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Biomedical subjects

I Yoshida

Publications and source records attributed to I Yoshida.

At least 199 records · Page 11Linked to original sources
PubMed1992

Identification of a cell membrane receptor for interferon induction by poly rI:rC.

PR-RK, a cell line derived from rabbit kidney cells (RK-13), was insensitive to the cytotoxic effect and interferon (IFN) inducing activity of the copolymer of riboinosinic and ribocytidylic acid (poly rI:rC). However, PR-RK was sensitive to the cytotoxic effect of the copolymer of riboadenylic and ribouridylic acid (poly rA:rU). Comparison of PR-RK cells and RK-13 cells by cytofluorometric analysis revealed that the binding of poly rI:rC was considerably reduced on PR-RK cells. These results suggested that the receptor for poly rI:rC might be different from the receptor for poly rA:rU, and this difference could provide a basis for the identification of the dsRNA receptor on cell surface. Western blot analysis of the components of cell membrane fraction prepared from RK-13 cells was performed by using a monoclonal antibody, which binds to cell membrane of RK-13 cells but not to PR-RK cells, and which blocks IFN induction by poly rI:rC in RK-13 cells. The 60K protein was identified as one of the poly rI:rC receptor protein.

Animals↗
PubMed1992

[Malignant fibrous histiocytoma of the mediastinum associated with bilateral adrenal gland metastases--a case report].

A 55-year-old female underwent complete resection of left posterior mediastinal tumor and both adrenal gland tumors. Histological examination revealed malignant fibrous histiocytoma (MFH) showing a storiform pattern. Her postoperative course was uneventful and well one year after the operation. We concluded the tumor arose from the mediastinum and metastasized to the bilateral adrenal glands. No other case was reported that primary MFH of the mediastinum with distant metastases was completely resected including metastatic lesions.

Adrenal Gland Neoplasms↗
PubMed1992

[Mitral valve replacement in a patient with hereditary hemorrhagic telangiectasia].

A 46-year-old female with mitral insufficiency complicated by hereditary hemorrhagic telangiectasia (Osler's disease) underwent successfully mitral valve replacement. The patient had a history of repeated large-volume nasal bleeding. Mitral valve replacement using a xenograft was safely performed with various attempts for preventing abnormal postoperative hemorrhage.

Bioprosthesis↗
PubMed1992

[Surgical treatments of emphysematous giant bullae accompanied with severe bronchial asthma].

Two operative cases of emphysematous giant bullae of the lung accompanied with bronchial asthma were reported. Case 1: A 41-year-old man suffering from dyspnea and fever-up was diagnosed as emphysematous giant bullae of the right lung accompanied with severe bronchial asthma. Preoperative examination revealed severe hypoxemia (PO2 46 mmHg) and mixed type ventilatory disorder; VC 1.68 t (41%), FEV1.0 0.59 l (35%). On the first anesthesia, operation was postponed by the severe asthmatic attack and circulatory collapse. After the complete prevention of the attack by giving corticosteroid (25 mg/day) for two weeks, resection of giant bullae could be performed safely. Case 2: A 31-year-old man complaining wheeze was diagnosed as emphysematous giant bullae of bilateral upper lobes of lung accompanied with bronchial asthma. Preoperative and intraoperative states were uneventful, though, on the day after the operation, asthmatic attack occurred due to the difficulty in expectation of sputa. It took 12 hours and many kinds of drugs to improve the respiratory state. In the patients of bronchial asthma, preoperative sufficient suppression of hyperreactivity of airway tracts and postoperative careful treatment to avoid asthmatic attack seem to be indispensable.

Adult↗
PubMed1992

[Effects of dobutamine and isoproterenol on systemic hemodynamics and myocardial metabolism in children after open heart surgery].

The purpose of this study is to know the effects of Dobutamine (DOB) and Isoproterenol (ISP) on the systemic hemodynamics and myocardial metabolism in the acute phase after open heart surgery in children. Twelve patients with congenital heart disease were administered 5 and 10 micrograms/kg/min (gamma) of DOB, then 0.005 and 0.01 gamma of ISP, and the systemic hemodynamic and metabolic data were taken before and after the administration of the drugs. DOB: DOB increased HR and SVI, so CI rose up markedly. The systolic, diastolic and mean blood pressure also rose up after both doses. CVP and PCWP were depressed at both dosage levels. SVRI and PVRI did not show an appreciable change. ISP: ISP increased HR, CI and systolic blood pressures significantly. On the other hand, SVRI, PVRI and PCWP were decreased at both dosage levels. Myocardial metabolism: The two drugs tested did not exhibit any effect on the progress of anaerobic myocardial metabolism. The myocardial oxygen uptake rate was decreased with DOB and ISP. These phenomena probably suggest that DOB and ISP dilate the coronary vascular bed. From the above data, the following effects can be expected by the use of each drug after open heart surgery in children; 1) powerful inotropic and chronotropic action by DOB, and 2) chronotropic action and after-load reduction by ISP.

Anaerobiosis↗
PubMed1992

[Experience in the treatment of acute fulminating myasthenia gravis].

During past 15 years, 188 myasthenia gravis (MG) patients underwent thymomectomy or thymectomy with extended resection of the adipose tissue around the thymus in our institution. Four of 188 patients (2%) had to be given respiratory support within 2 months after the onset of MG. We defined this MG as the acute fulminating type. There were 2 male and 2 female patients, ranging in age from 22 to 44 years (average, 32.5 years). Three of these patients had thymoma. One of these patients was post-thymomectomy myasthenia gravis and another patient was d-penicillamine induced myasthenia gravis. Two patients admitted on respirator for respiratory crisis. All patients underwent operation within 2 weeks after admission. The duration of respiratory support ranged from 10 to 120 days (mean 44) after operation. The period of the hospital stay ranged from 8 months to 2 years 1 month (mean 1 year 5 months). During acute stage after operation, the patients needed ACTH, steroid, immunosuppressants (azathioprine, Bredinin) and plasma pheresis depending on their severity of myasthenic symptoms. In 2 patients dose of steroid could be reduced without deterioration of the symptoms. They are doing well with small dose of steroid. In one patient plasma pheresis was performed 6 years after thymectomy. Various symptoms due to myasthenia gravis and rheumatoid arthritis has recurred 10 years after thymectomy. The titer of acetylcholine receptor antibody of this patient has been continuing in high level.

Acute Disease↗
PubMed1992

[Bicuspid aortic valve with sudden onset of aortic insufficiency due to rare causes: report of two cases].

This report describes two cases of aortic valve replacement which was warranted by the suddenly developed aortic regurgitation due to a congenitally bicuspid aortic valve. Aortic insufficiency was caused by the rupture of the strand which lifted a larger cusp to the aortic wall in one, and by the perforation of valvular aneurysm in another. Reviewing the literature these types of aortic insufficiency are rarely reported.

Acute Disease↗
PubMed1992

[Surgical treatment of myasthenia gravis associated with Graves's disease].

During past 30 years, we experienced 253 patients who underwent surgery for myasthenia gravis. Among these patients, 9 were associated with Graves' disease. No patients had thymoma. Five patients underwent thymectomy after they had become euthyroid by medical treatment, though four patients required subtotal thyroidectomy before thymectomy. One patient developed myasthenic crisis following thyroidectomy and was treated with respirator for 5 days. But thymectomy was performed without myasthenic crisis in these four patients between 25 days and 60 days after thyroidectomy. They have been doing well and no see-saw phenomenon was presented. Thymectomy is safe and effective even in the patients with Graves's disease, and we recommend to perform it after they become euthyroid by medical or surgical treatment.

Adult↗
PubMed1991

Changes of fluorescence lifetime and rotational correlation time of bovine serum albumin labeled with 1-dimethylaminonaphthalene-5-sulfonyl chloride in guanidine and thermal denaturations.

The nanosecond fluorescence depolarization method was applied to measure the fluorescence lifetime (tau) and the rotational correlation time (phi) of bovine serum albumin (BSA) labeled with 1-dimethylaminonaphthalene-5-sulfonyl chloride (dansyl-Cl). Changes of tau and phi of dansyl BSA in the guanidine denaturation and in the thermal denaturation were examined. In parallel, the secondary structural change of dansyl BSA was followed by circular dichroism measurements. The magnitude of tau was almost unchanged between 1 and 2M guanidine, where the secondary structure of the protein was predominantly disrupted; whereas that of phi began to increase before the disruption of secondary structure in the guanidine denaturation. In the thermal denaturation, in contrast, changes of both tau and phi occurred in a temperature range where the secondary structure was predominantly disrupted. The volume of equivalent sphere (Ve) and the axial ratio (rho) for the BSA were 3.6-3.8 x 10(-19) cm3 and 3.6 at 2 M guanidine as against 2.1 x 10(-19) cm3 and 2.2 in the absence of guanidine (25 degrees C), respectively. The magnitudes of Ve and rho were 4.9 x 10(-19) cm3 and 4.5 at 65 degrees C, respectively. Although the secondary structural change of dansyl BSA was irreversible in the thermal denaturation, Ve and rho were reversible.

Dansyl Compounds↗
PubMed1991

The natural history and timing of the radical operation for subpulmonic ventricular septal defects.

In order to further understand the natural history and timing of repair for subpulmonic (type I) ventricular septal defect (VSD), 70 patients who underwent radical surgery were reviewed. The patients with this type of VSD accounted for 30 per cent of a total 236 children with types I, II and III VSD who underwent repair between 1978 and 1989. The frequency of aortic regurgitation was 30 per cent, being higher in the group aged older than 10 years than in the younger group (p less than 0.05). The median ages of patients with normal, prolapsed and regurgitated valves were 5, 6.5, and 10 years, respectively, and each value exhibited significant differences (p less than 0.05). The left to right shunt ratio and systolic pulmonary artery pressure of the patients with normal valves were significantly higher than those of the patients with abnormal valves. The outcome of the patients with regurgitation varied according to Sellers grading with cases of grade two valvular deformities recovering well after the repair, while cases of grade three had deformities of grade one or two severity remaining. These results led us to establish the following strategy for patients with I-VSD: 1) a child should be regularly checked by USG; 2) a child noted as having a prolapsing valve is recommended to undergo repair by the age of 10 to 12 years; and 3) a child found to have regurgitation should undergo repair as soon as possible, unless the valve regurgitation does not become more severe than Sellers grade two.

Adolescent↗
PubMed1991

Development of immunogenic recombinant Oka varicella vaccine expressing hepatitis B virus surface antigen.

Recombinant Oka varicella vaccine expressing hepatitis B virus (HBV) surface antigen (HBs) was constructed by inserting the HBs gene into the viral thymidine kinase (TK) gene and was examined for its immunogenicity in guinea-pigs. The HBs gene encoding 25 amino acids of preS2 and the whole of the S region was inserted into the TK gene of the cloned plasmid. The chimeric plasmid DNA and Oka varicella vaccine DNA were cotransfected and recombinant virus was isolated after immunofluorescence screening using a monoclonal antibody to HBs and a fluorescein-conjugated anti-mouse antibody. Expression of viral HBs was detected in the cytoplasm of infected cells and was stable over several repeated passages in vitro. The recombinant virus expressed 26K and 30K HBs molecules in infected cells and the culture supernatant contained 30K and 35K HBs molecules. HBs was purified at a density of 1.20 g/ml from the culture supernatants. The recombinant virus induced an antibody response to HBs as well as to varicella-zoster virus (VZV) in guinea-pigs, and the antibody titre to HBs was comparable to that induced by a recombinant HBs subunit vaccine produced in yeast. Thus a single dose of live recombinant Oka varicella vaccine could induce good immunity to VZV and HBs. The recombinant Oka varicella vaccine expressing HBs may be a good candidate for a combined HBV and VZV vaccine.

Animals↗
PubMed1991

Antiviral activity of oxetanocins against varicella-zoster virus.

Several new nucleosides with an oxetanosyl-N-glycoside group, named oxetanocins, were evaluated for their antiviral activities against varicella-zoster virus (VZV) in human embryo lung cells. 9-(2-deoxy-2-hydroxy-methyl-beta-D-erythro-oxetanosyl)guanine (OXT-G) and 9-(2-deoxy-2-hydroxymethyl-beta-D-erythro-oxetanosyl)-2- aminoadenine were effective against not only thymidine kinase-positive (TK+) VZV (YS strain) but also thymidine kinase-negative (TK-) VZV (YSR strain), whereas carbocyclic OXT-G was effective against TK+ VZV but not against TK- VZV. [3H]OXT-G was incorporated into TK+ VZV-infected cells and TK- VZV-infected cells more than into mock-infected cells and was converted into the triphosphate form.

Adenine↗
PubMed1991

Structure and organization of the hepatitis C virus genome isolated from human carriers.

Hepatitis C virus (HCV) is a major causative agent of posttransfusion non-A, non-B hepatitis, which often develops into malignant chronic diseases, including liver cirrhosis and hepatocellular carcinoma. We have cloned from human carriers overlapping cDNAs (9,416 bp) covering the entire coding region of the HCV genome. The latter encodes a 3,010-amino-acid polyprotein. In addition, there are 332 and 54 bases of 5' and 3' noncoding sequences, respectively. Our HCV strain has a 77% nucleic acid identity to the HCV strain cloned by workers at Chiron Corporation. The hydrophobicity profile of the putative polyprotein is similar to those of flaviviruses, but it has limited amino acid homology to polyproteins of flaviviruses and other viruses, indicating that HCV is at most distantly related to flaviviruses.

Amino Acid Sequence↗
PubMed1991

Metabolism of 1-13C-propionate in vivo in patients with disorders of propionate metabolism.

Metabolism of propionate in human subjects was studied using bolus administration of 1-13C-propionate i.v. or orally. The study population consisted of five patients with propionic acidemia (PA), eight with methylmalonic acidemia (MMA; four responsive to vitamin B12), one each with multiple carboxylase deficiency and transcobalamin-II deficiency, and five healthy volunteers. Concentrations of 1-13C-propionate were measured in blood in three patients with PA, two with MMA, and two controls. Breath samples were obtained at intervals during 3 h after the dose, isotopic enrichment of 13CO2 was measured, and the cumulative percentage of recovery of 13C was calculated from the individual's predicted resting energy expenditure. Recovery of 13CO2 and half-time of 1-13C-propionate in PA were significantly less than normal. The same parameters in MMA were below normal, but significantly greater than in PA. Recovery of 13CO2 was well correlated with clinical severity in PA, but did not correlate in MMA. Differences between MMA and PA may indicate different distribution of propionate pools, differences in inducibility of residual enzyme activities, or an alternate pathway for decarboxylation of propionate available in MMA but not PA. Only one patient with PA demonstrated increased 13CO2 production during biotin treatment. In a B12-responsive MMA patient, no differences were noted within 2 d of initiating treatment with B12, but there was an increase in 13CO2 production after 4 mo. Recovery of 13CO2 was normal in the patient with transcobalamin-II deficiency before and after treatment with vitamin B12.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Expression of the hepatitis B surface antigen gene containing the preS2 region in Saccharomyces cerevisiae.

We constructed a plasmid, pBH103-ME5, in which the region encoding the 10 preS2 amino acid residues and the S domain of the hepatitis B surface antigen (HBsAg) were regulated by the promoter of the yeast repressible acid phosphatase gene. Saccharomyces cerevisiae carrying pBH103-ME5 produced the HBs antigen (yHBsAg), when it was cultured in a medium containing a low concentration of phosphate. The antigen was purified to homogeneity. Its molecular weight was determined by Western blotting to be 24,000, and its amino acid composition agreed well with that deduced from the nucleotide sequence. The C-terminal amino acid sequence of yHBsAg was exactly the same as that predicted from the nucleotide sequence, while the N-terminal amino acid acetylserine, which was followed by 8 amino acid residues coded by the preS2 region. These results indicate that the recombinant yeast produced a single polypeptide consisting of the preS2 region and the subsequent S domain after being processed at the N-terminus.

Amino Acid Sequence↗
PubMed1991

Effect of serum treatment on pertussis antibody determination by ELISA.

Determination of anti-PT and anti-FHA antibodies by ELISA and neutralization titer by CHO-cell method were performed with inactivated and uninactivated human sera. The findings were as follows: in inactivated sera, higher anti-PT ELISA antibody titers were shown compared with the titers determined with corresponding inactivated sera, especially in sera having low ELISA antibody titers; however, anti-FHA ELISA antibody titers remained identical, with the uninactivated or inactivated sera. CHO-cell neutralization titer remained identical and stable between the uninactivated and inactivated sea. CHO-cell neutralization titers correlated with anti-PT ELISA antibody titers in sera without inactivation. Anti-PT ELISA antibody titers in inactivated sera, however, did not correlate with the corresponding CHO-cell neutralization titers. These results suggest the possible existence of (a) substance(s) with affinity to PT which enhance(s) the ELISA reaction when sera are inactivated. Therefore, the inactivation of sera is not favorable for anti-PT determination by ELISA.

Adhesins, Bacterial↗