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T Uemura

Publications and source records attributed to T Uemura.

At least 19 recordsLinked to original sources
PubMed2005

A case of toe macrodactyly treated by application of a vascularised nail graft.

Macrodactyly is a relatively rare congenital abnormality of the fingers and toes and is difficult to treat. We report a new method for treating toe macrodactyly in which a nail with a vascularised pedicle is raised, the toe is shortened to an appropriate length, and the nail transferred to an aesthetically appropriate proximal site. Although this technique is of a higher level of difficulty than conventional procedures involving pedicled nail flaps, allows aesthetically more favourable nail reconstruction by single-stage operation.

Adult↗
PubMed2005

Renal dysplasia with unilateral renal agenesis in a dog.

This report describes a renal dysplastic lesion associated with renal agenesis in a 3-year-old dog with chronic renal failure. Haematological examination revealed non-regenerative anaemia, azotaemia, increased creatinine and hyperphosphataemia. At necropsy, the right kidney and right ureter could not be identified. The left kidney was slightly enlarged, with a reduced cortico-medullary ratio. Histologically, the medulla of the left kidney had persistent mesenchyme and primitive tubules (tall pseudostratified columnar epithelium), dilated collecting ducts lined by flattened epithelium, and adenomatoid proliferation of cuboidal epithelium; fetal or immature glomeruli could not be identified. To our knowledge, this is the first report of a renal dysplastic lesion with unilateral agenesis in animals.

Animals↗
PubMed2005

Sirolimus conversion after liver transplantation: improvement in measured glomerular filtration rate after 2 years.

METHODS: We reviewed our prospectively maintained database of 2005 liver transplantations. Therapy was either started de novo or converted from calcineurin inhibitors (CNIs) to sirolimus as the main immunosuppressive agent for nephrotoxicity or rejection. Glomerular filtration rate (GFR) was determined with iodine 125-labeled sodium isthalamate (Glofil-125), and serum creatinine concentration was obtained before and 3 months after transplantation, and yearly in both groups. Sirolimus levels were 10 to 15 ng/mL in patients at less than 3 months after transplantations and 5 to 10 ng/mL in the remaining patients. All patients received mycophenolate mofetil as maintenance therapy. RESULTS: Data for 29 patients in the de novo group and 35 in the conversion group were reviewed. Patients in the de novo group demonstrated an acute cellular rejection rate of 17.2%, 40% of which were steroid resistant. In this group, 48.2% discontinuation of sirolimus was necessary because of adverse effects. Patients in the conversion group demonstrated an acute cellular rejection rate of 2.8% and a 34.3% rate of sirolimus discontinuation. Seventeen (56.7%) patients at 1 year and 8 (44.4%) patients at 2 years demonstrated continued improvement in GFR. In the conversion group, case-control analysis did not demonstrate a significant difference in GFR and serum creatinine concentration (P > .05) at 1 and 2 years after conversion. At the time of review, no patients in the conversion group required hemodialysis. CONCLUSIONS: Conversion to sirolimus therapy is an effective strategy in improving renal function in patients with CNI-induced nephrotoxicity and can be done without increased rejection. Most of our patients (65.7%) tolerated sirolimus conversion. Of these, 56.7% and 44.4% demonstrated continued increase in GFR with the CNI-free regimen at 1 and 2 years, respectively. Long-term, large-population, prospective, randomized, controlled studies should further validate these results.

Creatinine↗
PubMed2004

A six year follow up study of the subclinical effects of carbon disulphide exposure on the cardiovascular system.

AIMS: A six year prospective cohort study was conducted to clarify whether the current carbon disulphide (CS2) exposure level is low enough to prevent subclinical health impairment and/or to ameliorate health effects due to previous high exposure. This paper describes the effects on the cardiovascular systems. METHODS: The study subjects were 432 male workers exposed to CS2 and 402 non-exposed workers in Japan, all of whom were examined in 1992-93. A total of 251 CS2 exposed, 140 formerly exposed, and 359 non-exposed workers participated in the follow up survey (follow up rate 89.9%) in 1998-99. Mean duration of exposure was 19.3 years at the end the study. Mean CS2 and 2-thiothiazolidine-4-carboxylic acid (TTCA) concentrations were 5.0 ppm and 1.6 mg/g creatinine. Health items examined were serum biochemical indices including lipids and coagulation-fibrinolysis factors, blood pressure, aortic stiffness, ophthalmography, and electrocardiography at rest and after Master's double 2 step test. Potential confounding factors were adjusted for. RESULTS: Incidence of ischaemic findings, defined as Minnesota codes I, IV(1-3), V(1-3) (at rest and after the load), or receiving treatment for ischaemia, was significantly higher in the exposed workers, especially for the spinning/refining workers (adjusted OR 2.1; 95% CI 1.1 to 4.0) or the highest quartile of six year mean TTCA (adjusted OR 3.9; 95% CI 1.8 to 8.7), although the observed increase in risk was diminished when rigorous ECG criteria were applied. Incidence of retinal microaneurysm was increased with marginal significance. Among cardiovascular risk factors we examined, only blood pressure values were significantly increased in the exposed workers. CONCLUSIONS: Increased risk of ischaemic electrocardiogram findings among Japanese viscose rayon workers was observed. Although its clinical significance is to be discussed, the current Japanese occupational exposure limit for CS2, 10 ppm, would be high to prevent subclinical cardiovascular effects in this study population.

Adult↗
PubMed2004

Six year observational cohort study of the effect of carbon disulphide on brain MRI in rayon manufacturing workers.

AIMS: To clarify whether the current occupational exposure limit (OEL) for carbon disulphide (CS2) is low enough to prevent the occurrence of adverse effects on the cerebrovascular system. METHODS: A total of 432 male workers exposed to CS2 and 402 male referent workers in 11 Japanese viscose rayon factories were studied at baseline; 750 of these were followed up. Brain MRI was performed at both baseline and follow up surveys. Changes in the number of hyperintense spots in T2 weighted images (HIS), which point to so-called "silent cerebral infarctions", were evaluated over six years. A total of 666 subjects (217 exposed, 125 ex-exposed, and 324 referent subjects) who twice received brain MRI were subjected to analysis. Mean duration of exposure to the end of the study was 19.6 years for the exposed workers. The geometric mean CS2 (ppm) and TTCA (mg/g creatinine) concentrations for the past six years were 4.9 and 1.6 for all exposed workers, 5.8 and 1.9 for spinning/refining workers, and 2.7 and 0.9 for other exposed workers, respectively. RESULTS: Exposed subjects showed a significantly higher risk for an increase in the number of HIS over six years. Odds ratios adjusted for possible confounders in the exposed and ex-exposed workers were 2.27 (95% CI 1.37 to 3.76) and 1.33 (95% CI 0.70 to 2.54), respectively. No exposure-response relations were observed in a number of analyses among the exposed workers. CONCLUSIONS: Exposure to CS2 under the current Japanese OEL, 10 ppm, might increase the number of HIS in brain MRI. However, results should be interpreted with caution.

Adult↗
PubMed2003

Comparative analyses of serum vitellogenin levels in male and female Reeves' pond turtles (Chinemys reevesii) by an immunological assay.

A quantitative immunological method was developed for measuring serum vitellogenin levels of Reeves' pond turtles (Chinemys reevesii) to investigate the effects of endocrine disruptors on the freshwater ecosystem. Vitellogenin was induced by injecting estradiol-17beta into C. reevesii turtles (adult females, juvenile females, and males) and was purified from the turtle serum by EDTA-MgCl2 precipitation followed by gel filtration. Using a polyclonal antibody raised against C. reevesii vitellogenin, an enzyme-linked immunosorbant assay was established. The detectable range, recovery of vitellogenin, and coefficient of variation in this assay were 0.0040-1.0 microg.ml(-1), 85.3-109% and 3.4-11.5%, respectively. This assay was also applicable for measurement of the concentrations of vitellogenins from other species, Japanese pond turtles (Mauremys japonica) and red-eared turtles (Trachemys scripta). The serum vitellogenin concentration of 131 C. reevesii turtles captured at a Japanese local river was measured by the assay. In females, vitellogenin ranged from 0.10 microg.ml(-1) to 15,000 microg.ml(-1) with two peaks, 0.10-1.0 microg.ml(-1) (juveniles) and 1,000-10,000 microg.ml(-1) (adults). However, in males, it ranged from 0.10 microg.ml(-1) to 0.60 microg.ml(-1), showing one peak, 0.10-0.20 microg.ml(-1). Therefore, if relatively high concentrations of vitellogenin are detected in males or juvenile females, it is suggested that they would have been exposed to xenobiotic estrogens.

Animals↗
PubMed2003

Effectiveness of electrolyzed acidic water in killing Escherichia coli O157:H7, Salmonella enteritidis, and Listeria monocytogenes on the surfaces of tomatoes.

A study was conducted to evaluate the efficacy of electrolyzed acidic water, 200-ppm chlorine water, and sterile distilled water in killing Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes on the surfaces of spot-inoculated tomatoes. Inoculated tomatoes were sprayed with electrolyzed acidic water, 200-ppm chlorine water, and sterile distilled water (control) and rubbed by hand for 40 s. Populations of E. coli O157:H7, Salmonella, and L. monocytogenes in the rinse water and in the peptone wash solution were determined. Treatment with 200-ppm chlorine water and electrolyzed acidic water resulted in 4.87- and 7.85-log10 reductions, respectively, in Escherichia coli O157:H7 counts and 4.69- and 7.46-log10 reductions, respectively, in Salmonella counts. Treatment with 200-ppm chlorine water and electrolyzed acidic water reduced the number of L. monocytogenes by 4.76 and 7.54 log10 CFU per tomato, respectively. This study's findings suggest that electrolyzed acidic water could be useful in controlling pathogenic microorganisms on fresh produce.

Chlorine↗
PubMed2001

The seven amino acids of human RAMP2 (86) and RAMP3 (59) are critical for agonist binding to human adrenomedullin receptors.

When co-expressed with a receptor activity-modifying protein (RAMP) accessory protein, calcitonin receptor-like receptor (CRLR) can function as a calcitonin gene-related peptide receptor (CRLR-RAMP1) or an adrenomedullin (AM) receptor (CRLR-RAMP2/3). Here we report on the structural domain(s) involved in selective AM binding that were examined using various RAMP chimeras and deletion mutants. Co-expression of chimeric RAMPs and CRLR in HEK293 cells revealed that residues 77-101, situated in the extracellular N-terminal domain of human RAMP2 (hRAMP2), were crucial for selective AM-evoked cAMP production. More detailed analysis showed that deletion of hRAMP2 residues 86-92 significantly attenuated high-affinity (125)I-AM binding and AM-evoked cAMP production despite full cell surface expression of the receptor heterodimer and that deletion of hRAMP3 residues 59-65 had a similar effect. There is little sequence identity between hRAMP3 residues 59-65 and hRAMP2 residues 86-92; moreover, substituting alanine for Trp(86) (Ala(87)), Met(88), Ile(89), Ser(90), Arg(91), or Pro(92) of hRAMP2 had no effect on AM-evoked cAMP production. It thus seems unlikely that any one amino acid residue is responsible for determining selective AM binding or that AM binds directly to these peptide segments. Instead these findings suggest that the respective seven-amino acid sequences confer selectivity either by directly contributing to the structure of ligand binding pocket or by allosteric modulation of the conformation of CRLR.

Adrenomedullin↗
PubMed2001

Asymmetric colocalization of Flamingo, a seven-pass transmembrane cadherin, and Dishevelled in planar cell polarization.

The Drosophila wing provides an appropriate model system for studying genetic programming of planar cell polarity (PCP) [1-4]. Each wing cell respects the proximodistal (PD) axis; i.e., it localizes an assembly of actin bundles to its distalmost vertex and produces a single prehair. This PD polarization requires the redistribution of Flamingo (Fmi), a seven-pass transmembrane cadherin, to proximal/distal cell boundaries; otherwise, the cell mislocalizes the prehair [5]. Achievement of the biased Fmi pattern depends on two upstream components in the PCP signaling pathway: Frizzled (Fz), a receptor for a hypothetical polarity signal, and an intracellular protein, Dishevelled (Dsh) [6-8]. Here, we visualized endogenous Dsh in the developing wing. A portion of Dsh colocalized with Fmi, and the distributions of both proteins were interdependent. Furthermore, Fz controlled the association of Dsh with cell boundaries, which association was correlated with the presence of hyperphosphorylated forms of Dsh. Our results, together with a recent study on Fz distribution [9], support the possibility that Fz, Dsh, and Fmi constitute a signaling complex and that its restricted localization directs cytoskeletal reorganization only at the distal cell edge.

Adaptor Proteins, Signal Transducing↗
PubMed2001

rDrak1, a novel kinase related to apoptosis, is strongly expressed in active osteoclasts and induces apoptosis.

This is the first report of a novel serine/threonine kinase, rabbit death-associated protein (DAP) kinase-related apoptosis-inducing protein kinase 1 (rDRAK1), involved in osteoclast apoptosis. We searched for osteoclast-specific genes from a cDNA library of highly enriched rabbit osteoclasts cultured on ivory. One of the cloned genes has a high homology with human DRAK1 (hDRAK1), which belongs to the DAP kinase subfamily of serine/threonine kinases. By screening a rabbit osteoclast cDNA library and 5'-RACE (rapid amplification of cDNA ends), we obtained a full length of this cDNA, termed rDRAK1. The sequencing data indicated that rDRAK1 has 88.0, 44.6, 38.7, and 42.3% identity with hDRAK1, DAP kinase, DRP-1, and ZIP (zipper-interacting protein) kinase, respectively. To clarify the role of DRAK1 in osteoclasts, we examined the effect of three osteoclast survival factors (interleukin-1, macrophage colony-stimulating factor, and osteoclast differentiation-inducing factor) on rDRAK1 mRNA expression and the effect of rDRAK1 overexpression on osteoclast apoptosis. The results suggested that these three survival factors were proved to inhibit rDRAK1 expression in rabbit osteoclasts. After transfection of a rDRAK1 expression vector into cultured osteoclasts, overexpressed rDRAK1 was localized exclusively to the nuclei and induced apoptosis. Hence, rDRAK1 may play an important role in the core apoptosis program in osteoclast.

Amino Acid Sequence↗
PubMed2001

In vivo evaluation of a novel porous hydroxyapatite to sustain osteogenesis of transplanted bone marrow-derived osteoblastic cells.

Biosynthetic bone grafts are considered to contain one or more of three critical components: osteoprogenitor cells, an osteoconductive matrix, and osteoinductive growth factors. The basic requirements of the scaffold material are biocompatibility, mechanical integrity, and osteoconductivity. A major design problem is satisfying these requirements with a single composite. In this study, we hypothesize that one composite that combines bone marrow-derived osteoblasts and a novel mechanical reinforced porous hydroxyapatite with good biocompatibility and osteoconductivity (HA/BMO) can reach these requirements. A novel sintered porous hydroxyapatite (HA) was prepared by the following procedures. The HA slurry was foamed by adding polyoxyethylenelaurylether (PEI) and mixing. The pores were fixed by crosslinking PEI with diepoxy compounds and the HA porous body was sintered at 1200 degrees C for 3 h. The HA sintered porous body had a high porosity (77%), and was completely interconnected. Average pore diameter was 500 microm and the interconnecting path 200 microm in diameter. The compressive (17 MPa) and three-point bending (7 MPa) strengths were high. For in vivo testing, the 2-week subcultured HA/BMO (+) composites were implanted into subcutaneous sites of syngeneic rats until 8 weeks after implantation. These implants were harvested at different time points and prepared for the biochemical analysis of alkaline phosphatase activity (ALP) and bone osteocalcin content (OCN), and histological analysis. ALP and OCN in the HA/BMO group were much higher than those in the HA without BMOs control group 1 week after implantation (p < 0.001). Light microscopy revealed mature bone formation in the HA/BMO composite 4 weeks after implantation. In the SEM study, mineralized collagenous extracellular matrix was noted in HA/BMO composite 2 weeks after implantation with numbers of active osteoblasts. We conclude that the composite of the novel HA and cultured BMOs has osteogenic ability in vivo. These results provide a basis for further studies on the use of this composite as an implant in orthopaedic surgery.

Alkaline Phosphatase↗
PubMed2001

A longitudinal study of disturbances of the hypothalamic-pituitary-adrenal axis in women with progestin-negative functional hypothalamic amenorrhea.

OBJECTIVE: To longitudinally evaluate disturbances of the hypothalamic-pituitary-adrenal (HPA) axis in women with secondary progestin-negative hypothalamic amenorrhea. DESIGN: Retrospective cohort study. SETTING: Yokohama City University, Yokohama, Japan. PATIENT(S): Twenty-four women with progestin-negative hypothalamic amenorrhea. INTERVENTION(S): Administration of human corticotropin-releasing hormone (hCRH) and treatment with a combination of estrogen and progesterone. MAIN OUTCOME MEASURE(S): Plasma cortisol and ACTH concentrations and period required for recovery from amenorrhea. RESULT(S): Plasma ACTH concentrations 30 and 60 minutes after injection of hCRH and the percent maximum increment (%Cmax) of ACTH were significantly lower in the amenorrheic patients compared with the control group patients. The basal cortisol was significantly higher, and the %Cmax of cortisol was significantly lower. In the 16 patients who recovered from amenorrhea, there was a significant positive correlation (Y = 1.93X-10.8, r = 0.629) between the basal cortisol concentrations (X) and the period for recovery (Y). The serum E2 gradually increased before recovery, and this E2 increase was preceded by changes in the plasma cortisol concentration and the %Cmax values of cortisol and ACTH. CONCLUSION(S): The CRH test might be useful for evaluating the roles of stress and for estimating the period required for recovery in hypothalamic amenorrhea.

Adrenocorticotropic Hormone↗
PubMed2001

Inhibition of DNA synthesis in cultured hepatocytes by endotoxin-conditioned medium of activated stellate cells is transforming growth factor-beta and nitric oxide-independent.

Activated hepatic stellate cells play a major role in the pathophysiology of chronic liver disease. They can influence the metabolism of hepatocytes by producing a variety of cytokines and growth factors. Upon stimulation with endotoxin, stellate cells also synthesize nitric oxide (NO), a potent mediator of growth of several cell types including hepatocytes. We investigated the effect of serum-free medium conditioned by activated stellate cells in the absence and presence of endotoxin on NO and DNA synthesis in hepatocytes. Stellate cells and hepatocytes were isolated by enzymatic digestion of the liver. Stellate cells were cultured for 10 days after which the majority exhibited alpha-smooth muscle actin (a marker for activated cells); hepatocytes were used after overnight culture. While the medium conditioned by stellate cells in the absence of endotoxin stimulated DNA synthesis in hepatocytes, medium conditioned in its presence inhibited this process in an endotoxin concentration-dependent manner (10 - 1000 ng ml(-1)). Endotoxin-conditioned stellate cell medium also stimulated NO synthesis in hepatocytes; the effect was consistent with increased protein and mRNA expression of inducible NO synthase (iNOS). However, inhibition of DNA synthesis in hepatocytes caused by endotoxin-conditioned stellate cell medium was unaffected by the NOS inhibitor, L-N(G)-monomethylarginine (L-NMMA), guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), and neutralizing antibodies for TGF-beta, IL-1beta, IL-6 and TNF-alpha. These results indicate that factors other than these cytokines produced by activated stellate cells upon stimulation with endotoxin or by hepatocytes challenged with endotoxin-conditioned stellate cell medium inhibit DNA synthesis in hepatocytes.

Animals↗
PubMed2001

Developmental roles and molecular characterization of a Drosophila homologue of Arabidopsis Argonaute1, the founder of a novel gene superfamily.

BACKGROUND: Arabidopsis Argonaute1 (AGO1) is the founder of a novel gene superfamily that is conserved from fission yeasts to humans. AGO1, and several other members of this superfamily are necessary for stem cell renewal or RNA interference. However, little has been reported about their roles in animal development or about the molecular activities of any of the members. RESULTS: We have isolated a Drosophila homologue of AGO1, dAGO1, in our attempt to search genetically for regulators of Wingless (Wg) signal transduction. dAGO1 is broadly expressed in the embryo and the imaginal disc. dAGO1 over-expression at wing margins suggested that it behaves as a positive regulator in the genetic background employed. Loss-of-function mutations of dAGO1, unexpectedly, did not give typical segment polarity phenotypes of the wg class; instead, dAGO1 maternal and zygotic mutant embryos showed developmental defects, with malformation of the nervous system being the most prominent. The mutant decreased in the numbers of several types of neurones and glia examined. The dAGO1 protein was distributed in the cytoplasm and co-sedimented with poly(U)- or poly(A)-conjugated beads. CONCLUSION: Our results suggest that the dAGO1 protein exerts its developmental functions by binding to RNA either directly or indirectly.

Amino Acid Sequence↗