Production of Macrophage Migration Inhibition Factors by Virus-Infected Cell Cultures

Macrophage migration inhibitory (MIF-like) activity was demonstrated in the supernatant fluids from cultures of African green monkey kidney cells (BGM) infected with mumps virus or Newcastle disease virus. We could detect no such activity in noninfected cultures. The virus-induced activity reported here is not due to nonspecific cytotoxic material released by dead or dying cells, and it does not require cell replication for its production. Preliminary estimates of molecular weight by Sephadex G-100 chromatography revealed a broad band of activity associated with the 45,000 and 65,000 markers. These are significantly smaller than previously reported chemotactic substances from virus-infected cultures, and thus appear to represent different cell products. These MIF-like factors may be produced concomitantly with interferon. However, ultraviolet irradiation of appropriate duration abolishes the ability of viruses to induce substances with MIF-like activity while preserving the ability to induce interferon. This strongly suggests that interferon is not the agent responsible for the macrophage migration inhibition effect. The functional properties of these various cell products induced by virus infection suggest that they all may play a role in the response to virus infection in vivo.     

Nuclear accumulation of beta-catenin in intestinal-type gastric carcinoma: correlation with early tumor invasion

Mutation of the adenomatous polyposis coli gene, which is known to be an early event in the carcinogenesis of intestinal-type gastric carcinoma, leads to accumulation of beta-catenin. In addition, beta-catenin has been found to activate down stream signaling molecules in the wingless/Wnt pathway. In this study, the clinical significance of nuclear accumulation of beta-catenin was evaluated in gastric carcinoma. Immunohistochemical staining showed nuclear localization in 16 (12%) of 139 (94 intestinal-type and 45 diffuse-type) gastric carcinomas, and all 16 lesions with nuclear staining were intestinal-type adenocarcinomas. Of the 16 cases, 15 were in the early clinical stage. In the remaining case, the lesion had invaded the subserosal layer and showed strong nuclear staining at the invasive front. In 14 of the 16 cases with nuclear localization, there were no abnormal mobility shifts detected using polymerase chain reaction-single strand conformational polymorphism analysis. This was confirmed using direct sequencing analysis, which revealed the wild-type sequence in the 12 cases tested. Nuclear accumulation of beta-catenin did not correlate with lymph node metastasis or 5-year survival. These findings suggest that high intranuclear levels of beta-catenin protein play an important role in early tumor growth and may function in initiation of invasive processes in intestinal-type gastric carcinoma.     

A CASE OF GASTRIC CARCINOMA WITH MASSIVE EOSINOPHILS

This report describes a 67-year-old male with inoperable gastric cancer accompanied by marked tissue and peripheral eosinophilia without evidence of allergic disorders or parasitic infestation. Autopsy revealed an advanced gastric cancer of scirrhous type with metastases to pancreas, bone marrow, ileum, lungs, and lymph nodes. Excessive numbers of mature eosinophils were present in univolved bone marrow, liver and spleen as well as among the signet ring cell component of the cancer in either primary or metastatic sites. The primary cancer also possessed a component of tubular adenocarcinoma which was associated with only a few eosinophils. Hence, we speculate that an eosinophil mobilizing (chemotactic and/or proliferating) factor (s) was produced by the signet ring cancer cells.     

Localization of efferent neurons innervating the pharyngeal constrictor muscles and the cervical esophagus muscle in the cat by means of the horseradish peroxidase method

Following horseradish peroxidase (HRP) injection into the cephalopharyngeal muscle (CeP), the hyopharyngeal muscle (HP), the thyropharyngeal muscle (TP), the cricopharyngeal muscle (CP) and the cervical esophagus muscle (CE) of the cat, labeled neurons were identified in the nucleus retrofacialis and the rostral part of the nucleus ambiguus ipsilaterally. The rostral end of the labeled cell column was located more rostrally for CeP and HP than for TP, CP and CE. No difference was noted within the former two or within the latter three. The level of the caudal end of the labeled cell column became more caudal in the order of CeP, HP, TP and CP. The caudal end was located more rostral for CE than for TP. The neurons for CE were located more ventro-laterally than those for the other muscles.     

Analysis of 8-hydroxydeoxyguanosine 5'-monophosphate (8-OH-dGMP) as a reliable marker of cellular oxidative DNA damage after gamma-irradiation

In order to improve 8-hydroxyguanine (8-OH-Gua) detection in DNA, we digested isolated DNA with nuclease P1 and analyzed for 8-hydroxydeoxyguanosine 5'-monophosphate (8-OH-dGMP) using a high-performance liquid chromatography system equipped with an electrochemical detector (HPLC-ECD). The amount of 8-OH-Gua in the DNA was expressed as the ratio of 8-OH-dGMP to deoxycytidine monophosphate (dCMP). Using this analysis, the background level of 8-OH-Gua in DNA from human lung carcinoma cells (A549) was several-fold lower than that obtained by a previous method. A549 cells were exposed to 20-60 Gy of gamma-radiation and an increase in 8-OH-Gua concentration was observed with increasing gamma-ray dose (0.3 residues per 10(7) dCMP per Gy). Moreover, by an immunohistochemical procedure using a commercial FITC-kit, 8-OH-Gua was clearly detected in A549 cells and the fluorescence intensity of cells with oxidative DNA damage increased with the doses of gamma-irradiation. Using an endonuclease nicking assay, we also found that gamma-rays decreased 8-OH-Gua repair activity. The results indicate that 8-OH-dGMP is a useful and sensitive marker for estimating oxidative damage in DNA.     

Low uptake of [H]2-deoxy-d-glucose by cultured rat Schwann cells

[³H]2-Deoxy-d-glucose (2-DG) was used to investigate the glucose uptake in cultured rat Schwann cells from postnatal Sprague-Dawley rat sciatic nerves. The glucose uptake of Schwann cells slightly increased in a time- and dose-dependent manner. However, the maximal uptake level was much lower than that of ethylnitrosourea (ENU)-induced transformed rat schwannoma-like cells and fibroblasts. By autoradiography of the cultured system, we were able to visualize the accumulation of [³H]2-DG grains in the schwannoma-like cells and fibroblasts, but not in Schwann cells.     

Protective effect of recombinant neutrophil elastase inhibitor (R-020) on sepsis-induced organ injury in rat

Severe inflammatory responses after major surgeries, trauma, and infection develop multiple organ dysfunction. In the mechanisms of the pathogenesis of these responses, activated neutrophils are thought to be important in terms of their ability to produce various kinds of proteinases, which can degrade various proteins constructing human tissues. Among their proteinases, neutrophil elastase is the strongest serine proteinase secreted from activated neutrophils. Thus, we examined in this study the inhibitory effect and therapeutic efficacy of newly produced recombinant human Kunitz-type proteinase inhibitor (R-020), which coded the second domain of human urinary trypsin inhibitor. R-020 was effective in significantly improving the survival rate after induction of the rat lethal peritonitis model (cecal ligation and punctureinduced septic shock model). We suggest that various serine proteinases are implicated in the pathogenesis of neutrophil-related multiple organ failure and that recombinant human Kunitz-type proteinase inhibitor might be effective in the treatment of these kinds of organ dysfunction.     

Clinical significance of measurement of resting energy expenditure in childhood

1. Biliary atresia (BA), as a common disease in Japan, and cystic fibrosis (CF), as an extremely uncommon disease in Japan, were selected to assess the clinical significance of measurement of energy expenditure (EE). 2. Energy expenditure was significantly higher in children with BA than in normal children. 3. Measurement of EE in BA lead to clues to resolving its mechanism by novel assessment of interleukin-6 and leptin. 4. Energy expenditure in children with CF is also higher, but this has been addressed by nutritional intervention with additional calories. 5. Individualization of EE measurement is necessary in the analysis of pathological mechanisms and nutritional management of patients with both common and uncommon diseases.     

Estimation of quantal parameters at the calyx of Held synapse

The calyx of Held has recently emerged as a convenient model system to study CNS synapses. In order to understand the mechanisms of synaptic transmission and short-term synaptic plasticity, quantal parameters and their changes should be estimated precisely. For this purpose, various methods have been applied to the calyx of Held synapse. The results confirm many aspects of the early findings on transmission at the neuromuscular junction. On the other hand, the simplest quantal hypothesis does not work at the calyx of Held, because of additional factors such as heterogeneous release probability of synaptic vesicles, intra- and intersite quantal variability, an overlap of facilitation and depression of transmitter release, changes in quantal sizes due to desensitization and saturation of postsynaptic receptors, and delayed clearance of transmitter from the synaptic cleft. These factors should always be taken into account for fully understanding the mechanisms of synaptic transmission and plasticity.     

Emergence of a unique O3:K6 clone of Vibrio parahaemolyticus in Calcutta, India, and isolation of strains from the same clonal group from Southeast Asian travelers arriving in Japan.

Active surveillance of Vibrio parahaemolyticus infection among hospitalized patients in Calcutta, India, was initiated in January 1994. The incidence of cases of V. parahaemolyticus infection suddenly increased in February 1996 and has remained high since then. One hundred thirty-four strains of V. parahaemolyticus isolated from January 1994 to August 1996 were examined for serovar, the presence of the thermostable direct hemolysin gene (tdh) and tdh-related hemolysin genes (trh1 and trh2), production of urease, and antibiogram. Strains of the O3:K6 serovar appeared for the first time in February 1996. The O3:K6 serovar strains accounted for 50 to 80% of the strains isolated during the high-incidence period (February to August 1996). All of the serovar O3:K6 strains carried the tdh gene but not the trh genes and did not produce urease. All of the isolates except two were sensitive to all of the antibiotics tested. These and the results of analysis by an arbitrarily primed PCR method indicated that the O3:K6 serovar strains belong to a unique clone. When the O3:K6 serovar strains, isolated from travelers arriving in Japan from Southeast Asian countries, were compared by the arbitrarily primed PCR method, the strains isolated between 1982 and 1993 were distinct from Calcutta O3:K6 while the strains isolated in 1995 and 1996 were indistinguishable from the Calcutta O3:K6 strains. The results suggest that this unique O3:K6 clone may have become prevalent not only in Calcutta but also in Southeast Asian countries very recently. Not only the O3:K6 strains but also the non-O3:K6, tdh-bearing strains isolated in 1996 produced thermostable direct hemolysin at high levels, and thus the level of hemolysin produced does not appear to have influenced the high incidence of serovar O3:K6 strains.