Accidental dental injury of radiolucent replacement teeth during intubation.
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Biomedical subjects
Publications and source records attributed to S Koyama.
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Quantitative analysis based on the percentage of positive cells by two-color flow cytometry was used to quantify the surface expression of epidermal growth factor receptor (EGFR), and exons v6 and v9 of CD44 splice variants on tumor. Almost all patients with primary gastric and esophageal carcinomas, and benign mucosa of the stomach and esophagus showed usually high levels of EGFR expression, a mean of approximately 60% of cells being positive. Metastatic gastric carcinoma showed significantly higher levels of EGFR expression, a mean of 80% of cells being positive. Reduced expression of EGFR was observed in irradiated esophageal carcinoma. Adenocarcinomas, including primary and metastatic lesions, or cancer cell lines of the stomach revealed consistently very low or undetectable levels of expression of exon v6 of the CD44 variant (CD44v) protein. However, CD44v containing exon v9 could be detected in normal gastric epithelium and primary gastric carcinoma as well as in six adenocarcinoma cell lines. Exon v9 is significantly overexpressed on metastatic adenocarcinoma cells obtained from malignant ascites. On the other hand, normal squamous epithelium and primary squamous cell carcinoma (SCC) of the esophagus, and two SCC cell lines showed coexpression of exons v6 and v9 of CD44v. The expression of the CD44v6 molecule was significantly reduced in the irradiated primary SCC, although CD44v9 expression on the primary SCC remained unchanged after the radiation therapy. These results suggest that up-regulation of EGFR and CD44v9 molecules on gastric carcinomas, especially metastatic adenocarcinomas, shows tumor growth and tumor progression. In addition, down-regulation of EGFR and CD44v6 molecules on irradiated esophageal carcinoma may be involved in the mechanisms suppressing tumor growth and metastatic potential.
A case of microphthalmia with Xp microdeletion is reported. The patient was a boy who showed bilateral microphthalmia with corneal opacities, hypospadias without evidence of hypogonadism, and a conduction disturbance of the heart (Wenckebach conduction). No skin lesion was discerned. High-resolution chromosome analysis revealed the karyotype of 46,X,del(X)(p22). The phenotype was considered to be microphthalmia with linear skin defects (MLS) syndrome without skin lesions. Polymerase chain reaction and fluorescence in-situ hybridization analyses revealed that the chromosome aberration resulted from an X;Y translocation: the presence of pseudoautosomal boundary Y and the sex-determining region of Y was confirmed, while Xp deletion involving the region distal to DXS1129 was ascertained. Thus the chromosome designation using the ISCN 1995 nomenclature is 46,X,der(X),t(X;Y)(p22.13;q11.2). Despite the absence of skin lesions, the Xp deletion of our patient corresponded to those of previously reported typical cases of MLS syndrome. Our observation further supports the current hypothesis that the phenotypic variation of MLS syndrome represents tissue-different X inactivation rather than different genetic effects of two contiguous genes.
Eosinophils and increased production of nitric oxide (NO) and superoxide, components of peroxynitrite, have been implicated in the pathogenesis of a number of allergic disorders including asthma. Peroxynitrite induced protein nitration may compromise enzyme and protein function. We hypothesized that peroxynitrite may modulate eosinophil migration by modulating chemotactic cytokines. To test this hypothesis, the eosinophil chemotactic responses of regulated on activation, normal T cell expressed and secreted (RANTES) and interleukin (IL)-5 incubated with and without peroxynitrite were evaluated. Peroxynitrite-attenuated RANTES and IL-5 induced eosinophil chemotactic activity (ECA) in a dose-dependent manner (P < 0.05) but did not attenuate leukotriene B4 or complement-activated serum ECA. The reducing agents deferoxamine and dithiothreitol reversed the ECA inhibition by peroxynitrite, and exogenous L-tyrosine abrogated the inhibition by peroxynitrite. PAPA-NONOate, a NO donor, or superoxide generated by lumazine or xanthine and xanthine oxidase, did not show an inhibitory effect on ECA. The peroxynitrite generator, 3-morpholinosydnonimine, caused a concentration-dependent inhibition of ECA. Peroxynitrite reduced RANTES and IL-5 binding to eosinophils and resulted in nitrotyrosine formation. These findings are consistent with nitration of tyrosine by peroxynitrite with subsequent inhibition of RANTES and IL-5 binding to eosinophils and suggest that peroxynitrite may play a role in regulation of eosinophil chemotaxis.
In this report, antitumor effects of YoshixolTR in vivo and in vitro were investigated in B16 melanoma cells. For in vivo experiments, the present study shows a dramatic inhibition of tumor growth of B16 melanoma transplanted on the leg or intraperitoneal cavity after treatment with YoshixolTR intraperitoneally. A proliferation of B16 cells in vitro was inhibited by YoshixolTR in a dose-and time-dependent manner. YoshixolTR induced apoptosis-like cell death in histological observations (phase-contrast, scanning and transmission electron microscopy), DNA fragmentation, and a smaller increase in lactate dehydrogenase (LDH) as a marker of cell leakage. Immunohistochemical investigation of cytoskeletal components, such as actin and tubulin, showed a cell wall disruption of B16 melanoma cells and a nuclear extrusion after the treatment with YoshixolTR. Treatment with YoshixolTR in vitro showed an arrest at the G0/G1 stage of the cell cycle, followed by a flow cytometric measurement. As a possible physiological mechanism of YoshixolTR on B16 melanoma cells, intracellular Ca++ was measured with Fura-2 technique. An adequate concentration of YoshixolTR, which induces apoptosis-like cell death, showed a decrease in intracellular free Ca++ concentration. In conclusion, YoshixolTR has an antitumor potency with a new biological mechanism of cell growth, proliferation, and differentiation, including cellular signalling pathways, and is a new candidate for an ideal chemotherapeutic agent against malignant tumors.
In this report, antiproliferative effects of YoshixolTR in vitro and in vivo were investigated in murine L1210 cells. A proliferation of L1210 cells in vitro was inhibited by YoshixolTR in a dose- and time-dependent manner. This inhibition showed an arrest at the G0/G1 stage of the cell cycle, followed by a flow cytometric measurement. YoshixolTR induced apoptosis-like cell death identified by histological observations (scanning electron and transmission electron microscopy), DNA fragmentation, and a smaller increase in lactate dehydrogenase (LDH). In the in vivo experiments, YoshixolTR (5 microl/kg of body weight, on days 1, 3, and 5) was injected intraperitoneally in mice inoculated with L1210 cells. No marked prolongation of survival occurred between the control group and treated group. However, a survival curve in the treated group showed a shift toward a possible longer survival time. Additionally, on the basis of apoptosis-like cell death due to YoshixolTR as indicated above, a possibility of immunotherapy as a tumor vaccine has been examined. A vaccination of rabbit anti-serum, which consisted of components from the L1210 cells killed by YoshixolTR, produced a dramatic improvement of viability in the leukemic mice. In conclusion, YoshixolTR has an anti-leukemic potency with a new biological mechanism and an inductive potency of super-antigens as immunotherapeutic agents against malignant tumors.
We studied the effects of sleep on auditory evoked magnetic fields following pure tone stimulation applied to the right ear of 10 healthy normal volunteers to investigate the changes in the processing of auditory perception in the primary auditory cortex. Dual 37-channel biomagnetometers were used to record auditory evoked magnetic fields over the bilateral temporal lobes in response to presented tones. Auditory evoked magnetic fields were compared for three stimulus frequencies (250, 1000 and 4000 Hz) and three sleep stages (awake state, sleep stages 1 and 2). Four main components, M50, M100, M150 and M200, were identified with latencies of approximately 50, 100, 150 and 200 ms, respectively. The latency of each component had a tendency to be prolonged with the depth of sleep stage in all frequencies. The amplitude ratios of the early-latency components (M50 and M100) showed a tendency of reduction compared with the same components in the awake state. By contrast, the amplitude ratios of the long-latency components (M150 and M200) were significantly enhanced with an increase in the sleep stage compared with the same components in the awake state. The equivalent current dipoles of all components in all conditions were detected at the superior temporal cortex (the primary auditory cortex). As for the changes in the equivalent current dipole location of each component, the equivalent current dipole was detected in the more posterior and medial region in responses to the high-frequency tone (1000 and 4000 Hz) compared with those to 250 Hz tone stimulation. Although the equivalent current dipoles of the early-latency components (M50 and M100) were in regions more anterior and superior compared to those in the awake state, there was no consistent tendency of changes in equivalent current dipole locations between each sleep stage in the late-latency components (M150 and M200). These findings are probably due to the difference in generating mechanisms between the early- and late-latency components.
Although the cytotoxicity of lipopolysaccharide (LPS) derived from Pseudomonas aeruginosa, i.e. Limulus amoebocyte lysate activity, is less potent than that from Escherichia coli 0127:B8, P. aeruginosa induces prominent sustained lung inflammation, as in cystic fibrosis. The present study was designed to examine the potential for several LPSs obtained from E. coli and P. aeruginosa to release monocyte chemotactic activity (MCA) from lung cells. LPSs differentially stimulated A549 cells, BEAS-2B cells and lung fibroblasts to release MCA (P. aeruginosa >E. coli 0127:B8 from Difco >055:B5 from Sigma >026:B6 (Sigma)). E. coli 0127:B8 (Sigma) and 0111:B4 (Sigma) did not stimulate these cells. MCA was determined by means of checkerboard analysis. Molecular sieve column chromatography revealed four chemotactic peaks. The release of MCA was inhibited by cycloheximide and lipoxygenase inhibitors. Experiments with blocking antibodies suggested that much of the MCA was secondary to monocyte chemoattractant protein-1 (MCP-1) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Thus, the concentrations of these chemoattractants were examined and it was found that the potency of the various LPSs to stimulate MCA closely paralleled their potency in releasing MCP-1 and GM-GSF. Serum augmented the release of MCP-1 and GM-CSF. However, the differences among LPSs from E. coli and P. aeruginosa in stimulating A549 cells were observed. These data suggest that Pseudomonas aeruginosa lipopolysaccharide may stimulate lung cells to release more monocyte chemotactic activity than lipopolysaccharides derived from Escherichia coli, leading to sustained prominent lung inflammation.
The case reported is of an 88 yr old female with hypertension and respiratory distress. A chest radiograph revealed a widening of the upper mediastinum. Computed tomographic scanning revealed tracheal compression by the innominate artery, which was elongated and curved. After intubation, she was treated with antihypertensive drugs. This resulted in the remarkable recovery of the patient from respiratory distress. To the authors' knowledge, this is the first reported case of respiratory distress owing to tracheal compression by elongation and curvature of the innominate artery.
Theophylline inhibits eosinophilic infiltration into the bronchial wall. It is unknown whether this is mediated by a cyclic adenosine monophosphate (c-AMP)-dependent reduction in eosinophil chemotactic activity (ECA) from bronchial epithelial cells (BEC). Therefore the effect of a beta2-agonist, procaterol and theophylline on the release of ECA from a BEC line, BEAS-2B was evaluated in response to interleukin (IL)-1beta and tumour necrosis factor-alpha (TNF-alpha). ECA was assessed using a blind-well chemotactic chamber, and the release and gene expression of cytokines were evaluated by means of enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction. IL-1beta and TNF-alpha stimulated the release of ECA from BEAS-2B cells in a dose- and time-dependent manner. Procaterol and theophylline directly inhibited eosinophil migration to IL-1beta and TNF-alpha-conditioned medium. The pretreatment of BEAS-2B cells with the same concentrations of procaterol inhibited the release of ECA in a dose-dependent fashion. Anti-IL-8, anti-regulated on activation, normal T-cell expressed and secreted (RANTES), and anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited ECA. Procaterol inhibited the release of RANTES, GM-CSF and IL-8 in a dose-dependent fashion. The effect of theophylline was less potent. Procaterol augmented cAMP levels in BEAS-2B cells in a time- and dose-dependent manner. The expression of IL-8, RANTES, and GM-CSF messenger ribonucleic acid was not inhibited by procaterol and theophylline. These data indicate that procaterol and theophylline may directly inhibit eosinophil migration and that procaterol may further inhibit the release of eosinophil chemotactic activity from BEAS-2B cells via a cyclic adenosine monophosphate-dependent mechanism. This warrants further studies on the involvement of bronchial epithelial cells in the anti-inflammatory effects of procaterol and theophylline in patients with asthma.
1. Tranilast, first developed as an anti-allergic drug, has been reported to inhibit vascular endothelial growth factor (VEGF)-induced angiogenesis and vasopermeability. To further clarify the inhibitory mechanism, we investigated the effects of tranilast on VEGF binding and subsequent intracellular signalling pathway linked to angiogenic activities and gene expression of bovine retinal microcapillary endothelial cells. 2. Tranilast significantly (P<0.01) inhibited VEGF, basic fibroblast growth factor (bFGF), and hypoxia conditioned media-induced BREC proliferation in a dose dependent manner with IC50's of 22, 82 and 10 microM, respectively. 3. VEGF-induced migration was also inhibited by tranilast in a dose dependent manner, with IC50 of 18 microM, and complete inhibition was observed at 300 microM (P<0.01). Tranilast suppressed VEGF-induced tube formation in a dose dependent manner with maximum (46%) inhibition observed at 300 microM (P<0.05). 4. Tranilast inhibited phorbol myristate acetate (PMA)-dependent stimulation of [3H]-thymidine incorporation and VEGF- and PMA-induced gene expression of integrin alpha v and c-fos in BREC. 5. Tranilast suppressed VEGF- and PMA-stimulated PKC activity in BREC. 6. Tranilast did not affect VEGF binding or VEGF-induced phosphorylation of tyrosine residues of VEGF receptor- and phospholipase Cgamma and their associated proteins. 7. These data suggest that tranilast might prove an effective inhibitor to prevent retinal neovascularization in ischaemic retinal diseases, and that its inhibitory effect might be through suppression of PKC-dependent signal transduction in BREC.
CD56+ angiocentric lymphoma has currently been recognized as a distinct clinical entity which is the prototype of the putative NK cell lymphomas. A 16-year-old Japanese girl with advanced CD56+ angiocentric lymphoma received high-dose chemotherapy supported with syngeneic peripheral blood stem cell transplantation (PBSCT). Prior to syngeneic PBSCT, she received six cycles of conventional chemotherapy before transplantation, resulting in a partial response. PBSC were mobilized with granulocyte colony-stimulating factor (G-CSF) and collected from her identical twin. High-dose cyclophosphamide, MCNU, etoposide, and carboplatin were used for pretransplant conditioning. Syngeneic PBSCT was well tolerated. She achieved complete remission and is now surviving in continuous complete remission for more than 30 months after syngeneic PBSCT. Thus, marrow-ablative chemotherapy facilitated by autologous or allogeneic PBSCT should be considered as part of the primary therapy for poor prognosis NK cell lymphomas.
The purpose of the present study was to examine the efficacy of U-74006F, a 21-aminosteroid, on lung dysfunction induced by endotoxaemia in awake sheep with lung lymph fistula and haemodynamic monitoring. We measured pulmonary haemodynamics, lung lymph balance, circulating leucocyte count, arterial blood gas tensions, and levels of thromboxane (Tx) B2 and 6-keto-prostaglandin (PG) F1 alpha in plasma and lung lymph. We performed two experiments. In experiment 1 (n = 6), we intravenously infused Escherichia coli lipopolysaccharide endotoxin (1 microgram/kg) over 30 min and observed the parameters over 5 h. In experiment 2 (n = 6), we pretreated sheep with an intravenous bolus of U-74006F (2 mg/kg) 30 min before the infusion of endotoxin in the same manner of experiment 1, and continuously infused U-74006F (0.5 mg/kg per h) over 5 h after the bolus during the experiment. The U-74006F significantly suppressed the early pulmonary hypertension, the late increase in pulmonary permeability and the elevations of TxB2 and 6-keto-PGF1 alpha levels in plasma and lung lymph during the early period following endotoxaemia, although the compound did not change the time course of leucocytopenia and hypoxaemia. These findings suggest that the administration of U-74006F attenuates the lung dysfunction induced by endotoxaemia in awake sheep.
We describe a patient with the asymptomatic form of Brugada syndrome. His electrographical, electropharmacological, and electrophysiological characteristics were similar to those reported in patients with the symptomatic form of Brugada syndrome. We believe that he has the same arrhythmogenic substrate as that of patients with Brugada syndrome. The fact that he had no episode of spontaneous ventricular fibrillation might be explained by his absence of the triggering factors.
Although bleomycin, an antineoplastic drug, is used in the treatment of a variety of tumors, the mechanisms of bleomycin-induced lung injury and fibrosis are not fully elucidated. We postulated that bleomycin might stimulate A549 cells, a type II pneumocyte cell line, to release neutrophil and monocyte chemotactic activities (NCA and MCA, respectively). To test this hypothesis, A549 cell supernatant fluids were harvested and evaluated for NCA and MCA. A549 cell supernatant fluids showed NCA and MCA in response to bleomycin in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis revealed that both NCA and MCA were predominantly chemotactic. Partial characterization of the released NCA and MCA showed that the activities were partially heat labile, trypsin digested, and predominantly ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of chemotactic activities significantly. Molecular-sieve column chromatography revealed that the released activities were heterogeneous. However, low-molecular-weight activity was prominent. Leukotriene B4-receptor antagonist, anti-interleukin-8, anti-granulocyte colony-stimulating factor, and anti-monocyte chemoattractant protein-1 antibodies attenuated the chemotactic activities. Immunoreactive leukotriene B4 receptor, interleukin-8, granulocyte colony-stimulating factor, and monocyte chemoattractant protein-1 significantly increased in supernatant fluids in response to bleomycin. These data demonstrate that bleomycin stimulates type II epithelial cells to release chemotactic activities and plays a role in inflammatory cell recruitment into the lung.
Peroxynitrite, an oxidant generated by the interaction between superoxide and nitric oxide (NO), can nitrate tyrosine residues, resulting in compromised protein function. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that attracts monocytes and has a tyrosine residue critical for function. We hypothesized that peroxynitrite would alter MCP-1 activity. Peroxynitrite attenuated MCP-1-induced monocyte chemotactic activity (MCA) in a dose-dependent manner (P < 0.05) but did not attenuate leukotriene B4 or complement-activated serum MCA. The reducing agents dithionite, deferoxamine, and dithiothreitol reversed the MCA inhibition by peroxynitrite, and exogenous L-tyrosine abrogated the inhibition by peroxynitrite. PAPA-NONOate, an NO donor, or superoxide generated by xanthine and xanthine oxidase did not show an inhibitory effect on MCA induced by MCP-1. The peroxynitrite generator 3-morpholinosydnonimine caused a concentration-dependent inhibition of MCA by MCP-1. Peroxynitrite reduced MCP-1 binding to monocytes and resulted in nitrotyrosine formation. These findings are consistent with nitration of tyrosine by peroxynitrite, with subsequent inhibition of MCP-1 binding to monocytes, and suggest that peroxynitrite may play a role in regulation of MCP-1-induced monocyte chemotaxis.
Accumulation of monocytes and neutrophils and fibrous distortion of the airway are characteristics of airway disease secondary to smoking. The presence of inflammatory cells and fibrosis correlate, and, therefore, we postulated that lung fibroblasts might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, human fetal lung (HFL1) fibroblasts were cultured, and the supernatant fluid was evaluated for neutrophil (NCA) and monocyte (MCA) chemotactic activities with a blind well chamber technique. HFL1 fibroblasts released chemotactic activity in response to smoke extract in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis showed that the activity was predominantly chemotactic. Partial characterization of the released chemotactic activity revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of both NCA and MCA. Molecular-sieve chromatography revealed that NCA and MCA were heterogeneous. NCA was inhibited by anti-human interleukin (IL)-8 and anti-granulocyte colony-stimulating factor antibodies and a leukotriene (LT) B(4)-receptor antagonist. Anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) and anti-monocyte chemoattractant protein (MCP)-1 antibodies and an LTB(4)-receptor antagonist inhibited MCA. Immunoreactive IL-8, granulocyte colony-stimulating factor, GM-CSF, and MCP-1 significantly increased in culture supernatant fluid in response to smoke extract. Finally, smoke extract augmented the expression of mRNAs of IL-8, GM-CSF, and MCP-1. These data demonstrate that lung fibroblasts release NCA and MCA in response to smoke extract and suggest that lung fibroblasts may modulate the inflammatory cell recruitment into the lung.
In rabbit livers, it is not well known which segments of the hepatic vasculature are predominantly contracted by various vasoconstrictors. We determined effects of histamine, norepinephrine, and KCl on hepatic vascular resistance distribution in isolated rabbit livers perfused via the portal vein with 5% albumin-Krebs solution at a constant flow rate. Hepatic capillary pressure was measured by double vascular occlusion pressure (Pdo) and was used to determine portal (Rpv) and hepatic venous (Rhv) resistances. A bolus injection of either histamine or norepinephrine dose-dependently increased portal venous pressure but not Pdo, resulting in a dose-dependent increase in Rpv and no changes in Rhv. KCl (50 mM), when injected in anterogradely perfused livers, contracted the presinusoidal vessels selectively with liver weight loss. Although KCl significantly increased Rhv in retrogradely perfused livers, the increase in Rpv by 400% of baseline predominated over the increase in Rhv by 85% of baseline. In the retrogradely perfused livers, KCl produced an initial liver weight loss followed by a profound weight gain. We conclude that histamine and norepinephrine selectively contract the presinusoidal vessels. The results on KCl effects suggest that this selective presinusoidal constriction might be possibly due to predominant distribution of functionally active vascular smooth muscle in the presinusoidal vessels rather than the hepatic vein in rabbit livers.