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Biomedical subjects

T Miyazawa

Publications and source records attributed to T Miyazawa.

At least 163 records · Page 9Linked to original sources
PubMed1998

Airway stenting in Japan.

Various types of outstanding airway stents have been made commercially available. In Japan, a total of 1004 airway stents (Dumon stents (Novatech, Aubagne, France), Gianturco Z stents (Cook Ins, Bloomington, USA), Ultraflex stents (Boston Scientific Corp, Natick, MA, USA), and Dynamic Y stents (Ruesch AG, Kernen, Germany)) were implanted from July 1991 until February 1998. Of all the various stents, the Dumon stent has become the standard worldwide. Also, the Dumon stent has been replacing the Gianturco Z stent as the preferred stent throughout Japan. The Dumon stent was the first stent covered by Japanese National Health Insurance. Therefore, we present our 5-year experience with the Dumon stent at our institution. In our experience, stenting is effective for the immediate and lasting relief of symptoms in patients with severe malignant obstruction of major airways.

Airway Obstruction↗
PubMed1998

Apoptosis in feline panleukopenia virus-infected lymphocytes.

Feline panleukopenia virus (FPLV) was shown to induce apoptosis to feline lymphoid cells and to reduce the expression of interleukin-2 receptor alpha on the cells. FPLV-induced apoptosis might be a key element in the pathophysiology of atrophy of lymphoid tissues associated with feline panleukopenia caused by FPLV.

Animals↗
PubMed1998

DNA vaccination affords significant protection against feline immunodeficiency virus infection without inducing detectable antiviral antibodies.

To test the potential of a multigene DNA vaccine against lentivirus infection, we generated a defective mutant provirus of feline immunodeficiency virus (FIV) with an in-frame deletion in pol (FIVDeltaRT). In a first experiment, FIVDeltaRT DNA was administered intramuscularly to 10 animals, half of which also received feline gamma interferon (IFN-gamma) DNA. The DNA was administered in four 100-microg doses at 0, 10, and 23 weeks. Immunization with FIVDeltaRT elicited cytotoxic T-cell (CTL) responses to FIV Gag and Env in the absence of a serological response. After challenge with homologous virus at week 26, all 10 of the control animals became seropositive and viremic but 4 of the 10 vaccinates remained seronegative and virus free. Furthermore, quantitative virus isolation and quantitative PCR analysis of viral DNA in peripheral blood mononuclear cells revealed significantly lower virus loads in the FIVDeltaRT vaccinates than in the controls. Immunization with FIVDeltaRT in conjunction with IFN-gamma gave the highest proportion of protected cats, with only two of five vaccinates showing evidence of infection following challenge. In a second experiment involving two groups (FIVDeltaRT plus IFN-gamma and IFN-gamma alone), the immunization schedule was reduced to 0, 4, and 8 weeks. Once again, CTL responses were seen prior to challenge in the absence of detectable antibodies. Two of five cats receiving the proviral DNA vaccine were protected against infection, with an overall reduction in virus load compared to the five infected controls. These findings demonstrate that DNA vaccination can elicit protection against lentivirus infection in the absence of a serological response and suggest the need to reconsider efficacy criteria for lentivirus vaccines.

Amino Acid Sequence↗
PubMed1998

Nonepisodic angioedema associated with eosinophilia: report of 4 cases and review of 33 young female patients reported in Japan.

BACKGROUND: In 1984, Gleich et al. described 4 patients with episodic angioedema associated with eosinophilia (EAE), which was characterized by recurrent episodes of angioedema and urticaria, eosinophilia, elevated serum IgM, fever, increased body weight and a benign course without involvement of the internal organs demonstrating that it was a clinical entity distinct from the hypereosinophilic syndrome. Thereafter, 37 cases of EAE have been reported in Japan, 33 cases of which, although similar, had a different evolution from classical EAE. OBJECTIVE: To describe 4 cases and review the cases of angioedema associated with eosinophilia reported in Japan. RESULTS: Four Japanese female patients had persistent angioedema mainly involving the hands and lower legs, and eosinophilia which resolved within a few months. The review of the 37 cases of EAE in the Japanese literature demonstrated that in 33 cases, there were common characteristics which differed from EAE. These included: (1) the absence of recurrent attacks; (2) the predominance of young females (20-37 years, with a mean of 26 years); (3) the localization of the angioedema to the extremities; (4) the absence of increase in the serum IgM level, and (5) the effectiveness of low-dose prednisone or even the occurrence of spontaneous remission. CONCLUSION: We propose that persistent angioedema with eosinophilia can be classified into 2 types, i.e. one being an episodic (recurrent) type as reported by Gleich and a nonepisodic type as our 4 cases and others found in the Japanese literature.

Adult↗
PubMed1998

Development of a method for the quantitation of benzphetamine metabolites in human urine by high-performance liquid chromatography.

We developed a high-performance liquid chromatography (HPLC) method for quantitating p-hydroxy-N-benzylamphetamine glucuronide (pHBAG) and p-hydroxy-benzphetamine glucuronide (pHBZG), which are urinary metabolites of benzphetamine, in humans. Urine samples were hydrolysed with beta-glucuronidase (EC 3.2.1.31) at 37 degrees C overnight and the treated urine was applied to a solid phase extraction column. After washing the column with water, 0.01 mol/L acetic acid and methanol, pHBA and pHBZ were eluted with dichloromethane:isopropanol:28% ammonium hydroxide (78.4:19.6:2.0 v/v). The eluate was evaporated and the residue was dissolved in acetonitrile: 5 mmol/L 1-pentane sulphonic acid (5:95 v/v) and analysed by HPLC with gradient elution. The amounts of urinary pHBAG and pHBZG excreted by two human subjects after oral administration of 10 mg benzphetamine hydrochloride were determined. About 10-15% of benzphetamine was found to be excreted as pHBAG and pHBZG, and almost all of these metabolites were excreted within 24 h. Urine samples should be collected as early as possible after ingestion of benzphetamine to detect pHBAG and pHBZG.

Administration, Oral↗
PubMed1998

Simultaneous analysis of benzphetamine and its metabolites, and quantitation of urinary p-hydroxy-N-benzylamphetamine by micellar electrokinetic chromatography.

We developed a method for simultaneous analysis of benzphetamine (BZ) and its metabolites, p-hydroxy-N-benzylamphetamine (pHBA), p-hydroxybenzphetamine (pHBZ), amphetamine (AP), methamphetamine and p-hydroxymethamphetamine by micellar electrokinetic chromatography (MEKC). Urine samples from 0-15 h (3-h intervals) after oral administration of BZ (10 mg) were hydrolyzed with beta-glucuronidase (EC 3.2.1.31) at 37 degrees C overnight. The treated urine was applied to a solid phase extraction column Bond Elut Certify. After sequentially washing the column with water, 0.1 mol/l acetic acid and methanol, the samples were eluted with dichloromethane:isopropanol:28% ammonium hydroxide=78.4:19.6:2.0 (v/v %). The eluate was evaporated and the residue dissolved in running buffer was analyzed by MEKC. In urine from 0-3 h, AP, pHBZ and pHBA were detected. After that, only pHBA, which is one of the major metabolites of BZ in human urine, could be detected in the urine by the present method. A method for quantitation of pHBA by MEKC is described here. The effects of acetonitrile and sodium dodecyl sulfate in the running buffer of MEKC on the separation of BZ and its metabolites are also reported.

Acetonitriles↗
PubMed1998

Structure-related emission spectrometric analysis of the chemiluminescence of catechins, theaflavins and anthocyanins.

This study for the first time achieved an emission spectrometric analysis of the chemiluminescence of flavonoids in the presence of hydrogen peroxide, acetaldehyde and horseradish peroxidase, and revealed that the maximum emission wavelengths (Emax) strictly differ among catechins (E-max 630 nm), theaflavins (Emax 690 nm) and anthocyanins (Emax 675 nm) according to their chemical structures. This technique enabled the direct incorporation of dietary tea catechin into rat intestinal mucosal cells to be spectrometrically confirmed.

Acetaldehyde↗
PubMed1998

Identification of deoxy-D-fructosyl phosphatidylethanolamine as a non-enzymic glycation product of phosphatidylethanolamine and its occurrence in human blood plasma and red blood cells.

The amino-carbonyl reaction (Maillard reaction), also known as glycation, of egg-yolk phosphatidylethanolamine (PE) was induced by incubating PE (50 mg/ml) with D-glucose (222 mM) in a methanol medium containing 2,6-ditert-butyl-p-cresol as an antioxidant at 37 degrees C for 4 days. The resultant product, glycated PE (gPE), was then isolated from the reaction mixture by two-step normal and reversed-phase high-performance liquid chromatography with UV diode array detection and was characterized as having a 1:1:1 elemental ratio of phosphorus:nitrogen:sugar. The Fourier transform-nuclear magnetic resonance spectrum and infrared absorbance spectrum indicate the isolated gPE to have been deoxy-D-fructosyl PE, which is an Amadori product of PE. The fast atom bombardmentmass spectrometric data for the glycation product of authentic dioleoyl PE (1,2-di-9-octadecenoyl-sn-glycero-3-phosphoethanolamine) show that the molecular weight of gPE corresponds to that of glucose-conjugated PE in the form of an Amadori product. This Amadori product formation was also confirmed in PE/phosphate buffer dispersions and in phosphatidylcholine-PE liposome/phosphate buffer suspensions in the presence of D-glucose at 37 degrees C. gPE was degraded by phospholipase A2, C and D. Freshly spiked blood plasma and red blood cells (RBC) from nomal human volunteers contained substantial levels of gPE, the concentration corresponding to at least 9 mol% of PE. Remarkable formation of gPE, up to 15-45 mol% of PE in human blood plasma and RBC, was further confirmed by prolonged incubation with 5-45 mM D-glucose. The gPE formation in RBC was found to be proportional to the glycated hemoglobin formation.

Aging↗
PubMed1998

Seroepidemiological survey of feline retrovirus infections in domestic and leopard cats in northern Vietnam in 1997.

The prevalence of infections with three feline retroviruses (feline immunodeficiency virus (FIV), feline leukemia virus (FeLV) and feline syncytial virus (FSV)) was examined in northern Vietnam in 1997. We collected a total of 77 blood samples from 69 domestic and 8 leopard cats, and examined the presence of anti-FIV and FSV antibodies and FeLV p27 antigen in the plasma samples by the indirect immunofluorescence and/or two commercial kits. None of the samples was positive for FIV and FeLV. The overall positive rate of FSV was 31% and the positive rates among the domestic and leopard cats were 29 and 50%, respectively. We isolated FSV from peripheral blood mononuclear cells of 6 domestic and one leopard cats.

Animals↗
PubMed1998

Nucleotide sequences of glycoprotein I and E genes of equine herpesvirus type 4.

The nucleotide sequences of the glycoprotein I (gI) and E (gE) genes of equine herpesvirus type 4 (EHV-4) strain TH20 were determined. The predicted region encoding the EHV-4 gI gene is 1,263 nucleotides, corresponding to a polypeptide of 420 amino acids in length. The predicted region encoding the EHV-4 gE gene is 1,647 nucleotides, corresponding to a polypeptide of 548 amino acids in length. The EHV-4 gI and gE genes show 74% and 85% identity at the amino acid level with those of equine herpesvirus type 1 (EHV-1), respectively. Furthermore, we have found an open reading frame homologous to the EHV-1 gene 75, which overlaps in part with the 3' end of EHV-4 gE gene. These sequence data will be useful for development of a modified live vaccine against equine herpesvirus type 1 and 4 infections.

Amino Acid Sequence↗
PubMed1998

Eight-year observation and comparative study of specific pathogen-free cats experimentally infected with feline immunodeficiency virus (FIV) subtypes A and B: terminal acquired immunodeficiency syndrome in a cat infected with FIV petaluma strain.

Three specific pathogen-free cats experimentally infected with feline immunodeficiency virus (FIV) strains Petaluma, TM1 and TM2, respectively were observed for over 8 years. Without showing any significant clinical signs of immunodeficiency syndrome (AIDS) for 8 years and 4 months of asymptomatic phase, the Petaluma-infected cat exhibited severe stomatitis/gingivitis, anorexia, emaciation, hematological and immunological disorders such as severe anemia, lymphopenia, thrombocytopenia, and decrease of CD4/CD8 ratio to 0.075, and finally died with hemoperitoneum at 8 years and 8 months post-infection. Histopathological studies revealed that the cat had systemic lymphoid atrophy and bone marrow disorders indicating acute myelocytic leukemia (aleukemic type). Plasma viral titer of the cat at AIDS phase was considerably high and anti-FIV antibody titer was slightly low as compared with the other FIV-infected cats. In addition, immunoblotting analysis using serially collected serum/plasma samples of these cats revealed that antibodies against FIV proteins were induced in all the infected cats, however in the Petaluma-infected cat anti-Gag antibodies disappeared during the asymptomatic period. These results suggested that plasma viral load and anti-FIV Gag antibody response correlated with disease progression, and supported FIV-infected cats as a suitable animal model of human AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Further development of a recombinant feline herpesvirus type 1 vector expressing feline calicivirus immunogenic antigen.

We previously reported the attenuation of thymidine kinase (TK) deficient mutant (C7301dlTK) of feline herpesvirus type 1 (FHV-1) in cats and the construction of a recombinant FHV-1 (C7301dlTK-Cap) inserted a precursor capsid gene of feline calcivirus (FCV) into the TK deletion locus of the C7301dlTK. In this study, we constructed a further improved recombinant FHV-1 (dlTK(gCp)-Cap) carrying a putative FHV-1 gC promoter sequence upstream of the FCV precursor capsid gene of the C7301dlTK-Cap. Growth kinetics of the dlTK(gCp)-Cap in cell cultures was similar to those of C7301dlTK and C7301dlTK-Cap. A strong expression of FCV immunogenic antigen by dlTK(gCp)-Cap was confirmed by indirect immunofluorescence and enzyme-linked immunosorbent assays. In addition, one vaccination with dlTK(gCp)-Cap protected cats more effective against subsequent virulent FCV challenge than that with C7301dlTK-Cap.

Animals↗
PubMed1998

New quantitative methods for detection of feline parvovirus (FPV) and virus neutralizing antibody against FPV using a feline T lymphoid cell line.

Previously, we reported that a feline T lymphoid cell line, FL74 cells, was very sensitive to feline parvovirus (FPV) infection. In the present study, we developed new quantitative methods for detection of FPV and virus neutralizing antibody against FPV using FL74 cells. The methods presented here were very simple and applicable to both canine parvovirus and feline panleukopenia virus.

Animals↗
PubMed1998

[The influence of age and sex on the results of otosclerosis surgery].

The influence of age and sex on auditory improvement after stapes surgery was investigated retrospectively on 127 otosclerotic ears (99 subjects) that were followed up for 6 months postoperatively. The prostheses used were the Shuknecht-type Teflon wire piston (87 ears), the House-type wire loop (29 ears), and the Cawthone-type Teflon piston (11 ears). While closure of the air-bone gap after surgery was good at 2 kHz, it was poor at 8 kHz and frequencies lower than 1 kHz, and especially poor at 250 Hz. At all frequencies, both air and bone thresholds were significantly improved by the surgery, but the greatest improvements in air and bone thresholds resulted from the use of Teflon wire pistons. Ears receiving Teflon wire prostheses were divided into 5 age groups: under 20 years, 20-29, 30-39, 40-49, and 50 or above. Both air and bone thresholds at higher frequencies before surgery worsened with increasing age. However, there were no significant differences among age groups in the postsurgical improvement of either air or bone thresholds. Similarly, no gender-related differences in either air or bone thresholds were recognized postsurgically. The authors speculate that light cases of otosclerosis are common among Japanese patients, while severe cases are rare even among the elderly.

Adult↗
PubMed1998

[Contrast enhanced color Doppler sonogram of liver tumors: a color-filled pattern in the late phase].

In the present report, a "color-filled pattern", the late phase effect in the intra-venous contrast enhanced color Doppler sonography is introduced, using SH/TA-508 as the contrast agent. This pattern is defined as an image of a tumor area filled with color in contrast to the surrounding liver. After contrast enhancement, the detectability of a "feeding artery" increased. And also "color filled pattern" appeared in 14 of the 21 hepatocellular carcinomas but none of the nine other liver tumors. In conclusion, contrast enhancement increases the detectability of a "feeding artery" and improves the sensitivity for HCC with color Doppler sonography. A "color-filled pattern" is also effective in the diagnosis of HCC because it requires no technical skill and shows high specificity.

Animals↗