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T Inui

Publications and source records attributed to T Inui.

At least 73 records · Page 4Linked to original sources

Clinical, pathological, and genetic features of limb-girdle muscular dystrophy type 2A with new calpain 3 gene mutations in seven patients from three Japanese families.

We report on the clinical, pathological, and genetic features of 7 patients with limb-girdle muscular dystrophy type 2A (LGMD2A) from three Japanese families. The mean age of onset was 9.7+/-3.1 years (mean+/-SD), and loss of ambulance occurred at 38.5+/-2.1 years. Muscle atrophy was predominant in the pelvic and shoulder girdles, and proximal limb muscles. Muscle pathology revealed dystrophic changes. In two families, an identical G to C mutation at position 1080 the in calpain 3 gene was identified, and a frameshift mutation (1796insA) was found in the third family. The former mutation results in a W360R substitution in the proteolytic site of calpain 3, and the latter in a deletion of the Ca2+-binding domain.

Age of Onset↗

Frequent alterations of cell-cycle regulators in astrocytic tumors as detected by molecular genetic and immunohistochemical analyses.

Alterations of CDKN2A, RB, and cyclin D1 genes and expression of their products in astrocytic tumors were studied using a combination of molecular genetic and immunohistochemical assays. In addition, the association of gene status with clinical outcome was evaluated. Alterations of CDKN2A and RB gene in 30 lesions were analyzed by single-strand conformation polymorphism of polymerase chain reaction (PCR-SSCP), direct sequencing, and Western blotting. Methylation of the CDKN2A promoter was detected by methylation-specific PCR. Immunohistochemistry was applied to determine the expression of gene products in tumors from 94 patients for whom clinical outcome was also evaluated. Analyses of the CDKN2A gene revealed 12 homozygous or hemizygous deletions, one mutation in exon 1, and three methylations in the promoter. Expression of p 16 protein was not detected in 18 of 30 cases. RB mutations leading to loss of expression of the pRb were found in four (13%) cases, and six were immunohistochemically negative for this protein. Overexpression of cyclin D1 was obtained in 51 (54%) of 94 cases. Patients with pRb-negative tumors had a significantly greater risk of earlier death than those with p16 and cyclin D1 alterations, Both p16 and pRb immunohistochemistry provides useful complementary information and may provide valuable predictive information in screening. The biological consequences of deregulating individual components along cell control pathways are unequal, perhaps reflecting their hierarchical roles in the G1 checkpoint.

Adolescent↗

Genetic variations in recurrent astrocytic tumors detected by restriction landmark genomic scanning.

The genetic mechanisms associated with recurrence of advanced astrocytic tumors are poorly understood. We therefore analyzed 24 biopsy specimens from 12 patients with a recurrent astrocytic tumor by a two-dimensional gel electrophoresis method, termed restriction landmark genomic scanning (RLGS). Four spot changes were commonly present in the primary astrocytomas, indicating that the corresponding gene alterations were early events in the development of this tumor type. Altered spots were more frequent and of different distribution in recurrent tumors than in the primary astrocytomas. In particular, specifically increased intensity for spots on chromosomes 9-12 and 18 were observed in the secondary tumors, suggesting a relation with recurrence. The same spot changes observed in primary tumors were also found in the respective secondary lesions but with strikingly different densities in some cases, suggesting increased genetic instability. The altered segments provide important candidate regions for the search for genes involved in events leading to progression and more malignant recurrent tumors.

Astrocytoma↗

Cerebral revascularization using omentum and muscle free flap for ischemic cerebrovascular disease.

BACKGROUND: Indirect cerebral revascularization has been generally accepted in the management of brain ischemia in moyamoya disease. We performed indirect cerebral revascularization by using omental flap and muscle flap techniques for the treatment of ischemic cerebrovascular disease. METHODS: Ten patients with ischemic cerebrovascular disease including three with adult moyamoya disease underwent this procedure (omental flap on eight sides and muscle flap on five sides). The muscle used for the flap was the serratus anterior muscle on two sides and shaved latissimus dorsi muscle on three sides. Angiography and cerebral blood flow studies were performed in all patients preoperatively and postoperatively. All patients demonstrated severely impaired cerebrovascular reserve capacity due to occlusive disease. RESULTS: There was one patient each with perioperative death and intracranial infection following omental flap loss, and two patients had perioperative strokes. The average follow-up period was 23.2 months. Of the nine surviving patients, all eight except for the one with flap loss had good outcome with complete resolution of neurologic episodes. CONCLUSIONS: It is concluded that this method seems to be effective in selected patients with ischemic cerebrovascular disease.

Adult↗

Genomic aberrations in renal cell carcinomas detected by restriction landmark genomic scanning.

In order to reveal and characterise genetic events occurring in renal tumorigenesis, samples of sporadic renal cell carcinomas (RCCs) were examined using restriction landmark genomic scanning (RLGS), an electrophoretic separation technique which detects gene amplification and deletion. We were able to find two fragments frequently amplified and 10 others commonly showing reduced signal intensity within the 16 tumour samples analysed. These altered spots were located on chromosomes 2, 3, 9-12, 16, 17 and 18 according to chromosomal assigned RLGS. A subset of reduced fragments appeared to be correlated to tumour type and were located within a new chromosomal region, suggesting genetic specificity within the process of renal carcinogenesis.

Aged↗

Hospital participation in community partnerships to improve health.

BACKGROUND: The core business of hospitals now requires, for both competitiveness and quality improvement reasons, that hospitals move beyond their physical and conceptual walls to form community partnerships. THE HOSPITAL'S ROLE AS A PARTNER IN COMMUNITY-BASED HEALTH IMPROVEMENT SYSTEMS: Hospitals, as organizations that are significant health care, social, and economic institutions in their communities, should play a leading role in mobilizing resources for such community-level health improvement efforts. MOVING OUTSIDE THE WALLS TO IMPROVE QUALITY: Three examples of extending hospital efforts into the community demonstrate that improvement of a problem involving hospital care can derive from a collaborative, community-based activity. In Boston, infection control--once a standard, strictly in-house procedure--has been forced by altered patterns of hospital use to become a largely community-based process. In Chicago, a variety of health care providers and community representatives have worked effectively to reduce mortality and morbidity in a single disease (asthma) model. In Akron, Ohio, Lifelink program hospitals, working together with community agencies and groups in a door-to-door neighborhood program, improved the effectiveness of prenatal care and the quality of birth outcomes. CONCLUSION: Efforts to work with community groups to improve health status should not be simply an optional do-good endeavor, as they have often been in the past, but rather an essential part of quality improvement and good business practice. Marketplace incentives will increasingly reward hospitals that are able to form successful community partnerships.

Boston↗

Genomic alterations in oral squamous cell carcinoma cell lines detected by two-dimensional gel analysis.

To initially analyze the genomic abnormalities in human oral squamous cell carcinoma, DNA extracted from each of four oral carcinoma cell lines (Ca9-22, HO-1-u-1, HSC-2, KB) was examined using restriction landmark genomic scanning (RLGS), a method especially conducive to detection of amplifications and rearrangements of genomic DNA. Isolated cell line and normal oral epithial DNAs were sequentially cleaved with specific restriction enzymes, radiolabelled and separated in two-dimensional gel electrophoreses. Thirteen distinct fragments were commonly amplified in the oral cancer cell lines, six of which were evident in all samples. These results suggest genetic alterations characteristic of oral squamous cell carcinogenesis.

Carcinoma, Squamous Cell↗

Late-onset unilateral renal dysfunction combined with non-insulin-dependent diabetes mellitus and bronchial asthma following allogeneic bone marrow transplantation for acute lymphoblastic leukemia in a child.

We report a child with T cell acute lymphoblastic leukemia who developed late-onset multiple complications after allogeneic bone marrow transplantation from an HLA-matched sibling. The preparative regimen consisted of total body irradiation (TBI, 12 Gy), splenic irradiation (6 Gy) and cytosine arabinoside (3 g/m2 x 10). Splenic irradiation was added because of persistent splenomegaly in spite of intensive chemotherapy. He developed bronchial asthma 1 1/2 years post transplant. He presented with microhematuria and proteinuria 4 1/2 years post-transplant, which were due to unilateral left renal dysfunction. He developed type II, non-insulin-dependent diabetes mellitus 8 years post-transplant. A biopsy from the left kidney was not compatible with diabetic nephropathy. All these complications appear to be independently related to BMT, particularly TBI and/or splenic irradiation.

Adolescent↗

Pharmacokinetic properties and oral bioavailabilities of difloxacin in pig and chicken.

1. Pharmacokinetic properties of difloxacin have been studied in pig and chicken after intravenous and oral administration. 2. The serum concentrations of difloxacin in pig and chicken after intravenous administration were best described by a two-compartment open model, giving distribution half-lives of 0.50 and 0.66 h and elimination half-lives of 7.92 and 4.10 h for pig and chicken respectively. The steady-state distribution volumes were 1.70 and 3.06 l/kg for pig and chicken respectively. 3. After oral administration of 5 mg/kg to pig and chicken, the serum concentrations reached maximal levels of 3.61 and 0.96 microg/ml respectively at 1.25 and 1.40 h. The elimination half-lives were 11.8 and 7.35 h for pig and chicken respectively. 4. The bioavailabilities of difloxacin were calculated as 93.7 (pig) and 86.9% (chicken).

Administration, Oral↗

Increase of thyroid stimulating activity in Graves' immunoglobulin-G by high polyethylene glycol concentrations using porcine thyroid cell assay.

Cyclic adenosine monophosphate (cAMP) production during a 5-hour incubation using porcine thyroid cells (PTC) was stimulated significantly more by polyethylene glycol (PEG) 22.5% precipitated fractions (ppt frs) than by PEG 12.5% ppt frs from almost all Graves' sera. However, the thyrotropin (TSH) binding inhibition (TBI) activities of the PEG 12.5% and 22.5% ppt frs using porcine thyroid membranes were similar, and did not change in the 5-hour incubation. When the PEG 12.5% ppt fr from Graves' serum and the PEG 22.5% ppt fr from normal human serum (NHS) were coincubated, cAMP production was also stimulated as much as by the PEG 22.5% ppt fr from Graves' serum. When purified thyroid stimulating antibody (TSAb)-immunoglobulin G (IgG) and the PEG 22.5% ppt fr from NHS were coincubated, increased cAMP production was also observed, whereas bovine thyrotropin (bTSH) did not produce this effect. When purified TSAb-IgG and PEG solutions were coincubated, maximum increases in cAMP production (approximately 10-fold) with 5% PEG were found, whereas no increase was observed using bTSH. The stimulatory effect of high PEG concentrations on thyroid stimulating activity was observed by TSAb-IgG in salt-free or salt-containing medium (<0.15 mol/L NaCl concentration) but not by either TSAb-IgG conjugated to protein A-sepharose 4B or the inactivated TSAb-IgG by the treatment of 70 degrees C for 10 minutes. No stimulatory action by PEG was found with the thyroid stimulating substances such as GTPgammaS, forskolin, or pituitary adenylate-cyclase activating polypeptide (PACAP). The increased thyroid stimulating activity of Graves (IgG) at high PEG concentrations suggests the existence of some factors influencing the ability of TSAb to stimulate thyroid cells, although the exact mechanism remains to be clarified.

Animals↗

Clusters of basic amino acids in midkine: roles in neurite-promoting activity and plasminogen activator-enhancing activity.

The removal of N-terminally located clusters of basic amino acids (N-tail) or C-terminally located clusters of basic amino acids (C-tail) from the midkine (MK) molecule severely reduced its neurite-promoting activity. However, experiments involving chemically synthesized MK derivatives revealed that the roles of the N-tail and C-tail were mostly indirect ones, i.e. they probably maintain the steric arrangements of the N-terminal and C-terminal halves. In particular, the C-domain, which is the C-terminal half devoid of the C-tail, retained considerable neurite-promoting activity when it was uniformly coated on a dish. The removal of the N-tail or C-tail also reduced the enhancing activity of plasminogen activator (PA) in aortic endothelial cells, although the effect was lower. There are two heparin-binding sites in the C-domain, Clusters I and II. A mutation in Cluster I [R78-->Q] affected the PA-enhancing activity only slightly, and a mutation in Cluster II [K83K84-->QQ] abolished the activity, while both mutations are known to reduce the neurite-promoting activity moderately. Therefore, the two heparin-binding sites in the C-domain play different roles in these two activities. Indeed, heparin exhibited different effects on these two activities. We also observed that intact MK was required for ordered neurite-promotion along the path of MK; one possible interpretation of this is that the N-terminal half is necessary for the stability of the molecule. Furthermore, K76 and K99 were found to be required for the secretion of MK; i.e. mutants in which one of these K residues was changed to Q were produced in the host cells, but not found in the medium.

Amino Acid Substitution↗

Chemical synthesis of dendrotoxin-I: revision of the reported structure.

Dendrotoxin I (DTX-I) is a 60-residue peptide from the venom of the black mamba snake Dendroaspis polylepis, which binds to neuronal K+ channels. The structure reported previously for DTX-I was synthesized for the first time by a solution procedure. The synthetic product was confirmed to have the correct primary and disulfide structure determined by peptide mapping, sequence analysis and mass measurements. Comparison of synthetic DTX-I with the natural one by high-performance liquid chromatography and capillary zone electrophoresis, as well as by sequence analysis, revealed that the Asn residue at position 12 in the synthetic peptide was Asp in the natural product. Synthesis of DTX-I with Asp at position 12 gave a peptide identical with the natural product in all aspects. NMR analysis of synthetic [Asn12]- and [Asp12]-DTX-I also supported our findings that the Asn residue at position 12 in the DTX-I molecule should be revised as Asp. [Asn12]- and [Asp12]-DTX-I had very similar binding affinities when tested against radiolabeled dendrotoxin binding to rat brain synaptosomal membranes.

Amino Acid Sequence↗

Paracrine endothelin signaling in the control of basal cell proliferation in guinea pig tracheal epithelium.

Immunofluorescent analyses revealed distinct cellular/subcellular localization of endothelin (ET) receptors and ET-1 in the epithelial cell layer of guinea pig trachea. ETA was expressed predominantly in the basal cells. ETB was expressed predominantly in the ciliated columnar cells and was polarized at the apical side of the cell body within the cells. Anti-ET-1-immunoreactive cytoplasmic granules were contained in the secretory cells that were scattered throughout the epithelial layer. Cell proliferation assays with immersion cultures of differentially plated cells (basal cell-enriched, non-basal cell-enriched and mixed cell cultures) indicated the presence of paracrine ET-1 signaling pathways that transmit both positive and negative effects on the basal cell proliferation. Direct activation of ETA expressed on the basal cells caused enhancement of their growth, whereas that of ETB expressed on the ciliated columnar cells caused suppression of the basal cell growth. The latter effect was transmitted by nitric oxide whose production was stimulated by ETB activation. Furthermore, blockade of either ETA or ETB compromised the epithelial cell layer formation under the air-interphase culture, which indicates the dependence of tracheal epithelial remodeling on a balance between the positive and negative effects of ET-1 on the basal cell growth.

Animals↗

Solution structure of midkine, a new heparin-binding growth factor.

Midkine (MK) is a 13 kDa heparin-binding polypeptide which enhances neurite outgrowth, neuronal cell survival and plasminogen activator activity. MK is structurally divided into two domains, and most of the biological activities are located on the C-terminal domain. The solution structures of the two domains were determined by NMR. Both domains consist of three antiparallel beta-strands, but the C-terminal domain has a long flexible hairpin loop where a heparin-binding consensus sequence is located. Basic residues on the beta-sheet of the C-terminal domain form another heparin-binding site. Measurement of NMR signals in the presence of a heparin oligosaccharides verified that multiple amino acids in the two sites participated in heparin binding. The MK dimer has been shown to be the active form, giving signals to endothelial cells and probably to neuronal cells. We present a head-to-head dimer model of MK. The model was supported by the results of cross-linking experiments using transglutaminase. The dimer has a fused heparin-binding site at the dimer interface of the C-terminal domain, and the heparin-binding sites on MK fit the sulfate group clusters on heparin. These features are consistent with the proposed stronger heparin-binding activity and biological activity of the dimer.

Amino Acid Sequence↗

Retinoblastoma protein expression and MIB-1 correlate with survival of patients with malignant astrocytoma.

BACKGROUND: Regulatory coupling of cell proliferation and apoptosis is suggested by recent findings with regard to certain tumors, such as the finding of tumor resistance to anticancer therapy caused by inhibition of apoptosis. The processes leading to apoptosis appear to be regulated by a variety of oncogenes and tumor suppressor genes. In the current study, the relation between apoptosis and expression of retinoblastoma protein (pRB) was assessed in 50 primary anaplastic astrocytomas (AAs) and 46 recurrent tumors in the same patients as the primary tumors after macroscopic total surgical resection and chemoradiotherapy. METHODS: Apoptotic cells were identified by the in situ 3'-end labeling technique. Proliferative potential, pRB expression, and p53 expression were evaluated immunohistochemically using anti-Ki-67 (MIB-1), anti-pRB, and anti-p53 antibodies, respectively. The prognostic value of these biologic markers in AA patients undergoing treatment was also evaluated. RESULTS: The mean apoptotic index (AI) was 0.91 +/- 0.70% for specimens obtained at the initial surgery and 2.32 +/- 1.71% for those obtained at recurrence. There was no apparent correlation between the AI and the MIB-1 staining index (MI) in primary AAs, whereas significantly higher AI and MI were observed in recurrent pRB negative cases than in their pRB positive counterparts. The survival of patients with AAs showing a high MI and negative pRB immunostaining was significantly shorter than in the other cases. Neither the size of the apoptotic fraction nor the p53 expression in primary tumor correlated with the overall survival. CONCLUSIONS: The clinical outcome of patients with AA may be associated with aberrant pRB function and increased proliferative activity rather than an inability of tumor cells to undergo apoptosis.

Adult↗

Dimerization of midkine by tissue transglutaminase and its functional implication.

Midkine (MK), a retinoic acid-inducible growth/differentiation factor, serves as a substrate for tissue transglutaminase (Kojima, S. , Muramatsu, H., Amanuma, H., and Muramatsu, T. 1995. J. Biol. Chem. 270, 9590-9596). Upon incubation with transglutaminase MK forms multimers through cross-linkages. Here, we report the following results. 1) Heparin potentiated the multimer formation by MK. 2) The N- and C-terminal half domains each formed a dimer through the action of transglutaminase. 3) Gln42 or Gln44 in the N-terminal half and Gln95 in the C-terminal half served as amine acceptors in the cross-linking reaction, as judged from the incorporation of putrescine into whole MK or each half domain, and the competitive inhibition of the cross-linking by MK-derived peptides containing Gln residue(s). The strongest inhibition was obtained with Ala41-Pro51. 4) This peptide abolished the biological activity of MK to enhance the plasminogen activator activity in bovine aortic endothelial cells. The inhibition was limited against the MK monomer, and not seen against the MK dimer, separated by gel filtration chromatography. These results suggest that dimer formation through transglutaminase-mediated cross-linking is an important step as to the biological activity of MK.

Animals↗

Cathepsin K antisense oligodeoxynucleotide inhibits osteoclastic bone resorption.

Cathepsin K is a recently identified cysteine protease which is abundantly and selectively expressed in osteoclasts. To evaluate the contribution of cathepsin K to bone resorption processes, we investigated the effect of cathepsin K antisense phosphothiorate oligodeoxynucleotide (S-ODN) on the bone-resorbing activity of osteoclasts. Rabbit osteoclasts were cultured on dentine slices for 24 h in the presence or absence of antisense S-ODN in a medium containing 100 nM TfxTM-50, polycationic liposome, as a carrier of the S-ODN. Uptake of the S-ODN by osteoclasts was confirmed microscopically using fluorescein-labeled S-ODN. The treatment with antisense significantly decreased the amount of cathepsin K protein in osteoclasts. The antisense inhibited the osteoclastic pit formation in a concentration-dependent fashion. At 10 microM the antisense reduced the total pit number and area and average pit depth by 46, 52, and 30%, respectively. The sense and mismatch S-ODNs, which were used as negative controls, had no effect on either the cathepsin K protein level or the pit formation. A nonspecific cysteine protease inhibitor, E-64, also reduced pit formation in a concentration-dependent manner with maximum reductions at 1 microM of 46, 48, and 35% in the above pit parameters. The inhibitory effect of the antisense almost equal to that of E-64 demonstrates that cathepsin K is a cysteine protease playing a crucial role in osteoclastic bone resorption.

Animals↗