Morphological change in the MNNG-treated rat gastric mucosa

To investigate the process of carcinogenesis in gastric cancer, we studied the histological features of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treated rats. Samples of the gastric mucosa from both MNNG-treated and control rats were histologically examined every 2 months, for 10 months. In 40% of the MNNG-treated rats, atrophy in the gastric mucosa was observed after 2 months, and regenerative epithelium was observed after 4 months, followed by adenomatous proliferation and disappearance of the tight junction electron microscopically after 6 months. A small intestinal cancer had developed in 2 rats at 6 months. While gastric cancer had developed in 3 rats at 8 months, and in one of these 3 rats, peritoneal dissemination was observed macroscopically and histologically. These results suggested that adenomatous proliferation and disappearance of the tight junction observed electron microscopically were characteristic pathological features of precancerous lesions in the stomach in MNNG-treated rat.

Histopathological study of venous aneurysms in patients with dural arteriovenous fistulas

OBJECT

Of all intracranial dural arteriovenous fistulas (DAVFs), those with cortical venous drainage associated with cortical venous ectasia or varices are predisposed to an aggressive course and produce progressive neurological symptoms or hemorrhages. The authors undertook a histological examination of venous aneurysms and arterialized veins in the proximity of these aneurysms that had been surgically removed in patients with DAVFs.

METHODS

Surgical specimens were obtained in eight patients. The excised venous aneurysms and the arterialized veins in their proximity were stained using hematoxylin and eosin, van Gieson's elastic, and Masson's trichrome stain. Immunostaining was also performed for alpha smooth-muscle actin, desmin, and factor VIII antigen. Five of the patients had presented with venous hypertension, and three had intracranial hemorrhages. The arterialized vein obtained in the proximity of the venous aneurysm exhibited local irregular intimal thickening; the internal elastic lamina (IEL) was grossly preserved. All venous aneurysms in patients with venous hypertension manifested medial thickening and local intimal thickening with loss of IEL; the thickness of the wall was relatively uniform. In contrast, the wall thickness of venous aneurysms in patients with hemorrhage was extremely irregular and there was no clear delineation between the media and the intima. In media with complete disappearance of IEL, there was scant muscle tissue.

CONCLUSIONS

Degenerative changes in venous aneurysms in patients with hemorrhage were much greater than in patients with venous hypertension, possibly because hemorrhages result from a more complicated interplay of anatomical, hemodynamic, and degenerative factors.

Complete regression of xenografted human carcinomas by camptothecin analogue-carboxymethyl dextran conjugate (T-0128)

Clinically available camptothecins (CPTs), such as irinotecan (CPT-11) and topotecan, represent one of the most promising classes of antitumor agents, despite their toxicity. To improve their pharmacological profiles, a new macromolecular prodrug, denoted T-0128, was synthesized. This prodrug is a novel CPT analogue (T-2513)-carboxymethyl (CM) dextran conjugate via a triglycine spacer, with a molecular weight of Mr 130,000. This study was designed to test the concept that the rational design of a CPT-polymer conjugate would increase the efficacy of the parent drug. The in vivo antitumor study against Walker-256 carcinoma demonstrated that T-0128 was 10 times as active as T-2513, supporting this concept. Additionally, comparative efficacy studies of T-0128, T-2513, CPT-11, and topotecan were performed using a panel of human tumor xenografts in nude mice, showing the advantage of T-0128 over these CPTs. The maximal tolerated doses (MTDs) of T-0128, T-2513, and CPT-11 were comparable. Even a single i.v. injection of T-0128 at 6 mg/kg (based on the amount of T-2513 bound to CM dextran) induced complete regression of MX-1 mammary carcinoma. T-0128 at 10 mg/kg weekly for 3 weeks (one-tenth of its MTD) cured LX-1 lung carcinoma. Also, T-0128 below its MTD consistently cured or regressed St-4 gastric and HT-29 colorectal tumor xenografts that are highly refractory to CPTs. These demonstrate the broad range of therapeutic doses achieved with T-0128. Pharmacokinetic studies were performed to correlate the efficacy results obtained for T-0128 with plasma and tissue drug concentrations using Walker-256 tumor-bearing rats. Results showed that after i.v. administration of T-0128, the conjugate continued to circulate at a high concentration for an extended period, resulting in tumor accumulation. In the tumor, the sustained release of T-2513 occurred. In contrast, T-2513 disappeared rapidly from the body. The significant increases in the amount and exposure time of released T-2513 in the tumor explain well the enhanced efficacy of T-0128. In conclusion, this study indicated that T-0128 improved the potency of T-2513, demonstrating the proof of the above concept.

Structure and activity of specific inhibitors of thymidine phosphorylase to potentiate the function of antitumor 2'-deoxyribonucleosides

A new class of 5-halogenated pyrimidine analogs substituted at the 6-position was evaluated as competitive inhibitors of thymidine phosphorylase (TPase). The most potent member of the series was 5-chloro-6-(2-iminopyrrolidin-1-yl)methyl-2,4(1H,3H)-pyrimidine dio ne hydrochloride (TPI), which has an apparent K(i) value of 1.7 x 10(-8) M. TPI selectively inhibited the activity of TPase, but not that of uridine phosphorylase, thymidine kinase, orotate phosphoribosyltransferase, or dihydropyrimidine dehydrogenase. In vitro inhibition studies of TPI using a thymidine analogue, 5-trifluoromethyl-2'-deoxyuridine (F(3)dThd), as the substrate demonstrated that F(3)dThd phosphorolytic activity was inhibited markedly by TPI (1 x 10(-6) M) in extracts from the liver, small intestine, and tumors of humans, from the liver and small intestine of cynomolgus monkeys, and from the liver of rodents, but not from the liver or small intestine of dogs or the small intestine of rodents, suggesting that the distribution of TPase differs between humans and animal species, and that TPI could contribute to the modulation of TPase in humans. When F(3)dThd or 5-iodo-2'-deoxyuridine (IdUrd) was coadministered to mice with TPI at a molar ratio of 1:1, the blood levels of F(3)dThd (or IdUrd) were about 2-fold higher than when F(3)dThd (or IdUrd) was administered alone. In monkeys, the maximum concentration (C(max)) and the area under the concentration-time curve (AUC) after oral F(3)dThd alone were 0.23 microg/mL and 0.28 microg. hr/mL, respectively, but markedly increased to 15.18 microg/mL (approximately 70-fold) and 28.47 microg. hr/mL (approximately 100-fold), respectively, when combined with equimolar TPI. Combined oral administration of TPI significantly potentiated the antitumor activity of F(3)dThd on AZ-521 human stomach cancer xenografts in nude mice. In conclusion, TPI may contribute not only to inhibition of TPase-mediated biological functions but also to potentiation of the biological activity of various 2'-deoxyuridine and thymidine derivatives by combining with them.

[Causative agents for lung carcinogenesis]

Lung cancer is a leading cause of malignancy-related death in Japan, and its incidence is still rising steeply. Various factors, including cigarette smoking, asbestos, and diet, have been reported to correlate with the development of lung cancer. Of these factors, cigarette smoking is believed as the major carcinogen for lung cancer. Recent studies indicate that cigarette smoke carcinogens cause genetic damages at both oncogenes(K-ras) and tumor suppressor genes(p53) of lung cancer, and hence initiate and promote the development of lung cancer. This article reviews recent advances in the molecular mechanisms of lung cancer carcinogenesis.

[Erdheim-Chester disease presenting with pulmonary lesion]

A 49-year-old man first visited our hospital in 1991 for further examination of abnormal pulmonary shadows. A chest radiograph and computed tomographic (CT) scan showed diffuse reticular shadows in both lung fields. The findings from a transbronchial lung biopsy specimen were not conclusive. Although there was little change in the abnormal pulmonary shadows, the patient's lung functions gradually deteriorated, indicating an obstructive defect. The patient was admitted in 1998 with the chief complaint of increasing dyspnea on exertion. A thoracoscopic lung biopsy specimen revealed proliferation of histiocytes with fibrosis in the pleura and perivascular interstitium. Immunohistochemically, the histiocytic cells were CD68-positive, alpha 1-antichymotripsin-positive, S100 protein-negative, and CD1a-negative. A bone scintigram and magnetic resonance images showed symmetrical diametaphyseal bone lesions in the distal femurs and the proximal tibiae; however, the epiphyses were spared. These findings were consistent with Erdheim-Chester disease. This is the first reported case of Erdheim-Chester disease with pulmonary involvement in Japan.

Four cases of anti-myeloperoxidase antibody-related rapidly progressive glomerulonephritis during the course of idiopathic pulmonary fibrosis

We report here 4 cases of rapidly progressive glomerulonephritis (RPGN) which developed during the management of idiopathic pulmonary fibrosis. In each patient, pulmonary disease preceded the onset of nephritis by 1 to 6 years. All patients had a high titer of serum autoantibodies against myeloperoxidase (MPO-ANCA) when the diagnosis of RPGN was made. Although the association of pulmonary fibrosis with ANCA-related glomerulonephritis has been occasionally described in the past literature, the sequence of pulmonary and renal injury has not been well defined. The present report demonstrates that idiopathic pulmonary fibrosis exists as a preceding condition in some patients with MPO-ANCA-related nephritis.

Interleukin 8 expression regulates tumorigenicity and metastases in androgen-independent prostate cancer

Interleukin 8 (IL-8) is mitogenic and chemotactic for endothelial cells. Within a neoplasm, IL-8 is secreted by inflammatory and neoplastic cells. The highly metastatic PC-3M-LN4 cell line overexpresses IL-8 relative to the poorly metastatic PC-3P cell line. We evaluated whether IL-8 expression by human prostate cancer growing within the prostate of athymic nude mice regulates tumor angiogenesis, growth, and metastasis. PC-3P cells were transfected with the full-length sense IL-8 cDNA, whereas PC-3M-LN4 cells were transfected with the full-sequence antisense IL-8 cDNA. Control cells were transfected with the neomycin resistance gene (Neo). In vitro, sense-transfected PC-3P cells overexpressed IL-8-specific mRNA and protein, which resulted in up-regulation of matrix metalloproteinase 9 (MMP-9) mRNA, and collagenase activity, resulting in increased invasion through Matrigel. After antisense transfection of the PC-3M-LN4 cells, IL-8 and MMP-9 expression, collagenase activity, and invasion were markedly reduced relative to controls. After orthotopic implantation, the sense-transfected PC-3P cells were highly tumorigenic and metastatic, with significantly increased neovascularity and IL-8 expression compared with either PC-3P cells or controls. Antisense transfection significantly reduced the expression of IL-8 and MMP-9 and tumor-induced neovascularity, resulting in inhibition of tumorigenicity and metastasis. These results demonstrate that IL-8 expression regulates angiogenesis in prostate cancer, in part by induction of MMP-9 expression, and subsequently regulates the growth and metastasis of human prostate cancer.

Effect of the linking position of a side chain in bis(quinolylmethyl)ethylenediamine as a DNA binding agent

Two bisquinoline derivatives, N,N'-bis(2-quinolylmethyl)ethylenediamine (2-BQME) and N,N'-bis(8-quinolylmethyl)ethylenediamine (8-BQME) have been synthesized, and their ability to bind to duplex DNA was studied. 8-BQME bound to DNA more strongly than 2-BQME, judging from the extent of increase in the melting temperature of duplex DNA, the UV-vis spectral change, and ethidium displacement assay. These compounds exhibited apparent AT-specificity suggesting minor groove binding in addition to intercalation.

Induction of chemokine secretion and enhancement of contact-dependent macrophage cytotoxicity by engineered expression of granulocyte-macrophage colony-stimulating factor in human colon cancer cells

We investigated the role of tumor cell-derived GM-CSF in recruitment and tumoricidal activation of tissue macrophages. Transfection of the murine GM-CSF gene into KM12SM human colon cancer cells decreased the tumorigenicity of transfected cells and nontransfected bystander colon cancer cells in nude mice. Sequential tissue sections from sites injected with high GM-CSF-producing tumor cells (but not from nontransfected or low GM-CSF-producing cells) demonstrated a dense infiltration of polymorphonuclear cells (PMN), followed by infiltration of macrophages, which correlated with expression of the macrophage-inflammatory protein-1alpha and the monocyte chemoattractant protein-1 (MCP-1) in mouse PMN and macrophages. GM-CSF-producing KM12SM cells were highly sensitive to lysis by mouse macrophages and also increased macrophage-mediated lysis of bystander nontransfected KM12SM cells. The incubation of macrophages with GM-CSF induced expression of the CD11b surface adhesion molecule, which was associated with increased attachment to tumor cells. All KM12SM cells were sensitive to macrophage-mediated lysis in the presence of rGM-CSF and recombinant MCP-1. Collectively, the results demonstrate that tumor cell-derived GM-CSF stimulates PMN and macrophages to secrete macrophage-inflammatory protein-1alpha and MCP-1, which triggers recruitment of mononuclear cells, induces expression of adhesion molecules on macrophages, and enhances contact-dependent cytolysis of tumor cells.

Cloning and over-expression of thermostable Bacillus sp. YM55-1 aspartase and site-directed mutagenesis for probing a catalytic residue

A thermostable aspartase gene (aspB) from Bacillus sp. YM55-1 was cloned and the gene sequenced. The aspB gene (1407 bp ORF) encodes a protein with a molecular mass of 51 627 Da, consisting of 468 amino-acid residues. An amino-acid sequence comparison revealed that Bacillus YM55-1 aspartase shared 71% homology with Bacillus subtilis aspartase and 49% with Escherichia coli and Pseudomonas fluorescens aspartases. The E. coli TK237/pUCASPB strain, which was obtained by transforming E. coli TK237 (aspartase-null strain) with a vector plasmid (pUCASPB) containing the cloned aspB gene, produced a large amount of the enzyme corresponding to > 10% of the total soluble protein. The over-expressed recombinant enzyme (native molecular mass: 200 kDa) was purified effectively and rapidly using heat treatment and affinity chromatography. In order to probe the catalytic residues of this enzyme, two conserved amino-acid residues, Lys183 and His134, were individually mutated to alanine. Although the tertiary structure of each mutant was estimated to be the same as that of wild-type aspartase in CD and fluorescence measurements, the Lys183Ala mutant lost its activity completely, whereas His134Ala retained full activity. This finding suggests that Lys183 may be involved in the catalytic activity of this thermostable Bacillus YM55-1 aspartase.

Differential expression of E-cadherin and type IV collagenase genes predicts outcome in patients with stage I non-small cell lung carcinoma

Because routine histopathological examination of primary non-small cell lung cancer does not predict disease outcome, we correlated disease outcome with the expression level of multiple genes that regulate distinct steps of the metastatic process in 60 formalin-fixed, paraffin-embedded, archival specimens of stage I lung carcinoma from patients undergoing curative surgery at the M. D. Anderson Cancer Center. The expression of E-cadherin (related to cell cohesion), type IV collagenase [matrix metalloproteinase (MMP)-2 and MMP-9, related to invasion], and three angiogenic molecules, basic fibroblast growth factor, vascular endothelial growth factor/vascular permeability factor, and interleukin 8, were examined by a colorimetric in situ mRNA hybridization technique. The expression levels of the individual genes analyzed by a Cox univariate analysis were not prognostic. In contrast, the ratio between expression of type IV collagenases (mean of the expression of MMP-2 and MMP-9) and E-cadherin, the MMP:E-cadherin ratio (measured at the periphery of each tumor), was significantly higher in patients with recurrent disease than in patients who remained disease free (P = 0.00003). Longer overall survival and reduced disease recurrence rates were significantly associated with a lower MMP:E-cadherin ratio (<2) by a Kaplan-Meier survival analysis (P = 0.0002 and P = 0.0001, respectively). Multiple covariate analyses of overall and disease-free survival also concluded that the MMP:E-cadherin ratio was a significant prognostic factor when corrected for age (P = 0.0001). Determination of this gene expression ratio in individual human lung cancers might therefore be used to direct tailored treatment for individual patients with resectable lung cancer.

Treatment for malignant pleural effusion of human lung adenocarcinoma by inhibition of vascular endothelial growth factor receptor tyrosine kinase phosphorylation

Malignant pleural effusion (PE) is associated with advanced human lung cancer. We found recently, using a nude mouse model, that vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) is responsible for PE induced by non-small cell human lung carcinoma cells. The purpose of this study was to determine the therapeutic potential of a VEGF/VPF receptor tyrosine kinase phosphorylation inhibitor, PTK 787, against PE formed by human lung adenocarcinoma (PC14PE6) cells. PTK 787 did not affect the in vitro proliferation of PC14PE6 cells, whereas it specifically inhibited proliferation of human dermal microvascular endothelial cells stimulated by VEGF/VPF. A specific platelet-derived growth factor receptor tyrosine kinase inhibitor, CGP57148 (used as a control because PTK 787 also inhibits platelet-derived growth factor receptor tyrosine kinases), had no effect on proliferation of PC14PE6 or human dermal microvascular endothelial cells. i.v. injection of PC14PE6 cells into nude mice produced lung lesions and a large volume of PE containing a high level of VEGF/VPF. Oral treatment with CGP57148 had no effect on PE or lung metastasis. In contrast, oral treatment with PTK 787 significantly reduced the formation of PE but not the number of lung lesions. Furthermore, treatment with PTK 787 significantly suppressed vascular hyperpermeability of PE-bearing mice but did not affect the VEGF/VPF level in PE or expression of VEGF/VPF protein and mRNA in the lung tumors of PC14PE6 cells in vivo. These findings indicate that PTK 787 reduced PE formation mainly by inhibiting vascular permeability, suggesting that this VEGF/VPF receptor tyrosine kinase inhibitor could be useful for the control of malignant PE.

Novel Mn(II)Mn(III)Mn(II) trinuclear complexes with carbohydrate bridges derived from seven-coordinate manganese(II) complexes with N-glycoside

Reactions of MnX2.nH2O with tris(N-(D-mannosyl)-2-aminoethyl)amine ((D-Man)3-tren), which was formed from D-mannose and tris(2-aminoethyl)amine (tren) in situ, afforded colorless crystals of [Mn((D-Man)3-tren)]X2 (3a, X = Cl; 3b, X = Br; 3c, X = NO3; 3d, X = 1/2SO4). The similar reaction of MnSO4.5H2O with tris(N-(L-rhamnosyl)-2-aminoethyl)amine ((L-Rha)3-tren) gave [Mn((L-Rha)3-tren)]SO4 (4d), where L-rhamnose is 6-deoxy-L-mannose. The structures of 3b and 4d were determined by X-ray crystallography to have a seven-coordinate Mn(II) center ligated by the N-glycoside ligand, (aldose)3-tren, with a C3 helical structure. Three D-mannosyl residues of 3b are arranged in a delta(ob3) configuration around the metal, leading to formation of a cage-type sugar domain in which a water molecule is trapped. In 4d, three L-rhamnosyl moieties are in a delta(lel3) configuration to form a facially opened sugar domain on which a sulfate anion is capping through hydrogen bonding. These structures demonstrated that a configurational switch around the seven-coordinate manganese(II) center occurs depending on its counteranion. Reactions of 3a, 3b, and 4d with 0.5 equiv of Mn(II) salt in the presence of triethylamine yielded reddish orange crystals formulated as [[Mn((aldose)3-tren)]2Mn(H2O)X3.nH2O (5a, aldose = D-Man, X = Cl; 5b, aldose = D-Man, X = Br; 6d, aldose = L-Rha, X = 1/2SO4). The analogous trinuclear complexes 6a (aldose = L-Rha, X = Cl), 6b (aldose = L-Rha, X = Br), and 6c (aldose = L-Rha, X = NO3) were prepared by the one-pot reaction of Mn(II) salts with (L-Rha)3-tren without isolation of the intermediate Mn(II) complexes. X-ray crystallographic studies revealed that 5a, 5b, 6c, and 6d have a linearly ordered trimanganese core, Mn(II)Mn(III)Mn(II), bridged by two carbohydrate residues with Mn-Mn separations of 3.845(2)-3.919(4) A and Mn-Mn-Mn angles of 170.7(1)-173.81(7) degrees. The terminal Mn(II) atoms are seven-coordinate with a distorted mono-face-capped octahedral geometry ligated by the (aldose)3-tren ligand through three oxygen atoms of C-2 hydroxyl groups, three N-glycosidic nitrogen atoms, and a tertiary amino group. The central Mn(III) atoms are five-coordinate ligated by four oxygen atoms of carbohydrate residues in the (aldose)3-tren ligands and one water molecule, resulting in a square-pyramidal geometry. In the bridging part, a beta-aldopyranosyl unit with a chair conformation bridges the two Mn(II)Mn(III) ions with the C-2 mu-alkoxo group and with the C-1 N-glycosidic amino and the C-3 alkoxo groups coordinating to each metal center. These structures could be very useful information in relation to xylose isomerases which promote aldose-ketose isomerization by using divalent dimetal centers such as Mn2+, Mg2+, and Co2+.

Submucosal gastric cancer with lymph node metastasis--a clinicopathological study

We have reviewed the clinicopathological features of submucosal gastric cancer with lymph node metastasis. The degree of vertical submucosal infiltration was classified into three stages as sm1, sm2 or sm3. The number of cases with lymph node metastasis of sm3 was significantly more than that of sm1 or sm2. We found no correlation between the tumor size and the rate of lymph node metastasis from submucosal invasive cancer. Accordingly, we concluded that the vertical submucosal infiltration was a more important factor for lymph node metastasis than horizontal infiltration. Minimal invasive surgery was recommended for a tumor measuring 1 cm or less in size with vertical submucosal invasion of sm1 or sm2.

Histopathological findings of the lower esophagus after total gastrectomy in rat

It is now accepted that the incidence of esophageal carcinoma is highest in the middle thoracic region. Esophageal carcinoma after gastrectomy, however, has a tendency to develop in the lower region. This study was designed to investigate the role of reflux of gastroduodenal juice in the genesis of carcinoma in the esophagus. We found a possible correlation between the development of esophageal carcinoma and gastrectomy, related to alkaline reflux into the esophagus. To elucidate this correlation, the role of alkaline reflux of duodenal contents in the development of esophageal squamous cell carcinoma was investigated in Wister rats. Gastrectomized rats with regurgitation of duodenal contents into the esophagus were not administered any carcinogen and were sacrificed some at the end of 8 weeks and others at 50 weeks for pathological examination. Hyperplasia was found in rats at 8 weeks, and the esophageal squamous cell carcinoma was found in rats at 50 weeks. The carcinomas were found exclusively in the area of the reflux esophagitis and were accompanied by severe dysplasia. These results suggested that alkaline reflux of duodenal contents was strongly correlated to the development of the esophageal squamous cell carcinoma.

Expression of neuron specific phosphatase, striatal enriched phosphatase (STEP) in reactive astrocytes after transient forebrain ischemia

We studied the distribution and change of striatal enriched phosphatase (STEP) in the gerbil hippocampus after transient forebrain ischemia. STEP was expressed in the perikarya and in neuronal processes; it was not detected in non-neuronal cells of control animals. After 5-min forebrain ischemia, STEP immunoreactivity (STEP-IR) was preserved for 2 days; it disappeared 4 and more days after ischemia with completion of delayed neuronal death (DND) in the CA1 subfield. Furthermore, only in the CA1 after ischemia, STEP was expressed in reactive astrocytes for 4 to 28 days, showing different patterns of glial fibrillary acidic protein (GFAP)-positive reactive astrocytes. After non-or less-than lethal ischemia, STEP expression in reactive astrocytes corresponded with the degree of neuronal degeneration. Immunoblot analysis of the CA1 subfield revealed the expression of three isoforms, STEP45, -56 and -61; their expression patterns changed with time after ischemia. These data suggest that neuronal STEP is preserved until cell degeneration after ischemia and that STEP is expressed in reactive astrocytes only after lethal ischemia, with different expression patterns for its isoforms. Of STEP45, -56 and -61, STEP61 was the most strongly expressed in the reactive astrocytes; both STEP45 and -61 were expressed in neurons and the expression of STEP56 was weak. STEP may play an important role not only in neurons but also in reactive astrocytes after ischemia, depending on neuronal degeneration.

Gelatin-containing diphtheria-tetanus-pertussis (DTP) vaccine causes sensitization to gelatin in the recipients

Gelatin-specific T cell response was performed to determine whether a series of vaccinations with gelatin-containing DTP is a primary sensitization process in gelatin allergy. Thirty-seven recipients with gelatin-containing DTP who developed adverse reactions after vaccination and eight recipients of DTP without gelatin who also developed adverse reactions were studied. In addition, 10 subjects receiving gelatin-containing vaccine and 10 subjects inoculated with non-gelatin vaccine who did not show any adverse reactions were also investigated. All subjects inoculated with gelatin-containing DTP vaccine showed positive T cell responses against gelatin, however, occurrence of adverse reactions did not correlate with T cell responses. We conclude that DTP vaccine containing gelatin induces sensitization to gelatin in the recipients, but the mechanism of local reactions remains unknown.

[Limited-form Wegener's granulomatosis without anti-neutrophil cytoplasmic antibody]

A 78-year-old woman was admitted because of dry cough and weight loss. A computed tomographic (CT) scan of the thorax showed multiple masses in both lungs with and without cavitation. No other organ lesions were detected. The patient was seronegative for antineutrophil cytoplasmic antibody (ANCA) and a routine sputum culture was normal. Because specimens from transbronchial and CT-guided transluminal lung biopsies disclosed non-specific granuloma with necrosis, an excisional biopsy of the mass by video-assisted thoracoscopic surgery was performed. The specimens contained geographic basophilic necrosis with palisading histiocytes, giant cells, and neutrophils. A limited form of Wegener's granulomatosis was diagnosed on the basis of the clinical and pathological features and effects of treatment.

Acetaminophen-induced immunosuppression associated with hepatotoxicity in mice

We investigated the influence of acetaminophen (APAP), an analgesic and hepatotoxic agent, on the immune system in mice. The activity of serum glutamic-pyruvic transaminase was markedly increased by about 200 fold compared to that of the vehicle control following intraperitoneal injection of 400 mg/kg of APAP. In vivo antibody-producing responses to SRBC was significantly inhibited by APAP in a dose-dependent manner, while in vivo T cell-independent antibody-producing responses to TNP-Ficoll was not inhibited. The addition of thymocytes from APAP-treated mice suppressed the response to SRBC in vitro. Thymocyte blastogenesis following mitogenic stimulation with concanavalin A was also inhibited by injection of APAP. The delayed-type hypersensitivity response and mixed lymphocyte reaction, which are used to evaluate cell-mediated immunity, were also significantly reduced after treatment with APAP. These results indicate that APAP suppresses the humoral and cell-mediated immune responses at a dose that causes liver injury.

Effects of light on the tritrophic interaction between kidney bean plants, two-spotted spider mites and predatory mites, Amblyseius womersleyi (Acari: Phytoseiidae)

By analyzing the volatiles from Tetranychus urticae-infested kidney bean plants (Phaseolus vulgaris) at different times for two days, we found that they were mainly produced in the light. Tetranychus urticae showed a higher oviposition rate and spent more time feeding during the day (in the light) than at night (in the dark). Infested leaves placed in the light attracted the predatory mite Amblyseius womersleyi, whereas those that were placed in the dark for at least 2 h in daytime did not. This indicates that presence or absence of light affects the production of herbivore-induced plant volatiles. Amblyseius womersleyi dispersed more frequently and consumed more T. urticae eggs during the day (in the light) than at night (in the dark), whereas their oviposition rate did not differ between day and night. Presence or absence of herbivore-induced plant volatiles in the surroundings did not affect dispersal, predation or oviposition rates of A. womersleyi. These results show that A. womersleyi's behavior coincides with the production pattern of herbivore-induced plant volatiles.

[A case of recurrent pancreatic cancer brought into a complete response by a multimodal treatment with intraarterial chemotherapy and radiotherapy]

We achieved a complete response of recurrent pancreatic cancer using a multimodal treatment with intravenous, oral and intraarterial chemotherapies and radiotherapy. A 55-year-old female patient had a recurrent pancreatic cancer, which had invaded the portal vein, 2 years after pancreatoduodenectomy. Angiography demonstrated prominent stenosis of the portal vein, which was enlarged by the insertion of a metalic stent to maintain blood flow to the liver. Chemotherapy included intravenous mitomycin C, 5-FU and 4'-epirubicin (EPI), oral UFT and cyclophosphamide, and intraarterial cisplatin, 5-FU and EPI through a catheter inserted into the celiac artery. Furthermore, the patient received a total of 50 Gy radiotherapy. Four months after the initiation of therapy, a computed tomography image demonstrated a complete disappearance of the recurrent tumor and a prominent decrease in the serum CA19-9 level. At present, 11 months have passed after the initiation of therapy, and she has been followed at our outpatient department without any symptoms of recurrence.

Stimulatory effect of dibutyryl cyclic GMP on acid secretion in mouse isolated stomach and on histamine release in gastric mucosal cells

We previously reported that endogenous nitric oxide (NO) is involved in the peripheral control of gastric acid secretion induced by some secretagogues, and that endogenous NO is involved in the acid secretion process via histamine release from histamine-containing cells. However, the stimulus-secretion coupling in the cells remains to be clarified. In the present study, we investigated the effect of dibutyryl cyclic GMP on gastric acid secretion in mouse isolated stomach and on histamine release in gastric mucosal cells, in comparison with those of dibutyryl cyclic AMP. Dibutyryl cyclic GMP (300 microM) produced a slight but significant increase of gastric acid secretion, which was completely inhibited by the histamine-H2 receptor antagonist famotidine. In contrast, dibutyryl cyclic GMP (1 mM) markedly inhibited histamine-induced acid secretion. Dibutyryl cyclic AMP (100 microM) produced a sustained increase of gastric acid secretion. The pretreatment with famotidine partially inhibited dibutyryl cyclic AMP-induced gastric acid secretion. Dibutyryl cyclic GMP and dibutyryl cyclic AMP significantly increased the histamine release from gastric mucosal cells. These results suggest that both intracellular cyclic GMP and cyclic AMP act as second messengers for histamine release in the histamine-containing cells, probably ECL cells. On the other hand, in gastric parietal cells, cyclic AMP has a stimulatory effect on gastric acid secretion, whereas cyclic GMP has an inhibitory effect.

Therapeutic efficacy of a new topoisomerase I and II inhibitor TAS-103, against both P-glycoprotein-expressing and -nonexpressing drug-resistant human small-cell lung cancer

We examined the effect of a novel topoisomerase I and II (topo I and II) inhibitor, TAS-103, on P-glycoprotein (P-gp)-expressing and -nonexpressing drug-resistant human small-cell lung cancer (SCLC) cells in vitro and in vivo. We observed that TAS-103 was effective in inhibiting in vitro proliferation of human SCLC (SBC-3 and H69) cells and their drug-resistant variants SBC-3/ADM or SBC-3/CDDP and H-69/VP, respectively. SBC-3/ADM and H-69/VP expressed high P-gp, whereas SBC-3/CDDP did not. TAS-103 also effectively reduced the tumor growth (more than 50% inhibition) of the parental as well as MDR SCLC cells grown SC in nude mice. Adriamycin (ADM) and cisplatin (CDDP), on the other hand, were effective only against the parental cells, while these drugs failed to inhibit the respective drug-resistant variants in vitro or in vivo. TAS-103 was observed to induce apoptosis dose dependently in the parental as well as drug-resistant SCLC cells as analyzed after 48 h of in vitro treatment, suggesting that the stabilization of cleavable topo I- or II-DNA complexes by topo I and II inhibitors like TAS-103 is followed by apoptosis of the cells. Overall, our study suggests that TAS-103 may have clinical application against drug-resistant human SCLC.