Biomedical subjects

K Arao

Publications and source records attributed to K Arao.

9 recordsLinked to original sources

PubMed2001

Constituents of crinoidea. 2. Isolation and structure of the novel type gangliosides from the feather star Comanthus japonica.

Two novel type gangliosides CJP2 and CJP3 have been obtained from the feather star Comanthus japonica. On the basis of methylation linkage analysis combined with ammonolysis and other chemical and spectroscopic evidence, the chemical structures of CJP2 and CJP3 were determined to be alpha-9-O-Me-NeuGc-(2-->3)-inositolphosphoceramide and alpha-9-O-Me-NeuGc-(2-->11)-alpha-9-O-Me-NeuGc-(2-->3)-inositolphosphoceramide, respectively. These gangliosides are unique in that they are inositolphosphoceramide derivatives possessing sialic acid; such gangliosides have not previously been identified. The presence of 9-O-methyl-N-glycolyl-neuraminosyl residues is also unique in naturally occurring gangliosides.

Animals↗

PubMed2001

[Relationship between prothrombin time international normalized ratio and thrombo test (%)].

OBJECTIVES: The optimal therapeutic range for laboratory evaluation of oral anticoagulant therapy is now defined by the prothrombin time international normalized ratio (PT-INR). However, the thrombo test (TT), an alternative method to measure intensity of anticoagulation, is also currently used throughout Japan. The relationship between PT-INR and TT (%) has yet to be clarified. This study investigated the relationship between PT-INR and TT (%). METHODS: The PT-INR and TT (%) were simultaneously measured of 505 consecutive samples from patients treated with warfarin in our hospital. Fourteen functions were used for regression analyses: a fractional function (Y = a/X + b), a square root function (Y = aX0.5 + b), a natural logarithmic function (Y = a.lnX + b), a power series function (Y = aXb), a quotient function (Y = abX), and polynomial functions [Y = anXn + an - 1Xn - 1 +......+ a1X1 + b, (1 < or = n < or = 9)]. The results were confirmed by the same methods in 383 samples and 296 samples from another two laboratories. RESULTS: The power series function showed the most significant (p < 0.0001) and highest adjusted R2 (0.858) correlation, with a regression formula of TT (%) = e4.48 (PT-INR)-2.09 in our laboratory. Using the same analyses, the power series function also showed the most significant and highest adjusted R2 in samples from the other two laboratories. CONCLUSIONS: This study showed that a power series function is the most appropriate for expressing the relationship between PT-INR and TT (%) among the 14 functions. The function between PT-INR and TT (%) is mainly derived from the relationship between TT (%) and TT (sec). Both internal validity and external validity confirmed the relationship between PT-INR and TT (%).

Aged↗

PubMed2000

Santonin-related compound 2 inhibits the expression of ICAM-1 in response to IL-1 stimulation by blocking the signaling pathway upstream of I kappa B degradation.

Santonin-related compounds (SRCs) were synthesized from the starting material L-alpha-santonin and tested for the biological activity on the expression of intercellular adhesion molecule-1 (ICAM-1) in response to IL-1 stimulation on human adenocarcinoma cells. One of the bromoketone derivatives termed SRC2 [11S-2 alpha-bromo-3-oxoeudesmanno-13,6 alpha-lactone] strongly inhibited the ICAM-1 expression at an IC(50) value of 5.9 microM, whereas L-alpha-santonin itself was totally inactive up to 100 microM. The blockage of ICAM-1 expression by SRC2 was not due to the direct inhibition of de novo RNA and protein synthesis. The nuclear translocation of NF-kappaB subunit p65 was markedly prevented by SRC2. Moreover, I kappa B alpha degradation upon IL-1 stimulation was strongly inhibited by SRC2. These observations suggest that SRC2 blocks the IL-1 signaling pathway upstream of I kappa B degradation.

Biological Transport↗

PubMed2000

Congenital balloon digits in two neonates caused by constriction rings.

Balloon digits were found in two neonates with congenital constriction ring syndrome. The affected digits were the right long finger and right great toe. They were surgically treated at the age of 10 and 9 days, respectively. Morphologic improvement was dramatic after surgery. In cases with extensive enlargement, severe cyanosis, redness, and no subsidence of edema within several days after birth, early operative treatment may be necessary to maintain digit viability and prevent autoamputation due to circulatory embarrassment. It can also be helpful to prevent fibrosis of the subcutaneous tissue. Pathologic examination revealed marked proliferation of fibrous tissue and lymphatic vessels.

Constriction, Pathologic↗

PubMed1998

Purification, characterization and differentiation-dependent expression of a perchloric acid soluble protein from rat kidney.

We have recently reported the presence of a novel perchloric acid soluble protein in rat liver (PSP1) that inhibits cell-free protein synthesis in a rabbit reticulocyte system. While studying the perchloric acid soluble proteins from different tissues of rats, we found that the kidney protein cross-reacted with antibody against the PSP1. In this investigation, we have purified a perchloric acid soluble protein from the rat kidney and studied its characterization and expression. The protein extracted from the postmitochondrial supernatant fraction with 5% perchloric acid was purified by ammonium sulfate fractionation and CM-Sephadex chromatography. By immunoscreening with the rabbit antisera against the PSP1, we detected a cDNA that contained an open reading frame of 411 bp, encoding a 137 amino-acid protein with a molecular mass of 14,149 daltons. The deduced amino acid sequence was completely identical with that of PSP1 from rat liver. The perchloric acid soluble protein from rat kidney (K-PSP1) also inhibited cell-free protein synthesis in the rabbit reticulocyte lysate system in a different manner than RNase A. Immunohistochemistry showed that the expression of K-PSP1 increased from fetal 17th day to postnatal 4th week, and it remained almost the same until the 7th week of postnatal age. Furthermore, the expression of K-PSP1 in the kidney of the nephrotic rat model was shown to be differentiation dependent. On the other hand, the expression of K-PSP1 in renal tumor cells was downregulated as compared with intact tissue. These results suggest that the expression of K-PSP1 is regulated in a differentiation-dependent manner in the kidney.

Amino Acid Sequence↗

PubMed1995

Costunolide and dehydrocostus lactone as inhibitors of killing function of cytotoxic T lymphocytes.

Costunolide and dehydrocostus lactone were isolated from an extract of mokko (Saussurea lappa Clarke) as inhibitors of killing activity of cytotoxic T lymphocytes (CTL). Mokko lactone was also isolated as an inactive compound from the extract. The structure-activity relationship indicated that alpha-methylene-gamma-butyrolactone is required for the inhibitory effect. Costunolide markedly inhibited the granule exocytosis and the production of inositol phosphates in response to anti-CD3 monoclonal antibody (mAb) stimulation at a concentration that did not affect the binding of anti-CD3 mAb. Tyrosine phosphorylation induced by crosslinking of CD3 molecules was significantly inhibited by costunolide in a dose-dependent manner. These results suggest that costunolide inhibits the killing activity of CTL through preventing the increase in tyrosine phosphorylation in response to the crosslinking of T-cell receptors.

4-Butyrolactone↗

PubMed1995

Paraparesis after rib penetration of the spinal canal in neurofibromatous scoliosis.

Paraplegia or paraparesis is uncommon in patients with neurofibromatous scoliosis. The main causes of spinal cord compression in neurofibromatosis are vertebral angulation, vertebral subluxation, and tumorous lesions around the spinal cord. We report a rare case of paraparesis due to spinal cord compression by a rib penetrating the spinal canal in a patient with neurofibromatous scoliosis. There was complete recovery after laminectomy and proximal resection of the compressing rib along with combined anterior and posterior spinal fusion.

Child↗

PubMed1994

Bone dysplasia in a child born to parents with osteogenesis imperfecta and pseudoachondroplasia.

We report on a boy born to a mother with pseudoachondroplasia and a father with osteogenesis imperfecta (Sillence type III). At birth, the boy was found to have osteogenesis imperfecta type III. Although clinical findings of pseudoachondroplasia were not manifested at the age of 8 months, roentgenographic findings showed characteristics of pseudoachondroplasia in addition to those of osteogenesis imperfecta. He died of respiratory distress at age 15 months.

Achondroplasia↗

PubMedDate not supplied

Antley-Bixler syndrome: a disorder characterized by congenital synostosis of the elbow joint and the cranial suture.

The Antley-Bixler syndrome is a rare disorder characterized by craniosynostosis, midface hypoplasia, radiohumeral synostosis, joint contractures, arachnodactyly, and femoral bowing and fractures. We report four cases with this disorder, all of which had craniosynostosis, midface hypoplasia with characteristic facial appearance, and contractures of bilateral elbow joints. However, femoral bowing, fractures, and arachnodactyly were not seen in our patients. In addition, proximal phalanges of the thumb and the great toe showed deformity of the delta phalanx in two cases. Characteristic features in these cases were the synostotic deformity of the elbow joint; three had radioulnahumeral synostosis, and one had radioulnar synostosis. Therefore, our cases indicated that various synostotic patterns of the elbow joints may exist in this syndrome. It is reasonable to propose that characteristic craniofacial appearance associated with the synostosis of the elbow joints of various forms should be considered minimal diagnostic criteria of the Antley-Bixler syndrome.

Child, Preschool↗