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M Nishida

Publications and source records attributed to M Nishida.

At least 19 recordsLinked to original sources
PubMed2006

Mitogenomic evolution and interrelationships of the Cypriniformes (Actinopterygii: Ostariophysi): the first evidence toward resolution of higher-level relationships of the world's largest freshwater fish clade based on 59 whole mitogenome sequences.

Fishes of the order Cypriniformes are almost completely restricted to freshwater bodies and number > 3400 species placed in 5 families, each with poorly defined subfamilies and/or tribes. The present study represents the first attempt toward resolution of the higher-level relationships of the world's largest freshwater-fish clade based on whole mitochondrial (mt) genome sequences from 53 cypriniforms (including 46 newly determined sequences) plus 6 outgroups. Unambiguously aligned, concatenated mt genome sequences (14,563 bp) were divided into 5 partitions (first, second, and third codon positions of the protein-coding genes, rRNA genes, and tRNA genes), and partitioned Bayesian analyses were conducted, with protein-coding genes being treated in 3 different manners (all positions included; third codon positions converted into purine [R] and pyrimidine [Y] [RY-coding]; third codon positions excluded). The resultant phylogenies strongly supported monophyly of the Cypriniformes as well as that of the families Cyprinidae, Catostomidae, and a clade comprising Balitoridae + Cobitidae, with the 2 latter loach families being reciprocally paraphyletic. Although all of the data sets yielded nearly identical tree topologies with regard to the shallower relationships, deeper relationships among the 4 major clades (the above 3 major clades plus Gyrinocheilidae, represented by a single species Gyrinocheilus aymonieri in this study), were incongruent depending on the data sets. Treatment of the rapidly saturated third codon-position transitions appeared to be a source of such incongruities, and we advocate that RY-coding, which takes only transversions into account, effectively removes this likely "noise" from the data set and avoids the apparent lack of signal by retaining all available positions in the data set.

Animals↗
PubMed2006

Human oviductal epithelial cells express Toll-like receptor 3 and respond to double-stranded RNA: Fallopian tube-specific mucosal immunity against viral infection.

BACKGROUND: The aim of this study was to evaluate the site-specific immunoregulatory mechanisms against viral infection in human Fallopian tubes. METHODS: We therefore investigated the effects of double-stranded RNA (dsRNA) on the production of interleukin (IL)-6, IL-8 and granulocyte chemotactic protein-2 (GCP-2) by cultured oviductal epithelial cells (OECs) using enzyme-linked immunosorbent assays. Phosphorylation of inhibitor kappaB-alpha (IkappaB-alpha) protein after dsRNA stimulation and the expression of Toll-like receptor (TLR) 3 in these cells were also evaluated by western blot analysis. RESULTS: Polyriboinosinic:polyribocytidylic acid (poly I:C), a synthetic dsRNA that antagonizes TLR3, stimulated the secretion of IL-6, IL-8 and GCP-2 by OECs. Poly I:C-induced production of these cytokines by OECs was inhibited by the pretreatment of these cells with anti-TLR3 antibody. The phosphorylation of IkappaB-alpha protein was detected in OECs after stimulation by poly I:C. The expression of TLR3 was also detected in OECs. CONCLUSION: These results suggest that the epithelial cells of the human Fallopian tube have evolved a unique, site-specific mechanism for recognizing viral infection. TLR3-mediated production of proinflammatory cytokines and chemokines in OECs in response to viral dsRNA may be important for antiviral immunity in the human female reproductive tract.

Adult↗
PubMed2006

Beta-hydroxyisovalerylshikonin induces apoptosis and G0/G1 cell-cycle arrest of endometriotic stromal cells: a preliminary in vitro study.

BACKGROUND: Most of the current medical treatments for endometriosis aim to down-regulate the estrogen activity. However, a high recurrence rate after medical treatments has been the most significant problem. Beta-hydroxyisovalerylshikonin (beta-HIVS) is an ATP non-competitive inhibitor of protein-tyrosine kinases and is considered an apoptosis-inducing agent. The aim of this study is to evaluate the effects of beta-HIVS on the proliferation, cell cycle and apoptosis of endometriotic stromal cells. METHODS: We investigated the effects of beta-HIVS on cultured ovarian endometriotic cyst stromal cells (ECSC) by a modified methylthiazoletetrazolium (MTT) assay, a 5-bromo-2'-deoxyuridine (BrdU) incorporation assay and internucleosomal DNA fragmentation assays. The effect of beta-HIVS on the cell cycle of ECSC was determined by flow cytometry. The expression of apoptosis-related molecules was examined in ECSC using western blot analysis. RESULTS: Beta-HIVS significantly inhibited the proliferation and DNA synthesis of ECSC and induced apoptosis and G0/G1 phase cell-cycle arrest of these cells. Down-regulation of the B-cell lymphoma/leukaemia-2 (Bcl-2) expression with the activation of caspase-3, caspase-8 and caspase-9 was observed in ECSC after beta-HIVS treatment. CONCLUSIONS: These results suggest that beta-HIVS induces apoptosis of ECSC by suppressing anti-apoptotic proteins. Although our present findings are preliminary, beta-HIVS could potentially be a therapeutic agent for the treatment of endometriosis.

Apoptosis↗
PubMed2006

High maneuverability guidewire with functionally graded properties using new superelastic alloys.

Nitinol shape memory alloys (SMAs) are attracting considerable attention as core materials for medical guidewires because of their excellent flexibility and shape retention. However, since Nitinol guidewires possess low rigidity, the pushability and torquability of the guidewires are insufficient. On the other hand, although guidewires made of stainless steel have high pushability, plastic deformation occurs easily. We have developed a new class of superelastic guidewires with functionally graded properties from the tip to the end by using new SMA core materials such as Cu-Al-Mn-based or Ni-free Ti-Mo-Sn SMAs. The tip portion of the guidewire shows excellent superelasticity (SE), while the body portion possesses high rigidity. These functionally graded characteristics can be realized by microstructural control. These guidewires with functionally graded properties show excellent pushability and torquability and are considerably easier to handle than conventional guidewires with Nitinol or stainless steel cores. Moreover, a metallic catheter using a Ni-free Ti-based SMA with high biocompatibility is introduced.

Alloys↗
PubMed2006

[Blunt right atrial rupture].

Atrial rupture without other major injury following blunt chest trauma is rare, but carries high mortality rate. Here we report 3 cases of blunt atrial rupture. All patients presented with hypotension and loss of consciousness. Echocardiography and computed tomography (CT) demonstrated pericardial effusion in all cases. All patients underwent surgery with a median sternotomy. Tear of the right atrium was seen in 2 patients, and no remarkable tear was seen in 1 patient. One of the 3 patients underwent surgery using cardiopulmonary bypass because he showed cardiogenic shock. Pericardiocentesis before the operation was not effective. All patients were discharged uneventfully. Echocardiography and CT were useful for diagnosis of cardiac rupture. In most reported cases, the cardiac tear has been repaired without using cardiopulmonary bypass. However, it is difficult to diagnose location of the tear, therefore, the repair became safer using cardiopulmonary bypass for the patients with cardiogenic shock. This article has described the mechanisms and generation of blunt chest trauma lesions.

Adult↗
PubMed2006

[Treatment for perioperative arrhythmias with nifekalant hydrochloride].

Ventricular tachycardia (VT), ventricular fibrillation (VF), and atrial flutter (AFL) are potentially fatal or serious complications arising after cardiac surgery. Generally, we treat these complications with class I antiarrhythmic agents and/or direct counter shock (DC). However, sometimes these complications do not respond to antiarrhythmic agents and require frequent DC. Moreover, these class I agents induce heart failure due to their negative inotropic effect. Nifekalant hydrochloride (NIF) is a class III antiarrhythmic agent that prolongs the refractory period of the atrial and ventricular myocardium without any negative inotropic action. From July 2003 to September 2004, we treated 11 patients with NIF for perioperative arrhythmias (VT 5, VF 2, and AFL 4). NIF was administered by continuous intravenous infusion (0.3 to 0.4 mg/ kg/h) to prevent the recurrence of VT/VF and AFL. NIF prevented the recurrence of VT in 3 of the 5 cases. No recurrence was observed in 2 cases with VF. Furthermore, NIF prevented the recurrence of AFL in all the 4 patients. None of the patients exhibited changes in heart rate, cardiac output, and QTc interval. Additionally, no occurrence of Torsades de pointes was observed in any of the cases. In conclusion, NIF is an effective and safe antiarrhythmic agent for the treatment of perioperative arrhythmias under continuous monitoring of the QTc interval.

Adult↗
PubMed2006

Prevalence and characteristics of depression in a Japanese leprosarium from the viewpoints of social stigmas and ageing. A preliminary report.

OBJECTIVE: To investigate the prevalence and characteristics of depressed patients living in a Japanese leprosarium who have been isolated by national law and are now becoming very elderly. METHODS: We surveyed the prevalence of depressed patients living in the National Tamazenshouen Sanatorium, a major leprosarium in Japan. We also investigated the characteristics of patients who had suffered a depressive episode during the last 5 years (2000-2004). The characteristics of residents who committed suicide were also studied. RESULTS: At the time of the investigation, 48 out of 385 (12.5%) patients were depressed or had experienced a depressive episode. Forty-one residents had committed suicide since the leprosarium was established in 1907. Somatic symptoms and depressive moods were the predominant symptoms and were not limited to symptoms unique to leprosy. The period of isolation was not statistically correlated with the GDS-SF or PGC morale scale scores. CONCLUSION: The findings of this study emphasize the importance of consultation psychiatric for elderly leprosy residents and could be used as a reference for treatment in countries with ageing leprosy residents.

Aged↗
PubMed2005

Characterisation of glucose transporter (GLUT) gene expression in broiler chickens.

1. Glucose transporter (GLUT) proteins, one of which is the major insulin-responsive transporter GLUT4, play a crucial role in cellular glucose uptake and glucose homeostasis in mammals. The aim of this study was to identify the extent of mRNA expression of GLUT1, GLUT2, GLUT3 and GLUT8 in chickens intrinsically lacking GLUT4. 2. GLUT1 mRNA was detected in most tissues of 3-week-old broiler chickens, with the highest expression measured in brain and adipose tissue. GLUT2 was expressed only in the liver and kidney. GLUT3 was highly expressed in the brain. GLUT8 was expressed ubiquitously, with expression in kidney and adipose tissue relatively higher than that of other tissues. 3. Expression levels of GLUT isoforms 1, 3 and 8 in skeletal muscle tissue were very low compared to the other tissues tested. 4. [3H]Cytochalasin B binding assays on tissue from 3-week-old chickens showed that the number of cytochalasin B binding sites in skeletal muscle plasma membranes was higher than in liver plasma membranes. These results suggest that GLUT proteins and/or GLUT-like proteins that bind cytochalasin B are expressed in chicken skeletal muscles. 5. It is proposed that GLUT expression and glucose transport in chicken tissues are regulated in a manner different from that in mammals.

Adipose Tissue↗
PubMed2005

Polymorphisms in PTCH1 affect the risk of ameloblastoma.

Ameloblastoma is the most common odontogenic tumor, but the genetic nature of the changes in the tumor cells has been unclear. Mutations of CTNNB1 or PTCH1 are observed in many human tumors. Both CTNNB1 and PTCH1 are important in tooth development and are expressed in ameloblastoma. The aim of this study was to investigate whether genetic alterations of CTNNB1 and PTCH1 are present in ameloblastoma. We investigated 14 cases of ameloblastoma. The polymorphisms found in the ameloblastoma patients were further examined in a subsequent case-control study. We found a CTNNB1 mutation in one case of plexiform-type ameloblastoma. CGG triplet repeat-number polymorphism (CGG7/CGG8) in the 5'-untranslated region of PTCH1 was observed. The proportion of CGG8 alleles was significantly higher in the ameloblastoma group. The results of this study indicate a possible relationship between the CGG8 allele in PTCH1 and the risk for ameloblastoma.

Adult↗
PubMed2004

A human dual-color enzyme-linked immunospot assay for simultaneous detection of interleukin 2- and interleukin 4-secreting cells.

The enzyme-linked immunospot (ELISPOT) assay is an efficient technique for the enumeration of single cells secreting antibodies and cytokines. For simultaneous differentiation of individual cells producing interleukin-2 (IL-2) and interleukin-4 (IL-4) at a single cell level in human peripheral blood mononuclear cells (PBMCs), a human dual-color ELISPOT assay has been optimized. In the present system, the red spots corresponding to IL-2-secreting cells (T helper type 1, Th1, cells) were developed with horseradish peroxidase and the amino ethyl carbazole (AEC)/H2O2. The blue spots corresponding to IL-4-secreting cells (T helper type 2, Th2, cells) were developed with an alkaline phosphatase and the Vector blue. The usefulness of the assay method was tested. With this system, we could detect the IL-2- and IL-4-secreting cells simultaneously in human PBMCs of a juvenile rheumatoid arthritis (JRA) patient. This procedure provides useful information on clinical immune disorders.

Adult↗
PubMed2004

The immunohistochemical distribution of vimentin in human temporomandibular joint samples.

The aim of this investigation was to evaluate the immunohistochemical distribution of vimentin in the temporomandibular joint (TMJ) and to compare it with the control specimens. Immunohistochemical distribution in the disc and synovial membrane in 30 human TMJ (internal derangement of TMJ, n = 20; and control, n = 10) was studied immunohistologically using paraffin-embedded tissue and specific anti-human vimentin monoclonal antibody. Vimentin expression was distributed in chondrocyte-like cells, synovial cells and endothelial cells. There was an obvious distinction of vimentin immunoreactivity between the control specimens and internal derangement cases, in the posterior and/or anterior loose connective tissues. In particular, intensive vimentin expression was detected in the hypertrophic synovial membrane of internal derangement cases. The findings of the present study suggest that vimentin might be an important marker of pathological hypertrophy of the synovial membrane and/or connective tissue with internal derangement of TMJ.

Adult↗
PubMed2004

Training in tooth preparation utilizing a support system.

Tooth preparation is an essential technique for dental treatment, but it is a skill not easily learned by a dental student. To facilitate this leaning process, a new tooth preparation support system with a parallel link mechanism was developed. This study reports the educational efficiency of this system for dental students. Dental students with no experience in clinical practice were selected and divided into two groups; one trained with this support system; and the other, with freehand preparation. They prepared axial walls in right maxillary second premolars and molars mounted in a phantom manikin with an air-turbine handpiece. Convergence angles of the axial walls and parallelisms between axes of prepared teeth were evaluated. Training with the support system led to significantly smaller convergence angles and parallelisms as compared with freehand preparation training. With the freehand preparation after training, the convergence angles and parallelisms became smaller in the group trained with the support system than those trained with freehand. The above findings suggest that training in tooth preparation utilizing the newly developed support system can be one of practical programs that are useful for dental students to achieve greater competency in tooth preparation.

Bicuspid↗
PubMed2004

Pelvic imaging: multicystic uterine cervical lesions. Can magnetic resonance imaging differentiate benignancy from malignancy?

PURPOSE: To evaluate whether magnetic resonance imaging (MRI) can be used to differentiate between malignant and benign multicystic uterine cervical lesions. MATERIAL AND METHODS: Twenty-two patients with cervical adenocarcinomas, including minimal deviation adenocarcinoma, and five patients with benign multicystic lesions were classified as a percentage of solid components on MRI. Cystic components were further classified by average cyst diameter and signal intensity of the cyst fluid on T1WI. RESULTS: All nine of the entirely solid lesions were malignant. In contrast, two of the entirely cystic lesions were benign. Ten of the ordinary adenocarcinomas had both solid and cystic components. However, three of the 16 solid and cystic lesions were benign. Lesions composed of cysts smaller than 5mm tended to be malignant; however, some lesions composed of larger cysts were also malignant. Three of 5 lesions with low-signal and 7 of 10 with intermediate-signal fluid were malignant. CONCLUSION: The malignancy potential was higher in the lesions with a higher percentage of solid components. However, determining whether multicystic lesions were benign or malignant based on the existence of solid components, the average cyst size, and the signal intensity of cyst fluid was impossible. Although a multicystic lesion with solid components in the deep cervical stroma had been reported as a MR finding of a minimal deviation adenocarcinoma, this does not appear to be pathognomonic.

Adenocarcinoma↗
PubMed2004

Use of a PCR-based approach for sequencing whole mitochondrial genomes of insects: two examples (cockroach and dragonfly) based on the method developed for decapod crustaceans.

Recent development of a PCR-based approach for sequencing vertebrate mitochondrial genomes has attracted much attention as being more rapid and economical than traditional methods using cloned mtDNA and primer walking. Such a method has not been available for insect mitochondrial genomes, despite widespread use of them for the molecular phylogenetic, biogeographical and population genetic markers. A recently developed PCR-based approach for sequencing whole mitochondrial genomes of decapod crustaceans, which included the design of many versatile PCR primers for the latter, was applied with the same primers sets to mitochondrial genomes of two insects, smoky-brown cockroach Periplaneta fuliginosa (Serville, 1839) and skimmer dragonfly Orthetrum triangulare melania (Selys, 1883). Almost the entire region of the two mitochondrial genomes was successfully sequenced. Features of the two mitochondrial genomes are described and the usefulness of this PCR-based approach for sequencing insect mitochondrial genomes demonstrated.

Animals↗
PubMed2003

Role of neuronal glutamate transporter in the cysteine uptake and intracellular glutathione levels in cultured cortical neurons.

Cysteine uptake is the rate-limiting process in glutathione synthesis. Previously we have shown that the inhibitors of excitatory amino acid transporters (EAATs) significantly enhance glutamate toxicity via depletion of intracellular glutathione. In this study we show evidence that the neuronal glutamate transporter EAAT3 is directly enrolled in cysteine uptake in cultured neurons. Neuronal cysteine uptake was dependent on the extracellular sodium, and was suppressed by EAAT inhibitors. Cysteine uptake was suppressed by extracellular glutamate and aspartate, substrates of EAATs, and not by substrates of cysteine transporters. Intracellular glutathione levels were reduced by EAAT inhibitors, and not by inhibitors of cysteine transporters. Knock down of EAAT3 expression using antisense oligonucleotide significantly reduced cysteine uptake, intracellular glutathione level, and neuronal viability against oxidative stress. These facts indicate that EAAT3 functions as a cysteine transporter, and this function seems to be unique and distinct from cysteine transporters that have been reported.

Amino Acid Transport System X-AG↗
PubMed2002

Simultaneous analysis of dehydroacetic acid, benzoic acid, sorbic acid and salicylic acid in cosmetic products by solid-phase extraction and high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method for simultaneous determination of dehydroacetic acid (DHA), benzoic acid (BA), sorbic acid (SOA) and salicylic acid (SA) was developed for application to cosmetic products. Isocratic reversed-phase HPLC was employed for quantitative analysis using tetra-n-butylammonium (TBA) hydroxide as an ion-pair reagent. Cosmetic samples were purified by solid-phase extraction using Bond-Elut SI cartridges. Four acidic preservatives were eluted with methanol from cartridges. The HPLC assay was carried out using TSK gel ODS-80TM column (5 microm, 150 x 4.6 mm I.D.). The mobile phase consisted of a mixture of water and methanol (65:35, v/v) containing 2.5 mM TBA hydroxide adjusted with phosphoric acid to pH 7.0. The calibration curves of these preservatives showed good linearity with UV detection (235 nm). The correlation coefficients were better than 0.999 in all cases. The lower limits of detection (defined as a signal-to-noise ratio of about 3) were approximately 2.5 ng for DHA, 4.0 ng for BA, 2.0 ng for SOA and 5.5 ng for SA. The procedure described here is simple, selective and is suitable for quality control of finished cosmetic products.

Benzoic Acid↗
PubMed2002

Transplantation for accidental acute high-dose total body neutron- and gamma-radiation exposure.

Accidental exposure to acute high-dose total body neutron radiation is rare. We report a 35-year-old man exposed to a total body dose of 5.4 Gy neutron- and 8.5-13 Gy gamma-radiation in a radiation criticality accident. He received a blood stem cell transplant from his HLA-identical sister. There was bone marrow recovery with complete donor chimerism. Random chromatid breaks were observed in donor cells suggesting a bystander effect of neutron exposure. The subject died 82 days after the accident (75 days post transplant) from multi-organ failure.

Adult↗