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T Takasaki

Publications and source records attributed to T Takasaki.

At least 37 records · Page 2Linked to original sources
PubMed2000

Highly divergent sequences of the pollen self-incompatibility (S) gene in class-I S haplotypes of Brassica campestris (syn. rapa) L.

Self-incompatibility (SI) enables flowering plants to discriminate between self- and non-self-pollen. In Brassica, SI is controlled by the highly polymorphic S locus. The recently identified male determinant, termed SP11 or SCR, is thought to be the ligand of S receptor kinase, the female determinant. To examine functional and evolutionary properties of SP11, we cloned 14 alleles from class-I S haplotypes of Brassica campestris and carried out sequence analyses. The sequences of mature SP11 proteins are highly divergent, except for the presence of conserved cysteines. The phylogenetic trees suggest possible co-evolution of the genes encoding the male and female determinants.

Alleles↗
PubMed2000

The S receptor kinase determines self-incompatibility in Brassica stigma.

The self-incompatibility possessed by Brassica is an intraspecific reproductive barrier by which the stigma rejects self-pollen but accepts non-self-pollen for fertilization. The molecular/biochemical bases of recognition and rejection have been intensively studied. Self-incompatibility in Brassica is sporophytically controlled by the polymorphic S locus. Two tightly linked polymorphic genes at the S locus, S receptor kinase gene (SRK) and S locus glycoprotein gene (SLG), are specifically expressed in the papillar cells of the stigma, and analyses of self-compatible lines of Brassica have suggested that together they control stigma function in self-incompatibility interactions. Here we show, by transforming self-incompatible plants of Brassica rapa with an SRK28 and an SLG28 transgene separately, that expression of SRK28 alone, but not SLG28 alone, conferred the ability to reject self (S28)-pollen on the transgenic plants. We also show that the ability of SRK28 to reject S28 pollen was enhanced by SLG28. We conclude that SRK alone determines S haplotype specificity of the stigma, and that SLG acts to promote a full manifestation of the self-incompatibility response.

Brassica↗
PubMed2000

A malignant rhabdoid tumor of the kidney occurring concurrently with a brain tumor: report of a case.

Malignant rhabdoid tumor of the kidney (MRTK) is one of the most lethal neoplasms to occur in young infants. Cases of MRTK accompanying an embryonal tumor in the central nervous system have occasionally been described. We present herein an interesting case of MRTK that was clinically diagnosed preoperatively. A male infant aged 6 months with both a midline brain tumor and a renal neoplasm was transferred to our institution. Although roentgenographic evaluation suggested that the renal lesion was a Wilms' tumor, midkine (MK), a growth and differentiation factor characteristically present in the urine of patients with Wilms' tumor, was not detected. A preoperative diagnosis of MRTK was established based on the lack of urinary MK in addition to the typical clinical features of the young age and the concurrent brain tumor.

Brain Neoplasms↗
PubMed2000

T-cell activation and induction of antibodies and memory T cells by immunization with inactivated Japanese encephalitis vaccine.

Mouse brain-derived inactivated Japanese encephalitis (JE) vaccine is the only currently internationally accepted vaccine against JE virus. We analyzed cellular and humoral immune responses to the JE vaccine in healthy adults in order to understand the protective immunity induced by this vaccine. Immunization with the JE vaccine induced T-cell activation in vivo, demonstrated by increase in the plasma levels of interleukin (IL)-2 and soluble CD8. JE virus-specific antibodies determined in radioimmunoprecipitation (RIP), hemagglutination inhibition (HI), and neutralization assays were also induced by immunization with the JE vaccine. JE virus-specific memory T cells were detected 60 days after immunization. These results suggest that protective immunity induced by the inactivated JE vaccine includes JE virus-specific T cells as well as antibodies with multiple biological activities.

Adult↗
PubMed2000

Serotype-cross-reactive immunoglobulin M responses in dengue virus infections determined by enzyme-linked immunosorbent assay.

We developed immunoglobulin M (IgM) antibody capture enzyme-linked immunosorbent assays (ELISAs) with four monovalent dengue virus antigens. We attempted to determine whether IgM responses in dengue virus infections are serotype specific or serotype cross-reactive. Serum samples from 14 confirmed dengue cases were examined. In these 14 cases, which consisted of 12 Japanese and 2 non-Japanese patients, infecting dengue virus serotypes were defined by reverse transcription-PCR. Thirteen of the 14 cases were IgM positive in ELISA. IgM responses were serotype cross-reactive in these 13 cases but were highest against infecting dengue virus serotype in 9 of the 13 cases. These results indicate that IgM responses are generally dengue serotype cross-reactive but that IgM levels are highest against the infecting serotype in most dengue cases.

Aedes↗
PubMed2000

Percutaneous cardiopulmonary support as a bridge to emergency operation--two surviving cases.

Two patients had percutaneous cardiopulmonary support (PCPS) used as a bridge to emergency surgery. A 66-year-old man admitted with profound cardiogenic shock underwent direct stenting under PCPS with the diagnosis of acute myocardial infarction of the left main trunk, with the intention of performing revascularization as soon as possible. Subsequently, double coronary artery bypass grafting was successfully accomplished. A 69-year-old woman, admitted with acute heart failure due to critical aortic stenosis, manifested cardiogenic shock while undergoing catheterization. PCPS was immediately instituted until the acute deterioration of her hemodynamic state could be reversed, and was continued uneventfully till aortic valve replacement was performed. These results suggest that the current PCPS system is an effective response to acute circulatory collapse and will contributed to the improved survival of patients.

Aged↗
PubMed1999

Introduction of SLG (S locus glycoprotein) alters the phenotype of endogenous S haplotype, but confers no new S haplotype specificity in Brassica rapa L.

Self-incompatibility (SI) in Brassicaceae is genetically controlled by the S locus complex in which S locus glycoprotein (SLG) and S receptor kinase (SRK) genes have been identified, and these two genes encoding stigma proteins are believed to play important roles in SI recognition reaction. Here we introduced the SLG43 gene of Brassica rapa into a self-incompatible cultivar, Osome, of B. rapa, and examined the effect of this transgene on the SI behavior of the transgenic plants. Preliminary pollination experiments demonstrated that Osome carried S52 and S60, and both were codominant in stigma, but S52 was dominant to S60 in pollen. S43 was found to be recessive to S52 and codominant with S60 in stigma. The nucleotide sequence of SLG43 was more similar to that of SLG52 (87.8% identity) than to that of SLG60 (74.8% identity). Three of the ten primary transformants (designated No. 1 to No. 10) were either completely (No. 9) or partially (No. 6 and No. 7) self-compatible; the SI phenotype of the stigma was changed from S52S60 to S60, but the SI phenotype of the pollen was not altered. In these three plants, the mRNA and protein levels of both SLG43 and SLG52 were reduced, whereas those of SLG60 were not. All the plants in the selfed progeny of No. 9 and No. 6 regained SI and they produced a normal level of SLG52. These results suggest that the alteration of the SI phenotype of the stigma in the transformants Nos. 6, 7, and 9 was the result of specific co-suppression between the SLG43 transgene and the endogenous SLG52 gene. Three of the transformants (Nos. 5, 8 and 10) produced SLG43 protein, but their SI phenotype was not altered. The S60 homozygotes in the selfed progeny of No. 10 which produced the highest level of SLG43 were studied because S43 was codominant with S60 in the stigma. They produced SLG43 at approximately the same level as did S43S60 heterozygotes, but did not show S43 haplotype specificity at the stigma side. We conclude that SLG is necessary for the expression of the S haplotype specificity in the stigma but the introduction of SLG alone is not sufficient for conferring a novel S haplotype specificity to the stigma.

Blotting, Southern↗
PubMed1999

Obesity affects expression of progesterone receptors and node metastasis of mammary carcinomas in postmenopausal women without a family history.

Possible relationships between risk factors, such as obesity and a family history of breast cancer, and prognostic factors of mammary carcinomas were investigated by examining the body mass index of patients and the expression of estrogen (ER) and progesterone receptors (PgR), c-erbB-2 and p53, grade of histology, size of tumors and nodal status of mammary carcinomas. There was no significant difference in the body mass index of premenopausal patients either with or without a family history. For postmenopausal patients, the body mass index was significantly low in patients with a family history compared with patients without a family history. In premenopausal patients with or without a family history and in postmenopausal patients with a family history, there was no significant difference in the body mass index regardless of the mammary carcinoma prognostic factor, such as expression of ER, PgR, c-erbB-2 and p53, grade of histology, size of tumors and nodal status. However, in postmenopausal patients without a family history, body mass index was significantly high for patients with mammary carcinomas that had PgR expression and node metastasis. These results suggest that obesity may affect the PgR status and nodal status of mammary carcinomas in postmenopausal patients without a family history.

Body Mass Index↗
PubMed1999

Fine structure and morphogenesis of Borna disease virus.

Borna disease virus (BDV), a negative nonsegmented single-stranded RNA virus, has not been fully characterized morphologically. Here we present what is to our knowledge the first data on the fine ultrastructure and morphogenesis of BDV. The supernatant of MDCK cells persistently infected with BDV treated with n-butyrate contained many virus-like particles and more BDV-specific RNA than that of untreated samples. The particles were spherical, enveloped, and approximately 130 nm in diameter; had spikes 7 nm in length; and reacted with BDV p40 antibody. A thin nucleocapsid, 4 nm in width, was present peripherally in contrast to the thick nucleocapsid of hemagglutinating virus of Japan. The BDV particles reproduced by budding on the cell surface.

Animals↗
PubMed1999

Laboratory diagnosis of dengue virus infection by reverse transcriptase polymerase chain reaction (RT-PCR) and IgM-capture enzyme-linked immunosorbent assay (ELISA).

Dengue virus infections are a major public health problem in most tropical and sub-tropical countries of the world. Dengue is occasionally imported by travelers who visit tropical areas and become infected with dengue virus. Laboratory diagnosis is essential for confirming the diagnosis of this virus. For purposes of confirmation, detection of specific IgM by IgM-capture enzyme-linked immunosorbent assay (ELISA) and of dengue virus genome by reverse transcriptase polymerase chain reaction (RT-PCR) have recently been used. In the present study, we tested serum specimens from dengue-suspected Japanese cases, by IgM-capture ELISA, RT-PCR, HI, and virus isolation. Serum samples collected before or on the day of defervescence were positive by RT-PCR, though no PCR-positive samples were obtained after fever day 1. IgM-capture ELISA was positive as early as disease day 4, and all samples but one were IgM-positive when collected on disease day 5 or later. In light of these findings, we recommend that both RT-PCR and IgM-capture ELISA be performed, irrespective of the stage of dengue illness. Combination of RT-PCR and IgM-capture ELISA increases the ability to diagnose dengue virus infection, even in the only that a single serum specimen from the patient is available.

Dengue↗
PubMed1998

Serum antibodies to human herpesvirus 7, human herpesvirus 6 and cytomegalovirus in patients with idiopathic facial nerve palsy or sudden deafness.

The aetiology of idiopathic facial nerve palsy (Bell's palsy) and sudden deafness are not known, although viruses have been suspected as a cause of them. We investigated the relationship between Bell's palsy or sudden deafness, and reactivation of cytomegalovirus, human herpesvirus 6 (HHV-6) and 7 (HHV-7). Paired sera were collected from 22 patients with Bell's palsy and 24 patients with sudden deafness. IgG antibody titres to HHV-7 were increased in one patient with Bell's palsy. IgG antibody titres to HHV-6 were increased in one patient with Bell's palsy and two with sudden deafness. IgG antibody titres to cytomegalovirus were increased in one patient with sudden deafness. Titres of the three viral antibodies were not increased simultaneously in any patients. These viruses may contribute to the development of Bell's palsy or sudden deafness in some cases. It is, however, unlikely that these viruses are the main cause of Bell's palsy and sudden deafness in the majority of patients.

Adolescent↗
PubMed1998

Molecular characterization of S locus genes, SLG and SRK, in a pollen-recessive self-incompatibility haplotype of Brassica rapa L.

In Brassica species that exhibit self-incompatibility, two genes, SLG and SRK, at the S locus are involved in the recognition reaction with self and non-self pollen. From a pollen-recessive S29 haplotype of Brassica rapa, both cDNA and genomic DNA clones for these two genes were isolated and characterized. The nucleotide sequence for the S domain of SRK29 showed a high degree of similarity with that of SLG29, and they belong to Class II type. RNA gel blot analysis showed that the transcript of SLG29 consisted of the first and second exons, and no other transcript containing any part of the intron sequence was detected. Because no transmembrane domain was encoded by the second exon of SLG29, SLG29 was designated a secreted type glycoprotein. SLGs of two other pollen-recessive haplotypes, S40 and S44, of B. rapa also had a similar structure to that of SLG29. Previously, SLG2 from a pollen-recessive haplotype, S2, of Brassica oleracea was found to produce two different transcripts, one for the secreted type glycoprotein and the other for a putative membrane-anchored form of SLG. Therefore, the nature of these SLGs from pollen-recessive haplotypes of B. rapa is different from that of SLG2 of B. oleracea.

Amino Acid Sequence↗
PubMed1998

Histological and biological characteristics of microinvasion in mammary carcinomas < or = 2 cm in diameter.

Fifty-two mammary carcinomas, 2 cm or less in diameter, were examined in order to clarify the morphology and biology of microinvasion. The morphological characteristics of microinvasion of carcinomas include: (i) a loss of myoepithelial cells and a rupture with concomitant loss of collagen IV and laminin in the basement membrane of involved mammary glands; and (ii) budding of carcinomas from the rupture into the stroma. When microinvasion was defined as a rupture of < 200 microm in the basement membrane with invasion, the number of microinvasions per 1 mm of basement membrane was larger in the tumors in which the area of invasion was larger. The prevalence of microinvasion showed a significant correlation with lymph node metastasis and the rate of histological deviation, while no correlation of expression of either estrogen receptors or progesterone receptors and c-erbB-2 protein was found. The study clarified that the early invasion of mammary carcinomas could be detected by the immunohistochemical method using anti-smooth muscle actin, laminin and collagen IV antibodies. The study also suggested that microinvasion might be an indicator of lymph node metastasis in mammary carcinomas < or = 2 cm diameter.

Adenocarcinoma, Papillary↗
PubMed1998

The expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor is correlated to angiogenesis in breast cancer.

It has been shown that human thymidine phosphorylase (TP) is identical to platelet-derived endothelial cell growth factor and has angiogenic activity. In the present study, the expression of TP was examined in 139 mammary carcinomas and 35 benign mammary disorders using biochemical and immunohistochemical methods. Moreover, in order to evaluate the significance of TP expression in mammary carcinomas, the relationship between vascular density and various clinicopathological factors, including age and menopausal status of patients with a mammary carcinoma, were compared with the size, nodal status, expression of estrogen receptor (ER), progesterone receptor (PgR), c-erbB-2, p53 and TP of a mammary carcinoma. Thymidine phosphorylase expression increased in both the nuclei and cytoplasm of mammary carcinoma cells in comparison to mammary benign disorder cells. The number of microvessels in mammary carcinomas was generally correlated to the number of tumor cells with TP expression in cytoplasm. The number of cells with TP expression in cytoplasm was significantly large in tumors that measured 3-4 cm in diameter, compared with tumors measuring 1-2 and 5-6 cm in diameter. In mammary tumors of 1-4 cm diameter, TP expression and vessel density were significantly high in tumors negative for ER or positive for c-erbB2 and in tumors positive for TP or c-erbB2, respectively; whereas tumors of 5-6 cm in diameter were not modified by any clinicopathological factors. The results indicated that TP plays an important angiogenetic role in mammary carcinomas, especially tumors with a certain progression.

Adult↗
PubMed1998

Immunohistochemical studies on expression of human vascular smooth muscle myosin heavy chain isoforms in normal mammary glands, benign mammary disorders and mammary carcinomas.

The expression of myosin in normal and diseased mammary glands of 199 Japanese women was evaluated immunohistochemically by the avidin-biotin peroxidase complex method using antibodies to three human smooth muscle myosin heavy chain isoforms derived from the vascular smooth muscle: myosin SM1 is expressed consistently from fetal stage to adulthood, myosin SM2 appears only in well-differentiated smooth muscle after birth, and myosin SMemb is more abundant in embryonic aortas. SM1 was expressed in myoepithelial cells of normal mammary glands and fibrocystic diseases and in myoepithelial-like tumor cells in the basal layer of fibroadenomas and phyllodes tumors. SM2 was expressed only in the myoepithelial cells of mammary glands in breastfeeding women. SMemb was expressed more intensely in the cytoplasm of luminal epithelial cells in larger fibroadenomas (P< 0.01), or in the cytoplasm of carcinoma cells in invasive ductal carcinomas with metastasized lymph nodes (P< 0.001) and in those of higher histological grade (P<0.0001). Multivariate logistic analysis showed a significant correlation only between the expression of SMemb and histological grade (P< 0.0001), which is a prognostic factor of mammary carcinomas. These findings suggested the possible prognostic value of SMemb.

Adolescent↗
PubMed1998

[Studies for dynamics of reverse transcriptase inhibiting antibody in sera from HIV-1 infected individuals].

Antibodies inhibiting human immunodeficiency virus type 1 (HIV-1) reverse transcriptase activity (RTI-antibody), Binding inhibition antibody (BI-antibody) and polymerization inhibition antibody (PI-antibody) were investigated for their ability to inhibiting RT activity in 248 HIV-1 infected individuals and 99 healthy individuals. In BI-antibody, high titer samples were determined more in than in RTI- and PI-antibodies. No significance was indicated between AC, ARC and AIDS is any antibody, however, progression from AC to AIDS was poled to high titer and low titer in RTI- and BI-antibodies. Moreover, time course of each antibody levels in the same infected individuals were resulted in no change, going up or down through all the experimental term, though all samples were collected in AC. These results were suggested that the determination factor of each stage in HIV progression would be multiple, and that the various dynamics of RTI-, BI- and PI-antibodies in the same infected individuals might be caused in the term from HIV infection to AIDS progression, prognosis or appearing of the drug resistant strain but stages of the disease.

Acquired Immunodeficiency Syndrome↗