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N Nemoto

Publications and source records attributed to N Nemoto.

At least 19 recordsLinked to original sources
PubMed2006

Coexpression of an unusual form of the EWS-WT1 fusion transcript and interleukin 2/15 receptor betamRNA in a desmoplastic small round cell tumour.

BACKGROUND: The beta chain of the interleukin 2/15 receptor (IL-2/15Rbeta) is induced by the expression of the EWS-WT1. A case of desmoplastic small round cell tumour (DSRCT) expressing only an unusual EWS-WT1 treated by us is reported here. AIM: To characterise an unusual form of EWS-WT1. METHODS: Frozen tissue sections of the axillary tumour were examined using a laser-assisted microdissection technique and reverse transcriptase polymerase chain reaction. RESULTS: The novel fusion of exon 8 of EWS and the defective exon 10 of WT1 (-KTS) was detected. Although it was an unusual form, the coexpression of the present EWS-WT1, IL-2/15Rbeta and Janus kinase (JAK1) mRNA was detected in the tumour cells. IL-2 and signal transducers and activators of transcription (STAT5) mRNA were detected in both tumour and stromal cells. CONCLUSION: The induction of the IL-2/15 receptor signalling pathway may contribute to tumorigenesis in DSRCT through a paracrine or an autocrine system, even though the EWS-WT1 was an unusual form.

Adult↗
PubMed2005

Overexpression of anti-apoptotic Mcl-1 in testicular germ cell tumours.

AIMS: To determine the expression of Mcl-1 in testicular germ cell tumours in order to clarify the role of this anti-apoptotic factor in these tumours. Various members of the Bcl-2 family have been implicated in the apoptotic mechanisms regulating germ cell apoptosis. Mcl-1 is an anti-apoptotic Bcl-2 family member and has recently been reported to be related to the progression of malignancy; however, the involvement of Mcl-1 in the development of germ cell tumours is still unknown. METHODS AND RESULTS: Mcl-1 expression in testicular germ cell tumours was investigated by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). By immunohistochemistry, overexpression of Mcl-1 was present in all germ cell tumours that were studied, including embryonal carcinoma and yolk sac tumour, as well as choriocarcinoma and teratoma. In teratomas, Mcl-1 was widely distributed in the epithelial, myogenic, neural and mesenchymal components. RT-PCR analysis after microdissection revealed high levels of Mcl-1 mRNA in all tumour variants compared with non-neoplastic germ cells. CONCLUSION: Overexpression of anti-apoptotic Mcl-1 may function to enhance the viability of testicular germ cells, thereby leading to tumorigenesis.

Adolescent↗
PubMed2004

Application of compact ultrasound imaging device to postmortem diagnosis.

In regions with low autopsy rates, forensic examiners often have to rely on external findings. Imaging techniques can assist the external examination and provide a more objective diagnosis. The SonoSite 180, a portable ultrasound device, was used for the examination of dead bodies. The influence of different degrees of decomposition was estimated. Even in cases with intestinal gas formation images of internal organs could be obtained with special techniques. Various pathological findings were detected by ultrasound and verified by autopsy (e.g. pericardial tamponade, cardiac hypertrophy, fatty liver, aortic aneurysm, metastatic liver, etc.). The experiences with the SonoSite 180 are promising. The device can be carried to the death scene or to the morgue and therefore serve as a valuable tool for medicolegal applications.

Aorta, Abdominal↗
PubMed2002

A highly potent 26,27-Hexafluoro-1a,25-dihydroxyvitamin D3 on calcification in SV40-transformed human fetal osteoblastic cells.

26,27-hexafluoro-1a,25-dihydroxyvitamin D3 (F6-D3) has been reported to be 5-10 times more potent than 1a,25-dihydroxyvitamin D3[1,25(OH)2D3] in biological systems in vivo and in vitro. However, the effect of F6-D3 on bone formation has yet to be clarified. In the present study, we investigated the effect of F6-D3 on SV40-transfected human fetal osteoblastic cells (SV-HFO) and found it to be about 100 times greater than that of 1,25(OH)2D3 in stimulating calcification. F6-D3 was also about 100 times more effective than 1,25(OH)2D3 in enhancing the expression of mRNA for alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). In the presence of 10?8 M F6-D3 and 10?6 M 1,25(OH)2D3, the calcification began on day 9 and increased up to day 19. Expression of mRNA for ALP and OCN reached a maximum on day 4 and thereafter declined. On the other hand, when osteoblastic cells were incubated with a low level of [1b-3H]-F6-D3- or [1b-3H]-1,25(OH)2D3, each radioactive peak could not be detected. However, on the incubation of osteoblastic cells and radioactive substrate in the presence of ketoconazole, a selective inhibitor of CYP24, a clear peak for each substrate was detected. This suggested that F6-D3 as well as 1,25(OH)2D3 is metabolized by CYP24. Osteoblastic cells were incubated with 10?8 M[1b-3H]-F6-D3 or 10?8 M[1b-3H]-1,25(OH)2D3 for 4, 9, and 14 days. A small peak of 1,25(OH)2D3 was observed and thereafter its level decreased. In addition, two unknown peaks increased when the culture period was extended. In the case of F6-D3, peaks of F6-D3 and 26,27-hexafluoro-23-oxo-1a,25(OH)2D3(23-oxo-F6) were clearly detected, the latter being about 4 times higher than the former. Both peaks was retained up to day 14. The amount of unlabeled F6-D3 and 23-oxo-F6 calculated from the specific radioactivity in the cells may be similar to the amount of 1,25(OH)2D3 and its metabolites. The strong activity of F6-D3 in stimulating calcification may be due to the fact that F6-D3 is much more potent than 1,25(OH)2D3 in enhancing the expression of mRNA for ALP, OCN, and OPN and that the amount of F6-D3 and 23-oxo-F6 accumulated in the cells is much greater than that of 1,25(OH)2D3 and its metabolite.

Alkaline Phosphatase↗
PubMed2002

Histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults.

A few reports in the literature have discussed the histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults, and studies report that intestinal neuronal dysplasia (IND) in adults may develop from IND in infants. The aim of this study was to examine the differences between the histological findings of IND in infants and those in adults, and to assess whether allied diseases of Hirschsprung's disease (HD) in adults should be considered as congenital or acquired diseases. For these purposes, we studied nine adult patients with severe constipation, and an adult patient with acute intestinal obstruction. We routinely examined the patients using barium enema, anorectal manometry and rectal mucosal biopsy. However, in patients suspected of allied diseases, we carried out full-thickness rectal biopsies. In seven operated cases, we also examined resected intestines. The tissue samples were examined using AChE-staining, NADPH-diaphorase staining, HE-staining, and silver impregnation. Histologically, we diagnosed two males as having HD, two males as having IND, five patients (two males and three females) as having hypoganglionosis, and one female as having a degeneration of the intramural plexus. The following conclusions were drawn: 1) Inflammations such as ulcerative colitis or ischemic colitis may cause IND TYPE B in adults whose histological findings are similar to those generally seen in infants; 2) It is suggested that IND is closely related to hypoganglionosis; 3) In hypoganglionosis, a patient with findings of elevated AChE-positive nerve fibers in the mucosa and AChE-positive nerve fibers in an arterial wall may belong to a subtype of IND; 4) Most of the allied diseases of HD in adults may occur as an acquired disease, not as a congenital disease.

Adult↗
PubMed2002

Differential expression of secreted frizzled-related protein 4 in decidual cells during pregnancy.

During pregnancy, the uterus shows marked morphological and physiological changes under the regulation of ovarian steroid. To elucidate the molecular cues of these changes, we tried to identify the transcripts differentially expressed in the pregnant rat uterus by using the suppression subtractive hybridization method. Seven independent clones were isolated and one of the up-regulated genes was secreted frizzled-related protein 4 (sFRP4). sFRP4 contains a Wnt-binding domain and belongs to the secreted frizzled protein family whose members are assumed to function as modulators of the Wnt signal. The expression level of sFRP4 mRNA reached a peak in the pregnant uterus on day 12, when uterine decidualization was almost complete in the rat. In situ hybridization histochemistry revealed that sFRP4 transcripts were observed in the decidual cells. In addition, proliferating cell nuclear antigen (PCNA)-positive cells were shown to be overlapped in decidua, suggesting that sFRP4 mRNA expression was accompanied by the late phase of decidual cell proliferation. Moreover, sFRP4 and estrogen receptor-alpha transcripts were co-localized. Furthermore, we analyzed the regulation of sFRP4 by estrogen using 17 beta-estradiol-treated ovariectomized rats. sFRP4 mRNA was detected in the uterus at 48 h after estrogen treatment, especially in endometrial stroma where PCNA-positive cells were also observed. The results in this study led us to the notion that sFRP4 mRNA may be up-regulated after estrogen treatment in the late phase of uterine cell proliferation.

Animals↗
PubMed2001

An in vitro DNA virus for in vitro protein evolution.

In vitro virus is a molecular construct for in vitro protein evolution, which requires some mechanism to link phenotype to genotype. The first in vitro virus was realized by bonding a nascent protein with its coding mRNA via puromycin in in vitro translation. We report a new construct of in vitro DNA virus. The virion was a covalent cDNA-protein fusion, and virion formation did not require any modification of mRNA. Due to intactness of mRNA, this type of in vitro DNA virus will take the next step toward in vitro autonomous evolution, just like in vivo viral evolution in a cellstat.

DNA Primers↗
PubMed2001

Rapid functional analysis of protein-protein interactions by fluorescent C-terminal labeling and single-molecule imaging.

Detection of protein-protein interactions is a fundamental step to understanding gene function. Here we report a sensitive and rapid method for assaying protein-protein interactions at the single-molecule level. Protein molecules were synthesized in a cell-free translation system in the presence of Cy5-puro, a fluorescent puromycin, using mRNA without a stop codon. The interaction of proteins thus prepared was visualized using a single-molecule imaging technique. As a demonstration of this method, a motor protein, kinesin, was labeled with Cy5-puro at an efficiency of about 90%, and the processive movement of kinesin along microtubules was observed by using total internal reflection microscopy. It took only 2 h from the synthesis of proteins to the functional analysis. This method is applicable to the functional analysis of various kinds of proteins.

Adenosine Triphosphate↗
PubMed2001

Sex-associated expression of mouse hepatic and renal CYP2B enzymes by glucocorticoid hormones.

The expression of Cyp2b9 and Cyp2b10 genes was investigated in kidney, liver, and cultured hepatocytes of adult C57BL/6NCrj mice. The constitutive expression level of CYP2B mRNA in kidney was higher in female than in male mice, as it was in the liver where more CYP2B9 than CYP2B10 was expressed in the females, and more CYP2B10 was expressed in the males. After treatment with dexamethasone (Dex), induction of CYP2B10 mRNA and protein in the kidneys was far greater in male than in female mice. In contrast to Dex, phenobarbital (PB), pregnenolone-16 alpha-carbonitrile (PCN), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) did not induce the expression of the Cyp2b gene in the kidneys of either sex. In the liver, PB, PCN, and DDT induced both CYP2B9 and CYP2B10 in both sexes to the same extent, whereas Dex induced only CYP2B10 and simultaneously suppressed CYP2B9. Dex-inducible expression of CYP2B mRNA was decreased by 11 beta-[4-dimethylamino]phenyl-17 beta-hydroxy-17-[1-propynyl]estra-4,9-dien-3-one (RU-486), in both the kidneys and liver from male mice, and in cultured hepatocytes. However, RU-486 itself induced the expression of CYP2B mRNA in female liver and cultured hepatocytes. Interestingly, RU-486 increased PB-inducible expression of these species in cultured hepatocytes. Gonadectomy increased the expression of CYP2B mRNA in untreated male liver, but suppressed Dex-induced expression in the kidneys of both sexes. These observations suggest that (a) there are multiple regulatory pathways in the expression of Cyp2b genes, one of which used by Dex is mediated via the glucocorticoid receptor, which is different from that used by PB, and (b) sex hormones play a role in the regulation of the sex-dependent expression of Cyp2b genes in the mouse.

Animals↗
PubMed2001

NMR analysis of type III antifreeze protein intramolecular dimer. Structural basis for enhanced activity.

The structure of a new antifreeze protein (AFP) variant, RD3, from antarctic eel pout (Rhigophila dearborni) with enhanced activity has been determined for the first time by nuclear magnetic resonance spectroscopy. RD3 comprises a unique translational topology of two homologous type III AFP globular domains, each containing one flat, ice binding plane. The ice binding plane of the N domain is located approximately 3.5 A "behind" that of the C domain. The two ice binding planes are located laterally with an angle of 32 +/- 12 degrees between the planes. These results suggest that the C domain plane of RD3 binds first to the ice [1010] prism plane in the <0001> direction, which induces successive ice binding of the N domain in the <0101> direction. This manner of ice binding caused by the unique structural topology of RD3 is thought to be crucial for the significant enhancement of antifreeze activity, especially at low AFP concentrations.

Amino Acid Sequence↗
PubMed2001

Localization of estradiol-responsive region in the phenobarbital-responsive enhancer module of mouse Cyp2b-10 gene.

The mouse Cyp2b-10 gene is inducible by treatment with estradiol as well as so-called phenobarbital (PB)-like inducers. To identify 5'-flanking elements responsible for induction by estradiol, we carried out reporter gene assays using a primary mouse hepatocyte culture system. Cyp2b-10 gene-driven luciferase activities were induced by estradiol as well as PB in this system. Deletion analysis demonstrated that the sequence contained within the region from -2331 bp to -2281 bp was responsible for the estradiol-induced luciferase activity. This region corresponds to the core element of PB-responsive enhancer module (PBREM). Several nucleotide mutations in the putative binding sites of the PBREM core element showed that the NR1 site was required for estradiol induction, and the same element was required for PB induction. These results indicate that estradiol induces Cyp2b-10 gene expression via PBREM.

Animals↗
PubMed2001

Stimulative effect of cadmium on prostaglandin E2 production in primary mouse osteoblastic cells.

We have reported that cadmium (Cd) stimulates bone resorption via prostaglandin E2 (PGE2), which is mainly produced in osteoblasts. Prostaglandin (PGs) is regulated by arachidonic acid (AA) release by phospholipase A2 (PLA2) and its conversion to PGs by cyclooxygenase (COX). In the present study, we investigated the possibility that Cd-induced PGE2 synthesis was mediated through PLA2 or COX or both using primary mouse osteoblastic cells in serum-free medium. Cd at 1 microM and above stimulated 14C-AA release from 14C-AA-prelabeled osteoblastic cells. PLA2 activity of cytosolic fraction in Cd-treated cells preferentially hydrolyzed AA at the Sn2 position of phospholipids and was inhibited by arachidonyltrifluoromethyl ketone (AACOCF3), an inhibitor of cytosolic PLA2 (cPLA2). Cd at 1 microM and above increased cPLA2 activity and the level of constitutive cPLA2 mRNA. Secretory PLA2 mRNA was not detected. On the other hand, Cd at 1 microM and above stimulated PGE2 production and its production was inhibited by an inhibitor of COX-2 (NS-398). Cd at 1 microM and above markedly stimulated COX-2 mRNA expression and slightly increased the level of COX-1 mRNA. An inhibitor of COX-1 (varelylsalicylic acid) did not affect Cd-induced PGE2 production. In addition, Cd-induced PGE2 synthesis was inhibited by AA-COCF3, On the other hand, IL-1 alpha, an inducer of COX-2, did not stimulated PGE2 production in present culture system. When IL-1 alpha- or Cd-treated cells were incubated with AA for 10 minutes, IL-1 alpha-treated cells as well as Cd-treated ones caused an increase in PGE2 production. This suggests that the mechanism of Cd-induced PGE2 production is different from that of IL-1 alpha, which may require an activation of cPLA2. From these results, it was found that Cd by itself stimulated PGE2 production by two successive steps that Cd increased cPLA2 activity and then COX-2 induction.

Animals↗
PubMed2001

Application of visual evoked potentials for preoperative estimation of visual function in eyes with dense cataract.

PURPOSE: To determine whether the temporal frequency characteristics of the visual system as determined by visually evoked potentials (VEP) can be used for a preoperative estimation of the visual function in eyes with cataracts. METHODS: Light stimuli driven by a pseudorandom binary sequence (PRBS) of 40950 ms duration were presented and EEG recordings were made from 13 control and 20 patients with cataracts preoperatively and 1 week after cataract operation. The first kernel of the PRBS-VEP was obtained as the first-order cross-correlation function between PRBS and PRBS-VEP. The Fourier transform of this function was used as the temporal frequency characteristic (TFC). RESULTS: The mean +/- standard deviation of the latency and amplitude of the VEP in normal controls were 110.8+/-4.3 ms and 2.01+/-0.67 microV, respectively. A high correlation (r>0.7) between the pre-and postoperative VEP waveform was obtained in 13 eyes (65%), and 14 eyes (70%) in the VEP-TFC curves. The sensitivity of the examination was 73%, 27%, and 91% for the latency, amplitude and TFC of the VEP, respectively. The specificity of the examination was 67%, 100%, and 89% for the same measures. Eleven of 12 eyes with abnormal TFC preoperatively showed retinal or optic nerve lesions postoperatively. False-negative results were seen in cases with delayed corneal edema. CONCLUSION: Postoperative visual function of patients with cataracts can be predicted by preoperative measurement of the TFC obtained by PRBS-VEP.

Adult↗
PubMed2001

Sol-Gel transition behavior of pure iota-carrageenan in both salt-free and added salt states.

This paper describes how strongly the gelation process of iota-carrageenan is affected by addition of metallic ions from the creep and creep recovery, dynamic viscoelasticity (DVE) and DSC measurements. Creep results at T = 25 degrees C indicate that below a polymer concentration C of 3.0 wt % the salt-free system behaves as a viscous solution, and it starts to exhibit viscoelasticity as C exceeds 3.0 wt %. In the range C = 5.0-7.0 wt %, the salt-free system shows gellike behavior whereas the added salt system, measured in the low C range 1.0-2.5 wt %, showed gellike behavior at the same temperature. The sol-gel transition temperature T(c) was determined using Winter's criterion as the temperature at which both G'(omega) and G' '(omega) follow power law behavior with the same exponent n. DSC measurements reveal that salt-free and added salt systems take different types of thermal behavior within the same temperature range. The temperature T(c) is quite close to the gelation temperature T(m) determined from DSC measurement. The Eldrige-Ferry plot was performed to estimate activaton enthalpy, which shows that physical cross-links in the salt-free iota-carrageenan is not strong in comparison with those of samples which contains metal ions. We conclude from the data analysis of C dependence of the plateau modulus using the theory developed by Jones and Marques for rigid networks based on the fractal theories that addition of metallic ions gives rise to a rigid fiber like structure even at low C of iota-carrageenan in contrast to the salt-free system for which a flexible structure has been maintained at higher C.

Biopolymers↗
PubMed2001

Relationship between skeinoid fibers and stromal matrix in gastrointestinal stromal tumors: morphometric analysis with quick-freezing and deep-etching method.

Our previous study of a gastrointestinal autonomic nerve tumor with skeinoid fibers (SF) using the quick-freezing and deep-etching method, suggested that the distance between one radix and a neighboring radix (DRNR) in pre-existing meshwork structures around the tumor cells is consistent with the periodicity of the SF. Therefore, measurement of the DRNR in the meshwork could clarify the significance of the pericellular matrix for SF development. In the present study, we analyzed the meshwork in three cases of gastrointestinal stromal tumor (GIST), which showed different immunohistochemical stainings, but confirmed to have smooth muscle differentiation (SMD) by immunohistochemistry and/or electron microscopy. The DRNR from the three cases of GIST showed similar histogram patterns (a peak of 20-30 nm, mean values of 28.02, 25.74 and 26.45 nm), which were significantly shorter than the periodicity of SF (a peak of 40-45 nm, mean value of 42.14). Although we need further studies with additional GIST cases, we speculate that the pericellular matrix of GIST with SMD is not suitable for SF development.

Abdominal Neoplasms↗
PubMed2001

Phagocytized apoptotic cells in subcutaneous panniculitis-like T-cell lymphoma.

We reported on a case of subcutaneous panniculitis-like T-cell lymphoma (SPTCL) with multiple erythematous nodular lesions on the extremities, trunk and face. Histological examination of an excised lesion revealed a dense infiltrate of markedly atypical T-lymphoid cells expressing the CD8+ phenotype located in the subcutaneous tissue with histiocyte-phagocytizing apoptotic cells. The 'bean-bag' histiocytic cells, the characteristic finding of SPTCL, are considered to be products of haemophagocytosis. In our case the 'bean-bag' cells were produced by phagocytosis of apoptotic bodies, as confirmed by electron microscopy. It is suspected that 'bean-bag' cells are related not to haemophagocytosis but to phagocytosis of apoptotic cells in the CD8+ T-cell type of SPTCL.

Adult↗