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T Akiyama

Publications and source records attributed to T Akiyama.

At least 19 recordsLinked to original sources
PubMed2006

Wnt signalling and the actin cytoskeleton.

The tumour suppressor adenomatous polyposis coli (APC) is mutated in sporadic and familial colorectal tumours. APC binds to beta-catenin, a key component of the Wnt signalling pathway, and induces its degradation. In addition to this role, there is increasing evidence for additional roles of APC, including the organization of cytoskeletal networks. APC interacts with microtubules and accumulates at their plus ends in membrane protrusions. Also, it has been reported that APC is associated with the plasma membrane in an actin-dependent manner. Moreover, APC interacts with IQGAP1, an effector of Rac1 and Cdc42, and APC-stimulated guanine nucleotide exchange factor (Asef), a Rac1-specific guanine nucleotide exchange factor (GEF). IQGAP1 mediates association of APC with cortical actin in the leading edge of migrating cell and both proteins are required for cell polarization and directional migration. APC interacts with Asef and stimulates its activity, thereby regulating the actin cytoskeletal network, cell morphology, adhesion and migration. Truncated mutant APCs present in colorectal tumour cells activate Asef constitutively and contribute to their aberrant migratory properties, which may be important for adenoma formation as well as tumour progression to invasive malignancy.

Actins↗
PubMed2006

A case of hyperparathyroidism-jaw tumour syndrome found in the treatment of an ossifying fibroma in the maxillary bone.

Hyperparathyroidism-jaw tumour (HPT-JT) syndrome is characterized by parathyroid tumours as well as by ossifying fibromas of the mandible and maxilla, renal cysts, or Wilms' tumours. Recently, the gene responsible for HPT-JT syndrome has been identified as the HRPT2 tumour suppressor gene. In an 18-year-old male, a tumour in the maxilla was first diagnosed as an ossifying fibroma. During biochemical screening before surgery, the patient received a diagnosis of primary hyperparathyroidism. Neck computed tomography scanning showed a parathyroid tumour. Surgical excisions to remove the jaw tumour and parathyroid adenoma were performed. The postoperative course has been uneventful and a follow up at 2 years revealed no evidence of recurrence. The HRPT2 germline mutation of 39delC was detected in the proband, but not in his unaffected parents. These results suggested that the germline mutation occurred de novo.

Adenoma↗
PubMed2006

Can monitoring of serum 8-OHdG level for 2 hours after renal transplantation predict prognosis of the graft?

8-Hydroxy-2'-deoxyguanosine (8-OHdG) is an oxidant of deoxyguanosine, a base in the construction of DNA. We examined the extent of DNA damage to the graft through oxidative stress after renal transplantation. Seven renal transplant patients were enrolled in this study. Before reperfusion of the grafts, the level of serum 8-OHdG was measured using enzyme-linked immunosorbent assay. No relationship was found between the level of serum 8-OHdG just before reperfusion and the postoperative course. In all cases, the level of serum 8-OHdG increased after reperfusion and decreased within 2 hours. In six cases, it remained almost the same as the preoperative level. A faster rate of decrease from the first peak of serum 8-OHdG was associated with a lower nadir serum creatinine and reduced occurrence of acute rejection. This study suggested that immediate calming of the oxidative stress following reperfusion may potentially have a positive influence on graft prognosis. In addition, biomarkers of oxidative stress may predict graft prognosis.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2006

Creatol, an oxidative product of creatinine in kidney transplant patients, as a useful determinant of renal function: a preliminary study.

Creatol (CTL, 5-hydroxycreatinine) is a creatinine (Cr) oxidative metabolite, which was originally isolated from the urine of patients with chronic renal failure, representing a candidate for a uremic toxin. The effectiveness of CTL as an indicator of oxidative stress after kidney transplantation has not been reported. Therefore, we examined the relation between the change in oxidative stress (using CTL) in renal transplant patients and their change in renal function (using Cr). The serum Cr and serum and urine CTL were examined in five renal transplant patients. Serum CTL closely correlated with serum Cr. Serum CTL also correlated with urine CTL, but in some cases there was a time lag. Both the ratio of CTL/(Cr) and serum CTL observed in patient 2 were slow to improve after transplantation. The process through which oxidative stress was reduced was shown by the index of renal damage correlated with kidney function oxidative stress (using serum CTL) after transplantation. Our data suggested that CTL/Cr may be a good indicator of graft prognosis.

ABO Blood-Group System↗
PubMed2005

Temperament and job stress in Japanese company employees.

BACKGROUND: This study aims to demonstrate the relevance of temperament to job stress. METHOD: The subjects were 848 male and 366 female Japanese company employees. Temperament Evaluation of Memphis, Pisa, Paris and San Diego-Autoquestionnaire version (TEMPS-A) and Munich Personality Test (MPT) were administered to assess temperaments, and the NIOSH Generic Job Stress Questionnaire (GJSQ) to assess job stress. We used hierarchical multiple linear regression analysis in order to demonstrate whether temperament variables added any unique variance after controlling the effects of other predictors such as gender, age and job rank. RESULTS: In all subscales of the GJSQ, temperament predicted a large share of the variance in job stress. Remarkably, for interpersonal relationship stressors, the temperament variables added greater variance than that predicted by gender, age and job rank. Summary of the hierarchical linear regression analysis showed that the irritable temperament was associated with the most prominent vulnerability, followed by cyclothymic and anxious temperaments. The schizoid temperament had difficulty in the area of social support. On the other hand, the hyperthymic temperament displayed significant robustness in facing most job stressors; the melancholic type showed a similar pattern to a lesser degree. LIMITATION: The findings may be different in a clinical Japanese sample, or a cohort of healthy employees from a different cultural background. CONCLUSIONS: Temperament influences job stress significantly-indeed, it impacts on such stress with greater magnitude than age, gender and job rank in most areas examined. Temperament influences interpersonal relationship stressors more than workload-related stressors. Interestingly, in line with previous clinical and theoretical formulations, the hyperthymic and melancholic types actually appear to be "hyper-adapted" to the workplace.

Adult↗
PubMed2005

Involvement of transforming growth factor-beta and thrombopoietin in the pathogenesis of myelodysplastic syndrome with myelofibrosis.

We investigated the cause of myelofibrosis and proliferation of megakaryocytes in myelodysplastic syndrome with myelofibrosis (MDS-MF (+)). Plasma-transforming growth factor-beta1 (PTGF-beta1) concentrations closely correlated with myelofibrosis grade in MDS-MF (+) and were higher than those in idiopathic myelofibrosis (IMF), essential thrombocythemia (ET), idiopathic thrombocytopenic purpura (ITP), MDS-without MF (MDS-MF (-)) or healthy volunteers (HV). Peripheral blood mononuclear cells from MDS-MF (+) patients expressed more TGF-beta1 mRNA than those from IMF, MDS-MF (-) or HV. When we immunostained bone marrow specimens of MDS-MF (+) for TGF-beta, the intensity of blasts was apparently higher than that of megakaryocytes, while in MDS-MF (-), megakaryocytes were immunostained with a similar intensity as that in MDS-MF (+), but blasts were negative for staining. In IMF, megakaryocytes, monocytes and small mononuclear cells representing CD34+ cells were all similarly stained with a much lower intensity than that of blasts in MDS-MF (+). The number of bone marrow megakaryocytes were increased the most in MDS-MF (+), followed by ET, ITP, MDS-MF (-) and NHL and correlated with plasma thrombopoietin (TPO) levels or with plasma TGF-beta1 levels, respectively, in each disease. Thus, in MDS-MF (+), both myelofibrosis and the increased megakaryocytes were ascribed to overproduction of TGF-beta1 from blasts.

Adult↗
PubMed2005

Myocardial interstitial choline and glutamate levels during acute myocardial ischaemia and local ouabain administration.

AIM: Noradrenaline (NA) uptake transporters are known to reverse their action during acute myocardial ischaemia and to contribute to ischaemia-induced myocardial interstitial NA release. By contrast, functional roles of choline and glutamate transporters during acute myocardial ischaemia remain to be investigated. Because both transporters are driven by the normal Na+ gradient across the plasma membrane in a similar manner to NA transporters, the loss of Na+ gradient would affect the transporter function, which would in turn alter myocardial interstitial choline and glutamate levels. The aim of the present study was to examine the effects of acute myocardial ischaemia and the inhibition of Na+,K+-ATPase on myocardial interstitial glutamate and choline levels. METHODS: In anaesthetized cats, we measured myocardial interstitial glutamate and choline levels while inducing acute myocardial ischaemia or inhibiting Na+,K+-ATPase by local administration of ouabain. RESULTS: The choline level was not changed significantly by ischaemia (from 0.93 +/- 0.06 to 0.82 +/- 0.13 microm, mean +/- SE, n = 6) and was decreased slightly by ouabain (from 1.30 +/- 0.06 to 1.05 +/- 0.07 microm, P < 0.05, n = 6). The glutamate level was significantly increased from 9.5 +/- 1.9 to 34.7 +/- 6.1 microm by ischaemia (P < 0.01, n = 6) and from 8.9 +/- 1.0 to 15.9 +/- 2.3 microm by ouabain (P < 0.05, n = 6). Inhibition of glutamate transport by trans-L-pyrrolidine-2,4-dicarboxylate (t-PDC) suppressed ischaemia- and ouabain-induced glutamate release. CONCLUSION: Myocardial interstitial choline level was not increased by acute myocardial ischaemia or by Na+,K+-ATPase inhibition. By contrast, myocardial interstitial glutamate level was increased by both interventions. The glutamate transporter contributed to glutamate release via retrograde transport.

Acetylcholine↗
PubMed2005

Geographical characterization of the triatomine infestations in north-central Guatemala.

In an entomological study in 2002, the degree of domestic and peridomestic infestation with triatomine bugs and the geographical distribution of such infestations were investigated in north-central Guatemala. The survey team searched for triatomines in houses constructed with mud walls or thatched roofs, in villages suspected of being infested. The level of infestation observed was lower than that seen in the same area and in eastern Guatemala, in a preliminary survey, 3 years earlier. Most of the infestations detected were of Triatoma dimidiata but even this species was found in <7% of the houses investigated. Infestations with Rhodnius prolixus or other potential vectors of Trypanosoma cruzi were much rarer. The generally low levels of infestation make the elimination of R. prolixus and the reduction of the domestic population of Tri. dimidiata feasible in the study area. The southern part of the study area had higher levels of domestic infestation and colonization than the north, and peridomestic infestation was highest in the south-west. Given such geographical variation in the pattern of infestation, it would seem wise to stratify the study region into areas of high, moderate and low-risk of human-triatomine contact, so that appropriate vector-control strategies can be targeted at the worst-affected areas. Regular entomological surveillance, ideally with community participation, is recommended. Analysis of the relationship between the geographical patterns of infestation and factors such as vegetation, altitude and vector migration would be useful.

Animals↗
PubMed2005

The first grid for the oral and maxillofacial region and its application for speech analysis.

OBJECTIVES: Introduction of a new grid-based method for analyzing speech functions which takes into account the related information of patients' data and the oral air flow with pronouncing analyzed by computational fluid dynamics. METHODS: An on-line speech analyzer was developed for clinical use utilizing GridPort2.3.1 based on globus2.4.2, comprising several computational tools such as unified data storage, semantic data analysis, computational fluid dynamics analysis and three-dimensional visualization of calculated results from different hardware sources with various types of operation systems. RESULTS: The power transportation layer between dental clinics and computational and storage resources could be provided by using a WWW-based portal. The backend data management system could be constructed using a storage resource broker (SRB) and extensible mark up language (XML). CONCLUSIONS: The new method allows the construction of a data warehouse through this grid-based speech function analysis in order to extract the principal factors related to speech disorders.

Database Management Systems↗
PubMed2004

Identification of zonal flows in a toroidal plasma.

This Letter presents experimental confirmation of the presence of zonal flows in magnetically confined toroidal plasma using an advanced diagnostic system--dual heavy ion beam probes. The simultaneous observation of an electric field at two distant toroidal locations (approximately 1.5 m apart) in the high temperature (approximately 1 keV) plasma provides a fluctuation spectrum of electric field (or flow), a spatiotemporal structure of the zonal flows (characteristic radial length of approximately 1.5 cm and lifetime of approximately 1.5 ms), their long-range correlation with toroidal symmetry (n=0), and the difference in the zonal flow amplitude with and without a transport barrier. These constitute essential elements of turbulence-zonal flow systems, and illustrate one of the fundamental processes of structure formation in nature.

Journal Article↗
PubMed2004

Differential expression of an S-adenosyl-L-methionine decarboxylase gene involved in polyamine biosynthesis under low temperature stress in japonica and indica rice genotypes.

We have investigated the regulation of the rice (Oryza sativa) gene OsSAMDC, which encodes an S-adenosyl-L-methionine decarboxylase (SAMDC) involved in polyamine biosynthesis. Clones representing genes differentially expressed at 5 degrees C and 20 degrees C were isolated from a cDNA library prepared from the chilling-tolerant japonica-type cultivar Yukihikari. The full-length OsSAMDC cDNA consists of 1560 bp, with the longest ORF encoding a polypeptide of 398 amino acids. Southern analysis indicated that there are two types of gene for SAMDC in the Yukihikari genome. Analysis of the expression of OsSAMDC by Northern hybridization revealed relatively high levels of mRNA in the leaves, nodes and internodes. We also analyzed the response of OsSAMDC to various abiotic stress treatments and plant hormones. Upon exposure to cold stress (5 degrees C) the level of OsSAMDC transcripts in the cold-resistant Yukihikari genotype continued to increase for up to 72 h. In contrast, there was no change in OsSAMDC transcription in the susceptible indica cultivar TKM9 under the same conditions. Ethephon induced the accumulation of OsSAMDC transcripts to similar extents in both genotypes. Examination of polyamine levels in the cold-resistant Yukihikari genotype revealed that spermidine levels were elevated during the course of cold treatment. These results suggest that the induction of the OsSAMDC gene in response to cold may be used as a molecular marker for the ability of rice seedlings to withstand exposure to low temperatures.

Adenosylmethionine Decarboxylase↗
PubMed2004

Autoantibodies to REG, a beta-cell regeneration factor, in diabetic patients.

BACKGROUND: Regenerating gene (Reg) product, Reg, acts as an autocrine/paracrine growth factor for beta-cell regeneration. The presence of autoimmunity against REG may affect the operative of the regenerative mechanisms in beta cells of Type 1 and Type 2 diabetes patients. We screened sera from Type 1 and Type 2 diabetes subjects for anti-REG autoantibodies, searched for correlations in the general characteristics of the subjects with the presence of anti-REG autoimmunity, and tested the attenuation of REG-induced beta-cell proliferation by the autoanitibodies. MATERIAL AND METHODS: We examined the occurrence of anti-REG autoantibodies in patients' sera (265 Type 1, 368 Type 2 diabetes patients, and 75 unrelated control subjects) by Western blot analysis, and evaluated inhibitory effects of the sera on REG-stimulated beta-cell proliferation by a 5'-Bromo-2'-deoxyuridine (BrdU) incorporation assay in vitro. RESULTS: Anti-REG autoantibodies were found in 24.9% of Type 1, 14.9% of Type 2 and 2.7% of control subjects (P = 0.0004). There were significant differences between the autoantibody positive and negative groups in the duration of disease in the Type 1 subjects (P = 0.0035), and the age of onset in the Type 2 subjects (P = 0.0274). The patient sera containing anti-REG autoantibodies significantly attenuated the BrdU incorporation by REG (35.6 +/- 4.06% of the control), whereas the nondiabetic sera without anti-REG autoantibodies scarcely reduced the incorporation (88.8 +/- 5.10%). CONCLUSION: Anti-REG autoantibodies, which retard beta-cell proliferation in vitro, are found in some diabetic patients. Thus, autoimmunity to REG may be associated with the development/acceleration of diabetes in at least some patients.

Adolescent↗
PubMed2004

Effect of an early intervention programme on low birthweight infants with cerebral injuries.

OBJECTIVE: To determine the effect of an early intervention programme (EIP) on low birthweight infants with cerebral injuries. METHODS: Subjects were 23 high-risk low birthweight infants (periventricular leukomalacia 15, intraventricular haemorrhage 5, both 3) receiving care in the neonatal intensive care unit (NICU) at Nagasaki University Hospital. Subjects were randomly assigned to the EIP group (n = 12) or the control group (n = 11). Participants in the EIP group received a Neonatal Behavioral Assessment scale (NBAS)-based intervention combined with developmental support designed to enhance the infants' development and the quality of the parent-infant relationship. The control group received routine medical nursing care without the EIP. The EIP began prior to discharge from the NICU and lasted until 6 months of corrected age. All children were examined on the NBAS preintervention and again at 44 weeks postconceptional age. Maternal anxiety status (STAI) and maternal feelings of confidence in dealing with her baby (LCC) were measured pre and postintervention. Mental and motor development was assessed postintervention using the Bayley Scale of Infant Development. RESULTS: Orientation and State Regulation of infant behavioural profiles, the STAI and LCC scores significantly improved in the EIP group (mean difference (95% CI): Orientation 0.7 (0.4, 1.1), State Regulation 0.9 (0.3, 1.5), STAI -5.5 (- 9.1, -1.9, LCC 5.3 (4.2, 6.5)), but not in the control group. Bayley mental developmental index (MDI) score in the EIP group was higher than in the control group, but there was no significant difference between the two groups (mean difference (95% CI): MDI 8.5 (- 0.8, 17.8), PDI 6.7 (- 1.9, 15.4)). CONCLUSION: The EIP has beneficial effects on neonatal neurobehavioural development and maternal mental health of low birthweight infants with cerebral injuries. This evidence suggests that short-term changes in maternal mental health and infant neurobehaviour promoted by an EIP may serve to initiate a positive interaction between parents and infants.

Apgar Score↗
PubMed2004

Randomised controlled trial of swaddling versus massage in the management of excessive crying in infants with cerebral injuries.

BACKGROUND: Infants with neonatal cerebral insults are susceptible to excessive crying as a result of difficulties with self-regulation. AIMS: To compare the effectiveness of swaddling versus massage therapy in the management of excessive crying of infants with cerebral insults. METHODS: Randomised three-week parallel comparison of the efficacy of two intervention methods. Infants with symptoms of troublesome crying and their parents were randomly assigned to a swaddling intervention group (n = 13) or a massage intervention group (n = 12). RESULTS: The amount of total daily crying decreased significantly in the swaddling group, but did not decrease significantly in the massage group. Infant behavioural profiles and maternal anxiety levels improved significantly in the swaddling group post-intervention. Parents in the swaddling group were more satisfied with the effectiveness of the intervention in reducing crying than parents in the massage group. CONCLUSION: Results indicate that swaddling may be more effective than massage intervention in reducing crying in infants with cerebral injuries.

Attitude to Health↗
PubMed2004

Outcomes of kidney transplants from non-heart-beating deceased donors as reported to the Japan Organ Transplant Network from April 1995-December 2003: a multi-center report.

Between April 1995-December 2003, 1,324 deceased donor kidney transplantations were performed in 139 transplant institutes in Japan. Of these, 45 transplants were from heart-beating and 1,279 transplants were from non-heart-beating deceased donors (NHBDD). Clinical outcomes for the 1,279 recipients of NHBDD kidney transplants were investigated. The overall 5-year patient and graft survival rates were 90% and 72%, respectively. A total of 112 NHBDD kidney grafts never functioned after transplantation and the recipients had to remain on dialysis. The causes of nonfunction were rejection, primary nonfunction, death, thrombosis and others in the order of the incidence. The major causes of graft loss were nonfunction, death, chronic rejection and acute rejection in that order. Major causes of recipient deaths were pneumonia, sepsis and CVA within 12 months, and heart diseases, sepsis, malignancy and pneumonia more than 12 months after transplantation. Kidneys from female donors, donors aged 15 or less or over age 60, donors with extrinsic causes of death other than head trauma, recipients over age 60 and those with diabetic nephropathy as their original disease were found to be at risk for poor graft survival. The lowest and last donor serum creatinine level did not influence the incidence of nonfunction or graft survival. However, graft survival was significantly poorer among recipients of older "expanded" donor kidneys than for recipients of younger grafts. The warm and total ischemia times should be kept shorter than 30 minutes (better 15 minutes), and 12 hours, respectively to minimize the incidence of nonfunction and early graft loss. It is especially important in cases with WIT over 30 minutes that the total ischemia should be kept within 12 hours. Cannulation before cardiac standstill was important to reduce the incidence of nonfunction and achieve high graft survival rates with NHBDD kidneys. The discontinuance of ventilator support also reduced the incidence of graft nonfunction. The combination of CsA or Tacrolimus and MMF as both the induction and maintenance regimen significantly improved graft survival. The use of either anti-T cell antibodies or basiliximab was also associated with significantly better graft survival for NHBDD kidneys. The combination of basiliximab, CsA and MMF resulted in a graft survival rate of 98% at one and 2 years.

Adolescent↗