Biomedical subjects

S Arima

Publications and source records attributed to S Arima.

At least 37 records · Page 2Linked to original sources

PubMed1999

Evaluation of malignancy and the prognosis of esophageal cancer based on an immunohistochemical study (p53, E-cadherin, epidermal growth factor receptor).

The subjects in this study consisted of 40 preoperative untreated esophageal squamous cell carcinoma patients. While p53 did not significantly correlate with the clinicopathological factors, E-cadherin significantly correlated with lymphatic invasion, vascular invasion, the depth of invasion, the degree of lymph node metastasis, the histological stage, and the number of lymph node metastases. Epidermal growth factor receptor (EGFR) significantly correlated with age, the depth of invasion, and the number of lymph node metastases. The 5-year cumulative survival rate was 45.7% in the p53-positive cases and 61.9% in the p53-negative cases, with no significant difference, and 87.8% in the E-cadherin-positive cases and 19.1% in the -negative cases, and the difference was significant. The prognosis was significantly poor in EGFR-positive subjects: the 5-year survival rate was 38.6% in EGFR-positive cases and 68% in -negative cases. The 5-year survival rate in E-cadherin-negative, EGFR-positive cases was 0%, while it was 91.7% in the reverse pattern, and this difference was significant. These findings suggest that both E-cadherin and EGFR are important prognostic factors, and a more precise prognosis can thus be obtained by combining them. Such a combined technique may be very useful as an indicator for grading the biological malignancy of esophageal cancer.

Adult↗

PubMed1999

Morphological effects on in-stent restenosis assessed by intravascular ultrasound imaging.

The purpose of this study was to evaluate the rupture and dissection of the vessel wall immediately after balloon dilatation by intravascular ultrasound (IVUS) imaging and to predict restenosis in patients who underwent subsequent coronary stent implantation. Stent implantation improves the long-term results of coronary angioplasty by reducing lesion elastic recoil and arterial remodeling. However, several studies have suggested that neointimal hyperplasia is the cause of instant restenosis. We recruited 60 patients in whom IVUS studies were performed immediately after successful balloon dilatation and just before stent implantation. We compared IVUS parameters with 6-month follow-up quantitative coronary angiography. This was performed in 51 lesions of 51 patients (85%). Qualitative analysis included assessment of plaque composition, plaque eccentricity, plaque fracture and the presence of dissection. In addition, minimal luminal diameter, percent diameter stenosis, percent area stenosis and plaque burden were quantitatively analyzed. Two morphological patterns after balloon dilatation were classified by IVUS. Type I was defined as absence or partial tear of the plaque without disclosure of the media to lumen (22 lesions). Type II was defined as a split in the plaque or dissection of the vessel wall with disclosure of the media to the lumen (29 lesions). At 6 months follow-up, angiographic restenosis occurred in 17 of the 51 lesions (33%). Restenosis was significantly (p < 0.05) more likely to occur in type II (13/29: 45% incidence) than in type I (4/22: 18% incidence). The assessment of plaque morphology immediately after balloon dilatation and before stent implantation provides important therapeutic and prognostic implications.

Aged↗

PubMed1999

[Effect of adenosine on isolated afferent arterioles].

We investigated the direct effect of adenosine on afferent arterioles (Af-Arts) and the receptor subtype that mediates the constrictor or dilator action of adenosine. Af-Arts were isolated from the superficial cortex of rabbit kidney and perfused in vitro. Adenosine added to either the lumen or bath constricted the Af-Arts in a dose-dependent manner. This constriction was blocked by the A1 receptor antagonist, 6-oxo-3-(2-phenylpyrazole(1,5-a)pyridin-3-yl)-1 (6H)-pyridazinebutyric acid (FK838) or 8-cyclopentyl-1, 3-dipropylxanthine(DPCPX). We also examined the effect of adenosine on preconstricted Af-Arts with norepinephrine. Adenosine added to either the lumen or bath further constricted the preconstricted Af-Arts. In the presence of FK838, adenosine added to either the lumen or bath dilated the preconstricted Af-Arts, but in a different dose-dependent manner. Adenosine-induced dilation was inhibited by the A2 receptor antagonist, 3, 7-dimetyl-1-propargylxanthine(DMPX). These data indicate that adenosine constricts Af-Arts via A1 receptors and that adenosine dilates preconstricted Af-Arts via A2 receptors when A1 receptors are blocked.

Adenosine↗

PubMed1998

Patients with familial hypertrophic cardiomyopathy caused by a Phe110Ile missense mutation in the cardiac troponin T gene have variable cardiac morphologies and a favorable prognosis.

BACKGROUND: Mutations that cause familial hypertrophic cardiomyopathy have been identified in several genes that encode contractile proteins. Patients with mutations in the cardiac troponin T (cTnT) gene have particularly poor prognosis but only mild hypertrophy. To date, no benign mutation in the cTnT gene has been reported. The clinical characteristics and prognosis of patients with the Phe110Ile mutation in the cTnT gene is unclear because few affected individuals have been identified. METHODS AND RESULTS: Forty-six probands with familial hypertrophic cardiomyopathy were screened for mutations in the cTnT gene. The Phe110Ile missense mutation was found in 6 probands. Individuals in the 6 families were analyzed genetically and clinically. Haplotype analysis was performed with markers encompassing the cTnT gene. Left ventricular hypertrophy was classified as type I, II, III, or IV according to the criteria of Maron et al. The Phe110Ile mutation in the cTnT gene was identified in 16 individuals. Two of the 6 families shared the same flanking haplotype, and 4 were different from each other. Affected individuals exhibited different cardiac morphologies: 4 had type II, 6 had type III, and 3 had type IV hypertrophy with apical involvement. Three individuals with the disease-causing mutation did not fulfill clinical criteria for the disease. The product-limit survival curve analysis demonstrated a favorable prognosis. CONCLUSIONS: Multiple independent mutations of residue 340 in the cTnT gene have been described, suggesting that this may be a "hot spot" for such events. The Phe110Ile substitution causes hypertrophic cardiomyopathy with variable cardiac morphologies and a favorable prognosis.

Adult↗

PubMed1998

Usefulness of adenosine triphosphate-atropine stress echocardiography for detecting coronary artery stenosis.

There have been few studies on adenosine triphosphate (AT) stress echocardiography. The AT stress test may have fewer adverse effects than the adenosine stress test. The addition of atropine to AT echocardiography may enhance the sensitivity for detection of coronary artery disease (CAD). The purpose of this study was to determine the utility of AT-atropine echocardiography for detection of CAD. The group studied consisted of 112 patients with suspected CAD. Sixty-one patients did not have a history of prior myocardial infarction (group I) and 51 patients did (group II). AT was infused intravenously at 180 microg/kg/min for 14 minutes. Atropine (0.25 mg intravenously, repeated up to maximum total dose of 1 mg) was administered starting after 8 minutes of AT infusion. Ischemic response was defined as new or worsening wall motion abnormality occurring during the infusion. The sensitivity and specificity for detection of CAD were assessed using the representative echocardiograms during single AT infusion and AT-atropine infusion. Sixty-two patients had CAD. Fifty-eight patients (52%) developed minor side effects that resolved promptly. The rate-pressure product (10(3)/mm Hg beats/min) was significantly increased at 12 minutes of infusion (12.4+/-3.2) compared with that at baseline (9.1+/-2.3) and that at 6 minutes of infusion (9.4+/-2.1). The sensitivity for detection of CAD was 45% for AT echocardiography and 74% for AT-atropine echocardiography. The specificity was 94% for AT echocardiography and 90% for AT-atropine echocardiography. The sensitivity and specificity of AT-atropine echocardiography was 78% and 93%, respectively, in group I, and 70% and 86%, respectively, in group II. In conclusion, AT-atropine stress echocardiography seems to be well tolerated, safe, and useful for detection of CAD.

Adenosine Triphosphate↗

PubMed1998

A new criterion combining ST/HR slope and deltaST/deltaHR index for detection of coronary artery disease in patients on digoxin therapy.

We evaluated the clinical value of a new index combining deltaST/delta heart rate (HR) index and ST/HR slope for diagnosing coronary artery disease (CAD) in patients on digoxin therapy. Exercise treadmill tests were performed by 72 patients on digoxin therapy. Simple HR-adjusted indexes of ST-segment depression during exercise (deltaST/deltaHR index) and the decline calculated from the final 12 data points relating ST-segment depression to HR (ST/HR slope) were determined. A new index was obtained by subtracting the deltaST/deltaHR index from the ST/HR slope. On thallium scintigraphy, 37 of the 72 patients showed reversible perfusion defects related to the diseased coronary artery. The new index derived from this ST-HR relation was 4.1 +/- 3.6 microV/beats/min in the ischemic group and 1.3 +/- 1.0 microV/beats/min in the group of patients without ischemia (p <0.0001). An ST-HR relation > or = 1.5 was found in 33 of the 37 patients in the ischemic group, and in 7 of the 35 patients without ischemia (p <0.0001). The sensitivity of this criterion for prediction of myocardial ischemia was 89%, the specificity was 80%, and the predictive accuracy was 85%. Thus, this new ST-HR index is useful for detecting CAD in patients on digoxin therapy.

Aged↗

PubMed1998

Coronary artery aneurysm repaired with saphenous vein patch plasty.

The presence of atherosclerotic coronary artery aneurysms is not always considered to be an operative indication. However, progressively expanded coronary artery aneurysms may have the potential for complications such as rupture or embolism. We present a case of successful repair of a coronary artery aneurysm located above the first septal perforator in the left anterior descending coronary artery using a saphenous vein patch and simultaneous construction of a right gastroepiploic artery graft to the occluded right coronary artery. Follow-up angiography at 6 months after operation revealed complete disappearance of the aneurysm with no luminal stenosis and a preserved large septal branch. The right gastroepiploic artery graft was also found to be widely patent.

Coronary Aneurysm↗

PubMed1997

Mechanisms of limited maximum coronary flow in severe single-vessel coronary artery disease in humans due to vertical steal.

We evaluated the usefulness of a decrease in the average peak velocity from 4 to 10 minutes after infusion of dipyridamole for detecting myocardial ischemia in 50 patients, including patients with a prior myocardial infarction. The decrease in the average peak velocity from 4 to 10 minutes associated with vertical steal and combined with a coronary flow reserve of < 1.6 had a high predictive value for myocardial ischemia in patients with or without prior myocardial infarction.

Aged↗

PubMed1997

Possible role of P-450 metabolite of arachidonic acid in vasodilator mechanism of angiotensin II type 2 receptor in the isolated microperfused rabbit afferent arteriole.

Although angiotensin II type 2 (AT2) receptor has recently been cloned, its functional role is not well understood. We tested the hypothesis that selective activation of AT2 receptor causes vasodilation in the preglomerular afferent arteriole (Af-Art), a vascular segment that accounts for most of the preglomerular resistance. We microperfused rabbit Af-Arts at 60 mmHg in vitro, and examined the effect of angiotensin II (Ang II; 10(-11)-10(-8) M) on the luminal diameter in the presence or absence of the Ang II type 1 receptor antagonist CV11974 (CV; 10(-8) M). Ang II was added to both the bath and lumen of preconstricted Af-Arts. Ang II further constricted Af-Arts without CV (by 74+/-7% over the preconstricted level at 10(-8) M; P < 0.01, n = 7). In contrast, in the presence of CV, Ang II caused dose-dependent dilation; Ang II at 10(-8) M increased the diameter by 29+/-2% (n = 7, P < 0.01). This dilation was completely abolished by pretreatment with an AT2 receptor antagonist PD123319 (10(-7) M, n = 6), suggesting that activation of AT2 receptor causes vasodilation in Af-Arts. The dilation was unaffected by inhibiting either nitric oxide synthase (n = 7) or cyclooxygenase (n = 7), however, it was abolished by either disrupting the endothelium (n = 10) or inhibiting the cytochrome P-450 pathway, particularly the synthesis of epoxyeicosatrienoic acids (EETs, n = 7). These results suggest that in the Af-Art activation of the AT2 receptor may cause endothelium-dependent vasodilation via a cytochrome P-450 pathway, possibly by EETs.

8,11,14-Eicosatrienoic Acid↗

PubMed1997

A new predictor of restenosis after successful percutaneous transluminal coronary angioplasty in patients with multivessel coronary artery disease.

With the goal of improving prediction of restenosis after percutaneous transluminal coronary angioplasty (PTCA) for multivessel coronary artery disease (CAD), we evaluated the usefulness of serial exercise treadmill tests. We previously reported that an increase in the deltaST/delta heart rate (HR) index at follow-up over the value obtained several days after PTCA was useful for detecting restenosis following PTCA for 1-vessel CAD. In that report, comparison of the deltaST/deltaHR index was made based on measurements from the lead disclosing the greatest ST displacement before PTCA. This method was not applicable to patients with multivessel CAD. Seventy-eight patients with multivessel CAD before and several days after PTCA and just before follow-up performed exercise treadmill tests. Simple HR-adjusted indexes of ST-segment depression during exercise (deltaST/deltaHR index) and the sum of the deltaST/deltaHR index in leads II, III, aVF, V4, V5, and V6 (sigma deltaST/deltaHR index) were determined. We compared the predictive power of an increase in sigma deltaST/deltaHR index at follow-up with that of a positive exercise treadmill test and a positive thallium scintigram for restenosis. At follow-up, 37 of the 78 patients showed restenosis. The sigma deltaST/deltaHR index had increased in 30 of these 37 patients (81%), and in 12 of the 41 patients (29%) without restenosis. An increase in sigma deltaST/deltaHR index had a significantly higher sensitivity than the other methods and a significantly higher specificity than a positive exercise treadmill test.

Aged↗

PubMed1997

Assessment of blood flow in the small intestine by laser Doppler flowmetry: comparison of healthy small intestine and small intestine in Crohn's disease.

Blood flow and blood distribution were investigated in 40 patients with normal small intestine and the relation between blood flow and the morphological features of Crohn's disease was examined in 11 patients with Crohn's disease by laser Doppler flowmetry from the serosal side during surgery. In normal small intestine, blood flow was measured at six points: upper, middle, and lower small intestine, each of the mesenteric borders, and the antimesenteric surface. In Crohn's disease, macroscopically normal tissue and affected lesions were observed in detail by intraoperative endoscopy after blood flow measurement. The blood flow values in the normal small intestine gradually decreased from the upper to the lower small intestine. As the level of inflammation progressed in Crohn's disease the blood flow values gradually decreased; the exudative stage of Crohn's disease (aphthoid ulcer) showed blood flow values that were slightly below those in macroscopically normal tissue. These results are the first to demonstrate decreased blood flow in affected lesions in Crohn's disease and changes in blood flow according to the degree of inflammation in vivo.

Adolescent↗

PubMed1997

Use of the QRS scoring system in the early estimation of myocardial infarct size following reperfusion.

While the QRS scoring system has been established as a convenient tool for estimating infarct size in nonreperfused patients during the chronic stage of myocardial infarction, its applicability to reperfused patients in the acute stage has not been established. To investigate whether infarct size could be estimated by the QRS scoring system soon after reperfusion, we evaluated QRS scores obtained serially 6 hours to 1 month after reperfusion, total creatine kinase release, and left ventricular ejection fraction in 126 patients with acute myocardial infarction who underwent successful reperfusion therapy. A significant correlation was observed between the QRS score obtained after 6 hours and that obtained after 1 month (r = .89). The QRS scores obtained after 6 hours and 1 month were significantly correlated with total creatine kinase release (r = -.65 and r = -.75, respectively) and left ventricular ejection fraction (r = .62 and r = .76, respectively). Thus, the QRS scoring system can be used as a simple and economical method for estimation of infarct size soon after reperfusion.

Aged↗

PubMed1997

A superfemale with primary Sjögren's syndrome which involved systemic organs.

A 52-year-old Japanese woman complicated by a sex chromosomal anomaly as a superfemale, a mosaic of XXXXX/XXXX/XXX/XX/XO, with mild mental retardation, was hospitalized for dry mouth, dry eyes, and proteinuria. The sialography of the right parotid gland showed a globular-type gland enlargement. A definite diagnosis of primary Sjögren's syndrome (SS) was made, and further examinations revealed not only typical sicca syndrome but also systemic extraglandular lymphocytic infiltration; interstitial pneumonitis, glomerular- and interstitial nephritis, superficial gastritis, thyroiditis, and a severe excitation conductive impairment of heart. We report a very rare case of superfemale with primary SS which involved systemic organs.

Bronchi↗

PubMed1997

Serum levels of cardiac troponin I and troponin T in estimating myocardial infarct size soon after reperfusion.

BACKGROUND: Cardiac troponin I (TnI) and troponin T (TnT) are highly specific myocardial markers. OBJECTIVE: To determine whether their serum levels can be used to estimate myocardial infarct size soon after reperfusion. METHODS: We measured the serum levels of TnI, TnT, and creatine kinase every 3 h, and the serum cardiac myosin light chain I (MLCI) every 24 h, in 42 patients with acute myocardial infarction in whom reperfusion therapy had successfully been performed. We calculated the severity of regional hypokinesis by analyzing the follow-up ventriculograms with the centerline method. RESULTS: The time from reperfusion to the peak level for TnI was 6.1 +/- 3.5 h, significantly shorter than those for creatine kinase (7.5 +/- 4.1 h) and MLCI (55 +/- 28 h). The time to peak level for TnT (6.8 +/- 4.0 h) differed significantly from that for MLCI but not from that for creatine kinase. There was a significant correlation between the peak levels of TnI and TnT (r = 0.86). The peak TnI and TnT levels were correlated well to the peak creatine kinase level (r = 0.67 and 0.69, respectively), total creatine kinase release (r = 0.66 and 0.66), and the peak MLCI level (r = 0.71 and 0.80). We observed excellent correlations between the peak levels of TnI and TnT, and regional hypokinesis (r = -0.84 and -0.85, respectively). These were comparable to the correlations between regional hypokinesis and the peak creatine kinase level (r = 0.75), total creatine kinase release (r = -0.72), and the peak MLCI level (r = -0.76). CONCLUSIONS: These results suggest that the peak serum levels of TnI and TnT in patients with successful reperfusion are accurate and early indices of infarct size.

Angioplasty, Balloon, Coronary↗

PubMed1997

[Crescentic glomerulonephritis in a patient with rheumatoid arthritis].

A 56-year-old female with rheumatoid arthritis was admitted because of bilateral hip pain. In a few months of her hospitalization, a relatively abrupt renal dysfunction was emerged besides complement breakdown, and renal biopsy revealed crescentic glomerulonephritis. Immunofluorescence study showed peripheral granular deposits of IgG, IgM, and C3 in the glomeruli. Cresents were predominantly composed of macrophages and glomerular epithelial cells. Amyloid nephropathy, renal vasuculitis, and association of other collagen vascular diseases were negligible for the causative factor. It was suggested that immune complexes were formed in the glomeruli, in which both humoral and cellular immune responses were to be induced, that brought cescents formation in the lesions. Crescentic glomerulonephritis in patients with rheumatoid arthritis is rare and a possible pathogenetic mechanisms involved in the development of renal dysfunction are discussed with the special reference to immune complex-induced inflammation.

Antigen-Antibody Complex↗

PubMed1997

Beclomethasone dipropionate administration via cecostomy in ulcerative colitis.

Beclomethasone dipropionate was administered via a cecostomy to four patients with active ulcerative colitis that was refractory to conventional glucocorticosteroid therapy. From a tube cecostomy, beclomethasone dipropionate solution was administered continuously throughout the day. Clinical manifestations, laboratory examinations, and endoscopic and/or radiographic findings markedly improved within 1-2 wk. A serial decrease in the index of disease activity was observed from the time administration began (mean score, 226.0) to 2 wk later (137.4 points). An excellent clinical response was recognized without any significant side effects, and the urgent need for total colectomy was avoided in all four patients.

Adult↗

PubMed1997

Heterogeneity of angiotensin action in renal circulation.

Reported concentrations of angiotensin II (Ang II) in renal interstitial fluid are as high as 10 nM. Despite such high concentrations, intrarenal arterial infusion of Ang II at rates that induce far less change in renal Ang II concentration still elicits renal vasoconstriction. We examined whether the glomerular afferent arterioles (Af-Art) was more sensitive to intraluminal than extraluminal Ang II in superficial or juxtamedullary nephrons. Rat superficial Af-Arts with the intact glomerulus were microdissected and perfused in vitro at 70 mmHg, while juxtamedullary Af-Arts were visualized in isolated perfused kidneys (at 100 mm Hg) according to the method of Casellas and Navar. Increasing doses of Ang II (1 pM to 10 nM) or norepinephrine (NE; 1 nM to 1 microM) were added to either bath (extraluminal) or arteriolar perfusate (intraluminal). Decreases in luminal diameter induced by Ang II were significantly larger with intraluminal than extraluminal administration in superficial Af-Art: at 100 pM the diameter decreased by 52 +/- 8% (N = 6) and 7 +/- 3% with intraluminal and extraluminal administration, respectively. In contrast, in the juxtamedullary Af-Arts intraluminal and extraluminal Ang II caused similar constriction. On the other hand, there was no difference in intraluminal versus extraluminal NE action in either superficial or juxtamedullary nephrons. In conclusion, glomerular Af-Arts seem to have a higher sensitivity to luminal than interstitial Ang II in superficial but not juxtamedullary nephrons. Such heterogeneities in Ang II action may be important in the control of glomerular hemodynamics under various physiological and pathological conditions.

Angiotensin II↗

PubMed1997

Function of angiotensin II type 2 receptor in the postglomerular efferent arteriole.

The balance of vasucular tone between afferent (Af-Art) and efferent arterioles (Ef-Art) is a critical determinant of the glomerular hemodynamics. We recently reported that selective activation of angiotensin II type 2 receptor (AT-2R) causes dilation in the Af-Art. However, the functional role of AT-2R in the Ef-Art has not been defined. In the present study, we microperfused rabbit Ef-Art in vitro, and examined the effect of angiotensin II (Ang II; 10(-11) to 10(-8) M) on the luminal diameter in the presence or absence of an AT-2R antagonist PD123319 (PD; 10(-7) M). Angiotensin II caused dose-dependent constriction in Ef-Arts, with a significant constriction occurring at 10(-11) M; at 10(-10) M the diameter decreased by 28 +/- 4% (N = 6). Pretreatment with PD significantly (P < 0.0125) augmented vasoconstrictor action of Ang II; at 10(-10) M the diameter decreased by 44 +/- 4% (N = 6). We then examined whether blockade of Ang II type 1 receptor (AT-1R) uncovers vasodilator action of Ang II mediated by AT-2R. Efferent arterioles were preconstricted by about 40% with norepinephrine and AT-1R was blocked with its selective antagonist CV11974 (CV; 10(-8) M). Angiotensin II added to preconstricted and CV-pretreated Ef-Arts caused a dose-dependent dilation; at 10(-8) M diameter increased by 28 +/- 3% (N = 5). The dilation was completely abolished by simultaneous pretreatment with PD (N = 4). Our results demonstrate that in the Ef-Art selective activation of AT-2R causes vasodilation, which opposes the vasoconstrictor action of Ang II.

Angiotensin II↗