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Biomedical subjects

H Hotta

Publications and source records attributed to H Hotta.

At least 91 records · Page 5Linked to original sources
PubMed1995

MDCK cell cultures supplemented with high concentrations of trypsin exhibit remarkable susceptibility to influenza C virus.

Multiplication of influenza C virus in MDCK cell cultures increased with increasing concentrations of trypsin up to 160 micrograms/ml, whereas maximum growth of influenza A virus in the same culture was observed at a concentration of 10 micrograms/ml. In the presence of 160 micrograms of trypsin per ml MDCK cells showed the same or even higher susceptibility to various strains of influenza C virus compared with HMV-II cells, a human melanoma cell line that has been reported to have high susceptibility to the virus. Complete cleavage of the HE precursor protein of MDCK-grown influenza C virus into HE1 and HE2 subunits was achieved by trypsin at a concentration of 160 micrograms/ml, whereas only partial cleavage was observed at 10 micrograms/ml. The present results thus demonstrate that MDCK cell cultures supplemented with trypsin at a concentration of 160 micrograms/ml become highly susceptible to influenza C virus.

Animals↗
PubMed1995

Significance of detection of enterovirus RNA in myocardial tissues by reverse transcription-polymerase chain reaction.

Enteroviruses are known to have association with human myocarditis and dilated cardiomyopathy (DCM). We screened biopsy specimens from patients with active myocarditis or DCM, and myocardial tissues from autopsy cases without cardiac diseases using polymerase chain reaction (PCR) gene amplification. Positive enteroviral signals were demonstrated from 4 of 5 patients with active myocarditis (80%), 7 of 42 patients with DCM(17%) and 3 of 27 autopsies (11%). Out of 7 PCR positive patients with DCM, 3 cases showed hypertrophy and disarray of cardiocytes, fibrosis in the interstitium, and a few inflammatory infiltrates. The remaining 4 cases with DCM and 3 PCR positive autopsy cases did riot exhibit histological findings compatible with those in myocarditis. Our results support the observations that enteroviruses are common aetiologic agents of myocarditis, and some cases of DCM. Our results also suggest the possibility that in some cases enteroviruses may persist in the myocardium without causing apparent pathological changes.

Adult↗
PubMed1995

Stimulatory effect of butoctamide hydrogen succinate on REM sleep in normal humans.

1. The efficacy of butoctamide hydrogen succinate (BAHS) was compared with that of nitrazepam on the basis of the polysomnograms and the subjective assessments. 2. Twelve healthy male students were divided into three groups consisting of 4 subjects each with were administered BAHS 600 mg, nitrazepam 5 mg, and BAHS 600 mg + nitrazepam 5 mg, respectively. 3. Polygraphic recordings were made for 8 consecutive nights for each subject, and the polysomnograms were evaluated by computerized automatic analysis using the interval histogram method. 4. An inert placebo was administered on the first 3 nights and on the seventh and eighth nights, and the test article regimen was administered on the fourth, fifth and sixth nights. 5. The test articles and the placebo were administered orally at 22:30 hr, and the recording of polysomnograms was started at 23:00 hr and ended at 8:00 hr the next morning. 6. The subjects were requested to fill out the subjective assessment of sleep before falling asleep and after arising the next morning. 7. BAHS increased REM sleep and decreased stage 2 sleep significantly; however, it failed to affect stage 1, 3 or 4 sleep. 8. Nitrazepam increased significantly the total sleep time and stage 2 sleep but decreased significantly the stage 3 sleep and decreased slightly the stages 1, 4 and REM sleep. 9. The combined treatment with BAHS and nitrazepam did not alter the sleep parameters except for increasing the total sleep time. 10. No obvious changes were observed in the subjective assessments after administration of the drugs. 11. These findings suggest that BAHS results in a unique sleep pattern different from benzodiazepines, and that BAHS may be suitable for treating insomnia in elderly patients and those with drug abuse, manic-depressive illness or schizophrenia.

Adult↗
PubMed1995

Chlorzoxazone is metabolized by human CYP1A2 as well as by human CYP2E1.

Chlorzoxazone, a muscle-relaxing drug, is metabolized by carbon-hydroxylation at position 6. Chlorzoxazone has been suggested as an in vivo probe for CYP2E1. We studied the specificity of such a substrate using vaccinia virus expressed human P450 forms and the effect of inhibitors for chlorzoxazone metabolism by human liver microsomes. The 6-hydroxylation of chlorzoxazone was mediated by CYP1A2 as well as by CYP2E1. The Km value of CYP1A2 and CYP2E1 for the reaction was 5.69 microM and 232 microM, respectively. However, the Vmax value of CYP2E1 for the reaction was approximately 8.5-fold higher than that of CYP1A2. The CYP1A inhibitor, alpha-naphthoflavone, as well as the CYP2E1 inhibitor, diethyldithiocarbamate, decreased chlorzoxazone 6-hydroxylation at a low substrate concentration by human liver microsomes. Our results raise questions about the suitability of chlorzoxazone as an in vivo probe for hepatic CYP2E1 activity. In human liver microsomal samples, the Km = 40 microM was different from either the Km of CYP1A2 or CYP2E1. We think that this discrepancy is due to the co-expression of similar levels of CYP1A2 and CYP2E1 in human liver. Furthermore, it is suggested that the role of CYP2E1 in 6-hydroxychlorzoxazone formation at the physiological chlorzoxazone concentration of 30-60 microM is almost the same when compared to that of CYP1A2.

Benzoflavones↗
PubMed1995

Detection of measles virus nucleoprotein mRNA in autopsied brain tissues.

By means of RT-PCR, a portion of measles virus (MV) mRNA encoding nucleoprotein (NP) could be detected in 11 (18%) of 61 brain tissue samples obtained from administrative autopsy cases, who apparently had not suffered from subacute sclerosing panencephalitis (SSPE)-like central nervous system disorders. Most of the brain-derived NP sequences showed significant asynonymous nucleotide substitutions when compared with wild-type MV isolates and SSPE virus. Our present results suggest that MV commonly persists in the human brain without causing apparent clinical symptoms, probably due to decreased virus replication.

Adolescent↗
PubMed1995

Cellular lipid and fatty acid compositions of Burkholderia pseudomallei strains isolated from human and environment in Viet Nam.

Viet nam is known as an endemic area of melioidosis but its etiologic agent originated in Viet nam was not extensively studied. For the first time, we analyzed the cellular lipid and fatty acid compositions of 15 Vietnamese isolates of Burkholderia pseudomallei, 10 from humans and 5 from the environment. Cellular lipid compositions were analyzed by two-dimensional thin-layer chromatography on silica gel G plates. Cellular fatty acid methyl esters were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The major lipids in all the isolates were phosphatidylglycerol (PG), two forms of phosphatidylethanolamine (PE-1 and PE-2), and two forms of ornithine-containing lipid (OL-1 and OL-2). PE-1 contained non-hydroxy fatty acids at both sn-1 and -2 positions, while PE-2 possessed 2-hydroxy fatty acids and non-hydroxy fatty acids in a ratio of 1:1. Since snake venom phospholipase A2 digestion of PE-2 liberated 2-hydroxy fatty acids, it was confirmed that these acids are at the sn-2 position of glycerol moiety. In both OL-1 and OL-2, amide-linked fatty acid was 3-hydroxy palmitic acid (3-OH-C16:0), while ester-linked fatty acids were non-hydroxy acids in OL-1 and 2-hydroxy acids in OL-2. The total cellular fatty acid compositions of the test strains were characterized by the presence of 2-hydroxy palmitic (2-OH-C16:0), 2-hydroxy hexadecenoic (2-OH-C16:1), 2-hydroxy octadecenoic (2-OH-C18:1), 2-hydroxy methylene octadecanoic (2-OH-C19CPA), 3-hydroxy myristic (3-OH-C14:0) and 3-hydroxy palmitic (3-OH-C16:0) acids. There were significant differences in the concentration of hexadecenoic (C16:1), methylene hexadecanoic (C17CPA), octadecenoic (C18:1) and methylene octadecanoic (C19CPA) acids among the Vietnamese isolates of B. pseudomallei. However, no significant difference was observed in cellular lipid and fatty acid components between strains of human and environmental origins.

Adolescent↗
PubMed1995

Frequent detection of hepatitis C virus subtype 3a (HCV-3a) isolates in Thailand by PCR using subtype-specific primers.

By means of a polymerase chain reaction (PCR) method using subtype-specific primers for hepatitis C virus (HCV) subtypes 1a, 1b, 2a, 2b and 3a, the prevalence of each subtype among HCV isolates in Chiang Mai, Thailand, was determined. HCV-3a appeared to be the most common subtype in blood donors, and was also frequently found in patients with liver disease. HCV-1b, but not HCV-2a or -2b, was also commonly found in this area, while a considerable percentage of the total HCV isolates still remained unclassifiable by the above methods. Serotype analysis of the HCV isolates using C14-1 and C14-2 recombinant peptides revealed that HCV-3a was likely to carry an antigenic determinant(s) different from those of the major types 1 (HCV-1a and -1b) and 2 (HCV-2a and -2b).

Adult↗
PubMed1995

Transfer of two Burkholderia and an Alcaligenes species to Ralstonia gen. Nov.: Proposal of Ralstonia pickettii (Ralston, Palleroni and Doudoroff 1973) comb. Nov., Ralstonia solanacearum (Smith 1896) comb. Nov. and Ralstonia eutropha (Davis 1969) comb. Nov.

Based on the results of phenotypic characterization, cellular lipid and fatty acid analysis, phylogenetic analysis of 16S rDNA nucleotide sequences and rNA-DNA hybrization, Burkholderia pickettii, Burkholderia solanacearum and Alcaligenes eutrophus are transferred to the new genus Ralstonia, and Ralstonia pickettii (Ralston, Palleroni and Doudoroff 1973) comb. nov., Ralstonia solanacearum (Smith 1896) comb. nov., and R. eutropha (Davis 1969) comb. nov. are proposed. The type species of the new genus is R. pickettii. Type strain of R. pickettii is ATCC 27511T, of R. solanacearum is ATCC 10696T, and of R. eutropha is ATCC 17697T.

Alcaligenes↗
PubMed1995

Enzyme-linked immunosorbent assay (ELISA) using a glycolipid antigen for the serodiagnosis of melioidosis.

The serodiagnosis of melioidosis is commonly performed with tests using protein or polysaccharide as antigen. However, due to the low sensitivity, specificity and difficulty in the preparation of the antigens, more simple, precise and reproducible diagnostic tests were required. A purified glycolipid antigen (GL) which is a specific lipid component of Burkholderia pseudomallei has been used in an ELISA. With this antigen, specific immunoglobulin G (IgG) was detected in 49 out of 50 melioidosis sera. IgG was also detected in 2 out of 185 (Japanese) and 16 out of 181 (Vietnamese) control sera. Thus, the sensitivity was 98.0%, and specificity was 98.9% and 91.1% in the Japanese and Vietnamese sera, respectively. When the ELISA and indirect haemagglutination (IHA) tests were combined, a sensitivity of 100% and specificity of 97.8% were achieved. The advantages of the glycolipid antigen are ease of preparation, stability, high sensitivity and specificity.

Antigens, Bacterial↗
PubMed1995

The effects of aging on the rat bladder and its innervation.

1) Measurements of the cystometrogram, of the responsiveness of bladder muscle to pelvic nerve efferent stimulation and of the sensitivity of the pelvic nerve afferents to pressure and volume during distensions have been made in the bladders of young adult (2-3 months) and aged (26-29 months) rats, anesthetized with mixtures of urethane and chloralose. 2) The pressure-volume relationship differed in young adult and aged rats. The bladders of the aged rats held up to nearly six times the volume of the young animals, and these volumes were accommodated at lower pressures in the aged animals. The pressure at which micturition contractions appeared was similar in young adult and aged animals. 3) The passive pressure associated with each of a series of distending volumes was recorded when a pelvic nerve was cut unilaterally. The distal cut end of this cut pelvic nerve was stimulated for 10 s at 20 Hz, using square wave pulses of 10 V and 1.0 ms. The active pressure-volume relationship was constructed from this data. Both the active and the passive relationships were shifted to the right in the aged animals, and it was evident that aging was associated with a reduction in the maximal pressure generated during pelvic nerve stimulation. Also the change in intravesical pressure induced by bladder contraction was less in aged animals. 4) The most sensitive mechanoreceptor afferents appear to have pressure and volume thresholds that do not change significantly during aging. While the distension-sensitive afferents in the pelvic nerve appear to have a similar sensitivity to intravesical pressure in young adult and aged rats, they were less able to monitor volume in the aged animals. The stimulus response relationship for volume was often less steep in the aged animals. 5) In this study, aging was shown to be associated with a large increase in bladder volume and a reduced sensitivity of pelvic nerve afferents to volume, and a reduced ability to raise bladder pressure during contraction of bladder smooth muscle. The changes in bladder function associated with aging are discussed.

Aging↗
PubMed1995

Associated injuries and mechanism of atlanto-occipital dislocation caused by trauma.

Injuries associated with traumatic atlanto-occipital dislocation (AOD) leading to death were analyzed in 11 patients, nine injured by traffic accidents, of which five were victims of car-pedestrian accidents. On admission, unconsciousness and respiratory arrest were noted in all patients, and cardiac arrest in nine. Skull and cervical roentgenograms revealed enlargement of the retropharyngeal space due to injury of the vertebral artery or its branches in nine patients, atlanto-axial dislocation (C-1-C-2 separation) in four, and skull fracture in four. Computed tomography demonstrated subarachnoid hemorrhage (SAH) in the upper cervical and posterior fossa in nine patients, fourth ventricular hematoma in seven, and atlas fracture in three. SAH and ventricular hematoma were due to craniocervical injury. Other common injuries were injury of face and head excluding the mandibular region in 10 patients, mandibular fracture in three, severe chest injuries in eight, and intraperitoneal bleeding in two. The overall outcome was poor. Nine patients died within 13 hours of admission, one was diagnosed as brain dead 8 days after the accident, and the other one survived in a persistent vegetative state. Early death is probably caused by associated severe injuries, i.e. chest injuries and intraperitoneal bleeding rather than AOD. Although injury of the mandibular region is known to be associated with AOD, head, breast, and abdominal trauma may also lead to neck hyperextension-flexion in various directions. Whatever the direct cause, a distractive force to the craniocervical joint by hyperextension-flexion appears to be important in the mechanism of AOD.

Accidents, Traffic↗
PubMed1994

Molecular cloning of the murine homologue of CD63/ME491 and detection of its strong expression in the kidney and activated macrophages.

The mouse homologue of CD63/ME491 (Mu-CD63) was molecularly cloned and analyzed. Mu-CD63 exhibited a strikingly high similarity to CD63/ME491 and the rat homologue. Northern blot analysis revealed that Mu-CD63 mRNA was expressed strongly in the kidney of adult mice, especially in the glomerulus fraction, implying the possibility that Mu-CD63 plays an important role in maintaining normal renal function. Activated macrophages and splenocytes exhibited strong expression of Mu-CD63 mRNA, whereas cultured thymocytes barely expressed the mRNA irrespective of cell activation. Taken together, the present results suggest that Mu-CD63 expression is associated with differentiation and/or development of certain cell types, but not necessarily with cell proliferation.

Amino Acid Sequence↗
PubMed1994

Lectin-mediated enhancement of dengue virus infection in a mouse macrophage cell line Mk1.

Treatment of a mouse macrophage cell line Mk1 with pokeweed mitogen (PWM) either before or during but not after virus inoculation resulted in an enhancement of dengue virus (DV) infection. The infection enhancement was primarily due to an increase in the number of DV-infected cells but not to increased virus production in a cell. These results suggested that PWM treatment mediated increased DV binding and/or penetration to Mk1 cells, thereby resulting in the infection enhancement. N-acetylglucosamine (GlucNAc) did not suppress PWM-mediated enhancement of DV infection when added to Mk1 cells after PWM treatment was done, although GlucNAc clearly suppressed the effect of PWM when added simultaneously with PWM. The results implied the possibility that the PWM-mediated increase in viral binding/penetration was not due to a cross-linking by PWM between DV and a cell-surface receptor, but due to another mechanism, presumably exposure of a masked DV receptor(s). The DV receptor, unidentified as yet, involved in the PWM-mediated infection enhancement appeared to have no relation with IgG Fc receptors that are known to be involved in antibody-mediated enhancement of DV infection.

Animals↗
PubMed1994

Analysis of the core and E1 envelope region sequences of a novel variant of hepatitis C virus obtained in Indonesia.

Hepatitis C virus (HCV) is currently classified into 6 major types, HCV-1 through -6, each of which can be further divided into a few subtypes, e.g., HCV-1a, -1b, -1c, etc., on the basis of sequence variation of the viral genome. The core and E1 envelope regions of HCV genome were amplified from sera of Indonesian patients using reverse transcription-polymerase chain reaction. Sequence analysis of both core and E1 regions followed by molecular evolutionary phylogenetic analysis identified a novel sequence variant of HCV-1 (Td-6). Antibodies in the serum from which Td-6 was isolated reacted only marginally to the core protein of HCV-J, a representative strain of HCV-1b, despite strong antibody response against a mixture of the core, NS3 and NS4 proteins of HCV-1a. The possible mechanism for the diminished reactivity of the antibodies in the serum to the core protein of HCV-J is discussed.

Amino Acid Sequence↗
PubMed1994

Increased binding activity of measles virus to monkey red blood cells after long-term passage in Vero cell cultures.

Recent field isolates of measles virus (MV) obtained by using B95-8 cells have been reported not to agglutinate African green monkey red blood cells (AGM-RBC). Vero cell-adapted, plaque-forming strains derived from three field isolates at the third passage in Vero cell cultures (T8Ve-3, T11Ve-3 and N13Ve-3) also exhibited markedly decreased binding activity, as determined by infectivity-absorption and haemadsorption tests. On the other hand, binding activity of the respective strains at the twentieth passage (T8Ve-20, T11Ve-20 and N13Ve-20) increased to practically the same level as that of the Edmonston strain, a standard strain of MV passaged long-term. A membrane immunofluorescence test revealed that the decreased binding activity to AGM-RBC of T8Ve-3, T11Ve-3 and N13Ve-3 was not due to decreased expression of the haemagglutinin (H) protein on the cell surface. The deduced amino acid sequence of the H protein synthesized in T11Ve-3-infected cells was identical to that in T11Ve-20-infected cells, although a single amino acid alteration was observed when T8Ve-3 was compared with T8Ve-20. Similarly, approximately half of the N13Ve-20-infected cells synthesized an H protein identical to that produced in N13Ve-3-infected cells, and nevertheless, exhibited markedly increased haemadsorption. The present results suggest that a viral protein(s) other than the H protein contributed to the binding activity of MV to AGM-RBC.

Amino Acid Sequence↗
PubMed1994

Identification of hepatitis C virus subtype 3b (HCV-3b) among Japanese patients with liver diseases using highly efficient primers for reverse transcription-polymerase chain reaction.

With a reverse transcription-polymerase chain reaction method that utilized highly efficient primers, the NS5 region of hepatitis C virus (HCV) genome could be amplified from all of the 24 serum samples randomly obtained from Japanese patients with liver diseases. Subtype analysis on the basis of nucleotide sequence similarities of the amplified fragments revealed that 2 out of 24 Japanese patients (8.3%) were infected with the recently identified subtype HCV-3b, which had been thought to be rare in Japan.

Base Sequence↗
PubMed1994

Analysis of hepatitis C virus isolates among healthy blood donors and drug addicts in Chiang Mai, Thailand.

Hepatitis C virus (HCV) isolates obtained from 25 anti-HCV antibody-positive healthy blood donors and 29 drug addicts in Chiang Mai, Thailand, were analyzed. HCV RNA was detected in 23 blood donor samples (92%) and 24 drug addict blood samples (83%) by PCR for a portion of the NS5 region. Subtype analysis revealed that HCV type 3a (HCV-3a) was the prevailing subtype (30%), which was followed in prevalence by HCV-1a (21%), -1b (13%), -3b (13%), and -6a (2%). Six (13%) of the 47 isolates showed low sequence similarities with known types and subtypes. The sequence variants could be grouped into four branches in a molecular evolutionary phylogenetic tree.

Amino Acid Sequence↗