Search PubMed⌕ Search

Biomedical subjects

Y Maeno

Publications and source records attributed to Y Maeno.

At least 91 records · Page 5Linked to original sources
PubMed2000

Expression of YAV proteins and vaccination against viral ascites among cultured juvenile yellowtail.

Yellowtail ascites virus (YAV) is a member of the family Birnaviridae and causes viral ascites among juvenile yellowtail (Seriola quinqueradiata). We have reported the cloning and expression of two viral cDNAs, the first being segment A encoding a polyprotein of viral capsid proteins (VP2 and VP3) and a protease (NS), and the second being VP2-epitope encoding serotype-specific epitope region on VP2, using a baculovirus expression system. Another viral cDNA encoding a polyprotein of NS and VP3 was cloned and expressed in this study. For the expression of NS/VP3 (YAV nt 1626 to 3066) in insect cells a 31-kDa protein, corresponding to VP3 was detected, indicating an appropriate posttranslational processing of NS/VP3 polypeptide by NS protease itself. The analysis of the N-terminal amino acid sequence of this protein showed that NS protease may cleave an Ala-Ser bond. A study of the potential for vaccination of yellowtail fry by injection of insect cell lysates infected with baculovirus, containing either cDNA of segment A, VP2-epitope, or NS/VP3 was undertaken. Only a vaccination with cell lysates infected with a recombinant virus carrying the full length of YAV segment A gene demonstrated approximately the same effect as that of inactivated YAV. This result suggested that all proteins VP2, VP3, and NS are required for an effective vaccination.

Animals↗
PubMed2000

Nuclear hypersegmentation precedes the increase in blood eosinophils in acute eosinophilic pneumonia.

In this case of acute eosinophilic pneumonia (AEP), eosinophils with hypersegmented nuclei emerged in the blood before the increase of eosinophil count. An 18-year-old woman complaining of fever, cough and dyspnea was admitted because of diffuse ground-glass opacities in her chest roentgenogram. On admission, her blood cell count revealed a marked increase of neutrophils. Although the number of eosinophils was normal, some of them contained three- or four-lobed nuclei. She was diagnosed to have AEP through bronchoalveolar lavage and transbronchial lung biopsy. The combination with acute clinical course, pulmonary infiltration and the presence of hypersegmented eosinophils in blood may imply the diagnosis of AEP.

Acute Disease↗
PubMed2000

Three-dimensional helical computed tomographic angiography in neonates and infants with complex congenital heart disease.

BACKGROUND: For the clinical management of patients with complex congenital heart disease (CHD), accurate evaluation of their morphologic conditions is critical. Three-dimensional (3D) helical computed tomography (CT) angiography has been used to assess the vascular system in adult patients; the indication for complex CHD, especially in the neonatal period, has not yet been defined. Therefore the purposes of our study were to determine the quality and limitations of current 3D helical CT angiography for neonates and infants with complex CHD and to assess the clinical utility of this technique. METHODS AND RESULTS: 3D helical CT angiography was performed in 17 patients with various types of complex CHD. Their median age was 41 days (range 3 days to 9 months), and mean body weight was 3.6 kg (range 2.2 to 8.5 kg). All 3D images were produced with the 3D reconstruction algorithm of shaded-surface display. Oral sedation was required in only 4 infants during the procedure. 3D helical CT angiography clearly demonstrated the shape and spatial relation of great arteries, proximal branch pulmonary arteries, anomalous pulmonary venous connections, the patent ductus arteriosus, and a shunt. The 3D information of extracardiac morphologic characteristics and 3D anatomic relation of each extracardiac structure were easily recognized by this imaging process. However, intracardiac structure could not be visualized because of blurred and/or unclear edges of the ventricular wall caused by respiratory movement. CONCLUSIONS: 3D helical CT angiography represents an important additional diagnostic tool and may become an alternative method to angiography or other noninvasive techniques used in the evaluation of extracardiac anomalies in neonates and infants with complex CHD.

Adult↗
PubMed2000

[PL granule-induced pneumonia requiring mechanical ventilation].

PL granule is one of the most common forms of composite medicine for colds in Japan, including acetaminophen. We report a case of PL granule-induced pneumonia that required mechanical ventilation. A 72-year old man who had been prescribed amiodarone for more than one year before for arrhythmogenic right ventricular dystrophy, repeatedly took PL granules at one-week intervals because of sneezing and fever. He then underwent acute respiratory failure. He needed mechanical ventilation for severe hypoxemia, but recovered with glucocorticoid pulse therapy. Because the blastoid transformation test using his peripheral blood lymphocytes was positive on stimulation with PL granules, but negative on amiodarone stimulation, he was diagnosed as having drug (PL granule)-induced pneumonia. Only one case of PL granule-induced pneumonia and seven of acetaminophen-induced pneumonia have been reported. None of these patients needed mechanical ventilation. PL granule-induced pneumonia should be treated cautiously because of possible acute exacerbation.

Aged↗
PubMed2000

Pulmonary nocardiosis during immunosuppressive therapy for idiopathic pulmonary fibrosis.

Nocardiosis is a subacute or chronic suppurative infection caused by Nocardia species. Although it is more common in immunocompromised hosts, idiopathic pulmonary fibrosis (IPF) has not been recognized as a predisposing factor for nocardial infection. We report a case of IPF, in which pulmonary nocardiosis developed during treatment with prednisolone and cyclophosphamide. The risk of pulmonary nocardiosis may be increased in cases of IPF on immunosuppressive therapy. Since IPF often accompanies lung carcinoma, it is important to correctly differentiate nocardiosis from carcinoma.

Aged↗
PubMed1999

Effectiveness of a vaccine against red sea bream iridoviral disease in a field trial test.

Since 1990, red sea bream iridovirus (RSIV) has caused high mortalities in the summertime in cultured red sea bream Pagrus major in southwest Japan. To establish control measures for red sea bream iridoviral disease (RSIVD), the effectiveness of a formalin-killed viral vaccine was evaluated in a field trial. Two groups each consisting of 1000 juvenile red sea bream were either intraperitoneally inoculated with vaccine (vaccinated group) or were not vaccinated (non-vaccinated group). After vaccination, the fish were held for 1 wk, then transferred to a marine net pen and observed for 12 wk. The cumulative mortalities caused by RSIVD in the vaccinated group or control group were 19.2 and 68.5%, respectively. Additionally, the presence of virus antigen in the spleen was investigated and body weight was measured 6 and 12 wk post vaccination. In the vaccinated group, viral antigen was not detected. The increase in body weight of vaccinated fish was significantly (p < 0.05) greater than that of control fish. These results suggest that the vaccine against RSIVD was effective in 1 field trial.

Animals↗
PubMed1999

Functional domains of alpha-catenin required for the strong state of cadherin-based cell adhesion.

The interaction of cadherin-catenin complex with the actin-based cytoskeleton through alpha-catenin is indispensable for cadherin-based cell adhesion activity. We reported previously that E-cadherin-alpha-catenin fusion molecules showed cell adhesion and cytoskeleton binding activities when expressed in nonepithelial L cells. Here, we constructed deletion mutants of E-cadherin-alpha-catenin fusion molecules lacking various domains of alpha-catenin and introduced them into L cells. Detailed analysis identified three distinct functional domains of alpha-catenin: a vinculin/alpha-actinin-binding domain, a ZO-1-binding domain, and an adhesion-modulation domain. Furthermore, cell dissociation assay revealed that the fusion molecules containing the ZO-1-binding domain in addition to the adhesion-modulation domain conferred the strong state of cell adhesion activity on transfectants, although those lacking the ZO-1-binding domain conferred only the weak state. The disorganization of actin-based cytoskeleton by cytochalasin D treatment shifted the cadherin-based cell adhesion from the strong to the weak state. In the epithelial cells, where alpha-catenin was not precisely colocalized with ZO-1, the ZO-1-binding domain did not completely support the strong state of cell adhesion activity. Our studies showed that the interaction of alpha-catenin with the actin-based cytoskeleton through the ZO-1-binding domain is required for the strong state of E-cadherin-based cell adhesion activity.

Animals↗
PubMed1999

alpha-catenin-deficient F9 cells differentiate into signet ring cells.

It has been demonstrated that alpha-catenin is frequently lost in diffuse type adenocarcinomas. We have isolated alpha-catenin-deficient mouse teratocarcinoma F9 cells by gene targeting. Wild-type F9 cell aggregates cultured in the presence of retinoic acid differentiated into embryoid bodies with an outer layer of epithelial cells. In contrast, cell aggregates of alpha-catenin-deficient cells did not develop outer layers under the same conditions. The outer surface cells of alpha-catenin-deficient cell aggregates, however, differentiated into epithelial cells as determined by their expression of epithelial marker proteins. These differentiated cells scattered from aggregates and showed signet ring cell morphology, which is frequently observed in diffuse type adenocarcinomas. We have provided clear evidence that a single mutation in the alpha-catenin gene may be a direct cause not only of the scattered properties of cells but also of signet ring cell formation in diffuse type adenocarcinoma.

Animals↗
PubMed1999

Progression of congenital heart disease in the prenatal period.

BACKGROUND: Prenatal echocardiography has shown evidence of prenatal development of congenital heart disease. Prenatal cardiac anatomy, chamber size and function change during gestation, so that the appearance of cardiac structure in abnormal hearts may be different from that which is usually seen postnatally. METHODS: Published prenatal echocardiographic studies were reviewed and in utero development of congenital heart disease from midtrimester to the early postnatal period is discussed. RESULTS: The growth of the great vessels and ventricles is reduced in fetuses with ventricular outflow obstruction. Valve regurgitation may progress. The foramen ovale and ductus arteriosus have been reported to become restrictive in utero in several settings. Pulmonary vascular obstructive changes may progress prenatally. Fetal arrhythmia (both bradycardia and tachycardia) may develop in utero. Development of congestive heart failure is a very important issue during follow up of fetuses with significant cardiac or extracardiac problems. Some may progress to fetal hydrops and prognosis of the affected fetuses is usually very poor. CONCLUSIONS: Correct knowledge of possible development is important for accurate prenatal diagnosis. Information on prenatal progression of the cardiac anomaly is also important to make plans for follow up and perinatal management, to predict outcomes and to counsel family. Furthermore, the benefits of prenatal treatment instead of postnatal treatment should be assessed by the accurate prediction of the progression of the cardiac problem in utero. Further extensive studies using a large number of cases is required to predict progression accurately. In addition, further studies for elucidating the mechanisms of progression is important to provide better outcomes for fetuses with various congenital heart diseases.

Arrhythmias, Cardiac↗
PubMed1999

Endothelium-specific activation of NAD(P)H oxidase in aortas of exogenously hyperinsulinemic rats.

To examine the effects of chronic hyperinsulinemia on vascular tissues, we examined the production of superoxide anion (O(-2)) in the aortic tissues of control and exogenously hyperinsulinemic rats performed by the implantation of an insulin pellet for 4 wk. O(-2) production by aortic segments from hyperinsulinemic rats was 2. 4-fold (lucigenin chemiluminescence method) and 1.7-fold (cytochrome c method) of that of control rats without any differences in O(-2) degrading activities in aortic tissues, respectively (P < 0.025). The increment was completely abolished in the presence of either 100 micromol/l apocynin (an inhibitor of NADPH oxidase) or 10 micromol/l diphenyleneiodonium (an inhibitor of flavin-containing enzyme) and was exclusively endothelium dependent. Consistently, NAD(P)H oxidase activities in endothelial homogenate in hyperinsulinemic rats were dose dependently stimulated above the values of control rats, although these activities in nonendothelial homogenate were not significantly stimulated by insulin. Furthermore, an insulin effect was also demonstrated 1 h after exposing aortic tissues to insulin. These results indicate that O(-2) production specifically increases in endothelium of aortic tissues in chronic hyperinsulinemic rats through the activation of NAD(P)H oxidase.

Animals↗
PubMed1998

The internal and external protein scaffold of the T-tubular system in cardiomyocytes.

The transverse tubule system of the cardiomyocyte remains undeformed despite the extreme forces it undergoes during the contraction-relaxation cycle, but the morphological basis for its stability remains unclear. Therefore, we have investigated the architecture and subcellular protein scaffold of the cardiac T-tubules and compared it with that of the costameres and of the free sarcolemma. Tissue samples from normal rat and monkey hearts, and left ventricular tissue from normal and cardiomyopathic human hearts obtained at transplantation surgery were investigated using immunocytochemistry and confocal microscopy and by electron microscopy. In addition, we used a re-differentiation model of isolated, cultured adult rat cardiomyocytes. The cell membrane of the cardiac T-tubules was found to contain the cell-matrix focal adhesion molecules (FAMs) vinculin, talin, the alpha5beta1 integrin and the membrane-associated proteins (MAPs) dystrophin and spectrin. FAMs and MAPs were localized in the T-tubular membrane in a similar pattern: in longitudinally oriented myocytes as transverse punctate lines at the Z-level; in transversally cut myocytes a radial tubular network was found to extend throughout the interior of the cell. Immunolabeling for basement membrane components including collagen IV, fibronectin and laminin showed a colocalization with FAMs and MAPs parallel to the transverse T-tubules. The costameres of the sarcolemma showed a protein composition resembling that of the T-tubules but the intervening segments of free sarcolemma showed absence of FAMs and presence of MAPs. For the first time, we demonstrate the existence and protein composition of the T-tubular scaffold in the human heart. Furthermore, we show that cardiomyocytes from human failing hearts have less abundant but more dilated T-tubules than do experimental animals. These results indicate that the cardiac T-tubular system contains a subcellular scaffold closely resembling that of the costameres. It consists of FAMs, MAPs and basal lamina proteins that confer structural integrity to the cardiac T-tubular membrane during contraction/relaxation cycles.

Animals↗
PubMed1998

Altered activities of transcription factors and their related gene expression in cardiac tissues of diabetic rats.

Gene regulation in the cardiovascular tissues of diabetic subjects has been reported to be altered. To examine abnormal activities in transcription factors as a possible cause of this altered gene regulation, we studied the activity of two redox-sensitive transcription factors--nuclear factor-kappaB (NF-kappaB) and activating protein-1 (AP-1)--and the change in the mRNA content of heme oxygenase-1, which is regulated by these transcription factors in the cardiac tissues of rats with streptozotocin-induced diabetes. Increased activity of NF-kappaB and AP-1 but not nuclear transcription-activating factor, as determined by an electrophoretic mobility shift assay, was found in the hearts of 4-week diabetic rats. Glycemic control by a subcutaneous injection of insulin prevented these diabetes-induced changes in transcription factor activity. In accordance with these changes, the mRNA content of heme oxygenase-1 was increased fourfold in 4-week diabetic rats and threefold in 24-week diabetic rats as compared with control rats (P < 0.01 and P < 0.05, respectively). Insulin treatment also consistently prevented changes in the mRNA content of heme oxygenase-1. The oral administration of an antioxidant, probucol, to these diabetic rats partially prevented the elevation of the activity of both NF-kappaB and AP-1, and normalized the mRNA content of heme oxygenase-1 without producing any change in the plasma glucose concentration. These results suggest that elevated oxidative stress is involved in the activation of the transcription factors NF-kappaB and AP-1 in the cardiac tissues of diabetic rats, and that these abnormal activities of transcription factors could be associated with the altered gene regulation observed in the cardiovascular tissues of diabetic rats.

Animals↗
PubMed1998

[A case of identification of two persons from heavily burned teeth by age estimation].

A man murdered his two daughters, one five years and two months old and one seven months old. He placed them into a 750 degrees C aluminum liquefying furnace. Teeth and many fragments of the severely burned bones were recovered. However, at first, the bone fragments did not offer proof that two children were put into the furnace. The age estimation of the teeth burned in liquefied aluminum was carried out based on the maturity of the teeth and the degree of absorption of deciduous teeth roots. As a result from the admixture of permanent teeth and deciduous teeth, we presumed them to be derived from more than one person.

Age Determination by Teeth↗
PubMed1998

Tenascin takes part in the progress of pathological severity in cerebral falciparum infection.

We examined plasma level of circulating form of tenascin (TC) in falciparum malaria patients, cerebral malaria and non cerebral malaria, and compared them to uninfected healthy persons. Plasma level of TC examined were significantly higher in malaria patients than in control persons (p< 0.01). The results also show that among malaria patients, TC level was higher in the cerebral malaria patients compare to non cerebral malaria patients (p<0.10). Kinetics of TC level in plasma were related to kinetics of TNF-alpha level. Moreover, patients with higher level of TC showed higher level of parasitized erythrocytes binding ratio. Immunohistochemical study showed that TC was found in the cerebral microvessels of postmortem cerebral tissues from nine cerebral malaria cases. These results provide evidence that plasma level of TC correlates with the severity in cerebral malaria patients.

Brain↗
PubMed1997

Use of high-performance liquid chromatography as an extraction procedure for analysis of triazolam in decomposed human muscle by gas chromatography-mass spectrometry.

A reliable and sensitive method for the determination of triazolam in human muscle using gas chromatography-mass spectrometry (GC-MS) is described. The drug was extracted from decomposed human muscle using three-step liquid-liquid extraction and HPLC which was performed isocratically on a conventional ODS column with a mobile phase of 0.01 M phosphate buffer (pH 6.5)-acetonitrile (7:3). Estazolam was used as an internal standard. GC-MS analysis was performed on a DB-5 capillary column. Excellent linearity was obtained over the concentration range 1-200 ng/g. The lower limit of detection was approximately 0.5 ng/g. Forensic application of the present method was also described.

Chromatography, High Pressure Liquid↗
PubMed1997

Sensitive detection of human globin chains by microbore high-performance liquid chromatography and its forensic application.

This paper describes a simple and sensitive high-performance liquid chromatographic (HPLC) method for the detection of human globin chains in blood and bloodstains. The method involves direct injection of the filtered samples of dilute hemolysates or bloodstain extracts onto a microbore C4 reversed-phase column (2.1 mm I.D.) with UV detection at 220 nm. Microbore HPLC offers a significant improvement in sensitivity with little loss of the resolution of globin chains and only small variations in the determination of gamma chain composition. The detection limit of hemoglobin (Hb) was 0.1 microgram, which is equivalent to about 1 nl of fresh whole blood. Umbilical cord blood could be differentiated from adult blood in stains that were up to twenty weeks old, by the presence of gamma globin chains. The present method will be useful for detection of abnormal Hbs and for the determination of gamma chain composition in clinical laboratories, as well as in the practice of forensic science for the analysis of minute amounts of blood and bloodstains.

Blood Stains↗