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Biomedical subjects

T Matsuda

Publications and source records attributed to T Matsuda.

At least 415 records · Page 23Linked to original sources
PubMed1998

Role of leukotriene B4 in bronchial hyperresponsiveness induced by interleukin-8.

Repeated intranasal administration of interleukin 8 (IL-8) induces bronchial hyperresponsiveness (BHR) accompanied by lower airway neutrophil accumulation (ANA) in guinea-pigs. Leukotriene B4 (LTB4) is a chemotactic factor for neutrophils. To elucidate whether LTB4 and neutrophil elastase are involved in the IL-8-induced BHR and ANA, the effects of a LTB4 antagonist (ONO-4057) and a neutrophil elastase inhibitor (ONO-5046) on the responses were examined. IL-8 (5 microg x kg[-1]) was administered intranasally to guinea-pigs twice weekly for 3 weeks. One day after the last administration, animals were anaesthetized and artificially ventilated through tracheal cannulae, and lateral pressure at the tracheal cannula (Pao) was measured as an overall index of airway responses to inhaled histamine. ONO-4057 (2 or 20 mg x kg[-1]) or ONO-5046 (30 or 300 mg x kg[-1]) was administered intraperitoneally 24 and 1 h before anaesthesia. ONO-4057, but not ONO-5046, significantly inhibited the IL8-induced BHR and ANA, assessed by bronchoalveolar lavage, in a dose-dependent manner. These findings suggest that interleukin 8 causes bronchial hyperresponsiveness and airway neutrophil accumulation in guinea-pigs in vivo. In part this appears to be due to release of leukotriene B4, whereas it may not be mediated by neutrophil elastase.

Animals↗
PubMed1998

Atopy in cough sensitivity to capsaicin and bronchial responsiveness in young females.

We have shown previously that female sex is a determinant of cough sensitivity to inhaled capsaicin, but the relationship between atopy and the cough sensitivity has not been examined. The capsaicin cough threshold, defined as the lowest concentration of capsaicin causing five or more coughs, nonspecific bronchial responsiveness, defined as the provocative concentration of methacholine causing a 20% fall in the forced expiratory volume in one second (PC20), total immunoglobulin E (IgE) and specific IgEs to eight common aeroallergens (house dust 1, 2 and 6, Dermatophagoides pteronyssinus and D. farinae, Japanese cedar, ragweed and orchard grass) in the serum were measured in 71 nonsmoking, healthy young women aged 20.6+/-0.1 yrs (mean+/-EM). A structured interviewer-led questionnaire on allergic diseases revealed that one and six subjects had mild current and past asthma, respectively. These seven subjects were excluded from the data analysis. PC20 was significantly lower in 42 subjects showing a positive specific IgE than in 22 subjects showing a negative specific IgE to any of the eight allergens (p<0.05), while the capsaicin cough threshold was not significantly different between the subgroups. PC20 was significantly lower in subjects with positive specific IgE to Dermatophagoides and house dust, but not to the three kinds of pollen examined. It was confirmed that atopy indicated by specific immunoglobulin E to mite-related antigens, but not to pollen antigens, is associated with nonspecific bronchial responsiveness, and it is suggested that atopy is not a determinant of airway cough sensitivity in healthy, nonasthmatic subjects.

Adult↗
PubMed1998

[Response of Na+/Ca2+ antiporter to ischemia and glial/neuronal death].

Brain ischemia produces morphologic and biochemical alterations in astrocytes. This mini-review summarizes astrocytic responses to brain ischemia including our studies on the neuronal and astrocytic Na(+)-Ca2+ exchanger (NCX). NCX is considered to cause Ca2+ efflux (forward mode) or Ca2+ influx (reverse mode), depending on the electrochemical gradient of Na+ across the plasma membranes and membrane potential. We demonstrated that NCX is present in cultured neurons and astrocytes and that there are differences in their properties and distribution ratio of the isoforms between neurons and astrocytes. We also found that Ca2+ depletion followed by reperfusion with Ca(2+)-containing medium caused cell death in cultured astrocytes (Ca2+ paradox-like injury), but not in neurons. The study, carried out by the use of a specific antisense oligomer, provides direct evidence that Ca2+ paradox-like injury is mediated by NCX in the reverse mode. The injury was attenuated by inhibitors of the Na(+)-Ca2+ exchanger, heat shock protein and the calcineurin inhibitor FK506. In a preliminary experiment, we found that brain ischemia decreases the mRNA level of NCX in the hippocampus. Further studies on activation and cell injury of astrocytes will contribute to development of new drugs that modulate the function of astrocytes.

Animals↗
PubMed1998

[Apoptosis of astroglial cells].

Astrocytes, the most abundant glial cell type in the brain, are considered to have physiological and pathological roles in neuronal activities. We found that reperfusion of cultured astrocytes after Ca2+ depletion causes delayed cell death and that the Na(+)-Ca2+ exchanger in the reverse mode is responsible for this Ca(2+)-mediated cell injury (Ca2+ paradox injury). The Ca2+ paradox injury of cultured astrocytes is considered to be an in vitro model of ischemia/reperfusion injury, since a similar paradoxical change in extracellular Ca2+ concentration is reported in ischemic brain tissue. Furthermore, we demonstrated that heat shock proteins, glutathione and calcineurin inhibitors protected astrocytes against Ca2+ paradox-induced cell toxicity. We also observed DNA fragmentation, a typical apoptotic ladder, 2-3 days after hydrogen peroxide exposure. In addition, laser microscopic observation showed that reperfusion after the exposure to hydrogen peroxide caused nuclear condensation of astrocytes. Hydrogen peroxide-induced cell injury and DNA fragmentation were attenuated by the NF-kappa B inhibitor ammonium pyrrolidinedithiocarbamate, 1,10-phenanthroline and a caspase 3 inhibitor. These findings suggest that astrocytes are one of the targets for ROS and the oxidative stress-induced delayed death of astrocytes is at least due to apoptosis.

Animals↗
PubMed1998

Clinicopathological studies on association of gallbladder carcinoma and pancreaticobiliary maljunction.

During the past 17 years, 1,722 of 4,832 consecutive patients investigated with endoscopic retrograde cholangiopancreatography (ERCP) were assessed by the radiological criteria of the Japanese Study Group of Pancreaticobiliary Maljunction (PBM). Out of these 1,722 patients, PBM was found in a total of 52, representing 3.0%, of which gallbladder carcinoma was associated with 14. These 14 with gallbladder carcinoma consisted of 10 (62.5%) of the 16 with PBM without association of congenital bile duct dilatation (CBDD) and 4 (11.1%) of the 36 PBM with CBDD. The relationship between PBM and gallbladder carcinoma was closely examined; PBM was noted in 14 (32.6%) of a total of 43 patients with gallbladder carcinoma compared to 38 (2.3%) among the 1,679 patients with various diseases excluding gallbladder carcinoma. Similarly, it was revealed that gallbladder carcinoma was predominantly noted in the 14 (26.5%) of the 52 patients with PBM in contrast to an incidence of 1.7% (29) among the 1,670 patients without PBM. As we studied the characteristic clinical features of the 14 gallbladder carcinoma patients with PBM when compared with 29 of those without PBM, the following was disclosed: on average, the patients with PBM were 10 years younger (49.4 vs 61.4 years in mean age); there was a preponderance of women (0/14 vs 12/17, male-female ratio); there existed a significantly lower incidence of associated gallstone disease (7.1% vs 72.4%). These figures were shown to be statistically significant. We concluded that the results prove a link between the crucial features of gallbladder carcinoma and PBM, and also suggest the promotive role of PBM in carcinogenesis of the gallbladder.

Adenocarcinoma↗
PubMed1998

Changes in the incidence and etiological patterns of bacteremia associated with acute leukemia over a 25-year period.

During the 25-year period from 1972-1996, 360 episodes of bacteremia occurred in 248 (45%) of a total of 548 patients with acute leukemia on our hematology ward, with the rate of occurrence remaining almost unchanged. Patients with acute nonlymphocytic leukemia, however, had a significant decrease in the incidence of bacteremia during the last 5-year period. Gram-negative bacilli decreased in relative frequency from 64% for the first 15-year period to 40% for the last 5-year period, whereas gram-positive cocci increased from 24% to 51%. Escherichia coli and Enterobacter cloacae somewhat decreased in frequency, whereas coagulase-negative staphylococci and streptococci had considerable increases. In contrast, Pseudomonas aeruginosa was isolated at a relatively constant frequency, forming one of the top two pathogens throughout the study period. Despite the shift toward gram-positive cocci, therefore, P. aeruginosa remains a key organism in considering the initial empiric antibiotic regimen and infection prevention during neutropenia.

Adolescent↗
PubMed1998

Chylothorax associated with inflammatory carcinoma.

We report a rare case of a woman with inflammatory carcinoma, an unusual type of cutaneous metastasis, arising from signet-ring cell carcinoma of the stomach, who developed chylothorax as the skin lesion progressed over the chest. No thoracoabdominal lymphadenopathy which can cause obstruction of the thoracic duct was shown by computed tomography. Although a very rare condition, inflammatory carcinoma could be a cause of non-traumatic chylothorax.

Adenocarcinoma↗
PubMed1998

Primary prostatic lymphoma of mucosa-associated lymphoid tissue.

We present a case of primary prostatic lymphoma referring to a 57-year-old man, who was admitted with the symptom of bladder outlet obstruction, and had a history of urination difficulty for two years. The symptoms and signs were compatible with a diagnosis of benign prostatic hypertrophy (BPH). The pathology of the specimen obtained from transurethral prostatectomy showed B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type. The patient has been asymptomatic and under complete remission after completion of chemotherapy consisting of doxorubicin, cyclophosphamide, vincristine and prednisone for 6 cycles.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

[Treatment-resistant dermatomycoses].

Dermatomycoses are a common category of fungal infections affecting the skin and subcutaneous tissues. Recent advances in topical and systemic antifungal chemotherapy have provided us with satisfactory results in most of the superficial fungal infections both clinically and mycologically. Despite the efficacy of antifungal agents, however, there are dermatomycoses that do not respond to our current standard regimens of treatment. Factors concerning the treatment-resistance, such as host's underlying conditions and fungal virulence, are discussed in detail.

Adult↗
PubMed1998

[Contingent negative variation (CNV) in the detection of deception task using a serial presentation of pictures].

The purpose of the experiment was to investigate the feasibility of using contingent negative variation (CNV) as an index of detection of deception. Twelve subjects were required to complete both an innocent and guilty condition in that order. In the innocent condition, a series of six pictures, two of which depicted different landscapes and four others which depicted different female faces, was presented repeatedly on a computer display. Subjects responded by pressing a button following the landscape picture (target stimulus) that was presented last in the sequence. In the guilty condition, the procedures were the same except that subjects were also required not to detect one of the female pictures in mind (critical item), which they had chosen after the completion of the innocent condition. As compared with the innocent condition, the CNV amplitudes decreased significantly immediately before the target stimulus in the guilty condition where subjects had to conceal the critical item. The implication of these data both for the psychological completion of the concealed task and the practice in the field were discussed.

Adult↗
PubMed1998

Decreased expression of cold-inducible RNA-binding protein (CIRP) in male germ cells at elevated temperature.

Physiological scrotal hypothermia is necessary for normal spermatogenesis and fertility in mammals. Cirp is a recently identified cold-inducible RNA-binding protein that is inducible at 32 degrees C in mouse somatic cells in vitro. Cirp is constitutively expressed in the testis of mouse and structurally highly similar to RBM1, a candidate for the human azoospermia factor. To elucidate the role played by Cirp in spermatogenesis, we investigated its expression levels during spermatogenesis and after heat stress. In the mouse testis, cirp mRNA was detected in the germ cells, and the level varied depending on the stage of differentiation. Also, a high level of Cirp protein was detected immunohistochemically in the nucleus of primary spermatocytes. Expression of Cirp was decreased in the GC-2spd(ts) mouse germ cell line when culture temperature was raised from 32 degrees C to 37 degrees C. When mouse testis was exposed to heat stress by experimental cryptorchidism or immersion of the lower abdomen in warm (42 degrees C) water, the expression of Cirp was decreased in the testis within 6 hours after either treatment. In human testis with varicocele analyzed immunohistochemically, germ cells expressed less Cirp protein than those in the testis without varicocele. These results demonstrated that CIRP expression is down-regulated at elevated temperature in male germ cells of mice and humans. Analysis of Cirp expression in the testes will help elucidate the molecular mechanisms leading to male infertility.

Adult↗
PubMed1998

Learning curve and conversion to open surgery in cases of laparoscopic adrenalectomy and nephrectomy.

PURPOSE: We examine how the level of experience acquired by the laparoscopist affects the outcome of laparoscopic adrenalectomy and nephrectomy, and what is necessary to avoid complications in these surgeries. MATERIALS AND METHODS: We retrospectively evaluated the experience levels of 8 urological laparoscopists between 1991 and 1995. In addition, other cases that were converted to open surgery were collected from the institutes with which the 8 laparoscopists were affiliated. RESULTS: The rates of conversion to open surgery were 6.4% in 204 cases of adrenalectomy and 14.3% in 63 of nephrectomy. Conversion rates were related to blood loss volume but not operative time. The major causes of conversion were bleeding in 45% of cases and adhesion in 34%. There were no mortalities. Mean operative time decreased significantly, reaching that of open surgery as the number of procedures increased up to 20 adrenalectomies and 10 nephrectomies. The volume of blood lost remained low from the early experience. Blood transfusion rates were 4.4% for adrenalectomy and 11.1% for nephrectomy. CONCLUSIONS: Operative time of these procedures decreased significantly with surgeon experience and reached that of open surgery. Cases in which adhesion is anticipated should be restricted to avoid conversion. These laparoscopic procedures are acceptable as a standard operative techniques for adrenal and renal diseases.

Adrenal Gland Diseases↗
PubMed1998

Seminal tract obstruction caused by childhood inguinal herniorrhaphy: results of microsurgical reanastomosis.

PURPOSE: Childhood inguinal herniorrhaphy is a frequent causes of seminal tract obstruction. We investigate the characteristics of this obstruction, surgical techniques for reanastomosis and outcomes in patients with bilateral or unilateral obstruction caused by inguinal herniorrhaphy in childhood. MATERIALS AND METHODS: We treated 22 men an average of 30.5 years old in whom average duration of obstruction was 27.1 years. Obstruction was bilateral in 9 patients and unilateral in 13, and 14 had azoospermia preoperatively. Microsurgical 2 layer vasovasostomy and/or specific tubule epididymovasostomy was performed. RESULTS: Inguinal and crossed vasovasostomy was done in 18 and 4 patients, respectively. The distal end of the vas was found at the internal inguinal ring or in the pelvic cavity in 57.1% of the vasa and more than 3 cm. of the vas had been resected in 37%. Sperm was noted in vasal fluid in 45.2% of the vasa during the operation and the patency rate of inguinal vasovasostomy was 88.9%. Ipsilateral epididymovasostomy performed after patent inguinal vasovasostomy in 5 patients with secondary epididymal obstruction resulted in normal sperm density and 3 pregnancies. In 7 men more than 2 procedures were done. There was sperm in the ejaculate in 12 of the 14 patients who had had azoospermia preoperatively and apparently increased sperm density postoperatively in 4 of the 8 who had not had azoospermia preoperatively. Pregnancy was achieved by 7 of the 21 married men (33.3%). CONCLUSIONS: Microsurgical reanastomosis of the seminal tract resulted in high patency and pregnancy rates in cases of seminal tract obstruction caused by childhood inguinal herniorrhaphy. Patients should elect seminal tract reanastomosis or assisted reproductive technology using epididymal or testicular sperm after receiving sufficient information on each treatment modality.

Adult↗
PubMed1998

[Detection of apolipoproteins E5 and E7 by a widely used commercial ApoE IFE kit--evidence provided by genotyping].

The purpose of this study is to examine a possibility to detect apolipoprotein (apo) E5 and E7 isoproteins with a commercial kit widely used (Phenotyping Apo E IFE System, Jokoh Co. LTD., Tokyo) and to clarify the frequency of the rare alleles in Central Japan. A total of 1,445 subjects living in Central Japan (1,030 hemodialysis patients and 415 apparently healthy individuals) was phenotyped for apo E isoproteins with the kit using isoelectric focusing with immunoblotting. In 23 subjects, unique apo E4 isoproteins, which migrate more basically than apo E4 isoprotein, were found. These unique isoproteins were proved to be apo E5 or E7 isoproteins by PCR with restriction fragment length polymorphism and with amplification refractory mutation systems, respectively. No significant differences in the frequencies of apo E5 or apo E7 alleles were observed between healthy individuals and hemodialysis patients (0.011 vs. 0.018, NS). The frequencies of apo E5 and E7 alleles were 0.001 and 0.005, respectively, in healthy individuals, and 0.003 and 0.005, respectively, in hemodialysis patients. These data in Central Japan were consistent with those in Western Japan (Matsunaga, et al, Clin Genet, 1995). These results indicate that the commercial kit is applicable to detect the rare alleles, apo E5 and E7 alleles and that the frequencies of the rare alleles in Central Japan are similar to those in Western Japan.

Adult↗
PubMed1998

Staphylococcus aureus causing chorioamnionitis and fetal death with intact membranes at term. A case report.

BACKGROUND: Neonatal infection without premature rupture of amniotic membranes occurs in 1-2% of births. The prevalence of membrane inflammation among term births is approximately 10%. There has been only one case report of Staphylococcus aureus as the cause of chorioamnionitis with intact membranes. CASE: A 24-year-old woman was admitted at 38 weeks of pregnancy with labor pains. On admission, she had a slight fever of 37.8 degrees C, but the other physical findings were within normal limits. There were no symptoms or signs of membrane rupture. Fetal heart monitoring showed slight tachycardia, 160 beats per minute, and loss of variability. Fetal death was detected when the fetal monitoring was resumed after being interrupted for 30 minutes. A male infant weighing 2,920 g was born dead. Artificial rupture of the membranes had been performed just before delivery. CONCLUSION: Culture specimens from the placenta and cord blood showed growth of S aureus, and histologic examination revealed chorioamnionitis. The bacteriologic evidence from the infant clearly identified S aureus.

Adult↗
PubMed1998

Increased plasma levels of free tissue factor pathway inhibitor in patients with Graves' disease.

Tissue factor pathway inhibitor (TFPI) is present in a free-form and in lipoprotein-associated forms in plasma. In this study, the plasma concentrations of total TFPI (tTFPI) and free-form TFPI (fTFPI) were measured in 25 patients with Graves' disease and 25 age-matched healthy subjects, and the relationship between thyroid state and plasma TFPI was examined. Plasma concentrations (median) of tTFPI and fTFPI in Graves' patients who were hyperthyroid were significantly increased compared with Graves' patients who were euthyroid (152 ng/ml versus 124 ng/ml, p < 0.01 and 41.3 ng/ml versus 20.2 ng/ml, p < 0.0001, respectively), and control subjects (152 ng/ml versus 96 ng/ml, p < 0.0001 and 41.3 ng/ml versus 18.7 ng/ml, p < 0.0001, respectively). There was no significant difference in plasma fTFPI concentrations between the euthyroid group and the control group. Plasma fTFPI concentrations correlated closely with thyroid hormone (T3) levels in the patients (r = 0.559, p < 0.005). Serial measurement of individual patients revealed that plasma concentrations of fTFPI and tTFPI were significantly decreased, reaching normal control values upon attainment of euthyroidism. In conclusion, the close correlation between plasma fTFPI and serum thyroid hormone levels suggests that thyroid hormones might influence the synthesis or metabolism of TFPI on the surface of endothelial cells in patients with Graves' disease. This is the first report concerning high concentrations of plasma tTFPI in patients with hyperthyroidism.

Adult↗
PubMed1998

[A case of systemic lupus erythematodes with hemosputum and pneumothorax probably resulting from pulmonary infarction and pulmonary angitis].

A 23-year-old man was admitted with fever, bloodysputum and consolidation in the bilateral lower lobes. Pulmonary infarction in the potla lower lobes was suspected because a lung perfusion scan showed a blood flow defect in the same places. Transbronchial biopsy was performed, and pulmonary hemorrhage and pulmonary angitis were demonstrated in the left lower lobe. His fever and bloodsyputum improved after steroid therapy, suggesting that pulmonary angitis may have been responsible for the bloodysputum. Subsequently pneumothorax occurred. In this case pulmonary infarction associated with pulmonary angitis may have been responsible for the pneumothorax.

Adult↗