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S Yasumoto

Publications and source records attributed to S Yasumoto.

At least 19 recordsLinked to original sources
PubMed2006

Expression of phosphorylated Stat3, cyclin D1 and Bcl-xL in extramammary Paget disease.

BACKGROUND: Stat3 (Signal transducer and activator of transcription-3) is an oncogene that plays a critical role in regulating fundamental processes associated with malignant transformation and cell survival. It participates in oncogenesis through upregulation of genes encoding apoptosis inhibitors (Bcl-xL) and cell cycle regulators (cyclin D1). The expression of Stat3, Bcl-xL and cyclin D1 protein has not been investigated in extramammary Paget disease (EMPD). OBJECTIVES: To study the expression of phosphorylated Stat3 (p-Stat3), Bcl-xL and cyclin D1 protein in EMPD and to evaluate the relationships among them. METHODS: Thirty-six tissue samples from 34 patients with primary EMPD were subjected to immunohistochemical staining for p-Stat3, cyclin D1 and Bcl-xL. RESULTS: Thirty-five of 36 specimens were clearly positive for p-Stat3 in EMPD, while 30 of 36 and 32 of 36 were positive for cyclin D1 and Bcl-xL expression, respectively. In all of four invasive EMPD specimens, strong and frequent expression of these three molecules was evident; moreover, two invasive EMPD specimens with lymph nodal metastasis showed very strong nuclear and membranous p-Stat3 staining. Two metastatic lymph node specimens showed very strong nuclear and local membrane p-Stat3 staining. There were significant correlations between p-Stat3 and cyclin D1 expression and between p-Stat3 and Bcl-xL expression. CONCLUSIONS: Our study shows that the expression of p-Stat3, cyclin D1 and Bcl-xL may play a pivotal role in the pathogenesis of EMPD.

Adult↗
PubMed2006

Expression of insulin-like growth factor-1 receptor, p-AKT and p-ERK1/2 protein in extramammary Paget's disease.

BACKGROUND: The insulin-like growth factor-1 (IGF-1) receptor (R)-induced phosphatidylinositol 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MAPK)/ERK signal transduction cascade, which have critical roles in prevention of apoptosis and regulation of cell cycle progression, plays an important role in tumorigenesis. The expression of IGF-1R, AKT and ERK1/2 has been described in some human malignancies, but not in extramammary Paget's disease (EMPD). OBJECTIVES: To study the expression of IGF-1R, p-AKT and p-ERK1/2 in EMPD and to evaluate the relationships among them. METHODS: Thirty-six tissue samples of 34 patients with primary EMPD were subjected to immunohistochemical staining for IGF-1R, p-AKT and p-ERK1/2. RESULTS: Of thirty-six EMPD tissue samples, 34, 34 and 28 were positive for IGF-IR, p-AKT and p-ERK1/2 expression, respectively; 27, 23 and 17 of the 36 specimens stained positive for IGF-IR, p-AKT and p-ERK1/2 in more than half of Paget's cells, respectively. There were significant correlations between the IGF-1R and p-AKT expression as well as between IGF-1R and p-ERK1/2 expression. Taken together, these results indicate that IGF-1R is overexpressed, and AKT and ERK1/2 are frequently phosphorylated in EMPD. CONCLUSIONS: Our study shows that the expression of IGF-1R and the induction of p-AKT and the p-ERK1/2 pathway may play an important role in the pathogenesis of EMPD. The IGF-IR system might be a potential therapeutic target in EMPD.

Aged↗
PubMed2004

Effect of localization of missense mutations in SCN1A on epilepsy phenotype severity.

BACKGROUND AND METHODS: Many missense mutations in the voltage-gated sodium channel subunit gene SCN1A were identified in patients with generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy of infancy (SMEI), although GEFS+ is distinct from SMEI in terms of clinical symptoms, severity, prognosis, and responses to antiepileptic drugs. The authors analyzed the localization of missense mutations in SCN1A identified in patients with GEFS+ and SMEI to clarify the phenotype-genotype relationships. RESULTS: Mutations in SMEI occurred more frequently in the "pore" regions of SCN1A than did those in GEFS+. These SMEI mutations in the "pore" regions were more strongly associated than mutations in other regions with the presence of ataxia and tendency to early onset of disease. The possibility of participation of ion selectivity dysfunction of the channel in the pathogenesis of SMEI was suggested by a mutation in the pore region (R946C) identified in a SMEI patient. CONCLUSIONS: There was a significant phenotype-genotype relationship in generalized epilepsy with febrile seizures plus and severe myoclonic epilepsy of infancy with SCN1A missense mutations. More severe sodium channel dysfunctions including abnormal ion selectivity that are caused by mutations in the pore regions may be involved in the pathogenesis of SMEI.

Age of Onset↗
PubMed2003

Gene expression of telomerase related proteins in human normal oral and ectocervical epithelial cells.

We analyzed telomerase activities and gene expressions of telomerase components: hTERT, hTR, hTEP1, telomeric repeat binding factors: TRF1, TRF2, and c-myc, Max and Mad in human normal oral and ectocervical epithelial keratinocytes, comparing with those of squamous carcinoma cells and HPV16- or SV40-immortalized cells. Significant telomerase activity and hTERT expression were detected in primary keratinocytes. However, both were dramatically down-regulated during serial passages. The down-regulation of hTERT mRNA was associated with augmented expression of TRF1. Expression of c-myc was slightly decreased, whereas Mad was expressed in parallel with that of hTERT during passages. We also detected an alternate splicing of hTERT transcript in two of four cancer cells and normal aged epithelial cells. These results suggest that the senescence of normal oral and ectocervical keratinocytes is accompanied with up-regulation of TRF1 and down-regulation of telomerase activity due to transcriptional suppression of active form of hTERT in vitro.

Alternative Splicing↗
PubMed2002

Clinical, histopathological and immunological distinction in two cases of IgA pemphigus.

Two cases of IgA pemphigus, one of the subcorneal pustular dermatosis (SPD) type and one of the intraepidermal neutrophilic IgA dermatosis (IEN) type, are described. IgA anti-keratinocyte cell surface antibodies reacted only with the uppermost epidermis in the SPD type but with the entire epidermis in the IEN type. A cDNA transfection test for desmocollins (Dsc) revealed that IgA antibodies of the SPD type reacted with Dsc1, but the IEN type did not react with any of the Dsc isoforms (Dsc1-3). ELISA for desmoglein 1 (Dsg1) and Dsg3 showed that neither of the cases had antibodies to Dsg - of either the IgG or IgA subtype. These results confirm that the autoantigen in SPD-type IgA pemphigus is Dsc1, whereas the antigen in most cases of IEN-type IgA pemphigus is unknown.

Aged↗
PubMed2002

Direct and indirect actions of dopamine on the membrane potential in medium spiny neurons of the mouse neostriatum.

Many studies have shown dopamine (DA) to have a modulatory effect on neuronal excitability, which cannot be simply classified as excitatory or inhibitory in the neostriatum. To clarify whether the responses to DA (10-30 microM) are excitatory or inhibitory in the mouse medium spiny neurons, we examined the effects of DA agonists on the synchronous potential trajectory from the resting potential to the subthreshold potential. The DA-induced potential changes, which were estimated at the subthreshold potential (approximately -60 mV), were summarized as the combination of three kinds of responses: an initial hyperpolarization lasting approximately 1 min and a slow depolarization and/or hyperpolarization lasting more than 20 min. A D(1)-like receptor agonist, R(+)-6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF81297, 1 microM) mainly induced the initial hyperpolarization and slow depolarization. A D(2)-like receptor agonist, trans-(-)-4aR-4,4a,5,6,7,8,8a,9-octahydro-5-propyl-1H-pyrazolo[3,4-g]quinoline hydrochloride (quinpirole, 1 microM), mainly induced the initial hyperpolarization and slow hyperpolarization. D(1)-like receptor antagonist R(+)-7-chloro-8-hydroxy-3-methyl1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride (SCH23390, 1 microM) depressed both the initial hyperpolarization and slow depolarization. D(2)-like receptor antagonist sulpiride (1 microM) depressed all the DA-induced responses except for the slow depolarization. TTX (0.5 microM) abolished all the DA-induced responses. Bicuculline (20 microM) and atropine (1 microM) abolished the DA-induced initial hyperpolarization and slow depolarization, respectively. Either DL-2-amino-5-phosphonopentanoic acid (AP5; 100 microM) or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 20 microM) blocked both the initial hyperpolarization and slow depolarization. The application of exogenous glutamate (Glu) mimicked the initial hyperpolarization and slow depolarization. These results suggest that the initial hyperpolarization is mainly due to GABA release via the cooperative action of D(1)- and D(2)-like receptors and Glu receptors in GABAergic interneurons, whereas the slow depolarization is mediated by acetylcholine (ACh) release via the cooperative action of mainly D(1)-like receptors and Glu receptors in cholinergic interneurons. The potential oscillation was generated at the subthreshold level in a Ba(2+)-, AP5-, CNQX-, bicuculline-, and atropine-containing medium. The oscillation depressed after the addition of TTX, Co(2+), or DA. In DA agonists, quinpirole rather than SKF81297 had a more depressive effect on the potential oscillation. These results indicate that the slow hyperpolarization is due to the suppression of noninactivating Na(+)-Ca(2+) conductances via mainly D(2)-like receptors in the medium spiny neurons. In conclusion, the DA actions on the medium spiny neurons show a transient inhibition by the activation of D(1)- and D(2)-like receptors in mainly GABAergic interneurons and a tonic excitation and/or inhibition by the activation of mainly D(1)-like receptors in cholinergic interneurons and by the activation of mainly D(2)-like receptors in the medium spiny neurons, respectively.

Anesthetics, Local↗
PubMed2001

[A case of pemphigus foliaceus associated with bullous impetigo successfully treated with tetracycline and nicotinamide].

A 50-year-old Japanese woman visited our clinic, complaining of generalized erythema with painful erosions and bullae. The histopathological findings of the skin lesion suggested development of impetigo. Gentamycin-resistant Staphylococcus aureus was detected by the bacterial culture examination from the impetiginous bullae. A direct immunofluorescence study of the lesion showed an intercellular deposition of IgG and C3 in the upper epidermis. We diagnosed this case as pemphigus foliaceus associated with bullous impetigo. A combined oral administration of tetracycline (200 mg/day) and nicotinamide (1200 mg/day) for 3 weeks was successful. In Japan, patients with moderate to severe symptoms of pemphigus foliaceus are usually treated with oral steroid therapy. To our knowledge, however, there is no reported pemphigus case which has been successfully treated only with tetracycline and nicotinamide.

Anti-Bacterial Agents↗
PubMed2001

Mechanisms underlying the depression of evoked fast EPSCs following in vitro ischemia in rat hippocampal CA1 neurons.

The mechanisms underlying the depression of evoked fast excitatory postsynaptic currents (EPSCs) following superfusion with medium deprived of oxygen and glucose (in vitro ischemia) for a 4-min period in hippocampal CA1 neurons were investigated in rat brain slices. The amplitude of evoked fast EPSCs decreased by 85 +/- 7% of the control 4 min after the onset of in vitro ischemia. In contrast, the exogenous glutamate-induced inward currents were augmented, while the spontaneous miniature EPSCs obtained in the presence of tetrodotoxin (TTX, 1 microM) did not change in amplitude during in vitro ischemia. In a normoxic medium, a pair of fast EPSCs was elicited by paired-pulse stimulation (40-ms interval), and the amplitude of the second fast EPSC increased to 156 +/- 24% of the first EPSC amplitude. The ratio of paired-pulse facilitation (PPF ratio) increased during in vitro ischemia. Pretreatment of the slices with adenosine 1 (A1) receptor antagonist, 8-cyclopenthyltheophiline (8-CPT) antagonized the depression of the fast EPSCs, in a concentration-dependent manner: in the presence of 8-CPT (1-10 microM), the amplitude of the fast EPSCs decreased by only 20% of the control during in vitro ischemia. In addition, 8-CPT antagonized the enhancement of the PPF ratio during in vitro ischemia. A pair of presynaptic volleys and excitatory postsynaptic field potentials (fEPSPs) were extracellularly recorded in a proximal part of the stratum radiatum in the CA1 region. The PPF ratio for the fEPSPs also increased during in vitro ischemia. On the other hand, the amplitudes of the first and second presynaptic volley, which were abolished by TTX (0.5 microM), did not change during in vitro ischemia. The maximal slope of the Ca(2+)-dependent action potential of the CA3 neurons, which were evoked in the presence of 8-CPT (1 microM), nifedipine (20 microM), TTX (0.5 microM), and tetraethyl ammonium chloride (20 mM), decreased by 12 +/- 6% of the control 4 min after the onset of in vitro ischemia. These results suggest that in vitro ischemia depresses the evoked fast EPSCs mainly via the presynaptic A1 receptors, and the remaining 8-CPT-resistant depression of the fast EPSCs is probably due to a direct inhibition of the Ca(2+) influx to the axon terminals.

Animals↗
PubMed2001

[Interleukin-6 in the cerebrospinal fluid of two patients with herpes zoster meningitis].

Interleukin-6 (IL-6) levels in the cerebrospinal fluid (CSF) and serum were measured in two immuno-competent children with herpes zoster meningitis, who had vesicles, fever, headache and vomiting before admission. The causative agent was identified as varicella zoster virus (VZV) by detecting an increased antibody index in the serum and specific DNA (by polymerase chain reaction) in the CSF. Both patients fully recovered after treatment with acyclovir. The CSF IL-6 levels were high (260.1 pg/ml, 106.1 pg/ml) at the acute stage and thereafter showed a rapid recovery. The serum IL-6 levels were normal. The increased IL-6 level in the CSF may reflect intrathecal inflammatory response following invasion of VZV into the central nervous system.

Adolescent↗
PubMed2001

A case of hemiplegic migraine in childhood: transient unilateral hyperperfusion revealed by perfusion MR imaging and MR angiography.

We report on an 8-year-old girl with a typical attack of hemiplegic migraine, in whom MR angiography and perfusion MR imaging revealed unilateral dilation of branches of both the middle and posterior cerebral arteries and hyperperfusion of the ipsilateral hemisphere, respectively. The findings resolved spontaneously after the attack. These imaging techniques should be indicated for patients with migraine attacks and may play a role in assessing the vascular events in migraine headache.

Cerebrovascular Circulation↗
PubMed2001

[Tracheal intubation without muscle relaxants using propofol and varying doses of fentanyl].

This study was designed to evaluate airway and intubating conditions without muscle relaxants after administration of fentanyl and propofol in 55 patients aged 20-60 years for elective surgery. Patients were randomly assigned to one of four groups to receive fentanyl 0, 2, 3, or 4 micrograms.kg-1, respectively. Three minutes after the administration of fentanyl, propofol (2 mg.kg-1) was given for induction of anesthesia. After the loss of consciousness, laryngoscopy and tracheal intubation, supplemented with topical anesthesia of lidocaine (2 mg.kg-1), were attempted. In control group, without administration of fentanyl, all patients were judged to provide poor intubating conditions. Increasing doses of fentanyl reduced the incidences of movement and persistent coughing on laryngoscopy and intubation in a dose-related manner. However, visualization of the vocal cord was significantly. (P < 0.05) more likely to be impossible in patients in 4 micrograms.kg-1 fentanyl group (40%) compared with patients in 2 micrograms.kg-1 fentanyl group (7%). There were no significant differences among groups receiving fentanyl with respect to vocal cord position. The vocal cords were closed in 26% of patients receiving fentanyl and propofol for intubation. Tracheal intubation without muscle relaxants is not recommended because of the potential unacceptable intubating conditions.

Adult↗
PubMed2001

New approach for the establishment of mouse early embryonic stem cells and induction of their differentiation.

Eleven early embryonic stem (EES) cell lines were established using a new novel method. Two cell stage embryos from the ddY mouse strain were cultured in alpha-MEM supplemented with 10% fetal calf serum (FCS) and embryotrophic factors (ETFs) and allowed to develop to the trilaminal germ disc embryonic stage. Only small round cells (EES cells) were isolated by the colony isolating technique and subsequently cultured in the same medium containing the ETFs and leukemia inhibitory factors (LIF-10 ng/ml). The newly established embryonic stem (ES) cells isolated from inner cell mass of blastocysts differentiated from two cell stage embryo in culture. The EES and ES cell lines were maintained in an undifferentiated state using Ham's F12 medium supplemented with 10% FCS and 1 ng/ml of LIF. The EES cells maintained their normal genetic and morphological features as well as their potential to differentiate into a broad spectrum of cell types as well as their ability to contribute to all cell lineages in chimeric mice. Moreover, these cell lines changed and differentiated into various kinds of cells by removing LIF and by the addition of ETFs to the vitro culture system. All 11 EES cell lines and 3 ES cell lines formed embryoid bodies; however, cell line EES-4 formed tube-like structures which extended, anastomosed with each other, and finally formed networks when the LIF were absent. Primitive germ organ-like structures composed of 3 germ layers were recognized in the cultures following the administration of ETFs. In conclusion, the new method devised by us is a novel, easy and reliable technique for establishing EES cell lines.

Animals↗
PubMed2000

Subcutaneous panniculitis by Epstein-Barr virus-infected natural killer (NK) cell proliferation terminating in aggressive subcutaneous NK cell lymphoma.

We describe here a case involving a patient presenting initially with subcutaneous panniculitis, which developed after 12 years into aggressive subcutaneous natural killer (NK) cell lymphoma with peripheral blood involvement and hemophagocytosis. The surface marker of lymphoid cells in peripheral blood was CD2+3-7+8-16+56+. Skin biopsies were taken in May 1986 and June 1998. The initial biopsy revealed a diffuse proliferation of atypical lymphoid cells in the subcutaneous tissue with panniculitis, while the second biopsy revealed the presence of large lymphoid cells in the subcutaneous tissue with necrotic changes, consistent with a diagnosis of malignant lymphoma (diffuse pleomorphic type). The lymphoid cells from these two specimens were positive for CD56 and such cytotoxic molecules as T-cell intracellular antigen-1 (TIA-1), granzyme B, and, interestingly, also positive for Epstein-Barr (EB) virus by in situ hybridization. This suggests that chronic EB virus infections play an important role in the early stages of tumorigenesis and in the progression of NK cell lymphoproliferative disorders.

Adaptor Proteins, Signal Transducing↗