Clinico-radiological features of subarachnoid hyperintensity on diffusion-weighted images in patients with meningitis.

AIM: To investigate the clinical and radiological features of meningitis with subarachnoid diffusion-weighted imaging (DWI) hyperintensity. MATERIALS AND METHODS: The clinical features, laboratory data, and radiological findings, including the number and distribution of subarachnoid DWI hyperintense lesions and other radiological abnormalities, of 18 patients seen at five institutions were evaluated. RESULTS: The patients consisted of eight males and 10 females, whose ages ranged from 4 months to 82 years (median 65 years). Causative organisms were bacteria in 15 patients, including Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pneumoniae, and Listeria monocytogenes. The remaining three were fungal meningitis caused by Cryptococcus neoformans. Subarachnoid DWI hyperintense lesions were multiple in 16 of the 18 cases (89%) and predominantly distributed around the frontal lobe in 16 of the 18 cases (89%). In addition to subarachnoid abnormality, subdural empyema, cerebral infarction, and intraventricular empyema were found in 50, 39, and 39%, respectively. Compared with paediatric patients, adult patients with bacterial meningitis tended to have poor prognoses (7/10 versus 1/5; p = 0.1). CONCLUSION: Both bacterial and fungal meningitis could cause subarachnoid hyperintensity on DWI, predominantly around the frontal lobe. This finding is often associated with poor prognosis in adult bacterial meningitis.

Phase II study: treatment of non-Hodgkin's lymphoma with an oral antitumor derivative of bis(2,6-dioxopiperazine).

BACKGROUND: Although razoxane (ICRF-159), a derivative of bis(2,6-dioxopiperazine), has shown significant antitumor activity in several murine tumors, inadequate bioavailability has limited its clinical efficacy. Sobuzoxane (MST-16), another derivative of bis(2,6-dioxopiperazine), has shown activity against a broad spectrum of murine tumors and human tumor xenografts in nude mice and a lack of cross-resistance to vincristine, doxorubicin, cyclophosphamide, fluorouracil, etoposide, and mitomycin C. These findings suggest that MST-16 has a mode of cytocidal activity different from that of other antitumor agents. PURPOSE: The present late phase II study was conducted to evaluate the clinical efficacy and toxicity of MST-16 in non-Hodgkin's lymphoma (NHL). METHODS: As part of a multi-institutional cooperative study, we conducted a study of MST-16 in 27 patients with NHL who were assessable for drug efficacy and toxicity. MST-16, a bis(2,6-dioxopiperazine) analogue and an inhibitor of topoisomerase II, was administered orally at a dose of 1600 mg/m2 a day for 5-7 days at intervals of 2-3 weeks. RESULTS: Response consisted of one complete remission and seven partial remissions in 27 assessable patients. Response was achieved at a median of 13 days (range, 9-62 days) after initiation of therapy and lasted a median of 46 days (range, 29-155 days). Major toxic effects were leukopenia in 70% of the patients, thrombocytopenia in 44%, and gastrointestinal disorders in 37%. CONCLUSIONS: MST-16 was shown to be effective in NHL and deserves further clinical trial, since the drug shows little cross-resistance to available antitumor drugs. IMPLICATIONS: Phase II clinical studies of MST-16 in treatment of breast cancer, gastric cancer, and adult T-cell leukemia and lymphoma are also being conducted in Japan. Future trials of combination chemotherapy using MST-16 with other antitumor drugs are warranted in view of the additive effects observed in studies of MOLT-3 cells and studies of L1210 leukemia in mice.

Vascular endothelial growth factor inhibits apoptotic death in hematopoietic cells after exposure to chemotherapeutic drugs by inducing MCL1 acting as an antiapoptotic factor.

We reported previously that vascular endothelial growth factor (VEGF) inhibits the apoptotic death of hematopoietic cells that is induced by exposure to ionizing radiation (O. Katoh et al., Cancer Res., 55: 5687-5692, 1995). In this study, we show that VEGF also inhibits apoptotic cell death that is induced by exposure to the chemotherapeutic drugs etoposide and doxorubicin. To elucidate the molecular mechanisms underlying this inhibitory effect of VEGF, we examined expression levels of BCL2 family proteins in CMK86, a human leukemia cell line, after treatment with VEGF. Northern blotting and immunoblotting analyses revealed that the expression level of MCL1, a member of the BCL2 family, was increased by VEGF. Moreover, to examine the effects of MCL1 on apoptotic cell death induced by exposure to etoposide, we generated a clonal U937 myeloid leukemia cell line transfected with vectors that promoted the constitutive expression of MCL1. MCL1 decreased the caspase 3 activity induced by exposure to etoposide and increased the viability of the transfected cells after etoposide exposure. Therefore, MCL1 may be involved in the inhibitory effect of VEGF on apoptotic cell death.

Radiation safety design for the J-PARC Project.

The High-Intensity Proton Accelerator Project, named J-PARC, is in progress, with the aim of enabling studies on the latest basic science and the advancement of nuclear technology. In the project, a high-energy proton accelerator complex with the world's highest instantaneous intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.

The Krüppel-type zinc finger family gene, HKR1, is induced in lung cancer by exposure to platinum drugs.

To investigate the molecular mechanism associated with the signaling pathway of platinum drug administration, we focused on the C2H2-type zinc finger (ZNF) transcription factor gene family. Here we show cloning of a Krüppel-type ZNF gene, HKR1, which contains Krüppel-associated box (KRAB) domain and ZNF motifs. We found that mRNA expression of the HKR1 gene was induced in lung-cancer cell lines by exposure to cisplatin using Northern blot analysis. Moreover, we also found that HKR1 mRNA expression levels in lung cancers were higher than those in normal lung tissues, and that high expression levels in lung cancers were associated with antemortem platinum drug administration. These results suggest that HKR1 may be associated with the regulation of a signaling pathway involved in the progression of lung cancer or the acquisition of resistance to platinum drugs.

Glutathione S-transferase-pi gene expression and platinum drug exposure in human lung cancer.

We examined the association between the gene expression levels of glutathione S-transferase-pi (GST-pi) and platinum drug exposure in human lung cancer. First we monitored GST-pi gene expression levels in two lung cancer cell lines and in peripheral mononuclear cells of ten previously untreated lung cancer patients after platinum drug exposure. Next we examined GST-pi gene expression levels in 40 lung cancer autopsy specimens. The GST-pi gene expression levels were assessed by the quantitative reverse transcription-polymerase chain reaction or Northern blot analysis. The GST-pi gene expression was not induced by platinum drugs either in vitro and in vivo within 24 h of exposure. In contrast, GST-pi gene expression levels in lung cancer tissues of patients who had been exposed to platinum drugs at least 1 month before death were significantly higher than that in those of patients who had not been exposed. These results suggest that GST-pi gene expression is associated with chronic exposure to platinum drugs in lung cancer and/or the stress response to xenobiotics.

Molecular characterization of epidemic multiresistant Staphylococcus haemolyticus isolates.

Fifty-five Staphylococcus haemolyticus specimens isolated from patients and neonatal intensive care unit staff were tested for susceptibility to 12 antimicrobial agents. There were 34 multidrug-resistant isolates which were resistant to oxacillin, ampicillin, cefazolin, cefmetazole, imipenem, and gentamicin. These isolates had a higher frequency of resistance to tobramicin and ofloxacin, and relatively high MICs (2 to 4 micrograms/mL) for vancomycin, although none of the isolates were vancomycin resistant. To investigate hospital-acquired colonization and infection by multiresistant S. haemolyticus, we examined all isolates by pulsed-field gel electrophoresis (PFGE) after SmaI and SstII digestion, and detected an endemic PFGE pattern in multiresistant isolates. The results suggested that local spread of multiresistant S. haemolyticus was hospital acquired, and that the hospital staffs functioned as a reservoir.

Cloning and restriction analysis of DNA conferring new quinolone antimicrobial agent resistance from Staphylococcus aureus and other coagulase-negative Staphylococcus species.

DNA conferring resistance to new quinolone antimicrobial agents (NQR) in clinical isolates of Staphylococcus aureus and coagulase-negative staphylococci (CNS), S. epidermidis and S. haemolyticus, was analyzed after cloning in Escherichia coli. The NQR phenotypes were expressed in E. coli at lower levels. NQR gene(s)-carring HindIII fragments were very similar to each other among S. aureus or CNS, although the S. aureus fragments differed from the CNS fragments in terms of the NQR phenotypes and restriction endonuclease maps. The data suggest the possibility that the NQR genes have disseminated in evolutionarily distinct routes among S. aureus and CNS.

Induction of cytochrome P450 3A4 by docetaxel in peripheral mononuclear cells and its expression in lung cancer.

Several recent studies have demonstrated that the cytochrome p450 (CYP) family plays an important role in the metabolism of taxanes. However, the role of CYP gene expression in tumors and peripheral mononuclear cells (PMN) is unknown. We therefore investigated the levels of CYP3A4 and CYP2C gene expression using reverse transcription polymerase chain reaction (RT-PCR) in PMN from 16 previously untreated lung cancer patients to determine whether the expression of the two genes is induced by docetaxel (TXT). Neither the CYP3A4 nor the CYP2C gene was induced after administration of carboplatin (CBDCA) alone. Expression of the CYP3A4 gene was induced by the administration of TXT alone or TXT and CBDCA, but expression of the CYP2C gene was unaffected. We also measured the expression of both genes using RT-PCR in 20 autopsy samples (ten non-small-cell lung cancers and their corresponding normal lung tissues) obtained from patients who had not received any chemotherapy during life. The level of CYP2C gene expression in samples of lung cancer was significantly higher than in normal lung tissue, but the level of CYP3A4 gene expression was not. These results suggest that the CYP3A4 gene is induced by TXT, and that it plays an important role in intracellular TXT metabolism.

Effects of azoxymethane on X-ray induced intestinal metaplasia in Donryu rats.

The present study was undertaken to determine the effect of azoxymethane (AOM) administration on intestinal metaplasia induced by X-irradiation in male Donryu rats. Five-week-old animals were X-irradiated with two doses of 10 Gy each at a 3-day interval or three X-ray doses of 10 Gy at a 2-day interval and then received AOM injections i.m. at a dose of 15 mg/kg body weight once weekly for 3 weeks, 6 months after irradiation. Alkaline phosphatase positive foci were decreased after AOM treatments, but aberrant crypt like-foci appeared within areas of intestinal metaplasia. In contrast no induction was observed in normal-appearing gastric mucosa.

Effect of methylmercury (CH3HgCl) injury on nitric oxide synthase (NOS) activity in cultured human umbilical vascular endothelial cells.

The effects of methylmercury (CH3HgCl; MeHg) on the production of nitric oxide (NO) and the activity of the enzyme, nitric oxide synthase (NOS), in cultured human umbilical vascular endothelial cells (HUVEC) were examined. To assess the production of NO by HUVEC, platelet aggregation experiments were performed using cuvettes lined with HUVEC. Thrombin (0.05 U/ml)-induced platelet aggregation was inhibited in HUVEC pretreated with indomethacin (1 microM), an inhibitor of the cyclo-oxygenase pathway. The anti-platelet aggregatory effect of HUVEC treated with indomethacin was decreased dose-dependently by 48-h pretreatment with MeHg (0.5-2 microM). The effect of MeHg on the NADPH diaphorase staining of NOS in HUVEC showed dose-dependent cytotoxicity in regard to NOS activity. These findings suggest that MeHg inhibits the production of NO by HUVEC, an action which may be dependent on the cytotoxic effect exerted by MeHg on NOS activity.

Expression of lung-resistance protein gene is not associated with platinum drug exposure in lung cancer.

BACKGROUND: Platinum drug resistance is an important problem in lung cancer chemotherapy. In this study, we examined lung-resistance protein (LRP) gene expression in vivo and in vitro in relation to platinum drug exposure. MATERIALS AND METHODS: The expression levels of the LRP gene were assessed by the reverse transcription polymerase chain reaction, in 80 autopsy samples (40 lung tumors and 40 corresponding normal lung tissues), two lung cancer cell lines and in peripheral mononuclear cells collected from 8 lung cancer patients before and after platinum drug administration. RESULTS: The LRP gene expression levels of autopsy specimens exposed antemortem to platinum drugs were not significantly different to those of specimens without platinum drug exposure, for both lung tumors and normal lung tissues. Our results also demonstrate that LRP gene expression was not induced by platinum drugs either in vitro or in vivo. CONCLUSIONS: The present results indicate that LRP gene expression is not associated with platinum drug exposure in lung cancer.

Carboplatin AUC and gamma-glutamylcysteine synthetase gene expression in peripheral mononuclear cells of lung cancer patients.

BACKGROUND: To investigate the association between glutathione-related enzymes and carboplatin (CBDCA) dose, we examined gene expression levels for both subunits of gamma-glutamylcysteine synthetase (heavy; gamma-GCSh, light; gamma-GCS1) in peripheral mononuclear cells (PMN) of lung cancer patients before and after CBDCA administration. MATERIALS AND METHODS: PMN and plasma samples were obtained from 10 advanced non-small lung cancer patients before and after CBDCA administration. We analyzed the gene expression levels by reverse transcription-polymerase chain reaction. RESULTS: Gamma-GCSh expression levels in PMN increased within 24 hours after CBDCA administration, whereas gamma-GCS1 expression levels did not. However, the actual area under the concentration curve (AUC) of CBDCA did not correlate with gamma-GCSh expression at 24 hours or the increased ratio of gamma-GCSh expression in PMN. CONCLUSION: Expression of gamma-GCSh is induced by CBDCA, however, CBDCA AUC is not a determinant for the increased expression levels of gamma-GCSh in PMN.

Microorganisms isolated from infected aural fistulas.

Aural fistula is a congenital deformity of the external ear relatively common in Orientals and rare in Caucasians. Suppuration tends to occur, and chemotherapy rather than surgical drainage should be attempted. However, the lack of information concerning infected aural fistulas has made appropriate chemotherapy difficult. Microorganisms isolated from 13 cases of infected aural fistulas were studied from January 1981 to December 1982. Six species and 22 strains were isolated; nonsporeforming faculative anaerobes were detected in 12 cases. The isolated pathogens included Peptococcus sp (10 cases), Peptostreptococcus sp (3), Bacteroides sp (3), and Fusobacterium sp (2). One case exhibited only Staphylococcus aureus. Our data also stresses the etiologic importance of anaerobic gram-positive cocci in infected aural fistulas.

Effect of cadmium injury on growth and migration of cultured human vascular endothelial cells.

The effect of cadmium chloride (CdCl2) on the cell proliferation and migration of cultured human umbilical vein endothelial cells (HUVECs) was quantitatively analyzed. The HUVEC viable cell count decreased dose-dependently after exposure to Cd (cadmium chloride, 10 nM-1 mM). Morphologic examination by phase-contrast microscopy revealed severe damaging effects of Cd at higher concentrations. The cytotoxic effect of Cd (10 microM-1 mM) on DNA synthesis was also concentration-dependent. When the distance endothelial cells grew out from the scraped edge of a monolayer was measured, HUVEC outgrowth was found to be inhibited by Cd (1.0 microM-1.0 mM) in a dose-dependent manner. These findings suggest that HUVEC cell proliferation and migration are susceptible to Cd cytotoxicity, and that this may be involved in the pathogenesis of atherosclerosis.

Copper enhances EDNO (endothelium-derived nitric oxide) activity by cultured human vascular endothelial cells.

The effect of copper sulfate (Cu) on viable cell number, endothelium-derived nitric oxide (EDNO), and nitric oxide synthase (NOS) in cultured human umbilical vascular endothelial cells (HUVEC) was investigated. The viable cell number was not affected by the addition of Cu (1.0-500.0 microM). To assess the effect of EDNO by HUVEC, platelet aggregation experiments were performed, using cuvettes lined with HUVEC. Thrombin (0.05 units/ml)-induced platelet aggregation was markedly inhibited in the presence of HUVEC compared with aggregation in the absence of HUVEC. The HUVEC-dependent anti-platelet aggregatory effect was slightly reduced when HUVEC were pretreated with indomethacin (IND; 1.0 micro M), an inhibitor of the cyclo-oxygenase pathway. However, the thrombin-induced platelet aggregation in the presence of HUVEC pretreated with IND was smaller than that in the absence of HUVEC, which is dependent on EDNO. The anti-platelet aggregatory effect of HUVEC pretreated with IND was increased dose-dependently by 48-hour pretreatment of HUVEC with Cu (1.0-100.0 microM). To assess the effect of Cu on NOS, HUVEC were stained with NOS/NADPH diaphorase. However, there were no significant differences in the NOS-positive HUVEC cell count between cells without Cu and those with various concentrations of Cu. These findings suggest that Cu stimulates the activity of EDNO, which action may be dependent on Cu decreasing EDNO-oxidative damage.

Methylmercury modulation of monocyte chemotactic protein-1 mRNA expression in human peripheral blood mononuclear cells.

The effect of methylmercury (MeHg; CH3HgCl) on the gene expression of monocyte chemotactic protein-1 (MCP-1) by human peripheral blood mononuclear cells (PBMC) was examined. PBMC were exposed with or without thrombin (1 U/ml) or MeHg (0.3 or 3.0 microM) for 24 hours. The total RNA was reverse transcribed and then amplified by the method of reverse transcriptase-polymerase chain reaction (RT-PCR). Thrombin enhanced MCP-1 mRNA expression in PBMC. MeHg inhibited thrombin-stimulated MCP-1 mRNA expression in a dose dependent manner. These findings suggest that MeHg affects the atherosclerotic process by changing MCP-1 mRNA expression in PBMC.

Assessment of production of endothelium-derived relaxing factor by cultured porcine cerebral microvessel endothelial cells.

To establish an experimental system to assess the production of endothelium-derived relaxing factor (EDRF) by cultured porcine cerebral microvessel endothelial cells (PCMEC), the effect of PCMEC on thrombin-induced platelet aggregation was studied. For the platelet aggregation cuvettes lined with PCMEC were used. The cuvettes were prepared by seeding PCMEC in gelatin-coated cuvettes at a cell density of 2 x 10(5) cells/ml and culturing for 48 hours. Thrombin-induced platelet aggregation was markedly inhibited in the presence of PCMEC. Indomethacin reduced the PCMEC-dependent anti-platelet aggregatory effect. This PCMEC-dependent anti-platelet aggregatory effect was increased by the addition of bradykinin which stimulates the production of EDRF. These findings suggest that this simple experimental system is useful in assessing the production of EDRF by PCMEC and in examining the effects of various chemicals (or agents) on EDRF production.