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Yasuko Yoshida

Publications and source records attributed to Yasuko Yoshida.

11 recordsLinked to original sources
PubMed2005

Expression profiling using a tumor-specific cDNA microarray predicts the prognosis of intermediate risk neuroblastomas.

To predict the prognosis of neuroblastoma patients and choose a better therapeutic protocol, we developed a cDNA microarray carrying 5340 genes obtained from primary neuroblastomas and examined 136 tumor samples. We made a probabilistic output statistical classifier that provided a high accuracy in prognosis prediction (89% at 5 years) and a highly reliable method to validate it. Kaplan-Meier analysis indicated that the patients in an intermediate group defined by existing markers are divided by microarray into two further groups with 5 year survivals for 36% and 89% of patients (p < 10(-4)), i.e., with unfavorably and favorably predicted neuroblastomas, respectively. According to these results, we developed a gene subset chip for a clinical tool, for which our classifier exhibited 88% prediction accuracy.

Algorithms↗
PubMed2004

Identification and characterization of a novel gene, C13orf25, as a target for 13q31-q32 amplification in malignant lymphoma.

The amplification at 13q31-q32 has been reported in not only hematopoietic malignancies but also in other solid tumors. We identified previously frequent amplification of chromosomal band 13q31-q32 in 70 cases of diffuse large B-cell lymphoma patients by conventional comparative genomic hybridization analysis. In an attempt to identify a candidate gene within this region, we used array comparative genomic hybridization and fluorescent in situ hybridization to map the 13q31-q32 amplicon. We then screened the 65 expressed sequence tags and Glypican 5 (GPC5) by reverse transcription-PCR and Northern blotting. As a result, we identified a novel gene, designated Chromosome 13 open reading frame 25 (C13orf25), which was overexpressed in B-cell lymphoma cell lines and diffuse large B-cell lymphoma patients with 13q31-q32 amplifications. However, GPC5, which has been reported to be a target gene for 13q31-q32 amplification, was truncated in one cell line, Rec1, possessing the amplification, and its expression in various cell lines with amplification at 13q31-q32 was not significantly different from that in other cell lines without amplification, suggesting that GPC5 is not likely to be the candidate gene. Additional analysis identified two major transcripts in the C13orf25 gene. The two transcripts A and B predicted open reading frames of 32 and 70-amino acid polypeptides, respectively. The former has been reported as bA121J7.2, which is conserved among species. Transcript-B also contained seven mature microRNAs in its untranslated region. These results suggest that the C13orf25 gene is the most likely candidate gene for the 13q31-q32 amplicon found in hematopoietic malignancies.

Amino Acid Sequence↗
PubMed2004

Biphasic expression of two paracrine melanogenic cytokines, stem cell factor and endothelin-1, in ultraviolet B-induced human melanogenesis.

Stem cell factor (SCF) and endothelin-1 (ET-1) have been reported to be up-regulated at the protein and gene levels in human epidermis after ultraviolet B (UVB) irradiation and to play central roles in UVB-induced pigmentation. However, little is known about the time sequence of SCF and ET-1 expression in UVB-exposed human epidermis and the coordination of their roles during epidermal pigmentation. To clarify such parameters in UVB-exposed human skin, we measured the expression patterns of SCF and ET-1 (as well as of their corresponding receptors) at the gene level at various times during UVB-induced human pigmentation. When human forearm skin was exposed to UVB radiation at two minimal erythemal doses, the expression of SCF mRNA transcripts was significantly enhanced at 3 days after irradiation with an early decrease and subsequently constant expression of SCF receptor (c-KIT) mRNA transcripts. In contrast, up-regulation of ET-1 and endothelin B receptor (ET(B)R) mRNA expression was synchronized at 5 to 10 days after irradiation in concert with an increased expression of tyrosinase mRNA transcripts and the increase in pigmentation. In parallel the expression of tyrosinase and ET(B)R proteins as well as ET-1 was up-regulated at 7 to 10 days after irradiation, whereas KIT protein decreased at 3 days after irradiation and returned to the nonirradiated control level at 5 days after irradiation. When cultured human melanocytes were treated with human recombinant SCF, ET(B)R protein expression and the binding of (125)I-labeled ET-1 to the ET(B)R were significantly increased, further suggesting the preferential and coordinated role of early expression of SCF in UVB-induced melanogenesis. These findings suggest that SCF/KIT signaling is predominantly involved in the early phase of UVB-induced human pigmentation during which it stimulates the ET-1/ET(B)R linkage that is associated with the later phase of UVB-induced melanogenesis.

Cells, Cultured↗
PubMed2003

Detection of enteric viruses in municipal sewage sludge by a combination of the enzymatic virus elution method and RT-PCR.

Pathogenic enteric viruses can be retained in municipal sewage sludge as has been reported by many researchers. Although the RT-PCR technique has been extensively employed for the virus detection from various environmental samples, the application of RT-PCR to the detection of viruses in sewage sludge has the difficulty because of inhibitory substances to the gene amplification. However, a combination of the enzymatic virus elution (EVE) method with RT-PCR made it possible to effectively detect viruses in sewage sludge. The enzymatic breakdown of sludge flocs in the EVE method enhanced the virus elution from poliovirus 1 (PV1)-inoculated sewage sludge, and the detection of PV1 was performed by RT-PCR without any inhibitions. On the contrary, the application of RT-PCR to the viral assay in the US EPA method using the 10% beef extract solution was not practical because of inhibitions to the viral gene amplification. The combination of the EVE method using lysozyme (polysaccharide-degrading enzyme), papain (protease), and chymotrypsin (protease) with RT-PCR resulted in a virus recovery efficiency of 31%, but a synergistic effect of these enzymes on the virus recovery efficiency was not observed. The EVE method using lysozyme or papain could be a promising procedure for the virus elution from sewage sludge in detecting these viruses with RT-PCR.

Biological Assay↗
PubMed2003

Short report: a major genotype of Japanese encephalitis virus currently circulating in Japan.

A 240-nucleotide sequence of the capsid/premembrane gene region of 23 Japanese encephalitis virus (JEV) strains isolated in Tokyo and Oita, Japan was determined and phylogenetic analyses were performed. All the strains clustered into two distinct genotypes (III and I). All strains isolated before 1991 belonged to genotype III, while those isolated after 1994 belonged to genotype I. In addition, the strains of the genotype I isolated in Japan showed a close genetic relationship with those from Korea and Malaysia.

Base Sequence↗
PubMed2002

Fission yeast Mor2/Cps12, a protein similar to Drosophila Furry, is essential for cell morphogenesis and its mutation induces Wee1-dependent G(2) delay.

Fission yeast cells identify growing regions at the opposite ends of the cell, producing the rod-like shape. The positioning of the growth zone(s) and the polarized growth require CLIP170-like protein Tip1 and the Ndr kinase Orb6, respectively. Here, we show that the mor2/cps12 mutation disrupts the localization of F-actin at the cell ends, producing spherical cells and concomitantly inducing a G(2) delay at 36 degrees C. Mor2 is important for the localization of F-actin at the cell end(s) but not at the medial region, and is essential for the restriction of the growth zone(s) where Tip1 targets. Mor2 is homologous to the Drosophila Furry protein, which is required to maintain the integrity of cellular extensions, and is localized at both cell ends and the medial region of the cell in an actin-dependent fashion. Cellular localization of Mor2 and Orb6 was interdependent. The tyrosine kinase Wee1 is necessary for the G(2) delay and maintenance of viability of the mor2 mutant. These results indicate that Mor2 plays an essential role in cell morphogenesis in concert with Orb6, and the mutation activates the mechanism coordinating morphogenesis with cell cycle progression.

Amino Acid Sequence↗
PubMed2002

A split cord malformation with paresis of the unilateral lower limb: case report.

BACKGROUND: We report a rare case of split cord malformation. CASE DESCRIPTION: A female neonate presented with split cord malformation (SCM) manifesting as right lower limb paresis. Myelomeningocele and meningocele were found in the lumbosacral region at birth. Magnetic resonance imaging (MRI) demonstrated division of the spinal cord into two hemicords below the T5 level. The right hemicord formed a hemimyelomeningocele and the left hemicord terminated in the low-lying conus. Three-dimensional computed tomography (3D CT) showed extensive vertebral body abnormalities. The hemimyelomeningocele was repaired 1 day after birth, and septectomy and the repair of the meningocele were performed when the patient was 1 year old. The patient has been followed up as an outpatient, and has residual right lower limb paresis. CONCLUSION: SCM can be associated with multiple spinal abnormalities. MRI and 3D-CT are useful for identifying such abnormalities and planning the surgical treatment.

Abnormalities, Multiple↗
PubMed2002

Identification of sources contributing to Mid-Atlantic regional aerosol.

Source types or source regions contributing to the concentration of atmospheric fine particles measured at Brigantine National Wildlife Refuge, NJ, were identified using a factor analysis model called Positive Matrix Factorization (PMF). Cluster analysis of backward air trajectories on days of high- and low-factor concentrations was used to link factors to potential source regions. Brigantine is a Class I visibility area with few local sources in the center of the eastern urban corridor and is therefore a good location to study Mid-Atlantic regional aerosol. Sulfate (expressed as ammonium sulfate) was the most abundant species, accounting for 49% of annual average fine mass. Organic compounds (22%; expressed as 1.4 x organic carbon) and ammonium nitrate (10%) were the next abundant species. Some evidence herein suggests that secondary organic aerosol formation is an important contributor to summertime regional aerosol. Nine factors were identified that contributed to PM2.5 mass concentrations: coal combustion factors (66%, summer and winter), sea salt factors (9%, fresh and aged), motor vehicle/mixed combustion (8%), diesel/Zn-Pb (6%), incinerator/industrial (5%), oil combustion (4%), and soil (2%). The aged sea salt concentrations were highest in springtime, when the land breeze-sea breeze cycle is strongest. Comparison of backward air trajectories of high- and low-concentration days suggests that Brigantine is surrounded by sources of oil combustion, motor vehicle/mixed combustion, and waste incinerator/industrial emissions that together account for 17% of PM2.5 mass. The diesel/Zn-Pb factor was associated with sources north and west of Brigantine. Coal combustion factors were associated with coal-fired power plants west and southwest of the site. Particulate carbon was associated not only with oil combustion, motor vehicle/mixed combustion, waste incinerator/industrial, and diesel/Pb-Zn, but also with the coal combustion factors, perhaps through common transport.

Aerosols↗
PubMed1999

2-Piperidone Type of Chiral Building Block for 3-Piperidinol Alkaloid Synthesis.

An enantiomeric pair of a new 2-piperidone type of chiral building block (1) has been prepared by bakers' yeast reduction of beta-keto ester (2) or lipase-mediated transesterification of hydroxy ester (+/-)-(1), derived from NaBH(4) reduction of 2, in enantiopure form. The absolute stereochemistry of (-)-1 was verified by its conversion to known piperidine (-)-3, an intermediate for the synthesis of (-)-spectaline. The 2-piperidone (-)-1 was converted to all four diastereomers of 2,6-disubstituted 3-piperidinol chiral building blocks on the basis of homologation of (-)-1 at the lactam carbonyl using the Eschenmoser method via corresponding thiolactams (-)-9, (-)-20, (-)-25, (-)-27, and (-)-34, followed by stereocontrolled reduction of the resulting vinylogous urethanes (+)-10, (+)-15, (+)-23, (+)-28, and (+)-32, respectively, and epimerization of the hydroxyls at the 3-position [(-)-16 via (+)-17 to (-)-18 and (+)-29 via (+)-30 to (+)-31]. The versatility of these chiral buliding blocks has been demonstrated by the chiral synthesis of the 3-piperidinol alkaloids (+)-prosafrinine, (-)-iso-6-cassine, (-)-prosophylline, and (-)-prosopinine from (-)-37, (-)-14, (+)-36, and (-)-26, respectively.

Journal Article↗
PubMedDate not supplied

Comparison of age-related changes in wrinkling and sagging of the skin in Caucasian females and in Japanese females.

We compared age-related changes in wrinkles in eight areas of facial skin (forehead, glabella, upper eyelid, corner of the eye, lower eyelid, nasolabial groove, cheek, and corner of the mouth) and sagging in the subzygomatic area of Caucasian females and of Japanese females. The subjects studied included 85 healthy Caucasian females (ages 20-69 years) living in Cincinnati in the U.S. and 70 Japanese females (ages 20-69 years) living in Tokyo. Photos of the face in frontal and in oblique 45 degrees views were analyzed. Wrinkles in the face and sagging in the subzygomatic area were graded on Japanese photoscales, respectively, by the same experienced observer. The wrinkle score increased with age in all eight areas of the face examined in Caucasian females as well as in Japanese females. In the group aged 20-29 years, the wrinkle score in each area was significantly higher in Caucasian females than in Japanese females. The wrinkle scores in the forehead, glabella, upper eyelid, and corner of the eye were similar at advanced ages between the two groups, while the wrinkle scores in lower areas of the face (lower eyelid, nasolabial groove, cheek, and corner of the mouth) were markedly higher in Caucasian females than in Japanese females in each age group, and reached an upper limit at advanced ages in Caucasian females. The sagging score also increased with age in Caucasian females as well as in Japanese females. The sagging score was significantly higher in Caucasian females than in Japanese females in the groups aged 40 years or more. These results suggest more marked wrinkle formation in all areas of the face in younger age groups of Caucasian females living in North America than in Japanese females living in Tokyo. In particular, Caucasian females showed marked age-related wrinkle formation in the lower areas of the face, probably due to sagging in the subzygomatic area, which suggests a higher susceptibility to sagging in the subzygomatic area of Caucasian females.

Adult↗