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Biomedical subjects

H Matsuo

Publications and source records attributed to H Matsuo.

At least 127 records · Page 7Linked to original sources
PubMed2000

Sensitive detection of myocardial contraction abnormality in chronic hemodialysis patients by ultrasonic tissue characterization with integrated backscatter.

Since acoustic properties of the myocardium are sensitive to the myocardial structure and the contractile conditions of myocyte, the authors evaluated cardiac dysfunction based on the integrated ultrasonic backscatter in 18 hemodialysis (HD) patients (duration: 102 +/- 84 months, mean age: 57.6 +/- 9.7 years) and 11 age-matched normals. The cyclic variation of integrated backscatter (CV-IB) at interventricular septum (IVS) and left ventricular posterior wall (PW) was measured and compared with percent fractional shortening (%FS) and percent wall thickening (%Th). The CV-IB of HD patients was smaller than that of control subjects (IVS: 6.2 +/- 1.1 dB vs 8.2 +/- 1.1 dB, p = 0.0003 and PW: 8.4 +/- 2.2 vs 10.3 +/- 1.3, p= 0.025). No significant difference was observed in %FS and %Th between HD patients and control subjects. In HD, the ratio of velocities of early diastolic inflow (E) to late atrial inflow was decreased (0.7 +/- 0.2 vs 1.1 +/- 0.7, p = 0.049) and deceleration time of E was prolonged significantly (200 +/- 28 msec vs 159 +/- 30 msec, p = 0.0082). In the absence of overt cardiac systolic dysfunction, myocardial damage indicated as a decrease in CV-IB and diastolic dysfunction identified on transmitral velocity waveform were detected, which may reflect from the myocardial fibrosis. As a mechanism, pressure overload, hyperparathyroidism, and anemia were neglected, and the other humoral factors may contribute to the myocardial damage in chronic renal failure.

Aged↗
PubMed2000

Evaluation of effective aortic regurgitant orifice area and its effect on aortic regurgitant volume with Doppler echocardiography.

The authors measured the aortic regurgitant orifice area (ROA) using Doppler echocardiography and attempted to clarify how important the ROA is in determining the regurgitant volume (RV) in 22 patients with chronic aortic regurgitation (AR). The RV was calculated from the difference between the left ventricular ejection flow volume and transmitral inflow volume as measured by Doppler echocardiography. The ROA was obtained by two methods: RV/time velocity integral of AR jet measured by continuous wave Doppler (calculation method) and manual tracing of minimum cross-sectional area of short-axis color Doppler. The RV ranged from 10 to 90 mL/beat and the ROA by calculation method was from 0.05 to 0.35 cm2, which showed a strong correlation (r = 0.93, p < 0.001). The time velocity integral of aortic regurgitant jet showed a poor correlation with the RV (r = 0.45, p < 0.05). The values of ROA by the two methods showed a good correlation (r = 0.93, p < 0.001). Thus, the authors conclude that the ROA is a basic determinant of the RV in AR and that color Doppler can be employed to precisely assess the ROA.

Adult↗
PubMed2000

Effects of perindopril on left ventricular remodeling and aortic regurgitation in rats assessed by echocardiography.

This study investigated the effect of the angiotensin-converting enzyme (ACE) inhibitor perindopril on left ventricular (LV) remodeling and cardiac function in rats with aortic regurgitation (AR). Twenty male Sprague-Dawley rats in which AR was produced by closed-chest aortic valve puncture were divided into untreated and perindopril-treated (5 mg/kg/day) rats. Ten control rats were sham-operated. Blood pressure, body weight, and echocardiographic recordings were followed every 2 weeks for a period of 12 weeks. LV dimension (LVD) and fractional shortening (FS) were calculated. The heart was finally excised for weight, hydroxyproline measurements, and histopathology. At 12 weeks, end-diastolic LVD increased in untreated rats (10.8 +/- 0.2 mm) but did not dilate in treated rats (9.6 +/- 0.3 mm, p < 0.01 vs untreated rats). FS decreased from 6 weeks in untreated rats (27.3 +/- 0.9% at 12 weeks), but did not change in treated rats (33.8 +/- 0.5%, p < 0.001). The ratio of LV weight to body weight in untreated rats (2.62 +/- 0.11 mg/g, p < 0.05) was higher than in sham-operated rats (1.52 +/- 0.02 mg/g) and than in treated rats (1.95 +/- 0.07 mg/g). Interstitial collagen accumulation histopathologically increased in untreated rats and was inhibited in treated rats. LV collagen of untreated rats (1.46 +/- 0.08 mg/100 mg, p = 0.03) was higher than those of treated (1.08 +/- 0.09 mg/100 mg) and sham-operated rats (1.06 +/- 0.14 mg/100 mg). Perindopril inhibited LV remodeling induced by volume overload and preserved LV function in AR rats.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2000

Release of endothelins and platelet-activating factor by a rat pleural mesothelial cell line.

Thrombin is a multifunctional serine protease. It is generated in inflammatory processes and induces the proliferation and chemotaxis of a variety of cells including mesothelial cells (MTCs). MTCs are epithelial cells derived from the mesoderm, as are the vascular endothelial cells. Since thrombin acts on endothelial cells to produce platelet-activating factor (PAF) and endothelin (ET)-1, it was hypothesized that MTCs also produce PAF and ET via the action of thrombin. Rat pleural MTC (RMTC, 4/4 R.M.-4) monolayers were cultural in tissue culture dishes for various periods. The supernatants were fractionated by means of high-performance liquid chromatography to determine the ET isoforms and PAF species present. Immunoreactive ET was measured using an enzyme-linked immunosorbent assay, and PAF was measured by means of a bioassay using a platelet aggregometer. ET-1, ET-2 and ET-3 were detected in RMTC-conditioned medium, and the predominant isoforms were ET-1 and ET-2. RMTCs mainly released C16:0 PAF into the supernatant. Immunoreactive ET and PAF were released via the action of thrombin. Synthetic PAF significantly induced secretion of ET, but the PAF receptor antagonists, WEB2086 and E6123, failed to modulate thrombin-induced ET release. These results indicate that thrombin acts on pleural rat mesothelial cells to release ET and PAF, which may play a role in the development of pleurisy.

Animals↗
PubMed2000

Echocardiographic observation of acute myocarditis with systemic lupus erythematosus.

Although myocarditis from a series of autopsies of patients with systemic lupus erythematosus was frequently observed, the incidence of clinically apparent myocardial dysfunction was low. A 30-year-old woman with systemic lupus erythematosus was examined by echocardiography. An acoustic densitometry was followed at the left ventricular posterior wall throughout the clinical course. A decrease in the magnitude of cyclic variation of integrated backscatter (IB) was observed before treatment. Following the combined treatment, steroid and cyclophosphamide, a repeated ultrasonic tissue characterization showed an increase in the magnitude of cyclic variation of IB. It is thought that ultrasonic tissue characterization may be a useful method to evaluate the impairment of contraction, and to follow up the clinical course of myocardial involvement in systemic lupus erythematosus.

Adult↗
PubMed2000

Degos' disease with constrictive pericarditis: a case report.

A 47-year-old man with Degos' disease was examined by echocardiography, which showed hypokinesis of the apical left ventricular wall with pericardial effusion. To evaluate the myocardial perfusion and coronary flow reserve, 201Tl scintigraphy and intracoronary Doppler flowmetry were performed. The coronary flow reserve was not decreased nor was there angiographical coronary stenosis, although a pressure study revealed constrictive dysfunction of both ventricles. The constrictive pericarditis might have been induced by pericardial vasculitis, thereby causing the left ventricular wall motion abnormality.

Humans↗
PubMed2000

Transesophageal echocardiographic observation of multiple myeloma involving the pericardium: a case report.

This report presents a case of multiple myeloma with a mass lesion on the pericardium and pericardial effusion. The response to intrapericardial combination chemotherapy (cisplatin and betamethasone) was evaluated by repeated transesophageal echocardiograms. Following the treatment, complete resolution of the tumor and effusion were observed for 6 months after which the patient died of bacterial pneumonia. Intrapericardial combination chemotherapy can be an effective treatment for myelomatous involvement of the pericardium.

Aged↗
PubMed2000

Comparative analysis of the effects of gonadotropin-releasing hormone agonist on the proliferative activity, apoptosis, and steroidogenesis in cultured porcine granulosa cells at varying stages of follicular growth.

This study was conducted to analyze comparative effects of gonadropin-releasing hormone (GnRH) agonist on the proliferation, apoptosis, and differentiated function of cultured porcine granulosa cells from varying follicle stages. Comparative analyses of porcine granulosa cells from varying follicle stages to respond to GnRH agonist were performed in terms of proliferating cell nuclear antigen (PCNA) expression, occurrence of apoptosis, and 17beta-estradiol (E2) and progesterone (P) secretion. PCNA expression was examined by the avidin/biotin immunoperoxidase method with a monoclonal antibody to PCNA, and apoptosis was assessed by in situ DNA 3'-end labeling method and DNA fragmentation analysis. E2 and P were measured by radioimmunoassays. The PCNA positive rate of granulosa cells cultured in the presence of GnRH agonist (10(-9) M) was lower compared with that of cells cultured in the absence of GnRH agonist. However, the apoptosis positive rate was higher, and E2 and P secretion by cultured granulosa cells was lower in the presence of GnRH agonist (10(-9) M) compared with that in the absence of GnRH agonist. The inhibitory effect of GnRH agonist on PCNA positive rate of cultured cells was prominent in granulosa cells from small and medium but not from large follicles. By contrast, the inhibitory effect of GnRH agonist on E2 and P secretion by cultured cells was prominent in granulosa cells from large but not small and medium follicles. The stimulatory effect of GnRH agonist on apoptosis positive rate of cultured cells was, however, uniform regardless of the stages of follicular growth. These results demonstrate that GnRH agonist exerts diverse actions on granulosa cells over the course of follicular growth. One downregulates granulosa proliferation in immature follicles as well as steroidogenesis in mature follicles, and the other upregulates apoptosis of granulosa cells regardless of the stages of follicular growth.

Animals↗
PubMed2000

Changes in proliferative potential, apoptosis and Bcl-2 protein expression in cytotrophoblasts and syncytiotrophoblast in human placenta over the course of pregnancy.

In order to evaluate placental trophoblast proliferation and apoptosis during pregnancy, we investigated proliferating cell nuclear antigen (PCNA) expression, apoptosis and Bcl-2 protein expression in the human placenta using avidin/biotin immunoperoxidase method to examine PCNA and Bcl-2 protein expression, and TUNEL method to assess apoptosis. The appearance of apoptotic cells in very early term placental trophoblasts was also examined by transmission electron microscopy. PCNA was immunolocalized in the nuclei of cytotrophoblasts (C-cells). Determination of the mean percentage of PCNA-positive nuclei of C-cells revealed that PCNA expression in C-cells was highest in very early term (4th to 5th wk) placentas and significantly decreased with the advance of pregnancy. Bcl-2 protein was immunolocalized in the cytoplasm of syncytiotrophoblast (S-cell), being least abundant in very early term placentas, less abundant in early term and midterm placentas, and most abundant in term placentas. On the basis of TUNEL method, apoptosis was apparent in the nuclei of both C-cells and S-cell. The apoptosis positive rate of C-cell nuclei was highest in very early term 4th to 5th wk placentas, and significantly decreased in early term 7th to 9th wk and midterm placentas, but somewhat increased in term placentas compared to that in midterm placentas. On the other hand, apoptosis positive rate of S-cell nuclei was remarkably higher only in very early term 4th to 5th wk placentas compared to that in early term, midterm and term placentas. Transmission electron microscopy revealed the appearance of apoptotic nucleus in very early term placental trophoblasts. These results demonstrate for the first time that apoptosis in the human normal placenta predominates in both C-cells and S-cell in very early term 4th to 5th wk pregnancy and drastically diminished after 7th wk of pregnancy. An apparent increase in apoptosis in C-cells in term placentas compared to that in midterm placentas may reflect aging of the placenta or parturition-associated biological change. The abundant expression of Bcl-2 protein in S-cell in term placentas may be responsible for the diminished occurrence of apoptosis in S-cell in term placentas.

Abortion, Induced↗
PubMed2000

Efficient introduction of macromolecules and oligonucleotides into brain capillary endothelial cells using HVJ-liposomes.

In this study, we examined the feasibility of introducing macromolecules into cultured mouse brain capillary endothelial cells (MBEC4 cells) by utilizing the hemagglutating virus of Japan (HVJ)-liposomes with fusogenic activity. We used fluorescein isothiocyanate dextran (FITC-Dextran) and FITC-labeled oligodeoxynucleotide (FITC-ODN) as models of a macromolecule and an ODN, respectively. Intracellular fluorescence appeared rapidly after the exposure of MBEC4 cells to FITC-Dextran-containing HVJ-liposomes, and remained detectable for at least 3 days. Only a control level of intracellular fluorescence was seen after treatment with FITC-Dextran alone, FITC-Dextran with empty HVJ-liposomes or FITC-Dextran-containing liposomes without fusogenic activity. In the early phase after administration (0-30 min), the introduction of FITC-Dextran into MBEC4 cells by the HVJ-liposome method resulted in a rapid and time-dependent increase of intracellular fluorescence intensity. Moreover, FITC-ODN was also introduced into MBEC4 cells by the HVJ-liposome method, although FITC-ODN alone was not introduced. These results indicate that the HVJ-liposome method is useful for the efficient introduction of macromolecules, including ODN, into brain capillary endothelial cells.

Animals↗
PubMed2000

Cardiac sympathetic denervation from the early stage of Parkinson's disease: clinical and experimental studies with radiolabeled MIBG.

UNLABELLED: Autonomic disorder is not infrequent in patients with akinetic-rigid syndromes, including idiopathic Parkinson's disease. In the advanced stage of Parkinson's disease, abnormal blood pressure responses, such as orthostatic hypotension and abnormal circadian blood pressure rhythm, may occur. Few cases of reduced 123I-metaiodobenzylguanidine (MIBG) accumulation in the heart or limbs of Parkinson's disease patients have been reported. However, whether reduced accumulation is caused by damage to the postganglionic sympathetic nervous system or by central autonomic failure corresponding to abnormalities in blood pressure regulation is unknown. METHODS: We evaluated sympathetic denervation in 32 Parkinson's disease patients using 123I-MIBG cardiac scintigraphy and compared the findings with those for autonomic dysfunction detected by orthostatic hypotension and diurnal blood pressure variation. Cardiac 125I-MIBG accumulation was also determined in an experimental model of Parkinson's disease using mice pretreated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). RESULTS: Cardiac 123I-MIBG accumulation 15 min after injection and 4 h after injection was markedly reduced in the Parkinson's disease patients (heart-to-mediastinum ratio: 1.58 +/- 0.37 and 1.33 +/- 0.28, respectively) compared with 7 healthy volunteers (2.42 +/- 0.27 and 2.60 +/- 0.15, respectively). This reduction was observed even at the earlier stages of physical activity or disease duration and also in patients with normal blood pressure response and variation, indicating that the marked decrease in cardiac 123I-MIBG accumulation may be a special feature of Parkinson's disease. Pretreatment with a total dose of 100 mg/kg MPTP, which is the standard dose used to destroy the dopaminergic neurons in models of Parkinson's disease, significantly reduced cardiac 125I-MIBG accumulation in C57BL/6 mice. Interestingly, the reduction of 125I-MIBG accumulation was still significant when MPTP was reduced to 5 mg/kg. These findings indicated that the postganglionic sympathetic nerves may be damaged by MPTP or unknown toxic substrates in experimental or human Parkinson's disease during the early stage, because dopaminergic neurons and sympathetic nerves are substantially similar in their plasma membrane transporters. CONCLUSION: Cardiac scintigraphy with 123I-MIBG may be used as a new imaging approach in the diagnosis and characterization of akinetic-rigid syndromes, especially Parkinson's disease.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2000

Quantitative prediction of metabolic inhibition of midazolam by erythromycin, diltiazem, and verapamil in rats: implication of concentrative uptake of inhibitors into liver.

To evaluate the degree of drug-drug interaction concerning metabolic inhibition in the liver quantitatively, we tried to predict the plasma concentration increasing ratio (R) of midazolam (MDZ) by erythromycin (EM), diltiazem (DLZ), or verapamil (VER) in rats. MDZ was administered through the portal vein at the steady state of plasma concentration of these inhibitors. The R values in the area under the plasma concentration curve of MDZ in the presence of EM, DLZ, and VER were 2.02, 1.64, and 1.30, respectively. The liver to plasma unbound concentration ratios of EM, DLZ, and VER at the steady state after infusion were 20.8, 1.02, and 3.01, respectively, suggesting concentrative uptake of EM and VER into the liver. The predicted R value in the presence of EM calculated by use of plasma unbound concentration was 1.03, whereas the value calculated with liver unbound concentration was 1.61, which was very close to the observed value. These findings indicated the need to consider the concentrative uptake of inhibitors into the liver for the quantitative prediction of metabolic inhibition. However, the predicted values in the presence of DLZ or VER calculated by use of liver unbound concentration were still underestimated. This result may be due to the metabolic inhibition by the metabolites of both inhibitors. Therefore, when predicting the degree of metabolic inhibition quantitatively, the inhibitory effect by coadministered drugs and the disposition of these metabolites in the liver must also be considered.

Animals↗
PubMed2000

Polymethoxylated flavones in orange juice are inhibitors of P-glycoprotein but not cytochrome P450 3A4.

The presence in orange juice of compounds that specifically inhibit the P-glycoprotein (P-gp) drug efflux transporter, but not the cytochrome P450 (CYP) isozyme CYP3A4, was investigated. The uptake of [(3)H]vinblastine, a substrate of P-gp, by Caco-2 cells was measured. An ethyl acetate extract of orange juice did not affect the initial uptake rate of [(3)H]vinblastine but significantly increased the steady-state uptake, as did cyclosporin A (20 microM), an inhibitor of P-gp. No significant effect on the uptake of 3-O-[(3)H]methylglucose or [(14)C]phenylalanine by Caco-2 cells was found, compared with the control. When the extract was separated on a Cosmosil column, the eluate with 70% methanol showed the most potent ability to increase [(3)H]vinblastine uptake. Additional separation of the 70% methanol eluate on a silica gel column with hexane-acetone (3:1) gave 3,3',4',5,6,7,8-heptamethoxyflavone (HMF) and 4',5,6,7,8-pentamethoxyflavone (tangeretin). HMF, tangeretin, and 3',4',5,6,7,8-hexamethoxyflavone (nobiletin), another methoxyflavone contained in orange juice, all increased the steady-state uptake of [(3)H]vinblastine by Caco-2 cells in a concentration-dependent manner. The order of potency of these compounds at the concentration of 50 microM was tangeretin > HMF > nobiletin. None of these methoxyflavones inhibited 6beta-hydroxylation of testosterone catalyzed by CYP3A4. The ethyl acetate extract of orange juice and these methoxyflavones also increased steady-state [(3)H]vinblastine uptake by LLC-GA5-COL300 cells (a cell line transfected with human MDR1 cDNA). We conclude that these methoxyflavones enhanced vinblastine uptake by specifically inhibiting drug efflux via P-gp. They may have potential as agents for reversing multidrug resistance or for recovering the bioavailability of certain drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Hyperbaric stress during saturation diving induces lymphocyte subset changes and heat shock protein expression.

To clarify the cellular responses and biochemical markers of hyperbaric stress, we investigated heat shock protein (hsp) expression and subset changes of human peripheral blood lymphocytes during saturation diving. Five healthy male subjects underwent a 39-day saturation dive to the maximal storage pressure of 4.1 MPa [400 meters of sea water (msw)]. During the saturation dive, lymphocyte subset changes were detected using a flow cytometer, and increased expressions of hsp 72/73 and hsp 27 were observed by Western blot analysis. Lymphocyte subset changes included a decrease in CD4:CD8 ratio and in the fraction of CD4+ T cells as well as an increase in NK cells, especially during the 400-msw bottom phase. An increased expression of hsp 27 compared to hsp 72/73 was obvious, especially during the hold period at 100 msw. These results suggest that changes in lymphocyte subsets and hsp expression are useful markers for stress responses during saturation diving. These changes may also be useful for testing the barotolerance of divers for saturation diving.

Biomarkers↗
PubMed2000

Microvascular blood is distributed more to venules than to arterioles in patients with Buerger's disease. Observation of bulbar conjunctiva by intravital microscope system.

BACKGROUND: It has been a matter of controversy whether abnormalities of organs other than extremities may be a clinical manifestation of Buerger's disease (thromboangiitis obliterans; TAO). In the present investigation, our aim was to quantitatively characterise the configuration of microvascular networks in bulbar conjunctiva, which is not affected apparently, in patients with thromboangiitis obliterans. METHODS: Nine men with thromboangiitis obliterans attended our hospital and nine male volunteers as normal controls were enrolled in this study. We observed and analysed the configuration of the network of a bulbar conjunctiva by use of intravital microscope system with computer assisted image processing functions. Microvessel density was defined as a summation of vessel length in a ROI area and tortuosity was evaluated by a ratio of vessel length to direct distance of both terminals. RESULTS: In the microcirculation of bulbar conjunctiva in thromboangiitis obliterans, arteriole diameter was significantly decreased and density of venules was significantly increased. Increased venular density was mainly explained by increased tortuosity of venules. CONCLUSIONS: Consequently, microvascular blood was distributed more to venules than to arterioles in patients with thromboangiitis obliterans. Venule/arteriole ratios of diameter, tortuosity and microvessel density may be useful parameters to characterize the configuration of microvascular networks in thromboangiitis obliterans.

Adult↗
PubMed2000

[Jichi Medical School Social Support Scale (JMS-SSS) revision and tests for validity and reliability].

OBJECTIVE: To develop a perceived social support scale for the Japanese. METHODS: Participants consisted of a total of 2,150 residents who responded to a perceived social support scale questionnaire in four communities involved in the Jichi Medical School Cohort Study at the study baseline in 1992-1994 (Analysis I) and 380 residents of Akaike town who responded to a questionnaire survey with the revised scale in 1999 (Analysis II). The first analysis was performed to confirm cross validity of the perceived social support scale measuring the availability of functional support from the spouse, family, and friends. The factor structures estimated for each district were compared with each other. The second analysis was set to revise the scale, modified in terms of a 4-point scoring format. The correlation between each item and a social desirability scale score, Cronbach alpha, and correlation coefficients between the revised scale scores and the original scale scores were calculated. RESULTS: Cross validity was confirmed based on the similarity of the factor structures of the responses obtained from the four different communities. Four selected indices supported the constancy of the factor structures across the communities. For the revised scale, two items were removed from the original scale-items measuring spousal support because of their statistically significant correlations with the social desirability scale score. The first principal component accounted for 57.0% of variance for spousal support, 68.2% for family support, and 67.0% for friends support and uni-dimensionality of the scales was confirmed. Alpha coefficients of the scales were .89, .95, and .94, respectively. Social support levels were stable over a mean period of 6.2 years. CONCLUSIONS: On an empirical basis, we have been able to develop a perceived social support scale. Homogeneous data from three different sources were obtained which were free from social desirability response bias and thus applicable for Japanese adults.

Adult↗
PubMed2000

Adrenomedullin: a new peptidergic regulator of the vascular function.

Adrenomedullin (AM) is a vasodilator peptide first identified in pheochromocytoma tissue, but endothelial cells and vascular smooth muscle cells actively secrete AM in addition to expressing AM receptors. AM dilates blood vessels through its direct action on the smooth muscle and the endothelial cell-mediated nitric oxide pathway. We have further demonstrated that AM is synthesized and secreted from macrophages, fibroblasts, cardiomyocytes and many other types of cells. AM secretion from these cells as well as the vascular wall cells are commonly stimulated with inflammatory cytokines and lipopolysaccharide. AM receptor is also widely distributed, and AM is shown to regulate production of inflammatory cytokines and cell growth. Based on these data, AM is deduced to be a multi-functional peptide participating in the regulation of vascular tone, inflammation and other physiologic events of the vasculature.

Adrenal Gland Neoplasms↗