Biomedical subjects

H Matsuda

Publications and source records attributed to H Matsuda.

At least 397 records · Page 22Linked to original sources

PubMed1999

Identification and immunohistochemical localization of annexin II in rat cornea.

PURPOSE: We have identified annexin II mRNA expression in the rat cornea and demonstrated immunolocalization of annexin II in normal and injured corneas. Furthermore, to investigate possible interaction between annexin II and its extracellular ligand tenascin during corneal wound healing, we also examined tenascin expression simultaneously. METHODS: Total RNA was extracted from the corneal tissue of male Wistar rats as well as from the cell cultures of corneal epithelial cells and keratocytes. cDNA was obtained by reverse transcription (RT). Annexin II mRNA expression was examined by polymerase chain reaction (PCR). Western blot analysis of annexin II protein was performed with protein samples that were obtained from the corneal tissue and cell cultures. In addition, the localization of annexin II and that of tenascin were clarified by immunohistochemical analysis, using both uninjured and epithelial scraped corneas. RESULTS: RT-PCR analysis revealed that annexin II mRNA was expressed in corneal tissues, epithelial cells and keratocytes. Western blot analysis of corneal epithelium and keratocytes showed a 38kDa band that corresponded to the molecular weight of annexin II. Immunohistochemical study showed that annexin II was present in keratocytes as well as the basal cells of corneal epithelium in the central cornea, and basal/suprabasal cells of the limbal epithelium. Positive annexin II immunoreactivity is translocated from cytoplasm to the cell periphery/extracellular position during the epithelial wound healing process. Annexin II and tenascin are coexpressed on the basal surface of limbal epithelium and the leading edge of the healing epithelium. The reappearance of cytoplasmic annexin II staining at the periphery of the cornea correlated with the epithelial cell proliferation. CONCLUSIONS: Annexin II is abundantly expressed in corneal tissue. The translocalization of annexin II protein suggests its role in the corneal epithelial migration during wound healing. The colocalization of annexin II and tenascin in migrating and proliferating corneal epithelial cells suggests that annexin II-tenascin interaction may play a role in epithelial wound healing.

Animals↗

PubMed1999

The suspected existence of Schistosoma mansoni in Dhanusha district, southern Nepal.

Eggs resembling those of Schistosoma mansoni have been observed in human stools collected from the inhabitants of Dhanusha district, in southern Nepal. In an attempt to determine if S. mansoni was present, 518 sera collected from subjects from four sites in this district were checked for antibodies to this parasite, in July 1996 and May 1997, using ELISA. Overall, 94 (18.1%) of the subjects were deemed seropositive, with the highest seroprevalence (42.7%) at the one site in Chisipani village and the lowest (1.0%) at one of the three sites in Tulaschichauda village. A follow-up study of Chisipani village, in January 1998, indicated a seroprevalence then of 22.7% (37/110). Although possible intermediate hosts, clinical manifestations and geographical distribution have yet to be explored, the present results indicate that S. mansoni probably does exist in the Dhanusha district of Nepal.

Animals↗

PubMed1999

Expression of a gene for cyclophilin which contains an amino-terminal endoplasmic reticulum-targeting signal.

We isolated a novel gene for cyclophilin (CyP) first identified as an intracellular target of the immunosuppressant cyclosporin A and also known to have peptidyl-prolyl cis-trans isomerase (PPIase) activity, named ATCYP5 from Arabidopsis thaliana. ATCYP5 encoded a polypeptide with 201 amino acids with a putative ER-targeting signal sequence at its N-terminal, but without the typical ER-retention signal in its C-terminal. In addition, ATCYP5 protein contained a seven amino-acid long sequence which has been found previously only in cytosolic CyPs from plants. The synthetic mutant green fluorescent protein (sGFP; S65T) was fused to the N-terminal part of ATCYP5, and expressed in tobacco BY-2 cells. The fluorescence derived from the fusion protein was detected mainly around the nucleus, indicating translocation into ER. ATCYP5 was expressed mainly in young stems especially in the apical region and weakly in leaves and roots.

Amino Acid Sequence↗

PubMed1999

Clinicopathological significance of poorly differentiated thyroid carcinoma.

The clinicopathological importance of a heterogeneous group of poorly differentiated thyroid carcinomas is not fully understood. Using data obtained from 303 surgically treated patients with differentiated thyroid carcinomas, the correlations between the aggressive histologic features and the clinicopathological findings, postoperative recurrences, and prognosis were retrospectively examined. In 201 cases, the carcinomas were well differentiated. The remaining 102 cases of poorly differentiated carcinomas were divided into two groups: focal-poorly differentiated (<10%) and diffuse-poorly differentiated (> or = 10%) carcinomas according to the extent of the poorly differentiated component. These poorly differentiated carcinomas were associated with high age (focal-poorly differentiated and diffuse-poorly differentiated versus well differentiated: 55 years and 59 versus 49; p < 0.0001), frequent presence of lymph node metastases (70% and 66% versus 48%; p = 0.0099) and distant metastases at diagnosis (11% and 11% versus 2%; p = 0.0098), and extrathyroidal invasion (53% and 53% versus 21%; p < 0.0001). There was independent correlation with age and the presence of extrathyroidal invasion. Cases of diffuse-poorly differentiated carcinomas showed frequent relapse (diffuse-poorly differentiated versus focal-poorly differentiated and well differentiated: 45% versus 30% and 24%; p = 0.0062) and poor prognoses (mean survival period = 9.15 versus 19.03 and 20.87 years; p < 0.0001) compared with the well and focal-poorly differentiated carcinomas. These data suggest that diffuse-poorly differentiated carcinoma is an important clinicopathological entity.

Adenocarcinoma, Follicular↗

PubMed1999

Vascular tone in patients with hemorrhagic shock.

BACKGROUND: In hemorrhagic shock, the alterations in arterial vascular tone, which are primarily regulated by adrenosympathetic influences are compensatory responses to bleeding. OBJECTIVE: The aim of this study was to evaluate vascular tone expressed by the volume elastic modulus (Ev) as a clinical monitor to detect the hypovolemic state. METHODS: Thirteen patients with hemorrhagic shock were studied. The initial Ev measurement was performed at arrival, and subsequent measurements were obtained 4 and 12 hours after arrival. Patients were divided into two groups by cluster analysis by using the Ev values at arrival and 4 hours after arrival. Circulatory parameters, the clinical course, and fluid were compared. RESULTS: The Ev values were identical at admission (cluster I vs. II: 456.4+/-197.1 vs 566.1+/-234.1 mm Hg, mean +/- SD). After 4 hours of fluid resuscitation, all patients were recovered from shock. In cluster I, the Ev remained high at 4 hours (523.4+/-75.1 mm Hg) and invasive treatments for hemostasis were required. In cluster II, the Ev significantly decreased at 4 hours (182.8+/-70.7 mm Hg, p < 0.01) and clinical courses were eventless thereafter. During 4 to 12 hours, more fluid was given in cluster I (p < 0.05). At 12 hours after arrival, the Ev values were identical in both clusters. CONCLUSION: These data demonstrate that the Ev increases in hemorrhagic shock. Furthermore, normotensive hypovolemic conditions generated by persistent bleeding can be detected by measuring the Ev.

Adolescent↗

PubMed1999

A chicken monoclonal antibody with specificity for the N-terminal of human prion protein.

Chickens were immunized with human prion protein (PrP) peptide H25 (amino acid residues 25-49) coupled to keyhole limpet hemocyanin. From a fusion experiment using the chicken fusion partner cell line MuH1 and immune spleen cells, one mAb, HUC2-13, was generated which reacted with the peptide. HUC2-13 was specific for a pentapeptide (RPKPG) of the N-terminal of the peptide H25. In Western blotting analysis, the mAb reacted with PrP materials from a human Creutzfeldt-Jakob disease (CJD) case and the membrane fraction from normal murine brain, but not with the same materials pretreated with proteinase K. When compared with the HUC2-13 and the conventional mouse mAb 3F4, the background stainings using the HUC2-13 were minimal. In immunohistochemistry, the HUC2-13 stained positively with kuru plaques in brain sections from patients with Gerstmann-Straussler syndrome (GSS), and also reacted with synaptic structures of the CJD patients. However, any immunolabelings using the HUC2-13 were not observed in the section from a patient with amyotrophic lateral sclerosis (ALS) as CJD-negative control. These results indicate that the mAb HUC2-13 is a suitable tool for immunological and diagnostic analyses of prion disease in humans and other mammals.

Amino Acid Sequence↗

PubMed1999

Purification, characterization, and gene analysis of a chitosanase (ChoA) from Matsuebacter chitosanotabidus 3001.

The extracellular chitosanase (34,000 M(r)) produced by a novel gram-negative bacterium Matsuebacter chitosanotabidus 3001 was purified. The optimal pH of this chitosanase was 4.0, and the optimal temperature was between 30 and 40 degrees C. The purified chitosanase was most active on 90% deacetylated colloidal chitosan and glycol chitosan, both of which were hydrolyzed in an endosplitting manner, but this did not hydrolyze chitin, cellulose, or their derivatives. Among potential inhibitors, the purified chitosanase was only inhibited by Ag(+). Internal amino acid sequences of the purified chitosanase were obtained. A PCR fragment corresponding to one of these amino acid sequences was then used to screen a genomic library for the entire choA gene encoding chitosanase. Sequencing of the choA gene revealed an open reading frame encoding a 391-amino-acid protein. The N-terminal amino acid sequence had an excretion signal, but the sequence did not show any significant homology to other proteins, including known chitosanases. The 80-amino-acid excretion signal of ChoA fused to green fluorescent protein was functional in Escherichia coli. Taken together, these results suggest that we have identified a novel, previously unreported chitosanase.

Amino Acid Sequence↗

PubMed1999

Characterization of a fission yeast SUMO-1 homologue, pmt3p, required for multiple nuclear events, including the control of telomere length and chromosome segregation.

Unlike ubiquitin, the ubiquitin-like protein modifier SUMO-1 and its budding yeast homologue Smt3p have been shown to be more important for posttranslational protein modification than for protein degradation. Here we describe the identification of the SUMO-1 homologue of fission yeast, which we show to be required for a number of nuclear events including the control of telomere length and chromosome segregation. A disruption of the pmt3(+) gene, the Schizosaccharomyces pombe homologue of SMT3, was not lethal, but mutant cells carrying the disrupted gene grew more slowly. The pmt3Delta cells showed various phenotypes such as aberrant mitosis, sensitivity to various reagents, and high-frequency loss of minichromosomes. Interestingly, we found that pmt3(+) is required for telomere length maintenance. Loss of Pmt3p function caused a striking increase in telomere length. When Pmt3p synthesis was restored, the telomeres became gradually shorter. This is the first demonstration of involvement of one of the Smt3p/SUMO-1 family proteins in telomere length maintenance. Fusion of Pmt3p to green fluorescent protein (GFP) showed that Pmt3p was predominantly localized as intense spots in the nucleus. One of the spots was shown to correspond to the spindle pole body (SPB). During prometaphase- and metaphase, the bright GFP signals at the SPB disappeared. These observations suggest that Pmt3p is required for kinetochore and/or SPB functions involved in chromosome segregation. The multiple functions of Pmt3p described here suggest that several nuclear proteins are regulated by Pmt3p conjugation.

Amino Acid Sequence↗

PubMed1999

Intravascular stenting of systemic venous baffle stenosis after corrective surgery for double outlet right ventricle with left isomerism.

A 14 year old girl with double outlet right ventricle, left isomerism, and complicated atrial anatomy had undergone corrective surgery with intra-atrial rerouting at 5 years of age. Cardiac catheterisation eight years after the surgery showed that she had two systemic venous baffle stenoses: between the hepatic vein and caval vein, and the caval vein and right atrium. Two Palmaz stents were successfully implanted percutaneously through a long sheath and a balloon catheter. The stenoses were relieved immediately and her symptoms quickly disappeared.

Adolescent↗

PubMed1999

Nitric oxide: a modulator, but not a mediator, of neurovascular coupling in rat somatosensory cortex.

We investigated the role of nitric oxide (NO)/cGMP in the coupling of neuronal activation to regional cerebral blood flow (rCBF) in alpha-chloralose-anesthetized rats. Whisker deflection (60 s) increased rCBF by 18 +/- 3%. NO synthase (NOS) inhibition by N(omega)-nitro-L-arginine (L-NNA; topically) reduced the rCBF response to 9 +/- 4% and resting rCBF to 80 +/- 8%. NO donors [S-nitroso-N-acetylpenicillamine (SNAP; 50 microM), 3-morpholinosydnonimine (10 microM)] or 8-bromoguanosine 3', 5'-cyclic-monophosphate (8-BrcGMP; 100 microM)] restored resting rCBF and L-NNA-induced attenuation of the whisker response in the presence of L-NNA, whereas the NO-independent vasodilator papaverine (1 mM) had no effect on the whisker response. Basal cGMP levels were decreased to 35% by L-NNA and restored to 65% of control by subsequent SNAP superfusion. Inhibition of neuronal NOS by 7-nitroindazole (7-NI; 40 mg/kg ip) or soluble guanylyl cyclase by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 100 microM) significantly reduced resting rCBF to 86 +/- 8 and 92 +/- 10% and whisker rCBF response to 7 +/- 4 and 12 +/- 3%, respectively. ODQ reduced tissue cGMP to 54%. 8-BrcGMP restored the whisker response in the presence of 7-NI or ODQ. We conclude that NO, produced by neuronal NOS, is a modulator in the coupling of neuronal activation and rCBF in rat somatosensory cortex and that this effect is mainly mediated by cGMP. L-NNA-induced vasomotion was significantly reduced during increased neuronal activity and after restoration of basal NO levels, but not after restoration of cGMP.

Animals↗

PubMed1999

Effects of imidazoline and non-imidazoline alpha-adrenergic agents on canine platelet aggregation.

Aggregatory and antiaggregatory effects of imidazol(in)e and non-imidazol(in)e alpha-adrenergic agents on canine platelets were examined turbidimetrically in citrated platelet-rich plasma or washed platelet solution. Each alpha-adrenoceptor agonist alone did not induce aggregation, but adrenaline and noradrenaline potentiated dose-dependently aggregation stimulated by ADP, collagen or thrombin. Small potentiation of ADP- or collagen-stimulated aggregation was also observed in response to oxymetazoline. The alpha2-adrenoceptor antagonists and/or imidazol(in)e alpha-adrenergic agents inhibit dose-dependently adrenaline-potentiated aggregation, whereas alpha1-adrenoceptor antagonists, a beta-adrenoceptor antagonist and non-imidazol(in)e alpha-adrenergic agents were no or less effective in inhibiting adrenaline-potentiated aggregation. The alpha2-adrenoceptor agonists did not reduce inhibitory effect of alpha2-adrenoceptor antagonists for adrenaline-potentiated aggregation. The alpha2-adrenoceptor antagonists and/or imidazol(in)es were no or less effective in inhibiting aggregation induced by ADP or thrombin alone. These results demonstrated that alpha2-adrenoceptor-blocking agents and/or imidazol(in)e alpha-adrenergic agents inhibit effectively the adrenaline-potentiated platelet aggregation.

Adenosine Diphosphate↗

PubMed1999

NC/Nga mice: a mouse model for atopic dermatitis.

Atopic dermatitis (AD) is a common pruritic disease that occurs primarily in infancy and childhood. AD is characterized by itching and the patient having an individual or family history of atopic diseases. Although AD is also frequently associated with elevated serum IgE levels and with common environmental factors contributing to its pathogenesis, the etiology of AD is still unknown. We examined NC/Nga mice (NC mice) that showed AD-like skin lesions with aging as a possible mouse model for AD. NC mice were maintained under conventional (Conv) or specific pathogen-free (SPF) conditions. Clinical symptoms, serum IgE levels and histopathology of the skin were compared between these 2 groups, and we explored their application as a model of human AD. It was found that the skin lesions of inbred NC mice were clinically and histologically very similar to human AD when the mice were raised under Conv conditions, but not under SPF conditions, and we assumed that some kinds of environmental factors might trigger AD-like signs and symptoms in NC mice. To further investigate the pathophysiology and treatment of AD, a suitable animal model is absolutely required, and NC mice are very useful for this purpose.

Aging↗

PubMed1999

Glucocorticoid inhibits oxidized LDL-induced macrophage growth by suppressing the expression of granulocyte/macrophage colony-stimulating factor.

Glucocorticoid, an anti-inflammatory agent, inhibits the development of atherosclerosis in various experimental animal models. This is partially explained by its ability to inhibit smooth muscle cell migration and proliferation in the intima and to reduce chemotaxis of circulating monocytes and leukocytes into the subendothelial spaces. We have recently demonstrated that oxidized LDL (Ox-LDL) has a mitogenic activity for macrophages in vitro in which Ox-LDL-induced granulocyte/macrophage colony-stimulating factor (GM-CSF) production plays an important role. Proliferation of cellular components is one of the characteristic events in the development and progression of atherosclerotic lesions. In the present study, we investigated the effects of glucocorticoids on Ox-LDL-induced macrophage growth. Dexamethasone, prednisolone, and cortisol inhibited Ox-LDL-induced thymidine incorporation into macrophages by 85%, 70%, and 50%, respectively. Ox-LDL induced a significant production of GM-CSF by macrophages, which was effectively inhibited by dexamethasone, prednisolone, and cortisol by 80%, 65%, and 50%, respectively. Dexamethasone-mediated inhibition of Ox-LDL-induced GM-CSF mRNA expression and macrophage growth was significantly abrogated by RU-486, a glucocorticoid receptor antagonist. Our results suggest that the inhibitory effects of glucocorticoids on macrophage growth may be due to the inhibition of Ox-LDL-induced GM-CSF production through transactivation of the glucocorticoid receptor.

Animals↗

PubMed1999

Altered pressure-natriuresis in obese Zucker rats.

It has not been examined whether the pressure-natriuresis response is altered in the insulin-resistant condition. Furthermore, despite an important role of nitric oxide (NO) in modulating pressure-natriuresis, no investigations have been conducted assessing the renal interstitial NO production in insulin resistance. The present study examined whether pressure-natriuresis was altered in insulin-resistant obese Zucker rats (OZ) and assessed the cortical and medullary nitrate/nitrite (NOx) levels with the use of the renal microdialysis technique. In OZ, serum insulin/glucose ratio (23.0+/-4.0x10(-8), n=9) and blood pressure (119+/-3 mm Hg) were greater than those in lean Zucker rats (LZ; 7.0+/-1.9x10(-8) and 103+/-4 mm Hg, n=9). The pressure-natriuresis curve in OZ was shifted to higher renal perfusion pressure (RPP), and the slope was blunted compared with that in LZ (0.073+/-0.015 vs 0.217+/-0.047 microEq/min kidney weight/mm Hg, P<0.05). The basal renal NOx level was reduced in OZ (cortex, 4.032+/-0.331 micromol/L; medulla, 4. 329+/-0.515 micromol/L) compared with that in LZ (cortex, 7.315+/-1. 102 micromol/L; medulla: 7.698+/-0.964 micromol/L). Furthermore, elevating RPP increased the medullary NOx in LZ, but this pressure-induced response was lost in OZ. Four-week treatment with troglitazone, an insulin-sensitizing agent, improved hyperinsulinemia, systemic hypertension, and basal renal NOx levels (cortex, 5.639+/-0.286 micromol/L; medulla, 5.978+/-0.284 micromol/L), and partially ameliorated the pressure-natriuresis curves; the slope of pressure-natriuresis curves and elevated RPP-induced NOx, however, were not corrected. In conclusion, our study suggests that insulin resistance is closely associated with abnormal pressure-natriuresis and hypertension. These deranged renal responses to insulin resistance are most likely attributed to impaired medullary NO production within the medulla.

Animals↗

PubMed1999

Effects of phyllodulcin, hydrangenol, and their 8-O-glucosides, and thunberginols A and F from Hydrangea macrophylla SERINGE var. thunbergii MAKINO on passive cutaneous anaphylaxis reaction in rats.

We examined the antiallergic effects of phyllodulcin, hydrangenol, and their 8-O-glucosides, and thunberginols A and F isolated from the processed leaves (Hydrangeae Dulcis Folium) and dried leaves of Hydrangea macrophylla SERINGE var. thunbergii MAKINO using the passive cutaneous anaphylaxis (PCA) reaction. With the exception of phyllodulcin, these constituents were found to significantly inhibit the PCA reaction. Although thunberginol A showed the most potent inhibitory effect, hydrangenol was considered to be the principal antiallergic component in the processed leaves, after taking into account their contents.

Animals↗

PubMed1999

The role of thunberginol A, an isocoumarin constituent of Hydrangeae Dulcis Folium, on the signal transmission pathway for rat mast cell degranulation.

The role of the signal transmission pathway of thunberginol A (TA) in mast cell degranulation was examined using rat peritoneal mast cells. First of all, we investigated the cellular distribution of TA using fluorescent microscopy. This indicated that TA is immediately incorporated into cells and distributes in cytosol around the nucleus. We then investigated the effect of TA on mast cell protein tyrosine phosphorylation, which is part of the signal transduction cascade for degranulation. TA non-specifically inhibited the tyrosine phosphorylation induced by compound 48/80 (Co. 48/80), at 10 to 100 microM, and orthovanadate/hydrogen peroxide at more than 50 microM in a dose-dependent manner. As far as the intracellular Ca2+ change in fluo-3-loaded cells was concerned, TA (10 microM) suppressed the rise in Ca2+ induced by antigens, ionomycin and thapsigargin, while TA did not suppress the rise induced by Co. 48/80. This evidence suggests that TA mainly inhibits extracellular Ca2+ influx, but TA does not act on the intracellular Ca2+ mobilization from the endoplasmic reticulum. We also investigated the influence of TA on the cytoskeleton and membrane changes using mast cells and erythrocytes. TA (10 microM) inhibited the cytoskeletal assembly formation in dicyanovinyl julolidin-loaded mast cells induced by Co. 48/80. Moreover, TA suppressed the hypotonic hemolysis of erythrocytes, from 3 to 1000 microM, in a dose-dependent manner. These results suggest that inhibition of protein tyrosine phosphorylation, extracellular Ca2+ influx and cytoskeletal assembly formation, and membrane stabilization are involved in the inhibitory effect of TA in mast cell degranulation.

Animals↗

PubMed1999

Antidiabetic principles of natural medicines. IV. Aldose reductase and qlpha-glucosidase inhibitors from the roots of Salacia oblonga Wall. (Celastraceae): structure of a new friedelane-type triterpene, kotalagenin 16-acetate.

The aqueous methanolic extract of an Indian natural medicine, the roots of Salacia oblonga Wall. (Celastraceae), was found to show inhibitory activity on the increase in serum glucose level in sucrose- and maltose-loaded rats. The water-soluble and ethyl acetate-soluble portions from the aqueous methanolic extract showed inhibitory activities on alpha-glucosidase and aldose reductase, respectively. From the water-soluble portion, potent alpha-glucosidase inhibitors, salacinol and kotalanol, were isolated, together with nine sugar related components, while a new friedelane-type triterpene, kotalagenin 16-acetate, was isolated from the ethyl acetate-soluble portion along with known diterpenes and triterpenes. The structure of kotalagenin 16-acetate was elucidated on the basis of physicochemical evidence. Principal components from this natural medicine were examined in terms of inhibitory activity on aldose reductase, and the diterpene and triterpene constituents, including the new kotalagenin 16-acetate, were found to be responsible components for the inhibitory activity on aldose reductase.

Aldehyde Reductase↗

PubMed1999

Bioactive saponins and glycosides. XIV. Structure elucidation and immunological adjuvant activity of novel protojujubogenin type triterpene bisdesmosides, protojujubosides A, B, and B1, from the seeds of Zizyphus jujuba var. spinosa (Zizyphi Spinosi Semen).

Following the elucidation of jujubosides A1 and C and acetyljujuboside B, novel protojujubogenin type triterpene bisdesmosides, protojujubosides A, B, and B1, were isolated from Zizyphi Spinosi Semen, the seeds of Zizyphus jujuba Mill. var. spinosa Hu. The structures of protojujubosides A, B, and B1 were determined on the basis of chemical and physicochemical evidence, which included the conversion of protojujubosides to known jujubosides using enzymatic hydrolysis. Protojujubosides A and jujubosides A, B, and C were found to show potent immunological adjuvant activity.

Adjuvants, Immunologic↗