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T Takagi

Publications and source records attributed to T Takagi.

At least 469 records · Page 26Linked to original sources
PubMed1993

[CT finding of right diaphragmatic rupture due to blunt trauma--subhepatic hemothorax].

Owing to the poor detectability of the anatomic location of diaphragm on the parallel plane of computed tomography (CT), capability of CT to predict traumatic ruptured diaphragm has been debated in several reports. A specific hematoma (subhepatic hemothorax) adjacent to the posterior attachment of the right diaphragm was identified on CT. The finding originated from herniated liver that migrated to the posterior thoracic wall as a result of gravity, to separate the hemothorax in the supine position. This was surgically proven in two patients after blunt traumatic accident. The finding is useful in predicting right diaphragmatic rupture on CT study. The formation of subhepatic hemothorax, its differential diagnosis and a brief review of diaphragmatic rupture are discussed.

Adult↗
PubMed1993

Presence of a novel primary response gene ST2L, encoding a product highly similar to the interleukin 1 receptor type 1.

In the course of studying the ST2 gene, which was initially found to be expressed specifically at the G0/G1 transitional state in BALB/c-3T3 cells and was one of the primary response genes, we found another ST2-related mRNA, designated as ST2L, in serum-stimulated BALB/c-3T3 cells in the presence of cycloheximide. Nucleotide sequence analysis of the cloned ST2L cDNA revealed that it had an open reading frame encoding a polypeptide of 567 amino acids. A 5' region (1,028 nucleotides) of ST2L cDNA was identical with the ST2 cDNA, and a unique 3' region encoded a putative transmembrane domain of 24 amino acids and a cytoplasmic domain of 201 amino acids. The ST2 gene product is highly similar to the extracellular portion of IL-1 receptors type 1 and type 2, and the ST2L gene product shows a marked similarity with entire IL-1 receptor type 1.

3T3 Cells↗
PubMed1993

Change in oligomeric structure of solubilized Na+/K(+)-ATPase induced by octaethylene glycol dodecyl ether, phosphatidylserine and ATP.

Membrane-bound Na+/K(+)-ATPase purified from dog kidney was solubilized with octaethylene glycol dodecyl ether (C12E8), and the resultant solubilized enzyme was chromatographed on a TSKgel G4000SWXL or G3000SWXL column equilibrated with elution buffers containing various ligands affecting oligomerization of the enzyme. Weight-averaged molecular weight (Mw) values for the main protein components eluted were estimated by low-angle laser light-scattering photometry. With increasing concentration of C12E8 included in the elution buffer from 0.1 to 5 mg/ml, the Mw decreased from 230,000 to 153,000, indicating that C12E8 induced dissociation of the enzyme. In contrast, the Mw of the protein component increased up to 1.44.10(6) as the concentration of phosphatidylserine (PS) added to the elution buffer containing a fixed concentration of 0.3 mg/ml C12E8 was increased to 120 micrograms/ml. The association and/or aggregation were reversible by removal of the PS by rechromatography. Addition of PS to the elution buffer also allowed the solubilized enzyme to exhibit ATPase activity comparable to that of the membrane-bound enzyme during passage through the column. This was also the case with phosphatidylglycerol (PG) and phosphatidylinositol, but not with phosphatidylcholine or phosphatidylethanolamine. The specific refractive index increment (dn/dcp) of the solubilized enzyme was increased by addition of exogenous PG or PS, strongly suggesting that the phospholipid became bound to the enzyme, and that it induced association of the enzyme. The association induced by PS was inhibited by ATP and ADP, but not AMP. The concentrations for half-maximal inhibition were 0.44 mM for ATP and 0.88 mM for ADP. The PS-induced associated enzyme isolated by chromatography in the presence of 120 micrograms/ml PS was dissociated by ATP with K0.5 of 0.16 mM. The dissociating effect of C12E8, ATP and ADP and the associating effect of PS on the solubilized enzyme are consistent with the reports that C12E8 mimics the effect of regulatory ATP at the low-affinity site on the conformational transition from E2 to E1, and that phospholipids are essential for the reverse transition from E1 to E2. The results can be explained by assuming that the enzyme takes the form of a loosely associated diprotomer in the E1 state and a tightly associated one in the E2 state.

Adenosine Triphosphate↗
PubMed1993

Effect of salt concentration of buffer on the binding of sodium dodecyl sulfate and on the viscosity behavior of the protein polypeptide derived from bovine serum albumin in the presence of the surfactant.

The complex between SDS and a protein polypeptide derived from bovine serum albumin was characterized with respect to binding of SDS and viscosity behavior. The amount of bound SDS increased from 1.0 to 2.2 g/g with increase of the buffer concentration from 10 to 220 mM. A logarithmic plot of the amount of bound SDS against the buffer concentration gave a linear relation like in the plot where the number of SDS molecules constituting a spherical micelle of SDS is plotted similarly. The increase in the buffer concentration up to 25 mM, from 25 to 100 mM and beyond 100 mM, was accompanied by a sharp rise, monotonic decrease and levelling-off of the intrinsic viscosity in the respective region. In the region 45-175 mM, a linear relation was found between the intrinsic viscosity and reciprocal square root of the buffer concentration. The observed changes can be interpreted as follows: (1), the electrostatic repulsion between charges introduced by the bound SDS caused the initial increase; (2), shielding of the charges as the result of ion condensation with further increase in ionic strength caused the viscosity drop and subsequent levelling-off. The characteristics of the plots are consistent with the necklace model proposed previously for such complexes in which SDS is bound to a protein polypeptide forming micelle-like clusters and which behave like a flexible polyelectrolyte (Shirahama, K., Tsujii, K. and Takagi, T. (1974) J. Biochem. 75, 309-319).

Buffers↗
PubMed1993

Characteristics of anti-type II collagen antibody binding to articular cartilage.

OBJECTIVE: Previous studies suggested that it was possible to characterize the intact surface of articular cartilage by probing it with antibodies against matrix macromolecules. The present studies were undertaken to investigate type II collagen (CII) epitope availability on the intact surface of articular cartilage. METHODS: Normal bovine, rabbit, and human cartilage specimens were used to measure binding of anti-CII antibodies to the articular and cut surfaces of cartilage. Antisera were raised against the material obtained after brief extraction of the cartilage surface with 4M guanidine solution. RESULTS: Anti-CII did not bind to the intact surface of rabbit articular cartilage when compared with control rat sera, but did bind significantly to the cut surface. With normal human articular cartilage, the cut surfaces bound approximately 4 times as much anti-CII antibody as the intact articular surfaces. These findings suggested that the CII epitopes are normally protected by the superficial cartilage layer. In experiments carried out to characterize this layer, binding of anti-CII antibodies was unchanged after exhaustive washing of bovine or rabbit cartilage with phosphate buffered saline or 1M NaCl solution, whereas it was significantly increased after brief exposure to 4M guanidine solution or after incubation with neutrophil elastase. No restoration of the protection of CII epitopes in guanidine-treated cartilage could be achieved by incubation with undiluted normal bovine synovial fluid; however, 8-day culture of elastase-treated cartilage explants resulted in partial restoration of protection of the CII epitopes. Rat and rabbit antisera raised against the cartilage surface material extracted with 4M guanidine contained antibodies that bound to the cartilage surface. By Western blotting, rat antibodies identified 50-65-kd protein bands present in the guanidine extract, but not present either in the material obtained from brief digestion of cartilage with neutrophil elastase or in synovial fluid. The rabbit antisera identified a broad 70-95-kd band. Exposure of elastase-treated cartilage to the guanidine-extracted material resulted in a partial decrease of anti-CII antibody binding. CONCLUSION: These results suggest that CII on intact cartilage is protected from antibody binding, and that the protective material is at least partly proteinaceous in nature, is unlikely to be derived from synovial fluid, is noncovalently bound to the underlying intercellular matrix, and is synthesized by resident chondrocytes. Further characterization of the protective material may provide important information on the mechanisms of early cartilage damage in inflammatory arthritis.

Animals↗
PubMed1993

Electrophoretic light scattering.

Under a microscope, electrophoretic mobilities of visible particles can be determined in a free solution without any boundary or zonal separation. Electrophoretic light scattering based on the Doppler velocimetry can be taken as a nanometer-scale version of the above traditional electrophoresis. An electrophoretic light scattering apparatus was developed to enable mobility determination of proteins and surfactant micelles which have been outside the range of the electrophoresis.

Electrophoresis↗
PubMed1993

Detection of hepatitis C virus genome in human serum by multi-targeted polymerase chain reaction.

A multi-targeted "hemi-nested" PCR (M-PCR) assay in which the primer pairs derived from the 5' non-coding (5'NC) and the nonstructural protein 3 (NS3) regions of HCV genome were concurrently used for amplification in order to compare the sensitivity and specificity of polymerase chain reaction (PCR) with different primer pairs in detecting hepatitis C virus (HCV) genome. Sera from patients with virus-associated liver diseases were examined for the presence of HCV RNA by the M-PCR method following reverse transcription to cDNA. The amplified products derived from both the 5'NC and the NS3 regions were detected in 28 (70%) of the 40 HCV RNA-positive samples. However, 12 samples (30%) were devoid of the signal of NS3-derived product. Sensitivity tests using serial dilutions of HCV RNA revealed that the 5'NC-derived band was still detectable in the 10(5)-fold diluted sample by the M-PCR method, yet the NS3-derived band could hardly be detected in the 10(4)-fold diluted sample. Thus, as previously demonstrated by a single-targeted "nested" PCR assay, the present study using the M-PCR assay has clearly shown that the 5'NC-derived primers are more sensitive and specific than the NS3-derived primers in detecting HCV RNA.

BK Virus↗
PubMed1993

Congenital inclusion cysts over the anterior fontanel in Japanese children: a study of five cases.

Congenital inclusion cysts over the anterior fontanel are rare in children in Asia and Europe. However, recent evidence of an increase in cases in both areas has been presented. In the period from 1980 to 1989, four patients with a dermoid cyst and one with an epidermoid cyst have undergone total excision in our department. Including the previously reported Japanese cases, the number of recorded Japanese cases is now 15, the number of Asian cases thus corresponding to the number in Europe. Although these lesions are unlikely to have intracranial extensions, noninvasive neuroimaging methods such as computed tomography and magnetic resonance imaging are recommended for preoperative investigations.

Child↗
PubMed1993

Effect of prostaglandin D2 on the femoral bone mineral density in ovariectomized rats.

We studied the effects of prostaglandin D2 (PGD2) on the femoral bone mineral density (BMD) and other related parameters in ovariectomized (OVx) and sham-operated rats. BMD was measured in vivo by dual energy X-ray absorptiometry (DXA) for the period of 36 days or 112 days after operation. When 9- or 10-week-old rats were used at the time of operation, the femoral BMD increased during these periods. Ovariectomy resulted in a marked suppression of this steady increase in BMD at both proximal and distal ends of the femur. Subcutaneous administration of a slow-release preparation of PGD2 on days 1 and 21 not only prevented the ovariectomy-induced suppression of BMD, but also augmented the steady increase in BMD of the sham-operated rats. When medication was started on day 70, the depressed rate of increase in BMD was restored to the control level. Serum calcitonin (CT) and parathyroid hormone (PTH) levels were not affected by either ovariectomy or by PGD2 administration. Body weight and bone length were increased, but uterine weight was decreased by ovariectomy. PGD2 administration showed no effects on these parameters. There was a significant increase in the fasting level of urinary hydroxyproline excretion after ovariectomy, and PGD2 administration had no significant effect on this parameter either. These results indicate that the prevention of osteopenia in OVx rats and the increase in BMD in sham-operated and post-OVx rats by PGD2 administration are due to its stimulatory effect on bone formation.

Absorptiometry, Photon↗
PubMed1993

Estimation of left ventricular myocardial elasticity and viscosity by a thick-walled spherical model.

The authors measured the transfer function (TF) of the left ventricle (LV) in an isolated canine preparation. Here TF indicates the ratio of induced vibration in LV to input vibration when an external mechanical oscillation is applied. TF had a single peak the frequency of which changed from 40 Hz to 80 Hz when LV pressure (LVP) increased from 6 mm Hg to 96 mm Hg. A mathematical model was formulated to estimate the viscoelasticity of the spherical shell. This model was constructed of the material points, elastic components which connected all the material points, and viscous components placed in series with elastic components. Theoretical TF can be computed if the viscoelastic values are given. The value of viscoelasticity at which the theoretical TF best fitted the experimental TF was considered to be the viscoelasticity of the model. The validity of this approach was verified using a silicone spherical shell. The estimated myocardial elasticity was 40 kPa when LVP was 6 mm Hg, 160-170 kPa when LVP was 96 mm Hg and was approximately proportional to LVP, whereas viscosity showed small change. The inclination of elasticity was consistent with previous reports. These results proved that myocardial elasticity can be estimated by analysing the transfer function of the left ventricle.

Animals↗
PubMed1993

A deductive database system PACADE for analyzing 3-D and secondary structures of protein.

We have developed a deductive database system PACADE for analyzing 3-D and secondary structures of protein. The PACADE system consists of a relational database created from Protein Data Bank and a deductive engine DEE based on logic programming. It has the following features: (1) The system has an inference mechanism. This means by which users can easily write and check biological hypotheses using logical and declarative rules instead of procedural programs. (2) The relational database of the PACADE system stores data on both 3-D and secondary structures of protein. The integration of this two level structure makes feasible an abstract representation of the protein structure. We describe herein the design, functions, and implementation of this PACADE system.

Computer Graphics↗
PubMed1993

Development of the Overlapping Oligonucleotide Database and its application to signal sequence search of the human genome.

We have developed ODS (Overlapping Oligonucleotide Database for Signal Sequence Search)--the first relational database that integrates information on biological features into the search for signal sequences. In existing biological sequence databases, even relational ones, retrieving nucleotide sequences based on their biological features involves much labour and time or even the development of a new program. GenBank sequence data, including FEATURES records, are organized into three relational tables in ODS. Nucleotide sequences are transformed into overlapping oligonucleotides in order to facilitate the signal sequence search rapidly without the need for specific alignment programs. This transformation leads to a one-to-one correspondence between the nucleotide sequence and its biological feature. The signal sequence search by ODS is done in SQL queries and ODS obviates the need for molecular biologists to write computer programs. The application of ODS to searches of promoter regions revealed putative cis-acting elements and basic statistical analyses of occurrences of oligonucleotides showed interesting findings concerning the 'cg' dinucleotide.

Computer Systems↗
PubMed1993

Molecular conformation of porcine amelogenin in solution: three folding units at the N-terminal, central, and C-terminal regions.

Circular dichroism (CD) studies were conducted to gain a better insight into the conformation of amelogenins, which were isolated from developing enamel of piglets. The intact porcine amelogenin and its degraded products were purified chromatographically. The 25-residue peptide corresponding to the segment at the C-terminus was synthesized. CD spectra of these samples were measured at pH 5.0-5.3 in the temperature range between 4 and 90 degrees C. The most remarkable finding was that the CD spectrum of the intact amelogenin was accounted for by the sum of the spectra of the three fragments at the N-terminal, central, and C-terminal regions, supporting the hypothesis that the structure of the whole protein consists of discrete folding units. Furthermore, low-angle laser light scattering analysis provided evidence that the 20 kDa amelogenin, the most abundant extracellular matrix protein in forming enamel tissue, exists in a monomeric form at pH 5.3 and 25 degrees C. It was tentatively concluded that the N-terminal region contains beta-sheet structures, while the spectral characteristics of the C-terminal region are similar to those of a random coil conformation. The conformation of the central region was characterized by a strong negative ellipticity at 203 nm, although its nature remains to be defined.

Amelogenin↗
PubMed1993

Structure of 29-kDa protein from ascidian (Halocynthia roretzi) body wall muscle.

Preparations of thin filament from ascidian (Halocynthia roretzi) body wall muscle were found to be contaminated with large amounts of an unknown protein which, when purified, migrated to 29 kDa on SDS-PAGE and was thus named HR-29. To elucidate its physiological function, we have determined the primary structure of HR-29 by peptide and cDNA sequence analysis. Genomic sequence analysis showed that HR-29 is divided to four exons by three introns. It is composed of 251 amino acid residues and the N-terminal Ser is blocked by an acetyl group. The N-terminal domain of 150 residues is hydrophilic, and from residue 36 to 92 there are three similar repeated sequences of 19 residues. The N-terminal domain showed no significant sequence homology with other proteins. On the other hand, the C-terminal domain of 100 residues has homology with those of small heat-shock proteins and alpha-crystallin of lens protein. HR-29 is thought to be a fusion protein of two different origins. Recently alpha B-crystallin was identified in skeletal muscle and suggested to be a myofibril-stabilizing protein [Atomi, T. et al. (1991) J. Biochem. 110, 2360-2364]. Thus, HR-29 may also be a myofibril-stabilizing protein, as suggested by the sequence similarity of the C-terminal domain with alpha-crystallin, although the origin and role of the N-terminal domain are not clear.

Amino Acid Sequence↗
PubMed1993

Purification of water-soluble bone-inductive protein from bovine demineralized bone matrix.

The water-soluble fraction containing bone-inductive activity was purified from guanidine-hydrochloride extracts of bovine demineralized bone. The purification steps include ultrafiltration, dialysis, affinity chromatography on heparin-Sepharose and gel chromatography on Sephacryl S-200. Combination of these steps was proven to be an effective and rapid method for the purification of this protein. Subcutaneous implantation of the water-soluble protein with type I collagen was carried out in the thorax of rats. When alkaline phosphatase activity and calcium content in implants were used as indices for purification, the water-soluble bone-inductive protein was purified > 600-fold according to the enzyme activity and 64-fold according to the calcium content. A morphological examination revealed that many chondrocyte and osteoblast cells were seen in the location of the implanted material. Sodium dodecyl sulfate/gel electrophoresis of the protein produced in this way under non-reducing conditions revealed four protein bands of 18, 16, 14 and 11 kDa. None of the separated bands had any biological activity. This result suggests that the water-soluble bone-inductive activity depends on an associated form of various proteins in the range of 18 to 11 kDa.

Alkaline Phosphatase↗
PubMed1993

Rational estimation of the QSAR (quantitative structure-activity relationships) descriptors sigmaS0, and their applications for medicinals now available.

Rational estimation of the descriptor sigmaSo, representing the dispersion and repulsion energies in the van der Waals interaction for both aliphatic and aromatic moieties, enabled us to present the descriptors of several important medicinals now available. In this work, the fundamental rule for the estimation of the descriptor for a substrate having a variety of binding modes and the correction value deltaSo necessary for aliphatic heterocycle formation are confirmed, and the descriptors for several important moieties are established according to the concept of quantitative structure-activity relationship analogy. Furthermore, several kinds of herbicides, antiinflammatory agents, hypocholesterolemics, analgesics, sympathetic stimulants, and antipsychotics are concerned in this work.

Analgesics↗
PubMed1993

Serological survey for Borrelia burgdorferi infection in cattle in southern Hokkaido.

By means of the enzyme-linked immunosorbent assay (ELISA), antibodies to Borrelia burgdorferi were examined in 970 cattle from southern Hokkaido, Japan. The seropositivity rate in the cattle less than 2 years old differed significantly from that in those 3 years old or more. A seasonal variation was also observed in the rate of seropositivity to B. burgdorferi. High levels of anti-B. burgdorferi antibody were detected even in sera from a healthy group of cattle, indicating that there are likely to be many inapparent cases of B. burgdorferi infection. This article discusses the syndromes associated with Lyme borreliosis and addresses the issues of diagnosis and treatment in animals.

Animals↗