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H Miura

Publications and source records attributed to H Miura.

At least 19 recordsLinked to original sources
PubMed2006

Association study between kynurenine 3-monooxygenase gene and schizophrenia in the Japanese population.

Several lines of evidence suggest that metabolic changes in the kynurenic acid (KYNA) pathway are related to the etiology of schizophrenia. The inhibitor of kynurenine 3-monooxygenase (KMO) is known to increase KYNA levels, and the KMO gene is located in the chromosome region associated with schizophrenia, 1q42-q44. Single-marker and haplotype analyses for 6-tag single nucleotide polymorphisms (SNPs) of KMO were performed (cases = 465, controls = 440). Significant association of rs2275163 with schizophrenia was observed by single-marker comparisons (P = 0.032) and haplotype analysis including this SNP (P = 0.0049). Significant association of rs2275163 and haplotype was not replicated using a second, independent set of samples (cases = 480, controls = 448) (P = 0.706 and P = 0.689, respectively). These results suggest that the KMO is unlikely to be related to the development of schizophrenia in Japanese.

Aged↗
PubMed2006

Colonisation on the tongue surface by respiratory pathogens in residents of a nursing home--a pilot study.

OBJECTIVE: The morbidity and mortality of the dependent elderly that result from aspiration pneumonia have been recognised as a major geriatric health problem. The tongue has an extremely large surface area and due to its papillary structure can retain considerable quantities of food, and thus can support and harbour a large bacterial population. The purpose of this study was to gain more information on the microflora of the tongue surface and to assess the existence of oral infectious pathogens potentially causing respiratory disease in nursing home residents. SUBJECTS AND METHODS: The tongue bacterial flora of 69 nursing home residents were examined to identify microorganisms by the culture method. RESULTS: Thirteen species of microorganisms were detected from the tongue in this study. In 41 of 69 subjects (59%), potential respiratory pathogens, had colonised the tongue surface. CONCLUSION: The results of the present study revealed that bacteria that commonly cause respiratory infection colonised the tongue of nursing home residents, suggesting that it may function as a reservoir of potential respiratory pathogens to facilitate colonisation on the oropharynx.

Aged↗
PubMed2005

Mapping QTLs for grain dormancy on wheat chromosome 3A and the group 4 chromosomes, and their combined effect.

A major QTL for grain dormancy, QPhs.ocs-3A.1, derived from the highly dormant wheat Zenkoujikomugi (Zen), has been identified in a study made under a controlled environment. Further investigations were needed to dissect the precise position and expression of QPhs.ocs-3A.1 under different field conditions because the ability to detect genetic loci for grain dormancy traits is compromised by environmental effects and genotype/environment interactions. Group 4 chromosomes have also been shown to be possible sites of QTLs for grain dormancy. The objectives of this study were (1) to locate additional molecular markers in the QPhs.ocs-3A.1 region, (2) to identify QTLs on the group 4 chromosomes and (3) to elucidate their combined effects. We examined the recombinant inbred lines (RILs) from a cross between Chinese Spring (CS) and Zen over a 3-year period in one location and 1 year in a different location. In an interval mapping study QPhs.ocs-3A.1 was mapped to within the 4.6 cM region flanked by Xbarc310 and Xbcd907 at the proximal end of the short arm of chromosome 3A. QPhs.ocs-3A.1 was confirmed to be the predominant dormancy QTL since it explained a large portion (11.6-44.8%) of the phenotypic variation, and was strongly displayed under dormancy-breaking conditions or at low germination temperatures. For QPhs.ocs-4A.1, identified on the long arm of chromosome 4A, and QPhs.ocs-4B.1, on the centromeric region of the long arm of Chr 4B, the LOD peak positions and the desirable allele were consistent between the trials, while the LOD scores and contribution to the phenotypic variation varied. Transgressive segregants were observed among the 125 RILs and most of them had a combination of the three alleles conferring a higher dormancy: the Zen alleles at QPhs.ocs-3A.1 and QPhs.ocs-4A.1 and the CS allele at QPhs.ocs-4B1. This demonstrated a combined effect of the desirable alleles on accelerating grain dormancy, with their total effect being superior to that of Zen.

Chromosome Mapping↗
PubMed2005

Effects of fluvoxamine on levels of dopamine, serotonin, and their metabolites in the hippocampus elicited by isolation housing and novelty stress in adult rats.

The authors investigated the effects of fluvoxamine on neurochemical changes in the hippocampus elicited by isolation housing and novelty stress. Male F344 rats (11 w) were housed one per cage for four weeks. On each day of the last week (7 days) they were s.c. injected with fluvoxamine (20 mg/kg), and then subjected to novelty stress. Isolation housing significantly increased dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) levels, whereas fluvoxamine significantly decreased them. Isolation housing significantly increased the DOPAC/DA ratio. Fluvoxamine significantly decreased the DA level, and partially restored the DOPAC and 5-HIAA levels increased by isolation housing.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2005

Adhesion to root canal dentine using one and two-step adhesives with dual-cure composite core materials.

The regional tensile bond strengths of two dual-cure composite resin core materials to root canal dentine using either a one or two-step self-etching adhesive were evaluated. Extracted premolar teeth were decoronated and their root canals prepared to a depth of 8 mm and a width of 1.4 mm. In one group, a one-step self-etching adhesive (Unifil Self-etching Bond) was applied to the walls of the post-space and light-cured for 10 s. After which, the post-spaces were filled with the a dual-cure composite resin (Unifil Core) and then half the specimens were light-cured for 60 s and the other half placed in darkness for 30 min. In the second group, a self-etching primer (ED Primer II) was applied for 30 s, followed by an adhesive resin (Clearfil Photo Bond), which was light-cured for 10 s. The post-spaces were filled with a dual-cure composite resin (DC Core) and then half the specimens were light-cured for 60 s and the other half placed in darkness for 30 min. Chemical-cure composite resin was placed on the outer surfaces of all the roots, which were then stored in water for 24 h. They were serially sliced perpendicular to the bonded interface into 8, 0.6 mm-thick slabs, and then transversely sectioned into beams, approximately 8 x 0.6 x 0.6 mm, for the microtensile bond strength test (muTBS). Data were divided into two (coronal/apical half of post-space) and analysed using three-way anova and Scheffe's test (P < 0.05). Failure modes were observed under an scanning electron microscope (SEM) and statistically analysed. Specimens for observation of the bonded interfaces were prepared in a similar manner as for bond strength testing, cut in half and embedded in epoxy resin. They were then polished to a high gloss, gold sputter coated, and after argon ion etching, observed under an SEM. For both dual-cure composite resins and curing strategies, there were no significant differences in muTBS between the coronal and apical regions (P > 0.05). In addition, both dual-cure composite resins exhibited no significant differences in muTBS irrespective of whether polymerization was chemically or photoinitiated (P > 0.05). Both dual-cure composite resins exhibited good bonding to root canal dentin, which was not dependent upon region or mode of polymerization.

Bicuspid↗
PubMed2005

Validity of an oblique posterior condylar radiographic view for revision total knee arthroplasty.

We have previously developed a radiographic technique, the oblique posterior condylar view, for assessment of the posterior aspect of the femoral condyles after total knee arthroplasty. The purpose of this study was to confirm the validity of this radiographic view based upon intra-operative findings at revision total knee arthroplasty. Lateral and oblique posterior condylar views were performed for 11 knees prior to revision total knee arthroplasty, and radiolucent lines or osteolysis of the posterior aspect of the femoral condyles were identified. These findings were compared with the intra-operative appearance of the posterior aspects of the femoral condyles. Statistical analysis showed that sensitivity and efficacy were significantly better for the oblique posterior condylar than the lateral view. This method can, therefore, be considered as suitable for routine follow-up radiographs of the femoral component and in the pre-operative planning of revision surgery.

Aged↗
PubMed2005

Contact stress at the post-cam mechanism in posterior-stabilised total knee arthroplasty.

We measured the contact areas and contact stresses at the post-cam mechanism of a posterior-stabilised total knee arthroplasty when a posterior force of 500 N was applied to the Kirschner Performance, Scorpio Superflex, NexGen LPS Flex Fixed, and NexGen LPS Flex Mobile knee systems. Measurements were made at 90 degrees, 120 degrees, and 150 degrees of flexion both in neutral rotation and 10 degrees of internal rotation of the tibial component. Peak contact stresses at 90 degrees, 120 degrees, and 150 degrees were 24.0, 33.9, and 28.8 MPa, respectively, for the Kirschner; 26.0, 32.4, and 22.1 MPa, respectively, for the Scorpio; and 34.1, 31.5, and 32.5 MPa, respectively, for the NexGen LPS Flex Fixed. With an internally rotated tibia, the contact stress increased significantly with all the fixed-bearing arthroplasties but not with the NexGen LPS Flex Mobile arthroplasty. The post-cam design should be modified in order to provide a larger contact area whilst avoiding any impingement and edge loading.

Arthroplasty, Replacement, Knee↗
PubMed2004

Fluvoxamine, a selective serotonin reuptake inhibitor, suppresses tetrahydrobiopterin levels and dopamine as well as serotonin turnover in the mesoprefrontal system of mice.

RATIONALE: Tetrahydrobiopterin (BH4) is a coenzyme of tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), rate-limiting enzymes of monoamine biosynthesis. According to the monoamine hypothesis of depression, antidepressants will restore the function of the brain monoaminergic system, and BH4 concentration. OBJECTIVE: To investigate the effects of fluvoxamine on BH4 levels and dopamine (DA) and serotonin (5-HT) turnover in the mesoprefrontal system, incorporating two risk factors of depression, social isolation and acute environmental change. METHODS: Male ddY mice (6W) were divided into two housing groups, i.e. group-housing (eight animals per cage; 35 days), and isolation-housing (one per cage; 35 days), SC injected with fluvoxamine (20 or 40 mg/kg; days 29-35), and exposed to 20-min novelty stress (day 35). The levels of BH4, DA, homovanilic acid (HVA), 5-HT, and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the prefrontal cortex and midbrain. RESULTS: Under the group-housing condition, novelty stress significantly increased BH4 levels in both regions, and the HVA/DA ratio in the midbrain, whereas it did not change any parameters in either region under the isolation-housing condition. In the prefrontal cortex, fluvoxamine significantly decreased the 5-HIAA/5-HT ratio under the group-housing condition, and BH4 levels and the HVA/DA ratio under the isolation-housing condition. In the midbrain, fluvoxamine significantly decreased all parameters, except for an increasing in the 5-HIAA/5-HT ratio under the isolation-housing condition. CONCLUSION: Isolation-housing suppressed the increase of BH4 levels and DA turnover elicited by novelty stress. Fluvoxamine suppressed BH4 levels, and DA and 5-HT turnover. Fluvoxamine may have altered DA turnover by suppressing BH4 levels.

Animals↗
PubMed2004

Comparative analysis of genetic diversity and expression of amoA in wastewater treatment processes.

The genetic diversity and expression of amoA of autotrophic ammonia oxidizers in wastewater treatment processes were investigated by RT-PCR and denaturing gradient gel electrophoresis (DGGE) in order to identify active components of ammonia-oxidizer populations in a such processes. Ammonia oxidizers, evidenced by the presence of amoA mRNA, were regarded as metabolically active. The DGGE profiles derived from amoA mRNA and from its gene, which were amplified by RT-PCR or PCR using samples collected from a bench-scale reactor treating high concentration of inorganic ammonia, were similar. In contrast, RNA and DNA-derived DGGE profiles from three domestic wastewater treatment facilities were different from each other. These data indicate that the dominant ammonia oxidizers in the bench-scale reactor exhibited ammonia-oxidizing activity, whereas some ammonia oxidizers in the domestic wastewater treatment facilities apparently did not express high levels of amoA mRNA.

Ammonia↗
PubMed2004

Fluvoxamine, a selective serotonin reuptake inhibitor, suppresses tetrahydrobiopterin in the mouse hippocampus.

In the present study, we investigated the effects of fluvoxamine, a selective serotonin reuptake inhibitor, on brain tetrahydrobiopterin (BH4) levels. We directly measured levels of BH4 by Tani and Ohno's direct method as well as the serotonin (5-HT) turnover ratio, i.e. 5-hydroxyindoleacetic acid (5-HIAA)/5-HT, after sub-acute s.c. injection of fluvoxamine in the hippocampus of mice. Our animal model incorporated two risk factors of depression, social isolation and acute environmental change. Male ddY mice (6W) were housed in isolation (1 per cage; 35 days), injected with fluvoxamine (20 or 40 mg/kg; days 29-35), and exposed to novelty stress (20 min; day 35). In the stress session, behavioral parameters, i.e. total distance and rearing behavior, were measured. Isolation housing increased both behaviors. Fluvoxamine attenuated rearing behavior, but did not influence total distance. Isolation housing increased BH4 levels. Novelty stress increased BH4 levels in group housing, although it did not change them in isolation housing. Fluvoxamine suppressed BH4 levels. In isolation housing, fluvoxamine increased 5-HT turnover ratios, while it decreased them in group housing. In conclusion, fluvoxamine, housing condition, and novelty stress regulated BH4 levels. Fluvoxamine may have changed behavior and 5-HT turnover by suppressing BH4 levels as well as by inhibiting 5-HT reuptake.

Animals↗
PubMed2004

Serial follow-up study of serum testosterone and antisperm antibodies in patients with non-obstructive azoospermia after conventional or microdissection testicular sperm extraction.

Testicular sperm extraction (TESE) combined with intracytoplasmic sperm injection is becoming a first-line treatment even for non-obstructive azoospermia. The current focus of TESE is the identification of seminiferous tubules that contain spermatozoa and minimization of testicular damage. Although microdissection TESE has been introduced as a preferred procedure for sperm retrieval, no serial follow-up studies of testicular damage have been reported. In the present study, we assayed serum testosterone concentrations and for the presence of antisperm antibodies (ASA) for 1 year after conventional multiple TESE or microdissection TESE and compared postoperative testicular damage between procedures. Thirteen patients who underwent conventional multiple TESE and 12 patients who underwent microdissection TESE were included in this study. Serum total and free testosterone concentrations were evaluated before operation and 1, 6 and 12 months after TESE. Serum ASA was also evaluated before and 12 months after TESE. Serum total and free testosterone concentrations in all patients in both groups showed no significant postoperative decrease. A comparison between the two groups of serum total and free testosterone concentrations showed no significant difference (total testosterone, p = 0.2477; free testosterone, p = 0.3098). No incidence of new ASA formation was identified in the present study. In conclusion, TESE procedures cause neither a decrease of serum testosterone nor formation of ASA. Serum testosterone concentration are similar between patients in the conventional multiple TESE and microdissection groups. Therefore, microdissection TESE is safe with respect to testicular damage, particularly for patients with hypogonadism.

Adult↗
PubMed2004

Metformin ameliorates treatment of obese type 2 diabetic patients with mental retardation; its effects on eating behavior and serum leptin levels.

The metabolic effects of a biguanide, metformin, on glycemic control and eating behavior were investigated in 16 type 2 diabetic subjects with mental retardation who were habitual overeaters and had difficulty in controlling their appetites. The subjects (n = 16) received metformin (750 mg/day) for 6 months and body weight, body mass index (BMI) were measured monthly. They had repetitive metabolic and hormonal studies. Their eating behavior was analyzed by questionnaires given by their guardians before and after treatment. Metformin treatment significantly reduced their body weights (p < 0.01), body mass index (BMI) (p < 0.01), the levels of HbA1c (p < 0.001), fasting blood glucose (FBG) (p < 0.05), serum insulin (p < 0.05), C-peptide (p < 0.01), triglyceride (p < 0.01), and total cholesterol (p < 0.05). Insulin resistance index (FBG (mg/dl) x serum insulin levels ( micro U/ml) x 1/405) was significantly reduced after 1-month treatment. The serum leptin levels were significantly decreased after 4 month's treatment and thereafter (p < 0.05). Analysis of the questionnaires before and after treatment showed that the daily intake of regular and additional foods significantly decreased after treatment (p < 0.01 and p < 0.001, respectively) with improvements of eating behavior. We conclude that metformin may have beneficial effects not only to control glycemia but also to correct eating behavior in obese type 2 diabetic patients with the difficulty in controlling their appetites. The improvement was related to the reduction of insulin resistance and serum leptin levels.

Adult↗
PubMed2004

Tracheal narrowing secondary to airway obstruction in two cats.

Tracheal narrowing is described in two cats. In both cases, inspiratory radiographs demonstrated tracheal narrowing just cranial to the thoracic inlet; no narrowing was seen on expiratory radiographs. Magnetic resonance imaging revealed suspected nasal tumours in both cases, but no abnormalities were identified in the region of the narrowed trachea. Nasal biopsy confirmed intranasal lymphoma in one cat and nasal adenocarcinoma in the other. The former cat was treated with chemotherapy. The owner of the latter cat declined further treatment. The tracheal narrowing disappeared after the initiation of chemotherapy in the cat with intranasal lymphoma and it is suggested that the narrowing might have been associated with the nasal tumour. A careful evaluation of the airway, especially cranial to the narrowing, is recommended in cases of tracheal narrowing in cats.

Adenocarcinoma↗
PubMed2004

Elasto-plastic contact analysis of an ultra-high molecular weight polyethylene tibial component based on geometrical measurement from a retrieved knee prosthesis.

The wear phenomenon of ultra-high molecular weight polyethylene (UHMWPE) in knee and hip prostheses is one of the major restriction factors on the longevity of these implants. Especially in retrieved knee prostheses with anatomical design, the predominant types of wear on UHMWPE tibial components are delamination and pitting. These fatigue wear patterns of UHMWPE are believed to result from repeated plastic deformation owing to high contact stresses. In this study, the elasto-plastic contact analysis of the UHWMPE tibial insert, based on geometrical measurement for retrieved knee prosthesis, was performed using the finite element method (FEM) to investigate the plastic deformation behaviour in the UHMWPE tibial component. The results suggest that the maximum plastic strain below the surface is closely related to subsurface crack initiation and delamination of the retrieved UHMWPE tibial component. The worn surface whose macroscopic geometrical congruity had been improved due to wear after joint replacement showed lower contact stress at macroscopic level.

Aged↗
PubMed2004

The accuracy of image-guided knee replacement based on computed tomography.

Our study evaluated the accuracy of an image-guided total knee replacement system based on CT with regard to preparation of the femoral and tibial bone using nine limbs from five cadavers. The accuracy was assessed by direct measurement using an extramedullary alignment rod without radiographs. The mean angular errors of the femur and tibia, which represent angular gaps from the real mechanical axis in the coronal plane, were 0.3 degrees and 1.1 degrees, respectively. The CT-based system, provided almost perfect alignment of the femoral component with less than 1 degrees of error and excellent alignment with less than 3 degrees of error for the tibial component. Our results suggest that standardisation of knee replacement by the use of this system will lead to improved long-term survival of total knee arthroplasty.

Arthroplasty, Replacement, Knee↗
PubMed2004

Changes in plasma ghrelin and growth hormone concentrations in mature Holstein cows and three-month-old calves.

We measured changes in plasma ghrelin and GH concentrations in mature Holstein cows and 3-mo-old female Holstein calves fed at scheduled times. Our objective was to determine the characteristics of ghrelin secretion in dairy cattle and its influence on GH. Animals were fed at 0800 and 1600 for 2 wk before and during experiments. Plasma was sampled for 24 h at 2-h intervals in Exp. 1. In mature cows, plasma ghrelin concentrations decreased (P < 0.01) just after 0800 but not at the 1600 feeding. Ghrelin concentrations were lower (P < 0.01) in calves than in mature cows and they did not decrease after feeding in calves. The temporal relationship between ghrelin and GH remained unclear. In Exp. 2, plasma was sampled 2 h before and after both morning and evening feedings at 20-min intervals. Plasma ghrelin concentrations decreased (P < 0.05) 40 min after 0800 feeding and 60 min after 1600 feeding in mature cows. These results indicate that in mature cows, plasma ghrelin concentration decreased after feeding, but this decrease was not evident in 3-mo-old calves. Further studies are required to define the relationship between plasma ghrelin and GH concentrations.

Age Factors↗
PubMed2003

Mapping QTLs for seed dormancy and the Vp1 homologue on chromosome 3A in wheat.

A major component of the observed genetic variation for pre-harvest sprouting in wheat ( Triticum aestivum L.) appears to be the level of seed dormancy. Group 3 chromosomes have received attention as carrying the R genes for seed-coat color and the taVp1 genes that are orthologous to the maize Vp1 gene which encode a dormancy-related transcription factor. The objectives of the present study were to map quantitative trait loci (QTLs) for seed dormancy on chromosome 3A and to investigate an association between taVp1 or R-A1 and the QTLs detected. A mapping population in the form of recombinant inbred lines developed from the cross between the highly dormant Zenkoujikomugi (Zen) and Chinese Spring (CS) was utilized. Nineteen marker loci, including taVp1, were mapped on chromosome 3A. The taVp1 locus was located in the middle of the long arm, about 85 cM from the centromere. The population was evaluated in duplicate by growing them under controlled environment conditions. Two QTLs for seed dormancy, designated as QPhs.ocs-3A.1 and QPhs.ocs-3A.2, were identified on the short and long arms, respectively. QPhs.ocs-1 explained 23-38% of the phenotypic variation and the Zen allele had a striking effect on maintaining dormancy. QPhs.ocs-2, with a minor effect, was detectable only at the dormancy-breaking stage. Although QPhs.ocs-2 was loosely linked to taVp1 by around 50 cM, they are clearly distinct genes. Zen and CS carry the white R-A1a allele, and no QTL effect was detected in the vicinity region of R-A1. Hence it was concluded that the high dormancy associated with chromosome 3A of Zen is ascribable to QPhs.ocs-1 on the short arm but is not due to the direct contribution of either the taVp1 or R-A1 locus.

Chromosomes, Plant↗