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A Miyazaki

Publications and source records attributed to A Miyazaki.

At least 55 records · Page 3Linked to original sources
PubMed2000

Enamel matrix derivative in the treatment of human intrabony osseous defects.

BACKGROUND: There is limited information available from clinical trials regarding the performance of enamel matrix derivative (EMD) in the treatment of periodontal intrabony defects. This randomized, double-blind, placebo-controlled, split-mouth study was designed to compare the clinical and radiographical effects of EMD treatment to that of placebo-controlled treatment for intrabony defects. METHODS: Sixteen patients were included, each of whom had 1 or 2 pairs of intrabony defects located contralaterally in the same arch. Thirty-six intrabony defects were randomly assigned treatment with flap surgery plus EMD or flap surgery plus placebo. At baseline and at the 12-month follow-up evaluation visit, clinical and radiographic measurements were determined. Data were statistically analyzed using the Wilcoxon-signed rank test (alpha = 0.05). RESULTS: At the 12-month visit, bleeding on probing for the EMD group was 0.11 +/- 0.32 compared to the placebo group, 0.61 +/- 0.50 (P <0.05). Probing depth reduction was greater in the EMD group (3.00 +/- 0.97 mm) compared to the placebo group (2.22 +/- 0.81 mm) (P <0.05). Mean values for clinical attachment gain in the EMD and the placebo groups were 1.72 +/- 1.07 mm and 0.83 +/- 0.86 mm, respectively (P <0.05). Vertical relative attachment gain was 38.5 +/- 22.6% in the EMD group and 21.4 +/- 25.2% in the placebo group (P<0.05). Radiographic bone density gain was greater in the EMD (20.2 +/- 16.6%) compared to the placebo group (-3.94 +/- 23.3%) (P<0.01). CONCLUSIONS: Treatment with flap surgery and EMD, compared to flap surgery with placebo, produced a significantly more favorable clinical improvement in intrabony periodontal defects.

Adult↗
PubMed2000

Long-term (14 years) effect of LDL apheresis on obstructive changes in aortocoronary saphenous-vein bypass grafts in a case of heterozygous familial hypercholesterolemia with the LDL receptor proline664 to leucine mutation.

A 61-year-old Japanese woman with heterozygous familial hypercholesterolemia (FH), type 2 diabetes mellitus and coronary artery disease underwent coronary artery bypass grafting (CABG) utilizing a saphenous vein graft at the age of 46, in June 1984, 6 months before low density lipoprotein (LDL) apheresis was started. She had received LDL apheresis every two weeks, along with combined drug treatment since the age of 47 (December 1984). She had bilateral xanthelasma and Achilles tendon xanthomas. Her fasting baseline serum total cholesterol and triglyceride level were 464 mg/dl and 57 mg/dl, respectively at the age of 47 when she visited our hospital for the first time. Analysis of the genomic DNA from the patient revealed heterozygous amino acid substitution of Leu for Pro664 in the LDL receptor gene. She was diagnosed as type 2 diabetes mellitus at the age of 53. Combined treatment in the steady state yielded a pretreatment LDL cholesterol level of 230+/-14 mg/dl and a posttreatment level of 57+/-7.6. All grafts were widely patent after as long as 14 years since CABG, suggesting that LDL apheresis combined with drug therapy is highly effective in preventing the occlusion of bypass grafts in a patient with heterozygous FH and type 2 diabetes mellitus.

Aorta↗
PubMed2000

Evaluation of aberrant bile ducts before laparoscopic cholecystectomy: helical CT cholangiography versus MR cholangiography.

OBJECTIVE: The purpose of our study was to compare the accuracy of helical CT cholangiography and that of MR cholangiography in the diagnosis of aberrant bile ducts or cystic ducts before laparoscopic cholecystectomy. SUBJECTS AND METHODS: A total of 120 consecutive patients, including 114 patients with cholecystolithiasis and six with gallbladder polyps, were treated using laparoscopic cholecystectomy between November 1996 and August 1998. Eighteen (15%) of the 120 patients were suspected of having aberrant bile ducts or cystic ducts on helical CT cholangiography, and 16 of these 18 patients were subsequently examined on MR cholangiography. For the 16 patients who underwent both imaging examinations, findings from helical CT cholangiography and MR cholangiography were compared with intraoperative cholangiography. RESULTS: Aberrant bile ducts in 13 patients and aberrant cystic ducts in three patients were divided into six types on the basis of the results of intraoperative cholangiography. Although these types were clearly identified using helical CT cholangiography in all 16 patients, the anatomic variants were not correctly identified in seven (44%) of the 16 patients with MR cholangiography. False-negative findings were mainly a result of the insertion sites of the cystic ducts or aberrant bile ducts being obscured by aberrant bile ducts or duodenum. Two (2%) of the 120 patients developed mild adverse reactions to the contrast material, but neither required treatment. CONCLUSION: Helical CT cholangiography clearly showed aberrant bile ducts and cystic ducts, but visualization of these structures on MR cholangiography was unsatisfactory because of overlapping duodenum and hepatic ducts.

Adult↗
PubMed2000

Hb Ernz [beta123(H1)Thr-->Asn] and Hb Renert [beta133(H11)Val-->Ala]: two new neutral variants revealed by reversed phase high performance liquid chromatography analysis.

Analysis of globin chains by reversed phase high performance liquid chromatography, used as an additional tool for characterizing hemoglobin variants, has led to the discovery of a new class of variants that display only differences in hydrophobicity. Two such variants are here described. Hb Ernz was found in a man of Italian origin who was polycythemic, and in two of his three daughters who were hematologically normal. Hb Renert, a slightly unstable variant, was found in a man from Cape Verde who also carried Hb S and presented with chronic hemolysis. The structural abnormalities were characterized by protein structure methods involving reversed phase high performance liquid chromatographic separations of globins and peptides, followed by mass spectrometry studies (electrospray, ion trap, tandem mass spectrometry).

Chromatography, High Pressure Liquid↗
PubMed2000

[Alleviation of sadness by pleasant imagery: analyses of subjective and physiological responses].

This study examined whether elicitation of joy or relaxation would reduce intensity of formerly induced sadness by using imagery tasks. Participants (N = 10) imaged a series of four sad scenes successively in the preliminary experiment. Dependent variables were subjective emotional ratings, heart rate, and facial electromyography of the corrugator and the zygomatic muscles. The result indicated that the sadness-imageries increased heart rate, corrugator activity, and zygomatic activity, as well as sad feeling. The procedure of the main experiment (N = 19) was almost the same as that of the preliminary experiment except that the sadness-imageries were followed by one of the 3 emotional imageries, that is, relaxation, neutrality, and joy. The result indicated that the relaxation-imagery marginally significantly decreased the heart rate that had been increased by the sadness-imageries. The joy-imagery reduced sad feeling but increased the zygomatic activity more than the relaxation-imagery. No effect was found on the heart rate. These results suggested that positive emotions alleviate sadness, and that joy and relaxation alleviate different aspects of sadness.

Adult↗
PubMed2000

Epithelial-mesenchymal interaction in gastric mucosal restoration.

In this review article we discuss the role of growth factors in gastric ulcer healing using an in vitro wound repair model with gastric epithelial and mesenchymal cells. Several growth factors accelerate gastric epithelial and mesenchymal wound healing in vitro with acceleration of cell migration and proliferation. Epidermal growth factor, transforming growth factor-alpha (TGFalpha), hepatocyte growth factor, and insulin accelerate predominantly gastric epithelial wound healing; and TGFbeta and basic fibroblast growth factor predominantly accelerate gastric mesenchymal wound healing. Platelet-derived growth factor-betabeta and insulin-like growth factor-1 (IGF-1) accelerate both significantly. Among these growth factors, IGF-1 produced from fibroblasts plays a key role in the gastric epithelial-mesenchymal interaction during the process of gastric wound healing.

Animals↗
PubMed2000

Vertical profile of dioxin-like and estrogenic potencies in a sediment core from Tokyo Bay, Japan.

Dioxin-like and estrogenic activities were measured in a sediment core collected from Tokyo Bay using in vitro bioassays after fractionating sediment extracts into three fractions by florisil column chromatography. Target analytes including polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polycyclic aromatic hydrocarbons (PAHs) and nonylphenol (NP) were measured by gas chromatography-mass spectrometry (GC-MS) or high performance liquid chromatography (HPLC) techniques. NP concentrations were greater in surface sediments (0 to 12 cm) than those in sub-surface (12-30 cm). The maximum observed PCN concentration was 5 ng/g, whereas that of PCBs was 300 ng/g. Concentrations of PCBs in fraction 1 (F1) were not high enough to induce significant luciferase activities in H4IIE-luc cells. Significant dioxin-like activities were found in fractions 2 (F2) and 3 (F3). PAH concentrations were correlated with dioxin-like activities measured in F2. Compounds that contribute to the dioxin-like activities in F3 were not identified yet. Significant estrogenic activities were observed in F2 samples, which may be related to the presence of certain estrogenic PAHs. F3 samples were cytotoxic to MCF-7 cells and therefore their estrogenic potential could not be estimated.

Animals↗
PubMed1999

Tin speciation in the femtogram range in open ocean seawater by gas chromatography/inductively coupled plasma mass spectrometry using a shield torch at normal plasma conditions.

A sensitive method for the determination of ultratrace organotin species in seawater is described. The merits and demerits of derivatization methods using Grignard reagent or sodium tetraethylborate (NaBEt4) were evaluated in terms of derivatization efficiency, applicability to the programmed temperature vaporization (PTV) method, and procedural blanks. The sensitivity of the gas chromatography/inductively coupled plasma mass spectrometry (GC/ICPMS) was improved by more than 100-fold by operating the shield torch at normal plasma conditions, compared with that obtained without using it. The absolute detection limit as tin reached subfemtogram (fg) levels. Furthermore, the detection limit in terms of relative concentration was improved 100-fold by using the PTV method, which enabled the injection of a large sample volume of as much as 100 microL without loss of analyte. When the organotin species in seawater were extracted into hexane with a preconcentration factor of 1000 after ethylation with NaBEt4 and a 100 microL aliquot of the extract was injected into the GC, the instrumental detection limit in relative concentration reached 0.01 pg/L in original seawater. Sources of contamination of organotin species during the sample preparation were examined, and a purification method of NaBEt4 was developed. Finally, the method was successfully applied to open ocean seawater samples containing organotin species at the level of 1-100 pg/L.

Borates↗
PubMed1999

Effects of Anions on Local Structure of Al and Si in Aluminosilicates.

Three kinds of amorphous aluminosilicates were synthesized by coprecipitation of silicic acid with aluminum hydroxide in the presence of different inorganic ions: sulfate, chloride, and nitrate. Although the bulk composition of the aluminosilicates obtained was not affected by anion species, their DTA spectra were significantly different, suggesting that their structures also differ. The local structure of Al and Si in the aluminosilicates was studied in detail by 27Al and 29Si MAS NMR. From the 27Al MAS NMR spectra and comparison between 29Si HD- and CP-MAS NMR spectra, it was concluded that the aluminosilicate obtained in the presence of sulfate ions has only a montmorillonite-like structure, whereas in the cases of chloride and nitrate, the solids are composed of three phases: aluminum hydroxide, silica, and the montmorillonite-like aluminosilicate. The difference in the local structure of Al and Si in the aluminosilicates was explained by the difference in interaction between the anions and aluminum ions. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Effect of a novel prolyl endopeptidase inhibitor, JTP-4819, on spatial memory and on cholinergic and peptidergic neurons in rats with ibotenate-induced lesions of the nucleus basalis magnocellularis.

We conducted behavioral and neurochemical studies of a novel prolyl endopeptidase inhibitor, (S)2-[[(S)-2-(hydroxyacetyl)-1pyrrolidinyl]carbonyl]-N-(phenylmeth yl)-1-pyrrolidine-carboxamide (JTP-4819), in rats with lesions of the nucleus basalis magnocellularis (NBM-lesioned rats) induced by ibotenate. Administration of JTP-4819 (1 and 3 mg/kg, p.o.), on and after the 8th day, significantly shortened the escape latency in the Morris water maze as compared to the vehicle-treated group. JTP-4819 also significantly increased the path length in the quadrant with the platform removed in the spatial probe trial. Neurochemical studies of brains removed after the Morris water maze task showed that choline acetyltransferase activity in the cerebral cortex, but not the hippocampus, was significantly reduced by NBM lesioning, while there were no changes of muscarinic M1 receptor binding activity detected using [3H]pirenzepine. JTP-4819 had almost no effect on these cholinergic parameters in NBM-lesioned rats. Substance P-like immunoreactivity (LI), thyrotropin-releasing hormone (TRH)-LI, and arginine-vasopressin-LI were not significantly changed in the cerebral cortex and hippocampus of NBM-lesioned rats as compared to sham-operated rats. However, these neuropeptide levels were significantly increased in both brain regions by repeated administration of JTP-4819 (1, 3 and/or 10 mg/kg, p.o.). These results suggest that JTP-4819 ameliorated memory impairment due to NBM lesioning by potentiating SP, TRH and AVPergic neurons secondary to PEP inhibition.

Animals↗
PubMed1999

Difference in security of stent jail between Palmaz-Schatz, NIR, and Multi-Link stents: the effect of balloon inflation through stent struts.

After placing a stent in the main vessel of a bifurcation lesion, it is often necessary to perform further balloon inflation or stent placement through the stent struts in order to treat a lesion of the secondary vessel or side branch. This balloon inflation with dilatation through the cells of the stent in the main vessel results in stent strut disfigurement. This disfigurement causes various degrees of stenosis within the main vessel secondary to stent strut deformity. The degree of strut deformity, and therefore stenosis, may vary significantly depending on stent design and structure. A model of a bifurcation lesion with an angle of 45 degrees was created from acrylic resin. The diameters of the main vessel and the secondary vessel were both 3.5 mm. Deployment of the Palmaz-Schatz stent (PS, n = 5), NIR stent (n = 5), or Multi-Link stent (n = 5) was performed in the main vessel with a 3.5-mm balloon catheter inflated to 6 atm. A second 3.5-mm balloon catheter was then inflated to 6 atm through the stent struts of the main vessel and into the ostium of the secondary vessel. The minimal lumen diameter (MLD) and cross-sectional area (CSA) at the ostium of the side branch and the stenosis within the main vessel were then measured, taking into account the stent deformity that occurred. Kissing balloon dilatation with two 3.5-mm balloon catheters was then performed and the stenosis secondary to stent deformity in the main vessel was remeasured. The MLD of the Multi-Link stent at the side-branch ostium was greater compared with those of the Palmaz-Schatz stent or the NIR stent (2.4 +/- 0.1, 1.6 +/- 0.1, 1.7 +/- 0.1 mm, P < 0.01) and CSA (4.9 +/- 0.5, 2.7 +/- 0.3, 2.5 +/- 0.3 mm(2), P < 0.01). Balloon inflation through the stent struts caused stent deformity that resulted in some degree of stenosis within the stent of the main vessel in all three stent types. Kissing balloon inflation reduced, but never eliminated, this stenosis. The percent stenosis in the main vessel secondary to stent deformity (PS 34% +/- 9%, NIR 25% +/- 8%, Multi-Link 34% +/- 7%, NS) and residual stenosis postkissing balloon inflation (PS 12% +/- 1%, NIR 10% +/- 3%, Multi-Link 14% +/- 3%, NS) were not significantly different among these three stents. At the side-branch ostium, the MLD and CSA were significantly greater for the Multi-Link stent compared with those of the Palmaz-Schatz or NIR stent. Balloon inflation through the stent struts caused stent deformity that resulted in stenosis within the stent in the main vessel. Kissing balloon inflation reduced this stenosis, but some residual stenosis always remained. The stenoses within the main vessel did not differ among the three stent types. Cathet. Cardiovasc. Intervent. 48:230-234, 1999.

Angioplasty, Balloon, Coronary↗
PubMed1999

Detection of IgA, IgM, and IgG subclasses of anti-M2 antibody by immunoblotting in autoimmune cholangitis: is autoimmune cholangitis an early stage of primary biliary cirrhosis?

Autoimmune cholangitis (AIC) has been proposed as a distinct disease entity from primary biliary cirrhosis (PBC), without antimitochondrial antibody (AMA) and anti-M2 antibody but with a high titer of antinuclear antibody (ANA) in the serum. However, negativity for AMA and anti-M2 antibody was determined by different methods in different studies. We hypothesized that anti-M2 antibody negativity in AIC resulted from methodological differences, including selection of the immunoglobulin subclass of the autoantibody. Twenty-three patients compatible with AIC whose serum tested negative for AMA and positive for ANA (> or = 1:80) were compared with 71 AMA-positive PBC patients. Laboratory findings, histology, and the pattern of anti-M2 antibody assessed by immunoblotting were compared. Alkaline phosphatase, total bilirubin, total cholesterol, and IgM values were lower in patients with AIC (P < 0.05, 0.01, respectively). Anti-smooth muscle antibody was detected more frequently in patients with AIC (P < 0.01). However, anti-M2 antibody was detected using immunoblotting not only in PBC but also in AIC cases. IgA class alone, IgM class alone, or both IgA and IgM classes of anti-M2 antibody were detected in 13%, 17%, and 22% of AIC patients, respectively, whereas they were not detected in PBC patients (P < 0.05, P < 0.01, P < 0.01). IgG class anti-M2 was detected in all patients with PBC, whereas it was detected in 48% of patients with AIC (P < 0.01). Histological evaluation showed that the early stages of disease were found more frequently in AIC (78%) than in PBC patients (39%) (P < 0.01). Anti-M2 antibody was detected by immunoblotting in all AIC patients. Hence, AIC is not a distinct disease from PBC. For diagnosing AIC and/or PBC, anti-M2 antibody should be examined by the immunoblotting assay to detect not only IgG but also IgA and IgM subclasses.

Adult↗
PubMed1999

A novel method for indexing echocardiographic left ventricular mass in infants, children and adolescents: evaluation of obesity-induced left ventricular hypertrophy.

BACKGROUND: Measurement of left ventricular mass (LVM) is important to the diagnosis of left ventricular hypertrophy in children with various cardiovascular diseases. The purpose of this study was to determine the most appropriate method for standardization of LVM and to evaluate obesity-induced left ventricular hypertrophy in children across the entire age range, from infancy through adolescence. METHODS: We studied 928 children and adolescents (527 males, 401 females), aged 0-17 years, who were classified into two groups by degree of obesity. Left ventricular mass was calculated by M-mode echocardiography using the formula of Devereux et al. and was indexed using body size (body length, bodyweight or body surface area) raised to a non-integer power using logarithmic transformation of measurements in children without obesity. RESULTS: The body length, bodyweight and body surface area exponents were 1.85, 0.88 and 1.15, respectively, in males, and 1.72, 0.82 and 1.08, respectively, in females. Whereas indexing of left ventricular mass by body length both in males and in females revealed significant differences between the two groups, indexing using bodyweight or body surface area exponents did not manifest left ventricular hypertrophy induced by obesity. CONCLUSION: It is suggested that applying body length exponents 1.85 in males and 1.72 in females is an appropriate method for indexation of LVM in children and adolescents. This method is particularly useful for the evaluation of left ventricular hypertrophy in children.

Adolescent↗
PubMed1999

Effect of mechanical strain on gastric cellular migration and proliferation during mucosal healing: role of Rho dependent and Rac dependent cytoskeletal reorganisation.

BACKGROUND: Various factors affect gastric wound healing. The influence of physical stimulation on gastric mucosal cells during the process of gastric wound healing is not completely understood. AIMS: To assess the role of a physical stimulant, in this case mechanical strain, on gastric mucosal restoration. METHODS: Mechanical strain was applied to adherent rat gastric mucosal cells (RGM1) cultured confluently on collagen type I coated silicone elastomer membrane in order to increase the dimension by an average of 5% and 10% at 5 cycles/minute for 72 hours after wounding. Repair of the wound was monitored every 12 hours for up to 72 hours using an inverted phase contrast microscope. Cell proliferation was detected using 5-bromodeoxyuridine staining. The cytoskeletal protein actin, a component of focal adhesion plaque protein, vinculin, and the small GTP-binding proteins RhoA and Rac1 were detected by immunohistochemistry in the cells located at the margin of and remote from the wound. RESULTS: The cells located at the margin of the wound showed the greatest migration and proliferation and were found to express more rudimentary lamellipodia and filopodia in the absence of mechanical strain. Vinculin, RhoA, and Rac1 were also strongly expressed in the wound margin. Under conditions of mechanical strain, the speed of migration of cells slowed and fewer proliferating cells were detected around the wound in a strain strength dependent manner. Lamellipodial formation, vinculin, RhoA, and Rac1 were poorly expressed in the same area. However, in cells located more than 1 mm from the wound edge, cytoskeletal rearrangement, and the expression of vinculin, RhoA, and Rac1 were not influenced by mechanical strain. CONCLUSIONS: Migration and proliferation of RGM1 cells in culture during wound healing were inhibited by mechanical strain, which caused dysfunction of the cytoskeletal and cell adhesion systems. It is suggested that physical stimulants such as mechanical strain may play a role in gastric wound healing in vivo by modifying cellular migration and proliferation.

Animals↗
PubMed1999

Tumor necrosis factor-alpha and interferon-gamma suppress both gene expression and deoxyribonucleic acid-binding of TTF-2 in FRTL-5 cells.

Tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) are cytokines that can individually or additively suppress thyroid cell function and the expression of thyroid-specific genes, such as thyroglobulin (TG) and thyroperoxidase (TPO). Thyroid transcription factor-2 (TTF-2) is a DNA-binding protein that modulates the expression of TG and TPO genes. In the present study, we examine the effects of TNF-alpha and IFN-gamma on TTF-2 gene expression, as well as the DNA-binding activity of TTF-2. FRTL-5 cells were maintained in 5H medium containing 0.2% calf serum for 7 days, then incubated with TNF-alpha, IFN-gamma, or TNF-alpha plus IFN-gamma. Total RNA was isolated and Northern blotted. TNF-alpha (50 ng/ml) only slightly suppressed (61+/-2% compared with control), whereas IFN-gamma (100 U/ml) modestly decreased TTF-2 messenger RNA (mRNA) levels (34+/-4%). TNF-alpha and IFN-gamma simultaneously caused a marked decrease in TTF-2 mRNA levels (13+/-2%). The suppressive effects of TNF-alpha and IFN-gamma on TTF-2 mRNA levels were concentration dependent and maximal at 50 ng/ml TNF-alpha with 100 U/ml IFN-gamma. The suppressive effect was also time dependent, reaching a maximum 12 h after exposure. Moreover, the suppressive effects of TNF-alpha and IFN-gamma upon rat TG and TTF-2 mRNA levels were similar. To test whether TNF-alpha and IFN-gamma alter TTF-2-binding to DNA, we performed electrophoretic mobility shift assays using a TTF-2-binding element in the rat TG gene as a probe. Formation of the TTF-2/DNA complex was decreased by TNF-alpha and/or IFN-gamma. Our results demonstrate that TNF-alpha and IFN-gamma additively reduce the gene expression and DNA-binding of TTF-2. These data suggest that TTF-2 is involved in the TNF-alpha and IFN-gamma-induced suppression of thyroid-specific gene expression.

Animals↗
PubMed1999

Coronary dissection due to overdilatation of an elastic membrane of the multi-link stent delivery system caused by balloon rupture.

A 65-year-old male with unstable angina underwent coronary angiography, which revealed a significant stenotic lesion in the right coronary artery. This narrowing was subsequently treated with the Multi-Link stent. During the balloon inflation associated with stent deployment, balloon rupture occurred and resulted in overdilatation of an elastic membrane in the stent delivery system. This, in turn, resulted in coronary dissection, which required treatment with further stenting.

Aged↗