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Y Ochiai

Publications and source records attributed to Y Ochiai.

At least 37 records · Page 2Linked to original sources
PubMed1999

Conservation of putative promoter sequences located upstream of chlamydial major sigma factor gene, sigA among Chlamydia spp.

A highly conserved 40-nucleotide sequence was identified. Two completely conserved sequences, TAGATT and TAAACT, separated by 17 nucleotides resemble the consensus sequence recognized by the Escherichia coli major sigma factor and sequence found in other chlamydial promoters. In addition, the adenine-rich sequence present in many chlamydial promoters was also conserved upstream of the putative -35 element. These findings suggest that the conserved sequence may play a role in the regulatory function at the transcriptional level. Multiple ATG codons were found at the 5'-terminal region of the chlamydial sigA ORFs except for Chlamydia pneumoniae, although the putative Shine-Dargarno sequence was absent.

Bacterial Outer Membrane Proteins↗
PubMed1999

Disaccharide esters screened for inhibition of tumor necrosis factor-alpha release are new anti-cancer agents.

Tumor necrosis factor-alpha (TNF-alpha) is a proinflammatory cytokine playing a part in various pathological states. Non-toxic inhibitors of TNF-alpha release are thought to be promising agents for cancer prevention. We found that the acetone fraction of the tobacco leaf surface lipid containing glucose esters and sucrose esters inhibited both TNF-alpha release from BALB/3T3 and KATO III cells induced by okadaic acid and tumor promotion by okadaic acid on mouse skin initiated with 7,12-dimethylbenz(a)anthracene (DMBA). Next, we investigated the inhibition of TNF-alpha release with synthetic disaccharide esters, such as 6,6'-di-O-alkanoyl-alpha, alpha-trehaloses (6,6'-diester-trehaloses), 4,4'-di-O-alkanoyl-alpha, alpha-trehaloses (4,4'-diester-trehaloses) and 6,6'-diamino-6,6'-dideoxy-N,N'-dialkanoyl-alpha, alpha-trehaloses (6,6'-diamide-trehaloses) bearing fatty acids of various chain lengths, and n-dodecyl-beta-D-maltoside as a disaccharide monoester. 6,6'-Diester-trehaloses and 4,4'-diester-trehaloses of C8 to C12 fatty acids, 6,6'-diamide-trehaloses of C8 to C14 fatty acids, and n-dodecyl-beta-D-maltoside all inhibited TNF-alpha release in a dose-dependent manner. The IC50 values are 7.4-14.8 microM for 6,6'-diester-trehaloses (C8 to C12), 14.6-21.6 microM 4,4'-diester-trehaloses (C8 to C12), 2.9-15.0 microM for 6,6'-diamide-trehaloses (C8 to C14) and 23 microM for dodecyl-beta-D-maltoside. Both 6,6'-di-O-octanoyl-alpha, alpha-trehalose (C8, designated as SS555) and n-dodecyl-beta-D-maltoside (C12) inhibited tumor promotion by okadaic acid on mouse skin initiated with DMBA. Percentages of tumor-bearing mice in week 15 of tumor promotion were reduced from 60.0 to 13.3 with SS555, and to 46.7 with n-dodecyl-beta-D-maltoside. Moreover, SS555 inhibited TNF-alpha gene expression mediated through inhibition of AP-1 activation, but not NF-kappa B activation. This paper reports that diester-trehaloses of C8 to C12 fatty acids and mimics of disaccharide monoesters such as n-dodecyl-beta-D-maltoside appear to be potential cancer-preventive agents of a new type.

3T3 Cells↗
PubMed1999

Mechanistic aspects of green tea as a cancer preventive: effect of components on human stomach cancer cell lines.

It is now well accepted that (-)-epigallocatechin gallate (EGCG) inhibits carcinogenesis in the digestive tract in rodents. To understand the mechanisms of anticarcinogenesis, we first studied growth inhibition by EGCG in human stomach cancer cell lines established at Seoul National University (SNU cell lines). Inhibition by EGCG of [3H]thymidine incorporation into eight SNU cell lines was examined, in relation to transforming growth factor-beta (TGF-beta) responsiveness. Various tea polyphenols derived from green tea and black tea induced growth inhibition and apoptosis of human stomach cancer cell line KATO III, and inhibition of tumor necrosis factor-alpha (TNF-alpha) release from the cells, in the order of (-)-epicatechin gallate (ECG), EGCG, (-)-epigallocatechin (EGC), teaflavins (TF) and (-)-epicatechin (EC). In addition, we demonstrated that EGCG inhibited TNF-alpha gene expression in KATO III cells, as well as okadaic acid-induced AP-1 and NF-kappa B activation. The inhibitory potencies of EGCG for AP-1 and NF-kappa B binding to DNA were different between KATO III cells and mouse fibroblast cell line BALB/3T3. Thus, EGCG and other tea polyphenols may interact with various transcription factors, in addition to AP-1 and NF-kappa B, in nuclei of various cells, resulting in inhibition of TNF-alpha gene expression and TNF-alpha release.

3T3 Cells↗
PubMed1998

Two types of mRNA encoding myosin regulatory light chain in carp fast skeletal muscle differ in their 3' non-coding regions and expression patterns following temperature acclimation.

cDNA clones encoding the myosin regulatory light chain (RLC) were isolated from a cDNA library prepared from fast skeletal muscle of the carp Cyprinus carpio L. Two types of cDNA clone encoding carp RLC were found with identical deduced amino acid sequences. The two mRNAs differed in the number of polyadenylation signals prior to the poly(A) tail in the 3' non-coding region. The two mRNA species, with approximate sizes of 1.4 and 0.8 kilobases, were also observed in northern blot analysis. Carp were acclimated for a minimum of 5 weeks to either 10 degreesC or 30 degreesC (14 h:10 h light:dark photoperiod). The total levels of mRNA transcripts coding for the RLC and myosin heavy chain were, respectively, 3.3 and 3.9 times higher in cold- than in warm-acclimated fish. Differences in the levels of RLC in mRNA transcripts were largely due to the concentration of the 1.4 kilobase mRNA species.

Journal Article↗
PubMed1998

Effects of amrinone, a phosphodiesterase inhibitor, on right ventricular/arterial coupling immediately after cardiac operations.

OBJECTIVE: Amrinone, a selective phosphodiesterase III inhibitor, is reported to have a potent inotropic effect on the left ventricle, but the effects of this drug on right ventricular contractility in the clinical setting are unknown. The concept of ventricular/arterial coupling was applied to investigate the effects of amrinone on right ventricular contractility and afterload with transesophageal echocardiography. METHODS AND RESULTS: The study was performed in the intensive care unit with 11 patients who had undergone cardiac operations. Right ventricular cross-sectional area was measured with transesophageal echocardiography equipped with a capability of automated border detection as a surrogate for right ventricular volume. Multiple pressure-area loops were obtained by reducing preload to measure end-systolic elastance and effective arterial elastance. External work and pressure-volume area were also measured to calculate the efficiency of energy transfer from pressure-volume area to external work. Nitroprusside (0.3 to 0.5 microg x kg(-1) x min(-1)) and amrinone (1 mg x kg(-1) intravenously followed by 10 microg x kg(-1) x min(-1)) were administered. With nitroprusside infusion, end-systolic elastance and effective arterial elastance remained unchanged (end-systolic elastance, 4.73 +/- 2.18 mm Hg/cm2 to 4.65 +/- 2.09 mm Hg/cm2; effective arterial elastance, 8.05 +/- 3.84 mm Hg/cm2 to 7.70 +/- 3.64 mm Hg/cm2). In contrast, amrinone reduced afterload (effective arterial elastance, 8.82 +/- 3.99 mm Hg/cm2 to 7.05 +/- 4.01 mm Hg/cm2, p = 0.004) and enhanced contractility (end-systolic elastance, 4.47 +/- 1.79 mm Hg/cm2 to 6.56 +/- 2.22 mm Hg/cm2, p = 0.007). Consequently, amrinone decreased the ventricular/arterial coupling ratio (effective arterial elastance/end-systolic elastance, 2.40 +/- 1.45 to 1.16 +/- 0.63, p = 0.009) and improved the efficiency of energy transfer (external work/pressure-volume area, 0.44 +/- 0.15 to 0.54 +/- 0.15, p = 0.013). CONCLUSIONS: Right ventricular pressure-area relations obtained with transesophageal echocardiography could successfully separate the simultaneous change in right ventricular systolic mechanics and afterload caused by amrinone. Amrinone caused enhancement of right ventricular contractility and afterload reduction.

Adult↗
PubMed1998

In vitro susceptibility of Chlamydia pecorum to macrolides, tetracyclines, quinolones and beta-lactam.

The in vitro susceptibility of Chlamydia pecorum to two macrolides (clarithromycin and erythromycin), two tetracyclines (doxycycline and minocycline), two quinolones (ofloxacin and ciprofloxacin) and one beta-lactam (ampicillin) was determined. The MICs were 0.004 to 0.008 microg/ml for clarithromycin, 0.008 to 0.031 microg/ml for doxycycline and minocycline, 0.063 to 0.125 microg/ml for erythromycin, 0.25 to 0.5 microg/ml for ofloxacin and 0.25 to 1.0 microg/ml for ciprofloxacin. The MIC for ampicillin was greater than 1,024 microg/ml. The results show clarithromycin and doxycycline are the two most effective drugs against C. pecorum.

Animals↗
PubMed1998

Recovery from complete atrioventricular block caused by idiopathic giant cell myocarditis after corticosteroid therapy.

Giant cell myocarditis (GCM) is a rapidly progressive disease that leads to ventricular tachycardia or high-grade atrioventricular (A-V) block, frequently requiring a pacemaker. A 64-year-old woman developed syncope as a result of idiopathic GCM with A-V block. She required both a temporary and a permanent pacemaker. Two-dimensional echocardiography showed severely reduced wall motion. There was no histologic or clinical evidence to suggest sarcoidosis. Despite treatment with diuretics and an angiotensin-converting enzyme inhibitor, exertional dyspnea persisted. She received prednisolone 4 months after the onset of complete A-V block in the late phase of GCM. Prednisolone improved A-V nodal conduction in spite of the fact that there was no influence from LV wall motion, and sinus rhythm has continued for more than 2 years. In this patient, prednisolone was effective in the treatment of GCM.

Anti-Inflammatory Agents↗
PubMed1998

Two types of mRNA encoding myosin regulatory light chain in carp fast skeletal muscle differ in their 3' non-coding regions and expression patterns following temperature acclimation.

cDNA clones encoding the myosin regulatory light chain (RLC) were isolated from a cDNA library prepared from fast skeletal muscle of the carp Cyprinus carpio L. Two types of cDNA clone encoding carp RLC were found with identical deduced amino acid sequences. The two mRNAs differed in the number of polyadenylation signals prior to the poly(A) tail in the 3' non-coding region. The two mRNA species, with approximate sizes of 1.4 and 0.8 kilobases, were also observed in northern blot analysis. Carp were acclimated for a minimum of 5 weeks to either 10 degrees C or 30 degrees C (14h:10h light:dark photoperiod). The total levels of mRNA transcripts coding for the RLC and myosin heavy chain were, respectively, 3.3 and 3.9 times higher in cold-than in warm-acclimated fish. Differences in the levels of RLC in mRNA transcripts were largely due to the concentration of the 1.4 kilobase mRNA species.

Adaptation, Physiological↗
PubMed1997

Gazelle herpesvirus 1: a new neurotropic herpesvirus immunologically related to equine herpesvirus 1.

A herpesvirus was isolated from Thomson's gazelle (Gazella thomsoni) kept at a zoological garden in Japan during an outbreak of epizootic acute encephalitis. The virus, gazelle herpesvirus 1 (GHV-1), was serologically related to equine herpesvirus 1 (EHV-1). However, DNA fingerprints of GHV-1 were different from those of EHV-1 and other equine herpesviruses. Southern hybridization with probes of cloned BamHI fragments derived from UL and US segments of EHV-1 revealed differences in the DNA restriction profiles throughout the entire genome. Nucleotide sequences were determined for a conserved region of an essential envelope glycoprotein B (gB) gene and a type-specific glycoprotein G (gG) homologue gene. The predicted amino acid sequence of GHV-1 gB showed 97, 92, 61, and 57% identity to EHV-1, EHV-4, feline herpesvirus, and pseudorabies virus, respectively, indicating that GHV-1 was closer to EHV-1 than any other herpesvirus. The GHV-1 gG gene showed 93.2, 92.3, and 53% identity to EHV-1, EHV-8, and EHV-4 gGs, respectively. GHV-1 was virulent to suckling mice of the ICR strain by intracerebral inoculation and was virulent to 4-week-old BALB/c mice by intranasal inoculation, causing neurological symptoms and death. We conclude that GHV-1 is a new type of equine herpesvirus with strong neurotropism.

Amino Acid Sequence↗
PubMed1997

Diversity of feline Chlamydia psittaci revealed by random amplification of polymorphic DNA.

DNA samples from C. psittaci including 6 strains of feline origin, 10 strains of avian origin, 1 strain of ovine origin and 1 strain of guinea pig origin were amplified each with three 10-nucleotide (nt) primers and four > 18-nt primers. Amplified products were separated by polyacrylamide gel electrophoresis. Eight patterns were recognized by random amplification of polymorphic DNA (RAPD) fingerprinting of C. psittaci: 2 patterns of feline origin, 5 patterns of avian origin and 1 pattern of guinea pig origin. DNA of feline or guinea pig origin was clearly distinguished from the other strains of C. psittaci by RAPD analysis, as shown by the absence of any common fragments in electrophoresis. The RAPD analysis indicated at least 2 types of feline C. psittaci. The RAPD typing is suggested as a convenient tool for molecular epidemiology of chlamydial infection.

Animals↗
PubMed1997

Phylogenetic analysis of the genus Chlamydia based on 16S rRNA gene sequences.

The phylogenetic relationships among Chlamydia spp. were investigated by comparing 16S rRNA gene sequences. In this analysis we used 14 strains of Chlamydia psittaci, including seven feline isolates, two avian isolates, two human isolates, one bovine isolates, one ovine isolate, and one koala isolate; and nine strains of Chlamydia trachomatis, including six human isolates, two swine isolates, and one mouse isolate. A phylogenetic analysis of the 16S rRNA gene sequences of these organisms and seven previously published sequences revealed eight genetic groups which formed two clusters. The first cluster was composed of C. pecorum, Chlamydia pneumoniae, and C. psittaci and included three genetic groups (one group containing avian, human, and ovine strains, one group containing feline strains, and one group containing guinea pig strains). The second cluster was composed of C. trachomatis and also included three genetic groups (one group containing human strains, one group containing swine isolates, and one group containing rodent strains). The strains in each genetic group exhibited similar genetic distances. The results of the phylogenetic analysis agreed with the results of previous genomic DNA, ompA gene allele, and biotyping studies. Therefore, the genetic groups based on genetic distances may be considered a criterion for species identification.

Animals↗
PubMed1996

Clinical evaluation of serum amlodipine level in patients with angina pectoris.

Serum amlodipine levels were determined in 18 patients with vasospastic angina. Patients were divided into two groups: Group A (n = 9) received amlodipine 5 mg by single daily administration, and Group B (n = 9) received 10 mg given by single daily administration for the first 3 days, then 5 mg from the 4th day on. The serum amlodipine concentration in Group A took 7 days to reach a steady state of around 8 ng/ml. The level in Group B was 8.9 ng/ml at 3 days. From these results, the optimal dosage of amlodipine in the treatment of angina pectoris is 10 mg for the initial 3 days followed by 5 mg thereafter.

Aged↗
PubMed1996

Inhibition of lipid peroxidation with the lazaroid U74500A attenuates ischemia-reperfusion injury in a canine orthotopic heart transplantation model.

BACKGROUND: The lazaroid U74500A is a 21-aminosteroid that inhibits lipid peroxidation and attenuates ischemia-reperfusion injury. We examined the effect of U74500A on heart preservation with the use of a clinically relevant canine orthotopic heart transplantation model. METHODS AND RESULTS: Six donor dogs (group L) were pretreated intravenously with U74500A (10 mg/kg), and the dogs without pretreatment served as a control (group C, n = 6). The donor heart was preserved in cold University of Wisconsin solution for 24 hours. The heart was then transplanted orthotopically. Myocardial biopsy was performed to measure the adenosine triphosphate level at the end of ischemia. Before reperfusion, recipients in group L received another dose of U74500A (10 mg/kg) intravenously. After 3 hours of reperfusion, left ventricular function was evaluated by left ventricular pressure-volume relations with the use of a Millar catheter and conductance catheter, thereby deriving the slope of the end-systolic pressure-volume relation, the slope of the stroke work-- end-diastolic volume relation, and the slope of the maximum dP/dt--end-diastolic volume relation. At the same time, serum creatine kinase MB isoenzyme and lipid peroxide levels were measured. The slopes of the end-systolic pressure-volume relation, the stroke work--end-diastolic volume relation, and the maximum dP/dt--end-diastolic volume relation for group L were significantly higher than those for group C. The adenosine triphosphate levels for group L were significantly higher than those for group C. Serum creatine kinase MB isoenzyme and lipid peroxide levels for group L were significantly lower than those for group C. CONCLUSIONS: Inhibition of lipid peroxidation by the administration of U74500A was effective for 24-hour canine cardiac preservation. These results indicate that U74500A is a promising agent for heart allograft preservation.

Adenosine Triphosphate↗
PubMed1996

Seroepidemiology of feline chlamydiosis by microimmunofluorescence assay with multiple strains as antigens.

The prevalence of anti-chlamydia antibodies was examined in 232 cat sera collected in 1985 and from 1993 to 1995 from laboratories and veterinary hospitals located in 11 prefectures of Japan. The antibodies were determined by an indirect microimmunofluorescence test using six strains of feline Chlamydia: one strain each of avian- and guinea pig-derived C. psittaci and one strain each of C.pecorum, C.pneumoniae and C.trachomatis. Positive rates of IgG antibodies to chlamydiae were 34.4% in 1985 and 16.5-21.4% from 1993 to 1995. Positive rates of IgM antibodies to chlamydiae were 8.2% in 1985 and 6.6-14.3% from 1993 to 1995. Variations in antibody reactivity to the different feline strains were observed. The results suggest the wide prevalence of chlamydial infection in cats in Japan, and antigenic diversity in the feline strains of C.psittaci.

Animals↗
PubMed1996

Successful twenty-four-hour canine lung preservation with lazaroid U74500A.

BACKGROUND: Lipid peroxidation is known to contribute to ischemia-reperfusion injury. U74500A is a 21-aminosteroid (lazaroid) that prevents lipid peroxidation without corticoid side effects. We examined the effect of U74500A on lung preservation using a canine orthotopic single left lung transplantation model. METHODS: Twelve adult mongrel dogs underwent left lung allotransplantation. The lungs of the donor dogs were flushed with University of Wisconsin solution (50 ml/kg). Six donor dogs were pretreated with U74500A (5 mg/kg intravenously) before preservation (group L, n = 6), whereas those dogs without pretreatment served as controls (group C, n = 6). Allografts were stored in University of Wisconsin solution for 24 hours at 1 degrees C. Left single lung transplantations were performed by means of standard technique. Before reperfusion, recipients in group L received another dose of U74500A. Arterial blood gas analysis and hemodynamic measurements were made by occluding the right pulmonary artery to evaluate the transplanted left lung function at a inspired oxygen fraction of 1.0. Serum lipid peroxide level was measured after 2 hours of reperfusion. RESULTS: Arterial oxygen tension, arterial carbon dioxide tension, and left pulmonary vascular resistance at 6 hours after reperfusion were significantly better in group L than in group C (arterial oxygen tension: 510 +/- 66 and 219 +/- 149 mm Hg; arterial carbon dioxide tension: 47 +/- 16 and 68 +/- 14 mm Hg; left pulmonary vascular resistance: 2412 +/- 826 and 3904 +/- 1251 dyn center dot sec/cm5, group L and group C, respectively). Serum lipid peroxide level was significantly lower in group L (0.25 +/- 0.24 nmol/ml) than in group C (0.92 +/- 0.53). CONCLUSIONS: The administration of U74500A prevented lipid peroxidation and preserved pulmonary allograft function after 24 hours of ischemia.

Animals↗