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Biomedical subjects

H Yoshida

Publications and source records attributed to H Yoshida.

At least 1,027 records · Page 57Linked to original sources
PubMed1996

Characteristics of vasospastic angina with exercised-induced ischemia--analysis of parameters of hemostasis and fibrinolysis.

To characterize the vasospastic angina patients with exercise-induced ischemia, we measured hemostasis (platelet factor 4; PF4, fibrinopeptide A; FPA) and fibrinolytic parameters (tissue plasminogen activator antigen; t-PA, free plasminogen activator inhibitor-1 antigen; free PAI-1) in 15 normal subjects and 33 vasospastic angina patients without significant coronary artery stenosis (less than 50% stenosis). All of the vasospastic angina patients began to feel chest pain within 3 months before diagnostic coronary angiography. Blood samples were obtained from all of the study patients at 8:30-9:30 am before exercise 201Tl emission computed tomography. Vasospastic angina patients were divided into 2 groups; 15 patients with exercise-induced ischemia (group 1) and 18 patients without exercise-induced ischemia (group 2). On coronary angiography, the severity of coronary artery stenosis at the site of spasm in group 1 (34 +/- 5%) was greater than that in group 2 (18 +/- 3%). Plasma FPA and PF 4 levels in group 1 were also significantly higher than those in normal subjects and group 2. Plasma t-PA and free PAI-1 levels in group 1 were significantly higher than those in normal subjects and group 2. Plasma levels of free PAI-1 group 2 were also significantly higher than those in normal subjects. The present study demonstrated that all of the patients with vasospastic angina had impaired fibrinolysis, and these patients with exercise-induced ischemia showed enhanced platelet activation, an enhanced coagulation system, and advanced atherosclerotic lesions. These results suggest that vasospastic angina with exercise-induced ischemia puts patients at increased risk for thrombus formation.

Adult↗
PubMed1996

Lymphatic absorption of seal and fish oils and their effect on lipid metabolism and eicosanoid production in rats.

Eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) were distributed mainly in the sn-1 and 3 positions of seal oil triglyceride and in the sn-2 position of fish oil triglyceride. In Expt. 1, the structural distribution of EPA and DHA in lymph triglyceride of rats given seal or fish oils was similar to the distribution in the administered oils. In Expt. 2, seal oil-rich or fish oil-rich fats having constant polyunsaturated/monounsaturated/saturated fatty acids and n-6/n-3 polyunsaturated fatty acids ratios were fed to rats for 3 weeks. Seal oil more effectively reduced plasma and liver triglyceride than fish oil. Ratio of the productions of aortic prostacyclin and platelet thromboxane A2 stimulated by thrombin was significantly higher in rats fed seal oil than in those fed fish oil. The results suggested that the different intramolecular distribution of EPA and DHA in dietary fat affected lipid metabolism differently in rats.

Absorption↗
PubMed1996

Antimutagenic effects of ajoene, an organosulfur compound derived from garlic.

The antimutagenic effects of ajoene, which is an organosulfur compound derived from garlic, were investigated by the Ames test. Ajoene inhibited mutagenesis induced by both benzo[a]pyrene (B[a]P) and 4-nitro-1,2-phenylenediamine (NPD) in a dose-dependent manner. In particular, NPD-induced mutagenesis was more effectively suppressed by ajoene than the B[a]P-induced type. Furthermore, the inhibition of mutagenesis by ajoene was more effective for transition-type mutations than for the frame shift type. HPLC analysis of B[a]P metabolism in the presence of the rat liver microsomal fraction (S-9) showed that ajoene dose-dependently inhibited the metabolic activation of B[a]P. This suggests that ajoene affected the metabolic enzymes in the S-9 fraction.

Animals↗
PubMed1996

Electrophoretic study of lactate dehydrogenase and alkaline phosphatase isoenzymes of the Mongolian gerbil (Meriones unguiculatus).

Lactate dehydrogenase and alkaline phosphatase isoenzymes of the Mongolian gerbil were examined using electrophoretic techniques and were compared with those of the mouse, rat, and guinea pig. Five isoenzymes of lactate dehydrogenase (LDH) were detected in the gerbil with LDH2 and LDH5 being equally dominant. Two bands of alkaline phosphatase (ALP) were distinguished in sera treated with neuraminidase in the gerbil and the relative activity of the cathodic fraction was greater than those of the mouse and rat. Genetic polymorphism was not found among the coat color variants of the Mongolian gerbil. A comparative study on LDH and ALP revealed distinct interspecific differences in the rate of the electrophoretic migration of the respective isoenzymes among the mouse, rat, guinea pig, and the Mongolian gerbil.

Alkaline Phosphatase↗
PubMed1996

Left ventricular hypertrophy in mild essential hypertension. Its progression, prediction and treatment strategy.

Since the pathogenesis of left ventricular hypertrophy (LVH) in hypertension is thought to be multifactorial, the antihypertensive strategy also has to be multifaceted. Diagnosis of LVH is more reliable than ever with echocardiography either of the M-mode or 2D method. Diagnostic criteria have already been proposed by Ganau et al who classified LV morphology into 4 different sectors based on the standard values of left ventricular mass index (LVMI) and relative wall thickness in diastole (RWTd); normal, concentric remodeling, concentric hypertrophy and eccentric hypertrophy. The concentric hypertrophy pattern is the most risky with regard to prognosis. Therefore, its detection and prediction for further progression have to be conducted with relatively easy routine work-up procedures such as echocardiography and maximal exercise testing. The prediction of LVH progression has already been proposed based on several studies conducted in patients with borderline or mild hypertension. The following two predictors were defined as LVMI > 124 g/m2 and peak Ps at maximal exercise testing > 200 mmHg. Therefore, the patient who meets these criteria has to be treated with medications that are appropriately selected on an individualized basis. Both hyperinsulinemia and insulin resistance are thought to be involved in the initiation, promotion and potentiation of remodeling of the LV in hypertension. Physical fitness also seems to be decreased in a parallel manner. Selection of the most appropriate drug for a given patient has to be individually determined based on the risks that have to be corrected. Finally, arteriosclerosis, which is almost always initiated and progresses in concert with hypertension, must also be targeted with regard to such prognostic aspects as cardiovascular morbidity and mortality. Arteriosclerosis is pathogenetically independent from hypertension, but usually behaves in concert with it. Selection of medication must be focussed on an individualized basis not only for LVH, but also for improvement in arterial elasticity. Further clinical research is still needed to provide more reasonable approaches to patients with hypertension.

Angiotensin II↗
PubMed1996

Spectral properties and quantitative evaluation of hypernasality in vowels.

A new technique for evaluating hypernasality using an acoustic approach is presented. In a preliminary study using this technique, nasal resonance was assessed in 17 normal subjects and 16 subjects judged to be hypernasal. Analyses of the one-third-octave power spectra revealed an increase in power level between the first and second formant, and a reduction in the power level in second and third formant regions among utterances judged to be hypernasal. Factor analysis of the perceptual ratings revealed that the consensus perception of hypernasality accounted for 71% of the total variance. An additional 8% was accounted for by individual differences. Multiple regression analysis revealed a high correlation between the consensus perception of hypernasality and the variance in two acoustic-power levels, these being the power level between the first and second formant and the power level of the second and third formant regions.

Adolescent↗
PubMed1996

Circulation of type 1 wild poliovirus in northern Vietnam during 1991-1994.

From 1991 to 1994, 143 polioviruses were isolated from patients with acute flaccid paralysis in northern Vietnam. Of these 143 isolates, 133 were type 1 and five of each were type 2 and type 3. These isolates were intratypically differentiated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Of the 133 type 1 isolates, 113 were wild strains and only 20 isolates were of Sabin vaccine-like strains. These 113 isolates were divided into seven groups by PCR-RFLP patterns and were also classified into three genomic groups by nucleotide sequencing and phylogenetic analysis. One of the three genomic groups accounted for the majority (75) of these isolates. The isolates belonging to the predominant group were found during 1991-1993. The second group, which included 17 isolates, were detected only in 1993. These isolates had genome sequence similar to isolates in southern Vietnam in the same year. The third group of isolates were detected only in 1991 and were considered to be Mahoney-like wild strains. All isolates examined were different from those obtained in other countries. In 1994, however, no wild-type polioviruses were isolated in our study. These results reveal that three unique strains were circulating in northern Vietnam in recent years, and indicate that the incidence of poliomyelitis due to wild poliovirus is decreasing.

DNA, Viral↗
PubMed1996

Coexpression of thrombopoietin and c-mpl genes in human acute myeloblastic leukemia cells.

Thrombopoietin (TPO) is a recently identified hematopoietic growth factor that is essential for the growth and development of megakaryocytes. We have previously shown that TPO induces proliferation of acute myeloblastic leukemia (AML) cells in vitro. In this study, we have examined the expression of TPO and its receptor c-mpl in a series of AML cases and human leukemia cell lines. The mRNA transcripts of TPO were detectable in 18 of 50 AML cases and in some myeloid leukemia cell lines (HEL, M07E and CMK) by means of reverse transcriptase polymerase chain reaction (RT-PCR). In addition, TPO transcripts were coexpressed with c-mpl transcripts in 10 of 50 AML cases and in HEL, M07E and CMK cells. With regard to the French-American-British (FAB) classification, coexpression OF TPO and c-mpl was observed with high frequency in AML cases of M7-type. Despite the TPO expression in a substantial fraction of leukemia cells, biological activity of TPO was not found in the conditioned medium that was obtained from cultivation of TPO mRNA-positive leukemia cells. These results suggest that TPO may not commonly participate in the abnormal growth of AML cells as an extracellular autocrine growth factor.

Base Sequence↗
PubMed1996

Chromosomal translocation t(X;18) in human synovial sarcomas analyzed by fluorescence in situ hybridization using paraffin-embedded tissue.

Synovial sarcoma is characterized cytogenetically by translocation t(X;18)(p11.2;q11.2). In this study, 28 cases that had been diagnosed initially as synovial sarcoma, including 2 fibrosarcomas, and 1 leiomyosarcoma were collected and examined for translocation t(X;18) on paraffin-embedded tissues by fluorescence in situ hybridization (FISH). Of the synovial sarcomas, 25 showed findings consistent with translocation t(X;18) with an additional copy signal for the total probe of X and 18 chromosomes. The other three cases, as well as the two fibrosarcomas and the leiomyosarcoma, did not show this translocation. One (case 26) of three negative cases was diagnosed finally as leiomyosarcoma and another (case 27) as malignant peripheral nerve sheath tumor from histological and immunohistochemical analysis. Thus, in all, 25 (96%) of 26 synovial sarcomas showed findings consistent with translocation t(X;18). In summary, translocation t(X;18) is a chromosomal aberration specific for synovial sarcoma. The fluorescence in situ hybridization technique can be used even on cells from paraffin-embedded tissues, and is a useful diagnostic aid for synovial sarcoma.

Adolescent↗
PubMed1996

[Alzheimer's disease and trace elements].

The etiology of Alzheimer's disease (AD) still remains unknown in spite of intensive research efforts. Recent genetic linkage studies have been reported regarding some candidate genes for familial Alzheimer's disease, such as amyloid precursor protein (APP) gene and apolipoprotein E gene. On the other hand, several risk factors of AD have been revealed by epidemiological studies, including age, family history, head trauma, thyroid dysfunctions and aluminum (Al). Our study of bulk sample analysis in AD brain using neutron activation analysis showed a significant increase of Al and iron (Fe) concentrations, especially in the cerebral cortices compared with age-matched controls. Based on these results, the possible role of trace elements on the etiopathogenesis of AD is discussed.

Alzheimer Disease↗
PubMed1996

Transient suppression of pancreatic endocrine function in patients following brain death.

To investigate pancreatic endocrine function in brain-dead patients, an intravenous glucose tolerance test (i.v. GTT) was performed in 8 brain-dead subjects maintained using the combined administration of vasopressin (ADH) and catecholamines during the first 3 days following the onset of brain death. Ten healthy adults served as control subjects. Although plasma glucose concentrations markedly increased and exceeded 300 mg/dl in most subjects just after the onset of brain death, they decreased to less than 200 mg/dl in most subjects after 24 h. The early insulin release also was significantly lower in brain dead subjects compared to controls (p < 0.01). The late insulin release was not decreased compared to controls but rather increased, which was accompanied by decreased glucose disappearance rate. The early insulin release recovered rapidly during the first 3 days following brain death without significant changes in the plasma hormone concentrations such as epinephrine, human growth hormone, thyroid-stimulating hormone, triiodothyronine, thyroxine, cortisol, and glucagon. The early insulin release and the plasma glucose concentration just before i.v. GTT was negatively correlated (R = -0.55, p < 0.05). We suggest awaiting recovery from hyperglycemia and early insulin release provides a reasonable approach to transplantation of the pancreas.

Adult↗
PubMed1996

[Localized cardiac uptake defect with 123I-MIBG SPECT in a case with pure progressive autonomic failure].

A 60-year-old man with 3 years' history of autonomic nervous system disturbances such as orthostatic hypotension, anhidrosis and atonic bladder is presented. He had an episode of paroxysmal atrial fibrillation as well. He had neither extrapyramidal nor cerebellar signs, and was diagnosed as having pure progressive autonomic failure. His cardiac SPECT with 123I-MIBG showed the loss of uptake at the apex and the inferior wall and the diminished uptake at lateral walls. But 99mTc-tetrofosmin SPECT following an exercise stress showed a normal cardiac uptake. It was suggested that non-cardiac disease-associated postganglionic sympathetic fiber abnormality began from an inferior wall and would extend to a whole heart in this disease. The cardiac 123I-MIBG SPECT is thought to be useful for localizing the denervated area of cardiac sympathetic nervous system.

3-Iodobenzylguanidine↗
PubMed1996

[Surgical correction of total anomalous pulmonary venous drainage: an adult case of successful repair].

Total anomalous pulmonary venous drainage (TAPVD) is a rare congenital cardiac anomaly. It occurs in only 1.5% of children born with congenital heart defects. But, it is one of the most common lesions necessitating intracardiac operation in the neonatal period. We have experienced a 33-year-old man with supracardiac type TAPVD who was operated upon successfully. Cardiac catheterization showed 0.35 in Pp/Ps, 3.33 in Qp/Qs and 0.11 in Rp/Rs. The left to right shunt ratio was 77%, while the right to left shunt ratio was 23%. The operation was composed of anastomosis between the left atrium and the common pulmonary vein, patch closure of the atrial septal defect, ligation of the vertical vein and tricuspid annuloplasty. The posterior approach was adopted in anastomosis between the left atrium and the common pulmonary vein. The association of a normal pulmonary vascular resistance, a large interatrial communication and absence of a pulmonary venous obstruction was considered as factors of a favorable result.

Adult↗
PubMed1996

[Study on a predictive marker for evaluating the effectiveness of steroid therapy in IgA nephropathy-significance of extracapillary changes].

In order to obtain a useful index that can predict the effectiveness of steroid therapy in IgA nephropathy, we investigated the relationship between steroid therapy and extracapillary change. We analysed 51 cases consisting of a group of 24 cases in which steroid was administered (initial dose: prednisolone 20-60 mg/day orally, or pulse therapy), and a group of 27 cases in which steroid was not administered. First of all, we compared these two groups in terms of a clinical improvement rate over 3, 12 and 60-month-periods after the therapy, respectively. It was found that steroid therapy led to a higher improvement rate (p < 0.01-0.05), indicating that steroid is effective for IgA nephropathy. Among the group undergoing steroid therapy, the frequency of cellular crescents (C) was significantly higher (p < 0.05-0.01) in the cases in whom steroid was effective and that of fibrous crescents or adhesion (F) was significantly lower (p < 0.05-0.01). We then assessed C/F in each case of the steroid-administered group, and studied its relationship with the improvement rate. As a result, the improvement rate was below 50% in the group of C/F < 0.25, over 50% of the group of 0.25 < or = C/F < 0.75, and 100% of the group of 0.75 < or = C/F. Accordingly, we concluded that C/F could be used a parameter for predicting the effectiveness of steroid therapy in IgA nephropathy and for determining indications for steroid therapy.

Adolescent↗