Foams stabilized with solid particles carrying stimuli-responsive polymer hairs

Submicrometer-sized polystyrene (PS) particles carrying stimuli-responsive poly[2-(diethylamino)ethyl methacrylate] (PDEA) hairs with degrees of polymerization of 30, 60 and 90 were synthesized by dispersion polymerization and used as a particulate foam stabilizer. The effects of the composition of these PDEA-PS particles and foam formation conditions on foamability, foam stability and foam microstructures were extensively investigated. The hairy particles were found to work as an effective stabilizer of aqueous foams in basic media, in which the PDEA hairs are not protonated and thus the particle surfaces exhibit suitable wettability at the air-water interface. In contrast, little to no foam or unstable foams were formed in acidic aqueous media, in which the hairs are protonated and are therefore water soluble. Particles carrying longer hairs resulted in greater foamability and more highly stabilized foams that were capable of persisting for more than one month. Foams were found to form in a narrower pH range when using PS particles with longer hairs, due to both entropic and image charge effects. Data obtained from the touch mixer mixing method showed that both foamability and foam stability increased with increases in the concentration of polymer particles up to 10 wt%, because higher concentrations allowed greater air-water interfacial areas to be stabilized. Conversely, only minimal foam was obtained at and above 15 wt% because of the high viscosity of the resulting aqueous particle dispersion. Trials using the homogenizer mixing method showed that foam with a cream-like texture could be formed even at 40 wt% particle concentration as a result of the improved mixing efficiency. Defoamation could be induced by exposing the foams to HCl vapor. Exposure to acidic vapor led to in situ protonation of the 2-(diethylamino)ethyl methacrylate residues, rendering the PDEA hairs hydrophilic and water soluble, and desorption of the PDEA-PS particles from the air-water interface.

Abstract P323: Waon Therapy, a Form of Thermal Therapy, Reduces Oxidative Stress Systemically and Inhibits the Progression of Cardiac Dysfunction in TO-2 Cardiomyopathic Hamsters with Heart Failure

Background: Oxidative stress is one of the most crucial factors that develop chronic heart failure (CHF), leading to cardiac apoptosis and fibrosis and vascular endothelial dysfunction. We have reported that Waon therapy, which is a form of thermal therapy using a far infrared-ray dry sauna at 60 degrees centigrade, improves cardiac and vascular endothelial functions and prognosis in patients with CHF. The aim of this study is to investigate whether Waon therapy reduces oxidative stress and prevents from developing cardiac dysfunction in CHF.

Methods: Thirty-week old male TO-2 cardiomyopathic hamsters with CHF were divided into Waon therapy or control group. Waon therapy group underwent Waon therapy daily for 4 weeks. Control hamsters did not take any treatment. We examined the amounts of reactive oxygen species of serum, hearts and aortas using ELISA and immunohistochemistry. We measured left ventricular % fractional shortening (LV%FS), and performed TUNEL and Azan staining of hearts to assess cardiac function, apoptosis and fibrosis, respectively. Anti-oxidants and apoptotic and angiogenetic factors were assessed by Western blot. All examinations were performed after 4 weeks of treatment.

Results: Four-week Waon therapy significantly decreased oxidative stress of serum, hearts and aortas compared to those of controls. Waon therapy significantly increased LV%FS and decreased cardiac apoptosis and fibrosis (LV%FS, Waon therapy: 23.3±4.3 vs. control: 16.5±4.2%, P<0.01, TUNEL positive nuclei, 22.0±2.6 vs. 49.3±7.2%, P<0.01, % fibrosis, 20.6±5.3 vs. 47.6±4.8%, P<0.01). Waon therapy significantly increased the expressions of manganese superoxide dismutase, heat shock protein 27 (HSP27) and HSP32 of hearts and aortas, which negatively modulate oxidative stress, compared to those of controls. Waon therapy significantly increased endothelial nitric oxide synthase and decreased plasminogen activator inhibitor-1 of aortas. In addition, Waon therapy significantly decreased Bax, cleaved caspase 3 and cytochrome c and increased Bcl-2 and hypoxia-inducible factor-1α of the failing hearts.

Conclusions: Waon therapy reduces oxidative stress systemically and inhibits the progression of cardiac dysfuntion in TO-2 cardiomyopathic hamsters.

Time-course of Toll-like receptor 2 expression, as a predictor of recurrence in patients with bacterial infectious diseases

The clinical course of bacterial infectious diseases is often variable, especially in elderly patients. Thus, new biological markers have been sought to predict the disease outcome. Recent studies have revealed that Toll-like receptor (TLR) 2 and/or TLR4 on circulating monocytes are significantly up-regulated in bacterial infections. However, the lack of reliable quantification methods hampers extensive study on the modulation of these molecules in response to the patient's clinical condition. In this study, we developed a new quantitative flow cytometric analysis system for TLR2. We then carried out a longitudinal study on TLR2 expression levels on monocytes from patients suffering from bacterial infectious diseases during and after antibiotic treatment. The clinical outcome divided 37 patients into 'cure' (n = 24) and 'recurrence' (n = 13) groups. A significant difference between the two groups was recognized in the TLR2 levels just after antibiotic treatment (antibody-binding sites/cell, 4395 +/- 784 versus 5794 +/- 1484, P < 0.001). The risk of recurrence was associated significantly with TLR2 (P < 0.001), but not C-reactive protein (P = 0.351) levels assayed during the first remission. Furthermore, antibiotic effectiveness was associated inversely with TLR2 levels during antibiotic administration (P < 0.001). Taken together, TLR2 expression levels on monocytes provide critical information for planning treatment against bacterial infectious diseases.

Comparison of transthoracic Doppler echocardiography and natriuretic peptides in predicting mean pulmonary capillary wedge pressure in patients with chronic atrial fibrillation

The purpose of this study was to assess whether transthoracic Doppler echocardiography and serum natriuretic peptide levels could predict mean pulmonary capillary wedge pressure (PCWP) in patients with chronic atrial fibrillation. We examined mitral flow velocity and pulmonary venous flow (PVF) velocity patterns in 32 patients with chronic atrial fibrillation. Plasma A-type and B-type natriuretic peptide (ANP, BNP, respectively) levels in the peripheral vein were measured. Significant correlations were observed between mean PCWP and the following: peak velocity (r = 0.51) and deceleration time (r = -0.65) of the mitral flow; peak velocity (r = 0.64) and deceleration time (r = -0.80) of the PVF; BNP (r = 0.60); and ANP (r = 0.36). Stepwise multiple linear regression analysis selected PVF deceleration time and mitral flow deceleration time as independent predictors of PCWP. A cutoff value of PVF deceleration time of < or =150 ms and a mitral flow deceleration time of < or =100 ms predicted a mean PCWP of > or =18 mm Hg, with a sensitivity of 100% and 80% and a specificity of 96% and 85%, respectively. In conclusion, PVF deceleration time and mitral flow deceleration time obtained from transthoracic Doppler echocardiography are more accurate predictors of mean PCWP than values obtained with natriuretic peptides in patients with chronic atrial fibrillation.

Resistance of CD4-positive T lymphocytes to etoposide-induced apoptosis mediated by upregulation of Bcl-xL expression in patients with HTLV-I-associated myelopathy

Human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) is characterized by chronic inflammation of the spinal cord. The exact mechanisms that enhance the development of chronic myelopathy remain to be determined. One such mechanism could be an altered response of peripheral blood CD4(+) T lymphocytes to apoptotic stimuli. We examined the sensitivity of these cells to apoptosis in HAM patients and control. Apoptosis was induced by etoposide, which induces mitochondria-dependent apoptosis through the release of cytochrome c from the mitochondria. The percentage of apoptotic cells that expressed hypodiploid DNA among etoposide-treated CD4(+) T lymphocytes was significantly lower in HAM patients than in the control. Western blot analysis of cell lysates derived from CD4(+) T lymphocytes demonstrated that the expression level of Bcl-xL protein was significantly higher in HAM patients than in the control. Our results indicate that peripheral blood CD4(+) T lymphocytes of HAM patients are resistant to apoptosis triggered through mitochondrial death pathway through upregulation of expression of anti-apoptotic protein, Bcl-xL. This phenomenon might contribute to the prolongation and perpetuation of the chronic inflammatory process in the spinal cord of HAM patients.

Monophasic transmitral flow pattern with less increase in heart rate indicates left ventricular dysfunction

When heart rate (HR) increases, mitral flow can become monophasic. Prolonged isovolumic contraction and relaxation time (ICT and IRT), directly related to left ventricular (LV) function, can potentially influence the HR with monophasic mitral flow. The present study investigated the relation between HR that causes monophasic flow and LV function. During diagnostic catheterization, HR was increased using right atrial pacing by 2 beats/min every 2 min in a stepwise manner until the development of monophasic mitral flow in 17 patients with normal sinus rhythm. ICT, IRT, end-diastolic and end-systolic LV volumes, LV ejection fraction, LV peak + and -dP/dt, peak (+dP/dt)/P, and the relaxation time constant (tau) were measured by Doppler echocardiography or catheterization when monophasic mitral flow developed. The monophasic HR varied from 74 to 106 beats/min. By univariate analysis, ICT (p<0.01, r2=0.73), LV peak +dP/dt (p<0.05, r2=0.37), peak (+dP/dt)/P (p<0.01, r2=0.71), peak -dP/dt (p<0.05, r2=0.25), and tau (p<0.05, r2=0.33) had a significant correlation with monophasic HR. By multivariate analysis, prolonged ICT and reduced LV peak -dP/dt independently contributed to monophasic mitral flow with less increase in HR. Monophasic mitral flow with less increase in HR indicates impaired LV systolic and diastolic function during isovolumic contraction and relaxation.

Comparison of various reproductive status in Sika deer (Cervus nippon) using fecal steroid analysis

The feasibility of fecal steroid analysis for pregnancy diagnosis and sex determination were tested in sika deer (Cervus nippon). Feces were collected from captive sika deer in June (non-breeding season and late-pregnancy period) and October (breeding season), and also from the rectum of 24 female sika deer (19 pregnant and 5 non-pregnant females) shot as part of programs for population control in February and March (mid-pregnancy period). In mid- and late-pregnancy periods, fecal progesterone concentrations were significantly higher in pregnant female than in male and non-pregnant female deer. In October, fecal testosterone concentrations were higher in adult male deer, and no difference was found between young males and females. These results suggest that fecal steroid analysis would be a useful means for estimating pregnancy status and for detecting adult male among wild deer.

Retroperitoneal liposarcoma presenting a indirect inguinal hernia

A 60-year-old man was admitted to our hospital with a right inguinal swelling that had been growing in size without any pain for 7 months. We diagnosed the growth as a right inguinal hernia and operated on him. The growth, however, was found to be a tumor it situated along the spermatic cord and testicular vessels. We diagnosed it as a lipoma. The tumor was resected near part of the internal inguinal ring. Histopathological diagnosis showed well-differentiated liposarcoma of the sclerosing type. Postoperative computed tomography (CT) revealed a large residual tumor in the retroperitoneum. We believed that the tumor was a retroperitoneal liposarcoma and that it developed in the inguinal region. The residue of the liposarcoma was resected onto the right inguinal tract. A periodic follow up has been performed and no evidence of recurrence or metastasis has been seen in the 4 years and 9 months since the second surgery. No adjuvant therapy was performed. Inguinal liposarcomas are relatively rare and in most cases these tumors are thought to originate in the spermatic cord. The origin of the tumor is believed to be the retroperitoneum.

Apheresis treatment in Lambert-Eaton myasthenic syndrome

The Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disorder of peripheral cholinergic transmission in which autoantibodies decrease the presynaptic release of acetylcholine at the neuromuscular junction and autonomic system. Recent results suggest that the antibodies to P/Q-type calcium channels are the principal pathogenic factors in LEMS. Here, we present our experience with cases of LEMS who are noncarcinomatous. We studied the efficacy of plasmapheresis, analyzing the clinical score, electrophysiological finding, and the titer of anti-P/Q-type voltage-gated calcium channel (P/Q-VGCC) antibody. The first case, a 72-year-old female presenting with leg weakness, was treated by plasma exchange (PE). However, clinical improvement was transient; intravenous immunoglobulin (IVIg) therapy was followed by additional PE. She had a clinical and electromyologic improvement, and her P/Q-VGCC antibody titers decreased. Her clinical status and CMAP amplitude correlated closely with the anti-P/Q-VGCC antibody titers. The second case, a 73-year-old male presenting with leg weakness, was treated by PE and double-filtration plasmapheresis. The P/Q-VGCC antibody titres decreased immediately after these aphereses, but recovered to the pretreatment levels 1 week after them. After the immunosuppressive drugs prednisolone and azathioprine were started, his clinical symptoms improved. His antibody titers decreased gradually after immunosuppressive therapy. It is speculated that no sufficient efficacious improvement could be obtained by apheresis alone because of a high rate of P/Q-VGCC antibody production. Considering our experiences and other literature, we discuss the indication of apheresis treatment of LEMS.

Sex determination based on fecal DNA analysis of the amelogenin gene in sika deer (Cervus nippon)

A sex determination method using DNA extracted from feces has been developed for sika deer (Cervus nippon). We determined a partial sequence of the amelogenin gene of sika deer, which exists on both X and Y chromosomes with a deletion region on the Y chromosome. Based on the sexually dimorphic sequences, we designed a pair of primers which could amplify DNA fragments the lengths of which are different between males and females. PCR products were detected in 34 out of 37 fecal samples collected from captured deer and the sexes estimated by the present method were perfectly matched with the actual sexes.

Attenuated coronary flow reserve and vascular remodeling in patients with hypertension and left ventricular hypertrophy

OBJECTIVES

The purpose of this study was to evaluate the association between hypertension and left ventricular hypertrophy (LVH) with both coronary vascular remodeling and endothelial function.

BACKGROUND

The association between endothelial and nonendothelial coronary flow reserve with vascular remodeling in patients with hypertension and LVH is still unclear.

METHODS

One hundred and eleven patients with normal or mildly diseased coronary arteries at angiography underwent intravascular ultrasound examination of the left anterior descending coronary artery. Patients were divided into three groups: group 1: n = 13, hypertensive patients with LVH; group 2: n = 30, hypertensive patients without LVH; group 3: n = 68, normotensive patients. Vessel and lumen area and atherosclerotic plaque area were evaluated. Vascular reactivity was examined using intracoronary adenosine and acetylcholine.

RESULTS

Vessel area in group 1 (with LVH) was significantly (p < 0.01) greater than that in group 2 (without LVH), whereas, vessel area in both groups 1 and 3 was similar (12.8 +/- 0.8 mm2, 10.7 +/- 0.4 mm2 and 11.5 +/- 0.3 mm2). Coronary blood flow at baseline for patients in group 1 (with LVH) was significantly greater than it was for patients in groups 2 and 3 (81.1 +/- 9.9 ml/min, 56.5 +/- 6.2 ml/min and 48.1 +/- 3.2 ml/min, both p < 0.05). In comparison with groups 2 and 3, the response to both acetylcholine and adenosine was significantly impaired in patients with LVH.

CONCLUSIONS

The current study demonstrates that hypertension with LVH is associated with both coronary vascular remodeling and attenuated endothelial and nonendothelial coronary flow reserve.

[Juvenile cerebral infarction associated with heparin cofactor II abnormality. A case report]

A 15-year-old woman with a history of transient dysarthria two years before, suddenly developed weakness of right upper extremity, right facial palsy, and dysarthria. She was admitted to our hospital on the third day. She had no hypertension, heart murmur and oedema. On neurological examination, she had mild right hemiparesis including face muscles and mild dysarthria. The right knee jerk was brisk with no Babinski's sign. Ataxia and sensory disturbance were not present. T2-weighted MRI showed a hyperintensity at the posterior limb of the left internal capsule. Cerebral angiography was unremarkable. Ultracardiography and 24-hour electrocardiography were normal. Laboratory data revealed no inflammatory findings, liver dysfunction, hyperglycemia and hyperlipidemia. Antinuclear and anticardiolipin antibodies were negative. Prothrombin time was normal, but activated partial thromboplastin time was slightly prolonged (35.4 sec, normal 25.2-34.4). Protein C, protein S and antithrombin III were normal. Heparin cofactor II (HC II) activity was decreased (44%) with normal HC II antigen (79%) and so she was diagnosed as heparin cofactor II deficiency type II (heparin cofactor II abnormality). Her father manifesting thromboangitis obliterans also had low HC II activity with normal HC II antigen. However, on her genetic analysis, we didn't detect any mutations in the coding region of HC II gene. Until now she has no recurrence of cerebrovascular attacks. On the basis of these results, we suspect that HC II deficiency was a possible risk factor of cerebral infarction in this case because she was so young and had no general risk factors except for HC II. No stroke associated with HC II deficiency type II has been reported up to date. This case is worth considering etiologies of juvenile cerebral infarction.

Long-term follow-up of patients with mild coronary artery disease and endothelial dysfunction

BACKGROUND

Coronary endothelial dysfunction is characterized by vasoconstrictive response to the endothelium-dependent vasodilator acetylcholine. Although endothelial dysfunction is considered an early phase of coronary atherosclerosis, there is a paucity of information regarding the outcome of these patients. Thus, this study was designed to evaluate the outcome of patients with mild coronary artery disease on the basis of their endothelial function.

METHODS AND RESULTS

Follow-up was obtained in 157 patients with mildly diseased coronary arteries who had undergone coronary vascular reactivity evaluation by graded administration of intracoronary acetylcholine, adenosine, and nitroglycerin and intracoronary ultrasound at the time of diagnostic study. Patients were divided on the basis of their response to acetylcholine into 3 groups: group 1 (n=83), patients with normal endothelial function; group 2 (n=32), patients with mild endothelial dysfunction; and group 3 (n=42), patients with severe endothelial dysfunction. Over an average 28-month follow-up (range, 11 to 52 months), none of the patients from group 1 or 2 had cardiac events. However, 6 (14%) with severe endothelial dysfunction had 10 cardiac events (P<0.05 versus groups 1 and 2). Cardiac events included myocardial infarction, percutaneous or surgical coronary revascularization, and/or cardiac death.

CONCLUSIONS

Severe endothelial dysfunction in the absence of obstructive coronary artery disease is associated with increased cardiac events. This study supports the concept that coronary endothelial dysfunction may play a role in the progression of coronary atherosclerosis.

Cholesterol-lowering treatment is associated with improvement in coronary vascular remodeling and endothelial function in patients with normal or mildly diseased coronary arteries

Coronary vascular remodeling and altered endothelial function have been described in the early stages of native atherosclerosis. The purpose of this study was to evaluate the association between cholesterol-lowering therapy and coronary vascular remodeling and endothelial function in patients with normal or mildly diseases coronary arteries. Patients (N=101) with normal or mildly diseased coronary arteries by coronary angiography underwent intravascular ultrasound examination of the left anterior descending coronary artery. Vessel and lumen area, atherosclerotic plaque area, and plaque morphology were evaluated. Vascular reactivity was examined with the use of intracoronary adenosine, acetylcholine, and nitroglycerin. Patients were divided into 3 groups based on the total cholesterol levels: group 1 (n=25), patients with a history of hypercholesterolemia adequately treated (total cholesterol <240 mg/dL); group 2 (n=26), patients with hypercholesterolemia not adequately controlled (total cholesterol >/=240 mg/dL); and group 3 (n=50), patients without hypercholesterolemia. Vessel area and lumen area were significantly greater in groups 1 and 3 than in group 2 (for respective values in groups 1, 2, and 3: vessel area 11.9+/-0.5, 10.6+/-0.4, and 11.8+/-0.4 mm(2), both P<0.05; lumen area 8.3+/-0.4, 6.9+/-0.3, and 8.9+/-0.3 mm(2), both P<0.01). However, plaque areas in groups 1 and 2 were similar. Furthermore, acetylcholine-induced percent increases in coronary blood flow were significantly greater in groups 1 and 3 than in group 2 (for respective values in groups 1, 2, and 3: 70.5+/-20.1%, 22.8+/-13.7%, and 68.6+/-14.8%, both P<0. 05). Cholesterol-lowering treatment is associated with an improvement in coronary lumen area that results not from a decrease in plaque area but from an increase in vessel area, reflecting vascular remodeling. Additionally, this adaptive process may occur in association with an improvement of endothelium-dependent vasodilation of the resistance coronary artery.

[A case of herpes zoster encephalitis with Ramsay-Hunt syndrome, herpes zoster generalisatus and acute pancreatitis]

We describe here a 71-year-old man who had herpes zoster encephalitis. He developed high fever, headache and disturbance of consciousness on 1st, May, 1998. On admission, neurological examination revealed disturbance of consciousness with restlessness and meningeal signs. Brain MRI (T 1 and T 2 weighted images) demonstrated high signal lesions in the left temporal lobe and cerebellar vermis. VSV encephalitis was diagnosed based on CSF pleocytosis, high serum and CSF titers of VZV antibody and EEG abnormality. During hospitalization, Ramsay-Hunt syndrome, herpes zoster generalisatus and acute pancreatitis developed. To our knowledge, the characteristic combination of the clinical signs in this case is very rare. We discussed the pathogenic mechanisms of these conditions, and this case was considered to have VZV encephalitis, and to be associated with right facial nerve palsy and pancreatitis, in spite of the absence of immunological deficiency.

Relationship between the clinical efficacy of pentoxifylline treatment and elevation of serum T helper type 2 cytokine levels in patients with human T-lymphotropic virus type I-associated myelopathy

OBJECT

Previously, we reported the efficacy of pentoxifylline (PTX) treatment in human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM). Here, we clarify the relationship between the clinical efficacy of PTX treatment and elevation of T helper type 2 (Th2) cytokine levels in HAM patients.

PATIENTS AND METHODS

PTX (300 mg) was administered daily by the oral route to 12 HAM patients for 4 weeks. We assessed the relationship between the changes in neurological status (motor disability scores, the degree of spasticity on neurological examination, and the time required to walk 10 m) and the changes in serum and cerebrospinal fluid (CSF) levels of interferon-gamma (IFN-gamma) as a Th1 cytokine and interleukin-4 and -10 (IL-4 and -10) as Th2 cytokines measured by an EASIA (enzyme-amplified sensitivity immunoassay) kit.

RESULTS

PTX treatment induced incremental increases in the levels of IL-4 and IL-10 in both sera and CSF of 6 HAM patients. Clinical improvement was associated with this elevation in IL-4 and IL-10. PTX treatment also induced a decrease in IFN-gamma levels in the sera of 6 HAM patients, but this was not correlated with clinical improvement.

CONCLUSION

These results suggest that the correction of the immunological imbalance in Th1 to Th2 cytokine responses, with upregulation of IL-4 and IL-10, may account for the clinical improvement in HAM patients treated with PTX.

Elevated levels of interleukin-12 and interferon-gamma in patients with human T lymphotropic virus type I-associated myelopathy

The levels of interleukin-12 (IL-12) (p70 heterodimer), total IL-12 (p70 heterodimer plus p40 chains), interferon-gamma (IFN-gamma) as Th1 cytokine, and those of interleukin-4 (IL-4) and interleukin-10 (IL-10) as Th2 cytokines in sera and cerebrospinal fluid (CSF) from 22 patients with human T lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) were compared with those of 22 patients with other neurological diseases (OND), including nine anti-HTLV-I-seropositive carriers. Both serum IL-12 (total and p70 heterodimer) and CSF IFN-gamma, measured by the enzyme-linked immunosorbent assay (ELISA), were significantly elevated in patients with HAM as compared to the patients with OND, including the anti-HTLV-I-seropositive carriers. Serum IFN-gamma also was significantly elevated in the HAM patients as compared to the controls. There was no significant difference in the CSF levels of IL-12 (total and p70 heterodimer) between the HAM patients and controls, whereas, for the Th2 cytokines IL-4 was detected in the CSF of four anti-HTLV-I-seropositive carriers of the 13 control patients but not in any of the patients with HAM. No significant difference was found in the serum levels of IL-4 and IL-10, nor in the CSF levels of IL-10 in the patients with HAM and in the controls. These findings indicate that in patients with HAM, the immunological balance of helper T lymphocytes between Th1 and Th2 is toward Th1 in the periphery and that Th1-mediated immunological status in the central nervous system is involved in the pathogenesis of HAM.

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.

[Beneficial effects of acetazolamide on paroxysmal attacks of girdle sensation in multiple sclerosis]

A 56-year-old woman with a 40-year history of multiple sclerosis (MS) developed paroxysmal attacks of girdle sensation in the Th5-6 dermatomes. The attacks lasted 20-60 minutes and occured up to three times per week. T2-weighted MR imaging of the spinal cord showed high intensity area from Th5 to Th8. Electrocardiography, echocardiography and laboratory findings did not indicate ischemic heart disease; therefore, the paroxysms were attributed to the spinal cord lesions. Attacks were successfully suppressed by acetazolamide 250 mg/day. Although carbamazepine is frequently used to treat paroxysmal attacks in MS, we would like to suggest that acetazolamide may also be beneficial in some patients with paroxysmal symptoms.

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.

[Persistent lateral gaze palsy and abducens nerve palsy due to pontine infarction]

A 76-year-old hypertensive man noticed sudden dizziness and diplopia. On examination, right-sided gaze deviation was present, but the remainder of the neurological examination was normal. Five days later, MRI revealed a small lesion in the left paramedian pontine tegmentum, which was consistent with pontine infarction. The conjugate deviation disappeared about two weeks after the onset, but a left lateral gaze and abducens nerve palsy have persisted at ten months after the infarct. MRI findings are unchanged. The site of infarction is presumed to be located in the caudal portion of paramedian reticular formation and the abducens nerve fascicle. Persistent lateral gaze palsy is rare in pontine infarction, and this case is important in illustrating the anatomical location of paramedian pontine reticular formation.

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.

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.

A case of dyshormonogenetic goiter complicated with growth hormone deficiency

A 17-year-old male patient with dyshormonogenetic goiter complicated with follicular adenoma and growth hormone deficiency is described. He had short stature (-2.3 SD), diffuse goiter and a particularly large nodule in the right lobe of the thyroid gland. The endocrinological studies revealed slight hypothyroidism. He underwent surgical removal of the tumor, diagnosed histopathologically as follicular adenoma, embryonal type; and the diffuse goiter was diagnosed as dyshormonogenetic goiter. It was speculated that long-term hypersecretion of thyroid stimulating hormone (TSH) caused adenoma in the thyroid gland. Although the goiter disappeared after oral thyroxine replacement therapy, his height gain remained poor. Then, he was diagnosed partial growth hormone deficiency, and growth hormone therapy improved his height gain. It has been reported that a high percentage of patients with congenital hypothyroidism have additional anomalies. This is, however, the first reported case of dyshormonogenetic goiter complicated with growth hormone deficiency.

Increase in the delta ST/delta heart rate (HR) index: a new predictor of restenosis after successful percutaneous transluminal coronary angioplasty

With the goal of improving the prediction of restenosis after percutaneous transluminal coronary angioplasty (PTCA), we evaluated the usefulness of the delta ST/delta heart rate (HR) index derived from serial exercise treadmill tests. Exercise treadmill tests were performed by 125 patients with single-vessel coronary artery disease before and several days after PTCA, and just before follow-up angiography 3 to 12 months later. Simple HR-adjusted indexes of ST-segment depression during exercise (delta ST/delta HR index) were derived. We compared the usefulness of the increase in delta ST/delta HR index at follow-up over the value obtained several days after PTCA for prediction of restenosis with that of a positive exercise treadmill test and a positive thallium scintigram at follow-up. At follow-up, 47 of the 125 patients showed restenosis. The delta ST/delta HR index increased in 43 of 47 patients in the restenosis group and in 18 of 78 patients without restenosis (p < 0.0001). Separate analysis of each criterion revealed the following respective values for sensitivity, specificity, and positive and negative predictive values for prediction of restenosis; increased delta ST/delta HR index of follow-up: 91%, 77%, 70%, and 94%; positive exercise treadmill test: 83%, 65%, 59%, and 86%; and positive thallium scintigram: 79%, 78%, 69%, and 86%. The increased delta ST/delta HR index had a significantly (p < 0.05) higher sensitivity than the positive thallium scintigram and a significantly (p < 0.01) higher specificity than the positive exercise treadmill test. An increased delta ST/delta HR index at follow-up identifies subgroups of patients who are at high risk for restenosis after PTCA.

High serum concentration of lipoprotein(a) is a risk factor for restenosis after percutaneous transluminal coronary angioplasty in Japanese patients with single-vessel disease

To determine the relation between the concentration of lipoprotein(a) [Lp(a)] and restenosis after percutaneous transluminal coronary angioplasty (PTCA) in Japan, we studied 80 consecutive patients with single-vessel disease who successfully underwent PTCA. All were evaluated by follow-up angiography a mean of 6.9 months after PTCA and were divided into the restenosis (30 patients) and the non-restenosis (50 patients) groups. The serum Lp(a) concentration of 29 +/- 17 mg/dl in the restenosis group was significantly higher than that of 17 +/- 14 mg/dl in the nonrestenosis group (p < 0.01). Multiple logistic regression analysis for risk factors revealed a significant correlation between restenosis and Lp(a) (p < 0.003). The serum Lp(a) concentration was positively correlated with the coronary artery percent stenosis at the time of follow-up angiography (r = 0.32, p < 0.01). High serum concentration of Lp(a) is therefore a risk factor for restenosis after PTCA in Japan.

Right ventricular stiffness measured by a new method without volume estimation in coronary artery disease

This study was designed to measure the right ventricular (RV) stiffness (delta P/ delta V) with a new method without estimating the RV volume itself. RV stiffness has rarely been measured due to the difficulty in estimating the RV volume. Without measuring RV volume itself, stiffness can be determined by measuring its volume change (delta V). Tricuspid filling flow volume, which is the diastolic RV delta V, is measurable by using Doppler echocardiography. Thus, RV stiffness may possibly be obtained from Doppler echocardiography combined with high-fidelity RV pressure. Subjects consisted of 8 controls, 8 patients with angina pectoris, 8 with anterior, 8 with posterior, and 8 with inferior prior myocardial infarction. Tricuspid annular dimension was measured by 2-dimensional echocardiography and the tricuspid annular area was calculated. Velocity-time integral of the tricuspid filling flow during the late diastole was measured by pulsed Doppler echocardiography. Then, the late diastolic RV delta V was obtained as the product of the tricuspid annular area and the integral. The late diastolic RV pressure rise (delta P) was also measured with a micromanometer catheter. The RV elastic chamber stiffness constant ([delta P/ delta V]/P) was obtained by dividing simple stiffness by the mean RV pressure during late diastole. The RV elastic chamber stiffness constant did not significantly differ among controls, patients with angina pectoris, and those with anterior and posterior myocardial infarction (0.0054 +/- 0.0009 vs 0.0057 +/- 0.0018 vs 0.0064 +/- 0.002 vs 0.0052 +/- 0.0019 ml-1). However, it was significantly increased in patients with inferior myocardial infarction (0.010 +/- 0.004 ml-1, p < 0.01 or 0.05) compared with those in the other 4 groups. These results suggest (1) that RV stiffness can be measured with a new method without RV volume estimation, and (2) that this new method is useful in evaluating RV diastolic pathophysiology in patients with coronary artery disease.

Increased heparin-releasable platelet factor 4 and D dimer in patients one month after the onset of acute myocardial infarction: persistent activation of platelets and the coagulation/fibrinolytic system

To evaluate the activity of platelets and the coagulation/fibrinolytic system 1 month after the onset of acute myocardial infarction, we measured the plasma levels of molecular markers, i.e. beta-thromboglobulin, platelet factor 4, thrombin-antithrombin III complex and D dimer, in 16 patients with acute myocardial infarction and in 11 normal subjects. Blood was drawn through a catheter placed in the pulmonary artery before heparin injection. The heparin-releasable platelet factor 4 was calculated by subtracting the level before the injection of 5000 U of heparin, from the level 5 min after injection. The plasma beta-thromboglobulin, thrombin-antithrombin III complex and the D dimer levels in the acute phase of myocardial infarction were 134.9 +/- 121.2, 11.2 +/- 7.1 and 164.4 +/- 115.3 ng/ml, respectively. These values were significantly higher than those in the normal subjects. The plasma levels of beta-thromboglobulin and thrombin-antithrombin III complex, 1 month after the onset (36.6 +/- 16.4 and 4.6 +/- 2.3 ng/ml, respectively) were not significantly different from those of the normal subjects. In contrast, D dimer and heparin-releasable platelet factor 4 were 216.9 +/- 176.9 and 80.5 +/- 29.3 ng/ml, respectively, and significantly higher than in the normal subjects. These findings suggest a latent but persistent activation of the platelets and the coagulation/fibrinolytic system 1 month after the onset of acute myocardial infarction.

Rapid diagnosis of coronary reperfusion by measurement of myoglobin level every 15 min in acute myocardial infarction

OBJECTIVES

The purpose of this study was to examine whether coronary reperfusion can be diagnosed rapidly and accurately by myoglobin measurements.

BACKGROUND

When intravenous thrombolysis is used for acute myocardial infarction, it is important to determine coronary reperfusion rapidly and noninvasively so that further treatment can be initiated.

METHODS

We determined myoglobin, creatine kinase (CK) and creatine kinase, MB fraction (CK-MB) isoenzyme levels in 63 patients with acute myocardial infarction with total occlusion of the infarct-related artery that was confirmed by coronary angiography. Myoglobin was measured by turbidimetric latex agglutination, which has an assay time of 10 min. We measured myoglobin, CK and CK-MB every 15 min in 45 patients with and 18 patients without reperfusion. The condition of the infarct-related artery was confirmed every 5 to 8 min by coronary angiography.

RESULTS

The rate of increase in myoglobin, CK, and CK-MB at 15, 30, 45 and 60 min after treatment and reperfusion was significantly higher in the reperfused than in the nonreperfused group. In the reperfused group, the rate of increase in myoglobin was significantly higher than the corresponding rate of increase in CK and CK-MB at 15, 30 and 45 min after reperfusion. When reperfusion was evaluated on the basis of a cutoff level (myoglobin > or = 2.0, CK > or = 1.8, CK-MB > or = 1.5), the predictive accuracy of myoglobin (95%) was significantly higher than that of CK (68%) and CK-MB (73%) at 15 min after reperfusion.

CONCLUSIONS

Coronary reperfusion can be rapidly and accurately detected by measurement of the plasma myoglobin every 15 min.

Calcitonin release from medullary thyroid carcinoma by thyrotropin-releasing hormone: comparison with calcium injection

The effects of thyrotropin-releasing hormone on the release of calcitonin were investigated in 15 normal subjects and 12 patients with medullary thyroid carcinoma. The present study also compared the effect of TRH stimulation with calcium infusion test on calcitonin release in patients with medullary thyroid carcinoma. In normal subjects, calcitonin increased from a basal value of 7.5 +/- 2.5 pmol/l to a peak value of 9.4 +/- 3.0 pmol/l (p less than 0.01) after iv injection of synthetic TRH (500 micrograms). Basal calcitonin values in patients with medullary thyroid carcinoma were high (1216 +/- 2230 pmol/l, p less than 0.05), and TRH induced a further increase in calcitonin to 1842 +/- 3149 pmol/l in all the patients (p less than 0.05). They had a peak value of 7891 +/- 13,528 pmol/l after the calcium infusion, which was significantly higher than the basal value of 1463 +/- 2630 pmol/l (p less than 0.05). All medullary thyroid carcinoma patients displayed a marked calcitonin increase after TRH and calcium stimulation. Although the increase in serum calcitonin after TRH injection was lower than that after calcium injection (1.6-fold vs 5.4-fold, p less than 0.05), there was no significant difference in mean peak calcitonin value following TRH and calcium injection in patients with medullary thyroid carcinoma. These results indicated that TRH could stimulate calcitonin release from the thyroid C-cells in both normal subjects and patients with medullary thyroid carcinoma.

Isolation of Yersinia enterocolitica serovar O8 from free-living small rodents in Japan

Yersinia species were isolated from 65 of 223 free-living small mammals trapped in 10 regions on Honshu Island in Japan. Of the 65 strains isolated, 1 was Yersinia enterocolitica serovar O3, 8 were Y. enterocolitica O5, 6 were Y. enterocolitica O8, 3 were Y. enterocolitica O9, and 1 was Yersinia pseudotuberculosis 4b. Of the six Y. enterocolitica O8 strains, five were positive for autoagglutination, Ca2+ dependence, and the 45-MDa virulence plasmid and showed high pathogenicity for mice.

Salt sensitivity and central dopaminergic activity in patients with essential hypertension

The pathophysiological role of the central dopaminergic mechanism in human essential hypertension (EHT) is still unknown, so we investigated a possible relationship between the central dopaminergic activity and salt sensitivity to blood pressure in patients with EHT. We divided 22 inpatients with EHT into salt-sensitive (SS, n = 11) and non-salt-sensitive (NSS, n = 11) groups according to an 8% increase of mean blood pressure (MBP) when dietary salt intake was increased from 2 g/day to 20 g/day for two periods of 7 days each. The change of central dopaminergic activity by salt load was evaluated as the percentage change of plasma prolactin (PRL) response to a small dose (25 micrograms) of thyrotropin-releasing hormone (TRH) administered intravenously. The mean percentage change of PRL response by salt load in the SS group was -9.4 +/- 8.5% (mean +/- SEM), which was remarkably lower than the 26.8 +/- 5.5% in the NSS group (P less than .01). There was a significant negative correlation between the percentage change of PRL response and that of MBP by salt load (r = -0.456, P less than .05). These results suggest that a lack of activation of the central dopaminergic system by salt load may contribute in part to a rise in blood pressure in SS patients with EHT.

Localization of aldosterone-producing adenoma: venous sampling in primary aldosteronism

Adrenal venous sampling of blood was performed for nine patients with aldosterone-producing adenoma (APA). Measurement of adrenal venous aldosterone is useful for localization of APA but difficult, because catheterization of the right adrenal vein is not easy, and the blood is diluted by nonadrenal flow. To solve these problems, levels of aldosterone (A; ng/dl) and cortisol (C; micrograms/dl) were measured in samples from the left adrenal vein (LAV) and the inferior vena cava (IVC), and the LAV A/C and (LAV A/C)/(IVC A/C) ratios were calculated. These ratios were also obtained for 16 patients with essential hypertension. The adenoma could be localized in three of the nine cases by the measurement of aldosterone alone, but the use of a LAV A/C ratio greater than 5 x 10(-3) and a (LAV A/C)/(IVA A/C) ratio less than 1.0 as criteria separated the patients into those with a left APA, right APA, or essential hypertension. Consequently, adrenal venous sampling and the calculation of these ratios enables preoperative localization of APA with more accuracy, especially when the tumor is small or the result of CT and adrenal scintigraphy is not consistent.

A survey for Yersinia pseudotuberculosis in migratory birds in coastal Japan

Yersinia pseudotuberculosis was isolated from three specimens of two species of birds, the black-faced bunting (Emberiza spodocephala) and pied wagtail (Motacilla alba), of 528 specimens of birds examined from coastal regions in Japan. The two isolated strains of Y. pseudotuberculosis were identified as serovar 4b and serovar 3. This is the first isolation of Y. pseudotuberculosis from birds in Japan. Yersinia enterocolitica was isolated from three specimens of the pied wagtail, one specimen of the reed bunting (Emberiza schoeniclus) and one specimen of the rustic bunting (Emberiza rustica). Yersinia frederiksenii was isolated from two specimens of the gray-rumped sandpiper (Heteroscelus brevipes). Yersinia intermedia was isolated from one specimen of the pied wagtail.

[Lateralisation of aldosterone-producing adenoma in primary aldosteronism]

Four lateralizing methods were carried out in 14 patients with primary aldosteronism (PA): ultrasonography, CT scan, adrenal scintiscan and determination of adrenal venous aldosterone levels. In all cases, unilateral aldosterone-producing adenomas were verified by surgery. Of four lateralizing methods, determination of adrenal venous aldosterone, in spite of high diagnostic value, has two big problems: difficulty in selective catheterization of right adrenal vein and dilution of adrenal vein efflux from non-adrenal sources. To solve these problems, cortisol (C, micrograms/dl) levels along with aldosterone (A, ng/dl) were determined in samples from the left adrenal vein (LAV) and the inferior vena cava (IVC) in 8 patients with PA, and the (LAV A/C)/(IVC A/C) ratio was calculated. That ratio was also obtained in 7 patients with other types of hypertension for comparison. Accuracy of lateralisation by ultrasonography, CT scan and adrenal scintiscan was 23%, 64% and 69% respectively, in the first studies. Those rates changed to 23%, 93% and 85% when the second studies were performed. Venous blood was obtained from both adrenal veins in 46% (6/13), while lateralisation of adenoma was also predicted in 46% (6/13) by the measurement of aldosterone concentrations alone. On the other hand, (LAV A/C)/(IVC A/C) ratios were 3.54-6.98 in the cases of left APA, 0.15-0.98 in those of right APA and 1.10-2.86 in cases of other types of hypertension. There was no overlap of ratios among the three groups, resulting in correct prediction of lateralisation in all cases (8/8) of APA.(ABSTRACT TRUNCATED AT 250 WORDS)

[Salt sensitivity and central dopaminergic activity in patients with essential hypertension]

The pathophysiological role of the central dopaminergic mechanism in human essential hypertension (EH) is still unknown. We studied on the relationship between the dopaminergic activity and the salt-sensitivity. Twenty three hospitalized patients with EH were divided into the salt-sensitive group (SS, n = 12) or non salt-sensitive group (NSS, n = 11) by their responses whether they caused more than 8% increase in mean blood pressure (MBP) when the dietary salt was increased from 2g/day to 20g/day for 7 days of each. The change of central dopaminergic activity by the salt load was evaluated by the decrement of plasma prolactin (PRL) response to small dosage (25 micrograms) of thyrotropin releasing hormone. The mean percent change of PRL response by the salt load in the SS group was -6.5 +/- 8.3% (mean +/- SEM), which was significantly lower than 26.8 +/- 5.5% in the NSS group (p less than 0.01). There was a significant negative correlation between the percent changes of PRL response and the percent changes of MBP by the salt load (r = -0.448, p less than 0.05). These results suggested that the rise in blood pressure by salt load in SS patients with EH might be due to a reduced activity of the central dopaminergic mechanism.

The effect of iopanoic acid on thyrotropin secretion in patients with cirrhosis of the liver

Ten patients with liver cirrhosis and six normal subjects were studied to evaluate the effect of iopanoic acid (IA) on thyrotropin secretion. A thyrotropin-releasing-hormone (TRH) test was performed before and 5 days after IA administration (single oral dose of 3 g). After IA administration, a significant increase in TSH response to TRH was observed in normal subjects. In cirrhotics, however, it did not significantly increase after IA administration. The serum T3 and T3/TBG ratio were significantly decreased and the serum T4 and T4/TBG ratio were increased after IA administration in normal subjects and cirrhotics. There was no significant difference in the % decrease in serum T3, % increase in serum T4 or other thyroid hormone parameters including TSH in IA induced TSH responders (R) and non-responders (NR). However, r-T3 before and after IA in R was higher than those in NR. The values for hepatic function tests such as serum albumin, prothrombin time, 45 minutes retention rate of bromsulphalein (BSP 45 min) and the cholinesterase (ChE) level in R were not different from those of NR. These results suggested that in cirrhotics, abnormal regulation of the hypothalamo-pituitary system might exist.

[Two-dimensional contrast echocardiographic assessment of the time course of regional ischemic myocardial function]

The time course of percent fractional area change (%FAC) of the ischemic left ventricular wall as identified by myocardial contrast echocardiography was assessed. Two-dimensional echocardiograms of the left ventricular short axis at the level of the chordae tendineae were recorded in 16 anesthetized open-chest dogs. Myocardial ischemia was produced by occluding the left circumflex coronary artery (LCX) for 30 min, and identified by myocardial contrast echocardiography using aortic root contrast injection. The left ventricular wall in the short-axis view was divided into eight segments. The experiments were completed in nine dogs. The %FAC of the segment which includes the center of the ischemic area was normal before LCX occlusion (35 +/- 6%: mean +/- S.D.), markedly decreased during 30 min of LCX occlusion (-3 +/- 4%) and gradually recovered after coronary reperfusion. However, it was significantly decreased 150 min after reperfusion (8 +/- 9%) (p less than 0.001) compared to that before LCX occlusion. The %FAC of the segment which includes the center of the non-ischemic area was not significantly changed throughout the experiment. In conclusion, 1) the time course of regional ischemic myocardial function could be assessed by the analysis of the %FAC of the ischemic area determined by myocardial contrast echocardiography, 2) the %FAC is significantly decreased 150 min after coronary reperfusion following 30 min occlusion compared to that before coronary occlusion.

Assay of a circulating sodium pump inhibitor in patients with essential hypertension and normotensive subjects

The plasma levels of a sodium pump inhibitor (Na+ PI) were measured by a modified method of Hamlyn et al, using dog kidney Na+, K+-ATPase. When the level of Na+ PI was expressed as the % inhibition of the enzyme and compared with that of a control solution, it was found to be 9.0 +/- 0.7% in 43 untreated patients with essential hypertension. This was significantly higher than 5.0 +/- 0.4% for 56 normotensive subjects (p less than 0.01). Male patients with essential hypertension showed the highest mean value of 10.5 +/- 1.1%, disclosing an apparent sex difference in the patient group (p less than 0.01). Only in female patients was there a significant positive correlation between the inhibitor's level and the mean blood pressure (r = 0.649, p less than 0.01). These results provided additional evidence for increased Na+ PI in the plasma of patients with essential hypertension, which might bear an important role in the pathogenesis of the disease.

Masked thyroid dysfunction among elderly patients with atrial fibrillation

Seventy-five elderly patients with atrial fibrillation (41 males and 34 females with a mean age of 75.6 years) were studied to evaluate the incidence of masked thyroid dysfunction. A thyrotropin (TSH)-releasing-hormone (TRH) test (intravenous injection of 250 micrograms of synthetic TRH) was performed in the patients and 30 age matched controls without atrial fibrillation. In the controls, no abnormal TRH stimulated TSH response was observed. In the patients with atrial fibrillation, no response of TSH to TRH (hyperthyroidism) was found in 5 cases (6.6%), while hyperresponse of TSH to TRH (hypothyroidism) was found in 6 cases (8.0%). Thyroid dysfunction (hyper or hypothyroidism) was more frequently observed in the patients than in the controls (p less than 0.05). Two of 5 hyperthyroid patients had normal thyroid hormone levels. All patients with hyperthyroidism were treated with antithyroid drugs or 131I. Unfortunately, atrial fibrillation persisted in all but 1 case. It is concluded that the TRH test is a useful screening test for detecting those patients with abnormal thyroid function among elderly patients with atrial fibrillation, and that hypothyroidism should be considered as a cause of atrial fibrillation in the elderly.

Clinical evaluation of the captopril screening test for primary aldosteronism

In order to investigate the validity of angiotensin converting enzyme inhibition with captopril as a screening test for primary aldosteronism (PA), 50 mg of captopril were administered orally to 7 patients with PA, 17 with essential hypertension (EH), 5 with renovascular hypertension (RVH), 2 with renoparenchymal hypertension (RH) and 8 normal volunteers. The plasma aldosterone concentration (PAC) was suppressed to less than 15 ng/dl in all of the EH, RVH and RH patients and normal subjects 90 min after administration of captopril, but not suppressed in 6 of 7 patients with PA. In addition, the plasma renin activity (PRA) was increased to greater than 1 ng/ml/h in 10 of 17 patients with EH and in all with RVH, RH and the normal controls, but to less than that in 6 of 7 PA and the remaining EH patients. The PAC to PRA ratio after captopril was greater than 20 in all patients with PA, while it remained below 20 in EH, RVH and RH patients and normal controls. From these results, we conclude that the PAC to PRA ratio in the captopril administration test is a simple and useful tool to detect PA in hypertensive patients. In addition, the test has a great advantage in that it can be safely applied to outpatients with relatively severe hypertension.

Vasodilatory and diuretic actions of alpha-human atrial natriuretic polypeptide (alpha-hANP)

Vascular and diuretic actions of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) were studied using anesthetized dogs and isolated canine arterial strip preparations. alpha-hANP, when given intra-arterially or intravenously, dilated the renal artery more selectively than the vertebral, femoral, common carotid and coronary arteries. alpha-hANP selectively relaxed the high K+-contracted renal artery strip as compared with the basilar, coronary and femoral arterial strips. Intravenous alpha-hANP also increased urine volume and urinary excretion of electrolytes at doses, at which it increased renal blood flow and lowered systemic blood pressure without changing heart rate. It is concluded that alpha-hANP has a vasodilatory property relatively specific for the renal artery, and that it possesses diuretic, natriuretic, kaliuretic, magnesiuretic, calciuretic and chloruretic activities concomitantly with a definite hypotensive activity.

Thyroid antibodies in healthy blood donors

The frequency of thyroid antibodies was investigated in 1314 healthy blood donors. Twenty-three of 870 males (2.6%) were positive for thyroglobulin antibody (TA), 34 (3.9%) for thyroid microsomal antibody (MA) and 19 (2.2%) for both TA and MA. Thirty-four of 484 females (6.2%) were positive for TA, 46 (9.5%) for MA and 29 (6.0%) for both TA and MA. Eighty-six of 1314 blood donors were positive for TA and/or MA. There was no difference in liver function tests between AAT and controls. In females, the incidence of thyroid antibodies tended to increase with age. However, the subjects aged under 19 showed another peak of incidence of thyroid antibodies. The values of total T4, T3 and free T4 were not different between 86 subjects with positive thyroid antibodies (asymptomatic autoimmune thyroiditis, AAT) and 86 sex- and age-matched controls without thyroid antibodies, whereas serum TSH of AAT was significantly higher than that of controls. Nine of 86 (10.5%) subjects with AAT had apparently increased basal TSH level.