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Biomedical subjects

S Ishida

Publications and source records attributed to S Ishida.

At least 109 records · Page 6Linked to original sources
PubMed1998

The genomic breakpoint and chimeric transcripts in the EWSR1-ETV4/E1AF gene fusion in Ewing sarcoma.

Chromosome translocation creates a fusion between the EWSR1 gene and an ETS family gene. The fusion between these two genes is a characteristic feature of Ewing sarcoma. We previously identified a fourth translocation, t(17;22)(q12;q12), in genomic DNA isolated from cells of patients affected with Ewing sarcoma. The discovery of this translocation suggested that there might be a novel EWSR1-ETV4 fusion gene. In the present study, we determined the genomic breakpoint and characterized the chimeric transcript of the EWSR1-ETV4 fusion gene in two t(17;22) Ewing sarcomas. Reverse transcriptase-PCR assay showed an in-frame fusion between the 5'-terminal region of EWSR1 and the 3' end of ETV4 (alias E1AF, PEA3); the chimeric transcript could thus serve as a template for expression of a protein composed of the N-terminal portion of EWSR1 fused to the DNA-binding domain of ETV4. Long PCR and sequence analysis of genomic DNA revealed that either exon 8 or intron 7 of EWSR1 is fused to the same intron of ETV4 in both tumors. Several palindromic oligomer sequences were found close to the breakpoints in both genes. The 159-bp Alu-like sequence was repeated in the breakpoint region of the ETV4 gene. These observations suggest a mechanism of EWSR1-ETV4 gene fusion.

Alu Elements↗
PubMed1998

A pilot study of dehydroepiandrosterone sulfate in myotonic dystrophy.

We studied the effect of i.v. administration of a dehydroepiandrosterone sulfate (DHEAS) preparation (200 mg/day for 8 weeks) in 11 patients with myotonic dystrophy (MyD). After DHEAS, activities of daily living improved, muscle strength increased, and myotonia decreased. Conduction block and premature beats also improved in the four patients with cardiac involvement. This pilot study may provide a rationale for a controlled study of DHEAS in MyD.

Activities of Daily Living↗
PubMed1998

Genetic analysis enables definite and rapid diagnosis of cerebrotendinous xanthomatosis.

Mutations in the sterol 27-hydroxylase gene (CYP27) cause cerebrotendinous xanthomatosis (CTX). Early diagnosis of CTX is crucial because treatment with chenodeoxycholic acid can prevent or reverse some of the neurologic disability associated with the disease. We report the identification of three types of mutations (Arg441Trp, Arg372Gln, and Arg441Gln) in the CYP27 gene in five patients with suspected CTX from four unrelated families by restriction endonuclease analysis.

Adult↗
PubMed1998

Dynamics of QT interval in a patient with long QT syndrome and a normal QT interval.

A case report of a 15-year-old girl who experienced syncope and torsades de pointes is presented. The girl had a normal QT interval (QTc=0.37 sec) on the resting electrocardiogram (ECG). Infusion of isoproterenol induced QT prolongation (QTc=0.62 sec) and frequent occurrence of multiform ventricular premature beats. Her Holter ECG showed a prolongation of the QTc interval with a shortening of the RR interval. Low-frequency power (LF) and high-frequency power (HF) of heart rate variability were evaluated from the Holter ECG. The patient showed a statistically significant negative QTc/HF and a significant positive QTc/(LF/HF) relationship, whereas none of the age- and sex-matched healthy subjects showed these relationships. The slope of the QT/RR relationship for the patient was below the lower limit of the normal range. This report describes the unusual relationship of QT interval to RR interval and heart rate variability in a long QT syndrome patient with a normal QT interval on resting ECG.

Adolescent↗
PubMed1998

Postrest shortening of the action potential duration in rabbits: in vitro and in vivo correlation.

Previous evidence has shown that the action potential duration of rabbit ventricular muscle cells shortens after a rest period (postrest shortening). However, there has not been much research on postrest shortening in the intact heart. We recorded transmembrane action potentials (TAPs) of isolated papillary muscle from rabbit ventricle with glass microelectrodes and monophasic action potentials (MAPs) of the rabbit left ventricular endocardium with contact electrodes. In the in vitro experiments, repetitive regular stimuli (S1) at a cycle length of 1 sec were followed by a single extrastimulus (S2) at coupling intervals (S1S2) ranging between 0.5 sec and 8 sec. The increase in the S1S2 interval resulted in a progressive shortening of the duration of TAP elicited by the S2, which was abolished by the simultaneous application of 1 mmol/L 4-aminopyridine and 2 micromol/L ryanodine. In the in vivo experiments, regular right ventricular pacing (S1) at a cycle length of 0.35 sec was followed by a single extrastimulus (S2) with coupling intervals (S1S2) ranging between 0.25 sec and 3 sec. The increase in the S1S2 interval also resulted in a progressive shortening of the duration of MAP elicited by the S2. This is the first report to demonstrate postrest shortening in the intact heart, which probably occurs because of a mechanism analogous to that observed in the isolated ventricular muscle.

4-Aminopyridine↗
PubMed1998

Signal-averaged electrocardiogram shows a heart rate dependent diurnal variation in healthy subjects.

It has not been determined if signal-averaged electrocardiograms (SAECGs) have a diurnal variation. We recorded 3-channel 24-hour ECGs in 30 healthy volunteers and calculated the following parameters for the first 500 sec of every hour over the 24-hour period: the mean heart rate, the filtered QRS duration (f-QRS), the root-mean-square voltage of the signals in the last 40 msec of the QRS (RMS40), and the duration of low-amplitude signals (< 40 microV) in the terminal portion of the QRS (LAS40). Heart rate and RMS40 increased in the daytime compared with the nighttime; f-QRS and LAS40 increased during the nighttime hours. The f-QRS and LAS40 were negatively correlated with heart rate in all and 22 (73%) of 30 subjects, respectively, and RMS40 was positively correlated with heart rate in 21 subjects (70%). In conclusion, SAECGs exhibit a clear diurnal variation in healthy subjects, which is closely related to changes in heart rate.

Adult↗
PubMed1998

A case of hemolytic uremic syndrome associated with emphysematous cholecystitis and a liver abscess.

Hemolytic uremic syndrome (HUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. Most cases of HUS are characterized by a prodromal phase of diarrhea and melena, and affect mainly children. Here we report a unique case of adult-onset HUS that was associated with emphysematous cholecystitis and a liver abscess. The patient did not suffer from diarrhea or melena on admission, but abdominal CT scans revealed emphysematous cholecystitis and a liver abscess. Cholecystectomy was performed and the liver abscess was drained. Cultures of the bile and liver abscess contents were negative, but the serum samples had antibodies against Escherichia coli (E. coli) O157. The patient was anuric for 14 days, and underwent hemodialysis that was repeated 15 times and plasma exchanges 6 times. She recovered from acute renal failure but with inadequate urinary concentrating ability as a sequela. Histopathological examination of renal biopsy specimens on the 83rd hospital day revealed almost normal glomeruli and patchy atrophy of tubules with an increase of interstitium. This is a very rare case of HUS associated with emphysematous cholecystitis and a liver abscess successfully treated with aggressive supportive care. It is possible that an infection with verotoxin-producing E. coli O157 caused the disease.

Aged↗
PubMed1998

[Acute renal failure in non-fulminant acute hepatitis without hepatitis A, B or C virus infection].

Here, we report a 35-year-old man with non-fulminant acute non A, non B, non C hepatitis which developed into acute renal failure. The patient was admitted to hospital with the chief complaints of general fatigue, nausea and a high-grade fever of 40 degrees C. Laboratory examination revealed severe liver dysfunction and renal insufficiency on admission: his serum glutamic oxaloacetic transaminase was 3.203 IU/ml, serum glutamic pyruvic transaminase was 3.825 IU/ml, lactic dehydrogenase was 2.840 IU/ml, blood urea nitrogen was 65 mg/dl, and creatinine was 7.6 mg/dl. Hemodialysis was conducted during the initial 19-day period after admission because anuria was manifested on admission. On the 36th day after onset, renal functions returned to normal and the patient was negative for IgM-HA antibody. HBs antigen, IgM-HBC antibody, HCV antibody, cytomegalovirus antibody, and Epstein-Barr virus antibody. However, liver biopsy for histological examination on the 44th day after onset revealed no specific findings except the healing stage of acute hepatitis. Renal biopsy on the 49th day showed the healing stage of acute tubular necrosis without any glomerular change. It has been infrequently reported that acute renal failure develops following a non-fulminant acute state without hepatitis A, B or C virus infection. It is necessary to take acute renal failure into account in the clinical course of non-fulminant non A, non B, non C hepatitis.

Acute Disease↗
PubMed1998

[Aqueous levels of eosinophil cationic protein and major basic protein in patients with retinal detachment associated with atopic dermatitis].

We measured the aqueous levels of eosinophil cationic protein (ECP) and major basic protein (MBP) to investigate a possible relationship between cytotoxic eosinophil granule proteins and retinal detachment (RD) in patients with atopic dermatitis. While aqueous ECP was detected in only 1 of 15 cases of RD associated with atopic dermatitis, aqueous MBP was detected in 6 of 14 cases (42.9%). 11 cases of RD without atopic dermatitis were also studied, but neither ECP nor MBP was detected. Although the role of aqueous ECP and MBP was not elucidated, the results indicate that cytotoxic eosinophil granule proteins, especially MBP, are present in aqueous humor in certain cases of RD associated with atopic dermatitis.

Adolescent↗
PubMed1997

Transcriptional activation of the human c-myc gene by simian virus 40 large T antigen without binding to p53 and RB proteins in the transient expression system.

Transcriptional activation of the human c-myc gene by SV40 large T antigen was examined using HepG2 cells by co-transfecting a T antigen expression plasmid with a myc-CAT construct containing the 2.3-kb upstream region from the P1 promoter and the P2 promoter region fused to the CAT gene. T antigen increased the basal activity of the P2 promoter region containing the E2F binding site, but both the P2 promoter region and the upstream region from the P1 promoter were important for overall activation by T antigen. CAT assay using mutated T antigen lacking p53 or the RB binding site indicated that p53 or RB was not mainly involved in transcriptional activation of the c-myc gene. It appears that activation of the c-myc gene by T antigen is probably dependent upon E2F and a cellular factor through a mechanism which is independent of binding of T antigen to p53 and RB.

Antigens, Polyomavirus Transforming↗
PubMed1997

In vivo electron spin resonance analysis of nitroxide radicals injected into a rat by a flexible surface-coil-type resonator as an endoscope- or a stethoscope-like device.

The flexible surface-coil-type resonator (FSCR) operating in a 700 MHz microwave electron spin resonance (ESR) system was applied to measure the nitroxide radicals at a specific area in rats. The FSCR was composed of a single-turn coil with a diameter of 5 mm and two flexible coaxial lines of 450 mm in length. For an endoscope-like application, the FSCR was inserted into the rectum of the rat and sequential changes in the ESR signals of the intravenously injected nitroxide radical (4-hydroxy-2,2,6,6-tetramethyl-piperidine-1-oxyl; TEMPOL or 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy; carbamoyl-PROXYL) were measured. The ESR signal intensity of the nitroxide decreased according to first-order kinetics. For a stethoscope-like application, the FSCR was placed at several sites on the abdominal skin of the rats receiving a subcutaneous injection of carbamoyl-PROXYL, and diffusion and/or metabolism of the radical in the skin was observed.

Animals↗
PubMed1997

Evaluation of left ventricular wall motion and function in patients with previous myocardial infarction by three-dimensional 99mTc-HSAD multigated cardiac pool imaging.

To evaluate left ventricular (LV) wall motion stereoscopically from all directions and to calculate the LV volume by three-dimensional (3D) imaging. 99mTc-DTPA human serum albumin-multigated cardiac pool-single photon emission computed tomography (99mTc-MUGA-SPECT) was performed. A new data processing program was developed with the Application Visualization System-Medical Viewer (AVS-MV) based on images obtained from 99mTc-MUGA-SPECT. In patients with previous myocardial infarction, LV function and LV wall motion were evaluated by 3D-99mTc-MUGA imaging. The LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were obtained from 3D-99mTc-MUGA images by the surface rendering method, and the left ventricular ejection fraction (LVEF) was calculated at thresholds of 35% (T1), 40% (T2), 45% (T3), and 50% (T4). There was a strong correlation between the LV volume calculated by 3D-99mTc-MUGA imaging at a threshold of 40% and that determined by contrast left ventriculography (LVEDV: 194.7 +/- 36.0 ml vs. 198.7 +/- 39.1 ml, r = 0.791, p < 0.001; LVESV: 91.6 +/- 44.5 ml vs. 93.3 +/- 41.3 ml, r = 0.953, p < 0.001), respectively. When compared with the LVEF data obtained by left ventriculography, significant correlations were found for 3D images reconstructed at each threshold (T1: r = 0.966; T2: r = 0.962; T3: r = 0.958; and T4: r = 0.955). In addition, when LV wall motion obtained by 3D-99mTc-MUGA imaging (LAT and LAO views) was compared with the results obtained by left ventriculography (RAO and LAO views), there was good agreement. 3D-99mTc-MUGA imaging was superior in allowing evaluation of LV wall motion in all directions and in assessment of LV function, since data acquisition and image reconstruction could be done within a short time with the three-detector imaging system and AVS-MV. This method appears to be very useful for the observation of both LV wall motion and LV function in patients with ischemic heart disease, because it is a noninvasive examination.

Adult↗
PubMed1997

Circadian variation of QT interval dispersion: correlation with heart rate variability.

The circadian variation of QT interval dispersion and its correlation with heart rate variability (HRV) was examined in 17 normal subjects by using 24-hour recordings of three-lead electrocardiograms. Measurements of HRV, R-R intervals, and QT intervals were made for the first 6 minutes of each hour over a 24-hour period. Spectral analysis of HRV yielded low-frequency power (LF) (0.04-0.15 Hz), high-frequency power (HF) (0.15-0.40 Hz), and the ratio of LF to HF (LF/HF). A rate-corrected QT interval (QTc) was calculated by Bazett's formula, and QT and QTc dispersion was defined as the difference between the maximum and minimum values in any two leads. High-frequency power and QT interval were greater at night than during the day: conversely, LF/HF and dispersion of QT and QTc were greater during the day. The QTc interval remained virtually unchanged throughout the 24-hour period. The dispersion of QTc showed a significant negative correlation with HF and a significant positive correlation with LF/HF. The results suggest that an increased sympathetic tone or a decreased vagal tone increases QT dispersion in healthy subjects.

Adult↗
PubMed1997

Two forms of hemitonic seizure in patients with infantile hemiplegia and epilepsy.

Two forms of unilateral tonic (hemitonic) seizure were observed in two adult epileptic patients with infantile hemiplegia. Their ictal EEGs showed diffuse bilaterally synchronous spike bursts without focal features. In one case, a 31-year-old male, the VTR/EEG recording clearly demonstrated hemitonic seizure which simultaneously involved his paretic limbs and body and were associated with loss of consciousness and autonomic signs. In the other case, a 33-year-old male, partial seizures with secondary unilateral generalization were demonstrated by VTR/EEG recording. The reason why these cases do not exhibit motor seizure activity on the unaffected side despite diffuse bilateral EEG changes, a lower motor threshold in the paretic limbs and inhibitory effect in the brain-stem on undamaged side are postulated. These two cases suggest that hemitonic seizures include heterogeneous characteristics of partial and generalized epilepsy. In patients with diffuse brain damage, such as those with infantile hemiplegia, seizures appear to exhibit complicated patterns, with characteristics of partial and generalized seizures. There is a gradiation of expression of unilateral seizure, range from clearly partial seizures to those with mostly features of generalized seizures, except for an asymmetry of motor expression.

Adult↗
PubMed1997

Rare occurrence of ras and p53 gene mutations in mouse stomach tumors induced by N-methyl-N-nitrosourea.

The incidence of point mutations of H-, K- and N-ras and p53 oncogenes in male BALB/c mouse stomach tumors induced with N-methyl-N-nitrosourea (MNU) was examined by direct sequencing and PCR single-strand conformation polymorphism (PCR-SSCP). A mutation of GGT to AGT at K-ras codon 12 was found by SSCP in one adenocarcinoma from a total of 19 specimens including 5 adenocarcinomas, 9 adenomatous hyperplastic regions, 1 squamous cell carcinoma and 4 normal-like stomach regions from 4 mice. No mutations were detected by direct sequencing of H-, K- and N-ras oncogenes at exons 1 (codons 12 and 13) and 2 (codon 61) in a total of 26 specimens comprising 10 adenocarcinomas, 10 adenomatous hyperplastic regions, 2 squamous cell carcinomas and 4 normal-like stomach regions from 6 mice. No mutations were detected by direct sequencing of p53 oncogene at exons 5, 6, 7 and 8 in a total of 30 specimens including 13 adenocarcinomas, 8 adenomatous hyperplastic regions, 2 squamous cell carcinomas, 1 papilloma and 6 normal-like stomach regions from 7 mice. These results suggest that ras and p53 oncogenes do not play a role in mouse stomach carcinogenesis induced by MNU.

Adenoma↗
PubMed1997

[4-year clinico-statistical observation of outpatients].

Clinico-statistical observations were made on the outpatients visiting the Department of Initial Diagnosis and Emergency, Faculty of Dentistry Hospital, Tokyo Medical and Dental University in 1986, 1987, 1989 and 1990. The following findings were obtained according to sex, age group, and chief complaints of new outpatients. Approximately 60% of the outpatients were female during the year examined. The number of outpatients tended to increase in March and to decrease during the winter. The largest number of new outpatients visiting the hospital was in the 20-24-year-old group in both males and females. In the female patients, the 50-54-year-old group had a relatively higher peak. The greatest chief complaint was tooth pain. Further, the chief complaint involving oral soft tissues was due to inflammation. The main disease diagnosed due to chief complaints was caries in the 20-29-year-old group, marginal periodontitis in the 50-59, pericoronitis of wisdom tooth in the 20-29, temporomandibular joint problem in the < or = 19 and masticatory disturbance in the 60 < or = -year-old groups.

Adult↗