recognized. Marker analysis of peripheral mononuclear cells showed an increase in the proportion of CD 25+ cells, CD 3+ HLA-DR+ cells, CD4+ HLA-DR+ cells and CD8+ HLA-DR+ cells. The recurrent thrombocytopenia and development of various autoantibodies in this HTLV-I carrier are speculated to be due to the alteration of B cell functions by T cells infected with HTLV-I.

Proportional changes of lymphocyte subsets in the peripheral blood were monitored by two-color flow-cytometry in seven leukemia patients who had received allogenic bone marrow transplantation (BMT). Lymphocyte counts, and proportions of T and B-cells returned to normal ranges between the 2nd and 12th months after BMT. Activated T-cells prominently increased after BMT, and the values gradually returned toward normal. As to lymphocyte subsets, the proportions of CD 4+ cells had remained low, while those of CD 8+ cells high for a whole observation period after BMT. The changes of CD 4+ cells were caused by the decrease of suppressor-inducer T-cells (CD 4+ Leu 8+). High proportion of CD 8+ cells was mainly associated with increased suppressor T-cells (CD 8+ CD 11+). Among natural killer (NK) cells, highly active NK cells (CD 16+ CD 57-) markedly increased shortly after BMT, and gradually returned to normal. CD 16 -CD 57+ NK cells increased beyond normal ranges after the 2nd month. The incidence or degree of acute and chronic graft-versus-host diseases (GVHD) did not correlate with the changes of any lymphocyte subsets. The present results suggest that the increase of activated T-cells shortly after BMT reflects lymphocyte reconstitution. The prolonged immune deficiency after BMT might be related to either deficient expression of homing receptor (Leu 8 antigen) on CD 4+ cells or increased suppressor T-cells (CD 8+ CD 11+). In addition, the early increase of NK cells after BMT may compensate for the immune deficiency in BMT patients.

Wheat germ agglutinin binding to a rat hepatoma cell line dRLa 74 treated with concanavalin A was studied. It increased depending on the concanavalin A concentration in the culture medium. The cells exhibited about twofold increase in wheat germ agglutinin-binding when pretreated with 50 micrograms/ml of concanavalin A for 48 h. The wheat germ agglutinin binding sites were shown to be localized at the cell surface by lectin-histochemistry. Wheat germ agglutinin blotting of microsomal membrane proteins showed a broad wheat germ agglutinin-reactive band with an apparent molecular weight of 90 to 100 kDa. Loss of wheat germ agglutinin binding to dRLa 74 cells and the glycoprotein after neuraminidase treatment suggested that wheat germ agglutinin reacted with cell surface sialyl residues of dRLa 74 cells. The induced change was reversible. Increased wheat germ agglutinin binding returned to the pretreatment level when the concanavalin A-treated cells were subcultured in the absence of concanavalin A. These observations suggest that environmental factors interacting with tumor cell surface sugar moieties may induce reversible epigenetic changes on cell surface carbohydrate structures.

The immunologic mechanisms mediated by anticolon antibodies have been suggested for the injury of colonic mucosa in ulcerative colitis (UC). For the understanding of pathogenetic relevance of the anticolon antibody in UC, we examined the class and the subclass of the anticolon antibody reactive to rat colonic epithelial cells in sera from 10 patients with UC immunohistochemically by an indirect immunoperoxidase method. We also examined the distribution of the antigen recognized by the anticolon antibody by immunoelectron microscopy. The antibody reactive to the rat colonic epithelial cell was detected in 2 of the 10 patients, and the class and subclass of the antibody was mainly IgG2. The antigen recognized by the anticolon antibody was located on the apical membrane of the colonic epithelial cells and mucous substances of the goblet cells. These findings suggest that the anticolon antibody detected in this study is inadequate to cause the colonic mucosal injury by activating complements or mediating antibody-dependent cellular cytotoxicity. A potential pathogenetic role of the anticolon antibody in UC remains to be established.

Pressure distribution patterns of the seating interface on the multi-cell air cushion (ROHO High Profile) of 36 adults with spinal cord injury (SCI) (Neurological level Th3 -L1) were measured at different air pressure levels by a pressure mat measurement system. Stress distribution relative to the inflated air pressure in the air cushion on the patients' wheelchairs was analyzed to determine the appropriate inflated air pressure of the cushion for patients. The maximum pressure points in all subjects were at the areas of the ischial tuberosities (82 to 347 mmHg). The optimal reduction in interface pressure at the ischial tuberosities was obtained just before bottoming out. The cushion air pressure at that point was between 17 and 42 mmHg, and correlated well to body weight (r = 0.495, P = 0.0021). In contrast, the maximum pressure levels did not correlate to body weight or the Body Mass Index (BMI). Pressure at the ischial area could be reduced, but not eliminated, by adjusting the air pressure. The maximum pressure levels seemed to be related to the shape of the buttocks, especially the amount of soft tissue, and exceeded the defined threshold for pressure ulcers (> 80 g/cm2).

Head injury or hemorrhagic cortical infarction results in extravasation of blood and breakdown of red blood cells and hemoglobin. Iron liberated from hemoglobin, and hemoglobin itself, are associated with the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS have been demonstrated to be involved in the mechanism of seizures induced by iron ions in the rat brain, an experimental animal model for posttraumatic epilepsy (PTE). ROS are responsible for the induction for peroxidation of neural lipids, i.e., an injury of neuronal membranes, and also could induce disorders in the excitatory and inhibitory neurotransmitters. Antioxidants, such as a phosphate diester of vitamin E and C (EPC-K1) and antiepileptic zonisamide, have been known to prevent the epileptogenic focus formation, or to attenuate seizure activities in the iron-injected rat brain. Natural antioxidants, such as alpha-tocopherol, and condensed tannins, including (-)-epigallocatechin and (-)-epigallocatechin-3-O-gallate, adenosine and its derivative, melatonin, uyaku (Lindera Strychnifolia), fermented papaya preparations, Gastrodia elata BI., and Guilingji, have been demonstrated to scavenge ROS and/or RNS and to be prophylactic for the occurrence of epileptic discharge in the iron-injected rat brain.

Hepatocyte growth factor (HGF) is a multifunctional factor implicated in tissue regeneration, wound healing, and angiogenesis. HGF was initially thought to be liver-specific, but it has become clear that HGF acts on alveolar type II cells and bronchial epithelial cells. This study was conducted to determine the role of HGF in pulmonary ischemia in a rat model. The first increase of the plasma HGF level was noted 30 min after pulmonary ischemia, and reached a peak at 12 h. Real-time reverse transcription polymerase chain reaction (Real-time RT-PCR) revealed that the HGF messenger RNA (mRNA) expression in the injured left lung was markedly increased at 1, 6, and 12 h after pulmonary ischemia (P < 0.05). The interleukin-1beta (IL-1beta) mRNA expression, one of the inflammatory cytokines which induces HGF expression, was markedly increased at 1 h in the injured left lung (P = 0.0007). Therefore, we considered that HGF might be mainly induced by paracrine mechanisms in pulmonary ischemia. In conclusion, we have shown that the expression of HGF was induced in pulmonary ischemia, and may be a useful biological marker for the early diagnosis.

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by dopaminergic neuron-specific degeneration in the substantia nigra. A number of gene mutations and deletions have been reported to play a role in the pathogenesis of familial PD. Moreover, a number of pathological and pharmacological studies on sporadic PD and dopaminergic neurotoxin-induced parkinsonism have hypothesized that mitochondrial dysfunction, inflammation, oxidative stress, and dysfunction of the ubiquitin-proteasome system all play important roles in the pathogenesis and progress of PD. However, these hypotheses do not yet fully explain the mechanisms of dopaminergic neuron-specific cell loss in PD. Recently, the neurotoxicity of dopamine quinone formation by auto-oxidation of dopamine has been shown to cause specific cell death of dopaminergic neurons in the pathogenesis of sporadic PD and dopaminergic neurotoxin-induced parkinsonism. Furthermore, this quinone formation is closely linked to other representative hypotheses in the pathogenesis of PD. In this article, we mainly review recent studies on the neurotoxicity of quinone formation as a dopaminergic neuron-specific oxidative stress and its role in the etiology of PD, in addition to several neuroprotective approaches against dopamine quinone-induced toxicity.

Epstein-Barr virus (EBV)-related herpesvirus (Si-IIA-EBV) was serially transmitted for 3 passages from rabbit to rabbit of the opposite sex by blood transfusion, which subsequently induced virus-associated rabbit lymphomas. The virus could be transmitted by transfusion with 15-20 ml of whole blood (7/7) or irradiated blood (1/6) from the EBV-related virus-infected rabbits, but there was no transmission with transfusion of cell-free plasma (0/6) from the infected rabbits. Passive anti-EBV-VCA IgG (x 20 approximately x 10) titers decreased during the first 1-2 weeks in the transfused rabbits. The virus-transmitted rabbits showed a gradual increase in antibody titers ranging from peak titers of x 640 to x 2560 after 3 weeks of transfusion. The recipient origin of malignant lymphoma that developed in the first rabbit transfused by infected blood was confirmed by chromosomal analysis. This rabbit model thus shows that EBV-related herpesvirus is serially transmissible by blood transfusion and that transmission can not be completely prevented by irradiation of blood, but removal of blood cells is the best way to prevent transmission of EBV-related virus. Therefore, this animal model provides a convenient in vivo system for studies of the prevention and therapy of transfusion-related transmission of EBV and EBV-associated lymphoproliferative diseases in immunocompromised human beings.

We present a case of a primary advanced gastric tumor that was composed of 2 different pathological components: small cell carcinoma and moderately-differentiated adenocarcinoma. The patient was still alive four years after the surgery was performed, without recurrence. A large part of the tumor consisted of a diffuse sheet of small cell carcinoma, which transitioned into another small portion consisting of moderately-differentiated tubular adenocarcinoma components. Therefore, this case raised the possibility that small cell gastric carcinoma may originate from totipotential stem cells of the stomach. Although small cell carcinoma progresses aggressively, and patients with it have an extremely poor prognosis, this patient recovered uneventfully after the surgical resection, and has remained in good health, without any recurrences.

Because of the many superficial similarities between the immune system and the central nervous system, it has long been speculated that somatic DNA recombination is, like the immune system, involved in brain development and function. To examine whether or not the V(D)J recombination signals of the immune system work in an in vitro neural differentiation model, the P19 mouse embryonal carcinoma cell line was transfected with a reporter gene that is designed, when rearranged, to express bacterial beta-galactosidase, which was previously reported to exhibit somatic DNA recombination in the transgenic mouse brain. The cloned cells were then induced into neural cells by retinoic acid treatment. This neural induction treatment resulted in the cloning of a P19 cell line that showed a high incidence of beta-galactosidase-positive cells. Most of these beta-galactosidase-positive cells were immunocytochemically identified as either neurons, neuroepithelial cells, or astrocytes. The 5'-end sequences of the beta-galactosidase transcripts expressed in the induced cells were analyzed, and sequences were found that seemed to reflect DNA rearrangement through re-integration of the reporter gene into the host genome. However, the V(D)J recombination signals did not work in the in vitro model. These results suggested that DNA rearrangement activity though integration increased during neural differentiation of P19 cells.

Epstein-Barr virus (EBV), or human herpesvirus 4 (HHV-4), infects the vast majority of adults worldwide, and establishes both nonproductive (latent) and productive (lytic) infections. Host immune responses directed against both the lytic and latent cycle-associated EBV antigens induce a diversity of clinical symptoms in patients with chronic active EBV infections who usually contain an oligoclonal pool of EBV-infected lymphocyte subsets in their blood. Episomal EBV genes in the latent infection utilize an array of evasion strategies from host immune responses: the minimized expression of EBV antigens targeted by host cytotoxic T lymphocytes (CTLs), the down-regulation of cell adhesion molecule expression, and the release of virokines to inhibit the host CTLs. The oncogenic role of latent EBV infection is not yet fully understood, but latent membrane proteins (LMPs) expressed during the latency cycle have essential biological properties leading to cellular gene expression and immortalization, and EBV-encoded gene products such as viral interleukin-10 (vIL-10) and bcl-2 homologue function to survive the EBV-infected cells. The subsequent oncogenic DNA damage may lead to the development of neoplasms. EBV-associated NK/T cell lymphoproliferative disorders are prevalent in Asia, but quite rare in Western countries. The genetic immunological background, therefore, is closely linked to the development of EBV-associated neoplasms.

Protein transduction therapy using poly-arginine peptide can deliver the biologically active proteins. A previous study showed that 11 poly-arginine fused p53 protein (11R-p53) effectively penetrated across the plasma membrane and inhibited the proliferation of oral cancer cells. However, the intracellular half-life of the delivered protein was less than 36 h. Previous studies also showed that 2-methoxyestradiol (2-ME), an endogenous non-toxic estrogenic metabolite, induces the stabilization of the wild-type p53 protein in human cancer cells posttranscriptionally. In the present study, we examined whether 2-ME induced the stabilization of 11R-p53 and had an inhibitory effect on the proliferation of oral cancer cells. The application of 2-ME significantly enhanced the inhibitory effect of 11R-p53 on the proliferation of oral cancer cells. However, 2-ME had no effect on the intracellular half-life of 11R-p53 in oral cancer cells. Of interest is the finding that 2-ME suppressed the transcriptional activity of NFkappaB, which has an important role in tumorigenesis, but did not affect p53 transcriptional activity. These results suggest that 2-ME synergistically enhances the 11R-p53-induced inhibition of the proliferation of oral cancer cells through the suppression of NFkB transcription.

Levamisole was administered to 177 patients with gastrointestinal cancer (88 curative resection, 58 noncurative resection and 31 without resection). It was administered at a daily dose of 150 mg for three consecutive days every other week. The administration was started, as a rule, 3 days before operation. This medication was repeated as frequently as possible at least for one month. The cellular immunity and 18-month survival rate of treated and control groups were compared. Levamisole effectively improved peripheral lymphocyte blastformation against phytohemagglutinin and increased the numbers of peripheral blood lymphocytes. Levamisole caused extremely high blastformation rates, in general, enhanced PPD reactions in non-curative resection cases 7 months after operation and showed no influence upon the number of peripheral blood lymphocyte. The effect of levamisole on the 6-month survival rate was most marked in patients without resection. Increased 12-month survival rate was marked in non-curative resection cases and, to a lesser extent, curative resection cases. Patients without resection had a slightly improved 12-month survival rate. Levamisole improved the 18-month survival rate in resectable cases; however, there were no significant differences in 18-month survival between levamisole and control groups of patients not undergoing resection. The results suggest that levamisole is effective in the patients whose tumor cells have been decreased by any method.

Sera from 84 patients with chronic liver disease [CLD] (74 chronic active) and from 53 blood donors were tested immunochemically for anti-liver cell membrane antibody (LMAb). LMAb to rat liver tested by an indirect immunofluorescent technique was positive in 53.3% of CLD patients with positive HB surface antibody (HBsAb) and 40.0% of HBsAb positive blood donors. Pepsin digestion of the sera indicated that the binding between liver cell membrane and IgG was at the Fc site on the immunoglobulin. The sera with positive LMAb from HBsAb positive blood donors had elevated Clq-binding activity (Clq-BA). The LMAb to rat liver was a macro-molecular IgG (19-22S IgG) when assayed by Sephadex G-200 column chromatography and 5-40% sucrose density gradient ultracentrifugation. The results suggest that the LMAb in serum from a patient with chronic active liver disease may be an immune complex which consists of various antigens such as HB virus and its antibodies in serum.

The mechanism of cell dissociation with trypsin and EDTA was examined. Cell dissociation was possible when trypsin and EDTA were given simultaneously, when trypsin was given after EDTA treatment, but not when trypsin was given before EDTA treatment.