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Biomedical subjects

N Matsuo

Publications and source records attributed to N Matsuo.

At least 109 records · Page 6Linked to original sources
PubMed1998

Effect of synthetase inhibitors and receptor antagonists in antigen-induced contraction of human lung parenchyma.

BACKGROUND: Chemical mediators induce bronchoconstriction, enhance vascular permeability, and promote inflammation. The use of synthetase inhibitors and receptor antagonists of these mediators may be useful in the treatment of asthma. OBJECTIVES: We evaluated the role of chemical mediators in mite antigen-induced contraction in resected human lung parenchyma using synthetase inhibitors and receptor antagonists for these mediators. METHODS: Resected human lung parenchymal specimens were passively sensitized with serum obtained from patients with asthma showing an IgE RAST score for mites > or = 5. The specimens were suspended in Magnus bath filled with buffer. After confirmation of contraction using PGF2 alpha, buffer or synthetase inhibitors or receptor antagonists of various chemical mediators were added. Contraction of parenchyma was induced by the addition of mite antigen, and the concentration of thromboxaneB2 (TXB2), leukotriene (LT), and histamine was measured before and after contraction. RESULTS: Thromboxane A2 (TXA2) synthetase inhibitors significantly inhibited TXB2 release but not contraction. Leukotriene synthetase inhibitors significantly inhibited both LT release and contraction. The magnitude of the inhibitory effect was in the order of LT receptor antagonist > 5-lipoxygenase inhibitor > TXA2 receptor antagonist > PAF antagonist, TXA2 synthetase inhibitor, antihistamine > cyclooxygenase inhibitor. CONCLUSION: Among chemical mediators, LT appears to be the most closely involved in the immediate antigen-induced contractile response in resected human lung parenchyma. Receptor antagonists produced a more marked inhibition of antigen-induced contraction than synthetase inhibitors.

Aged↗
PubMed1998

Comparison of three treatment regimens of inhaled sodium cromoglycate in the management of adult patients with severe, steroid-dependent asthma.

BACKGROUND: Asthmatic patients whose asthma remains poorly controlled despite treatment with high doses of inhaled corticosteroids and co-administration of oral corticosteroids are a difficult problem in therapeutics. OBJECTIVE: To investigate the relative efficacy of three treatment regimens of inhaled sodium cromoglycate in the treatment of adult, severe, corticosteroid-dependent patients as determined by the reduction in the dose of oral corticosteroids and change in lung function. METHODS: Open, randomized, group comparative trial of 12 weeks duration in asthmatic patients attending a hospital outpatient department. Patients whose asthma is (1) severe according to the classification of the Japanese Society of Allergology, (2) stable, and (3) needing treatment with at least 1600 microg of inhaled beclomethasone dipropionate and 5 mg or greater of oral prednisolone per day. The three treatment regimens of inhaled sodium cromoglycate were group A received sodium cromoglycate powder at a dose of 16 mg/day administered by a metered dose inhaler. Group N received sodium cromoglycate aqueous solution at a dose of 80 mg/day administered by a nebulizer. Group C received sodium cromoglycate aqueous solution (80 mg/day) combined with salbutamol (3 mg/day) administered by a nebulizer. The main outcome measures were a change in the daily dose of oral corticosteroids and in lung function with twice daily measurements of peak expiratory flow (PEF) recorded in the morning (PEF AM) and in the evening (PEF PM). RESULTS: Mean reduction in oral corticosteroid dose/day was group A, 3.68 mg (95% CI 1.35,5.95); group N, 3.59 mg (95% CI 0.73,6.45); and group C, 3.97 mg (95% CI 1.81,6.13). The dosage reductions are all significant but with no differences between the groups. The mean increase in PEF over the last 4 weeks of treatment compared with baseline values was significant in all groups. The increases in group C are significantly greater than those in the other groups. These changes are all significant and the increases in group C are significantly greater than those in the other groups. CONCLUSIONS: Inhaled sodium cromoglycate may be a useful additional treatment in the management of adult patients with severe, oral steroid-dependent asthma. Of the three methods of administration compared in this trial the most useful immediate results were obtained when the drug was administered as an aqueous solution mixed with salbutamol and delivered by a powered nebulizer.

Administration, Inhalation↗
PubMed1998

Schwartz-Matsuo syndrome in retinal detachment with tears of the nonpigmented epithelium of the ciliary body.

PURPOSE: To elucidate clinical features of Schwartz-Matsuo syndrome (photoreceptor outer segment glaucoma) occurring in retinal detachment with tears of the nonpigmented epithelium of the pars plana or plicata of the ciliary body. METHODS: We reviewed retrospectively medical records of 17 consecutive patients (18 eyes) with retinal detachment caused by tears of the nonpigmented epithelium of pars plana (10 eyes) and pars plicata (8 eyes) of the ciliary body. RESULTS: Aqueous cells, ranging from 1+ to 3+, were found in 15 eyes, in contrast with no cells in the other 3 eyes. Eleven of the 15 eyes with aqueous cells showed circadian fluctuation of the intraocular pressure with a range, 4 mmHg or wider compared with the range in the fellow eye, but only 4 of these 11 eyes had a maximum pressure of 21 mmHg or higher. Photoreceptor outer segments were detected in the aqueous humor of 8 eyes out of 14 eyes with aqueous cells in which aqueous tap was done. The remaining 6 eyes had too small a number of aqueous cells for electron microscopy. CONCLUSION: Marked fluctuation of the intraocular pressure compared with the fellow eye, which was not necessarily associated with its rise, was found in retinal detachment with tears of the nonpigmented epithelium of the ciliary body, and should be included as one of key features for diagnosis of Schwartz-Matsuo syndrome.

Adolescent↗
PubMed1998

Contribution of human hepatic cytochrome P450 isoforms to regioselective hydroxylation of steroid hormones.

1. Hydroxylation activities toward steroid hormones were determined for eleven forms of human hepatic cytochrome P450s expressed in yeast Saccharomyces cerevisiae cells. Microsomes were prepared from the yeast cells and assayed for their regioselectivity of hydroxylation toward progesterone, pregnenolone, dehydroepiandrosterone (DHEA) and oestrone. 2. 6 beta-Hydroxylation of progesterone was catalysed most efficiently by CYP3A4, followed by CYP2D6. CYP3A4 showed the highest progesterone 16 alpha-hydroxylation activity, followed by CYP1A1 and CYP2D6. 16 alpha-Hydroxylation of pregnenolone was catalysed efficiently by CYP1A1 and CYP3A4. Only CYP3A4 exhibited 16 alpha-hydroxylase activities toward DHEA and oestrone. 3. Addition of nifedipine, a typical substrate of CYP3A4, inhibited the 6 beta- and 16 alpha-hydroxylation of progesterone by CYP3A4. 4. These results suggest that CYP3A4 and CYP1A1 are responsible for the hydroxylation of these endogenous steroids, as well as xenobiotics, in human liver.

Aryl Hydrocarbon Hydroxylases↗
PubMed1998

Two types of initial ocular manifestations in intraocular-central nervous system lymphoma.

PURPOSE: To study initial ocular manifestations of ocular-central nervous system (CNS) lymphoma. METHODS: The authors reviewed medical records of 10 consecutive patients with intraocular-CNS lymphoma seen at Okayama University Hospital during 16 years from 1981 to 1996. RESULTS: Three patients showed only vitreous opacity as an initial sign, whereas five other patients had typical yellowish-white infiltrates at the sub-retinal pigment epithelial (sub-RPE) level without vitreous opacity. Both manifestations were found in two patients. In seven patients, ocular symptoms developed first, followed by brain lesions. In contrast, in three patients the initial presentation was brain tumor, for which they received chemotherapy; subsequently, vitreous opacity without sub-RPE infiltrates developed. The diagnosis was made by vitrectomy in four patients, three of whom had also undergone brain biopsy; by aqueous tap in one; and by brain biopsy in one. The other four patients were diagnosed clinically, and one of them was confirmed later to have lymphoma by autopsy. CONCLUSIONS: The initial ocular manifestations of intraocular-CNS lymphoma were of two types, sub-RPE infiltrates and vitreous opacity. Keeping these two manifestations in mind will help physicians consider a diagnosis of intraocular-CNS lymphoma earlier.

Adult↗
PubMed1998

Transplanted and repopulated retinal pigment epithelial cells on damaged Bruch's membrane in rabbits.

AIMS: The authors studied how artificially damaged Bruch's membrane influenced growth and differentiation of transplanted embryonic retinal pigment epithelial (RPE) cells and of host RPE cells in rabbits. METHODS: Embryonic RPE cells obtained from pigmented rabbits were transplanted into the subretinal space of adult albino rabbits. The host RPE was removed with a silicone cannula, and Bruch's membrane was damaged by scratching with a microhooked 27 gauge needle under the detached retina in closed vitrectomy. The transplantation sites were examined 3, 7, and 14 days after surgery by light and electron microscopy. RESULTS: Varying degrees of damage in Bruch's membrane were observed. Pigmented and hypopigmented RPE cells showed a normal polarity and tight junctions were seen at the sites of mild to moderate damage 3-7 days after the surgery. In contrast, fibroblast-like cells with no such features of RPE cells formed multiple layers at the sites of severe damage involving the full thickness of Bruch's membrane and the choriocapillaris even 14 days after the surgery. Without transplantation, host RPE cells repopulated the damaged areas in the same way as transplanted RPE cells. CONCLUSIONS: Transplanted embryonic RPE cells as well as host RPE cells grew and differentiated on the moderately damaged Bruch's membrane, while the severely damaged Bruch's membrane did not allow differentiation of RPE cells although these cells could grow and cover the damaged areas.

Animals↗
PubMed1998

Hypergonadotropic hypogonadism in a 3-year-old girl with blepharophimosis, ptosis, and epicanthus inversus syndrome.

We report on ovarian dysfunction in a 3-year-old girl with blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES). A gonadotropin releasing hormone test showed hyperresponses of luteinizing hormone (<0.2-->7.2 mIU/ml) and follicle-stimulating hormone (7.1-->44.8 mIU/ml), and a human menopause gonadotropin test yielded no estradiol response (13-->11 pg/ml). The results suggest that primary ovarian failure in type I BPES can take place in early childhood.

Blepharophimosis↗
PubMed1998

Progressive subretinal fibrosis in patients with rheumatoid arthritis and renal dysfunction.

We present two patients (56-year-old and 71-year-old women) who developed subretinal fibrosis in parallel with exacerbation of rheumatoid arthritis and deteriorated renal function. The first patient developed subretinal fibrosis in the right eye, coupled with multifocal choroiditis and serous retinal detachment in both eyes, in the course of rapidly progressive glomerulonephritis complicated with rheumatoid arthritis. Antineutrophil cytoplasmic antibody was positive in a perinuclear pattern (pANCA) and the increased dose of prednisolone to 40 mg/day resulted in subsidence of the subretinal inflammation. The second patient developed subretinal fibrosis in the left eye with mottled retinal pigment epithelium of both eyes, in the course of rheumatoid arthritis and stable chronic renal failure. Although the manifestations of subretinal fibrosis and concurrent renal dysfunction were different between these two patients, subretinal fibrosis might be noted as a complication of rheumatoid arthritis and renal dysfunction.

Aged↗
PubMed1998

Substrate specificity of the alpha-L-arabinofuranosidase from Trichoderma reesei.

The precise substrate specificities of an alpha-L-arabinofuranosidase from Trichoderma reesei were investigated. The enzyme released arabinose at appreciable rates from p-nitrophenyl-alpha-L-arabinofuranoside, O-alpha-L-arabinofuranosyl-(1-->3)-O-beta-D-xylopyranosyl-(1-->4) -D-xylopyranose (A1X2), arabinan, arabinoxylan, arabinogalactan, debranched-arabinan and gum arabic, but not from O-beta-D-xylopyranosyl-(1-->4)-[O-alpha-L-arabinofuranosyl-(1-->3)] -O-beta-D-xylopyranosyl-(1-->4)-D-xylopyranose (A1X3) or O-beta-D-xylopyranosyl-(1-->2)-O-alpha-L-arabinofuranosyl -(1-->3)-O-beta-D-xylopyranosyl-(1-->4)-O-beta-D-xylopyranosyl-(-->4) -D-xylopyranose (A1X4). The enzyme hydrolyzed methyl 2-O-, methyl 3-O- and methyl 5-O-alpha-L-arabinofuranosyl-alpha-L-arabinofuranosides to arabinose and methyl alpha-L-arabinofuranoside with the order of hydrolysis being: (1-->5)- > (1-->2)- > or = (1-->3)-linkages. The enzyme hydrolyzed the (1-->3)-linkage faster than the (1-->5)-linkage of methyl 3,5-di-O-alpha-L-arabinofuranosyl-alpha-L-arabinofuranoside. The degree of conversion of arabinan and debranched-arabinan to monosaccharides by the enzyme was 33.0% and 9.1%, respectively. The alpha-L-arabinofuranosidase preferentially cleaved the arabinosyl side-chain from the arabinan rather than the terminal arabinosyl residue of the arabinan backbone.

Carbohydrate Conformation↗
PubMed1998

Effects of cysteinyl-leukotriene receptor antagonist, thromboxane A2 receptor antagonist, and thromboxane A2 synthetase inhibitor on antigen-induced bronchoconstriction in patients with asthma.

BACKGROUND: Leukotriene (LT) and thromboxane A2 (TXA2) receptor antagonists have been used in the treatment of asthma. OBJECTIVES: We examined the effects of an LT receptor antagonist, TXA2 receptor antagonist, and TXA2 synthetase inhibitor on bronchoprovocation test (BPT) in patients with mild-to-moderate atopic asthma. METHODS: BPT was performed four times in each of six asthmatics. Development of the immediate asthmatic reaction (IAR) and late asthmatic reaction (LAR) was confirmed on the first BPT (BPT1). After a 7-day washout period, an LT receptor antagonist (pranlukast, 450 mg/d), TXA2 receptor antagonist (seratrodast, 80 mg/d), or TXA2 synthetase inhibitor (ozagrel, 800 mg/d) was administered orally over 7 days at random using a cross-over method (BPT2-4). Blood levels of LTB4, LTC4, LTD4, 11-dehydrothromboxane B2, eosinophil cationic protein, and histamine were measured at reaction phases of pre-BPT, IAR, and LAR. RESULTS: Administration of pranlukast suppressed IAR by 80.5% (p < 0.0001) and LAR by 54.6% (p = 0.0391). Ozagrel significantly suppressed IAR by 39.5% (p = 0.0413), but the fall in FEV1 was >20% (21.56+/-4.173%). Seratrodast did not suppress IAR or LAR. Blood levels of chemical mediators did not correlate with the suppressive effects of the tested drugs. CONCLUSIONS: The LT receptor antagonist was considered to be the most effective. LT might play a more important role in the pathogenesis of asthma than TXA2. Our data showed that measurement of blood levels of chemical mediators is not useful in identifying the pathogenic mechanisms of asthma.

Administration, Oral↗
PubMed1998

Timing for discontinuation of treatment with a long-acting gonadotropin-releasing hormone analog in girls with central precocious puberty. TAP-144SR CPP Study Group.

The optimal timing for discontinuing treatment with a long-acting gonadotropin-releasing hormone (GnRH) analog (TAP-144SR) was investigated in patients with central precocious puberty (CPP). Thirty-five girls with CPP (21 with idiopathic disease and 14 with organic disease) were treated with the analog for 3 to 5 years. No significant differences were seen between the idiopathic and the organic CPP in the suppressive effect of bone maturation. Advancement of bone maturation was noticeably suppressed during the period between bone ages (BA) of 11.0 and 11.9. The height standard deviation score (Ht-SDS) for BA was consistently improved from 10 to 11.5 years of BA, and patients reached peak Ht-SDS at a BA of 11.5 years. The deltaHt-SDS (annual change in Ht-SDS) was noticeably decreased at BA over 12 years in spite of prolongation of the treatment. In the eight patients who have reached final height, the average Ht-SDS was -0.49 at end of the treatment (BA 11.7 years) and the final Ht-SDS was - 1.1 SD, respectively. Predicted adult height at the end of the treatment was significantly higher than the actual final height (P<0.01). The results suggest that a fall in Ht-SDS for BA which usually occurs at approximately 12 years of BA, is an indication for cessation of the treatment with TAP-144SR, and residual growth potential judged solely from BA may be decreased in girls with CPP after discontinuation of the treatment.

Age Determination by Skeleton↗
PubMed1998

Transdifferentiation of chick embryonic retinal pigment epithelial cells to lentoid structure in suspension culture.

To test transdifferentiation of retinal pigment epithelial (RPE) cells in suspension culture, chick embryonic RPE sheets and dissociated RPE cells were cultured for two months in a non-adherent dish for suspension culture. RPE cells, isolated as a sheet, aggregated immediately and remained the same size with their differentiated characteristics for two months. The presence of basic fibroblast growth factor (bFGF) at concentrations of 10 ng/ml or higher induced the formation of a spherical lentoid structure which was positive for crystallin and bFGF receptor. In contrast, dissociated RPE cells did reaggregate but did not develop the lentoid structure even in the presence of bFGF. The transdifferentiation of RPE cells to the lentoid structure in this study was in contrast to their transdifferentiation to the retina, as reported in a previous study.

Animals↗
PubMed1998

[Treatment of hepatocellular carcinoma by segmental SMANCS Lipiodol-TAE].

Segmental SMANCS Lipiodol TAE (Seg. SMANCS Lp-TAE) using SMANCS was used to treat HCC in 58 patients and was evaluated in comparison with Seg. Lp-TAE using Epirubicin performed in 50 patients with respect to the course of atrophy of the embolized area, recurrence rate and side effects. On serial CT (Lp-CT) performed after TAE, in cases with P type in which the tumor is present in the periphery of the embolized area and showing Type I homogeneous accumulation of Lp within the tumor, the incidence of atrophy in the embolized area including the tumor was high and the recurrence rate was low. Although no significant difference in the recurrence rate was noted between the groups in which SMANCS and EPI were used, there were more cases with marked atrophy and a lower recurrence rate in the former. No difference was found in post-procedural side effects such as fever between the two groups, while hypotension was rarely observed during the procedure in the group in which SMANCS was used and was easily managed with intravenous steroids. The present results suggest that Seg. SMANCS Lp-TAE is an effective local treatment for HCC limited to a subsegment or segment.

Aged↗
PubMed1997

Eicosanoids mediate induction of immune genes in the fat body of the silkworm, Bombyx mori.

The expression of cecropin and lysozyme genes is induced in response to bacterial peptidoglycan in the fat body of the silkworm, Bombyx mori. Specific inhibitors of either phospholipase A2, cyclooxygenase or lipoxygenase significantly inhibit the induction of the immune genes both in vivo and in cultured fat body as detected by means of Northern hybridization. Arachidonic acid injected into the larvae induces the expression of the cecropin and lysozyme genes. The findings support the idea that eicosanoids mediate some process leading to the expression of immune genes in the fat body following recognition of peptidoglycan as a signal for invading bacteria.

Animals↗
PubMed1997

Cloning of a cDNA encoding a novel sugar transporter expressed in the neonatal mouse hippocampus.

While analyzing active genes in the neonatal mouse hippocampus, we observed several novel genes that were abundantly expressed in this tissue. We report here cloning and sequencing of one of these transcripts, HiAT1 (Hippocampus Abundant Gene Transcript 1). The mRNA was 2.7 Kb in length, and the deduced amino acid sequence consisted of 490 amino acids with characteristics typical of members of the sugar transporter family. However, its overall sequence homology to known transporter cDNAs was only about 30%, suggesting strongly that it represents a novel sugar transporter gene. Northern hybridization analyses showed this transcript is detected in adult and embryonic brains, as well as in other tissues.

Amino Acid Sequence↗
PubMed1997

Cloning of a putative vesicle transport-related protein, RA410, from cultured rat astrocytes and its expression in ischemic rat brain.

To elucidate the role of astrocytes in the stress response of the central nervous system to ischemia, early gene expression was evaluated in cultured rat astrocytes subjected to hypoxia/reoxygenation. Using differential display, a novel putative vesicle transport-related factor (RA410) was cloned from reoxygenated astrocytes. Analysis of the deduced amino acid sequence showed RA410 to be composed of domains common to vesicle transport-related proteins of the Sec1/Unc18 family, including Sly1p and Sec1p (yeast), Rop (Drosophila), Unc18 (Caenorhabditis elegans), and Munc18 (mammalian), suggesting its possible role in vesicular transport. Northern analysis of normal rat tissues showed the highest expression of RA410 transcripts in testis. When astrocyte cultures were subjected to a period of hypoxia followed by reoxygenation, induction of RA410 mRNA was observed within 15 min of reoxygenation, reaching a maximum by 60 min. At the start of reoxygenation, the addition of diphenyl iodonium, an NADPH oxidase inhibitor, blocked in parallel astrocyte generation of reactive oxygen intermediates and expression of RA410 message. In contrast, cycloheximide did not affect RA410 mRNA levels, indicating that RA410 is an immediate-early gene in the setting of reoxygenation. Using polyclonal antibody raised against an RA410-derived synthetic peptide, Western blotting of lysates from reoxygenated astrocytes displayed an immunoreactive band of approximately 70 kDa, the expression of which followed induction of the mRNA. Fractionation of astrocyte lysates on sucrose gradients showed RA410 antigen to be predominantly in the plasma membrane. Immunoelectron microscopic analysis demonstrated RA410 in large vesicles associated with the Golgi, but not in the Golgi apparatus itself, consistent with its participation in post-Golgi transport. Consistent with these in vitro data, RA410 expression was observed in rat brain astrocytes following transient occlusion of the middle cerebral artery. These data provide insight into a new protein (RA410) that participates in the ischemia-related stress response in astrocytes.

Amino Acid Sequence↗