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S Matsuura

Publications and source records attributed to S Matsuura.

At least 19 recordsLinked to original sources
PubMed2005

Incidence and risk factors of clinical characteristics, tacrolimus pharmacokinetics, and related genomic polymorphisms for posttransplant diabetes mellitus in the early stage of renal transplant recipients.

PURPOSE: Posttransplant diabetes mellitus (PTDM) is an important complication in a tacrolimus (TAC)-based immunosuppressive regimen. The present study investigated the incidence, clinical risk factors, TAC pharmacokinetics (PK), and genomic polymorphisms related to TAC-PK or diabetes mellitus (DM) under the TAC-based immunosuppressive protocol. PATIENTS AND METHODS: Seventy-one nondiabetic renal allograft recipients transplanted from February 1998 to March 2004 were studied. Patients with over 6.5 mg/dL of hemoglobin A1c on sequential blood samples or requiring insulin or oral antidiabetic agents around 6 months after transplantation were diagnosed as having PTDM. RESULTS: Six months after transplantation, 10 recipients (14.1%) developed PTDM. The positive risk factors were age (P = .003) and body mass index (P = .035). There were no significant differences in gender distribution, pretransplant dialysis period, dialysis modality, acute rejection rate, total steroid doses, TAC-PK, or its related genomic polymorphisms between the two groups. In the DM-related polymorphisms, the frequency of PTDM was significant higher in patients with the VDR TaqI tt or Tt genotype than in those with the TT genotype (P = .013). After a multivariate analysis, age over 50 years (P = .007, odds ratio 8.92) and the presence of VDR TaqI t allele (P = .043, odds ratio 6.71) were correlated with the development of PTDM. CONCLUSION: The incidence of PTDM in our series was 14.1%. Age over 50 years was a risk factor. The presence of VDR TaqI t allele might be a risk for PTDM. An association between TAC-PK and development of PTDM was not observed.

Body Mass Index↗
PubMed2005

The influence of mycophenolate mofetil versus azathioprine and mycophenolic acid pharmacokinetics on the incidence of acute rejection and infectious complications after renal transplantation.

PURPOSE: The present retrospective study investigated the influence of mycophenolate mofetil (MMF) instead of azathioprine (AZA) as part of tacrolimus-based immunosuppression. Mycophenolic acid (MPA) pharmacokinetic (PK) parameters were used for associations with the incidence of acute rejection (AR) episodes and infectious complications after renal transplantation. METHODS: The 66 consecutive renal transplant recipients reported herein excluded ABO-incompatible transplants or cytomegalovirus (CMV)-seronegative recipients. The immunosuppressive regimen consisted of tacrolimus, steroids, and AZA 1-2 mg/kg/d in 22 patients (between February 1998 and December 2000) or MMF 2 g/d in 44 patients (since January 2001). CMV infection was defined as positive CMV-antigenemia. MPA PK was studied on day 28 after transplantation in 21 recipients. RESULTS: AR occurred in 13.6% of patients in the MMF group compared with 18.2% in the AZA group. The viral infection (CMV, varicella zoster virus, adenovirus hemorrhagic cystitis, and malignancy related to Epstein-Barr [EB] virus) rate was 22.7% in the MMF group and 0% in the AZA group (P = .015). There were no bacterial or fungal infections observed in the 2 groups. MMF dose per body weight was significantly lower among patients with AR than those without AR (25.1 vs 35.6 mg/kg; P = .026). There were no differences in MPA PK parameters between patients with and without viral infections. CONCLUSIONS: Patients treated with MMF required less treatment for AR, however, there were no significant differences. MMF dose per body weight may play an important role in the occurrence of AR. Although virus infections occurred in recipients treated with MMF, MPA PK did not influence the infectious complications after renal transplantation.

Adult↗
PubMed2005

'Scirrhous' type hepatocellular carcinomas: a special reference to expression of cytokeratin 7 and hepatocyte paraffin 1.

AIMS: 'Scirrhous' hepatocellular carcinoma (scirrhous HCC) is extremely rare and its characteristics remain unclear. We investigated the clinicopathological and immunohistochemical features of scirrhous HCC, compared with those of ordinary hepatocellular carcinoma (ordinary HCC). METHODS AND RESULTS: We compared the clinicopathological and immunohistochemical features of 20 resected cases of scirrhous HCC with those of 69 resected cases of ordinary HCC. Scirrhous HCC was characterized by its gross and histological findings, such as a higher proportion of contiguous multinodular type tumours, the absence of a complete fibrous capsule around the tumour, the absence of tumour necrosis and highly preserved portal tracts in the tumour. The immunohistochemical results revealed a significantly higher expression of cytokeratin 7 and a significantly lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC (P<0.0001, respectively). There were no significant differences in proliferative activity and survival curves between the patients with scirrhous HCC and those with ordinary HCC. CONCLUSION: Scirrhous HCC has several particular gross, histological and immunohistochemical features. In particular, we would like to emphasize the greater immunohistochemical expression of cytokeratin 7 and lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC.

Adenocarcinoma, Scirrhous↗
PubMed2004

Gluteal muscular and sciatic nerve metastases in advanced urinary bladder carcinoma: case report.

We present a case of gluteal muscular and sciatic nerve metastases from urinary bladder carcinoma. T2-weighted magnetic resonance images demonstrated diffuse swelling and an increase in the signal of the right gluteus maximus muscle without destruction of the original arrangement of muscular fibers. Further, remarkable thickening of the right sciatic nerve showing a relatively hypointense signal was detected. Postcontrast T1-weighted images showed strong enhancement of these structures. Fine-needle aspiration biopsy with ultrasonographic guidance confirmed metastatic carcinoma cells in the right gluteal muscle and the sciatic nerve. These radiologic findings may represent a rare pattern of metastasis from urinary bladder carcinoma.

Adenocarcinoma↗
PubMed2004

Serum sex steroid hormone levels and polymorphisms of CYP17 and SRD5A2: implication for prostate cancer risk.

Polymorphism of the steroid hormone-related genes might affect life-long androgen exposure, thus altering a risk of prostate cancer incidence. To evaluate the effect of the polymorphisms of CYP17 and SRD5A2 on serum steroid hormone levels, the 164 male Japanese cohort were tested for serum hormone levels and the genotype of the polymorphisms of CYP17 (T-C base substitution in the promoter region) and SRD5A2 (V89L). The linear trends across the CYP17 genotypes in serum-free testosterone and androstenedione levels were found, suggesting the importance of the polymorphism of CYP17 in determining the circulating androgen levels.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2003

p16 Gene transfer increases cell killing with abnormal nucleation after ionising radiation in glioma cells.

It is well established that cells synchronised at the G1-S phase are highly radiosensitive. In this study, p16-null human glioma cell lines were induced into G1 cell cycle arrest by adenovirus-mediated p16 gene transfer, and examined for radiation-induced cell killing. Clonogenic analysis and trypan blue extraction test showed that the p16 gene transfer enhanced radiation-induced cell killing in p16-null glioma cell lines. TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism. Gimsa staining demonstrated that irradiation alone or Ax-mock infection plus irradiation results in a slight increase in the frequency of cells with abnormal nucleus, compared to unirradiated uninfected or Ax-mock infected cells. However, Ax-hp16 or Ax-hp21 infection alone modestly increased the frequency of cells with abnormal nucleus (especially bi- and multinucleation), and 4-Gy irradiation of Ax-hp16 or Ax-hp21 infected cells substantially enhanced this frequency. These results suggest that there exists some unknown interaction between radiation and p16 in cytoplasm/membranes, which decreases cytokinesis and promotes abnormal nucleation. Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

Adenoviridae↗
PubMed2003

Quantitation of bovine macrophage colony-stimulating factor in bovine serum by ELISA.

We established an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of bovine macrophage colony-stimulating factor (M-CSF) and used it to measure the serum M-CSF levels in bovine fetuses and calves. The average serum M-CSF level was 2.7+/-1.5 ng/ml in 39 calves under 100 days old, and 1.8+/-0.8 ng/ml in 15 cattle between 101 and 418 days old. Fetal sera samples (n = 6) prepared from cattle between 150 and 280 days of gestational age had a higher average level of M-CSF (8.8+/-1.4 ng/ml). Alteration in serum M-CSF levels in each individual calf was also measured. The serum levels of M-CSF in calves at 0-1 day after birth ranged from 0.52 to 7.3 ng/ml. During the period 113-125 days after birth, serum levels were around 1.4+/-0.39 ng/ml. Although serum M-CSF levels generally decreased as the age of calves advanced, differences among individuals, especially among newborn calves, were observed.

Age Factors↗
PubMed2003

Gene expression of type I collagen in neoplastic chondrocytes.

In the present examination, we detected type I collagen mRNA in neoplastic chondrocytes in osteochondromas, typical benign bone neoplasms. We believe that the cells involved in >chondroid bone< appearing in osteochondromas temporally express cartilage phenotypes and then change directly into bone-forming cells that survive in the >chondroid bone< until the tissue is resorbed and remodelled into true bone tissue.

Adolescent↗
PubMed2003

Dopant-pair structures segregated on a hydrogen-terminated Si(100) surface.

Novel atomic structures on a H-terminated Si(100)-(2x1)-H surface were found using scanning tunneling microscopy (STM). The structures are distinguishable only from Si dimers in empty-state STM images. They were observed on arsenic- and phosphorus-doped substrates, but not on boron-doped substrates. Surface density of these structures was found to be proportional to the dopant density in the substrate. First-principles calculations clarify that they are consisting of dopant pairs that are segregated from the bulk material. Hydrogen atoms attached to the dopant pair are found to flip between two positions on the surface due to a quantum effect.

Journal Article↗
PubMed2002

Localization of matrix proteins of hard tissue in osteochondromas.

We examined 10 cases of osteochondroma by means of histopathological, histochemical and immunohistochemical techniques. The surface of the masses was covered with a cartilage tissue showing positive immunohistochemical reaction for collagen type 2, and the deep region was composed of spongy bone, showing positive immunohistochemical reaction for collagen type 1 and osteocalcin. Between the cartilage and spongy bone, which is a metaphysis-like region, a chondroidal pattern appeared in the matrix of hypertrophy cartilage. In these regions, both type 1 (and osteocalcin) and 2 collagens were immunohistochemically detected. Although there is still no direct evidence, we believe that the cells involved in so-called "chondroid bone" temporally express cartilage phenotypes and then transform directly into bone-forming cells that survive in the chondroid bone until the tissue is resorbed and remodeled. Our examination results suggest that bone formation in osteochondromas, at least in some regions, occurs through transchondroid bone formation.

Adolescent↗
PubMed2002

Type II citrullinaemia (citrin deficiency) in a neonate with hypergalactosaemia detected by mass screening.

Type II citrullinaemia (CTLN2) is an adult- or late childhood-onset liver disease characterized by a liver-specific defect in argininosuccinate synthetase protein. The enzyme abnormality is caused by deficiency of the protein citrin, which is encoded by the SLC25A 13 gene. Until now, however, few cases with SLC25A13 mutations have been reported in children with liver disease. We describe an infant who presented with neonatal hepatitis in association with hypergalactosaemia detected by neonatal mass screening. DNA analysis of SLC25A13 revealed that the patient was homozygous for a IVS11+1G>A mutation. This case suggests that SLC25A13 mutant should be suspected in neonatal patients with hypergalactosaemia of unknown cause.

Citrullinemia↗
PubMed2002

[Specific features of p53 protein induction after ionizing radiation in cells of patients with Nijmegen breakage syndrome].

Synthesis of p53 and WAF1 (p21) proteins was studied in cells of patients with Nijmegen breakage syndrome (NBS) and of patients with ataxia telangiectasia (AT), as well as in normal cells with respect to their response to ionizing radiation (IR). In the NBS cells, the p53 protein was progressively accumulated with increasing radiation dose and reached the maximum 2 h after exposure to radiation at a dose of 5 Gy. The amount of p53 protein was consistently lower than that in normal cells, which was correlated with low content of the WAF1, the protein regulated by p53 at the level of transcription. Suboptimal induction of p53 observed in NBS cells was also characteristic of the AT cells, though the quantitative parameters of the protein synthesis in AT cells were intermediate relative to those in normal and NBS cells. In four NBS lines, the time schedule of p53 synthesis was similar to that observed in normal cells, whereas in AT cells, induction of p53 was significantly delayed as compared to control. In response to irradiation, the amount of p53 protein synthesized in patients with AT and NBS was significantly lower than that in normal cells. The results obtained, as well as the previously published medical and genetic evidence, suggest that the two diseases are of different origin and different genes are responsible for their development.

Ataxia Telangiectasia↗
PubMed2001

Real-time observation of a single DNA digestion by lambda exonuclease under a fluorescence microscope field.

A fluorescence microscopy technique has been developed to visualize the behavior of individual DNA and protein molecules. Real-time direct observation of a single DNA molecule can be used to investigate the dynamics of DNA-protein interactions, such as the DNA digestion reaction by lambda exonuclease. In conventional methods it is impossible to analyze the dynamics of an individual lambda exonuclease molecule on a DNA because they can only observe the average behavior of a number of exonuclease molecules. Observation of a single molecule, on the other hand, can reveal processivity and binding rate of an individual exonuclease molecule. To evaluate the dynamics of lambda exonuclease, a stained lambda DNA molecule with one biotinylated terminal was fixed on an avidin-coated coverslip and straightened using a d.c. electric field. Microscopic observation of digestion of a straightened DNA molecule by lambda exonuclease revealed that the DNA digestion rate was approximately 1000 bases/s and also demonstrated high processivity.

Avidin↗
PubMed2001

Post-cultured development of basic electrophysiological properties of spinal neurons obtained from rat embryo.

Basic electrical profiles of cultured neurons are modified by multiple factors, such as cell growth, differentiation and cell damage from the isolation procedure. In the present study, we assessed development of electrophysiological properties of rat spinal neurons over the late embryonic and early postnatal period in a neuron-enriched culture. After recovery from acute damage within 2 days after plating, the input conductance and amplitudes of voltage-gated Na(+) and K(+) currents increased parallel to the increase in the cell capacitance. Whether this depended on the period or the growth of the cell area was estimated by normalizing the parameters with the cell capacitance. The input conductance per unit area, the membrane time constant and the Na(+) current density remained constant for two weeks. However, densities of two types of outward K(+) currents, an A-current and a delayed rectifier, required 3--5 days to reach the maximum, although neither thresholds for activation nor sensitivities to blockers (TEA and 4AP) altered. The hyperpolarizing shift of the resting membrane potential became stabilized within 6--8 days, suggesting that the development of the K(+) currents underlay the shift. These results show that passive electrical properties and voltage-gated currents of rat spinal neurons in the neuron-rich culture differ in temporal patterns of development but stabilize at the latest within a week, corresponding to the day of birth.

Animals↗
PubMed2001

Combined immunodeficiency, chromosomal instability, and postnatal growth deficiency in a Japanese girl.

We report on an 11-year-old Japanese girl with combined immunodeficiency and chromosomal instability. She had postnatal growth deficiency and microcephaly, preaxial polydactyly of the left hand, and susceptibility to infections. Immunological studies showed marked lymphocytopenia (around 500/ll), reduced lymphocyte response to various mitogens, and reduced or absent serum IgA, IgG, and IgM. Cell biological studies of her primary skin fibroblasts demonstrated spontaneous chromosome aberrations and radiation hypersensitivity. The combination of immunodeficiency, chromosomal instability, and radiation hypersensitivity as seen in the girl is present in both ataxia-telangiectasia and Nijmegen breakage syndrome. Ataxia-telangiectasia was excluded because of differences in clinical features and laboratory data. Likewise, Nijmegen breakage syndrome is unlikely to be the case because the characteristic face, hyperpigmented spots, and mental retardation present in the syndrome were missing in the girl. Sequence analysis of a Nijmegen breakage syndrome responsible gene, NBS1, revealed no mutations. A normal NBS1 product was also demonstrated by immunoblot analysis using an anti-NBS1 antibody. We propose that the disorder in the girl represents a new combination of combined immunodeficiency and chromosomal instability.

Child↗
PubMed2001

Structural characteristics of the N-glycans of two isoforms of prostate-specific antigens purified from human seminal fluid.

Prostate-specific antigen (PSA) is a glycosylated chymotrypsin-like serine protease and is found mainly in prostatic tissue and seminal fluid. We purified two forms of PSA (PSA-A and PSA-B) from human seminal fluid with pI values of approx. 7.2 and approx. 6.9, respectively. To characterize the N-glycans of the two isoforms, the sugar chains were liberated by hydrazinolysis followed by N-acetylation, and derivatized with 2-aminobenzamide. Both PSA-A and PSA-B contained mono- and disialylated sugar chains, although PSA-B had a much higher content of the latter. After removal of sialic acid residues by sialidase digestion, mono- and biantennary N-glycans and three outer chain moieties (Galbeta1-4GlcNAcbeta1-, GlcNAcbeta1-, GalNAcbeta1-4GlcNAcbeta1-) were found in both samples. However, the ratios of each N-glycan were different. These results indicate that PSA-A and PSA-B differ not only in their sialic acid contents, but also in their outer chain features.

Carbohydrate Sequence↗
PubMed2001

The forkhead-associated domain of NBS1 is essential for nuclear foci formation after irradiation but not essential for hRAD50[middle dot]hMRE11[middle dot]NBS1 complex DNA repair activity.

NBS1 (p95), the protein responsible for Nijmegen breakage syndrome, shows a weak homology to the yeast Xrs2 protein at the N terminus region, known as the forkhead-associated (FHA) domain and the BRCA1 C terminus domain. The protein interacts with hMRE11 to form a complex with a nuclease activity for initiation of both nonhomologous end joining and homologous recombination. Here, we show in vivo direct evidence that NBS1 recruits the hMRE11 nuclease complex into the cell nucleus and leads to the formation of foci by utilizing different functions from several domains. The amino acid sequence at 665-693 on the C terminus of NBS1, where a novel identical sequence with yeast Xrs2 protein was found, is essential for hMRE11 binding. The hMRE11-binding region is necessary for both nuclear localization of the complex and for cellular radiation resistance. On the other hand, the FHA domain regulates nuclear foci formation of the multiprotein complex in response to DNA damage but is not essential for nuclear transportation of the complex and radiation resistance. Because the FHA/BRCA1 C terminus domain is widely conserved in eukaryotic nuclear proteins related to the cell cycle, gene regulation, and DNA repair, the foci formation could be associated with many phenotypes of Nijmegen breakage syndrome other than radiation sensitivity.

Amino Acid Sequence↗