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T Anzai

Publications and source records attributed to T Anzai.

At least 19 recordsLinked to original sources
PubMed2006

Proline-glutamic acid-proline-lysine peptide set as a specific antigen for the serological diagnosis of strangles.

The reactivity of synthesised peptide sets for the M-like proteins SeM and SzPSe with sera from horses infected with Streptococcus equi or Streptococcus zooepidemicus, or control horses, was investigated by an ELISA. Seventeen horses were infected experimentally with S equi or S zooepidemicus, convalescent sera were obtained from 25 horses and control sera were obtained from 1945 horses. The serum antibody responses of individual horses to the peptide sets were highly variable. Some of the peptide sets for SeM reacted strongly with the sera from the horses infected experimentally with S equi, but also reacted with sera from some of the horses infected experimentally with S zooepidemicus. However, the proline-glutamic acid-proline-lysine (PEPK) repeats peptide set, synthesised from the PEPK repeats areas of SzPSe, reacted most strongly with the sera from the horses infected experimentally with S equi and the horses convalescing from strangles, and reacted only minimally with the sera from the horses infected experimentally with S zooepidemicus and the control horses.

Animals↗
PubMed2006

Novel cynomolgus macaque MHC-DPB1 polymorphisms in three South-East Asian populations.

Cynomolgus macaques (Macaca fascicularis, Mafa), alias the crab-eating monkeys or long-tailed macaques, live across a vast range of South-East Asia. These non-human primates have emerged as important animal models in infectious and chronic diseases and transplantation studies, necessitating a more extensive characterization of their major histocompatibility complex polymorphic regions. The current information on the polymorphic variation or diversity of the Mafa-DPB1 locus is largely limited in comparison with the more commonly studied rhesus macaque DPB1 locus. In this article, to better elucidate the degree and types of polymorphisms and genetic differences of Mafa-DPB1 locus among three South-East Asian populations and to investigate how the allele differences between macaques and humans might affect their respective immune responses, we identified 40 alleles within exon 2 of the Mafa-DPB1 locus by DNA sequencing using 217 individuals. We also performed evolutionary and population analyses using these sequences to reveal some population-specific alleles and trans-species allelic conservation between the cynomolgus macaques and the rhesus macaques. Of the 40 new alleles, eight belong to a newly identified lineage group not previously found in the rhesus macaque species. This allele information will be useful for medical researchers using the cynomolgus macaques in disease and immunological studies.

Alleles↗
PubMed2006

[Rapidly enlarging giant left ventricular pseudo-false aneurysm after myocardial infarction; report of a case].

A 71-year-old man was admitted to our hospital with acute myocardial infarction and cardiac tamponade. After pericardial drainage, his hemodynamics was improved. Because more than 3 days had been passed after the onset of myocardial infarction and he had severe renal dysfunction, emergent coronary angiography (CAG) was not performed. After improvement of his general status, coronary angiography and percutaneous catheter intervention was carried out, and his course was uneventful. But transthoracic echocardiography before discharge revealed a giant posterior psudoaneurysm. Patch closure and coronary artery bypass grafting was carried out under cardiopulmonary bypass, and postoperative course was uneventful. Postoperative left ventriculogram revealed disappearance of pseudoaneurysm, but relatively large akinetic area of posterior-inferior wall was left around a patch. Pseudo-false aneurysm was diagnosed by histological examination.

Aged↗
PubMed2005

ERVK9, transposons and the evolution of MHC class I duplicons within the alpha-block of the human and chimpanzee.

The genomic sequences within the alpha-block (approximately 288-310 kb) of the human and chimpanzee MHC class I region contains ten MHC class I genes and three MIC gene fragments grouped together within alternating duplicated genomic segments or duplicons. In this study, the chimpanzee and human genomic sequences were analyzed in order to determine whether the remnants of the ERVK9 and other retrotransposon sequences are useful genomic markers for reconstructing the evolutionary history of the duplicated MHC gene families within the alpha-block. A variety of genes, pseudogenes, autologous DNA transposons and retrotransposons such as Alu and ERVK9 were used to categorize the ten duplicons into four distinct structural groups. The phylogenetic relationship of the ten duplicons was examined by using the neighbour joining method to analyze transposon sequence topologies of selected Alu members, LTR16B and Charlie9. On the basis of these structural groups and the phylogeny of the duplicated transposon sequences, a duplication model was reconstructed involving four multipartite tandem duplication steps to explain the organization and evolution of the ten duplicons within the alpha-block of the chimpanzee and human. The phylogenetic analysis and inferred duplication history suggests that the Patr/HLA-F was the first MHC class I gene to have been fixed and not required as a precursor for further duplication within the alpha-block of the ancestral species.

Animals↗
PubMed2001

Autoimmunity against the second extracellular loop of beta(1)-adrenergic receptors induces beta-adrenergic receptor desensitization and myocardial hypertrophy in vivo.

Although immunoapheresis removing autoantibodies against the second extracellular domain of beta(1)-adrenergic receptors (ARs) improves cardiac function in patients with cardiomyopathy, the underlying mechanisms have not been defined. We examined the role of autoimmunity against the domain in the development of cardiac dysfunction in vivo. Japanese white rabbits were immunized with a synthetic peptide corresponding to the second extracellular loop of beta(1)-AR once a month with (beta+biso rabbits, n=10) or without (beta rabbits, n=13) bisoprolol treatment (2 mg/kg per day). Control rabbits received vehicle without bisoprolol treatment (n=13). Autoantibodies of IgG isotype against the domain were persistently detected in beta and beta+biso rabbits. Purified IgG from sera of beta and beta+biso rabbits increased cAMP production in a rabbit cardiac membrane preparation, which was blocked by bisoprolol. At 3 months, beta-AR uncoupling with increased G protein-coupled receptor kinase 5 (GRK5) expression was found in beta rabbits. At 6 months, left ventricular hypertrophy was noted with hemodynamic derangements in beta rabbits. This was accompanied by decreased beta(1)-AR density and increased inhibitory G protein and GRK5 expression, which were related to marked decrease in membrane cAMP production. These changes in beta rabbits at 6 months were prevented in beta+biso rabbits. There was no difference in the plasma norepinephrine concentration in the 3 groups over the observation period. Thus, autoimmunity against the second extracellular loop of beta(1)-ARs induced profound beta-AR desensitization and myocardial hypertrophy in vivo, associated with cardiac dysfunction. Sustained sympathomimetic-like actions of autoantibodies against the domain may be partly responsible for these changes.

Adrenergic beta-Agonists↗
PubMed2001

Isolation of virulent Rhodococcus equi from native Japanese horses.

R. equi was isolated from soil samples obtained from the environment of seven native Japanese horse breeds (Hokkaido, Kiso, Noma, Misaki, Tokara, Miyako and Yonaguni) and from fecal samples collected from three native horse breeds (Hokkaido, Kiso and Misaki). Virulent R. equi at various levels (ranging from 0.5 to 12.9%) was isolated from the feces or soil environment of Hokkaido, Kiso and Misaki horses. Isolates were investigated both for the presence of 15- to 17-kDa antigens (virulence-associated protein antigens; VapA) by colony blotting, using the monoclonal antibody 10G5, and the gene of VapA by PCR. Plasmid DNAs extracted from positive isolates were digested with restriction endonucleases, and the digestion patterns of the plasmids of virulent isolates were divided into three types. Two of the three types (87-kb type II and 90-kb type I) had already been reported in Japanese isolates, and a new type (tentatively designated as 90-kb type II) had been found in isolates from Kiso horses. Six virulent R. equi isolates from the Hokkaido horses contained an 87-kb type II plasmid. Eight of 24 isolates from the Kiso horses contained an 87-kb type II plasmid, and the remaining 16 contained a 90-kb type II (a new type) plasmid. Two isolates from the Misaki horses contained a 90-kb type I plasmid. These results demonstrate the geographic difference in the distribution of virulence plasmids in R. equi isolates among native Japanese horses.

Actinomycetales Infections↗
PubMed2001

Autoantibodies against the second extracellular loop of beta1-adrenergic receptors predict ventricular tachycardia and sudden death in patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: We sought to define the clinical and long-term prognostic implications of autoantibodies that act against the second extracellular loop of beta1-adrenergic receptors (ARs) in patients with idiopathic dilated cardiomyopathy (IDC). BACKGROUND: Although autoantibodies directed against various domains of beta-ARs are found in patients with IDC, only a subgroup against the second extracellular domain of beta1-ARs exerts intrinsic sympathomimetic-like actions on human beta-ARs. It is suggested that the autoantibodies take part in the pathophysiology of IDC and may affect long-term prognosis of patients with this disorder. METHODS: Sera from 104 patients with IDC were screened for autoantibodies that act against the second extracellular loop of beta1-ARs by enzyme-linked immunosorbent assay, using a synthetic peptide corresponding to the domain. Relations of the autoantibodies to clinical variables and long-term prognosis were assessed by multivariate analysis. RESULTS: Autoantibodies were detected in 40 patients (38%). Multifocal ventricular premature contractions (p < 0.01) and ventricular tachycardia (VT; p < 0.01) were more common in autoantibody-positive than in autoantibody-negative patients, although no differences in cardiac function or neurohormonal levels were demonstrated. The presence of autoantibodies (p = 0.001) and a low left ventricular ejection fraction (LVEF <30%; p = 0.02) were independent predictors of VT. Sudden death was independently predicted by the presence of autoantibodies (p = 0.03), as well as by LVEF <30% (p = 0.01), whereas total mortality was predicted only by LVEF <30% (p = 0.001). CONCLUSIONS: Autoantibodies directed against the second extracellular loop of beta1-ARs were closely related to serious ventricular arrhythmias in patients with IDC, and the presence of autoantibodies independently predicted sudden death. These autoantibodies may contribute to electrical instability in patients with IDC.

Adult↗
PubMed2001

Structural and phylogenetic analysis of TRAS, telomeric repeat-specific non-LTR retrotransposon families in Lepidopteran insects.

TRAS1 is a non-LTR retrotransposon inserted specifically into the telomeric repeat (TTAGG)(n) in the silkworm, Bombyx mori. To characterize the evolutionary origin of TRAS-like elements, we identified seven TRAS families (TRAS3, TRAS4, TRAS5, TRAS6, TRASY, TRASZ, and TRASW) from B. mori and four elements from two Lepidoptera, Dictyoploca japonica (TRASDJ) and Samia cynthia ricini (TRASSC3, TRASSC4, and TRASSC9). More than 2,000 copies of various Bombyx TRAS elements accumulated within (TTAGG)(n) sequences as unusual but orderly tandem repeats. The 5' and 3' regions were highly conserved within each class of Bombyx TRAS elements without truncation. This suggests that distinct classes of TRAS have been maintained independently by retrotransposition into (TTAGG)(n). The phylogenetic tree of site-specific retroelements showed that nine TRAS families in Lepidoptera constitute a single phylogenetic group that is closely related to the R1 family that inserts specifically into arthropod 28S rDNA. The higher amino acid sequence identity from endonuclease (EN) to reverse transcriptase (RT) domains between TRAS groups (about 37%-70%) than among TRAS elements and R1Bm (about 25%-30%), may reflect the presence of some DNA structure responsible for their target specificity. Sequence comparison from EN to RT domains among non-LTR elements revealed several regions conserved only within TRAS elements. We found a highly conserved region that resembles the Myb-like DNA-binding structure, between the EN and RT domains. These regions may be involved in site-specific integration of TRAS elements into the (TTAGG)(n) telomeric repeats.

Amino Acid Sequence↗
PubMed2001

Sequence-specific recognition and cleavage of telomeric repeat (TTAGG)(n) by endonuclease of non-long terminal repeat retrotransposon TRAS1.

The telomere of the silkworm Bombyx mori consists of (TTAGG/CCTAA)(n) repeats and harbors a large number of telomeric repeat-specific non-long terminal repeat retrotransposons, such as TRAS1 and SART1. To understand how these retrotransposons recognize and integrate into the telomeric repeat in a sequence-specific manner, we expressed the apurinic-apryrimidinic endonuclease-like endonuclease domain of TRAS1 (TRAS1 EN), which is supposed to digest the target DNA, and characterized its enzymatic properties. Purified TRAS1 EN could generate specific nicks on both strands of the telomeric repeat sequence between T and A of the (TTAGG)(n) strand (bottom strand) and between C and T of the (CCTAA)(n) strand (top strand). These sites are consistent with insertion sites expected from the genomic structure of boundary regions of TRAS1. Time course studies of nicking activities on both strands revealed that the cleavages on the bottom strand preceded those on the top strand, supporting the target-primed reverse transcription model. TRAS1 EN could cleave the telomeric repeats specifically even if it was flanked by longer tracts of nontelomeric sequence, indicating that the target site specificity of the TRAS1 element was mainly determined by its EN domain. Based on mutation analyses, TRAS1 EN recognizes less than 10 bp around the initial cleavage site (upstream 7 bp and downstream 3 bp), and the GTTAG sequence especially is essential for the cleavage reaction on the bottom strand (5'. TTAGGTT downward arrow AGG. 3'). TRAS1 EN, the first identified endonuclease digesting telomeric repeats, may be used as a genetic tool to shorten the telomere in insects and some other organisms.

Amino Acid Sequence↗
PubMed2001

Randomized trial of phosphodiesterase inhibitors versus catecholamines in patients with acutely decompensated heart failure.

Increased neurohormone and cytokine concentrations are associated with adverse outcome in patients with congestive heart failure, so minimizing these increases may improve outcome, even in the acute phase of decompensated heart failure. The present study was designed to test the hypothesis that phosphodiesterase inhibitors, but not catecholamines, could favorably affect neurohormone and cytokine profiles in patients with acutely decompensated heart failure. Twenty-nine patients underwent monitoring using a Swan-Ganz catheter and were randomly allocated to receive phosphodiesterase inhibitors (PDEI group, n=19) or catecholamines (CA group, n=10). Pulmonary capillary wedge pressure decreased significantly in both groups and cardiac output showed a slight, but not statistically significant increase, in both groups. There was a significant decrease in plasma brain natriuretic peptide concentration in the PDEI group, but not in the CA group, whereas plasma interleukin-6 concentration increased in the CA group, but not in the PDEI group. Phosphodiesterase inhibitors favorably affect neurohormone and cytokine concentrations in patients with acutely decompensated heart failure.

Acute Disease↗
PubMed2000

Absence of preinfarction angina is associated with a risk of no-reflow phenomenon after primary coronary angioplasty for a first anterior wall acute myocardial infarction.

BACKGROUND: No-reflow phenomenon after primary coronary angioplasty is associated with poorer left ventricular (LV) function and prognosis after acute myocardial infarction (AMI). The purpose of this study was to determine the clinical significance of preinfarction angina in the no-reflow phenomenon. METHODS AND RESULTS: A total of 40 patients with first anterior AMI were examined. All patients underwent primary balloon angioplasty or stenting within 12 h of the onset of AMI. No-reflow, defined as TIMI grade 2 flow or less without residual stenosis after angioplasty, was observed in 15 patients. Patients with no-reflow were older (67+/-9 vs. 58+/-10 years, P=0.006) and had a lower incidence of preinfarction angina (7% vs. 48%, P=0.01) than those without no-reflow. Patients with no-reflow had poorer LV function at predischarge and a higher incidence of pump failure, LV aneurysm, malignant ventricular arrhythmias or cardiac death during the hospital course in association with higher peak serum C-reactive protein levels (12.7+/-8.0 vs. 7.1+/-5.5 mg/dl, P=0.02). Multivariate analysis showed that the absence of preinfarction angina was a major independent determinant of no-reflow (RR=17.1, P=0.02). CONCLUSIONS: The absence of preinfarction angina is more frequently observed in patients with no-reflow. The beneficial effect of preinfarction angina on LV function may be explained, at least in part, by prevention of no-reflow after reperfusion.

Adult↗
PubMed2000

Pathogenicity of Rhodococcus equi expressing a virulence-associated 20 kDa protein (VapB) in foals.

Rhodococcus equi strains of intermediate virulence (IMV) for mice possess a 20kDa protein designated Virulence Associated Protein B (VapB) and a virulence plasmid of 79-100kb, and can be recovered from the submaxillary lymph nodes of pigs. The pathogenicity of such R. equi strains for foals is unknown. In this study, two foals, 42 and 43 days of age, were infected intratracheally with 10(6) and 10(9) cells of R. equi IMV strain A5, respectively. The foal infected with 10(9) cells of strain A5 became clinically ill, with the onset of illness (pyrexia and depression) occurring 21 days after inoculation. R. equi was isolated from the feces and tracheal washings of the foal from 14 to 28 days after inoculation. The foal infected with 10(6) cells of A5 showed no clinical signs, and no R. equi was isolated from any of the samples of feces or tracheal washings during the 28 days of observation. Two foals of 45 and 50 days of age were infected with 10(5) or 10(6) of virulent R. equi ATCC 33701 having 15-17kDa surface proteins designated VapA. Both exhibited severe clinical signs (pyrexia, depression and anorexia) at 12 and 13 days after inoculation. Histopathological examination revealed that strain A5 caused focal granulomatous pneumonia in the foals. R. equi IMV strain A5 was isolated from lung lesions of both foals and from the contents of the intestinal tracts of the foal infected with 10(9) bacteria. These results suggest that IMV R. equi having VapB is less virulent than virulent R. equi having VapA in foals. This finding supports our previous results on the pathogenicities of R. equi strains having these virulence-associated antigens assessed by mouse pathogenicity tests.

Animals↗
PubMed2000

Detection of DNA restriction fragment polymorphisms in Streptococcus equi.

Large-restriction-fragment (LRF) polymorphisms in Streptococcus equi (S equi subspecies equi) were studied by pulsed-field gel electrophoresis. Five or six chromosomal fragments of between 194 and 915 kb were separated by digestion with the restriction endonuclease Notl. All 20 isolates of S equi, including 12 from independent Japanese outbreaks, four from independent American outbreaks, two from a single Irish outbreak, us vaccine strain F43, and type strain NCTC 9682 were successfully typed. Seven distinctive, reproducible and stable types were identified. The 12 Japanese isolates collected between 1992 and 1998 were of LRF type II suggesting that they were derived from the same source. The remaining eight isolates were of six types. The results indicate that LRF typing should be a useful technique for investigating the source and transmission of S equi.

Animals↗
PubMed2000

Blood compatible aspects of poly(2-methoxyethylacrylate) (PMEA)--relationship between protein adsorption and platelet adhesion on PMEA surface.

Platelet adhesion and spreading is suppressed when a poly(2-methoxyethylacrylate) (PMEA) surface is used, compared with other polymer surfaces. To clarify the reason for this suppression, the relationship among the amount of the plasma protein adsorbed onto PMEA, its secondary structure and platelet adhesion was investigated. Poly(2-hydroxyethylmethacrylate) (PHEMA) and polyacrylate analogous were used as references. The amount of protein adsorbed onto PMEA was very low and similar to that absorbed onto PHEMA. Circular dichroism (CD) spectroscopy was applied to examine changes in the secondary structure of the proteins after adsorption onto the polymer surface. The conformation of the proteins adsorbed onto PHEMA changed considerably, but that of proteins adsorbed onto PMEA differed only a little from the native one. These results suggest that low platelet adhesion and spreading are closely related to the low degree of the denaturation of the protein adsorbed onto PMEA. PMEA could be developed as a promising material to produce a useful blood-contacting surface for medical devices.

Acrylates↗
PubMed2000

Presynaptic modulation of the norepinephrine-induced beta-adrenergic receptor desensitization phenomenon in vivo.

BACKGROUND: In vivo administration of norepinephrine fails to cause beta-adrenergic receptor desensitization. However, short-term exposure of cultured cells to norepinephrine induces the phenomenon in vitro. We sought to identify the local regulatory mechanisms responsible for in vivo beta-adrenergic receptor desensitization in congestive heart failure. METHODS AND RESULTS: Control rabbits received norepinephrine (n = 7) or saline (n = 7) for 1 week, and rabbits with chemical denervation induced by 6-hydroxydopamine also received norepinephrine (n = 7) or saline (n = 7). Myocardial norepinephrine content decreased 80% in both groups of denervated rabbits. beta1-Adrenergic receptor density in denervated rabbits receiving norepinephrine was lower than in those receiving saline but not in control rabbits receiving norepinephrine. Isoproterenol-competition assay revealed that there was a lower number of high-affinity binding sites with loss of guanosine triphosphate shift in denervated rabbits receiving norepinephrine. Isoproterenol-stimulated adenylyl cyclase activity in control rabbits receiving norepinephrine was lower than in those receiving saline. In denervated rabbits receiving norepinephrine, forskolin-stimulated adenylyl cyclase activity was also reduced. Immunoreactive G-protein coupled receptor kinase-2 level was increased in denervated rabbits receiving norepinephrine. CONCLUSION: There are profound alterations in beta-adrenergic receptor signaling after exposure to norepinephrine in the denervated heart. Defects in neuronal uptake may play a pivotal role in beta-adrenergic receptor desensitization in vivo.

Animals↗
PubMed2000

Methicillin-resistant coagulase-negative staphylococci isolated from healthy horses in Japan.

OBJECTIVE: To determine patterns of methicillin-resistant staphylococci isolated from apparently healthy horses. SAMPLE POPULATION: 44 horses from 8 riding clubs in Japan. PROCEDURE: Methicill in-resistant staphylococci were isolated from the skin or nares, using a selective medium containing a beta-(symboric) lactam antibiotic, ceftizoxime. Clonality of isolates was determined by use of pulsed-field gel electrophoresis. Detection of mecA, mecl, and mecR1 genes was accomplished by use of polymerase chain reactions. RESULT: Of the 44 horses, 13 (29.5%) yielded 15 isolates of methicillin-resistant staphylococci. The 15 isolates were identified as 6 species (Staphylococcus epidermidis, S lentus, S saprophyticus, S xylosus, S sciuri, and S haemolyticus). However, methicillin-resistant S aureus was seldom isolated. Each isolate contained the mecA gene and had a high resistance to beta-lactam antibiotics. Some isolates also were resistant to other antibiotics such as erythromycin and kanamycin. CONCLUSIONS AND CLINICAL RELEVANCE: Methicillin-resistant coagulase-negative staphylococci that were highly resistant to various antibiotics were isolated from apparently healthy horses in Japan. These organisms must be considered a potential threat to horses and veterinarians who care for them.

Animals↗
PubMed2000

Comparison of the phenotypes of Streptococcus zooepidemicus isolated from tonsils of healthy horses and specimens obtained from foals and donkeys with pneumonia.

OBJECTIVE: To determine whether streptococcal pneumonia is caused by strains of Streptococcus zooepidemicus similar to those obtained from the tonsils of healthy horses. SAMPLE POPULATION: 5 tonsils from healthy horses, 8 tracheal washes and 6 lung specimens from foals with pneumonia, and 5 nasopharyngeal swab specimens from donkeys with acute bronchopneumonia. PROCEDURE: Variable M-like protectively immunogenic SzP proteins of 5 isolates of S. zooepidemicus from each tonsil and clinical specimen were compared, using immunoblots. The SzP gene of 13 isolates representative of various SzP immunoblot phenotypes from 1 healthy horse and 9 horses and donkeys with pneumonia were sequenced and compared. Cell-associated hyaluronic acid concentration and resistance to phagocytosis of some isolates were measured. RESULTS: Tonsils of each healthy horse were colonized by several SzP phenotypes similar to those of foals or donkeys with pneumonia. In contrast, multiple isolates from animals with pneumonia had the same SzP phenotype, indicating infection by a single strain or clone. Analysis of the SzP sequence confirmed that differences in immunoblot phenotype were associated with sequence differences and that several SzP genotypes were in healthy horses and animals with pneumonia. Isolates with high concentrations of cell-associated hyaluronic acid were more resistant to phagocytosis. CONCLUSIONS AND CLINICAL RELEVANCE: An SzP-specific immunoblot is a useful, sensitive measure of diversity among strains of S. zooepidemicus. Single strains with SzP phenotypes similar to those found in tonsils of healthy horses cause pneumonia. Because of the diversity of SzP phenotype and genotype among isolates from animals with pneumonia, SzP phenotype is not an important determinant of invasiveness or epizootic capabilities.

Animals↗