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Biomedical subjects

M Hirata

Publications and source records attributed to M Hirata.

At least 343 records · Page 19Linked to original sources
PubMed1993

Low prevalence of hepatitis C virus infection among hospital staff and acupuncturists in Kyushu, Japan.

During 1987 and 1988, samples of serum were collected from 1097 members of the staff of four prefectural hospitals in Miyazaki prefecture and from 183 acupuncturists in Fukuoka City, Japan. The staff included both surgical and non-surgical doctors, radiographers, physiotherapists, nurses, laboratory technicians and others. The samples were tested for the following hepatitis C virus (HCV) markers; antibodies to c100 (anti-c100) by means of enzyme-linked immunosorbent assay (ELISA) with supplementary recombinant immunoblot assay as well as antibodies to the GOR epitope (anti-GOR), also by means of ELISA. Anti-c100 was present in 1.7% of the doctors, radiographers and physiotherapists, in 1.3% of the nurses and in 2.2% of the acupuncturists. These prevalences were slightly higher than those in the controls but the differences were not statistically significant. Anti-c100 was not detected in any laboratory technician or other member of the hospital staff. For an accurate determination of the prevalence of HCV infection, the combined rate of anti-c100 and/or anti-GOR was also calculated. The combined prevalence of HCV infection was 4.3% in medical staff, 2.2% in nurses and 5.5% in acupuncturists. The prevalence of HCV infection among those with direct contact with patients was higher than that of the controls but without statistical significance. In the cohort we examined, the occupational risk of HCV infection was low.

Acupuncture Therapy↗
PubMed1993

Effects of p-phenylenediamines and adriamycin on primary culture of rat skeletal muscle cells.

In vitro toxicity of p-phenylenediamine derivatives and adriamycin were examined using cultured rat myofibers prepared by the selective plating method, with slight modification. When the myofibers were cultured for 2 days with 100 microM N,N,N',N'-tetramethyl p-phenylenediamine, atrophy and/or swelling of the cells were observed, and the toxic effect was reduced as the number of N-methyl groups in the phenylenediamine molecule was decreased. Adriamycin, at concentrations of greater than 0.25 microM, caused cell injury. Decline of cellular creatine phosphokinase activities generally preceded the apparent morphological changes. The primary culture of rat myofibers responded sensitively to the agents which were myotoxic in vivo.

Animals↗
PubMed1993

Inhibition of PMA-induced, LFA-1-dependent lymphocyte aggregation by ADP ribosylation of the small molecular weight GTP binding protein, rho.

Botulinum C3 exoenzyme specifically ADP-ribosylates a group of ras-related small molecular weight GTP-binding proteins, rho, and inhibits their biological activity. Using this enzyme, we examined the function of rho in PMA-induced activation of lymphocyte function-associated antigen-1 (LFA-1) in a B lymphoblastoid cell line, JY. Northern blot analysis revealed that among the three rho genes, rhoA mRNA was predominantly expressed in JY cells. Consistently, only one [32P]ADP-ribosylated band was found when the lysate of the cells was subjected to ADP ribosylation by C3 exoenzyme. When the cells were cultured with C3 exoenzyme, this substrate was ADP-ribosylated in situ in a time- and concentration-dependent manner. Concomitant with this ADP ribosylation, PMA-induced LFA-1/intercellular adhesion molecule (ICAM)-1-dependent aggregation of JY cells was inhibited. This inhibition was blocked by prior treatment of the enzyme with an anti-C3 monoclonal antibody, and overcome by stimulation with higher concentrations of PMA. The C3 exoenzyme-induced inhibition was not affected by shaking of the cell suspension, while inhibition of aggregation by cytochalasin B was abolished by this procedure, suggesting that the inhibitory effect of the C3 exoenzyme treatment was not due to decrease in cell motility. The C3 exoenzyme treatment affected neither protein phosphorylation in JY cells before and after PMA stimulation, nor affected surface expression of LFA-1 and ICAM-1. These results suggest that rhoA protein works downstream of protein kinase C activation linking PMA stimulation to LFA-1 activation and aggregation in JY cells.

ADP Ribose Transferases↗
PubMed1993

[Pleural washing with povidone-iodine for treatment of empyema].

In this paper, we report two successful cases of empyema treated by pleural washing with povidone-iodine solution. In these two cases, empyema was caused by secondary infection of multi-drug resistant Pseudomonas aeruginosa. First, we replaced intrathoracic drainage tube and washed intrathoracic space with 500-1000 ml saline containing antibiotics (tobramycin, aztreonam) every 8 hours for 10-14 days. But, cultural studies of pleural effusion were positive even after this treatment. So, we tried pleural washing with warm povidone-iodine solution 1:20 diluted with saline every 8 hours. Surprisingly, after 3 days treatment, cultural studies of the pleural effusion became negative. This pleural washing method with povidone-iodine was very effective for treatment of empyema patients.

Aged↗
PubMed1993

[Immunogenicity of Chinese hamster ovary cell derived HB vaccine--a comparative study with yeast derived HB vaccine].

To evaluate the immunogenicity of the Chinese hamster ovary cell derived HB vaccine (CHB), CHB and yeast derived HB vaccine (YHB) were given to 110 medical students divided into four groups. CHB was given to group A subcutaneously (0.5 ml, 3 times) and to group B intradermally (0.125 ml, 3 times). YHB was given to group C (Y company) and to group D (Z company) subcutaneously (0.5 ml, 3 times). The anti-HBs positive rate at 7 months was 85.7% in group A, 95.8% in group B, and 100% in groups C and D. The percentage responding with high anti-HBs concentration (> or = 100 mIU/ml by RIA) at 7 months was 67.9% in group A, 79.2% in group B, 58.3% in group C and 63.3% in group D. Thus, although the anti-HBs positive rate was rather low when CHB was given subcutaneously, it was almost the same as YHB when given intradermally. The percentage of high responders to CHB given both subcutaneously and intradermally was high compared to YHB. These data suggest that CHB has almost the same immunogenicity to the conventional YHB.

Adult↗
PubMed1993

Antimicrobial activity of rabbit CAP18-derived peptides.

A cationic antimicrobial protein of 18 kDa (CAP18) was originally isolated from rabbit granulocytes by using as an assay the agglutination of Re-lipopolysaccharide-coated erythrocytes. The C-terminal 37 amino acids of CAP18 (CAP18(106-142)) make up the lipopolysaccharide-binding domain. Synthetic CAP18(106-142) has broad antimicrobial activity against both gram-positive (50% inhibitory concentration, 130 to 200 nM) and gram-negative (50% inhibitory concentration, 20 to 100 nM) bacteria. Susceptible strains include Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhimurium. Antimicrobial activity is highly dependent on peptide structure. Although a 32-amino-acid peptide resulting from the truncation of 5 amino acids from the C terminus of CAP18(106-142) is highly active, other fragments of CAP18(106-142), including CAP18(106-142) with a truncated N terminus, do not exhibit antimicrobial activity. Unlike previously characterized antimicrobial peptides derived from granulocyte proteins, CAP18(106-142) is active in serum. CAP18(106-142) or a derivative peptide may have therapeutic potential for bacterial sepsis.

Agglutination Tests↗
PubMed1993

Synergism between muramyl dipeptide and lipopolysaccharide in the inhibition of glycosaminoglycan synthesis in cultured rat costal chondrocytes.

The effect of synthetic muramyl dipeptide on glycosaminoglycan synthesis in cultured rat costal chondrocytes was examined. Muramyl dipeptide alone had no effect on the glycosaminoglycan synthesis of rat chondrocytes, whereas Escherichia coli lipopolysaccharide and interleukin 1 alpha inhibited glycosaminoglycan synthesis in a dose dependent manner. Muramyl dipeptide, when added to chondrocyte cultures in the presence of lipopolysaccharide, enhanced the lipopolysaccharide induced inhibition of glycosaminoglycan synthesis in a dose dependent manner. Adjuvant active analogues of muramyl dipeptide, but not adjuvant inactive analogues, also enhanced the lipopolysaccharide induced inhibition of glycosaminoglycan synthesis. In combination with muramyl dipeptide, to inhibit glycosaminoglycan synthesis, lipopolysaccharide could be replaced with the synthetic lipid A, an active principle of lipopolysaccharide. These results show that the muramyl dipeptide portion of bacterial peptidoglycan enhances the susceptibility of rat chondrocytes to the lipid A portion of bacterial lipopolysaccharide, and therefore the interaction between chondrocytes and bacterial cell wall components might be involved in damaging the cartilage in inflammatory joint diseases.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1993

Latency of the Achilles tendon reflex for detection of reduced functions of the peripheral nervous system in workers exposed to lead.

The latency of the soleus muscle potential, evoked by a tap of the Achilles tendon, was used in the mass assessment of healthy male workers exposed to lead. Three groups were studied: a control, a low exposure, and a high exposure group. Mean blood lead concentrations were 9.3, 19.2, and 53.1 micrograms/100 ml respectively. Latencies were adjusted for age and height and then compared among the three groups. The mean corrected latency of the high exposure group showed a 4% increase compared with the other two groups (p < 0.01). The latencies of the other two groups showed no between group differences. These results were consistent with previous neurophysiological studies done by many researchers on workers exposed to lead. They suggested that nerve conduction velocities decreased from 3 to 13% among workers whose mean blood lead concentrations were more than 30 micrograms/100 ml. The method was simple, time conserving, non-invasive, and non-aversive, and provided a quantitative measure of the nerve conduction velocities of peripheral nerves. Thus it may be useful for early detection of occupationally related impairment of peripheral nerves.

Achilles Tendon↗
PubMed1993

Synthesis and characterization of 11C-labeled fluoroclorgyline: a monoamine oxidase A specific inhibitor for positron emission tomography.

A new radioligand for monoamine oxidase type A (MAO-A), [11C]fluoroclorgyline, was synthesized from its desmethyl precursor by N-methylation reaction using [11C]methyl iodide with a radiochemical yield of 75-85%. The radiochemical purity of the product was more than 99% and the specific radioactivity was 7.4-18.5 GBq/micromol. The in vivo tissue distribution studies of [11C]fluoroclorgyline in mice demonstrated its high initial uptake and prolonged retention in the brain, comparable to those of [11C]clorgyline. A selective interaction with MAO-A in the accumulation of [11C]fluorclorgyline was confirmed by a competition experiment performed with the MAO-A specific inhibitor,clorgyline, and MAO-B specific inhibitor, l-deprenyl. These very desirable characteristics of [11C]fluoroclorgyline suggested that its 18F labeled counterpart, [18F]fluoroclorgyline, would have great potential as a longer-lived alternative to 11C labeled clorgyline for in vivo studies of MAO-A in the human brain with positron emission tomography (PET).

Animals↗
PubMed1993

Clonidine improves central attenuation of the baroreflex in spontaneously hypertensive rats.

To determine whether clonidine can improve the central alteration of the baroreflex in SHR, the centrally cut end of the aortic depressor nerve was electrically stimulated in SHR with intravenously administered clonidine. Aortic depressor nerve (ADN) stimulation elicited depressor and sympatho-inhibitory responses in a frequency-dependent manner in WKY and SHR. These responses were significantly smaller in SHR than in WKY. The attenuated depressor and sympatho-inhibitory responses to ADN stimulation in SHR were restored following i.v. injections of clonidine, although the drug did not affect the responses to ADN stimulations in WKY. These findings suggest that clonidine can improve central attenuation of the baroreflex in hypertension.

Adrenergic Fibers↗
PubMed1993

Effect of phenobarbital and other model inducers on cytochrome P450 isoenzymes in primary culture of dog hepatocytes.

1. The effects of phenobarbital (PB), beta-naphthoflavone (beta-NF), omeprazole (Omep) and rifampicin (Rif) on drug-metabolizing activities in dog hepatocytes, cultured with William's medium E, were examined. 2. The drug metabolizing activities of the hepatocytes decreased during culture; 7-ethoxycoumarin O-deethylase (ECOD) activity was nearly 70% of initial value at 72 h, but 7-methoxycoumarin O-demethylase (MCOD), 7-propoxycoumarin O-depropylase (PCOD), progesterone 6 beta-hydroxylase (6 beta-OH-P), progesterone 16 alpha-hydroxylase (16 alpha-OH-P), progesterone 21-hydroxylase (21-OH-P), 7-ethoxyresorufin O-deethylase (EROD) activities and total cytochrome P450 content were approx. 50%. 3. When the hepatocytes were cultured with PB, the enzyme activities increased time- and dose-dependently. MCOD, ECOD and PCOD activities increased 5-8 fold with 2 mM PB in 96 h. Similar results were obtained for 6 beta-OH-P, 16 alpha-OH-P and 21-OH-P activities, and total cytochrome P450. The effect of PB was abolished when 2.5 microM cycloheximide or 0.1 microM actinomycin D was included in the culture. 4. Treatment of hepatocytes with 40 microM beta-NF for 72 h resulted in 25-fold elevation of EROD activity. beta-NF enhanced PCOD activity approx. six-fold, while ECOD increased only slightly, and 7-MCOD negligibly. 5. Omep (100 microM) increased EROD activity nearly 10-fold, and 25 microM Rif increased 6 beta-OH-P activity approx. 8-fold, but ECOD only slightly. 6. Western blot analysis of microsomes from cultured dog hepatocytes with anti-rat CYP 2B1 antibodies indicated that PB increased an immunochemically-reactive protein. The protein showed the same mobility as the major dog P450 isozyme (cytochrome P450 PBD-2 or CYP 2B11) purified from liver microsomes of PB-treated male beagle dog. In a similar manner, induction of cytochrome P450 PBD-1 (CYP 3A12) by PB was confirmed.

7-Alkoxycoumarin O-Dealkylase↗
PubMed1993

The long-term effect of primary disease on cadaver-donor renal transplant recipients.

1. Graft survival was similar at one year for the various diseases, but at 3 years, a 16% divergence was noted among diseases. IGAN patients had the highest graft survival rate. 2. Graft survival rates of IGAN, ALP, and PC in Black and White patients were similar, but in all other diseases, a high loss rate was seen after one year among Black patients. 3. Patient survival was almost identical for the various diseases among Whites and Blacks. 4. SLE patients with DR2 or DR3 had higher graft survival rates than SLE patients without these groups (p < 0.05 in Whites). 5. IDDM patients with DR3 or DR4 had higher graft survival rates than IDDM patients without these groups (p < 0.05 in Whites, p = ns in Blacks). 6. Nephrosclerosis patients with DR2 or DR4 had higher graft survival rates than those who did not (p = ns in Whites, p < 0.05 in Blacks). 7. CGN patients with DR1 had higher graft survival rates than CGN patients without DR1 (p < 0.00005 in Whites). 8. IDDM patients with SPK transplants had higher graft survival rates than IDDM patients grafted with a KAT (p < 0.000001). In recent years, almost 30% of IDDM patients had SPK transplants. 9. Patients with SPK grafts compared to KAT were younger, White, were more often DR3/4, and worked full-time. 10. The SPK effect was seen only at the excellent centers. At all other centers, SPK and KAT patients had the same graft survival rates.

Adolescent↗
PubMed1993

The acute toxicity of allyl chloride by subcutaneous injection in mice.

Male ICR mice were administered allyl chloride at dose of 496 mg/kg, 600 mg/kg, 720 mg/kg, 864 mg/kg or 1037 mg/kg by a single subcutaneous injection. Sixteen of 25 mice died by the 7th day after the injection and LD50 was calculated 621 mg/kg body weight (95% C.I.: 522-739 mg/kg). A marked congestion with severe hemorrhage and edema were observed in the lung. Liver and kidney damages were also found, and these were characterized by the dilated sinusoids, degenerative change of hepatic cells, and focal necrosis in the liver; and necrosis of epithelium in convoluted tubules of the kidneys. Nine mice have survived by the 7th day after the injection and all of them showed a various degree of damages in the testes. The testicular lesions could be classified into two types. One type of the lesion was characterized by degeneration and exfoliation of germ cells, appearance of polynuclear giant cells in the seminiferous tubules, and mild proliferation of Leydig cells in the interstitium. In another type of the lesion, all type of cells in tubules, including Sertoli cells, and Leydig cells became necrotic. This is the first study reporting the testicular toxicity of allyl chloride.

Allyl Compounds↗
PubMed1993

[A case of exogenous lipoid pneumonia probably due to domestic insecticide].

A 61-year-old female was admitted to our hospital because of cough, hemosputum and right chest pain. The P-A and L-R chest films revealed focal consolidation in the right upper filed and mass-like shadow in the right S3. Transbronchial lung biopsy specimens showed collections of lipid-laden macrophages. The lipid material of macrophages in broncholaveolar lavage fluid was stained yellow-orange with Sudan IV. The patient had no difficulty in swallowing and had no history of regular use of oily drugs. Fiberoptic bronchoscopy and chest CT showed no obstruction of bronchi. She had used much domestic insecticide with the doors closed before going to bed every summer and autumn for 10 years. We concluded that the domestic insecticide containing mineral oil had resulted in exogenous lipoid pneumonia. Her symptoms and abnormal shadows in chest X-ray film disappeared soon after antimicrobial chemotherapy was started. She is now healthy without recurrence.

Female↗
PubMed1993

[Structure and function of the prostanoid receptors in cardiovascular system].

Recently, cDNAs for TXA2 and PGE2 (EP3 and EP2) receptors have been cloned and their primary structure elucidated. They belong to a G-protein coupled, rhodopsin-type receptor superfamily. The TXA2 receptor has been most extensively analyzed biochemically, pharmacologically and molecular biologically. Its genomic structure has also been elucidated. The EP3 receptor has several isotypes, which are generated by alternative splicing at its C-terminus. These isotypes show different efficiency in their coupling to G-proteins. EP2 receptor shares some features with adrenergic receptors in its cytoplasmic loop. The PGI2 receptor protein shares similar characteristics with TXA2 and PGE2 receptors. Molecular characterization of the prostanoid receptor will promote understanding of the roles played by these bioactive arachidonate metabolites and help developing new treatment strategies in disorders of the circulation system.

Amino Acid Sequence↗
PubMed1993

Different courses of granulomatous reactions around Schistosoma japonicum eggs in three strains of mice.

Tissue reaction around Schistosoma japonicum eggs was studied after implantation into 3 strains of mice. When freshly laid eggs were implanted into the livers of C57BL/6, CBA/J, and BALB/c mice, the tissue reaction, which could be divided into 3 stages, i.e., abscess formation, inflammatory stage, and fibrous stage, differed in persistence and reactivity according to the strain. This was true especially during the later 2 stages. In BALB/c mice, the inflammatory stage ended earlier. In CBA/J mice, it continued for the longest period and the subsequent fibrosis was the most marked. In C57BL/6 mice, the period of persistence of this inflammatory stage was intermediate, but these mice showed the highest degree of inflammatory reaction. When footpad reactions were tested, the delayed-type hypersensitivity reaction was generally comparable with the morphometric analysis. In presensitized mice implanted with lyophilized eggs, tissue reactivity was analogous to the fibrous stage of freshly laid egg-implanted mice. In addition, there was an inverse relationship between antibody level and granuloma size, particularly at later reactions. The analysis of experimental granuloma formation presented in this report contributes to the study of stage-specific regulation.

Animals↗
PubMed1992

Sexual transmission of hepatitis C virus among female prostitutes and patients with sexually transmitted diseases in Fukuoka, Kyushu, Japan.

The authors investigated the prevalence of antibody to hepatitis C virus (anti-HCV) in 404 female prostitutes, 428 clinic patients with a history of at least one episode of sexually transmitted disease, and 8,944 blood donors who served as the controls. All subjects were Japanese, and all studies were carried out in Fukuoka, Kyushu, Japan, in 1989. The prevalence of anti-HCV was significantly higher in the prostitutes (6.2%), in the female patients with sexually transmitted diseases (6.1%), and in the male patients with sexually transmitted diseases (2.9%) than in the controls (1.5%). Prevalence of anti-HCV increased with age in prostitutes and in the controls. The prevalence of anti-HCV in those who had been involved in prostitution for 1 year or more (8.1%) was higher than in those who had been involved in prostitution for less than 1 year (1.4%), but the difference was not statistically significant. One of the 152 anti-HCV negative prostitutes seroconverted between 1 and 2 years later. Among the subjects with sexually transmitted diseases, patients with a history of at least one episode of syphilis had a significantly higher prevalence of anti-HCV (4.4%) than the controls. Patients with acute urethritis and cervicitis also showed a high prevalence of anti-HCV (3.6% and 6.7%, respectively). These data support the possibility of sexual transmission of hepatitis C virus.

Adolescent↗