Biomedical subjects

K Hiwada

Publications and source records attributed to K Hiwada.

At least 181 records · Page 10Linked to original sources

PubMed1995

Left ventricular mass index negatively correlates with heart rate variability in essential hypertension.

To investigate the relationship between alterations of the autonomic nervous activity and left ventricular mass index in essential hypertensive patients, 24-h power spectral analysis of R-R intervals was performed using Holter electrocardiography. Fifty-three patients (mean age, 58.0 +/- 13.1 years; 30 men and 23 women) participated. The urinary excretions and plasma levels of catecholamines were also determined. Power spectral analysis of R-R interval was performed every 10 min by the maximum entropy method to obtain the low frequency band (LFB; 0.04 to 0.15 Hz), which is an index of both parasympathetic and sympathetic nervous activities, and the high frequency band (HFB; 0.15 to 0.4 Hz), which reflects parasympathetic nervous activity. LFB and HFB were averaged every hour to obtain hourly LFB and HFB levels. Total LFB and HFB were calculated as the summation of 24-h LFBs and HFBs. Left ventricular mass index showed a significant negative correlation with total LFB (r = -0.466, P < .001) and total HFB (r = -0.319, P < .02). These findings suggest that the level of end-organ damage correlates with neuronal alteration in essential hypertension.

Autonomic Nervous System↗

PubMed1995

Evaluation of serum KL-6 levels in patients with pulmonary tuberculosis.

SETTING: KL-6, a human MUC-1 mucin preferentially expressed on type II pneumocytes, is a sensitive serum marker for evaluating alveolar damage of interstitial pneumonia and pulmonary fibrosis. Some patients with pulmonary tuberculosis develop severe respiratory dysfunction caused by extensive pulmonary fibrosis, compensatory emphysema and fibrous pleural thickening. OBJECTIVE: To evaluate the clinico-pathological significance of KL-6 in pulmonary tuberculosis. DESIGN: Serum KL-6 levels were measured in sera from 57 patients with active pulmonary tuberculosis and 38 healthy controls by a sandwich-type enzyme-linked immunosorbent assay. Immunohistochemistry was performed by an avidin-biotin-peroxidase complex method. RESULTS: KL-6 levels were significantly higher in the patients than in the healthy controls (518 +/- 693 [SD] vs 227 +/- 91 U/ml, P < 0.001) and increased significantly according to the extent of pulmonary lesions evaluated by chest X-ray (P < 0.001). There was a significant negative correlation between serum KL-6 levels and % vital capacity (VC) (r = 0.642, P < 0.05). KL-6 was strongly expressed on proliferated type II pneumocytes and cuboidal epithelial cells adjacent to thickened intralobular septa and pleura. CONCLUSIONS: In pulmonary tuberculosis, serum KL-6 originates from proliferated type II pneumocytes and cuboidal epithelial cells, and is a useful marker presenting the degree and extent of pulmonary fibroproductive lesions.

Aged↗

PubMed1995

Increased secretion of atrial and brain natriuretic peptides during acute myocardial ischaemia induced by dynamic exercise in patients with angina pectoris.

1. This study was conducted to assess the role of artrial and brain natriuretic peptides during acute myocardial ischaemia associated with dynamic exercise. 2. Study subjects consisted of 35 angiographically proven patients with angina pectoris and 35 angiographically normal control subjects. All subjects underwent 201Tl dynamic exercise testing. The presence and localization of the exercise-induced acute myocardial perfusion defect were assessed by 201Tl single-photon emission computed tomography. The severity score was calculated using the early image for quantitative assessment of the acute myocardial perfusion defect. 3. Plasma levels of atrial natriuretic peptide increased from 21.3 +/- 3.8 to 72.2 +/- 26.7 pg/ml (P < 0.01) in the angina pectoris group, and increased from 19.4 +/- 2.4 to 36.4 +/- 17.4 pg/ml (P < 0.01) in the control group during dynamic exercise. Plasma levels of brain natriuretic peptide increased from 2.8 +/- 0.8 to 6.9 +/- 2.6 pg/ml (P < 0.01) in the angina pectoris group, but did not change significantly in the control group (from 2.7 +/- 0.7 to 2.9 +/- 1.0 pg/ml) during dynamic exercise. At peak exercise, plasma levels of these natriuretic peptides in the angina pectoris group were significantly higher than those in the control group (P < 0.01). 4. At peak exercise, there were correlations between the plasma level of atrial natriuretic peptide and heart rate in both the angina pectoris and control groups (P < 0.01, r = 0.46; P < 0.01, r = 0.51, respectively), but no significant correlations between the plasma level of brain natriuretic peptide and heart rate in either group. The plasma levels of these peptides at peak exercise correlated well with the severity score in the angina pectoris group (atrial natriuretic peptide, r = 0.71, P < 0.01; brain natriuretic peptide, r = 0.69, P < 0.01).

Acute Disease↗

PubMed1995

Ubenimex activates the E-cadherin-mediated adhesion of a breast cancer cell line YMB-S.

It has been reported that ubenimex, a biological response modifier, has a direct anti-tumor effect. To clarify the mechanism involved, we examined the effects of ubenimex on the growth and adhesive property of a breast cancer cell line YMB-S. The cells proliferate in a floating manner without aggregation in normal complete medium. Ubenimex induced cell-cell and cell-surface adhesion of the cells accompanied with growth suppression. E-Cadherin localized at cell-cell contact sites of adhered cells, and anti-E-cadherin antibody inhibited the adhesion. Both Western blot analysis and binding assay disclosed that there was no apparent difference between E-cadherin levels of the cells before and after the treatment with ubenimex. These results indicate that ubenimex inhibits the proliferation of YMB-S cells and augments cell-to-cell adhesion through the induction of E-cadherin-mediated adhesion resulting from the functional activation of pre-expressed but inefficient E-cadherin.

Antibiotics, Antineoplastic↗

PubMed1995

Evaluation of soluble IL-6 receptor concentration in serum and epithelial lining fluid from patients with interstitial lung diseases.

We measured soluble IL-6 receptor (sIL-6R) levels in serum and bronchoalveolar lavage fluids (BALF) from patients with interstitial pneumonia of unknown etiology (IP) (n = 17), sarcoidosis (n = 8) and normal control subjects (n = 10), to investigate its role in pulmonary diseases. Soluble IL-6R was determined by an ELISA. The volume of epithelial lining fluid (ELF) in BALF was estimated using an urea method. We found that levels of sIL-6R in serum, BALF, and ELF from patients with IP or sarcoidosis were significantly higher than those from normal subjects. Furthermore, levels of sIL-6R in BALF or ELF were significantly correlated with those of albumin, indicating that sIL-6R, together with albumin, may enter ELF as a result of the increased permeability caused by pulmonary inflammation. Thus most of the sIL-6R in ELF would be from serum, and relatively small amounts of it might be produced locally. However, sIL-6R levels in ELF, but neither serum nor BALF, were significantly correlated with levels of C-reactive protein in patients with IP. These results suggest that both systemic and local production of sIL-6R are increased, and raised sIL-6R is involved in the modulation of systemic and local inflammatory responses in patients with IP and sarcoidosis.

Adult↗

PubMed1995

Blood pressure response to the Valsalva maneuver in pheochromocytoma and pseudopheochromocytoma.

To elucidate whether a difference in blood pressure reactivity exists between patients with pheochromocytoma (n = 8) and pseudopheochromocytoma (n = 22), we evaluated blood pressure changes during a Valsalva maneuver and baroreceptor reflex sensitivity. We also examined the effects of propranolol and prazosin on blood pressure reactivity during a Valsalva maneuver in patients with pseudopheochromocytoma. Pseudopheochromocytoma was defined as a paroxysmal rise in blood pressure accompanying pheochromocytoma-like symptoms and normal catecholamine values. The difference in systolic blood pressure between phase IV of the Valsalva maneuver and baseline (delta SBP) was markedly smaller in the pheochromocytoma patients (8.4 +/- 18.4 mm Hg) than in the essential hypertension patients (n = 30, 30.9 +/- 19.4 mm Hg) and normotensive control subjects (n = 10, 31.3 +/- 11.4 mm Hg), whereas delta SBP in the pseudopheochromocytoma patients (77.8 +/- 11.2 mm Hg) was markedly greater than in the other three groups. delta SBP was markedly suppressed by the administration of both propranolol and prazosin. Baroreceptor reflex sensitivity index was lower in the pheochromocytoma group than in the other three groups. In conclusion, blood pressure reactivity responses to a Valsalva maneuver are disparate between pheochromocytoma and pseudopheochromocytoma. The high blood pressure reactivity to a Valsalva maneuver in pseudopheochromocytoma is due to hyperactivity in both beta- and alpha 1-adrenergic receptor functions, and the low blood pressure reactivity to a Valsalva maneuver in pheochromocytoma seems to be mainly due to the desensitization of both adrenergic systems associated with chronic catecholamine excess. In addition, the impaired baroreceptor function in pheochromocytoma is partially responsible for it.

Adrenal Gland Neoplasms↗

PubMed1995

Autonomic nervous function in non-dipper essential hypertensive subjects. Evaluation by power spectral analysis of heart rate variability.

Autonomic nervous function was evaluated by means of power spectral analysis of heart rate variability in hospitalized dipper (n = 31) and non-dipper (n = 31) essential hypertensive subjects. Twenty-four-hour blood pressure (BP) measurement was performed by the cuff-oscillometric method to evaluate the nocturnal decrease of BP. The non-dipper subjects were defined as those whose nocturnal decrease of systolic BP was < 10% of daytime BP. Power spectral analysis of RR interval was performed from Holter ECG every 10 minutes by the maximum entropy method to obtain the low-frequency band (LFB, 0.04 to 0.15 Hz), which is an index of both parasympathetic and sympathetic nervous activities, and the high frequency band (HFB, 0.15 to 0.4 Hz), which reflects parasympathetic nervous activity. LFB and HFB were averaged every hour to obtain hourly LFB and HFB values. Total LFB and total HFB were calculated as the mean values of 24 hourly averaged LFBs and HFBs. Both LFB and HFB were significantly lower in non-dipper hypertensives than in dipper subjects throughout the day. In dipper hypertensives, LFB showed a nocturnal decrease, whereas HFB was significantly increased during the nighttime. However, these diurnal changes in LFB and HFB were significantly blunted in non-dipper subjects. These findings indicate that non-dipper hypertensive subjects were characterized with a decreased physiological circadian fluctuation on autonomic functions compared with dipper subjects. This alteration in the autonomic nervous function may explain the non-dipper phenomenon in essential hypertension.

Autonomic Nervous System↗

PubMed1995

Circulating interleukin-6 levels in patients with bronchial asthma.

Circulating interleukin-6 (IL-6) levels were determined using a sensitive enzyme immunoassay in adults with asthma in stable condition during naturally occurring attacks and before and after allergen inhalation tests. IL-6 was significantly elevated even in asymptomatic asthmatic subjects (n = 17) compared with normal control subjects (n = 17). During naturally occurring asthmatic attacks, serum IL-6 levels were significantly elevated in comparison with those in a symptom-free condition (4 wk interval; n = 8, p < 0.01). No significant difference was observed in serum IL-6 levels obtained from control asymptomatic asthmatic subjects during the period (n = 10). There was a significant elevation in circulating IL-6 levels in eight asthmatic patients following inhalation of allergen but not methacholine. These results suggest that IL-6 is involved in the pathophysiology of bronchial asthma.

Adult↗

PubMed1995

Acute effect of glyceryl trinitrate on systolic blood pressure and other hemodynamic variables.

The acute effect of glyceryl trinitrate (GTN) is mainly the reduction of systolic blood pressure (SBP) rather than diastolic blood pressure (DBP). To examine the mechanisms for decrease in SBP by GTN, the authors measured arterial compliance (AC), cardiac output (CO), stroke volume (SV), pulmonary capillary wedge pressure, right ventricular end-diastolic pressure, right atrial pressure, and left ventricular end-diastolic pressure before and after administration of GTN. Fourteen patients who underwent cardiac catheterization were included in this study. The change of each variable was estimated by the differences between values just before and at three minutes after GTN. After administration of GTN, SBP was significantly decreased from 158 +/- 21 to 138 +/- 12 mmHg (P < 0.01). AC was significantly increased, and pulmonary capillary wedge pressure, CO, and SV were significantly decreased. The change in SBP was inversely correlated with the change in AC and positively correlated with the change in CO or SV. The authors conclude that the mechanism for decrease in SBP by GTN is associated with both an increase in AC and a decrease in venous return.

Administration, Sublingual↗

PubMed1995

Noninvasive physiological assessment of vascular wall sclerosis using carotid pulse tracing and cine magnetic resonance.

In order to evaluate vascular wall sclerosis, the authors compared parameters of carotid pulse tracing with ascending aortic wall distensibility by using cine magnetic resonance (MR). Cine MR and carotid pulse tracing were performed in 20 healthy volunteers (mean age fifty-six years). They measured the interval from aortic second heart sound (A2) to the dicrotic notch (DN) (A2-DN interval), and the height from dicrotic notch to top/total height of carotid pulse tracing (b/a ratio). Ascending aortic distensibility was calculated from the following formula: max area - min area/min area x pulse pressure. There were significant positive correlations (r = 0.70) between the A2-DN interval and ascending aortic distensibility and between b/a ratio and ascending aortic distensibility (r = 0.63). The measurement of A2-DN interval and b/a ratio using carotid pulse tracing is a useful method for assessing ascending aortic wall sclerosis.

Adult↗

PubMed1995

Relation between postpacing T wave changes and myocardial scintigraphic characteristics in patients with ventricular demand pacemaker.

The aim of this study was to elucidate the cause of T wave changes after ventricular pacing using thallium 201 single photon emission computed tomography (Tl-SPECT). Tl-SPECT was performed in 20 patients with sick sinus syndrome who had negative T wave after ventricular pacing and had had a ventricular demand pacemaker (VVI) implanted. Patients who have stenotic coronary arteries were excluded from the study. From the analysis of Tl-SPECT, extent score was calculated as the ischemic region. Data in patients with SSS were compared with those in 20 normal controls (NC). Thallium perfusion defects in patients with VVI were observed and distributed mainly in apex and inferior regions on the polar map. The extent score in patients with VVI was significantly higher than that in NC (56.4 +/- 21.6% vs 3.2 +/- 6.4%, P < 0.01). The washout rate of thallium 201 in the defect area was significantly lower in patients with VVI than in NC (27.4 +/- 10.2% vs 46.8 +/- 12.3%, P < 0.01). These results suggest that T wave changes after ventricular pacing are closely related to myocardial ischemia.

Aged↗

PubMed1995

Mechanism of atrial fibrillation and increased incidence of thromboembolism in patients with hypertrophic cardiomyopathy.

To elucidate the morphologic characteristics of the left ventricle in patients with hypertrophic cardiomyopathy who developed atrial fibrillation, we studied left ventricular geometry by two-dimensional echocardiography in 92 patients with hypertrophic cardiomyopathy. These patients were divided into two groups; 24 patients with transient or persistent atrial fibrillation (group I) and 68 patients with sinus rhythm (group II). Left ventricular chamber size in group I was significantly smaller than that in group II. Left ventricular chamber size was correlated positively with stroke volume, and was correlated negatively with left ventricular end-diastolic pressure. The incidence of systemic thromboembolism in group I was 7.1% per patient year. In hypertrophic cardiomyopathy, the size of the left ventricle appears to have major pathophysiologic significance in the development of atrial fibrillation. In addition, since patients with hypertrophic cardiomyopathy who develop atrial fibrillation have a potential risk of systemic thromboembolism, prophylactic anticoagulant therapy should be performed in these patients.

Adult↗

PubMed1995

Augmented secretion of atrial and brain natriuretic peptides during dynamic exercise in patients with old myocardial infarction.

To assess the role of atrial and brain natriuretic peptides (ANP, BNP) in maintaining cardiac performance at rest and during exercise in patients with cardiac dysfunction, we measured plasma levels of ANP and BNP during 201Tl dynamic exercise testing in 32 patients with angiographically proven old myocardial infarction (OMI) and 35 normal control subjects (CS). Plasma levels of ANP and BNP at rest were significantly higher in patients with OMI than in CS (ANP, 42.6 +/- 19.3 vs 19.4 +/- 2.4 pg/ml, p < 0.01; BNP, 53.4 +/- 32.5 vs 2.8 +/- 0.8 pg/ml, p < 0.01, respectively). Correlations were found between plasma levels of these peptides and left ventricular ejection fraction (LVEF), cardiac index (CI), pulmonary capillary wedge pressure (PCWP) and left ventricular end-diastolic pressure (LVEDP) in patients with OMI. In addition, a strong positive correlation was found between plasma levels of these peptides and the severity score obtained from 201TI myocardial scintigraphy. During exercise, both ANP and BNP significantly increased in patients with OMI. However, in CS, although ANP increased, BNP remained unchanged. The changes in plasma levels of ANP or BNP from at rest to peak exercise correlated with LVEF, CI, PCWP, LVEDP and the severity score in patients with OMI. These findings indicate that ANP and BNP play an important role in maintaining cardiac performance at rest and during exercise in patients with cardiac dysfunction.

Adult↗

PubMed1995

Left ventricular geometry and cardiac function in mild to moderate essential hypertension.

To elucidate left ventricular (LV) cardiac structure and function in patients with mild to moderate essential hypertension, we studied the relationship between LV geometry and function. We evaluated LV diastolic and systolic functions by M-mode echocardiography in 91 age-matched normotensive control subjects (NT) and 124 patients with essential hypertension. Hypertensive patients were divided into two groups based on the WHO stage classification: WHO I (n = 76) and WHO II (n = 48). Patients in WHO I and WHO II were further categorized according to the relative wall thickness as normal left ventricle (n = 47), concentric remodeling (n = 29), concentric hypertrophy (n = 25), and eccentric hypertrophy (n = 23). LV diastolic function was significantly decreased in the hypertensive groups compared to NT. There was no significant difference in LV systolic performance among NT, WHO I and WHO II. LV contractility was significantly increased in WHO I compared to NT. In respect to ventricular geometric pattern, LV diastolic function was significantly decreased in both the concentric hypertrophy and eccentric hypertrophy groups. LV systolic dysfunction was noted only in the eccentric hypertrophy group. In conclusion, patients with concentric remodeling had normal systolic and diastolic functions. LV diastolic function was impaired in both the concentric and eccentric hypertrophy groups due to an increase in LVMi. Moreover, LV systolic impairment was noted in the eccentric hypertrophy group due to an inappropriate compensation to LV systolic load.

Adult↗

PubMed1995

IgG and IgM rheumatoid factor levels parallel interleukin-6 during the vasculitic phase in a patient with Churg-Strauss syndrome.

A 43-year-old woman with a 10-year history of bronchial asthma developed marked peripheral blood eosinophilia and symptoms of vasculitis. A diagnosis of Churg-Strauss syndrome (CSS) was made, and her symptoms were successfully treated with low-dose prednisolone. Serum rheumatoid factors (RF) of both IgG and IgM, but not IgA or IgE, subclasses transiently appeared in accordance with the vasculitic phase. Serum interleukin-6 (IL-6) levels also transiently increased in this phase and the peak level was reached just prior to the maximum of RF elevation, suggesting the role of IL-6 as an inducer of RF. RF and IL-6 seemed to be involved in the pathogenesis of the vasculitis in this patient.

Adult↗

PubMed1995

Warfarin-induced eosinophilic pleurisy.

A 51-year-old man was admitted to our hospital because of dry cough and low grade fever with right-sided pleural fluid and blood eosinophilia. Warfarin had been prescribed following coronary artery bypass grafting. After the discontinuation of warfarin the clinical and chest X-ray findings improved; readministration of the drug caused recurrent blood eosinophilia and pleural effusion in the other lung. Since no other specific etiologies for eosinophilia and pleural effusion were determined by extensive evaluation, warfarin seemed to be associated with his illness. This is the first report of warfarin-induced eosinophilic pleurisy.

Anticoagulants↗

PubMed1995

[A case of chylothorax caused by mesenteric panniculitis].

A 76-year-old female was referred to our hospital for examination of milky pleural effusion. We diagnosed her illness as chylothorax because of the high concentration of triglyceride in the effusion. There was neither obstruction nor damage of the thoracic duct. Systemic evaluation disclosed an abdominal mass in the umbilical region. Fasting with intravenous hyperalimentation followed by pleurodesis with minocycline successfully eliminated the effusion. On the other hand, the abdominal mass was diagnosed as mesenteric panniculitis by open biopsy. Since she also had chylous ascites, the tumor could have obstructed the intestinal lymphatics. Chylothorax was probably caused by damage to collateral lymph circulation.

Aged↗

PubMed1995

[Influence of aging upon changes in symptoms and cardiac size associated with surgical repair of atrial septal defect in adults].

To elucidate the influence of aging upon the improvement of symptoms and cardiac size associated with surgical repair of atrial septal defect, clinical symptoms, cardiothoracic ratio and hemodynamic variables in older patients (group A; age at operation > or = 50 years old, n = 11) were compared with those in younger patients (group B; age at operation < 50 years old, n = 8). There were no differences in hemodynamic variables, i.e., peak systolic pulmonary pressure, pulmonary to systolic flow ratio (Qp/Qs), pulmonary to systolic vascular resistance ratio (Rp/Rs) and left to right shunt ratio between the two groups. Symptomatic benefits occurred in all patients, although 3 patients in group A who had atrial fibrillation preoperatively still displayed symptoms such as exertional dyspnea. The postoperative (after 3 months) cardiothoracic ratio improved in all patients except for 3 patients in group A who were operated at over 60 years of age. Although there was no significant difference in preoperative cardiothoracic ratio between the two groups, the postoperative cardiothoracic ratio in group B was significantly smaller than that in group A. These results indicate that operative closure of atrial septal defect is recommended for all patients aged 50 years old or older, but early improvement of symptoms and cardiomegaly in older patients is lower than that in younger patients.

Adult↗