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Biomedical subjects

S Arai

Publications and source records attributed to S Arai.

At least 253 records · Page 14Linked to original sources

Large-scale production and purification of an Erwinia ananas ice nucleation protein and evaluation of its ice nucleation activity.

The ice nucleation-active protein of Erwinia ananas IN-10 (inaA protein) was over-expressed as inclusion bodies in Escherichia coli in a yield of 15.3 mg of inaA protein from 60 mg of bacterial cells on a dry-matter basis. The inaA protein was purified from the inclusion bodies by solubilization with detergents to obtain a protein preparation free from sugar and lipid. This preparation had a distinct ice nucleation activity, indicating that the inaA protein per se is able to act as a nucleus.

Amino Acid Sequence↗

Early detection of acute allograft rejection in rat heart transplantation: flowcytometric monitoring of interleukin 2 receptor expression on CD8 positive lymphocytes.

To assess the usefulness of flowcytometric monitoring in the early detection of acute allograft rejection, we studied surface markers of graft infiltrating lymphocytes, coronary sinus blood lymphocytes and peripheral blood lymphocytes after rat heart transplantation. Fisher rats served as donors and Lewis rats as recipients. Among recipients that received no immunosuppression, grafts were removed 2 days after transplantation (Ongoing Rejection Group: n = 7) and on the day of terminal rejection (Rejection Group: n = 7). The Immunosuppression Group (n = 7) was treated with cyclosporine A at a dose of 3 mg/kg/day intramuscularly for 14 days. The following two color analyses were studied: OX8 (anti-CD8) with OX39 (anti-interleukin 2 receptor; IL2R), W3/25 (anti-CD4) with OX39, W3/25 with OX8. Histological grading demonstrated no significant difference between the Ongoing Rejection Group and the Immunosuppression Group, which showed mild rejection (1.29 +/- 0.27 versus 1.14 +/- 0.24). The proportion of CD8(+)IL2R(+) graft infiltrating lymphocytes showed a more significant increase in the Ongoing Rejection Group than in the Immunosuppression Group (32.1 +/- 3.05 versus 20.6 +/- 9.02; p < 0.01). The proportion of CD8(+) IL2R(+) coronary sinus blood lymphocytes also showed significant increase in the Ongoing Rejection Group compared with the Immunosuppression Group (4.63 +/- 1.91 versus 2.52 +/- 1.60; p < 0.05). These results suggest that this technique can detect acute allograft rejection earlier than endomyocardial biopsy, before the phase in which histological findings become evident.

Acute Disease↗

[A case of congenital atrial flutter associated with atrial septal defect].

We report the case of a 8-month-old boy with atrial septal defect associated with congenital atrial flutter. He was operated on for ASD successfully. Atrial flutter in infants has been reported to be uncommon and to have a poor prognosis when associated with underlying cardiac disease. Therefore, early surgical intervention may improve the prognosis.

Atrial Flutter↗

[A case of sho-saiko-to-induced pneumonitis, diagnosed by lymphocyte stimulation test using bronchoalveolar lavage fluid].

A 66-year-old Japanese man was admitted to our hospital with fever, cough and dyspnea. He had been taking Sho-Saiko-to, a traditional Chinese medicine, for twenty days. On admission, chest X-ray examination revealed a reticular pattern in the bilateral lungs, and respiratory failure was evident. Serum levels of CRP and LDH were elevated. A differential cell count of the bronchoalveolar lavage fluid (BALF) showed that lymphocytes and eosinophils were increased. Alveolitis with lymphocyte and plasma cell infiltration was observed in a pathological specimen obtained by transbronchial lung biopsy. After all drugs had been discontinued, PaO2, serum CRP and serum LDH improved, and the reticular pattern in the bilateral lungs gradually resolved without administration of corticosteroids or antibiotics. A lymphocyte stimulation test for Sho-Saiko-to using BALF gave a positive result, although LST using blood gave a doubtful reaction. The diagnosis of Sho-Saiko-to-induced pneumonitis was made from the clinical course, laboratory findings, BALF cell analysis, pathological findings and LST using BALF. Only 13 cases of pneumonitis due to administration of traditional Chinese medical drugs have been reported. This case suggests that LST using BALF is useful for the diagnosis of drug-induced pneumonitis.

Aged↗

[Perioperative insertion of peritoneal dialysis catheter].

Silicon rubber peritoneal dialysis catheter (Tenkoff) was inserted perioperatively in neonates undergoing cardiac surgery and also in those patients in whom right-sided heart failure may occur. This method is easy and safe even in neonates. Post operative excessive fluid retention could be avoided using this method.

Acute Kidney Injury↗

Expression of oryzacystatin cDNA using yeast artificial chromosome under ADH promoter in baker's yeast.

We constructed an expression vector into a yeast artificial chromosome (YAC) harboring the cDNA for oryzacystatin, a cysteine proteinase inhibitor from rice, under the control of the yeast ADH promoter. When the expression vector was introduced into Saccharomyces cerevisiae in the form of either an artificial chromosome or a circular plasmid, transformants carrying the DNA grew well in a selective medium. However, the content of the introduced DNA decreased significantly during passages in non-selective YPD medium. The stability of the introduced DNA was enhanced in selected clones obtained as colonies viable in selective medium after many passages in YPD medium. The stable transformants thus obtained expressed the mRNA for oryzacystatin at levels as high as those of intrinsic yeast ADH.

Alcohol Dehydrogenase↗

Lithocholate binding by Y and Y' proteins in bovine small intestine.

Cytosolic proteins may play an important role in the intracellular transport of bile acids in enterocytes. The lithocholate binding properties of cytosolic protein from bovine small intestine were studied. Lithocholate binding was observed in the Y (45-50 kDa), Y' (30-35 kDa), and Z fractions (10-15 kDa) following gel filtration of cytosol. A Y protein with glutathione S-transferase activity (46 kDa) was purified by S-octyl-glutathione affinity chromatography and chromatofocusing (eluted at pH 7.5) of the Y fraction. Two Y' bile acid binding proteins with dihydrodiol dehydrogenase activity were partially purified from the Y' fraction by chromatofocusing and hydroxyapatite-HPLC. The lithocholate binding affinity of Y' protein (Kd < 0.35 microM) was higher than that of Y protein (Kd = 2 microM) and was comparable to that of Z protein (Kd = 0.2 microM). The binding affinity of Y protein was higher for bilirubin (Kd = 2.5 microM) than that for BSP (Kd = 200 microM). This was comparable to the binding affinity of bovine hepatic Y protein. These data indicate that Y' and Z proteins participate in the intracellular transport of bile acids from the brush border to the basolateral pole in enterocytes.

Animals↗

Corn kernel cysteine proteinase inhibitor as a novel cystatin superfamily member of plant origin. Molecular cloning and expression studies.

A full-length cDNA clone for a cysteine proteinase inhibitor (cystatin) was isolated from a lambda gt10 cDNA library of immature corn kernels by screening with a mixture of cDNA inserts for oryzacystatins I and II. The cDNA clone spans 960 base pairs, encoding a 135-amino-acid protein containing a signal peptide fragment. The protein, named corn cystatin I, is considered to be a member of the cystatin superfamily, since it contains the commonly conserved Gln-Val-Val-Ala-Gly region that exists in most known cystatins as a probable binding site and is significantly similar to other cystatins in its overall amino acid sequence. Corn cystatin I expressed in Escherichia coli showed a strong papain-inhibitory activity. Northern blot analysis showed that the amount of mRNA for corn cystatin I reaches a maximum 2 weeks after flowering and then decreases gradually.

Amino Acid Sequence↗

Dopamine receptor antagonists increase markedly the quantity of retrograde transport of HRP in the rat masseteric motoneuron.

Horseradish peroxidase (HRP) was injected, bilaterally, into the rat masseter muscle, subsequent to an intramuscular or intraperitoneal injection of one of five dopamine antagonists (chlorpromazine and haloperidol as the D1 and D2 receptor antagonist, SCH 23390 as the specific D1 receptor antagonist, sulpiride and domperidone as the specific D2 receptor antagonist). Control rats received an injection of a corresponding vehicle solution. After a survival period of 16 h, the brainstem was cut into 60 microns cryosections and processed with the TMB technique. The amount of retrogradely transported HRP was quantitatively measured in terms of the amount of HRP reaction product present in the motoneuron by the method which we have developed using an image processing system combined with a light microscope and a TV camera. Chlorpromazine, haloperidol, SCH 23390 and sulpiride significantly raised the quantity of retrograde transport of HRP. On the contrary, domperidone which can not penetrate the blood-brain barrier showed no significant change in the amount of the retrograde transport. In addition, an intravenous injection of chlorpromazine (8 mg/kg) was found to increase the amplitude of monosynaptic masseteric reflex EMG activity evoked by stimulations of the mesencephalic trigeminal nucleus. These results suggest that a possible regulatory system involving the dopamine receptor in the uptake and retrograde transport of HRP from axon terminals to cell bodies of the masseteric motoneuron exists in higher order neurons which make synaptic contact with the motoneuron.

Animals↗

Inhibitory effect of oryzacystatins and a truncation mutant on the replication of poliovirus in infected Vero cells.

Poliovirus, a picornavirus family member, requires the processing of its poly-protein by its own cysteine proteinase for replication. Oryzacystatin-I and oryzacystatin-II, proteinaceous cysteine proteinase inhibitors (cystatins) of rice seed origin, were found to inhibit the replication of poliovirus effectively in infected Vero cells in vitro. Truncated oryzacystatin-I, which lacks the NH2-terminal 25 amino acid residues of the intact protein, is an even more effective inhibitor, eliciting its effect at concentrations of less than 0.25 nmol/ml. The low molecular weight cysteine proteinase inhibitors, E-64, E-64C and loxistatin, showed no anti-viral effect at any concentration investigated.

Animals↗

Molecular cloning of curculin, a novel taste-modifying protein with a sweet taste.

cDNA clones for curculin, a novel taste-modifying protein, were isolated and sequenced. The encoded prepro-curculin was composed of 158 amino acid residues including a signal sequence of 22 residues and a carboxy-terminal extension peptide of 22 residues. Northern blot analysis showed that the mRNA for curculin was first detected in Curculigo latifolia fruits at 2 weeks after pollination and remained at a constant level for the following 4 weeks.

Amino Acid Sequence↗

Multivessel coronary revascularization with bilateral internal thoracic artery grafts.

Sixteen patients underwent coronary revascularization with bilateral internal thoracic artery (ITA) grafts between 1988 and 1989 at the Okayama University Hospital. A total 39 coronary grafts were performed, being an average of 2.4 grafts per patient. Each patient received bilateral ITA grafts, and in 5 patients an additional 7 grafts were constructed with 5 autologous veins and 2 gastroepiploic arteries. The right ITA was grafted as a free graft in 4 patients. The ITA graft patency rate was 96.8 per cent (31/32) at the time of hospital discharge. The postoperative morbidity included one reoperation for bleeding and one myocardial infarction. Coronary artery bypass grafting with bilateral ITA grafts can be safely performed and its application facilitates complete revascularization with arterial grafts.

Aged↗

Binding of bile acids, organic anions, and fatty acids by bovine intestinal Z protein.

Z protein from bovine small intestinal mucosa was purified and its binding affinities for bile acids, organic anions, and fatty acids were compared with those of bovine hepatic Z protein. Purification of Z protein from intestinal and hepatic cytosol was performed by gel filtration, chromatofocusing, and hydroxyapatite chromatography. Both purified proteins had the same molecular weight (Mr 14,000) and eluted from a chromatofocused gel at about pH 10. Binding studies were performed by the competitive displacement of 8-anilinonaphthalene-1-sulfonic acid and by equilibrium dialysis. Binding affinities for bile acids, organic anions, and fatty acids were very similar between intestinal and hepatic Z proteins. Although the real physiologic role of Z protein remains to be further elucidated, these data indicate that intestinal Z protein participates in the mechanism of intracellular bile acid transfer in enterocytes.

Animals↗

Lymph node interdigitating cell sarcoma. A case report.

A 54-year-old man was admitted because of right supraclavicular lymphadenopathy of some weeks duration. Computed axial tomography revealed a large multinodular lesion in a supraclavicular lymph node. The patient then had a supraclavicular lymph node biopsy. Light microscopy showed a tumor whose structure was suggestive of an interdigitating cell sarcoma. Enzyme and immunohistochemical analysis showed that the tumor cells possessed membranous adenosine triphosphatase activity, intracytoplasmic S100 protein, surface CD1a and CD4 antigens, and HLA-DR antigen. Ultrastructural examination showed that the cells exhibited many interdigitating cytoplasmic extensions, but no Birbeck granules. DNA content analysis of the tumor cells proved that the cells were malignant. These data are consistent with derivation from a lymph node interdigitating cell.

Biomarkers↗

The comparison of sun protection factor values with different light sources.

Sun protection factors (SPFs) were evaluated with three light sources (sunlight, a xenon arc solar simulator, and fluorescent lamps) in indoor and outdoor studies. Two types of light, UV-A+B and UV+Visible, were obtained from the solar simulator. The untanned backs of twenty-four healthy male volunteers were used as test sites. A broad spectrum sunscreen containing SPF 6, according to the manufacturer, was used. The sunscreen tested was applied at 2 mg/cm2. The actual SPF values were 4.8 with sunlight, 6.0 with UV-A+B, 4.9 with UV+Visible, and 11.8 with fluorescent lamps. There were no significant differences between the SPF values with sunlight and those with the solar simulator; the SPF value for fluorescent lamps was significantly higher. The SPF with UV-A+B of the solar simulator was similar to that with sunlight; the use of this light served to reduce pain on tested subjects. Therefore, UV-A+B from the solar simulator seems to be the most appropriate artificial light source for evaluating sunscreens.

Adult↗

Antimycoplasmal activities of new quinolones, tetracyclines, and macrolides against Mycoplasma pneumoniae.

Fifty strains of Mycoplasma pneumoniae were tested for susceptibility to new quinolones, tetracyclines, and macrolides. Temafloxacin, ofloxacin, and ciprofloxacin possessed the most mycoplasmacidal activity against these organisms. The MBC for 50% of the strains (MBC50)-to-MIC50 ratio for each of these drugs was 4. The MBC50-to-MIC50 ratios for the tetracyclines and macrolides were markedly higher, within a range of 32 to 2,000. On the basis of these results, temafloxacin and ofloxacin might be promising antimicrobial agents for the treatment of mycoplasmal infection.

4-Quinolones↗

[In vitro antimicrobial activities of new quinolone antibiotics against Mycoplasma pneumoniae].

The antimicrobial activities against Mycoplasma pneumoniae of new quinolones (temafloxacin, ofloxacin, ciprofloxacin, enoxacin, and norfloxacin) and of tetracyclines and macrolides as controls were compared. Among new quinolones, temafloxacin, ofloxacin, and ciprofloxacin were more active than enoxacin and norfloxacin against fifty strains of Mycoplasma pneumoniae, giving MIC50 and MIC90 significantly lower than those of the latter two, by the agar-dilution method. The three more active antibiotics in the above assay were then determined for MICs and MBCs by the broth-dilution method. The MICs of every antibiotic except erythromycin determined by both the methods were very similar each other. The MICs of erythromycin determined by the broth-dilution method were ten-times higher than those determined by the agar-dilution method. Temafloxacin and ofloxacin gave MBCs only about four-times higher than MICs, whereas ciprofloxacin, minocycline, erythromycin and josamycin gave MBCs as much as 15 to 1,000-times higher than MICs. From the MICs and MBCs determined by the two assay methods, it is apparent that temafloxacin and ofloxacin, and to a less extent ciprofloxacin, have more potent mycoplasmacidal activities than do macrolides and tetracyclines.

Anti-Bacterial Agents↗