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T Yaginuma

Publications and source records attributed to T Yaginuma.

At least 19 recordsLinked to original sources
PubMed1996

Trehalase in the spermatophore from the bean-shaped accessory gland of the male mealworm beetle, Tenebrio molitor: purification, kinetic properties and localization of the enzyme.

Trehalase from the bean-shaped accessory glands of the male mealworm beetle, Tenebrio molitor, was purified by acid treatment, with subsequent chromatography on columns of DEAE-cellulofine and Sephacryl S-300. The molecular masses of the native and the denatured forms were estimated to be 43 and 62 kDa by gel filtration and SDS-PAGE, respectively, an indication that the trehalase may be composed of a single polypeptide. The optimum pH of the reaction catalyzed by trehalase was 5.6-5.8. The Km for trehalose was 4.4 mmol.1(-1). Immunohistochemical experiments with trehalase-specific antiserum showed that the enzyme was localized in one specific type of secretory cell in the bean-shaped accessory gland epithelium and within the semisolid secretory mass that was a precursor to the wall of spermatophore. SDS-PAGE and immunoblotting analysis revealed the presence of a polypeptide of about 62 kDa in the spermatophore. Immunohistochemical observations showed that the trehalase was located at the outgrowth in the anterior portion of the spermatophore. When a fresh spermatophore was immersed in phosphate-buffered saline it discharged sperm in the same manner as in the bursa copulatrix of the female. Before the rupture of the expanded bulb of the spermatophore, almost all of the trehalase had dissolved in the phosphate-buffered saline. The addition of validoxylamine A to the saline, a specific inhibitor of trehalase, did not affect the expansion and evacuation of the spermatophore. These results demonstrate that trehalase, synthesized by a specific type of secretory cell in the bean-shaped accessory gland epithelium, is actively passed into the lumen of the bean-shaped accessory gland and then incorporated into the spermatophore. Trehalase appears to be one of the structural proteins of the spermatophore, although the possibility can not yet be completely ruled out that the trehalase-trehalose system functions for the nourishment and/or activation of the sperm in the bursa copulatrix of the female.

Acetates↗
PubMed1996

Structure of the Bombyx sorbitol dehydrogenase gene: a possible alternative use of the promoter.

In an initial effort to understand the molecular mechanism of how low temperature induces sorbitol dehydrogenase gene expression in diapause eggs of the silkworm, the sorbitol dehydrogenase gene was isolated from a Bombyx genomic library using a cDNA encoding the Bombyx homologue of mammalian sorbitol dehydrogenase as a probe. The gene extended for about 10 kb, consisting of eight exons and seven introns. Four TATA motifs were found in the 5' upstream region of the gene, without CCAAT. AATTAA, instead of AATAAA, was localized in the upstream region of the polyadenylation site. Although a single copy of this gene was present per haploid genome, 1.2 kb and 1.1 kb transcripts were found from yolk cells in diapause eggs and from larval fat-body cells, respectively. The two major transcription initiation sites corresponding to both transcripts were localized at 355 and 226 base pairs upstream from the transition start site, indicating an alternative use of promoter. The 5'-upstream region of the gene contained a consensus sequence, TGA(A/T)AA(A/G/T), that has been found in insect genes expressed mainly in larval and pupal fat bodies. It also contained three kinds of sequences similar to cis-elements recognized by members of the steroid receptor superfamily, such as chicken ovalbumin upstream promoter transcription factor (COUP-TF)/Drosophila Seven up (SVP), Drosophila hormone receptor 39 (DHR39) and Bombyx fushi tarazu transcriptional factor 1 (BmFTZ-F1).

Alternative Splicing↗
PubMed1996

[A case of crescentic glomerulonephritis with extensive hematuria resulting in severe anemia].

A 24-year-old woman was admitted to our hospital because of macroscopic hematuria with clotting. She had been well until two months before admission, when she experienced fever, arthralgia and lethargy and entered another hospital. Laboratory tests showed macroscopic hema-turia, anemia and mild renal dysfunction. Two weeks prior to admission, she had experienced an episode of macroscopic hematuria with clotting followed by severe anemia requiring blood transfusion. Because of the deterioration of her renal function, she was transferred to our hospital. Examinations to determine the source of bleeding from the urinary tract, including a renal arteriogram, were negative. Tests for c-anti-neutrophil cytoplasmic antigen (ANCA) and anti-glomerular basement membrane antibody gave negative results, whereas the test for p-ANCA was positive. Renal biopsy revealed crescentic glomerulonephritis with focal necrosis. Therefore, we diagnosed rapidly progressive glomerulonephritis (RPGN) due to ANCA-associated renal disease. As a result of methypre-dnisolone pulse treatment followed by oral steroid therapy, macroscopic hematuria disappeared with marked improvement of her renal function. We considered this patient to be a rare case of RPGN with blood loss through glomerular lesions resulting in severe anemia.

Adult↗
PubMed1995

Cardiac electrophysiologic effects of parathyroid hormone in the guinea pig.

The cardiac electrophysiologic effects of parathyroid hormone (PTH) were studied in three different experimental models. Purified synthetic human parathyroid hormone (hPTH 1-84), at a dose of 30 ng/g body weight (BW), prolonged the QT interval of surface ECGs in intact guinea pigs. To further clarify the mechanisms of the QT prolongation caused by hPTH, the action potentials of guinea pig papillary muscle were recorded by conventional microelectrode techniques. hPTH (10(-7)M) prolonged the action potential duration without changing the action potential amplitude, resting potential, maximal upstroke velocity of the action potential, or maximal repolarization rate. hPTH affected only the plateau phase, in a concentration-dependent fashion. The half-maximum concentration was 6.8 x 10(-8)M for action potential duration at 30% repolarization (APD30), 3.2 x 10(-8)M for APD50, and 2.1 x 10(-8)M for APD90. In isolated single guinea pig ventricular cells, the patch clamp method was used to record the slow inward calcium current (ICa) and delayed rectifier potassium current (IK) responsible for the action potential plateau phase. hPTH increased the peak amplitude of ICa at + 10mV by an average of 42%, and increased IK at + 10mV by 85%. These results indicate that, in ventricular muscle, hPTH prolongs the action potential duration and QT interval by the balance of the prolongation effect on APD by enhancing the slow inward calcium current and the shortening effect on APD by enhancing the delayed rectifier potassium current.

Action Potentials↗
PubMed1995

Follow-up of 2,733 Japanese patients with myocardial infarction.

Two thousand, seven hundred and thirty-three patients with acute myocardial infarction (AMI) who were admitted to our 11 institutions between 1983 and 1988, examined by coronary arteriography and discharged alive, were followed for an average of 2.9 years. During the follow-up period, 212 patients (7.6%) died. The factors that governed the prognosis of myocardial infarction after discharge were advanced age, female gender, obesity, previous infarction, angina pectoris more than 1 month before the onset of AMI, post-infarction angina, multiple-vessel diseases, advanced stage by Killip's and/or Forrester's classification on admission, elevated pulmonary capillary arterial pressure, decreased cardiac index, decreased left ventricular ejection fraction, increased left ventricular end-diastolic volume and left ventricular aneurysm before hospital discharge. Patients with ventricular tachycardia or ventricular fibrillation during hospitalization showed a poor prognosis. In contrast, patients who received intracoronary thrombolysis, or emergent and/or elective percutaneous transluminal coronary angioplasty showed a favorable prognosis.

Adult↗
PubMed1995

Factors governing re-infarction in patients with myocardial infarction in Japan.

The subjects consisted of 2,733 patients with acute myocardial infarction (AMI) who were admitted to our 11 institutions between 1983 and 1988, examined by coronary arteriography, and discharged alive. The patients were followed for an average of 2.9 years after discharge. During the follow-up period, re-infarction occurred in 172 patients (6.3%). The factors associated with re-infarction were total cholesterol of more than 250 mg/dl, HDL-cholesterol of less than 35 mg/dl and diabetes mellitus. The rate of re-infarction was also high in patients who had had a previous infarction before admission, angina pectoris before or after the onset of AMI or multiple-vessel disease. In contrast, intracoronary thrombolysis reduced the rate of re-infarction.

Angina Pectoris↗
PubMed1995

Postcholecystectomy syndrome mimicking angina pectoris detected by the morphine provocation test.

A 66-year old woman had had intermittent anterior chest pain and upper abdominal pain for 15 years. Angina pectoris was diagnosed at the age of 51 years, as she had typical anginal pain that was relieved by nitroglycerine, although coronary arteriography was normal and the ergonovine provocative test was negative. She had undergone cholecystectomy at the age of 38 years. Her bile duct pressure increased markedly after morphine injection and severe pain with the aforementioned distribution was produced. Postcholecystectomy syndrome due to sphincter of Oddi spasm was diagnosed and her pain was relieved by endoscopic sphincterotomy.

Aged↗
PubMed1994

3',3",5',5"-Tetraiodophenolsulfonephthalein is a selective inhibitor of Ca(2+)-pumping ATPase in intracellular Ca2+ store.

3',3",5',5"-Tetraiodophenolsulfonephthalein (I4PSP) stimulated both Ca2+ transient levels and aggregation in response to thrombin in platelets. Ca2+ uptake into skeletal sarcoplasmic reticulum (SR) was inhibited by I4PSP (IC50, 1.8 microM) whereas that of red blood cell ghosts was not affected by it. Furthermore, I4PSP inhibited the SR Ca(2+)-ATPase activity (IC50, 1.1 microM). Kinetic analysis of the inhibitory effects of I4PSP reveals that I4PSP shows an inhibition of noncompetitive and competitive type with respect to low and high concentrations of ATP, respectively. The mode of inhibition by I4PSP is an uncompetitive type with respect to Ca2+. I4PSP decreased the decomposition rate of the phosphorylated enzyme intermediate (EP). The change in the tryptophan fluorescence of SR Ca(2+)-ATPase induced by ATP was reduced by I4PSP indicating inhibition of the EP transition from Ca2E1P to E2P. The concentration-inhibitory response curves for I4PSP in Ca(2+)-ATPase activities and fluorescence changes were closely correlated. These results suggest that I4PSP slows down the structure transition from Ca2E1P to E2P, resulting in inhibition of the Ca(2+)-ATPase activity. On the basis of these results, it is suggested that the stimulation of Ca2+ transient levels in platelets and their aggregation in response to thrombin are due to the inhibition of Ca2+ pump in intracellular Ca2+ stores by I4PSP.

Adenosine Triphosphate↗
PubMed1994

Noninvasive evaluation of the influence of aortic wave reflection on left ventricular ejection during auxotonic contraction.

To develop a noninvasive method for evaluating the influence of aortic wave reflection on left ventricular ejection, the carotid pulse wave and the pulsed Doppler wave in the left ventricular outflow tract were evaluated in 35 patients. Agreement between the pulsed Doppler waveform and the aortic flow velocity contour (obtained invasively) was verified by Fourier analysis. The carotid augmentation index was used to determine the magnitude of the aortic pressure wave reflection. A Doppler index named "DR1/3" was defined as the ratio of deceleration at the first one-third in the deceleration phase to the peak flow velocity of the pulsed Doppler. This index was validated by close correlation with the carotid augmentation index (n = 48, r = 0.70, P < 0.01). Both nitrates and nifedipine induced a significant decrease in DR1/3 (indicating an increase in left ventricular ejection flow) in relation to a reduction of the reflected pressure wave. The new noninvasive index, DR1/3, is useful in evaluating the influence of aortic wave reflection as part of the left ventricular afterload and in assessing the benefit of treatment aimed at reducing wave reflection.

Aorta↗
PubMed1994

Case report: new sonographic finding in renal infarction.

We observed a unique sonographic finding in a patient with right global renal infarction associated with an abdominal aortic dissection. Sonography in the acute phase revealed a highly echogenic and thickened perirenal fascia without demonstrable abnormality of the renal parenchyma. This finding may be helpful in the early diagnosis of renal infarction by routine sonography.

Aged↗
PubMed1994

[Relationship between insulin resistance and blood pressure].

A study designed to analyze the relationship between blood pressure and insulin resistance was conducted on 353 subjects who received medical health examinations, and who did not have obvious diabetes. Fasting plasma insulin (IRI), fasting plasma glucose (FPG), body mass index (BMI), waist hip ratio (WHR), body fat percentage, total cholesterol (TC), triglyceride, and urine sodium concentrations were measured or calculated. After analysis of the correlation's between each value, multiple regression analyses were performed. The results were as follows: 1) hypertensive subjects were significantly higher than non-hypertensives in with age, value of IRI, FPG, WHR, TC and BMI. 2) The values of IRI, WHR, and BMI were correlated each other. 3) After adjusted for age and sex by multiple regression analyses, IRI, WHR, and BMI were shown to have significant relationship to mean blood pressure. From this study, it is concluded that IRI is an indicator for insulin resistance and is related to blood pressure.

Adolescent↗
PubMed1993

A cold-inducible Bombyx gene encoding a protein similar to mammalian sorbitol dehydrogenase. Yolk nuclei-dependent gene expression in diapause eggs.

To facilitate the study of the induction of sorbitol dehydrogenase by acclimation to 5 degrees C in diapause eggs of the silkworm, Bombyx mori, two cDNA libraries from eggs and larval fat bodies were screened with anti-(sorbitol dehydrogenase) serum, and a positive cDNA was cloned from the fat-body cDNA library. 1039 nucleotides determined from the cDNA corresponded to a protein-coding region consisting of 346 amino acids. The missing regions (containing two amino acids at the 5' end and a stop codon at the 3' end) were supplemented with the genome sequence. The deduced amino-acid sequence had 45-47% identity with mammalian sorbitol dehydrogenases. The results led us to conclude that the cDNA for a Bombyx homolog of mammalian sorbitol dehydrogenase was isolated, which was designated as BmSDH. Analyses of Northern hybridization and reverse transcription/polymerase chain reaction showed that the transcript of BmSDH occurred after chilling for 40-50 days when the diapause eggs were exposed to 5 degrees C from two days after oviposition to break the diapause. The changing pattern in the amount of BmSDH transcript was well correlated with those in the activity of sorbitol dehydrogenase and the amount of the enzyme protein in diapause eggs. Further, the transcript of BmSDH was localized in yolk cells. The results indicate that the yolk nuclei-dependent gene expression of BmSDH is induced by acclimation to 5 degrees C in diapause eggs.

Amino Acid Sequence↗
PubMed1993

Free testosterone and abortion in early pregnancy.

OBJECTIVES: To investigate the relationship between percentage of free testosterone (% free T) and the abortion rate in early pregnancy. METHODS: Progesterone (P), estradiol (E2), total T, sex hormone binding globulin (SHBG), and % free T were measured in sera obtained from 60 pregnant women with normal pregnancy (n = 38) and missed abortion (n = 22) at between 4 and 12 weeks' gestation. RESULTS: P, E2, total T, and SHBG in 22 patients with missed abortion were significantly lower than those in normal group, whereas % free T was significantly higher. There was a significant negative correlation between % free T and SHBG concentration in the normal group, but not in the missed abortion group. All the subjects in whom % free T was 1.30% and higher subsequently miscarried, but no subject with % free T less than 0.70% had a miscarriage. CONCLUSIONS: The lower the % free T, the lower the rate of subsequent abortion. The value of % free T may be able to predict pregnancy outcome in early pregnancy.

Abortion, Spontaneous↗
PubMed1993

Developmental profile of the gene expression of a Bombyx homolog of mammalian sorbitol dehydrogenase during embryogenesis in non-diapause eggs.

1. By using semi-quantitative PCR analysis, changes in the amount of the transcript for a Bombyx homolog of mammalian sorbitol dehydrogenase (BmSDH) were examined during embryogenesis in non-diapause eggs. 2. Occurrence of the transcript for BmSDH correlated with the two developmental phases, the growth of embryo and the formation of larval tissues. 3. In the first phase, an increase in the amount of the transcript for BmSDH resulted from embryonic cells rather than yolk cells. 4. In the second phase, the transcript was suggested to be abundant in fat-body cells of pharate larva, because it was abundant in fat-bodies of 5th instar larvae. 5. The difference in the expression of BmSDH gene between diapause and non-diapause eggs is discussed.

Animals↗
PubMed1993

Transient rise in serum interleukin-8 concentration during acute myocardial infarction.

OBJECTIVE: To determine whether interleukin-8 (IL-8, a potent activator of neutrophils) is involved in tissue injury during ischaemia and reperfusion in patients with acute myocardial infarction. SETTING: Teaching hospital. SUBJECTS: Five consecutive patients with acute Q-wave myocardial infarction, two patients with stable angina who underwent elective percutaneous transluminal coronary angioplasty, and 10 normal controls. MAIN OUTCOME MEASURE: Serum IL-8 concentration measured by enzyme linked immunosorbent assay (ELISA) over time (every four, eight or 12 hours for 36-72 hours). RESULTS: All five patients with acute myocardial infarction had a transient but significant rise in serum IL-8 concentration (13-1100 ng/l) within 22 hours after the onset of symptoms, whereas IL-8 was not detected in any of the samples from patients with angina pectoris or normal controls. One patient who died of pump failure and two patients who had mild congestive heart failure showed the highest values (1100, 920, and 190 ng/l respectively). CONCLUSIONS: Serum IL-8 concentration showed a transient rise during the very early phase of acute myocardial infarction. In combination with several recent lines of evidence indicating the importance of injurious activities of neutrophils as a cause of tissue damage in acute myocardial infarction and the potent stimulation of neutrophils by IL-8, these results strongly suggest that IL-8 is important in the development of myocardial injury in acute myocardial infarction.

Adult↗
PubMed1993

Effect of social factors on metabolic improvement in type II diabetic patients.

Psychological and social factors can profoundly influence a patient's success in adhering to a prescribed self-care regimen. A total of 34 inpatients with type II diabetes who attended the diabetes education program at a single clinic were studied as a retrospective cohort, beginning between 6 and 12 months after discharge. At the start of the study, the patients were classified into two groups, those with good control and those with poor control of diabetes, based on the rate of change of the glycosylated hemoglobin (HbAlc) value relative to the value at admission. Data for each patient were collected retrospectively from their medical records. Patients' family function was assessed by the adaptability, partnership, growth, affection, and resolve (APGAR) scoring system. Multiple regression analysis was used to determine the effect of demographic, medical, and social factors on metabolic improvement. The family APGAR score was higher in the good control group than in the group with poor control.

Adult↗