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T Matsuda

Publications and source records attributed to T Matsuda.

At least 271 records · Page 15Linked to original sources
PubMed1999

Spatial regulation and surface chemistry control of monocyte/macrophage adhesion and foreign body giant cell formation by photochemically micropatterned surfaces.

A long-standing goal of biomedical device development has been the generation of specific, desired host blood and tissue responses. An approach to meeting this design criteria is precise surface modification that creates micropatterns of distinct physicochemical character to direct cell adhesion and behavior. For this study, poly(ethylene terephthalate) films were coated with poly(benzyl N, N-diethyldithiocarbamate-co-styrene) and sequentially exposed to monomer solutions for photoirradiation. A photomask was placed over different regions to generate micropatterned surfaces with graft polymer stripes of three distinct ionic characters. Human monocytes were cultured on these surfaces to ascertain whether adhesion and fusion of monocytes/macrophages could be controlled. Nonionic polyacrylamide greatly inhibited adhesion and induced clumping of the few monocytes that did adhere. Macrophage adhesion and spreading led to high degrees of interleukin-13 induced foreign body giant cell formation on both the anionic poly(acrylic acid), sodium salt, and benzyl N,N-diethyldithiocarbamate portions of the culture surface. In spite of the highest observed levels of monocyte/macrophage adhesion on cationic poly(dimethylaminopropylacrylamide), methiodide, the adherent cells were not competent to undergo fusion to form foreign body giant cells. These results suggest that inflammatory cell responses may be spatially controlled in a manner that may be ultimately exploited to improve the biocompatibility of medical devices.

Acrylic Resins↗
PubMed1999

Involvement of mutations in the DPC4 promoter in endometrial carcinoma development.

To define the target of chromosome 18q loss of heterozygosity, which is prevalent in endometrial carcinomas, we made a deletion map from 64 tumors. Loss of heterozygosity on 18q was found in 20 tumors. Among these, 14 tumors carried deletions at the 18q21.1 region, where the DPC4 gene is located. DPC4 transcription was disturbed in all six of the tumors with deletions at 18q21.1 examined, which sharply contrasted with the positive transcription in 12 tumors that retained heterozygosity at the 18q21.1 region. However, in the 14 tumors with the 18q21.1 deletions, the remaining allele had the wild-type sequence of the DPC4 coding region instead of somatic mutations in the DPC4 coding region. We found a one- and two-base substitutions in the DPC4 promoter in two of the six tumors that showed disturbed DPC4 transcription. Chloramphenicol acetyltransferase assays clearly demonstrated that the mutant promoters had the potential to suppress or silence DPC4 transcription, implicating the DPC4 gene in endometrial carcinoma.

Alleles↗
PubMed1999

Clinical efficacy of applying four-field portals to paraaortic irradiation in the treatment of cervical carcinoma.

Paraaortic nodal irradiation (PAI) was thought to be useful in the treatment of cervical cancer, but its clinical application has been limited by a relatively high morbidity. To reduce this morbidity, we routinely applied the four-field technique in PAI. To clarify its efficacy, clinical data were retrospectively analyzed. Ninety-seven patients with cervical cancer, who received a minimum 40 Gy of paraaortic irradiation between 1976 and 1994, were enrolled in the analysis. The patients were prescribed PAI using four-field portals with 10 MV photons (mean 50.4 Gy, range 40-70 Gy). The 5-year cause-specific survival rate was 32.2%. As for sequelae determined using the French-Italian glossary, G1a/G2a of stomach and duodenum developed in 26.8/1.0%, G2b of small bowel in 3.1%, G1b of nonspecific abdominal symptoms and/or signs in 12.4%, and G2 of bone in 3.1%. The operative history group had a slightly larger incidence of gastrointestinal complications than those without operative history, but the difference was not statistically significant. Application of four-field portals in PAI was useful, with acceptably low toxicity and successful compliance for moderate-to-high dose irradiation. This suggests that PAI may greatly contribute to the improvement of the therapeutic outcome of cervical carcinoma.

Adult↗
PubMed1999

Keyhole method for high-speed human cardiac cine MR imaging.

Although electrocardiographic (ECG)-gated magnetic resonance (MR) imaging is widely used for cardiac imaging, it has several disadvantages, such as long imaging time, respiratory artifacts, and motion artifacts induced by arrhythmia. An MR image can be acquired within about 0.3 seconds by using a fast gradient-echo imaging method. When this method is continuously applied, only two to three images can be obtained during a single cardiac cycle. The goal of this study is to obtain cine MR images in a single cardiac cycle using fast gradient-echo imaging combined with the "keyhole" method. The optimal conditions for the keyhole method for cardiac cine imaging were obtained by computer simulation based on a simplified cardiac model. When the read-out direction was set parallel to the cardiac short axis, left ventricular motion was almost correctly reproduced by the keyhole method with acquisition time reduced to one-fourth. J. Magn. Reson. Imaging 1999;10:778-783.

Computer Simulation↗
PubMed1999

Selective expression of folate receptor beta and its possible role in methotrexate transport in synovial macrophages from patients with rheumatoid arthritis.

OBJECTIVE: To investigate the expression of folate receptors (FR) and reduced folate carrier (RFC) and determine their relevance to methotrexate (MTX) transport in synovial mononuclear cells (SMC) from patients with rheumatoid arthritis (RA). METHODS: Levels of FR and RFC messenger RNA (mRNA) were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) in SMC from RA patients and peripheral blood mononuclear cells from healthy donors. Expression of FR-beta mRNA and protein was determined by Northern blot and Western blot analyses in RA SMC and monocyte/macrophage-lineage cells. FR-beta expression and folic acid binding capacity on the cell surface were examined by flow cytometric analysis and 3H-folic acid binding analysis. Studies of the inhibition of 3H-MTX uptake in the presence of unlabeled folic acid were performed to investigate the uptake of MTX through FR in RA SMC. RESULTS: RT-PCR, Northern blot, and Western blot analyses showed that FR-beta mRNA and protein were expressed selectively in activated monocytes and CD14+ RA SMC. These cells exhibited folic acid binding capacity. Furthermore, the FR-beta protein was shown to have folic acid binding capacity. Uptake of 3H-MTX through RA SMC was significantly inhibited in the presence of unlabeled folic acid. CONCLUSION: These results demonstrate that FR-beta expression is selectively elevated in RA synovial macrophages and suggest that MTX is transported through FR-beta in RA synovial macrophages. The findings suggest that folate antagonists with higher affinity for FR-beta would be useful in the treatment of RA.

Arthritis, Rheumatoid↗
PubMed1999

Expression of the c-kit proto-oncogene in rat hepatic allografts during acute rejection.

The role of the c-kit proto-oncogene in organ allograft rejection is not known. We investigated the level of c-kit expression following allogeneic transplantation of ACI rat liver grafts into LEW recipients. We studied c-kit mRNA and protein expression in groups of transplant recipients receiving hepatic isografts, hepatic allografts, or hepatic allografts after donor-specific blood transfusion (DST). Pretransplantation DST significantly prolonged survival of hepatic allografts. Infiltrates expressing c-kit were observed in allografts to untreated rats but not in groups receiving isografts or allografts following DST. Northern analysis also demonstrated abundant c-kit mRNA transcripts in the untreated allograft group in contrast to the isograft and the DST-treated groups. In addition, significantly more transcripts for interleukin-12 (IL-12), which is synergistic with c-kit, were present in untreated than in DST-treated allograft groups. In contrast, transforming growth factor beta (TGF-beta), which inhibits c-kit synthesis, was expressed abundantly in hepatic allografts to DST-treated rats but not in allografts to untreated animals. Transcripts for IL-10, which inhibits IL-12 production, were significantly more plentiful in hepatic allografts following DST than in those without DST. The results suggest that c-kit proto-oncogene expression in infiltrating cells is associated with rat hepatic allograft rejection.

Animals↗
PubMed1999

Peroxynitrite formation during rat hepatic allograft rejection.

The role of nitric oxide (NO) on tissue injury of hepatic allografts during rejection remains controversial. We investigated inducible nitric oxide synthase (iNOS) expression and formation of peroxynitrite in ACI rat liver grafts implanted in recipients. Animals were divided into four experimental groups: group I, isografts; group II, untreated hepatic allografts; group III, allografts treated with FK506; and group IV, allografts pretreated with donor-specific blood transfusion (DST). Serum nitrite/nitrate, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) concentrations increased significantly in group II rats after transplantation but were significantly lower in groups I, III, and IV. The numbers of macrophages that reacted with an antimacrophage iNOS monoclonal antibody as well as iNOS messenger RNA (mRNA) levels in liver specimens were also much lower in groups I, III, and IV as compared with group II. Immunostaining and Western blot analysis showed prominent tissue nitrotyrosine expression in untreated hepatic allografts, but not in allografts treated with FK506 or donor-specific blood. These results suggest that one of the mechanisms by which production of NO results in injury in rat hepatic allografts may be because of its reaction with superoxide to form peroxynitrite.

Animals↗
PubMed1999

Functional morphology of the suprachiasmatic nucleus.

In mammals, the biological clock (circadian oscillator) is situated in the suprachiasmatic nucleus (SCN), a small bilaterally paired structure just above the optic chiasm. Circadian rhythms of sleep-wakefulness and hormone release disappear when the SCN is destroyed, and transplantation of fetal or neonatal SCN into an arrhythmic host restores rhythmicity. There are several kinds of peptide-synthesizing neurons in the SCN, with vasoactive intestinal peptide, arginine vasopressin, and somatostatine neurons being most prominent. Those peptides and their mRNA show diurnal rhythmicity and may or may not be affected by light stimuli. Major neuronal inputs from retinal ganglion cells as well as other inputs such as those from the lateral geniculate nucleus and raphe nucleus are very important for entrainment and shift of circadian rhythms. In this review, we describe morphological and functional interactions between neurons and glial elements and their development. We also consider the expression of immediate-early genes in the SCN after light stimulation during subjective night and their role in the mechanism of signal transduction. The reciprocal interaction between the SCN and melatonin, which is synthesized in the pineal body under the influence of polysynaptic inputs from the SCN, is also considered. Finally, morphological and functional characteristics of clock genes, particularly mPers, which are considered to promote circadian rhythm, are reviewed.

Animals↗
PubMed1999

Concomitant increase in neutrophil adhesion to inflammatory peritoneum and remote organs during peritonitis.

BACKGROUND: Neutrophils contribute to the host defense mechanism, but they can cause remote organ injury in peritonitis. The purpose of this study was to examine neutrophil adhesion to the peritoneum and remote organs simultaneously in peritonitis using a fluorescence microscopic method. STUDY DESIGN: Experiment 1: Sprague-Dawley rats (n = 16) were injected intraperitoneally (ip) with saline solution or 10(5), 10(7), or 10(9) Escherichia coli. Five hours after challenge, 1 x 10(6) fluorescein-labeled neutrophils were infused. Two minutes after neutrophil injection, five peritoneal samples (the greater omentum, mesentery, parietal peritoneum, colon, and ileum), both lungs, the liver, and the right kidney were harvested for counting of labeled neutrophils under epifluorescent microscopy. Lung myeloperoxidase (MPO) activity was also determined. Experiment 2: Rats (n = 23) were given 10(9) E. coli ip. Before challenge (0 h) or at 1, 5, or 10 h after challenge, labeled neutrophils were infused. Then, the labeled neutrophil numbers in organs and lung MPO activities were assessed as described for Experiment 1. Hemodynamic and arterial blood gas data were also obtained in another set of rats before and at 1, 5, 8 and 10 h after 10(9) E. coli ip challenge. RESULTS: Experiment 1: The labeled neutrophil numbers in the peritoneum, lungs, and kidney showed significant positive correlations with the injected bacterial numbers. Lung MPO also positively correlated with E. coli number and labeled neutrophil number in the lungs. Experiment 2: Labeled neutrophil numbers in the peritoneum and kidney peaked at 5 h. The pulmonary labeled neutrophil number rose, reaching a plateau at 5 h. No remarkable change was observed in the hepatic labeled neutrophil number. There was a positive correlation between lung MPO activity and pulmonary labeled neutrophil number. Hemodynamic and blood gas data reflected a hyperdynamic state. CONCLUSIONS: Concomitant dose-dependent increases in neutrophil adhesion in the peritoneum, lungs, and kidney were observed in this peritonitis model. Increased neutrophil adhesion was transient in the peritoneum and kidney but persistent in the lungs. Strategies modulating neutrophil adhesion in organs are anticipated to be useful for the treatment of peritonitis.

Animals↗
PubMed1999

Use of technetium-99m sestamibi ECG-gated single-photon emission tomography for the evaluation of left ventricular function following coronary artery bypass graft: comparison with three-dimensional magnetic resonance imaging.

In patients who had undergone cardiac surgery (coronary artery bypass graft) and whose hearts showed abnormal movement during the cardiac cycle, we studied the accuracy of functional assessment using ECG-gated single-photon emission tomography (SPET) and the automated software developed by Germano et al. by comparing the findings with magnetic resonance (MR) images acquired three-dimensionally. Sixteen patients who had undergone cardiac surgery underwent 99mTc-sestamibi gated SPET (MIBI-g-SPET) and MRI on the same day. Left ventricular end-diastolic and end-systolic volumes (EDV, ESV) and ejection fraction (LVEF) were measured using MIBI-g-SPET and the aforementioned algorithm. Regional wall thickening was assessed using a four-point scale on MIBI-g-SPET and cine MRI. There was a good correlation between MIBI-g-SPET and MRI in respect of EDV (r=0.89), ESV (r=0.93) and LVEF (r=0.89). A high degree of agreement was found between the wall thickening scores obtained by MIBI-g-SPET and MRI in total segments (kappa=0.62) and in septal segments (kappa=0.67). It is concluded that ECG-gated perfusion SPET can provide regional and global functional information, including absolute volumes, in patients following cardiac surgery.

Aged↗
PubMed1999

Impaired response of granulocyte-committed progenitor cells to stem cell factor and granulocyte colony-stimulating factor in human cyclic neutropenia.

Although cyclic neutropenia (CN) has been the subject of extensive studies due to its striking clinical picture, the abnormality of hematopoietic progenitor cells in patients with CN has been poorly defined. We studied the sensitivity of progenitor cells of a CN patient to colony-stimulating factors (CSF) including G-CSF, interleukin-3 (IL-3), and stem cell factor (SCF). Peripheral blood progenitor cells of the patient required a significantly higher dose of G-CSF to give rise to colonies than those of normal controls. While the presence of SCF enhanced the number of G-CSF-induced colonies regardless of the concentration of G-CSF in normal controls, this synergistic effect of SCF was limited to the high concentration of G-CSF in the patient, indicating that the abnormality in hematopoiesis in CN involved more immature progenitor cells responsive to SCF.

Adult↗
PubMed1999

Up-regulation of ICH-1L protein by thromboxane A2 antagonists enhances cisplatin-induced apoptosis in non-small-cell lung-cancer cell lines.

We evaluated the effect of thromboxane A2 (TXA2) blockade on cisplatin-induced apoptosis in non-small-cell lung cancer (NSCLC) cell lines. Cisplatin induced apoptosis in PC/9 and PC-9/CDDP in a dose-dependent manner. Treatment with specific TXA2 antagonist, calcium 5(Z)-1R,2S,3S,4S-7-[3-phenylsulfonylaminobicyclo[2,2,1]hept-2-yl]- 5-heptonoate hydrate (S-1452) and 5(Z-6-[(1R,2R,3R,4S)-3-(N-4-bromobenzenesulfonyl aminomethyl) bicyclo[2,2,1]heptane-2-yl]-hex-5-enoic acid (ONO-NT-126), enhanced the cisplatin-induced apoptosis in each cell line. Acetyl-L-aspartyl-glutamyl-valyl-aspart-1-aldehyde (Ac-DEVD-CHO) inhibited cisplatin-induced apoptosis and enhancement of the apoptosis by TXA2 blockade, but acetyl-L-tyrosyl-valyl-alanyl-aspart-1-aldehyde (Ac-YVAD-CHO) had no effect on the apoptosis. There was no difference in the interleukin-1beta-converting enzyme (ICE) protease protein expression in either cell line. Cysteine protease p32(CPP32) protein expression was lower in PC-9/CDDP but was not changed by S-1452, cisplatin, or cotreatment with cisplatin and S-1452. Ice and Ced-3 homolog (ICH-1L) expression was significantly lower in PC-9/CDDP and was up-regulated by S-1452 or ONO-NT-126. These data suggest that ICH-1L might play a critical role in cisplatin-induced apoptosis and that TXA2 blockade up-regulates ICH-1L protein expression. Overexpression of ICH-1L and treatment with cisplatin might result in an increase in apoptosis in NSCLC cell lines.

Apoptosis↗
PubMed1999

Gallbladder torsion: case report and review of 245 cases reported in the Japanese literature.

We report here a case of torsion of the gallbladder in a 73-year-old woman. The patient was admitted to our hospital with right hypochondralgia. Ultrasonography and computed tomography demonstrated a distended gallbladder, with a multilayered wall, which contained no stones. Since the symptoms did not respond to antibiotics, laparotomy was performed. The gallbladder was found to be twisted around its pedicle and to be gangrenous. Cholecystectomy was performed, and the patient had an uneventful postoperative course. We also reviewed 245 cases reported in the Japanese literature. The clinical features of gallbladder torsion, which include low frequency of fever and jaundice, poor response to antibiotic therapy, and acute onset of abdominal pain, may be helpful in the differential diagnosis from acute cholecystitis. Moreover, a highly suggestive sign of gallbladder torsion observed by ultrasonography or computed tomography is a markedly enlarged "floating" gallbladder with a continuous hypoechoic line indicating edematous change in the wall.

Abdomen, Acute↗
PubMed1999

Effects of hypothermia on c-fos and zif/268 gene expression following rat forebrain ischemia.

PURPOSE: To determine the effects of prophylactic mild hypothermia against transient forebrain ischemia, we examined the levels and localization of c-fos and zif/268 gene expression in the rat hippocampal formation at an early period during reperfusion. METHODS: For the histochemical evaluation, Wistar rats were divided into three groups: normothermia (37 degrees C) during ischemia (n = 5), hypothermia (34 degrees C) during ischemia (n = 5), and sham-operated controls (n = 5). The former two groups were subjected to 10-min forebrain ischemia using the bilateral carotid artery occlusion with arterial hypotension (35 mmHg) technique. After 60 min of reperfusion, the brains were removed and the in situ hybridization technique was used to detect c-fos and zif/268 mRNA expression. Additionally, to determine the histopathological changes of neuronal degeneration, animals were treated with hypothermia during ischemia (n = 4) and normothermia during ischemia (n = 4). They were allowed to survive for 7 days, and then the sections of hippocampal formation were examined by light microscopy. RESULTS: Transient ischemia increased c-fos and zif/268 mRNA signal densities from 1.8- to 6.1-fold compared with that in controls in the hippocampus. Mild hypothermia significantly inhibited the induction of c-fos and zif/268 (P < 0.01). In the CA1 subfield, hypothermia protected against delayed neuronal degeneration (P < 0.05), which was observed after normothermic ischemia. CONCLUSION: The induction of transcription factor-related immediate early genes (IEGs) was a sensitive marker of the cellular response to ischemia. Mild hypothermia uniformly inhibited the induction of IEGs in the hippocampus, but the mechanisms underlying the protective effect of hypothermia against neuronal degeneration cannot be explained only by the IEGs.

Journal Article↗
PubMed1999

Induction of antenatal periventricular leukomalacia by hemorrhagic hypotension in the chronically instrumented fetal sheep.

OBJECTIVES: Our purpose was to determine whether systemic hypotension induced by rapid withdrawal of fetal blood would induce periventricular leukomalacia in the brain of premature fetal sheep. STUDY DESIGN: At 113 days' gestation, systemic hypotension (mean blood pressure <30 mm Hg) was induced by withdrawing approximately 35% of the fetoplacental blood volume in the hemorrhage group (n = 6), whereas in the control group (n = 4) isovolemic exchange transfusion was carried out. Six days after the insult, fetal brains were removed and processed for histologic analysis. RESULTS: Five of the 6 fetuses in the hemorrhage group exhibited periventricular white-matter lesions, consisting of nodular coagulation necrosis or diffuse axonal swellings or both. No abnormal findings other than these lesions were detected in the fetal brains in either experimental group. CONCLUSION: Hemorrhagic hypotension antenatally induced brain lesions similar to those of periventricular leukomalacia, suggesting that it is an essential element in the pathogenesis of periventricular leukomalacia in premature fetuses.

Animals↗
PubMed1999

In vivo airway eosinophil accumulation does not enhance antigen- or propranolol-induced bronchoconstriction in guinea pigs.

BACKGROUND: Chronic airway eosinophil accumulation is characteristic of asthma. However, it remains unclear whether airway eosinophils enhance or reduce release of chemical mediators and/or action of the released mediators in the airways in vivo, because previous investigators have indicated that eosinophil-derived factors such as histaminase and arylsulfatase may alter the allergic reaction by metabolizing chemical mediators. Recently, we have developed a guinea pig model of propranolol-induced bronchoconstriction (PIB), which is mediated by lipid mediators such as thromboxane A2 (TxA2), cysteinyl leukotrienes (cLTs) and platelet activation factor (PAF). This study was conducted to explain the influence of airway eosinophil accumulation on antigen-induced bronchoconstriction and the following PIB, both of which are mediated by lipid mediators. METHODS: Guinea pigs were transnasally treated with 75 microg/kg of polymyxin-B or vehicle twice a week for a total of 3 weeks. Guinea pigs were anesthetized and treated with diphenhydramine hydrochloride, and then artificially ventilated 24 h after the last administration of polymyxin-B or vehicle followed by passive sensitization. Propranolol at a concentration of 10 mg/ml was inhaled 20 min after an aerosolized antigen challenge. RESULTS: The proportion of eosinophils in bronchoalveolar lavage fluid obtained 15 min after the propranolol inhalation was significantly increased in guinea pigs treated with polymyxin-B compared with the vehicle. The polymyxin-B treatment did not affect antigen-induced bronchoconstriction or the following PIB. CONCLUSIONS: We conclude that eosinophils accumulated in the airways by polymyxin-B does not affect release of chemical mediators induced by antigen or propranolol inhalation, or action of released mediators in vivo.

Administration, Inhalation↗