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Biomedical subjects

M Kuwahara

Publications and source records attributed to M Kuwahara.

At least 19 recordsLinked to original sources
PubMed2006

Association between PADI4 and rheumatoid arthritis: a meta-analysis.

OBJECTIVE: Polymorphisms and haplotypes of the peptidylarginine deiminase type 4 gene (PADI4) have been reported to be associated with rheumatoid arthritis (RA) in a Japanese population. However, subsequent replication studies showed conflicting results. The aim of this study was to determine whether meta-analysis would prove the existence of the association. METHODS: PubMed was searched using the term 'PADI4' for articles from the publication of the first study to December 2005. Replication studies that tested the association between PADI4 and RA were reviewed for meta-analysis. The Breslow-Day test for homogeneity across the studies was calculated. The Mantel-Haenszel procedure was used to pool odds ratios (OR) with 95% confidence intervals (CI) to evaluate the association. RESULTS: Six replication studies, one from Japan and five from Europe and North America, fulfilled the selection criteria for inclusion in the meta-analysis. Homogeneity was confirmed across the replication studies. The common OR was 1.14 (95% CI = 1.07-1.21) for allelic distribution. The association was confirmed when only five replication studies in the European descent populations were combined (P = 0.0096, common OR = 1.10). CONCLUSIONS: Our meta-analysis showed a positive association between PADI4 and RA not only in the Japanese population but also in populations of European descent.

Arthritis, Rheumatoid↗
PubMed2005

Unconstrained cardiorespiratory and body movement monitoring system for home care.

An unconstrained respiratory rate (RR) and heart rate (HR) monitoring system to be used during sleeping is proposed. The system consisted of eight polyvinylidene fluoride cable sensors, charge amplifiers and measuring software, together with an analogue-to-digital converter unit. The cable sensors were horizontally embedded into a textile sheet on a bed surface covering the upper half of the body. The digital infinite impulse response filters were constructed to extract cardiorespiratory signals from displacement of the sensors. The system software automatically searched the optimum sensor(s) based on the power of the respective filter outputs. Then, the system obtained the 5 s average HR and 15 s average RR by measuring the intervals between the peaks of the respective autocorrelation functions of the filtered output. If the subject changed his posture, the system captured the image of the body position as a time stamp using a CCD camera. To show the validity of this method, the HR and RR obtained by this monitor were compared with those simultaneously measured using respiratory flow and an electrocardiogram. The results showed that the mean frame-by-frame difference ranged from -1.2 to 0.2 beats min(-1) for the HR and, for RR, ranged from -0.8 to 1.4 breath min(-1) during the short-term recordings. Similar differences were obtained during the first 2 h of overnight recordings. The proposed system is feasible for the combined long-term monitoring of a person's RR and HR with sleep posture changes and may be helpful for practical use in the home.

Adult↗
PubMed2004

Production and induction of manganese peroxidase isozymes in a white-rot fungus Pleurotus ostreatus.

The production of MnP by Pleurotus ostreatus in different liquid cultures was investigated. The highest level of activity was observed after 8 days of culture in peptone-glucose-yeast extract medium (PGY), whereas maximal activity was achieved after 30 days in glucose-yeast extract medium (GY). MnP was purified to homogeneity from PGY (designated MnP-PGY) and GY (MnP-GY). The isoelectric points of MnP-PGY and MnP-GY were 3.77 and 4.06, respectively. The molecular mass of both enzymes was 42 kDa. Analysis of the N-terminal amino acid sequence of purified MnPs and nucleotide sequence of cloned mnp indicated that MnP-GY has VTCATGQTTANE at the N-terminus, whereas MnP-PGY has ATCADGRTTANA. A putative exposed tryptophan residue (W170) was found in MnP-GY. Both isozymes oxidized veratryl alcohol, although the K(m) of MnP-GY was lower than that of MnP-PGY. Thus, the presence of peptone in the medium affected the production of MnP isozymes. Reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that the synthesis of MnP isozymes is controlled by culture conditions at the transcriptional level.

Amino Acid Sequence↗
PubMed2004

In vitro organogenesis of gut-like structures from mouse embryonic stem cells.

Embryonic stem (ES) cells have pluripotency and give rise to many cell types and tissues, including representatives of all three germ layers in the embryo. We have reported previously that mouse ES cells formed contracting gut-like organs from embryoid bodies (EBs). These gut-like structures contracted spontaneously, and had large lumens surrounded by three layers, i.e. epithelium, lamina propria and muscularis. Ganglia were scattered along the periphery, and interstitial cells of Cajal (ICC) were distributed among the smooth muscle cells. In the present study, to determine whether they can be a model of gut organogenesis, we investigated the formation process of the gut-like structures in comparison with embryonic gut development. As a result, we found that the fundamental process of formation in vitro was similar to embryonic gut development in vivo. The result indicates that the gut-like structure is a useful tool not only for developmental study to determine the factors that induce gut organogenesis, but also for studies of enteric neurone and ICC development.

Animals↗
PubMed2003

Daily use of dentifrice with and without xylitol and fluoride: effect on glucose retention in humans in vivo.

The effect of daily use of three different dentifrices on glucose retention after glucose mouth rinsing was tested in this study regarding xylitol and fluoride. Six experimental groups used three different dentifrices produced by two different companies: xylitol- and fluoride-containing dentifrice (XF), non-xylitol- and fluoride-containing dentifrice (F), and non-xylitol- and non-fluoride-containing dentifrice (NonX-NonF). Subjects were divided at random and rinsed their mouths for 15s with 20ml of 0.5M glucose solution. Glucose and lactate retention were determined by collecting samples of saliva from the approximal areas of the maxillary and mandibular anterior teeth and using the enzyme membrane test. Samples were collected 0, 1 and 2 months after the start of regular dentifrice use. There were significant differences in glucose retention in relation to the dentifrice used, month of sampling, site of sampling, and time since start of rinsing. Their contribution ratios were 2.0, 4.4, 11.7 and 7.4%, respectively (P<0.01). There were significant differences observed between the XF and NonX-NonF groups, with the XF group presenting lower glucose retention than the NonX-NonF group. The XF group presented lower glucose retention than the F group. The F group showed lower glucose retention than the NonX-NonF group. There were significant differences in lactate retention in relation to the month and site of sampling, and their contribution ratios were 3.3 and 2.8%, respectively (P<0.01). There were, however, no significant differences in glucose and lactate retention in relation to the dentifrice manufacturer. It was concluded that the XF dentifrice was the most effective, and the F dentifrice was more effective in reducing glucose retention than the NonX-NonF dentifrice.

Adult↗
PubMed2002

Impact of respiratory syncytial virus infection as a cause of lower respiratory tract infection in children younger than 3 years of age in Japan.

BACKGROUND: Respiratory syncytial virus (RSV) is the most important viral pathogen for lower respiratory tract infection (LRI) in infants and children. An RSV-specific monoclonal antibody has been developed to provide prophylaxis against RSV associated LRI (RSV-LRI). The objective of this study was to determine the impact of RSV as a cause of LRI in children younger than 3 years of age to provide data to aide in the implementation of forthcoming prophylaxis against RSV. METHODS: We analyzed the viral etiology of LRI in hospitalized Japanese children younger than 3 years of age admitted to Shizuoka Red Cross Hospital from July, 1997 to June, 2000. RESULTS: A total of 535 patients younger than 3 years of age were hospitalized with LRI at Shizuoka Red Cross Hospital from July 1, 1997 to June 30, 2000. Of these, a positive diagnosis of RSV infection was made in 168 patients (31.4%). Most of the patients with RSV infection had been well and had had no underlying disease that was defined as risk factor of RSV infection (94.0%). The peak incidence of LRI was observed in the winter each year and the number of LRI was strongly associated with the epidemic of RSV (r=0.700, P<0.0001). The number of patients with LRI younger than 6 months of age was 116 (21.7%). Of these 116 patients younger than 6 months with LRI, 55 patients (47.4%) were confirmed to have RSV infection. The proportions of RSV infection to total LRI was greatest in early infants younger than 6 months (P<0.0001). The number of patients with which RSV infection was detected in LRI patients younger than 3 years was highest during the first five months of life and there was a dramatic decrease in incidence of RSV infection with increasing age thereafter. CONCLUSIONS: The incidence of LRI hospitalization is highly affected by RSV infection epidemic. The proportion of RSV infections among early infants younger than 6 months is greater than that of older patients. The prophylaxis against RSV will be needed to be toward early infants.

Age Factors↗
PubMed2002

Use of facial artery musculomucosal flap for closure of soft tissue defects of the mandibular vestibule.

We present the use of the inferiorly based facial artery musculomucous (FAMM) flap to repair a defect of the mandibular vestibule, and discuss the advantages and disadvantages of this procedure. The FAMM flap an effectively cover defects of the mandibular vestibule and other regions of the oral cavity, and its softness, toughness, and minimal shrinkage allow for the use of dental prostheses.

Arteries↗
PubMed2001

Role of autonomic nervous system for development and suppression of motion sickness in Suncus murinus.

To clarify the role of autonomic nervous function in motion sickness, the effect of agents that act on the autonomic nervous system on the motion stimuli-induced emesis was studied in two strains of Suncus murinus (Jic:SUN-Her and Jic:SUN-Ler) with congenitally different sensitivity to veratrine sulfate. We demonstrated significant differences between the two strains in sensitivity to motion stimuli. Isoproterenol (2.5 mg kg(-1), s.c.) significantly prolonged the latency to the first emetic episode induced by motion stimuli and significantly decreased the number of emetic episodes in Jic:SUN-Her suncus. Hexamethoium (2.0 mg kg(-1), s.c.) tended to shorten the latency in Jic:SUN-Ler. Acetylcholine (1.2 mg kg(-1), s.c.) enhanced the emetic response in Jic:SUN-Ler, but atropine (4.0 mg kg(-1), s.c.) suppressed motion stimuli-induced emetic response in Jic:SUN-Her. These results suggest that the predominance of parasympathetic nervous activity is relevant to the enhancement of motion stimuli-induced emetic response, whereas the predominance of sympathetic nervous activity suppresses motion stimuli-induced emetic response. Norepinephrine (0.8 mg kg(-1), s.c.) enhanced motion stimuli-induced emesis contrary to isoproterenol in Jic:SUN-Ler although both drugs are adrenergic agents. However, atropine pretreatment (4.0 mg kg(-1), s.c.) inhibits norepinephrine-induced emetic response. It was considered that norepinephrine-induced emetic response might be dependent on a secondary increase of parasympathetic nervous activity due to bororeflex. Moreover, the different emetic response in Jic:SUN-Her and Jic:SUN-Ler suncus to motion stimuli and drug administration mentioned above indicated that different participation of autonomic nervous activity and/or afferent information from the baroreceptor in the emetic response may exist between these animal groups.

Acetylcholine↗
PubMed2001

Three families with autosomal dominant nephrogenic diabetes insipidus caused by aquaporin-2 mutations in the C-terminus.

The vasopressin-regulated water channel aquaporin-2 (AQP2) is known to tetramerize in the apical membrane of the renal tubular cells and contributes to urine concentration. We identified three novel mutations, each in a single allele of exon 4 of the AQP2 gene, in three families showing autosomal dominant nephrogenic diabetes insipidus (NDI). These mutations were found in the C-terminus of AQP2: a deletion of G at nucleotide 721 (721 delG), a deletion of 10 nucleotides starting at nucleotide 763 (763-772del), and a deletion of 7 nucleotides starting at nucleotide 812 (812-818del). The wild-type AQP2 is predicted to be a 271-amino acid protein, whereas these mutant genes are predicted to encode proteins that are 330-333 amino acids in length, because of the frameshift mutations. Interestingly, these three mutant AQP2s shared the same C-terminal tail of 61 amino acids. In Xenopus oocytes injected with mutant AQP2 cRNAs, the osmotic water permeability (Pf) was much smaller than that of oocytes with the AQP2 wild-type (14%-17%). Immunoblot analysis of the lysates of the oocytes expressing the mutant AQP2s detected a band at 34 kD, whereas the immunoblot of the plasma-membrane fractions of the oocytes and immunocytochemistry failed to show a significant surface expression, suggesting a defect in trafficking of these mutant proteins. Furthermore, coinjection of wild-type cRNAs with mutant cRNAs markedly decreased the oocyte Pf in parallel with the surface expression of the wild-type AQP2. Immunoprecipitation with antibodies against wild-type and mutant AQP2 indicated the formation of mixed oligomers composed of wild-type and mutant AQP2 monomers. Our results suggest that the trafficking of mutant AQP2 is impaired because of elongation of the C-terminal tail, and the dominant-negative effect is attributed to oligomerization of the wild-type and mutant AQP2s. Segregation of the mutations in the C-terminus of AQP2 with dominant-type NDI underlies the importance of this domain in the intracellular trafficking of AQP2.

Amino Acid Sequence↗
PubMed2001

Hybridization between oxy-peptide nucleic acids and DNAs: dependence of hybrid stabilities on the chain-lengths, types of base pairs, and the chain directions.

Oxy-peptide nucleic acids (OPNAs) of [-NH-CH(CH2-CH2-Base)-CH2-O-CH2-CO-]-type main chain with four different types of nucleobases (Base = A, G, C, and U) or with an abasic side group (X) were synthesized. Melting curves of the 1:1 hybrids of o(A(n))-d(Tn)) pairs with n = 6, 9, 12, and 15 showed very sharp transitions at high Tm values, particularly for long chains, indicating that nearly optimum matching is attained in the structure of the o(A(n))-d(Tn) hybrids. Effect of different types of base pairs on the hybrid stabilities was examined for the o(A4NA4)-d(T4N'T4) 1:1 mixtures where N is A, G, C, U, or X and N' is A, G, C, or T. In all series of the hybrids the complementary pairs showed the highest Tm values. The Tm values of the complementary pairs were about 35 degrees C when purine bases were inserted as the N group in the OPNA, but they were 20-23 degrees C when pyrimidine bases were inserted. The melting curves of the hybrids with a single mismatch were similar to those with a single X-N' pair, suggesting that the mismatch base pairs have been ignored in the hybrids. All complementary OPNA-DNA hybrids showed higher Tm values and sharper transitions than the corresponding DNA-DNA hybrids. The OPNA-DNA hybrids favor a parallel direction i.e., the N-terminal of OPNA is directed to the 5'-terminal of DNA.

Base Pairing↗
PubMed2001

Leukotriene D(4)-induced Rho-mediated actin reorganization in human bronchial smooth muscle cells.

We investigated the role of cysteinyl leukotriene (CysLT) receptors on leukotriene D(4)-induced actin reorganization and the signaling pathways of the response in human bronchial smooth muscle cells. The effects of leukotriene D(4) on actin reorganization in human bronchial smooth muscle cells were evaluated by dual-fluorescence labeling of filamentous (F) and monomeric (G) actin with fluorescein isothiocyanate (FITC)-labeled phalloidin and Texas Red-labeled DNase I, respectively. Leukotriene D(4) (100 nM) induced actin reorganization in the presence and absence of extracellular Ca(2+). The CysLT type 1 (CysLT(1)) receptor antagonist ONO 1078 (4-oxo-8(-)[p-(4-phenylbutyloxy) benzoylamino]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate) inhibited leukotriene D(4)-induced actin reorganization. Pretreatment with pertussis toxin, C3 exoenzyme, or tyrosine kinase inhibitors significantly reduced leukotriene D(4)-induced actin reorganization. However, phosphatidylinositol-3-kinase and protein kinase C inhibitors had little effect on these responses. These results suggest that leukotriene D(4)-induced actin reorganization in human bronchial smooth muscle cells is extremely dependent on the CysLT(1) receptor coupled with pertussis toxin-sensitive G protein, Rho GTPases and tyrosine phosphorylation pathways.

ADP Ribose Transferases↗
PubMed2001

The difference in E-cadherin expression between nonvascularized and vascularized nerve grafts: study in the rat sciatic nerve model.

BACKGROUND: We investigated the expression of E-cadherin during nerve regeneration after nonvascularized and vascularized nerve grafts. MATERIALS AND METHODS: We used the rat sciatic nerve model. E-cadherin expression was detected by Western blot analysis and immunofluorescent staining with anti E-cadherin monoclonal antibody. The level of E-cadherin expression was calculated as the amount relative to that of E-cadherin expression of normal control nerve. Furthermore, repair of the neural tissue structure was examined by toluidine blue staining. RESULTS: In both cases, the level of E-cadherin expression decreased at first, and then gradually increased. The maximum level was 1.61 +/- 0.066-fold in the nonvascularized nerve graft and 2.254 +/- 0.071-fold in the vascularized nerve graft. From the 1st to the 16th postoperative weeks, the level of E-cadherin expression in the vascularized nerve graft was significantly higher than that in the nonvascularized nerve graft. In the immunofluorescent staining, E-cadherin expression was almost negative or decreased immediately after the operation, but the degree of expression was gradually increased in Schwann cells. The degree of E-cadherin expression in the vascularized nerve graft was greater than that in the nonvascularized nerve graft. In toluidine blue staining, the velocity of tissue repair was more rapid in the vascularized nerve graft than in the nonvascularized graft. CONCLUSION: These results demonstrate that the E-cadherin expression of grafted nerve was increased during the nerve regeneration, and the expression was mainly observed in Schwann cells. Because the level of E-cadherin expression was significantly higher in the vascularized nerve graft than in the nonvascularized nerve graft, the level of E-cadherin expression may affect the rapidity of nerve regeneration.

Animals↗
PubMed2001

Efficient transformation of filamentous fungus Pleurotus ostreatus using single-strand carrier DNA.

The effects of carrier DNAs on the transformation of the basidiomycete Pleurotus ostreatus were analyzed. When lambda phage DNA was added to a transformation mixture containing protoplasts and CbxR vector plasmid, an increased number of drug-resistant transformants was observed on a screening plate containing 2 microg carboxin/ml. The highest efficiency (about 200 transformants/microg vector plasmid) was obtained by the addition of heat-denatured lambda DNA, which gave yields approximately 50-fold higher than the control experiment without a carrier DNA. To our knowledge, this is the first report on enhancement in transformation efficiency of fungal protoplasts by single strand carrier DNA.

Bacteriophage lambda↗
PubMed2001

Homologous expression of recombinant manganese peroxidase genes in ligninolytic fungus Pleurotus ostreatus.

Pleurotus ostreatus is a white-rot fungus known as an efficient degrader of lignin and also various organo-pollutants. Using a DNA-mediated transformation system, a molecular breeding approach to isolate over-producers of a manganese peroxidase isozyme, MnP3, was carried out. Recombinant mnp3 constructs under the control of P. ostreatus sdi1 expression signals were introduced into the wild-type P. ostreatus strain by co-transformation with a carboxin-resistant vector plasmid, pTM1. One of the recombinants obtained by a mating between two monokaryotic transformants, TMG9-C1, showed a several times higher level of MnP activity than the wild-type control in the early stage of liquid culture. Predominant transcription of the recombinant mnp3 in the strain was demonstrated by RT-PCR experiments. This is the first report of a genetically modified P. ostreatus strain with an expression system for recombinant genes.

Base Sequence↗
PubMed2001

Stable transformation of Pleurotus ostreatus to hygromycin B resistance using Lentinus edodes GPD expression signals.

It was reported that Pleurotus ostreatus was transformed unstably using recombinant plasmids containing a hygromycin B phosphotransferase gene (hph) under the control of Aspergillus nidulans expression signals, and that the plasmids were maintained extrachromosomally in the transformants. Here we report a stable and integrative transformation of the fungus to hygromycin B resistance, using a recombinant hph fused with Lentinus edodes glyceraldehyde-3-phosphate dehydrogenase expression signals. Restriction-enzyme-mediated integration (REMI) was also tried and increased the transformation efficiency about ten-fold.

Anti-Bacterial Agents↗
PubMed2001

Production of manganese peroxidase by pellet culture of the lignin-degrading basidiomycete, Pleurotus ostreatus.

Pleurotus ostreatus No. 42 produced the ligninolytic enzymes, manganese peroxidase (MnP) and laccase, in agitation culture in glucose/peptone/wheat-bran medium. Formation of mycelial pellets 1-2 mm in diameter was essential for the production of MnP; and the concentration of dissolved oxygen in the culture medium greatly influenced the production of MnP, a concentration over 5 ppm being necessary for MnP production. The maximal activity of MnP was obtained on days 7-9 of culture, after the consumption of nutrient glucose. Introduction of oxygen from the start of the cultivation caused large pellet formation, which resulted in a low MnP activity level. P. ostreatus No. 42 produced two MnP isozymes in agitation culture. The major isozyme, F-2, was 36.4 kDa and had a pI of 3.95. The MnP characteristics, Km values, dependence on Mn2+ and optimum pH showed the similarity between this isozyme and MnP 3, which was produced under different culture conditions. Analysis of the N-terminal amino acid sequence indicated the close similarity of F-2 to MnP 3.

Amino Acid Sequence↗