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H Masuda

Publications and source records attributed to H Masuda.

At least 199 records · Page 11Linked to original sources
PubMed1997

Disseminated intra-abdominal cystic lymphangiomatosis with severe intestinal bleeding. A case report.

We describe cystic lymphangiomatosis with intestinal bleeding developing multiple lymphangiomas in the small intestine, mesentery, mesocolon, omentum, retroperitoneum, and spleen. Small intestinal fluorography showed multiple polypoid lesions, mainly in the jejunum. Ultrasonography, computed tomography, and magnetic resonance imaging showed diffuse cystic tumors in the mesentery and spleen. Cystic lymphangiomatosis was proved by histologic findings of the biopsied specimen at laparotomy.

Abdominal Neoplasms↗
PubMed1997

Chronic blockade of nitric oxide synthesis increases urinary endothelin-1 excretion.

OBJECTIVES: Our objective was to determine the effect of nitric oxide (NO) inhibition on renal synthesis of endothelin-1 (ET-1) in vivo. DESIGN AND METHODS: Rats were administered 500 mg/l NG-nitro-L-arginine methyl ester (L-NAME) in their drinking water or its vehicle for 2 weeks (2W-L-NAME, n = 10; 2W-CONT, n = 10) or for 6 weeks (6W-L-NAME, n = 13; 6W-CONT, n = 11). We measured the levels of albumin, NO metabolites and ET-1 both in their blood and in 24 h urine samples, and determined the expression of preproET-1 messenger RNA in the renal cortex and the inner medulla. We also examined renal histology. RESULTS: L-NAME administration for 6 weeks reduced NO metabolites both in serum (21.5 versus 3.66 nmol/ml in 6W-CONT) and in urine (5.72 versus 22.53 nmol/24 h in 6W-CONT), raised the systolic blood pressure (228 versus 162 mmHg in 6W-CONT), and the increased urinary excretion of albumin (24.29 +/- 11.66 versus 0.60 +/- 0.08 mg/day in 6W-CONT) and of ET-1 (112.0 +/- 38.3 versus 35.8 +/- 4.4 pg/day in 6W-CONT). There were no significant differences between the plasma levels of ET-1 in the control and L-NAME groups. Expression of preproET-1 messenger RNA increased in the renal cortex but not in the inner medulla in the 6W-L-NAME group. Bleeding and marked arteriolar narrowing were observed in the renal cortex of the 6W-L-NAME group. CONCLUSIONS: Prolonged inhibition of NO synthesis increases urinary excretion of ET-1 and albumin without having any effect on plasma ET-1 levels. These results do not support the hypothesis that NO plays an inhibitory role in the regulation of ET-1 in the systemic circulation, although it is possible that such a role could exist in renal tissue. However, in view of the albuminuria, a more likely explanation is that increased urinary ET-1 is secondary to L-NAME-induced renal hyperfiltration injury.

Albuminuria↗
PubMed1997

Immunogenetic study of sympathetic ophthalmia.

Sympathetic ophthalmia (SO) is very rare but it remains one of the most intractable eye diseases. In clinical manifestations and histopathologic features SO is known to resemble closely Vogt-Koyanagi-Harada's disease (VKH disease). We had reported that VKH disease was significantly associated with HLA-DRB1*04 and -DQB1*04 in Japanese patients. In this study, to investigate an HLA association with SO we performed HLA serological and PCR-based DNA typing in 16 patients and 50 healthy controls. Our study revealed that HLA-DRB1*04 (0405; Pc < 5 x 10(-4)), DQA1*03 (Pc < 5 x 10(-3)), and DQB1*04 (0401; Pc < 5 x 10(-4)) were significantly associated with SO as compared to the healthy controls but there was no significant difference in the frequencies of any DPB1 alleles between the patients and healthy controls. It can be postulated that not only the clinical manifestations but also the genetic predisposition of SO are very similar to those of VKH disease.

Female↗
PubMed1997

Autoregulation of portal circulation: a correlative study of circulation and vascular morphology.

To investigate the mechanism of portal circulation and the genesis of portal hypertension, an in vivo model was made to increase portal venous flow (PVF) by forming a bypass shunt between the femoral artery to the splenic venous branch in pigs and dogs via a regulatable pump. Using this model, an autoregulatory hemodynamics of the portal circulation and corresponding morphological changes of the intrahepatic vascular system were determined. Immediately after blood flow increase (100 mL/min) to the portal vein, PVF increased to the baseline level plus bypass shunt flow. But, PVF returned to the baseline level within 1 h for both animals. Portal venous resistance (PVR) at 1 h was significantly higher than the baseline level (P < 0.05). By histometric analysis of the cross-sectional area of the portal and hepatic venous branches (CSA-PV, CSA-HV) using the biopsized liver, CSA-HV at 1 h was 27.6% of the CSA-HV of the baseline level in dog, which showed narrowing and contractive changes of the hepatic venous branches, and CSA-PV at 1 h was 36.4% of the CSA-PV of the baseline level in pig, which showed narrowing and contractive changes of the portal venous branches. It is suggested that a tone of the intrahepatic vascular system has an important role in the portal autoregulatory hemodynamics.

Animals↗
PubMed1997

Prognostic factors for renal cell carcinoma: a multivariate analysis of 320 cases.

BACKGROUND: We performed a multivariate analysis of clinical variables in 320 patients with renal cell carcinoma to identify important prognostic factors for long-term survival. METHODS: We retrospectively reviewed the medical records of 320 patients who presented with renal cell carcinoma. Survival curves were calculated by the Kaplan-Meier method and statistical differences were determined by the log-rank test. Significant prognostic factors were evaluated by Cox's multivariate proportional hazard model. RESULTS: The median follow-up period was 29 months. The overall survival rates at 1, 5, and 10 years were 90.0%, 77.6%, and 69.9%, respectively. Seventeen of the 19 prognostic factors evaluated were shown to be significant by the log-rank test: patient age, sex, performance status, body temperature, erythrocyte sedimentation rate (ESR), levels of hemoglobin, alpha 2-globulin, C-reactive protein, fibrinogen, immunosuppressive acidic protein (IAP), size or involvement of tumor (T classification), regional lymph node involvement (N classification), extent of metastasis (M classification), pathologic grade, tumor cell type, mode of tumor infiltration, and the modality of treatment (curative surgery). Among them, the body temperature, ESR, alpha 2-globulin, fibrinogen, IAP, and mode of tumor infiltration were excluded from multivariate analysis because of missing data. Curative surgery was also excluded because it is a treatment modality and different from the other variables which are clinical or pathologic characteristics. From the remaining 10 variables, multivariate analysis showed that age (P = 0.0389), N classification (P = 0.0289), and M classification (P < 0.0001) were important and independent prognostic factors for long survival. CONCLUSION: This analysis showed that age, N classification, and M classification were the most important factors predicting long-term survival of patients with renal cell carcinoma.

Adult↗
PubMed1997

Differences in sialic acid-galactose linkages in the chicken egg amnion and allantois influence human influenza virus receptor specificity and variant selection.

Human influenza viruses are more efficiently isolated by inoculating patient samples into the amniotic rather than the allantoic cavity of embryonated chicken eggs. This type of cultivation selects virus variants with mutations around the hemagglutinin (HA) receptor binding site. To understand the molecular basis of these phenomena, we investigated the abundances of sialic acid (SA) linked to galactose (Gal) by the alpha-2,3 linkage (SA alpha2,3Gal) and SA alpha2,6Gal in egg amniotic and allantoic cells and in Madin-Darby canine kidney (MDCK) cells. Using SA-Gal linkage-specific lectins (Maackia amurensis agglutinin specific for SA alpha2,6Gal and Sambucus nigra agglutinin specific for SA alpha2,3Gal), we found SA alpha2,3Gal in both allantoic and amniotic cells and SA alpha2,6Gal in only the amniotic cells. MDCK cells contained both linkages. To investigate how this difference in abundances of SA alpha2,3Gal and SA alpha2,6Gal in allantoic and amniotic cells affects the appearance of host cell variants in eggs, we determined the receptor specificities and HA amino acid sequences of two different patient viruses which were isolated and passaged in the amnion or in the allantois and which were compared with MDCK cell-grown viruses. We found that the viruses maintained high SA alpha2,6Gal specificities when grown in MDCK cells or following up to two amniotic passages; however, further passages in either the amnion or allantois resulted in the acquisition of, or a complete shift to, SA alpha2,3Gal specificity, depending on the virus strain. This change in receptor specificity was accompanied by the appearance of variants in the population with Leu-to-Gln mutations at position 226 in their HA. These findings suggest that lack of SA alpha2,6Gal linkages in the allantois of chicken eggs is a selective pressure for the appearance of host cell variants with altered receptor specificities and amino acid changes at position 226.

Allantois↗
PubMed1997

Loss of arterial dilation in the reendothelialized area of the flow-loaded rat common carotid artery.

We have investigated regenerated endothelial cells and their possible contribution to arterial dilation in response to increased blood flow in rat common carotid artery (CCA). After endothelial denudation using a balloon catheter in the left CCA, an arteriovenous shunt was constructed between the left CCA and the left external jugular vein at 20 mm distal from the orifice in the denuded group. Animals that were given the arteriovenous shunt without denudation were used to form the nondenuded group. The blood flow rate in the left CCA was increased by sixfold after operation in the denuded group. We observed that endothelial cells were gradually regenerated from the orifice to the distal area and that the reendothelialized area after 4 to 8 weeks was approximately one third of the left CCA (5.31 +/- 1.49 mm at 4 weeks, 5.47 +/- 1.56 mm at 8 weeks). In the reendothelialized area of the left CCA after 4 to 8 weeks, the lumen diameter was significantly smaller than that of the nondenuded group and showed no significant difference from age-matched nonsurgical animals. The intimal and medial thickening, which would result in arterial stenosis in the reendothelialized area, was not observed in the denuded group, although the denuded control showed significant intimal thickening. From these results, we conclude that regenerated endothelial cells reduce intimal thickening but do not respond to increased blood flow to dilate the artery.

Angioplasty, Balloon↗
PubMed1997

Effects of growth hormone-releasing hormone (GRF) analogs, bovine and rat GRF on growth hormone secretion in cattle in vivo.

Effects of bovine and human growth hormone-releasing hormone (GRF) analogs (bGRF(1-29)-NH2: bGRF-29, [D-Ala2, Ala15]-bGRF-29, [D-Ala2]-hGRF(1-29)-NH2: [D-Ala2]-hGRF-29), bovine GRF (bGRF(1-44)-NH2: bGRF-44), as well as rat GRF (rGRF) on GH release were studied in female calves. Intravenous (i.v.) bolus injections of 0.25 microg/kg BW of bGRF-29, [D-Ala2, Ala15]-bGRF-29, and [D-Ala2]-hGRF-29 stimulated GH release. Plasma GH levels began to rise 10 min after the injection of each peptide, and significant increases in GH concentrations were obtained at 60, 180 and 150 min after the injection of bGRF-29, [D-Ala2, Ala15]-bGRF-29 and [D-Ala2]-hGRF-29, respectively. The concentrations of GH 80 min after the injection of [D-Ala2, Ala15]-bGRF-29 were significantly higher than those after the injection of [D-Ala2]-hGRF-29 (except at 80 and 90 min) or bGRF-29. The i.v. bolus injections of 0.25 microg/kg BW of bGRF-44 and rGRF stimulated GH release, and the GH-releasing potency of rGRF was approximately equal to that of bGRF-44. The plasma GH responses to the repeated i.v. injection of bGRF-29 or [D-Ala2, Ala15]-bGRF-29 at 2-h intervals were examined. bGRF-29 acutely increased plasma GH levels after each injection, and the high GH levels decreased to the basal values within 2 h. In contrast, high GH levels induced by [D-Ala2, Ala15]-bGRF-29 were gradually decreased but not lowered to basal values throughout the experiment. These results show that [D-Ala2, Ala15]-bGRF-29 has longer-lasting and greater GH-releasing activity than the other GRF analogs in female calves, and the GH-releasing potency of rat GRF is approximately equal to that of bovine GRF in cattle in vivo.

Animals↗
PubMed1997

[Study of directional differences on static and stress urethral pressure profiles of female urethra].

PURPOSE: We investigated the female continence mechanisms by comparing directional differences of static and stress urethral pressure profiles (UPP) in urinary continent females with those in stress incontinent females. Also, the mechanisms of bladder neck suspension were investigated by comparing directional differences of UPP pre- and post-operatively. METHODS: UPP at rest and under stress were recorded by means of double lumens microtip transducer catheter in 21 females without urinary incontinence (normal group) and 38 females with stress urinary incontinence (SUI group). And UPP were recorded pre- and postoperatively in 19-females of SUI group who had surgical cure of SUI (ope group). These measurements were performed on the urethral directions (anterior-direction of symphysis pubis, lateral and posterior) to which the pressure sensor in the catheter were pointed. Pressure transmission ratios (PTR) were calculated in each quartile dividing functional urethral length (FUL) into four equal lengths. We compared the parameters (the maximum urethral closure pressure = MUCP, FUL and PTR) when the sensor lies at the anterior, lateral and posterior direction in each group. The parameters in normal group were compared with those in SUI group in each direction and those in ope group were, compared pre- and postoperatively. RESULTS: In all groups, MUCP is always highest in the anterior direction but FUL shows no differences in the three directions. In all directions, MUCP and FUI are higher in the normal group than in the SUI group and there is no significant change in MUCP and FUL following successful bladder neck suspension. In the normal group, PTR of anterior, lateral and posterior urethra were approximately equal, but SUI group patients demonstrated significantly decreased PTR in the lateral and posterior urethra in comparison with PTR observed in the anterior urethra. Also, PTR of the anterior urethra in the SUI group approximates that in the normal group but PTR of the lateral and posterior urethra are lower in the SUI group than in the normal group. In the ope group, in the proximal three-quarters of the FUL, PTR in the lateral and posterior urethra approximated to those in the anterior urethra postoperatively. CONCLUSION: These findings suggest that urethral support is destructed in the SUI group as mentioned in DeLancey's hammock hypothesis and lateral and posterior weakness were corrected by bladder neck suspension. Bladder neck suspension restored the continence by constructing posterior support of urethra as the substitution for destructed urethral support.

Aged↗
PubMed1997

Genetic analysis in Japanese kindreds of congenital type I antithrombin deficiency causing thrombosis.

We have identified two novel minor deletions (case 1; -TA or -AT at nucleotide 9831-3 in exon 5 and case 2; -A at nucleotide 7640-1 in exon 4), one novel nonsense mutation (case 3; TAT to TAA at nucleotide 7491 in exon 4), and one recurrent nonsense mutation (case 4; CGA to TGA at nucleotide 5381 in exon 3A) in Japanese kindreds with congenital type I antithrombin deficiency. The deletion detected in case 1 represented a symmetric element (CTCTGTCTC) and possessed a direct repeat (CTCTATGTCTC). The deletion in case 2 was recognized in a consensus sequence (TGAAT) and possessed a direct repeat (GATGAA). The nonsense mutation in case 3 formed a palindrome (CCGTTAACGG) and that in case 4 was caused by a CpG dinucleotide mutation. These results confirm that the mutations of congenital type I antithrombin deficiency are not random events but are influenced strongly by DNA sequences.

Adult↗
PubMed1997

Angiotensin II increases plasminogen activator inhibitor-1 and tissue factor mRNA expression without changing that of tissue type plasminogen activator or tissue factor pathway inhibitor in cultured rat aortic endothelial cells.

Angiotensin converting enzyme inhibitors (ACE-I) have been reported to prevent the recurrence of cardiovascular events. The mechanism of this decrease, however, can not be completely explained by anti-hypertensive and anti-hypertrophic effects of ACE-I. To investigate the mechanism of this decrease, we studied the regulation of plasminogen activator inhibitor-1 (PAI-1), tissue type plasminogen activator (TPA), tissue factor (TF), and tissue factor pathway inhibitor (TFPI) by angiotensin II (Ang II) in cultured rat aortic endothelial cells. Ang II increased PAI-1 and TF mRNA expression without affecting that of TPA or TFPI. These inductions were accompanied by increases in PAI-1 and TF activities and were inhibited by a type I Ang II receptor antagonist. The results suggest that Ang II decreases the antithrombotic properties of endothelial cells which increases the chance of thrombosis. Thus, inhibition of the renin-angiotensin system may be beneficial to prevent thrombus formation in treatment of ischemic heart disease.

Angiotensin II↗
PubMed1997

[Cerebral cytochrome oxidase monitoring by near infrared spectroscopy during selective cerebral perfusion].

To evaluate selective cerebral perfusion (SCP) for brain protection, the redox state of cytochrome oxidase (Cyt. aa3) in brain tissue were studied in 27 patients with thoracic aortic repair. The redox state of Cyt. aa3 was monitored by near infrared spectroscopy (NIRS) (OM-110, Shimazu). There were no significant changes in the Cyt. aa3 redox state in 13 (Group I), the oxidation state of Cyt. aa3 decreased then recovered to control levels in 12 (Group II), and the oxidation state decreased but did not recover in 2 patients (Group III). Postoperative cerebral damage was observed in 5 patients; blindness occurred in one patient in Group I (8.3%), 2 patients developed hemiplegia in Group II (15.4%), and the 2 patients in Group III failed to reawaken (100%). The incidence of cerebral damage was significantly higher in Group III than in Groups I and II (p < 0.05). We conclude that monitoring the redox state of Cyt. aa3 using NIRS is useful in predicting postoperative cerebral damage. However, it is necessary to increase the number of measurement sites since NIRS can reflect the state in only a small area of the brain.

Aged↗
PubMed1997

[Advances in clinical laboratory tests for diabetes mellitus].

Advances in clinical laboratory tests for diabetes mellitus have been reported. 1) Examinations for diagnosis of diabetes mellitus: Assay of autoantibody to glutamic acid decarboxylase was commercially developed recently. This is useful for distinguishing insulin-dependent diabetes mellitus (IDDM) from non-autoimmune diabetes and for predicting the prognosis in IDDM. 2) Examinations for assessment of glycemic control: New methods of assessing glycemic control in patients with diabetes mellitus (glycated albumin, 1,5-anhydroglucitol) have been developed. It is important to be familiar with the characteristics of each test and to use each one properly. Because of the large interlaboratory difference in glycohemoglobin (GHb) measurement has been an issue of greatest importance, standardization of GHb measurement was required. To reduce this difference, it is recommended to remove unstable GHb and to correct the value using the JDS GHb standard. Currently, the difference has been reduced to a clinically permissible level (the fourth report of the GHb standardization committee). 3) Examinations for chronic complications in diabetes: Disturbances of the central nervous system may occur as diabetic neuropathy in patients with diabetes mellitus. Progress in thermology has revealed latent aortic occlusive disease in the legs and autonomic disturbance that lead to abnormal vascular responses. 4) Examinations for self-monitoring of blood glucose: The technology used for noninvasive blood glucose monitoring involves either radiation or fluid extraction. Each method has features predicting commercial viability.

Autoantibodies↗
PubMed1997

Non-lethal junctional epidermolysis bullosa in a dog.

We report a 4-year-old female mongrel dog with a history since birth of erosions and atrophic skin, with pigmentation and alopecia on the face, trunk and extremities, together with dystrophic nails. Light microscopy revealed subepidermal blisters with minimal inflammation and electron microscopy confirmed that the ultrastructural site of separation site was at the lamina lucida. Indirect immunofluorescence of the dog's skin detected the positive expression of laminin 5, BPAG2, integrin-alpha 6 and type VII collagen. These clinical, ultrastructural and immunohistochemical features suggested that the dog had a non-lethal subtype of junctional epidermolysis bullosa (JEB). This is the first confirmed case of non-lethal JEB in a dog and presents a possible candidate for an animal model of gene therapy. Further study should provide important information of the phenotype, pathophysiology and prognosis of non-lethal JEB in humans.

Animals↗
PubMed1997

[Composite valve graft replacement in patients with type A aortic dissection--a modified cabrol procedure].

Composite valve graft replacement of the ascending aorta and aortic valve is indicated for a variety of conditions affecting the aortic root. However, a major drawback in this operation is bleeding from the proximal suture line and coronary anastomosis especially in patient with friable root tissue involved by aortic dissection. We describe here a modified technique to take advantage of the aortic button and cabrol techniques to reattach the coronary artery ostia. We have experienced seven patients with the aortic root replacements for type A dissection using the described technique over the past two years. In view of our favorable experience, we recommend this technique especially for patient with acute dissection involving nondilated aortic annulus, in addition to the patients with Marfan syndrome or annulo-aortic ectasia.

Aged↗