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T Miyazaki

Publications and source records attributed to T Miyazaki.

At least 217 records · Page 12Linked to original sources
PubMed1998

Antiallergic activities of rabdosiin and its related compounds: chemical and biochemical evaluations.

We examined the effects of caffeic acid-containing compounds such as chlorogenic acid, rosmarinic acid and rabdosiin on anti-allergic activities involving active oxygens scavenging activity as well as inhibitory activities of hyaluronidase and beta-hexosaminidase release. Rabdosiin exhibited the highest hyaluronidase-inhibitory activity and scavenging activities against active oxygens species such as superoxide anion radicals and hydroxyl radicals among the tested compounds. Both rabdosiin and caffeic acid inhibited beta-hexosaminidase release from cultured cells more than 90% at 2 mM. The inhibition by rosmarinic acid and chlorogenic acid were weaker than that of rabdosiin. From these results, rabdosiin has been proposed to possess anti-allergic activity.

Animals↗
PubMed1998

The effects of gonadotropin-releasing hormone agonist on androstenedione production and follicular development during controlled ovarian hyperstimulation.

PURPOSE: We performed a prospective randomized study to assess the effects of a GnRH agonist (GnRH-a) on follicular development and steroidogenesis during controlled ovarian hyperstimulation (COH). METHODS: Patients undergoing in vitro fertilization (IVF) for tubal infertility received human menopausal gonadotropin (hMG) stimulation with or without the GnRH-a, buserelin, beginning in the midluteal phase of the prior cycle. We analyzed serum hormone levels, follicular development, and outcome of IVF. RESULTS: The mean number of retrieved oocytes was significantly greater, and the implantation rate per embryo was significantly higher, in the GnRH-a/hMG group (n = 101) than in the hMG-only group (n = 97). The concentration of androstenedione (A) and the A/estradiol ratio in the serum were significantly lower in the GnRH-a treatment group throughout the follicular phase. CONCLUSIONS: The concomitant use of GnRH-a during COH prevents atretic change of the follicles and enhances follicular development by reducing androgen accumulation, resulting in a higher developmental competence of the oocytes.

Adult↗
PubMed1998

Adsorption of complement, cytokines, and proteins by different dialysis membrane materials: evaluation by confocal laser scanning fluorescence microscopy.

The membranes tested in the present study were cellulose triacetate (CTA), polymethylmethacrylate (PMMA), and polyacrylonitrile (PAN). The adsorption by each membrane of albumin, IgG, C3a, interleukin-1beta (IL-1beta), interleukin-6 (IL-6), human neutrophil elastase (HNE), and tumor necrosis factor alpha (TNFalpha) was examined and semiquantitatively graded by confocal laser scanning fluorescence microscopy (CLSFM). After clinical use the dialyzers were treated with antibodies for these proteins and cytokines. Then the samples were incubated with fluorescein isothiocyanate-labeled anti-IgG antibody and observed by CLSFM. The changes in the blood levels of C3a and cytokines were also studied. In the CTA membrane, the adsorption of these substances, except for albumin and HNE, was less than in the synthetic membranes. The PAN membrane revealed the most abundant adsorption, especially for IL-1beta, IL-6, and TNFalpha. Although a marked elevation of C3a in the blood was observed in the CTA membrane, considerable adsorption was evident in the PMMA and the PAN membranes. Because the changes in the blood levels could be affected by membrane adsorption, both the blood levels and the adsorption of the biocompatibility parameters should be evaluated when membrane biocompatibility is discussed.

Acrylic Resins↗
PubMed1998

Power and colour Doppler ultrasonography for the evaluation of the vasculature of the human corpus luteum.

We used power Doppler imaging to examine neovascularization in the corpus luteum (CL) in 12 healthy volunteers. We also investigated whether CL blood flow reflected luteal function. The ratio of the area of vessels in the CL to the area of a sectional plane at the maximum diameter of the CL observed by power Doppler (FA ratio) was used as a quantitative index of the vascularity of the CL. The pulsatility index (PI) was significantly lower in ovarian arteries with CL than without CL (P < 0.05). Changes in ovarian arterial and intra-luteal PI appeared to reflect physiological changes in the vasculature of the CL. There was no correlation between the volume of the CL or the FA ratio and the concentration of progesterone. The pattern of changes in the product of the FA ratio and the CL volume and in the progesterone concentration was similar. The progesterone concentration was positively correlated with this product (r = 0.74, P < 0.01). The product of the FA ratio and the CL volume plateaued during the mid- to late luteal phase, suggesting the presence of functional and structural luteolysis. These findings suggest that colour Doppler ultrasonography, including power Doppler imaging, can detect physiological changes in the blood flow of the ovary in the luteal phase, and may be a useful noninvasive tool for evaluating CL function.

Adult↗
PubMed1998

Interpretation of accelerants in blood of cadavers found in the wreckage after fire.

Accelerants in the blood of 73 cadavers found in wreckage after fire were analyzed by gas chromatography (GC) and a combination of gas chromatography-mass spectrometry (GC-MS) to decide whether accelerants containing petroleum components had been used and whether the cadavers had been exposed to fire before or after death. In 16 of 26 cases in which accelerants were used to start a fire before death, accelerants were detected in the blood. In 7 cases in which accelerants were used to start a fire, the victims were determined to have been exposed to the vapor of accelerants after death because no accelerants were detected in the blood, no soot was found in the airways, and carboxyhemoglobin (COHb) concentrations were not higher than those found in smokers. In 9 of 34 cases in which accelerants were suspected to have been used to start a fire before death, accelerants were detected in the blood. When soot is not detectable by the unaided eye in the airways of a victim found in debris of a fire in which the use of accelerants is suspected, or the COHb concentration in the blood is no higher than in a smoker, analysis of accelerants in the blood seems to be helpful in determining the cause of death and whether inflammable were used.

Adolescent↗
PubMed1998

Postoperative chemotherapy may improve prognosis in unresectable gastric cancer.

We have retrospectively evaluated to prognosis of patients with unresectable gastric cancer (UGC) and the effect of postoperative chemotherapy on that prognosis. One hundred patients who died of UGC included 37 patients who received postoperative chemotherapy (chemotherapy group) and 63 patients who did not receive postoperative chemotherapy (control group). Chemotherapy regimens were as follows: intravenous mitomycin (MMC) plus 5-fluorouracil (5-FU) (n=15), oral 5-FU alone (n=10), intravenous methotrexate (MTX) plus 5-FU (n=8), intravenous cisplatin plus 5-FU (n=2), and hepatic arterial infusion of 5-FU plus oral 5-FU (n=2). No prior chemotherapy or radiation therapy was given. All patients' cancers were stage IV. Median survival of the chemotherapy group (238 days) was significantly longer than the control group (137 days). The 1-year survival rate in the treated group was 19.0% but only 2.4% in the control group (p < 0.01). Patients with palliative gastrojejunostomy did not survive significantly longer than those having laparotomy alone or ileal tube insertion. We conclude that the prognosis for patients with UGC remains very poor, but postoperative chemotherapy may contribute to prolonged survival in patients with UGC.

Adenocarcinoma↗
PubMed1998

Involvement of interleukin-8 in dialysis-related arthritis.

To elucidate the role of interleukin (IL)-8, a chemotactic factor for neutrophils, in dialysis-related arthritis (DRA) of patients on long-term hemodialysis, the concentration of IL-8 was measured in the synovial fluids of DRA patients with acute arthralgia and joint swelling, and was compared with those in patients with rheumatoid arthritis (RA) and patients with osteoarthritis (OA). We noted a marked elevation of IL-8 in the joint fluids of patients with DRA and RA as compared with OA. Furthermore, to determine the role of IL-8 in synovitis, we examined the in vivo effect of intra-articular injection of human recombinant IL-8 on leukocyte infiltration into the joint space of rabbits. A single injection of IL-8 to the joints of rabbits induced rapid infiltration of neutrophils into the joint space and synovial tissues, which reached a maximum in four hours. The oral administration of indometacin farnesil (a prodrug that is converted to indomethacin after intestinal absorption) before the injection of IL-8 alleviated the infiltration of neutrophils. When human synovial cells were incubated with tumor necrosis factor (TNF)-alpha, the expression of IL-8 mRNA and IL-8 production in the cultured synovial cells were increased. The TNF-alpha-stimulated expression of IL-8 mRNA and IL-8 production in the cultured synovial cells were markedly inhibited by dexamethasone. In conclusion, IL-8 levels were markedly elevated in the joint fluids of patients with DRA. Interleukin-8 released from synovial cells may be an important factor to induce acute inflammation in DRA. Dexamethasone and indomethacin may be effective for DRA by inhibiting the production and chemotactic actions of IL-8, respectively.

Adult↗
PubMed1998

Differential role of epicardial and endocardial K(ATP) channels in potassium accumulation during regional ischemia induced by embolization of a coronary artery with latex.

INTRODUCTION: K(ATP) channels are activated predominantly in the epicardium during regional ischemia. Therefore, the role of K(ATP) channels in ischemia-induced rise of extracellular potassium concentration ([K+]o) might be greater in the epicardium. METHODS AND RESULTS: In 18 anesthetized dogs, the left anterior descending coronary artery (LAD) was ligated, followed by injection of 23-microm latex beads into the occluded artery to interrupt collateral flow, by which accumulated [K+]o might wash out. Epicardial and endocardial [K+]o were measured during a 20-minute period of ischemia using a valinomycin membrane. The dogs were divided into three groups: 6 control dogs (CTRL); 7 dogs pretreated with intravenous glibenclamide (0.3 mg/kg [GLIB]), a blocker of K(ATP) channels; and 5 dogs pretreated with intravenous nicorandil (0.2 to 0.25 mg/kg [NCR]), a K(ATP) channel opener. Before LAD occlusion, there was no difference in [K+]o among the three groups. In the control group, epicardial and endocardial [K+]o were increased to a similar level as a function of time after occlusion (CTRL) at both layers. Ischemia-induced epicardial [K+]o rise was suppressed by GLIB (8.4+/-0.4 vs 6.7+/-0.5 mM, P < 0.05) but augmented by NCR (12.9+/-2.0 mM, P < 0.05). In contrast, endocardial [K+]o rise remained unaffected (7.6+/-0.2 mM CTRL, 7.6+/-1.3 mM GLIB, and 9.4+/-2.2 mM NCR, P = NS). CONCLUSION: Activation of K(ATP) channels plays an important role in epicardial [K+]o rise, but not in endocardial [K+]o rise, during regional ischemia. Another mechanism(s) may be important for endocardial [K+]o accumulation.

Adenosine Triphosphate↗
PubMed1998

Catheter ablation of accessory atrioventricular connection between right atrial appendage to right ventricle: a case report.

A 24-year-old woman had experienced frequent attacks of orthodromic AV reciprocating tachycardia. The polarity of the delta waves suggested a right anterior or anterolateral accessory pathway. After ablation at the tricuspid annulus was unsuccessful, earliest retrograde atrial activation was recorded on the floor of the right atrial appendage, 2 cm above the tricuspid ring. Application of radiofrequency energy at this site abolished accessory pathway conduction. This unusual accessory pathway, located between the floor of the right atrial appendage and the right ventricle, was amenable to radiofrequency catheter ablation from within the right atrial appendage.

Adult↗
PubMed1998

[Retropharyngeal abscess in an adult and an elderly woman].

Retropharyngeal abscess is reported to be decreasing in frequency in recent years. We report two cases of retropharyngeal abscess that were diagnosed within four years in Department of Otorhinolaryngology, Gifu University Hospital. Case 1 was a 36-year-old male who was suggested to have an abscess as primary infection and case 2 was a 71-year-old female whose abscess seemed to be a secondary infection following unknown primary infection. Endoscopic or open neck drainage as well as antibacterial chemotherapy mainly with combinations of flomoxef and clindamycin in the case 1 and piperacillin and clindamycin in the case 2 was successfully carried out. They were discharged an 15-day and 24-day after operation in the cases 1 and 2, respectively. A 30 min. culture after sample collection on operation demonstrated aerobe-anaerobe mixed infection in both cases; three aerobes and four anaerobes in the case 1 and three aerobes and two anaerobes in the case 2. These results suggest that retropharyngeal abscess may be a complicated infection involving more bacterial species than has been commonly believed. Measuring susceptibility of isolates to antimicrobial agents, a strain of Capnocytophaga sp. and a strain of anaerobic gram-negative rod were highly resistant to piperacillin, cefroxine and ofloxacin. It is important for adequate antibacterial chemotherapy to grasp the bacteriology of retropharyngeal abscess and analyze susceptibility of antimicrobial agents.

Adult↗
PubMed1998

In vitro and in vivo antidermatophyte activities of NND-502, a novel optically active imidazole antimycotic agent.

In vitro and in vivo antidermatophyte activities of NND-502, a new imidazole antimycotic agent, were compared with those of two existing antifungal agents, lanoconazole and terbinafine. NND-502 exhibited strong in vitro antifungal activity against Trichophyton spp.; its MIC was 1 to 4 times lower than that of lanoconazole or terbinafine. In an in vivo study with a guinea pig model of tinea pedis, 7-day topical treatment with a 0.5% solution of NND-502 (dissolved in polyethylene glycol 400) was more effective than that with a 0.5% solution of either lanoconazole or terbinafine for eradicating fungi from the infected feet. When the duration of treatment was shortened to 3 days, a topical 1% solution of NND-502 achieved a complete mycological cure, while topical 1% solutions of lanoconazole and terbinafine did not.

Animals↗
PubMed1998

A critical role for cyclin C in promotion of the hematopoietic cell cycle by cooperation with c-Myc.

Cyclin C, a putative G1 cyclin, was originally isolated through its ability to complement a Saccharomyces cerevisiae strain lacking the G1 cyclin gene CLN1-3. Unlike cyclins D1 and E, the other two G1 cyclins obtained by the same approach and subsequently shown to play important roles during the G1/S transition, there is thus far no evidence to support the hypothesis that cyclin C is indeed critical for the promotion of cell cycle progression. In BAF-B03 cells, an interleukin 3 (IL-3)-dependent murine pro-B-cell line, cyclin C gene mRNA was induced at the G1/S phase upon IL-3 stimulation and reached a maximal level in the S phase. Enforced expression of exogenous cyclin C in this cell line failed to alter its growth properties. In the present study, we examined whether cyclin C is capable of cooperating with the cytokine-responsive immediate-early gene products c-Myc and c-Fos in the promotion of cell proliferation. We found that cyclin C is able to cooperate functionally with c-Myc, but not c-Fos, to induce both BAF-B03 cell proliferation in a cytokine-independent fashion and the formation of cell clusters. Furthermore, cyclin C was primarily responsible for the induction of cdc2 gene expression. Our data define a novel role for cyclin C in the regulation of both the G1/S and G2/M phases of the cell cycle, and this effect appears to be independent of the activity of CDK8 in the control of transcription.

Animals↗
PubMed1998

Hereditary dominance of fast-twitch fibers in skeletal muscles and relation of thyroid hormone under physiological conditions in rats.

To investigate whether muscle fiber compositions of various skeletal muscles were correlated with each other and whether muscle fiber type composition was related to the serum thyroid hormone level, fast-twitch fiber dominant rats (FFDR), which had a higher percentage of fast-twitch (FT) fibers in the deep portion of the lateral head of the gastrocnemius muscle (GAS), were compared to a control group. The FFDR group was obtained by the selective breeding for high-percentage FT fibers in the GAS, and the control group was obtained by random breeding from the same base population. The percentages of FT fibers of the GAS, soleus (SOL), vastus intermedius (VI), biceps brachii (BB), rectus abdominis (RA) and extensor digitorum longus (EDL) muscles were analyzed. The percentages of FT fibers of the GAS, SOL, VI and BB in the FFDR group were significantly higher than in the control group (p<0.05), and percent FT fibers of the GAS were significantly correlated with those of the SOL (r = 0.62, p<0.01), VI (r = 0.45, p <0.05) and BB (r = 0.43, p<0.05). On the other hand, no significant differences between FFDR and the control group and no significant correlations with the GAS were observed in percent FT fibers of the RA and EDL. The total 3,3',5-triiodo-L-thyronine (T3) level in FFDR was not significantly different from the control group and was not significantly correlated with the percentage of FT fibers. These data suggest that the percentages of FT fibers of various skeletal muscles are genetically correlated with each other, but some FT muscles are not because they might be close to the upper limits of the genetic adaptive range. In addition, percentages of FT fibers are independent of the total T3 level under physiological conditions.

Animals↗
PubMed1998

Role of beta 1 integrins in human endometrium and decidua during implantation.

The present study was undertaken to investigate the expression and function of beta 1 integrins in human endometrium and decidua. Fluorescence-activated flow cytometry demonstrated the greater expression of the beta 1, alpha 1, alpha 2, and alpha 5 subunits of the beta 1 integrin family in cultured stromal cells from the midsecretory phase than in those of the early proliferative phase. The addition of estradiol (E2) and progesterone (P) to cultured stromal cells in the early proliferative phase increased the expression of beta 1 integrins in vitro. The immunohistochemical distribution of beta 1 integrins demonstrated predominantly glandular epithelial staining in the proliferative phase, and stromal and glandular staining in the midsecretory phase. Flow cytometry also demonstrated the expression of beta 1, alpha 1, alpha 2, alpha 3, alpha 5, and alpha 6 subunits of beta 1 integrin family in cultured decidual cells. Immunohistochemistry confirmed the beta 1 integrin cell surface phenotypes in cultured decidual cells observed by flow cytometry. In the subsequent experiment, the effects of antibodies against specific beta 1 integrin heterodimers on mouse embryo attachment and spreading were tested to identify the role of beta 1 integrins in early implantation. We developed assays for the attachment of mouse embryos and for trophoblastic spreading on cultured human decidual cells. The addition of antibodies directed against beta 1 and alpha integrin subunits to cultured decidual cells did not affect the rates of hatching or attachment of the blastocysts, whereas the outgrowth of embryos on the decidual cells was inhibited by their antibodies in a dose-dependent manner. Thus, beta 1 integrin in human endometrium and decidua may be important in mediating the organization of extracelllar matrix proteins derived from embryos during the early stage of implantation.

Adult↗
PubMed1998

Expression of inhibitor of apoptosis proteins (IAPs) in rat granulosa cells during ovarian follicular development and atresia.

The inhibitor of apoptosis proteins (IAPs) constitute a family of highly conserved apoptosis suppressor proteins that was originally identified in baculoviruses. Although IAP homologs have been recently identified and demonstrated to suppress apoptosis in mammalian cells, their expression and role during follicular development and atresia are unknown. The present study was conducted to address these questions. Using established in vivo models for the induction of follicular development and atresia in immature rats, it was possible to compare the immunolocalization of X-link inhibitor of apoptosis protein (Xiap) and human inhibitor of apoptosis protein-2 (Hiap-2), two members of the IAP family, at defined stages of follicular maturation and to relate the differences observed with those of follicular cell proliferation and apoptosis [as determined by proliferating cell nuclear antigen (PCNA) immunohistochemistry and in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin end labeling (TUNEL), respectively]. In addition, granulosa cell DNA and proteins were assessed for apoptotic fragmentation by 3'-end labeling/agarose gel electrophoresis (DNA ladder) and Hiap-2 and Xiap protein content by Western blot analysis, respectively. Hiap-2 and Xiap expression in both granulosa and theca cells increased with follicular maturation, reaching maximal levels at the antral stage of development. The immunoreactivity for PCNA, Xiap, and Hiap-2 decreased markedly in atretic (TUNEL-positive) follicles at the small to medium sized antral stage of development, suggesting follicular atresia may be associated with decreased granulosa cell IAP protein content and decreased proliferation. Atresia was also associated with a change in the intracellular distribution of IAPs in granulosa cells. Biochemical analysis of DNA fragmentation (DNA ladder) in granulosa cells from preantral and early antral follicles indicates extensive apoptosis that was associated with minimal IAP protein content. Gonadotropin treatment increased Hiap-2 and Xiap protein content and suppressed apoptosis in granulosa cells, resulting in the development of follicles to the antral and preovulatory stages. In addition, gonadotropin withdrawal induced apoptotic DNA fragmentation in granulosa cells in early antral and antral follicles, which is accompanied by a marked decrease in Hiap-2 and Xiap expression. These data suggest that IAPs may be involved in the suppression of granulosa cell apoptosis by gonadotropin in small to medium-sized antral follicles and play an important role in determining the fate of the cells, and thus also the eventual follicular destiny (atresia vs. ovulation).

Animals↗
PubMed1998

Upper cervical myelopathy associated with low CSF pressure: a complication of ventriculoperitoneal shunt.

A patient who had undergone ventriculoperitoneal shunting developed upper cervical myelopathy. His CSF pressure was markedly low, and deformation of the spinal cord and shrinkage of the subarachnoid space at the upper cervical level were found in radiologic examinations. Ligation of the shunt tube resulted in almost complete recovery. The effect of excessive drainage may have caused the abnormalities.

Cerebral Ventriculography↗
PubMed1998

Development of in vitro fertilized feline embryos in a modified Earle's balanced salt solution: influence of protein supplements and culture dishes on fertilization success and blastocyst formation.

The effects of protein supplements and culture dish type on in vitro fertilization (IVF) and embryo development in culture were examined in the domestic cat. In Experiment I, follicular oocytes were fertilized and cultured in either 1) modified Earle's balanced salt solution, designated MK-1, supplemented with one of the following: 10% human serum (HS), 10% FCS or 0.4% BSA, or 2) Medium 199 (M-199) supplemented with 10% FCS. Fertilization rates were lower (P < 0.01) in MK-1 + BSA (74.4%), MK-1 + FCS (56.1%), and M-199 + FCS (51.4%) than in MK-1 + HS (94.7%). A greater (P < 0.01) percentage of blastocysts was obtained in MK-1 + HS (50.0%) than in other treatment groups (range, 4.3-17.2%). In Experiment II, the effect of dish type (tissue culture dish, TCD, versus suspension culture dish, SCD) on embryo development was evaluated in MK-1 supplemented with either HS or BSA. Significantly higher proportions of IVF-derived embryos developed to blastocysts at 120 and 144 hr post-insemination, respectively, when cultured in HS/SCD (47.2 and 71.7%) than in BSA/SCD (11.4 and 27.3%) or BSA/TCD (10.4 and 25.0%). At 120 hr post-insemination, there was a lower (P < 0.01) percentage of blastocysts in HS/TCD (22.2%) than in HS/SCD. In Experiment III, six embryos per cat were transferred to the uterine horns of 17 recipients at 144 hr after hCG treatment. Five of 7 recipients which received late morulae cultured in MK-1 + BSA (SCD) for 120 hr became pregnant (71.4%). Eight of 10 recipients which received early blastocysts cultured in MK-1 + HS (SCD) for 120 hr became pregnant (80.0%). We conclude that MK-1 containing HS is highly beneficial for overcoming the in vitro developmental block of IVF-derived feline embryos and increasing the success rate of IVF/ET.

Animals↗