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Biomedical subjects

K Ogata

Publications and source records attributed to K Ogata.

At least 397 records · Page 22Linked to original sources
PubMed1987

Tenosynovial fibroma arising from the posterior cruciate ligament.

In a 16-year-old girl, a locking and effusion of the left knee occurred without a history of any specific trauma. Arthroscopic examination of the knee revealed a soft tissue mass arising from the posterior cruciate ligament. The mass was completely excised, arthroscopically. The microscopic diagnosis was tenosynovial fibroma, a new entity reported by Chung and Enzinger in 1979. After a follow-up study of 20 months, the patient was asymptomatic.

Adolescent↗
PubMed1987

Effects of standard surgical procedures on the patellar blood flow in monkeys.

The effects of various surgical dissections on the patellar blood flow were studied in ten monkeys by the use of the hydrogen washout technique. The patellar blood flow was decreased to an average of 65% of the control value after an extensive medial parapatellar arthrotomy. When the infrapatellar fat pad was completely removed following extensive medial arthrotomy, the blood flow further decreased to an average of 49% of the control. When a lateral retinacular release with sacrifice of the lateral superior genicular artery was performed following the medial arthrotomy, the blood flow decreased to an average of 53% of the control. When a lateral release was combined with removal of the fat pad following the main medial arthrotomy, the patellar blood flow showed marked decrease to an average of only 17% of the control. The vascular anatomic study demonstrated that many vessels penetrate from the fat pad into the inferior pole of the patella. It is suggested that the lateral superior genicular artery and/or the fat pad should be carefully preserved to avoid ischemia of the patella during extensive procedures such as total knee arthroplasty.

Animals↗
PubMed1986

Cross-linking study on protein neighborhoods at the subunit interface of rat liver ribosomes with 2-iminothiolane.

Rat liver 80 S ribosomes were cross-linked with 2-iminothiolane. Proteins extracted from the cross-linked 80 S ribosomes were separated into 25 fractions by chromatography on carboxy methylcellulose. Each protein fraction was analyzed by diagonal polyacrylamide-sodium dodecyl sulfate gel electrophoresis. Eight pairs characteristic of 80 S ribosomes were detected which did not appear when isolated 40 S and 60 S subunits were cross-linked, and the cross-linked proteins were analyzed in similar manners. The cross-linked components were radioiodinated and then analyzed by two-dimensional gel electrophoresis, followed by autoradiography. Eight kinds of cross-links between 60 S subunit proteins and 40 S subunit proteins were identified as follows: SA30 (acidic protein with Mr 30,000)-LA33 (acidic protein with Mr 33,000), S2-LA33, S2-L11, S3a-L11, S4-L5, S25-L5, S4-L24 and S6-L24.

Animals↗
PubMed1986

Cross-linking study on localization of the binding site for elongation factor 1 alpha on rat liver ribosomes.

Complexes containing rat liver 80 S ribosomes, poly(uridylic acid), phenylalanyl-tRNA, elongation factor 1 alpha, and guanylyl(beta, gamma-methylene)-diphosphonate were prepared. Neighboring proteins in the complexes were cross-linked with the bifunctional reagent 2-iminothiolane. Proteins were extracted and then separated into 26 fractions by chromatography on carboxymethylcellulose. Each protein fraction was subjected to diagonal polyacrylamide-sodium dodecyl sulfate gel electrophoresis. Four cross-linked pairs containing elongation factor 1 alpha were on the vertical line below the diagonal. The ribosomal protein spot of each pair was cut out from the gel plate and labeled with 125I. The labeled proteins were extracted from the gel and identified by two-dimensional gel electrophoresis, followed by autoradiography. The following proteins of both 60 S and 40 S subunits were identified: L12, L23, L39, S23/S24, and S26, three proteins of which had been found to be cross-linked also to elongation factor 2 (Uchiumi, T., Kikuchi, M., Terao, K., Iwasaki, K., and Ogata, K. (1986) Eur. J. Biochem. 156, 37-44). These results afford direct evidence that both elongation factors interact with partially overlapping sites on rat liver ribosomes.

Animals↗
PubMed1986

Heterogeneity of factor IX BM. Difference of cleavage sites by factor XIa and Ca2+ in factor IX Kashihara, factor IX Nagoya and factor IX Niigata.

Abnormal factor IX was isolated from the plasma of a patient with hemophilia B Kashihara and two patients with hemophilia BM. The F.IX was purified to homogeneity by using monoclonal anti-F.IX-Sephrose, heparin-Sepharose and DEAE-Sephadex A-50 affinity chromatography successively. The isolated proteins have the same molecular weight and the same mobility on crossed immunoelectrophoresis as normal F.IX. The limited proteolysis of purified proteins was induced by F.XIa/Ca2+ or by RVV-X/Ca2+. A time course study showed that F.IX Nagoya seemed to be cleaved by neither F.XIa nor RVV-X, F.IX Kashihara was cleaved partially by F.XIa but not by RVV-X, and that F.IX Niigata was cleaved completely at the rate similar to normal F.IX, though the resultant product of F.IX Niigata did not show any F.IXa activity. These results favored the view that hemophilia B+ or BM is a heterogeneous disorder.

Antigens, Heterophile↗
PubMed1986

Cross-linking of elongation factor 2 to rat-liver ribosomal proteins by 2-iminothiolane.

Complexes containing rat liver 80S ribosomes treated with puromycin and high concentrations of KCl, elongation factor 2 (EF-2) from pig liver, and guanosine 5'-[beta, gamma-methylene]triphosphate were prepared. Neighboring proteins in the complexes were cross-linked with the bifunctional reagent 2-iminothiolane. Proteins were extracted and then separated into 22 fractions by chromatography on carboxymethylcellulose of which seven fractions were used for further analyses. Each protein fraction was subjected to diagonal polyacrylamide/sodium dodecyl sulfate gel electrophoresis. Nine cross-linked protein pairs between EF-2 and ribosomal proteins were shifted from the line formed with monomeric proteins. The spots of ribosomal proteins cross-linked to EF-2 were cut out from the gel plate and labelled with 125I. The labelled protein was extracted from the gel and identified by three kinds of two-dimensional gel electrophoresis, followed by autoradiography. The following proteins of both large and small subunits were identified: L9, L12, L23, LA33 (acidic protein of Mr 33000), P2, S6 and S23/S24, and L3 and L4 in lower yields. The results are discussed in relation to the topographies of ribosomal proteins in large and small subunits. Furthermore we found new neighboring protein pairs in large subunits, LA33-L11 and LA33-L12.

Animals↗
PubMed1986

Nucleotide sequence of cloned cDNA specific for rat ribosomal protein L35a.

A cDNA clone specific for rat ribosomal protein L35a, which is known to be a tRNA-binding protein, was isolated by hybrid-selected translation from a cDNA library made for 8-9-S poly(A)-rich RNA from regenerating rat liver. The nucleotide sequence of the cDNA was determined. It consists of one base pair from the 5' leading sequence, the entire coding sequence of 333 base pairs and 14 base pairs from the 3' trailing sequence. The primary structure of protein L35a was deduced from the nucleotide sequence. It consists of 109 amino acids with a molecular mass of 12422. The calculated amino acid composition is consistent with that reported for the hydrolysate of L35a. The amino acid sequence showed marked homology with the reported partial sequence of Xenopus leavis ribosomal protein L32, but not significant homology with Escherichia coli ribosomal proteins that bind to tRNA.

Amino Acid Sequence↗
PubMed1986

Idiopathic osteonecrosis of the first metatarsal sesamoid.

Four patients with histologically confirmed osteonecrosis of the first metatarsal sesamoid are presented. No patient was an athlete, nor recalled any noticeable trauma or significant stress as having occurred to the feet. No foot deformities or joint malalignments were found. Excellent results were obtained by excision of the affected sesamoid in all patients, after follow-up periods of 1 to 12 years. Microscopic findings were compatible with those seen in idiopathic osteonecrosis of the femoral head.

Adolescent↗
PubMed1986

Cerebral venous angioma of the pons: report of a case with pontine hemorrhage.

Cerebral venous angioma in the pons associated with pontine hemorrhage in a 39-year-old normotensive woman was identified with computed tomography and angiography. Venous angioma in the brain stem is usually silent and rarely found by chance at autopsy. Only a few cases have been clinically reported. Our report indicates that in unusual cases of intracerebral hemorrhage, vascular malformations should be suspected and scrutinized with radiologic examination including angiography.

Adult↗
PubMed1986

Blood flow of peripheral nerve effects of dissection, stretching and compression.

Blood flow rate of the peripheral nerve was measured using the hydrogen washout technique and the effects of dissection, stretching and compression were studied on blood flow of the rabbit sciatic nerve. Regional surgical dissections revealed that a proximal portion of the sciatic nerve receives its blood supply from gluteal vessels whereas a distal portion receives from popliteal vessels. Blood flow direction in the proximal half of the sciatic nerve in the thigh was found to be distal whereas in the distal half to be proximal. The longitudinal pathway appeared to be capable of compensating for local diminution of blood flow. The average stretching of more than 15.7% caused complete arrest of blood flow in the stretched nerve. The average stretching force at this point was 74 grams. Complete standstill of intraneural circulation was observed under compression of 50 to 70 mm Hg, or 60 to 80% of mean arterial pressure. These values of critical stretching and compression on the intraneural blood flow corresponds well with those previously reported by Lundborg, 1973; Rydevik, 1981).

Animals↗
PubMed1986

Effects of DNA and urea on the specificity for H1 histone of the neutral protease B partially-purified from rat liver chromatin.

A neutral protease, named protease B in the previous report (Tsurugi, K. & Ogata, K. (1982) J. Biochem. 92, 1369-1381), was partially purified from rat liver chromatin by gel filtration through Sepharose 6B followed by DE-Sephadex column chromatography. The proteolytic activity on total histones of the partially-purified protease B was increased about two fold by addition of DNA and again increased by further addition of 2 M urea. Analysis of the hydrolysed products showed that out of five species of histones, only H1 was degraded in the presence of an amount of DNA equivalent to the amount of histones, whereas core histones were also degraded in the absence or presence of one-tenth amount of DNA. Urea accelerated the selective degradation of H1 histone because H1 histone was preferentially degraded in the presence of even a low amount of DNA. In contrast, core histones became resistant to the protease B in the presence of DNA and/or urea. Heat-denatured DNA stimulated the degradation of H1 histone even in the absence of urea to almost the same extent that native DNA did in the presence of urea. Thus, protease B efficiently degrades H1 histone when its association with DNA is destabilized by either addition of urea or pretreatment of DNA with heat.

Animals↗
PubMed1986

Hemoglobin Sendagi (beta 42 Phe----Val): a new unstable hemoglobin variant having an amino acid substitution at CD1 of the beta-chain.

Hb Sendagi, a new unstable hemoglobin variant, was found in a Japanese male and his daughter, who have a moderate hemolytic anemia. The variant showed decreased stability upon heat and isopropanol precipitation tests. The variant did not separate from hemoglobin A by electrophoresis, but the abnormal beta-chain emerged ahead of the normal beta-chain on reverse-phase HPLC. Structural analyses revealed that the phenylalanine beta 42 (CD1), one of the critical amino acid residues in the heme pocket, had been replaced by valine. Oxygen equilibrium studies of the patient's hemolysates indicated that Hb Sendagi had a lowered oxygen affinity and a normal response to 2,3-diphosphoglycerate. Hb Hammersmith (beta 42 Phe----Ser) and Hb Louisville (Bucuresti) (beta 42 Phe----Leu) have previously been reported to have varying degrees of molecular instability and altered oxygen binding function. Hb Sendagi provides an additional model for elucidation of the role of the phenylalanine beta CD1 on the structure and function of hemoglobin.

Anemia, Hemolytic↗