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K Toriyama

Publications and source records attributed to K Toriyama.

At least 55 records · Page 3Linked to original sources
PubMed1994

Nucleotide sequence of a rice cDNA similar to a maize NADP-dependent malic enzyme.

We have isolated a rice cDNA clone that is homologous to the gene for the maize NADP-dependent malic enzyme (EC 1.1.1.40; NADP-ME). The deduced amino acid sequence coded for by the cDNA indicates a high level of homology to chloroplast type NADP-ME, including a transit peptide with pronounced hydrophobic properties at the amino terminus. Northern blot analysis indicates that the expression of this gene is regulated by external stress such as submergence.

Amino Acid Sequence↗
PubMed1994

Molecular characterization of rice genes specifically expressed in the anther tapetum.

In situ localization of mRNA was carried out on two cDNAs (Osc4 and Osc6) that had been isolated from rice anthers at the microspore stage. The mRNA corresponding to each cDNA was shown to be localized only in the tapetal cells of the rice immature anthers, but not in the microspores or the mature pollen. The corresponding genomic clone, Osg6B, was isolated, and its 5'-upstream region was found to regulate beta-glucuronidase expression in the tapetum of transgenic tobacco. A set of 5' deletions was also generated and a 1095 bp 5' region was revealed to be necessary for activation of the Osg6B promoter in transgenic tobacco.

Base Sequence↗
PubMed1994

Modification of strain-specific femoral bone density by bone marrow-derived factors administered neonatally: a study on the spontaneously osteoporotic mouse, SAMP6.

SAMP6 is a recently developed strain of osteoporotic mice, and SAMP2 is a control for SAMP6 and has a higher peak bone mass. The bone mass of SAMP6 was increased until 2 months of age when a lysate of cells derived from the bone marrow of SAMP2 was injected at 1 or 4 days of age, but it was not increased when the lysate was injected at 21 days of age. No effect on bone mass was observed when lysates of other cells, bovine serum albumin or heat-inactivated lysate of bone marrow-derived cells of SAMP2, were injected. The ability to increase bone mass was not in the supernatant but in the pellet obtained by ultracentrifugation (105,000 g) of the lysate of bone marrow-derived cells of SAMP2. The lysate did not change the osteoclast surface but changed the appositional bone formation. In conclusion, the lysate of cells derived from the bone marrow of SAMP2 contains factors which can increase the bone mass of SAMP6, and these factors are present in the pellet obtained by ultracentrifugation.

Animals↗
PubMed1994

A high degree of homology exists between the protein encoded by SLG and the S receptor domain encoded by SRK in self-incompatible Brassica campestris L.

The sporophytic self-incompatibility system in Brassica campestris is controlled by multiple alleles of a single locus, S. We isolated and characterized cDNA clones that correspond to genes for S-glycoprotein (SLG) and S-receptor kinase (SRK) from an S9-homozygous strain. An SRK9 fragment was amplified by the polymerase chain reaction (PCR) by use of primers that corresponded to regions of the gene for the extracellular receptor domain (S-domain) and the kinase domain. The fragment was used as a probe to isolate an SRK9 cDNA clone from the cDNA library of stigmas of an S9-homozygote. An SLG9 cDNA clone was also isolated from the library by use of SLG8 cDNA as a probe. Restriction fragment length polymorphism (RFLP) linkage analysis of the F2 plants from an S8S9 hybrid demonstrated that the SRK and SLG genes were tightly linked to one another and were also linked to S-genotypes, as determined by pollination tests. The transcripts of SRK9 and SLG9 were detected in stigmas, but not in anthers or leaves. The cytoplasmic kinase domain encoded by SRK9 contained amino acid sequences that are conserved in serine/threonine kinases. The nucleotide sequence encoding the S-domain of SRK9 was 98.4% homologous to that of SLG9 at the nucleotide level. This observation suggests the existence of a mechanism for maintaining a high degree of similarity between SLG and the region that encodes the S-domain of SRK.

Base Sequence↗
PubMed1994

[Surgical treatment of a long-term decubitus ulcer].

A 64-year-old male presented with a large decubitus ulcer of the sacrum which had not healed for thirteen years in spite of various conservative treatments. His primary disease was paraplegia following spondylitis. Although he was not ambulatory, he was able to manage a wheelchair. The decubitus, which had a 8 x 13 cm dead space, was successfully closed with a single operation using two fasciocutaneous flaps. The patient was discharged two months postoperatively. The medical cost of his treatment before and after the surgery was investigated. The expense including the surgery and postoperative care until discharge was five times more than the monthly cost of the preoperative period. These findings suggest that a decubitus ulcer which does not respond to conservative treatments for more than several months should be considered for a surgical management, as long as the patient's general condition permits an operation.

Aged↗
PubMed1994

A clinicpathological study of hepatocellular carcinoma in Nagasaki, south-western Japan: the association of hepatitis B and C viruses.

Hepatocellular carcinoma (HCC) is one of the most prevalent cancers in Japan as well as Southeast Asia and Africa. On 89 patients with HCC in the Nagasaki City area were performed serological examinations and histopathological studies. The number of HBsAg positive and anti-HCV positive was three (3%), HBsAg positive and anti-HCV negative 21 (24%), HBsAg negative and anti-HCV positive 58 (65%) and HBsAg negative and anti-HCV negative seven (8%). These results strongly suggest that HCV infection is a more important factor in the development of HCC than HBV infection. The HBsAg negative and anti-HCV positive group showed a higher mean age and a higher male to female ratio than the HBsAg positive and anti-HCV negative group. Histological examinations showed no differences between these two groups. In addition, all cases were complicated with chronic hepatitis (CH) or liver cirrhosis (LC) in adjacent liver tissue. These findings suggest that CH and LC seem to play an important role in the pathogenesis of HCC.

Aged↗
PubMed1993

Variations in the distribution, frequency, and phenotype of Langerhans cells during the evolution of malignant melanoma of the skin.

We examined the frequency, distribution, and immunophenotype (S-100 protein, CD1) of epidermal Langerhans cells (LC) in the epidermis overlying primary melanoma, and dermal dendritic cells (DC) in the dermis deep to melanoma, and in adjacent normal skin. There is a substantial reduction in S-100+ LC and a lesser decline in CD1+ LC in the epidermis over melanoma. There is a simultaneous increase in the frequency of cells expressing these phenotypes in the dermis deep to tumor. Double-staining studies in progress show coexpression of S-100 and CD1 in most of these cells. The depletion of S-100+/CD1+ DC from the peritumoral epidermis is maximum in deeper (Clark level III-V) and thicker (> 0.76 mm) tumors. The reduction in total DC in peritumoral epidermis is, however, proportionally less than the reduction in S-100+/CD1+ DC owing to an increase in cells that are S-100-/CD1+. The proportion of S-100+/CD1+ dermal DC deep to tumor is similar to that in normal epidermis and dermis, suggesting that there is no increased migration of S-100-/CD1+ DC from tumor-associated epidermis to subjacent dermis. Non-dendritic leukocytes in the dermis deep to tumor were increased in frequency, maximally in the dermis deep to thinner and more superficial melanomas. Most such cells were T lymphocytes with helper/inducer cells predominating. The data presented show substantial alterations in the frequency, distribution, and phenotype of LC/DC as melanoma evolves, alterations that may be critical for development of effective tumor-directed immunity.

Antigens, CD↗
PubMed1993

Light microscopic radioautographic study on DNA synthesis in aging mice corneas.

The morphological change and DNA synthesis of the aging mice corneal cells were investigated by light microscopic radioautography after injection of tritiated thymidine. The result showed that the incorporation of tritiated thymidine in corneal cells changed with aging. The sites of tritiated thymidine incorporation were located in the epithelium from postnatal day 19 to 1 year after birth, in the stroma and endothelium from prenatal day 19 to postnatal day 8 only. The labeling index in the epithelial cells reached its highest value at 1 month after birth. Labelled stromal and endothelial cells reached their peaks simultaneously on the third day after birth and disappeared completely from postnatal 1 month onwards. The thickness of the cornea increased obviously at one month and there were no notable morphological change thereafter. Our investigation provides for the first time a systematic study on the age-related changes of DNA synthesis and construction in the aging mice corneas.

Aging↗
PubMed1992

Isolation of genes abundantly expressed in rice anthers at the microspore stage.

A cDNA library of rice (Oryza sativa L.) has been constructed from anthers at an early stage of pollen development. By differential screening of the library, we have isolated cDNAs of two genes, designated as Osc4 and Osc6, that are abundantly expressed in anthers containing tetrads and uninucleate microspores, but are not expressed in leaves or roots. Expression of Osc4 is absent in mature anthers, while Osc6 is present although the expression decays during pollen maturation. A comparison of the nucleotide and deduced amino acid sequences with those in data banks has not shown significant homology to known molecules.

Amino Acid Sequence↗
PubMed1992

Flow cytometric DNA analysis of vascular soft tissue tumors, including African endemic-type Kaposi's sarcoma.

Vascular tumors of the soft tissue display a wide spectrum of histologic features and biologic behavior. Flow cytometric DNA analysis was performed on 40 vascular tumors, including nine African endemic-type Kaposi's sarcomas, nine angiosarcomas, seven hemangiopericytomas, six glomus tumors, and nine capillary hemangiomas. Six of the nine angiosarcoma cases (67%) and one of the seven hemangiopericytomas cases (14%) were aneuploid. All benign vascular tumors and Kaposi's sarcomas were diploid. Clinically, five of the six angiosarcoma patients with aneuploidy died within 2 to 28 months, while the remaining patient, who had the smallest tumor (2 x 1 cm), survived more than 4 years after the initial diagnosis was made. All three angiosarcoma patients with diploidy died within 10 to 14 months. One hemangiopericytoma patient with aneuploidy died within 1 month. No cases of benign tumor recurred. These results suggest that most vascular tumors, which generally follow a benign clinical course, were diploid and that the majority of those with a poor outcome were aneuploid. However, flow cytometrically assessed DNA ploidy has no prognostic value in angiosarcomas or hemangiopericytomas.

Adolescent↗
PubMed1992

The existence of distinct classes of prostaglandin E2 receptors mediating adenylate cyclase and phospholipase C pathways in osteoblastic clone MC3T3-E1.

We have reported previously that PGE2 evoked an increase in intracellular calcium level ([Ca2+]i) in mouse osteoblastic cells (1). Here, we investigated the effects of PGE1 and PGF2 alpha on cAMP production and [Ca2+]i in comparison with those of PGE2. In osteoblastic clone, MC3T3-E1 cells, PGE1 stimulated cAMP production, but had no effect on [Ca2+]i, whereas PGF2 alpha evoked only [Ca2+]i increase. In contrast, PGE2 not only stimulated cAMP production, but also increased [Ca2+]i. From the Scatchard plot analysis of PGE2 it was confirmed that there were two classes of PGE2 binding sites (Kd value, 9.2 nM; binding site, 29 fmole/mg protein, and Kd value, 134 nM; binding site, 148 fmole/mg protein). As the increase in [Ca2+]i was caused by PGF2 alpha and PGE2, but not by PGE1, we investigated the displacement of [3H]-PGF2 alpha binding. The displacement capacity of unlabeled PGE2 was about 110 of that of PGF2 alpha, while that of PGE1 was very low even at 500-fold excess. These data indicate the possibility that the dual action of PGE2 is mediated by distinct receptor systems.

Adenylyl Cyclases↗
PubMed1992

Polyarteritis nodosa with aortic dissection: necrotizing vasculitis of the vasa vasorum.

A 59-year-old woman was admitted to our hospital with acute onset of chest pain. She had experienced high fever, weight loss, polyarthralgia, myalgia, polyneuropathy and hallucinations for 3 years before admission. The diagnosis of polyarteritis nodosa with hepatitis B surface antigenemia was made by muscle biopsy and serological examinations, and administration of prednisolone induced remission of all the manifestations. After developing the acute attack of severe chest pain, she died suddenly. At autopsy, a DeBakey type 1 aortic dissection was found and the immediate cause of death was found to be cardiac tamponade secondary to rupture of the aortic dissection. Microscopically, necrotizing inflammatory lesions were present in the medium sized vascular arteries throughout her body. Furthermore, necrotizing vasculitis was also found in the vasa vasorum of the adventitia and media of the thoracic aorta. The dissecting lesion was seen in the outer layer of the media. Our results suggest that spontaneous dissection of the aorta may be attributed to necrotizing vasculitis of the vasa vasorum.

Aortic Dissection↗
PubMed1991

A Brassica S locus gene promoter directs sporophytic expression in the anther tapetum of transgenic Arabidopsis.

The S locus glycoprotein (SLG) gene of Brassica encodes stigmatic glycoproteins that are implicated in the pollen-stigma interaction of self-incompatibility. We have transformed the related plant Arabidopsis thaliana with a chimaeric gene consisting of the promoter region of an SLG gene fused to the reporter gene beta-glucuronidase (GUS). In transgenic plants the gene was expressed in two cell types of the flower. In stigmas, the timing and distribution of GUS activity was similar to that previously described for SLG expression in Brassica. In anthers, expression was detected at an earlier stage of flower development with GUS activity restricted to the tapetal cell layer. The novel finding of SLG-promoter activity in the anther supports the hypothesis that sporophytic control of self-incompatibility is a result of SLG-gene expression in the tapetum.

DNA, Recombinant↗