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Biomedical subjects

S Ishida

Publications and source records attributed to S Ishida.

At least 145 records · Page 8Linked to original sources
PubMed1995

Serial MRI in early Creutzfeldt-Jacob disease with a point mutation of prion protein at codon 180.

We report a 66-year-old woman with histologically diagnosed Creutzfeldt-Jacob disease (CJD), followed with MRI from an early clinical stage. MRI demonstrated expansion of the high cortical signal on T2-weighted images, which differs from previous MRI reports of CJD. This patient followed an atypical clinical course: 16 months had passed before she developed akinetic mutism, and periodic sharp waves had not been detected on EEG after 2 years in spite of her akinetic mutism. Brain biopsy showed primary spongiform changes in the grey matter, and a point mutation of the prion protein gene at codon 180 was discovered using polymerase chain reaction direct sequencing and Tth 111 I cutting. This is the first case with the point mutation of the codon 180 variant with an atypical clinical course and characteristic MRI findings.

Aged↗
PubMed1995

Characterization of cis-regulatory elements of the c-myc promoter responding to human GM-CSF or mouse interleukin 3 in mouse proB cell line BA/F3 cells expressing the human GM-CSF receptor.

Interleukin 3 (IL-3) or granulocyte macrophage colony-stimulating factor (GM-CSF) activates c-fos, c-jun, and c-myc genes and proliferation in both hematopoietic and nonhematopoietic cells. Using a series of deletion mutants of the beta subunit of human GM-CSF receptor (hGMR) and inhibitors of tyrosine kinase, two distinct signaling pathways, one for activation of c-fos and c-jun genes, and the other for cell proliferation and activation of c-myc gene have been elucidated. In contrast to wealth of information on the pathway leading to activation of c-fos/c-jun genes, knowledge of the latter is scanty. To clarify the mechanisms of activation of c-myc gene by cytokines, we established a transient transfection assay in mouse proB cell line BA/F3 cells expressing hGMR. Analyses of hGMR beta subunit mutants revealed two cytoplasmic regions involved in activation of the c-myc promoter, one is essential and the other is dispensable but enhances the activity. These regions are located at the membrane proximal and the distal regions covering amino acid positions 455-544 and 544-589, respectively. Characterization of cis-acting regulatory elements of the c-myc gene showed that the region containing the P2 promoter initiation site is sufficient to mediate the response to mIL-3 or hGM-CSF. Electrophoretic mobility shift assay using an oligonucleotide corresponding to the distal putative E2F binding site revealed that p107/E2F complex, the negative regulator of E2F, decreased, and free E2F increased after mIL-3 stimulation. These results support the thesis that mIL-3 or hGM-CSF regulates the c-myc promoter by altering composition of the E2F complexes at E2F binding site.

Animals↗
PubMed1995

Electrophysiological effects of SD-3212, a novel antiarrhythmic agent, on rabbit hearts in vivo and in vitro.

We examined the electrophysiological effects of SD-3212, a novel antiarrhythmic agent in rabbits in in vivo and in vitro experiments. During in vivo experiments, monophasic action potentials (MAPs) of the left ventricular endocardium were simultaneously recorded with surface ECG and arterial blood pressure (BP). Under constant atrial pacing, SD-3212 (0.1, 0.2, and 0.3 mg/kg/min) was continuously infused in rabbits for 20 min. SD-3212 > or = 0.2 mg/kg/min prolonged PQ interval, QRS duration, and MAP duration, and decreased arterial BP dose dependently. During in vitro experiments, transmembrane APs were recorded from the isolated papillary muscles by a microelectrode technique. SD-3212 (3 x 10(-6)-10(-5) M) prolonged the AP duration (APD) and decreased the maximum upstroke velocity of the AP (Vmax) in a concentration-dependent manner without affecting the amplitude of AP or resting potential. The inhibitory action of SD-3212 on Vmax was enhanced as the stimulation frequency was increased, whereas the prolongation of APD did not vary with stimulation frequency. The results suggest that SD-3212 has an inhibitory action on some outward currents as well as sodium and calcium currents.

Action Potentials↗
PubMed1995

Evaluation of soluble IL-6 receptor concentration in serum and epithelial lining fluid from patients with interstitial lung diseases.

We measured soluble IL-6 receptor (sIL-6R) levels in serum and bronchoalveolar lavage fluids (BALF) from patients with interstitial pneumonia of unknown etiology (IP) (n = 17), sarcoidosis (n = 8) and normal control subjects (n = 10), to investigate its role in pulmonary diseases. Soluble IL-6R was determined by an ELISA. The volume of epithelial lining fluid (ELF) in BALF was estimated using an urea method. We found that levels of sIL-6R in serum, BALF, and ELF from patients with IP or sarcoidosis were significantly higher than those from normal subjects. Furthermore, levels of sIL-6R in BALF or ELF were significantly correlated with those of albumin, indicating that sIL-6R, together with albumin, may enter ELF as a result of the increased permeability caused by pulmonary inflammation. Thus most of the sIL-6R in ELF would be from serum, and relatively small amounts of it might be produced locally. However, sIL-6R levels in ELF, but neither serum nor BALF, were significantly correlated with levels of C-reactive protein in patients with IP. These results suggest that both systemic and local production of sIL-6R are increased, and raised sIL-6R is involved in the modulation of systemic and local inflammatory responses in patients with IP and sarcoidosis.

Adult↗
PubMed1995

Prognosis of epilepsy withdrawn from antiepileptic drugs.

Antiepileptic drugs (AED) were discontinued in 55 epileptics who had been free from seizures treated with AED, in accordance with the following criteria and procedures. (i) A reduction in AED commences when patients have been free from seizures for at least 2 years and epileptic discharges have also disappeared in repeated electroencephalogram (EEG) recordings during that period. (ii) AED are gradually reduced if no relapse is seen in clinical seizures and epileptic discharges in EEG. (iii) As a rule at least 2 years are required as the interval from the onset of a reduction to the withdrawal of AED. Forty-three patients were followed up by a questionnaire and/or by telephone and the follow-up period from the withdrawal of AED to the survey ranged from 0.9 to 8.8 years; in 38 patients (88.4%) the period was longer than 2 years. No relapse of seizures was found in any of the 43 patients. The severity of epilepsy judged by the total number of frequency of seizures, the presence of neuropsychiatric complications, the combination of different types of seizures, and the duration of epilepsy from the seizure onset to the last seizure appeared not to be risk factors for the recurrence of seizure. Normal EEG was, however, considered to be an important prerequisite for a good prognosis.

Adolescent↗
PubMed1995

Neuroepidemiological study of childhood epilepsy by application of international classification of epilepsies and epileptic syndromes (ILAE, 1989).

A population-based survey of childhood epilepsy was made in 1975 on the total population of children aged < 10 years living in Okayama Prefecture (n = 2,378 patients). Using the data obtained, we attempted to reclassify the various types of epilepsy according to the international classification (ILAE, 1989). Reclassification was possible in 1,872 (78.7%) of the 2,378 cases. The 1,872 cases consisted of 1,045 (55.8%) with localization-related epilepsies, 824 (44.0%) with generalized epilepsies, and 3 (0.2%) with epilepsies undetermined whether focal or generalized. Classification of the epilepsies in a population-based survey using the international classification involves difficulties, because both clinical and EEG findings are essential. However, if an appropriate area is selected, classification of epilepsies and epileptic syndromes in a population-based survey is possible by referring to all medical records stored at every hospital and practitioner's clinic that administers treatment to patients with epilepsy in the area.

Age Factors↗
PubMed1995

NP-06: a novel anti-human immunodeficiency virus polypeptide produced by a Streptomyces species.

From an extract of a Streptomyces culture, we identified and purified a novel compound, NP-06, which is active against human immunodeficiency virus (HIV) in vitro. Analyses indicate that NP-06 is a hydrophobic 21-mer oligopeptide, N terminally cyclized through the side chain of Asp-9, containing two intramolecular cystine linkages with a molecular weight of 2,163.4. The 50% inhibitory concentrations were 2.8 and 1.3 microM when NP-06 was tested for in vitro anti-HIV-1 activity in ATH8 cells and phytohemagglutinin-activated peripheral blood mononuclear cells, respectively, NP-06 appears to block the early stage of HIV-1 infection, most likely at the stage of virus-cell fusion.

Amino Acid Sequence↗
PubMed1995

Relation between QT and RR intervals in patients with bradyarrhythmias.

OBJECTIVE: To investigate the relation between QT and RR intervals in the sick sinus syndrome or high degree atrioventricular block. PATIENTS: 32 patients with episodes of prolonged RR intervals (> or = 2.6 s) on Holter electrocardiographic recordings. DESIGN: QT and RR intervals were measured manually every 100 to 150 beats on electrocardiographic strips reprinted from the Holter tape over 24 hours. The slope of the QT/RR relation was determined by the linear regression equation for RR intervals < or = 1.4 s (slope 1) and > 1.4 s (slope 2). RESULTS: Slope 2 (0.0068 (0.0030)) was significantly lower than slope 1 (0.0824 (0.0059), P < 0.0001) in the overall patient population. Slopes 1 and 2 were significantly lower (P < 0.001) in the 23 patients with QT intervals at the preceding RR interval of 1 s (QT1s) of < 0.44 s (0.0692 (0.0053) and 0.0019 (0.0030), respectively) than in the nine patients with QT1s intervals > or = 0.44 s (0.1159 (0.0091) and 0.0194 (0.0055), respectively). Slopes 1 and 2 correlated positively with QT1s interval in all patients. CONCLUSIONS: The QT/RR relation was comparatively flat when the RR interval was prolonged. Patients with prolonged QT intervals showed exaggerated prolongation of the QT interval with prolonged cycle lengths when compared with patients with normal QT intervals.

Adolescent↗
PubMed1995

Circulating interleukin-6 levels in patients with bronchial asthma.

Circulating interleukin-6 (IL-6) levels were determined using a sensitive enzyme immunoassay in adults with asthma in stable condition during naturally occurring attacks and before and after allergen inhalation tests. IL-6 was significantly elevated even in asymptomatic asthmatic subjects (n = 17) compared with normal control subjects (n = 17). During naturally occurring asthmatic attacks, serum IL-6 levels were significantly elevated in comparison with those in a symptom-free condition (4 wk interval; n = 8, p < 0.01). No significant difference was observed in serum IL-6 levels obtained from control asymptomatic asthmatic subjects during the period (n = 10). There was a significant elevation in circulating IL-6 levels in eight asthmatic patients following inhalation of allergen but not methacholine. These results suggest that IL-6 is involved in the pathophysiology of bronchial asthma.

Adult↗
PubMed1995

Big insulin-like growth factor II-producing hepatocellular carcinoma associated with hypoglycemia.

A 76-year-old female with a hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) was hospitalized because of fasting hypoglycemia. Her sera contained a low concentration of immunoreactive insulin and insulin-like growth factor (IGF)-I, while the IGF-II level was normal. However, most of the IGF-II consisted of the high molecular weight form (big IGF-II). The tumor tissue contained fetal type of IGF-II mRNA (6.0 kb). Furthermore, we found that one of the four patients examined with HCV-related HCC had big IGF-II in serum. This indicates that non-islet cell tumor hypoglycemia (NICTH) in HCV-related HCC might be accompanied by production of big IGF-II by the tumor.

Aged↗
PubMed1995

Induction of IgE antibody production in mice with different DPT-vaccine preparations.

Antibody production in mice after immunization with diphtheria-pertussis-tetanus (DPT) vaccine was investigated. Six lots of the vaccine produced in the same year by six manufacturers in Japan were chosen. Production of IgE antibody specific to either diphtheria or tetanus toxoid varied among vaccine preparations used, although there was no apparent difference in IgG antibody production after immunization. In addition, the level of IgE antibody specific to diphtheria toxoid was correlated with that of IgG1 antibody and inversely with that of IgG2 antibody. These results suggest that each vaccine preparation may induce a distinct pattern of antibody production and, therefore, the type of immune response induced by vaccination may vary among vaccine preparations.

Animals↗
PubMed1995

[Seven cases of pseudoseizure unnecessarily treated with AEDs].

An increasing number of pseudoseizures and/or behavioral abnormalities are being unnecessarily treated with anti-epileptic drugs (AEDs) for long periods, often producing adverse effects and even aggravating abnormal behaviors. Seven of the 77 new referrals (43 men, 34 women) to our epilepsy clinic within a single year (1992-1993) were misdiagnosed with epilepsy and had pseudoseizures or behavioral abnormalities alone. The initial episodes for which AEDs had been given were febrile convulsions during childhood in two patients, nonfebrile convulsions of uncertain nature in four patients, and learning difficulty with EEG abnormality in one patient. The reasons AED treatment had continued for so long are probably the persistence of behavioral problems and/or EEG abnormalities and failure to reevaluate the patients to determine whether they had true epileptic symptomatology. Based on the results of this study, we concluded that: 1. AED treatment should be initiated only after a suspicious episode had been demonstrated to be truly epileptic in nature. 2. The diagnosis of pseudoseizures should be made on the basis of careful investigation of clinical symptomatology and ictal pattern as described in "Proposed International Classification of Clinical and Electroencephalographic Epileptic Seizures, 1981". 3. In doubtful cases, frequent reevaluation of the nature of the episodes and the necessity of AEDs is needed to avoid adverse effects.

Adolescent↗
PubMed1995

A direct role of transcription factor E2F in c-myc gene expression during granulocytic and macrophage-like differentiation of HL60 cells.

The transcription factor E2F is known to play an important role in cell cycle progression through interaction with retinoblastoma protein. HL60 cells are able to differentiate into a granulocytic lineage by prolonged exposure to retinoids and into a macrophage-like lineage by exposure to tumor promoter 12-O-tetradecanoylphorbol 13-acetate, with a rapid decrease of c-myc gene expression. In this study, we assessed the changes of the E2F-binding pattern to the P2 promoter region of the c-myc gene during differentiation into both lineages. The observed changes of the E2F-binding pattern were a decrease of free E2F and an appearance of retinoblastoma protein-containing E2F complexes in both lineages. The effects of the anti-c-myc antibody and the recombinant c-Myc protein on the E2F-binding patterns suggest that the c-Myc protein is not involved directly in these changes. These changes also led the suppression of transcriptional initiation from the P2 promoter. The results indicate that, in the course of HL60 cell differentiation, E2F plays a direct role in the transcriptional control of the c-myc gene through interaction with the retinoblastoma protein. A potential role for the c-Myc protein is discussed in relation to an existing state of E2F and E2F-RB complexes in the HL60 cells.

Base Sequence↗
PubMed1995

Study of JA300 as agent having high transglycosylation activity.

Escherichia coli JA300 as the strain catalyzing transglycosylation of nucleic acids has so strong activity. We scrutinized where the high faculty of this strain come from. Using PCR methods with our primer pair MI-1 (up; GTT GAA TTC GCC TTT GTT ATG TCA C) and MI-2 (down; GTT CCG CTA ACG GAA CAC CTA GGC CT), we isolated deoD (the coding region of PNPase) of JA300. Nucleotide sequence analysis indicated that deoD of JA300 is definitely same as that of parent strain K12. The fact that the transcription of deoD of JA300 is more active than that of K12 was also revealed after the analysis by Northrn blot hybridization. These data may suggest that the varieties of gene concerning regulation contribute to the difference of PNPase activity between them.

Base Sequence↗