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T Tsuji

Publications and source records attributed to T Tsuji.

At least 55 records · Page 3Linked to original sources

Ultracytochemical study of medullary bone calcification in estrogen injected male Japanese quail.

Fine structural and cytochemical studies were performed to clarify the pattern of medullary bone calcification, specifically in relation to sulfated glycosaminoglycans, by using estrogen-induced medullary bone of male Japanese quails. Tibiae were collected at 4 and 7 days after estrogen treatment. Medullary bone had developed inward toward the marrow cavity, and calcification had begun near the cortical bone and deeper parts of the trabeculae, accompanied by wide osteoid at extending tips and surface areas of the trabeculae. Sulfated glycosaminoglycans, detected by high iron diamine (HID), were distributed in the matrix in a pattern similar to that of calcified matrix of the trabeculae. Cortical bone was negatively stained by HID. In undecalcified specimens, calcified nodules were seen in areas undergoing calcification. Globular structures composed of fine filamentous materials, a marginal dense layer, and central core, were also observed in the matrix of decalcified specimens. Both the calcified nodules and globular structures showed the same distribution pattern, i.e., they were dispersed at surface areas and coalesced in the deeper areas of the matrix. The globular structures were exclusively positive for HID-thiocarbohydrazide-silver protein (HID-TCH-SP) stain, indicating the localization of sulfated glycosaminoglycans. These results strongly suggest that medullary bone calcification progresses by the coalescence of calcified nodules and that sulfated glycosaminoglycans play an important role for the regulation of globular calcification.

Animals↗

The E-cadherin gene is silenced by CpG methylation in human oral squamous cell carcinomas.

Reduction of E-cadherin strongly relates to invasiveness and metastasis in vitro. To clarify CpG methylation around the promoter region of the E-cadherin gene in oral squamous cell carcinoma (SCC), we examined the DNA samples of various human SCC cell lines and primary oral SCC tissues by methylation-specific polymerase chain reaction (MSP). CpG methylation of the E-cadherin gene markedly correlated to the reduction of E-cadherin expression in human oral SCC cell lines. In primary oral SCC tissues, only 1 of 5 preserved E-cadherin-expressing tissues was methylated, whereas methylation was found in 17 (94.4%) of 18 E-cadherin-reduced tissues. Our results suggest that reduction of E-cadherin expression is associated with CpG methylation of the E-cadherin gene promoter. We recently established two cell lines with high and low metastatic potential, UM1 and UM2, from SCC primary tongue tissue of a patient. E-cadherin expression of high-metastatic UM1 was clearly lower than that of low-metastatic UM2, and MSP results showed CpG methylation in the UM1 but not the UM2 cell line. To investigate whether demethylation of CpG methylation of the E-cadherin gene could restore expression and function of E-cadherin, we treated UM1 with the demethylating agent 5-azacytidine (5-aza) and found that E-cadherin expression was indeed restored by demethylation. Moreover, in the demethylated UM1, invasion of the collagen gel was clearly suppressed compared with the untreated UM1. These results suggested that inactivation of E-cadherin expression resulted from CpG methylation of the gene promoter; a correlation between CpG methylation of the E-cadherin gene promoter and invasive potential was also suggested.

Antimetabolites, Antineoplastic↗

A critical role for mouse CXC chemokine(s) in pulmonary neutrophilia during Th type 1-dependent airway inflammation.

Ag-specific Th1 and Th2 cells have been demonstrated to play a critical role in the induction of allergic diseases. Here we have investigated the precise mechanisms of Th1-induced airway inflammation. Airway inflammation was induced in BALB/c mice by transfer of freshly induced OVA-specific Th1 or Th2 cells followed by OVA inhalation. In this model, both Th1 and Th2 cells induced airway inflammation. The former induced neutrophilia in airways, whereas the latter induced eosinophilia. Moreover, we found that Th1 cells induced more severe airway hyperresponsiveness (AHR) than Th2 cells. The eosinophilia induced by Th2 cell infusion was almost completely blocked by administration of anti-IL-5 mAb, but not anti-IL-4 mAb. In contrast, Th1-induced AHR and pulmonary neutrophilia were inhibited by the administration of anti-human IL-8R Ab, which blocks the function of mouse CXC chemokine(s). These findings reveal a critical role of mouse CXC chemokine(s) in Th1-dependent pulmonary neutrophilia and AHR.

Administration, Inhalation↗

Effects of molecular structure on the stability of a thermotropic liquid crystal. Gas electron diffraction study of the molecular structure of phenyl benzoate.

As a model of the core of molecules forming liquid crystals, the molecular structure of phenyl benzoate (Ph-C(=O)-O-Ph) at 409 K was determined by gas electron diffraction, and the relationship between the gas-phase structures of model compounds and the nematic-to-liquid transition temperatures was studied. Structural constraints were obtained from RHF/6-31G ab initio calculations. Vibrational mean amplitudes and shrinkage corrections were calculated from the harmonic force constants given by normal coordinate analysis. Thermal vibrations were treated as small-amplitude motions, except for the phenyl torsion, which was treated as a large-amplitude motion. The potential function for torsion was assumed to be V(phi(1),phi(2)) = V(12)(1 - cos 2phi(1))/2 + V(14)(1 - cos 4phi(1))/2 + V(22)(1 - cos 2phi(2))/2, where phi(1) and phi(2) denote the torsional angles around the C-Ph and O-Ph bonds, respectively. The potential constants (V(ij)()/kcal mol(-)(1)) and the principal structure parameters (r(g)/A, angle(alpha)/deg) with the estimated limits of error (3sigma) are as follows: V(12) = -1.3 (assumed); V(14) = -0.5(9); V(22) = 3.5(15); r(C=O) = 1.208(4); r(C(=O)-O) = 1.362(6); r(C(=O)-O) - r(O-C) = -0.044 (assumed); r(C(=O)-C) = 1.478(10); = 1.396(1); angleOCO = 124.2(13); angleO=CC = 127.3(12); angleCOC = 121.4(22); ( angleOCC(cis) - angleOCC(trans))/2 = 3.0(15); ( angleC(=O)CC(cis) - angleC(=O)CC(trans))/2 = 4.8(17), where < > means an average value and C-C(cis) and C-C(trans) bonds are cis and trans to the C(=O)-O bond, respectively. The torsional angle around the O-Ph bond was determined to be 64(+26,-12) degrees. An apparent correlation was found between the contributions of the cores to the clearing point of liquid crystals and the gas-phase structures of model compounds of the cores of mesogens, i.e., phenyl benzoate, trans-azobenzene (t-AB), N-benzylideneaniline, N-benzylideneaniline N-oxide (NBANO), trans-azoxybenzene (t-AXB), and trans-stilbene. The structures of t-AB, NBANO, and t-AXB have been obtained by our research group.

Journal Article↗

Long-term persistence of cellular immunity to Oka vaccine virus induced by pernasal co-administration with Escherichia coli enterotoxin in mice.

A mutant of Escherichia coli enterotoxin induced cellular immunity to a live varicella vaccine (the Oka strain) as a mucosal adjuvant in mice. The persistence of this cellular immunity was investigated. A commercially available live Oka vaccine virus and toxin were administered once simultaneously via the nasal route, in mice. Ten or 12 months later, a delayed-type hypersensitivity to the vaccine virus was detected by footpad test, but an antibody neutralizing the varicella-zoster virus was not. When spleen cells from mice immunized with the vaccine and toxin were re-stimulated by live vaccine in vitro, their thymidine uptake and IL-2 production were higher than those from mice immunized with the vaccine alone, but lower than those of spleen cells prepared from mice 2 months after nasal administration. Production of IL-4 in these cells, however, was not induced by re-stimulation in vitro. These results suggest that although humoral immunity for Oka vaccine virus is only weakly induced by one co-administration of the vaccine and toxin, cellular immunity is induced and maintained over 1 year, though it declines with age. The nasal administration of the vaccine and toxin might be effective for maintaining cellular immunity to the varicella-zoster virus long term.

Administration, Intranasal↗

ICOS costimulation requires IL-2 and can be prevented by CTLA-4 engagement.

We investigated the relationship between ICOS, CD28, CTLA-4, and IL-2 to gain a better understanding of this family of costimulatory receptors in the immune response. Using magnetic beads coated with anti-CD3 and varying amounts of anti-ICOS and anti-CTLA-4 Abs, we show that CTLA-4 ligation blocks ICOS costimulation. In addition to inhibiting cellular proliferation, CTLA-4 engagement prevented ICOS-costimulated T cells from producing IL-4, IL-10, and IL-13. Both an indirect and direct mechanism of CTLA-4's actions were examined. First, CTLA-4 engagement on resting cells was found to indirectly block ICOS costimulation by interferring with the signals needed to induce ICOS cell surface expression. Second, on preactivated cells that had high levels of ICOS expression, CTLA-4 ligation blocked the ICOS-mediated induction of IL-4, IL-10, and IL-13, suggesting an interference with downstream signaling pathways. The addition of IL-2 not only overcame both mechanisms, but also greatly augmented the level of cellular activation suggesting synergy between ICOS and IL-2 signaling. This cooperation between ICOS and IL-2 signaling was explored further by showing that the minimum level of IL-2 produced by ICOS costimulation was required for T cell proliferation. Finally, exogenous IL-2 was required for sustained growth of ICOS-costimulated T cells. These results indicate that stringent control of ICOS costimulation is maintained initially by CTLA-4 engagement and later by a requirement for exogenous IL-2.

Abatacept↗

Initial and long-term results of directional coronary atherectomy in unprotected left main coronary artery.

Angioplasty in the unprotected left main coronary artery (LMCA) has been controversial. Recently, several studies have suggested that new procedures and devices such as directional coronary atherectomy (DCA) and stents may change this situation. Although there are many reports of unprotected LMCA stenting, there are few reports of DCA of this lesion. Therefore, initial and long-term results were evaluated in 101 patients who underwent DCA for unprotected LMCA in our hospital. Emergency procedures were performed in 15 patients and electively in 86 patients. Scheduled angiographic follow-up was routinely performed, and all patients were clinically followed for >4 months after DCA. Technical success was achieved in 99%, and in-hospital outcomes were cardiac death (2%), noncardiac death (4%), Q-wave myocardial infarction (1%), non-Q-wave myocardial infarction (8.9%), coronary artery bypass grafting (0%), and repeat angioplasty (4%). In-hospital results varied considerably, depending on presentation. In-hospital mortality was significantly higher in the emergency, left ventricular ejection fraction < or =35%, and high-risk surgical subgroups. The angiographic restenosis rate was 20.4% at follow-up, and its predictor was postminimal lumen diameter by multivariate analysis. Mean clinical follow-up was 2.8 years; estimated 1- and 3-year survival rates were 87% and 80.7%, respectively. The cardiac survival rate of the low-risk surgical subgroup was significantly higher than that of the high-risk surgical subgroup (p <0.05). Thus, our data show that DCA can be performed safely and effectively in unprotected LMCA with an acceptable low restenosis rate and high survival rate.

Adult↗

Immunohistochemical investigation of pulmonary surfactant-associated protein A in fatal poisoning.

To evaluate the immunohistochemical distribution of pulmonary surfactant-associated protein A (SP-A) in fatal poisoning in relation to the effects of drugs and poisons on respiratory function, 42 forensic autopsy cases were examined by scoring the staining intensity. The highest scores of SP-A staining, with dense granular deposits (aggregates) in the intra-alveolar space, were observed in fatalities from pancuronium bromide (muscle relaxant) injection and petroleum (butane) gas inhalation. Poisoning with organophosphate pesticides and arsenic (ingestion) showed a second grade SP-A score. However, The SP-A scores were relatively low in ethanol and sedative-hypnotic intoxication. Carbon monoxide intoxication showed a varied degree of SP-A score, and the aggregated SP-A score tended to be higher in cases of lower blood carboxyhemoglobin concentration. A varied SP-A score was also observed in methamphetamine fatalities, in which the score was relatively low in cases with a higher serum drug level. Increase of SP-A was not always associated with the intra-alveolar effusion or hemorrhages. The above-described observations suggested that the immunohistochemical score of SP-A may be a possible indication for intensity and duration of drug/poison-dependent respiratory distress.

Adolescent↗

Expression of Nov, CYR61 and CTGF genes in human hepatocellular carcinoma.

CCN family genes, Nov, CYR61 and CTGF, are immediate-early genes expressed in fibroblasts following growth stimuli. Aberrant expression of Nov has been found in human Wilms' tumor, and suggested to be involved in tumorigenesis. The aim of our experiments is to examine the expression of CCN family genes in human hepatocellular carcinomas (HCCs) and find the correlation of these gene expressions with clinicopathological parameters. A pair of tumor and surrounding non-tumor tissues were obtained from 23 patients with HCC and six with metastatic liver tumor. Total cellular RNA isolated from tissues was analyzed for the presence of mRNA of CCN family genes by the reverse-transcription polymerase chain reaction. Nov, CYR61 and CTGF mRNA were identified in 17 (73.9%), 17 (73.9%), six (26.1%) tumors, and in nine (39.1%), 16 (69.6%), one (4.3%) surrounding non-tumor tissues of 23 patients with HCC. No significant difference was found in clinicopathological parameters between cases with HCC negative and positive for these gene expressions. The prevalence of Nov and CTGF expression in HCC is significantly higher than those in surrounding non-tumor. The same tendency was found in metastatic tumors. These results suggest that Nov and CTGF is associated with the development of tumors in the liver.

Journal Article↗

Novel adhesion prevention membrane based on a bioresorbable copoly(ester-ether) comprised of poly-L-lactide and Pluronic: in vitro and in vivo evaluations.

Block copolymers consisting of poly(L-lactide) (PLLA) and poly(oxyethylene-co-oxypropylene), with various compositions, were synthesized and characterized in vitro and in vivo for their application as postoperative adhesion prevention membranes. It was found that the flexibility and degradability of the cast films of the block copolymers grew with increasing Pluronic F68 [PN; poly(oxyethylene-co-oxypropylene] composition. The receding contact angle of the copolymer films against water became lower than that of the PLLA film, because the surface was predominantly covered with more hydrophilic PN segments in a wet state. This surface property significantly affects the cell attachment property of the copolymer films, and the fibroblasts cultured on the films exhibit a spheroid-like morphology. The copolymer films subcutaneously implanted in the back of rats induced milder tissue responses compared with PLLA homopolymers, because of the increased surface hydrophilicity in the former. In vivo evaluation using a uterus horn model in rats revealed that the performance of these copolymer films as an adhesion-prevention membrane is comparable to that of a conventionally utilized membrane of oxidized regenerated cellulose. These results indicate that the copolymer films are biocompatible materials with controllable mechanical properties and biodegradability as adhesion-prevention membranes.

3T3 Cells↗

Effectiveness and safety of mutant Escherichia coli heat-labile enterotoxin (LT H44A) as an adjuvant for nasal influenza vaccine.

The effectiveness and safety of mutant Escherichia coli heat-labile enterotoxin, LT H44A (His to Arg substitution at position 44 from the N-terminus of the A1 fragment of the A subunit) as an adjuvant for nasal influenza vaccine were examined. (1) When 0.2 microg of LT H44A, together with 0.2 microg of influenza A/PR/8/34 virus (PR8, H1N1) vaccine, was administered intranasally into BALB/c mice (twice, 4 weeks apart), anti-PR8 hemagglutinin (HA) IgA and IgG antibody (Ab) responses were induced at levels that were sufficient to provide either complete protection against infection with a small volume of PR8 virus suspension or partial protection against infection with a lethal dose of the suspension. The dose of the mutant LT and vaccine used here (0.2 microg/ 20 g doses mouse) corresponded to the estimated dose per person, i.e. 0.1 mg/10 kg body weight. (2) Using these vaccination conditions, no additional total IgE Ab responses were induced. (3) The mutant was confirmed to be less toxic than the native LT when the toxicity was analyzed either using Y1 adrenal cells in vitro (1/483 EC(50)) or by an ileal loop test. (4) One hundred micrograms of the mutant, administered intranasally or intraperitoneally into guinea-pigs (Heartley strain, 0.3-0.4 kg), caused no body-weight changes 7 days after administration, although 100 microg of the native LT administered intraperitoneally caused death in all guinea-pigs due to diarrhea within 2 days. The intranasal administration of 100 microg of the mutant resulted in almost no pathological changes in the nasal mucosa 3 days after administration. These results suggest that LT H44A, which can be produced in high yields in an E. coli culture (about 5 mg/l), could be used as one of the effective and safe adjuvants for nasal influenza vaccine in humans.

Adjuvants, Immunologic↗

Induction of epithelial differentiation and DNA demethylation in hamster malignant oral keratinocyte by ornithine decarboxylase antizyme.

The hamster ornithine decarboxylase antizyme (ODC-Az) cDNA was transfected into the hamster malignant oral keratinocyte cell line, HCPC-1. Ectopic expression of ODC-Az resulted in the reversion of malignant phenotypes and alteration of DNA methylation status of CCGG sites. The phenotypes examined include ODC enzymatic activity, doubling time, morphological change, anchorage dependent growth, tumorigenicity in nude mice, induction of epithelial differentiation marker protein (involucrin), and change of cell cycle position. Comparison of CCGG DNA methylation status of the ODC-Az and control vector transfectants revealed a significant increase in demethylation of 5-methyl cytosines (m5C) of CCGG sites in the ODC-Az transfectants. Ectopic expression of ODC-Az gene in hamster malignant oral keratinocytes led to reduce ODC activity and the subsequent demethylation of 5-methyl cytosines, presumably via the ODC/ polyamines/ decarboxylated S-adenosylmethionine (dc-AdoMet) pathways. Our data suggest that ODC-Az shared the same pathway of polyamines/ dc-AdoMet/DNA methyltransferase (DNA MTase). We propose that ODC-Az mediates a novel mechanism in tumor suppression by DNA demethylation and presumably re-activation of key cellular genes silenced by DNA hypermethylation during cancer development. Oncogene (2001) 20, 24 - 33.

Agar↗

A novel Fc receptor for IgA and IgM is expressed on both hematopoietic and non-hematopoietic tissues.

By contrast to well-defined Fc gamma and Fc epsilon receptors, the structural and functional characteristics of Fc mu receptor are unclear. We have recently described a novel mouse Fc receptor, designated Fc alpha/mu receptor, and its human homologue, which bind both IgM and IgA. Here we show that the Fc alpha/mu receptor is expressed on mature, but not immature, B lymphocytes and acquires the ability to bind IgM and IgA antibodies after stimulation of B lymphocytes. Moreover, stimulation with phorbol 12-myristate 13-acetate increased endocytosis of IgM-coated microparticles mediated by the Fc alpha/mu receptor expressed on pro-B cell line Ba/F3 cells. We also show that the Fc alpha/mu receptor is expressed in secondary lymphoid organs, such as lymph node and appendix, kidney and intestine, suggesting an important role of the receptor for immunity in these organs.

Animals↗

Identification of a phosphoprotein that is downregulated in immortalized human fibroblasts.

Many lines of evidence indicate that the immortalization step is critical for the neoplastic transformation of normal human cells. Once normal human cells have been immortalized, they are relatively easily transformed into neoplastic cells. In order to understand these phenomena, patterns of protein phosphorylation in proliferating normal human fibroblast cell strains and their immortalized cell lines were compared by using two-dimensional polyacrylamide gel electrophoresis. It was found that the expression and phosphorylation levels of the human heat shock protein 27 (HSP27) were predominantly downregulated in the immortalized cells compared with those in their normal counterparts. In the normal cells, HSP27 expression and phosphorylation were markedly increased by physiological and nonphysiological stresses, such as serum addition, treatment with a carcinogenic agent like 4-nitroquinoline-1-oxide, and a high osmotic pressure. This may be a normal defense against acute changes of cellular environment and cytotoxic effects. However, these stresses had no effects on the expression and phosphorylation of HSP27 in the immortalized cells. These results suggest that an abnormal regulation of HSP27 expression and phosphorylation may be one of the reasons for easy neoplastic transformation of the immortalized cells by the treatment with carcinogenic agents.

Amino Acid Sequence↗

Reoperative coronary artery bypass grafting using a minimally invasive direct coronary artery bypass procedure.

OBJECTIVE: Reoperative coronary artery bypass grafting with cardiopulmonary bypass tends to cause a higher mortality and morbidity than the primary operation. The purpose of this study was to discuss the effectiveness and safety of a minimally invasive coronary artery bypass procedure for patients who had previously undergone coronary artery bypass surgery. METHODS: We performed redo single coronary artery bypass grafting to the left anterior descending coronary artery in 9 patients and to the right coronary artery in 3 patients using minimally invasive cardiac surgery. The graft to the left anterior descending coronary artery was taken from the left internal thoracic artery in 5 patients, the right gastroepiploic artery in 3 patients, and from the saphenous vein in the other 1 patient. The graft to the right coronary artery was from the right gastroepiploic artery in all 3 patients. RESULTS: All grafts were patent. There was no major postoperative complication and no surgical or hospital death except one late death. CONCLUSIONS: In selected patients, we could safely and completely perform coronary artery bypass re-grafting to the left descending coronary artery or right coronary artery using a minimally invasive operation.

Aged↗

Oral glucocorticoid-induced fall in cortical bone volume and density in postmenopausal asthmatic patients.

Despite a deepening understanding of the influence of glucocorticoids (GC) on trabecular bone, little is known about GC-induced cortical bone loss. To elucidate the mechanism of GC-induced loss of cortical bone strength with particular reference to cortical bone loss, changes in cortical density, relative cortical volume, and the Strength Strain Index (SSI) based on biomechanical analyses of the geographic distribution of cortical bone material were measured. These parameters were compared, using peripheral quantitative computed tomography (pQCT), among the following age-matched groups: 68 postmenopausal asthmatic patients receiving high-dose oral GC in addition to inhaled GC (oral GC group), 68 postmenopausal asthmatic patients receiving only inhaled GC (inhaled GC group) and 69 postmenopausal controls without asthma or GC therapy (control group). Cortical bone mineral density (BMD) was measured, relative cortical volume was obtained by dividing the cortical area by the total bone area using pQCT (Stratec XCT960), and the Strength Strain Index (SSI) was calculated in the radius based on the density distribution around the axis. Spinal fracture was assessed on lateral radiographs. The number of vertebral fractures per patient correlated highly with cortical BMD, relative cortical volume and SSI values at the radius. The number of vertebral fractures per patient and the number of patients with fracture were similar between the control and inhaled GC group, both being significantly lower than those in the oral GC group. Total BMD, trabecular BMD, cortical BMD, relative cortical volume and SSI were similar between the first two, being significantly higher than in the last group. The slopes of cortical volume-density relationship, however, were identical among the three groups, indicating the persistence of cortical bone remodeling and a similar degree of calcification regardless of GC administration.

Administration, Inhalation↗

Further insight into the task-dependent excitability of motor evoked potentials in first dorsal interosseous muscle in humans.

We have reexamined the contradictory evidence in which task-dependent excitation of motor evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle was stronger with increasingly more complex finger tasks than with individual finger movement tasks. In the first step of the experiment, based on previous findings, we investigated remarkable functional differences between intrinsic and extrinsic hand muscles during complex finger tasks (precision and power grip). During the performance of the tasks, the optimal stimulus intensity of the transcranial magnetic stimulation (TMS) was applied to the contralateral motor cortex. MEPs of the FDI, extensor carpi radialis (ECR), and flexor carpi radialis (FCR) muscles were recorded simultaneously with increased background EMG activity step by step in both tasks. The intensity threshold of TMS was lower in the precision grip. Furthermore, the MEP amplitudes of FDI muscle dependent on the background EMG activity were different between these two tasks, i.e., MEP amplitudes and regression coefficients in a precision grip were larger than those in a power grip. Although our results for MEP amplitude and threshold in the FDI muscle were similar to previous reported evidence, the different contributions of a synergistic muscle (in particular, the ECR muscle) during performance in these tasks was new evidence. Since there were no differences in cutaneous afferent effects on both tasks, corticomotoneuronal (CM) cells connected to FDI motoneurons seemed generally to be more active during precision than power gripping, and there were different contributions from synergistic muscles during the performance of these tasks. In the second part of the experiment, the results obtained from the complex tasks were compared with those from a simple task (isolated index finger flexion). MEP amplitudes, dependent on the background EMG activity during isolated index finger flexion, varied among subjects, i.e., the relationship between the MEP amplitude and the background EMG of the FDI muscle showed individual, strategy-dependent modulation. There were several kinds of individual motor strategies for performing the isolated finger movement. The present results may explain the previous contradictory evidence related to the contribution of the CM system during coordinated finger movement.

Adult↗