Search PubMed⌕ Search

Biomedical subjects

N Inoue

Publications and source records attributed to N Inoue.

At least 109 records · Page 6Linked to original sources
PubMed2000

Primary resective shortening followed by distraction osteogenesis for limb reconstruction: a comparison with simple lengthening.

Resective distraction osteogenesis is a new approach to treat segmental diaphyseal bone defects by primary limb shortening and secondary distraction osteogenesis from the same site. A rabbit model was introduced to compare the bone-regeneration characteristics of this technique with those of simple lengthening procedures. Twenty-four skeletally mature New Zealand White rabbits were divided into two equal groups. In the test group, limbs were lengthened after a 10-mm segmental diaphyseal bone resection and limb shortening. In the control group, a simple subperiosteal osteotomy for limb lengthening was performed without resection. New bone formation was evaluated mechanically, radiologically, histomorphometrically, and densitometrically. Bone bridging occurred in all animals. Normalized mechanical values for the newly reconstructed tibiae demonstrated similar torsional stiffness (71+/-3.3 compared with 71+/-8.2%; p = 0.95) and strength (64+/-5.3 compared with 68+/-7.3%; p = 0.66) in the two groups. The average normalized callus diameter was significantly greater in the test group than in the control group (p < 0.01). The remodeling index calculated from densitometry, however, showed a significantly less progressed stage of remodeling in the test group (p < 0.05). Histomorphometric analysis of the callus center supported this finding, showing significantly lower values for trabecular thickness (p < 0.05) and total bone volume (p < 0.01) in the test group. The results demonstrated the possibility of new bone formation after resection and monofocal shortening. This suggests a new therapeutic option to treat diaphyseal segmental bone defects.

Absorptiometry, Photon↗
PubMed2000

Circulating autoantibodies against purified colonic mucin in ulcerative colitis.

To clarify the role of colonic mucin in the autoimmune process of ulcerative colitis, circulating antibodies against human colonic mucin were investigated. Purified colonic mucin, obtained from human colonic mucosa by gel filtration, using a Bio-Gel A-1.5-m column and CsCl equilibrium density gradient, was divided into soluble mucin (S-mucin) secreted extracellularly and membranous mucin (M-mucin) binding to cell membrane. Sodium dodecylsulfate polyacrylamide gel electrophoresis and Western blotting analysis showed that antibodies in the serum samples of some patients with ulcerative colitis recognized purified S- and M-mucin of >180-kD. By enzyme-linked immunosorbent assay (ELISA), anti-mucin antibodies were detected in 11 of 60 patients with ulcerative colitis (18%). In contrast, the antibodies were not detected in 22 patients with Crohn's disease. The titers of antimucin antibodies against S-mucin and M-mucin were not different in each patient. By ELISA using mucin in which the sugar chains were destroyed by neuraminidase or NaIO4 treatment, it was demonstrated that anti-mucin antibodies recognized the epitopes of either the sugar chain or the core protein exposed through destruction of the sugar chains. We then investigated the relationship between anti-mucin antibodies and the patients' clinical features. Anti-mucin antibodies were detected in 6 of 15 patients with chronic continuous type ulcerative colitis (40%) and in 5 of 26 patients with relapsing-remitting type (19%), but there was no antimucin antibody-positive serum in patients who had had only one attack without any relapse. These results suggest that anti-mucin antibodies could be a disease marker for ulcerative colitis and that immunological abnormalities in colonic mucin contribute to the persistence of colonic mucosal inflammation.

Autoantibodies↗
PubMed2000

Expression of SAG-1 of Toxoplasma gondii in transgenic mice.

We describe the expression of SAG-1 cDNA in B6C3F1 mice by microinjecting a 3.3 kbp DNA fragment, consisting of the cytomegalovirus enhancer-chicken beta-actin hybrid promoter and SAG-1 into the pronucleus of a fertilized egg at the one-cell stage. Offspring derived from this microinjection were analyzed for the integration and functional expression of the SAG-1 transgene. Steady-state expressions of both the mRNA for SAG-1 and SAG-1 protein product were detected in the brain, thymus, spleen and liver. Approximately 50% of F1 and F2 progeny inherited the SAG-1 transgene from SAG-1 transgenic mice in Mendelian fashion. These results indicated that SAG-1 transgenic lines were established. Transgenic mice harboring the SAG-1 gene will contribute a critical tool of defining the molecular mechanisms of SAG-1 in pathogenesis and host immune response.

3T3 Cells↗
PubMed2000

Identification of facultatively alkaliphilic Bacillus sp. strain YN-2000 and its fatty acid composition and cell-surface aspects depending on culture pH.

Facultatively alkaliphilic Bacillus sp. strain YN-2000 was isolated from an indigo ball. Although the strain has been extensively investigated as a representative strain of alkaliphilic bacillus, its taxonomic position is not yet known. Morphological, biochemical, and physiological characteristics and chemotaxonomic properties indicated that the strain was closely related to Bacillus cohnii; this was confirmed by the high homology of the 16S rRNA sequence and the construction of a phylogenetic tree on the basis of the 16S rRNA sequence and DNA-DNA relatedness data. Strain YN-2000 contained a larger amount of unsaturated fatty acids compared with Bacillus subtilis and the obligate alkaliphile, Bacillus alcalophilus, regardless of its culture pH. When the cells were grown at pH 10, the unsaturated fatty acid content and anteiso-/iso-branched fatty acid ratio became lower than those at pH 7. This result suggests that membrane fluidity decreases when the cells are grown at pH 10 compared to those of pH 7. In the cells of strain YN-2000 grown at pH 10, the cell-surface aspect was rougher, the cell shape was longer, and the cell-surface layer was thicker compared with those of the cells grown at pH 7. The cell-surface structural change might be related to adaptation to an alkaline environment.

Alkalies↗
PubMed2000

Inhibition of endothelium-dependent arterial relaxation by oxidized phosphatidylcholine.

Formation of oxidized phosphatidylcholine (ox-PC), oxidatively fragmented phosphatidylcholine (PC) containing a short-chain and/or polar oxidative residue at the sn-2 position, in the process of LDL oxidation as well as its existence in atherosclerotic lesions has been demonstrated. To clarify the pathophysiological role of ox-PC in the vascular reactivity, we investigated the effects of various ox-PCs on the isometric tensions in rabbit thoracic aortas. Ox-PCs, which were produced upon oxidation of sn-2 polyunsaturated fatty acid (PUFA)-containing PCs, dose-dependently inhibited endothelium-dependent relaxation (EDR) evoked by acetylcholine or substance P. On the other hand, neither native PUFA-containing PCs nor an oxidative product of monounsaturated fatty acid-containing PC showed an inhibitory effect. None of ox-PCs affected endothelium-independent relaxation to nitroglycerin. The PC-headgroup fraction, but not the oxidized fatty acids fraction, was responsible for the inhibition of EDR by ox-PC. EDR was reduced by 2-(5-oxovaleroyl)-PC, one of the secondary oxidative products of PCs that contains a short chain aldehydic residue at the sn-2 position, but not by PC hydroperoxide, the primary oxidative product. Although the possibility could not be completely ruled out that lysophosphatidylcholine rather than ox-PC may be responsible for inhibitory effects on EDR, these results suggest a novel vascular activity of ox-PCs generated from sn-2 PUFA-containing PCs which may be implicated in the pathophysiology of vascular tone.

Acetylcholine↗
PubMed2000

Importance of OGTT for diagnosing diabetes mellitus based on prevalence and incidence of retinopathy.

Study was made on the necessity and importance of the oral glucose tolerance test (OGTT) for diagnosing diabetes mellitus based on prevalence and incidence of diabetic retinopathy. Subjects were 12208 persons undergoing OGTT between 1965 and 1997. The prevalence of retinopathy was significantly elevated with FPG>/=126 and 2-h PG>/=198 mg/dl. The incidence of retinopathy was 15-30/10000 person-years (PY) with FPG<125, but with FPG of 126-139 it was significantly higher (69/10000 PY) and at 140-199 mg/dl it was elevated to 139/10000 PY. Subjects were classified at initial test into FPG<110, 110-125, 126-139, and >/=140 and further into 2-h PG<200 and >/=200 mg/dl for comparison with the incidence of retinopathy. Even with the same FPG, the incidence was two- to threefold higher with 2-h PG>/=200 mg/dl, indicating that 2-h PG was highly associated with the incidence of retinopathy. As for IFG, the prevalence of diabetes as defined by 2-h PG>/=200 in the OGTT increased with elevated FPG, and 33.7% of IFG cases showed 2-h PG>/=200 mg/dl. Based on the prevalence and incidence of retinopathy, we conclude that 126 mg/dl FPG is an appropriate cut-off level, and the OGTT is important for diagnosing mild diabetes mellitus.

Adolescent↗
PubMed2000

Gastropod arginine kinases from Cellana grata and Aplysia kurodai. Isolation and cDNA-derived amino acid sequences.

Arginine kinase (AK) was isolated from the radular muscle of the gastropod molluscs Cellana grata (subclass Prosobranchia) and Aplysia kurodai (subclass Opisthobranchia), respectively, by ammonium sulfate fractionation, Sephadex G-75 gel filtration and DEAE-ion exchange chromatography. The denatured relative molecular mass values were estimated to be 40 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isolated enzyme from Aplysia gave a Km value of 0.6 mM for arginine and a Vmax value of 13 micromole Pi min(-1) mg protein(-1) for the forward reaction. These values are comparable to other molluscan AKs. The cDNAs encoding Cellana and Aplysia AKs were amplified by polymerase chain reaction, and the nucleotide sequences of 1,608 and 1,239 bp, respectively, were determined. The open reading frame for Cellana AK is 1044 nucleotides in length and encodes a protein with 347 amino acid residues, and that for A. kurodai is 1077 nucleotides and 354 residues. The cDNA-derived amino acid sequences were validated by chemical sequencing of internal lysyl endopeptidase peptides. The amino acid sequences of Cellana and Aplysia AKs showed the highest percent identity (66-73%) with those of the abalone Nordotis and turbanshell Battilus belonging to the same class Gastropoda. These AK sequences still have a strong homology (63-71%) with that of the chiton Liolophura (class Polyplacophora), which is believed to be one of the most primitive molluscs. On the other hand, these AK sequences are less homologous (55-57%) with that of the clam Pseudocardium (class Bivalvia), suggesting that the biological position of the class Polyplacophora should be reconsidered.

Amino Acid Sequence↗
PubMed2000

Dissecting and manipulating the pathway for glycosylphos-phatidylinositol-anchor biosynthesis.

The pathway for glycosylphosphatidylinositol-anchor biosynthesis consists of at least 10 reaction steps. Many of the genes encoding the enzymes and regulators involved in this pathway have been recently cloned and their products characterised. These studies have revealed the common and also different characteristics of glycosylphosphatidyl-inositol biosynthesis enzymes in different organisms, leading to the development of species-specific inhibitors of the pathway.

Acetylglucosamine↗
PubMed2000

Propiverine-induced Parkinsonism: a case report and a pharmacokinetic/pharmacodynamic study in mice.

PURPOSE: We present a case report of propiverine-induced Parkinsonism. We previously reported the induction of catalepsy by amiodarone, aprindine and procaine, which possess a diethylaminomethyl moiety and demonstrated selective blockade of dopamine D2 receptors by these drugs in mice. We hypothesized that drugs possessing a diethylaminomethyl structure may generally induce Parkinsonism and/or catalepsy. METHODS: Thus, we performed a study to examine whether oxybutynin, pentoxyverine and etafenone, as well as propiverine, induce catalepsy in mice. RESULTS: The intensity of drug-induced catalepsy was in the order: haloperidol > etafenone > pentoxyverine > propiverine > oxybutynin. In vivo occupancy of dopamine D1, D2 and mACh receptors in the striatum was also examined. The in vitro binding affinities to the D1, D2 and mACh receptors in the striatum synaptic membrane were within the ranges of 2.4-140 microM, 380-4,200 nM, and 1.2-2,800 nM, respectively. CONCLUSIONS: These results support the idea that any drug possessing a diethylaminomethyl moiety may contribute to the induction of catalepsy, possibly by occupying dopamine receptors.

Animals↗
PubMed2000

Effects of chondroitin sulfate-C on articular cartilage destruction in murine collagen-induced arthritis.

The effects of chondroitin sulfate-C (CAS 25322-46-7, Chondroitin ZS Tab) on type II collagen (CII)-induced arthritis (CIA) in mice were evaluated. DBA/1J mice were immunized with bovine CII emulsified in Freund's complete adjuvant, followed by a booster injection 21 days later. Chondroitin sulfate-C at doses of 100, 300 and 1000 mg/kg was administered orally once daily beginning 14 days before initial immunization. An arthritis index and hind paw edema were examined from day 0 to day 49, when the mice were killed by ether anesthesia for histopathological examination. The delayed-type hypersensitivity (DTH) reaction, serum anti-CII antibody titer, and histopathologic characteristics of both synovitis and destruction of articular cartilage were analyzed. Both the arthritis index and the serum anti-CII antibody titer were reduced by treatment with chondroitin sulfate-C in a dose-dependent manner. Chondroitin sulfate-C (1000 mg/kg) significantly inhibited hind paw edema, synovitis and destruction of the articular cartilage, but not DTH reaction.

Animals↗
PubMed2000

Gaa1p and gpi8p are components of a glycosylphosphatidylinositol (GPI) transamidase that mediates attachment of GPI to proteins.

Many eukaryotic cell surface proteins are anchored to the membrane via glycosylphosphatidylinositol (GPI). The GPI is attached to proteins that have a GPI attachment signal peptide at the carboxyl terminus. The GPI attachment signal peptide is replaced by a preassembled GPI in the endoplasmic reticulum by a transamidation reaction through the formation of a carbonyl intermediate. GPI transamidase is a key enzyme of this posttranslational modification. Here we report that Gaa1p and Gpi8p are components of a GPI transamidase. To determine a role of Gaa1p we disrupted a GAA1/GPAA1 gene in mouse F9 cells by homologous recombination. GAA1 knockout cells were defective in the formation of carbonyl intermediates between precursor proteins and transamidase as determined by an in vitro GPI-anchoring assay. We also show that cysteine and histidine residues of Gpi8p, which are conserved in members of a cysteine protease family, are essential for generation of a carbonyl intermediate. This result suggests that Gpi8p is a catalytic component that cleaves the GPI attachment signal peptide. Moreover, Gaa1p and Gpi8p are associated with each other. Therefore, Gaa1p and Gpi8p constitute a GPI transamidase and cooperate in generating a carbonyl intermediate, a prerequisite for GPI attachment.

Acyltransferases↗
PubMed2000

Effects of high-temperature treatments on a thermophilic cyanobacterium Synechococcus vulcanus.

Effects of high-temperature treatments on a thermophilic cyanobacterium, Synechococcus vulcanus, were studied, and the following results were obtained. (1) Oxygen evolution and the PSII photochemical reaction were the most sensitive sites and started to be inactivated at temperatures slightly higher than the cultivating temperature. (2) The decrease in the fluorescence Fv value reflected the inactivation of the charge separation reaction of PSII as well as that of the oxygen evolution reaction. (3) The dark fluorescence level, Fo, showed an increase at around 70 degrees C, which was partially reversed by further incubation at 50 degrees C. This increase reflected the inactivation of PSII reaction centers and probably dissociation of phycobilisomes from the PSII reaction center complexes. (4) At higher temperatures, phycobiliproteins disassembled and denatured in a pH-dependent manner, causing a large Fo decrease. (5) Cell membranes became leaky to low-molecular-weight substances at around 72 degrees C. (6) Inhibition of growth of the cells was recognized when the cells were pretreated at temperatures higher than 72 degrees C. Reversibility of the high-temperature effects and relationship between viability of the cells and the degradation of the cell membranes are discussed.

Bacterial Proteins↗
PubMed2000

Reconstruction of complex cranial wounds with demineralized bone matrix and bilayer artificial skin.

Complex wounds involving loss of both cranium and scalp are difficult to reconstruct. Current solutions include both autogenous and alloplastic materials. Tissue engineering provides interesting alternatives for reconstruction of missing bone and soft tissue. Demineralized bone matrix and Integra, artificial bilayer skin substitute, have been used successfully to reconstruct bone and skin as isolated defects, but never in combination. This study investigates the possibility of using demineralized bone matrix in a gel carrier and Integra for combined cranial and scalp defects. The study was divided into two parts. In the first, demineralized bone matrix in the forms of Grafton Flex (n = 12) and Grafton putty (n = 12) was used to reconstruct 15-mm critical size cranial defects in female adult New Zealand White rabbits. In the control group (n = 6), the defect was left empty. The second part of the study investigated the use of Integra and Grafton Flex to reconstruct a 15-mm cranial defect with an overlying full-thickness scalp defect (n = 6). The first study revealed bony healing of the critical-size cranial defect with demineralized bone matrix. The second study demonstrated successful reconstitution of scalp and cranium with both demineralized bone matrix and Integra. We conclude that complex cranial defects involving bone and soft tissue may be successfully reconstructed with their tissue-engineered substrates, demineralized bone matrix (Grafton) and Integra artificial skin.

Absorptiometry, Photon↗
PubMed2000

Biomechanical evaluation of dual-energy X-ray absorptiometry for predicting fracture loads of the infant femur for injury investigation: an in vitro porcine model.

OBJECTIVE: The purpose of this study was to determine the ability of bone mineral density (BMD) measured by dual-energy x-ray absorptiometry (DXA) and geometry measured by biplanar x-ray to predict fracture mechanics in vitro in an immature femur model. DESIGN: Prospective analysis of radiographic and biomechanical data was performed. SETTING: In vitro experimentation. INTERVENTIONS: Bone geometry and DXA data were obtained before mechanical testing. Twenty-two porcine femora from males and females (age 3 to 12 months; body weight 3.6 to 7.0 kilograms) were fractured. Mechanical tests were performed on the diaphysis of the femora in two loading configurations: (a) three-point bending to simulate loads that result in transverse fractures; and (b) torsion to simulate twisting injuries that result in spiral fractures. MAIN OUTCOME MEASURES: Correlation of radiographic data with the experimentally determined bone strength. RESULTS: Three-point bending consistently resulted in transverse fractures. Femoral diaphysis BMD (mean, 0.304 grams per square centimeter; SD, 0.028 grams per square centimeter) strongly correlated (r2 = 0.938) to fracture load in bending. Load at failure ranged from 530 to 1,024 N (mean, 726 N; SD, 138 N), consistent with the findings of Miltner. Empirically derived strength parameters coupling BMD with geometry accurately predicted bending loads (r2 = 0.84, p < 0.001) and energy to failure (r2 = 0.88, p < 0.05). Torsional loading failed to generate spiral fractures consistently, resulting in either end plate or diaphyseal fractures. Load at failure for torsion ranged from 1,383 to 3,559 Newton-millimeters (mean, 2,703 Newton-millimeters; SD, 826 Newton-millimeters). Because of these inconsistent fracture results, empirical strength parameters for torsion could not be derived. CONCLUSION: BMD coupled with geometry is a strong predictor of bending fracture loads in the immature femoral diaphysis. A similar relationship could not be shown for torsion because of inconsistent failure results. This study represents an initial attempt at developing a methodology for predicting the strength of young bones from radiographic measures. Further research is required to establish this methodology and to show the necessary correlation with immature human bone.

Absorptiometry, Photon↗