MR Imaging of the Liver before and after Transcatheter Hepatic Chemo-Embolization for Hepatocellular Carcinoma

Transcatheter chemo-embolization (TCE) in hepatocellular carcinoma (HCC) was performed in 38 patients. The patients were examined by MR imaging before TCE as well as one week and 4 to 5 weeks after TCE. The tumor signal intensity in T2 weighted images increased in 13 cases and decreased in 19 cases after TCE. Increased intensity seemed to reflect intra-tumoral hemorrhage or liquefaction accompanying tumor necrosis. Decreased intensity seemed to reflect coagulation necrosis. In 9 of 18 cases followed over a 2-month period the signal intensity had decreased in both T1 and T2 weighted images. In these patients the tumor showed no recurrence at angiography and the decreased signal seemed to reflect the completion of coagulation necrosis. A hyper- and/or hypointense rim around the tumor appeared in 22 cases. These changes were thought to be perifocal edema or granulation tissue around the tumor. MR imaging was useful in evaluating the necrotic process of the tumor after TCE.

Anti-MuSK autoantibodies block binding of collagen Q to MuSK

OBJECTIVE

Muscle-specific receptor tyrosine kinase (MuSK) antibody-positive myasthenia gravis (MG) accounts for 5%-15% of autoimmune MG. MuSK mediates the agrin-signaling pathway and also anchors the collagenic tail subunit (ColQ) of acetylcholinesterase (AChE). The exact molecular target of MuSK-immunoglobulin G (IgG), however, remains elusive. As acetylcholine receptor (AChR) deficiency is typically mild and as cholinesterase inhibitors are generally ineffective, we asked if MuSK-IgG interferes with binding of ColQ to MuSK.

METHODS

We used 3 assays: in vitro overlay of the human ColQ-tailed AChE to muscle sections of Colq-/- mice; in vitro plate-binding assay to quantitate binding of MuSK to ColQ and to LRP4; and passive transfer of MuSK-IgG to mice.

RESULTS

The in vitro overlay assay revealed that MuSK-IgG blocks binding of ColQ to the neuromuscular junction. The in vitro plate-binding assay showed that MuSK-IgG exerts a dose-dependent block of MuSK binding to ColQ by but not to LRP4. Passive transfer of MuSK-IgG to mice reduced the size and density of ColQ to ∼10% of controls and had a lesser effect on the size and density of AChR and MuSK.

CONCLUSIONS

As lack of ColQ compromises agrin-mediated AChR clustering in Colq-/- mice, a similar mechanism may lead to AChR deficiency in MuSK-MG patients. Our experiments also predict partial AChE deficiency in MuSK-MG patients, but AChE is not reduced in biopsied NMJs. In humans, binding of ColQ to MuSK may be dispensable for clustering ColQ, but is required for facilitating AChR clustering. Further studies will be required to elucidate the basis of this paradox.

Progression and prognosis in pure autonomic failure (PAF): comparison with multiple system atrophy

OBJECTIVE

To clarify the progression of autonomic symptoms and functional deterioration in pure autonomic failure (PAF), particularly in comparison with multiple system atrophy (MSA).

METHODS

The investigation involved eight patients with PAF (M/F = 7/1; mean age at onset, 57 years) and 22 with probable MSA matched for age at onset (M/F = 14/8; onset 56 years). Subjects were followed up for neurological symptoms, activities of daily living, and autonomic function for more than seven years. Autonomic functional tests were carried out.

RESULTS

In PAF, fainting or sudomotor dysfunction occurred first, followed by constipation and syncope. Urinary dysfunction developed late, and respiratory dysfunction was not evident. This clinical course contrasted sharply with that in MSA, where early urinary dysfunction usually proceeded to sudomotor dysfunction or orthostatic hypotension (p = 0.004), followed by respiratory dysfunction (p = 0.0004). Results of pharmacological tests also distinguished PAF from MSA. Progression and prognosis in patients with PAF did not worsen, unlike the steady progressive autonomic dysfunction in MSA (p < 0.0001, p < 0.0001, p = 0.0009, and p = 0.003, for progression to modified Rankin scale grade III, IV, V, and death, respectively).

CONCLUSIONS

The time course and pattern of progression of autonomic failure differed significantly between PAF and MSA. Patients with PAF had slower functional deterioration and a better prognosis.

Inhalation of calcium channel blocking agents protects against methacholine-induced bronchoconstriction

The calcium channel blockers, diltiazem and verapamil, and the beta agonist orciprenaline sulfate all demonstrated significant protection against methacholine-induced bronchoconstriction in 11 stable asthmatics (5 males and 6 females). Ten and 20 mg of inhaled diltiazem, 5 mg of verapamil or 30 mg of orciprenaline administered 15 min before stepwise increasing doses of methacholine hydrochloride produced significant reduction in respiratory resistance (Rrs), minimum dose of methacholine hydrochloride required for Rrs increase (Dmin) and bronchial reactivity measured with an Astograph. The mechanism of action of the calcium channel blockers is presumably at the level of the smooth muscle cells themselves. The combination of positive influence and lack of any adverse effect on blood pressure or heart rate with any of the agents tested indicates that their clinical application for alleviation of acute asthma can be recommended.

Primary lateral sclerosis presenting parkinsonian symptoms without nigrostriatal involvement

We encountered three patients with primary lateral sclerosis (PLS) showing bradykinesia, frozen gait, and severe postural instability, as well as slowly progressive spinobulbar spasticity. Cranial magnetic resonance (MR) imaging showed precentral gyrus atrophy. Central motor conduction was markedly prolonged or failed to evoke a response. Positron emission tomography (PET) showed significant reduction of [18F]fluoro-2-deoxy-D-glucose uptake in the area of the precentral gyrus extending to the prefrontal, medial frontal, and cingulate areas. No abnormalities were seen in the nigrostriatal system with PET using [18F]fluorodopa or [11C]raclopride or with proton MR spectroscopy. Thus, widespread prefrontal, medial, and cingulate frontal lobe involvement can be associated with the parkinsonian symptoms in PLS.

Relationship between plasma levels of cardiac natriuretic peptides and soluble Fas: plasma soluble Fas as a prognostic predictor in patients with congestive heart failure

BACKGROUND

Cardiac natriuretic peptides may induce apoptosis in myocytes; however, the relationship between plasma levels of cardiac natriuretic peptides and those of soluble Fas (sFas) and tumor necrosis factor (TNF)-alpha remains unknown in patients with congestive heart failure (CHF).

METHODS AND RESULTS

We measured plasma levels of sFas and TNF-alpha and those of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), norepinephrine, and endothelin 1 in 96 patients with CHF (ejection fraction < 45%). The patients were monitored for 3 years. Plasma levels of sFas and TNF-alpha increased with the severity of CHF. There was no significant correlation between sFas plasma levels and those of ANP and BNP. Cox proportional hazard analysis showed that high levels of sFas (P = .009) and BNP (P < .0001) and a low ejection fraction (P = .019) were independent significant prognostic predictors.

CONCLUSIONS

There is no significant correlation between cardiac natriuretic peptide and sFas levels in plasma. Plasma sFas is a useful prognostic marker independent of neurohumoral factors, suggesting that immune activation and/or apoptosis play a significant role in the pathogenesis of CHF.

Relationship between plasma level of cardiotrophin-1 and left ventricular mass index in patients with dilated cardiomyopathy

OBJECTIVES

The study evaluated the relationship between plasma cardiotrophin-1 (CT-1) concentration and left ventricular (LV) mass in dilated cardiomyopathy (DCM) patients with congestive heart failure (CHF).

BACKGROUND

Cardiotrophin-1 is a newly identified member of the interleukin-6 (IL-6) family of cytokines and one of the endogenous ligands for gp130 signaling pathways in the heart, and it has potent hypertrophic and survival effects on cardiac myocytes. However, the clinical significance of CT-1 is poorly understood.

METHODS

We measured the plasma CT-1 level in 51 consecutive patients with DCM. Patients were classified into two groups: small LV mass index group and large LV mass index group, based on the median level of LV mass index.

RESULTS

The plasma CT-1 level was increased in DCM patients with the severity of CHF and was significantly higher in the large LV mass group than in the small LV mass group, despite the absence of a difference in LV ejection fraction between the two groups. In addition, there was a significant positive correlation between the plasma CT-1 level and the LV mass index (r = 0.627, p < 0.0001). According to stepwise multivariate analyses among hemodynamic and neurohumoral factors, a high plasma CT-1 level showed an independent and significant positive relationship with a large LV mass index in patients with DCM.

CONCLUSIONS

These results indicate that the plasma CT-1 level is increased in patients with DCM and is significantly correlated with the LV mass index, suggesting that CT-1 plays an important role in structural LV remodeling in patients with DCM.

Relationship between transcardiac extraction of aldosterone and left ventricular remodeling in patients with first acute myocardial infarction: extracting aldosterone through the heart promotes ventricular remodeling after acute myocardial infarction

OBJECTIVES

The purpose of this study was to evaluate whether plasma aldosterone (ALD) is extracted or produced through the heart in patients with acute myocardial infarction (AMI) and to determine the relationship between transcardiac extraction of plasma ALD and left ventricular (LV) remodeling.

BACKGROUND

Although we demonstrated that circulating ALD was extracted through the failing heart and that transcardiac extraction of ALD correlated with LV end-diastolic volume index (LVEDVI) in patients with congestive heart failure, the existence and increase of ALD synthase in the hearts of infarct rats were reported, suggesting cardiac production of ALD in patients with AMI.

METHODS

We measured plasma ALD in the aortic root (Ao) and coronary sinus (CS) in 57 consecutive patients who received successful revascularization and enalapril, with first AMI at acute phase and after one month. We also measured plasma procollagen type III aminoterminal peptide (PIIINP) in the CS.

RESULTS

Plasma ALD was significantly lower in the CS than it was in the Ao at the acute phase (84.7 +/- 6.3 pg/ml vs. 105.5 +/- 8.0 pg/ml, p < 0.0001). Significant positive correlations exist between the transcardiac gradient of ALD at the acute phase and the LVEDVI at one month. Moreover, the transcardiac gradient of plasma ALD at the acute phase has a significant correlation with plasma PIIINP, a biochemical marker of fibrosis, after one month. Stepwise multivariate analysis showed that transcardiac extraction of plasma ALD at the acute phase had an independent and significant positive relationship with a large LVEDVI after one month.

CONCLUSIONS

These results indicate that plasma ALD is extracted through the heart in patients with AMI at the acute phase and that the extracted ALD plays an important role in modulating post-infarct LV remodeling.

Cloning and sequencing of two genes encoding chitinases A and B from Bacillus cereus CH

Two genes encoding chitinases A and B (chiA and chiB) from Bacillus cereus CH were cloned into Escherichia coli XL1-Blue MRF', by using pBluescript II SK+, and their nucleotide sequences were determined. Open reading frames of the chiA and chiB genes encoded distinct polypeptide chains consisting of 360 and 674 amino acid residues, respectively, with calculated molecular sizes of 39,470 and 74,261 Da, respectively. Comparison of the deduced amino acid sequences with those of other bacterial chitinases revealed that chitinase A consisted of a catalytic domain, while chitinase B consisted of three functional domains, a catalytic domain, a fibronectin type III-like domain, and a cellulose-binding domain. The primary structures of these two proteins were not similar to each other.

Relationship between tumor necrosis factor-alpha production and oxidative stress in the failing hearts of patients with dilated cardiomyopathy

OBJECTIVES

This study evaluated oxidative stress in the failing ventricle in patients with dilated cardiomyopathy (DCM).

BACKGROUND

Oxidative stress appears to increase in the failing myocardium and may contribute to ventricular dysfunction in patients with DCM. Tumor necrosis factor-alpha (TNF-alpha), which is expressed in the failing heart, may stimulate oxidative stress.

METHODS

We measured plasma oxidized low density lipoprotein (oxLDL) by sandwich enzyme-linked immunosorbent assay using specific antibodies against oxLDL in the aortic root (AO) and the coronary sinus (CS) in control subjects (n = 8) and in 22 patients with DCM and mild congestive heart failure. We also measured the plasma levels of TNF-alpha and angiotensin II.

RESULTS

There was no difference in oxLDL between the AO and CS in control subjects. In contrast, plasma oxLDL was significantly higher in the CS than the AO in patients with DCM, suggesting that the transcardiac gradient ofoxLDL reflects oxidative stress in the failing heart in these patients. Plasma TNF-alpha levels were significantly higher in the CS than the AO with a significant positive correlation of the transcardiac gradient of TNF-alpha and the transcardiac gradient of oxLDL. Moreover, a significant negative correlation existed between the transcardiac gradient of oxLDL and left ventricular ejection fraction. The transcardiac gradient of plasma oxLDL was significantly lower in 6 patients who received carvedilol than in 16 patients who did not receive carvedilol.

CONCLUSIONS

These findings indicate that the transcardiac gradient of oxLDL may be a marker of oxidative stress in the heart and that left ventricular dysfunction may be partly due to the oxidative stress in patients with DCM. In addition, TNF-alpha may stimulate oxidative stress in the failing heart in patients with DCM.

Intravenous atrial natriuretic peptide prevents left ventricular remodeling in patients with first anterior acute myocardial infarction

OBJECTIVES

The study evaluates the effect of atrial natriuretic peptide (ANP) compared with nitroglycerin (GTN) on left ventricular (LV) remodeling after first anterior acute myocardial infarction (AMI).

BACKGROUND

Compared with GTN, ANP suppresses the renin-angiotensin-aldosterone system and endothelin-1 (ET-1), which stimulate LV remodeling.

METHODS

Sixty patients with a first anterior AMI were randomly divided into the ANP (n = 30) or GTN (n = 30) groups after direct percutaneous transluminal coronary angioplasty. We evaluated LV ejection fraction (LVEF), end-diastolic volume index (LVEDVI) and end-systolic volume index (LVESVI) at the acute phase and after one month. We also measured neurohumoral factors during study drug infusion.

RESULTS

There was no difference in the baseline characteristics or LVEF (46.9+/-1.0 vs. 46.8+/-1.3%) between the two groups. Although there was no difference in hemodynamics during the infusion periods, the LVEF was significantly improved after one month compared with the baseline value in both groups, but it was improved more in the ANP group than in the GTN group (54.6+/-1.1%, 50.8+/-1.3%, p < 0.05). Left ventricular enlargement was prevented in the ANP group (LVEDVI, 85.8+/-3.1 ml/m2 to 87.3+/-2.7 ml/m2; p = ns, LVESVI, 45.6+/-1.8 ml/m2 to 41.0+/-2.1 ml/m2, p < 0.05) but not in the GTN group (LVEDVI, 86.2+/-4.1 to 100.2+/-3.7, p < 0.01; LVESVI, 46.3+/-2.8 ml/m2 to 51.1+/-3.0 ml/m2, p = ns). During the infusion, ANP suppressed plasma levels of aldosterone, angiotensin II and ET-1 compared with GTN.

CONCLUSIONS

These findings indicate that in patients with a first anterior AMI, an ANP infusion can prevent LV remodeling better than can GTN, and effectively suppresses aldosterone, angiotensin II and ET-1.

Effect of spironolactone on plasma brain natriuretic peptide and left ventricular remodeling in patients with congestive heart failure

OBJECTIVES

We sought to evaluate the effects of spironolactone on neurohumoral factors and left ventricular remodeling in patients with congestive heart failure (CHF).

BACKGROUND

Aldosterone (ALD) promotes collagen synthesis and structural remodeling of the heart. Spironolactone, an ALD receptor antagonist, is reported to reduce mortality in patients with CHF, but its influence on left ventricular remodeling has not been clarified.

METHODS

Thirty-seven patients with mild-to-moderate nonischemic CHF were randomly divided into two groups that received treatment with spironolactone (n = 20) or placebo (n = 17). We measured left ventricular volume and mass before treatment and after four months of treatment. We also measured the plasma levels of neurohumoral factors, such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), as well as plasma procollagen type III aminoterminal peptide (PIIINP), a marker of myocardial fibrosis.

RESULTS

Left ventricular volume and mass were significantly decreased and ejection fraction was significantly increased in the spironolactone group, while there were no changes in the placebo group. Plasma levels of ANP, BNP and PIIINP were significantly decreased after spironolactone treatment, but were unchanged in the placebo group. There was a significant positive correlation between the changes of PIIINP and changes of the left ventricular volume index (r = 0.45, p = 0.045) as well as the left ventricular mass index (r = 0.65, p = 0.0019) with spironolactone treatment.

CONCLUSIONS

These findings indicate that four months of treatment with spironolactone improved the left ventricular volume and mass, as well as decreased plasma level of BNP, a biochemical marker of prognosis and/or ventricular hypertrophy, suggesting that endogenous aldosterone has an important role in the process of left ventricular remodeling in nonischemic patients with CHF.

Therapeutic use of dopamine and beta-blockers modulates plasma interleukin-6 levels in patients with congestive heart failure

We previously reported that the spillover of interleukin-6 (IL-6) into the peripheral circulation increases with the severity of congestive heart failure (CHF), and that the increase is mainly associated with activation of the endogenous sympathetic nervous system. However, the role of the sympathetic nervous system in the increase of IL-6 in CHF patients is not yet fully understood. To address this question, we measured plasma IL-6 levels before and after therapeutic administration of dopamine and betablockers in patients with CHF. After more than 24 h (mean, 34 h) of treatment with a low dose of intravenous dopamine (mean, 2.4 microg/kg/min) in 1 patients with dilated cardiomyopathy and deterioration of CHF, the plasma IL-6 level was increased significantly (30.8 vs. 16.6 pg/ml; p = 0.003) despite the improved hemodynamics. After 377 days of beta-blocker therapy in 24 patients with dilated cardiomyopathy, the plasma IL-6 level was decreased significantly (2.04 vs. 3.11 pg/ml; p = 0.01) along with the improvement of symptoms, left ventricular ejection fraction, and neurohumoral factors. Dopamine increases and beta-blockers decrease the plasma IL-6 level in patients with CHF, suggesting that drugs modulating the sympathetic nervous system may alter IL-6 in these patients.

High levels of plasma brain natriuretic peptide and interleukin-6 after optimized treatment for heart failure are independent risk factors for morbidity and mortality in patients with congestive heart failure

OBJECTIVES

The aim of this study was to evaluate whether repetitive measurements of plasma levels of neurohumoral factors and cytokines before and after additional treatment are useful for predicting mortality in patients with congestive heart failure (CHF).

BACKGROUND

Neurohumoral and immune activation play an important role in the pathophysiology of CHF. However, the effects of serial changes in these factors on the prognostic value remain unknown.

METHODS

We measured plasma levels of neurohumoral factors and cytokines and left ventricular ejection fraction (LVEF) before and three months after optimized treatment for CHF in 102 consecutive patients with severe CHF (New York Heart Association class III to IV) on admission to our hospital. Physicians who were blind to the plasma neurohumoral factors until study completion treated patients using standard drugs. Patients were monitored for a mean follow-up period of 807 days.

RESULTS

Plasma levels of neurohumoral factors, cytokines and LVEF were significantly improved three months after optimized treatment. Cardiac death occurred in 26 patients. Among 19 variables including LVEF, only a high level of brain natriuretic peptide (BNP) and interleukin-6 (IL-6) at three months after optimized treatment showed significant independent relationships by Cox proportional hazard analysis with a high mortality for patients with CHF.

CONCLUSIONS

These findings indicate that high plasma BNP and IL-6 levels three months after optimized treatment are independent risk factors for mortality in patients with CHF, suggesting that sustained high plasma levels of BNP and IL-6 after additional standard treatment were independent risk factors for mortality in patients with CHF despite improvements in LVEF and symptoms.

Plasma cardiac natriuretic peptides as biochemical markers of recurrence of atrial fibrillation in patients with mild congestive heart failure

To determine changes in plasma brain natriuretic peptide (BNP) after direct current cardioversion (DC) and to evaluate the relationship between plasma atrial natriuretic peptide (ANP) and BNP and the recurrence of atrial fibrillation (AF) after DC in patients with mild congestive heart failure (CHF), plasma ANP and BNP were measured before and after DC in 71 patients with mild CHF and then followed. In 65 patients with successful DC, both ANP and BNP decreased 15 min after DC. Cox stepwise multivariate analysis among 14 variables such as age, history of AF, echocardiographic parameters, medication and ANP and BNP revealed that only low ANP (p=0.005) and high BNP before DC (p=0.0002) were independent predictors of recurrent AF. A ratio of ANP to BNP less than 0.44 was a significant risk factor for AF recurrence by Kaplan-Meier analysis (p=0.02). BNP began to decrease immediately after successful DC. High BNP and relatively low ANP compared with BNP were independent risk factors of AF recurrence in patients with mild CHF.

Spironolactone inhibits the transcardiac extraction of aldosterone in patients with congestive heart failure

OBJECTIVES

The study evaluated the transcardiac extraction or spillover of aldosterone (ALDO) in normal subjects and in patients with congestive heart failure (CHF).

BACKGROUND

Aldosterone promotes collagen synthesis and structural remodeling of target organs such as the heart. Spironolactone, an ALDO receptor antagonist, has recently been reported to reduce the mortality of patients with CHF; however, the effects of spironolactone on the transcardiac gradient of ALDO have not been clarified.

METHODS

We measured plasma ALDO in the aortic root (AO) and coronary sinus (CS) in normal subjects and 113 consecutive CHF patients and also measured plasma procollagen type III aminoterminal peptide (PIIINP) in CS, a biochemical marker of myocardial fibrosis.

RESULTS

Plasma ALDO was significantly lower in the CS than in the AO in normal subjects (n = 15; 61.2 +/- 9.3 vs. 83.1 +/- 11.8 pg/ml, p < 0.0001). In 96 CHF patients who did not receive spironolactone, plasma ALDO was significantly lower in the CS than in the AO (59.3 +/- 3.9 vs. 73.8 +/- 4.9 pg/ml, p < 0.0001). In contrast to the difference in these 96 patients, there was no significant difference in ALDO between the AO and CS in 17 patients who received spironolactone (127.4 +/- 20 vs. 124.0 +/- 19 pg/ml, p = 0.50). Stepwise multivariate analyses showed that spironolactone therapy had an independent and significant negative relationship with the transcardiac gradient of plasma ALDO in patients with CHF. In addition, significant positive correlations were seen between the transcardiac gradient of plasma ALDO and PIIINP (r = 0.565, p < 0.0001) and the left ventricular end-diastolic volume index (r = 0.484, p < 0.0001).

CONCLUSIONS

These results indicate that plasma ALDO is extracted through the heart in normal subjects and in CHF patients who do not receive spironolactone and that spironolactone inhibits the transcardiac extraction of ALDO in CHF patients, suggesting that spironolactone blocks the effects of ALDO on the failing heart in patients with CHF.

Transcardiac extraction of circulating endothelin-1 across the failing heart

To determine the transcardiac gradient of plasma endothelin-1 (ET-1) in patients with congestive heart failure (CHF), we measured plasma levels of ET-1 in both the aortic root and the coronary sinus in 14 normal subjects and 79 consecutive patients with CHF. In normal subjects, plasma ET-1 was significantly higher in the coronary sinus than in the aortic root; these findings were also shown in patients with mild CHF, suggesting that there was ET-1 spillover across the heart. In contrast, plasma ET-1 was significantly lower in the coronary sinus than in the aortic root in patients with severe CHF, suggesting there was ET-1 extraction across the heart in patients with severe CHF. The transcardiac gradient of plasma ET-1 was correlated with the left ventricular end-diastolic volume index (r = 0.501, p <0.0001) and plasma level of procollagen type III amino terminal peptide in the coronary sinus (r = 0.54, p = 0.0008), a marker of myocardial fibrosis. Stepwise multivariate analysis showed that the transcardiac gradient of plasma ET-1 was an independent and significant relation with the left ventricular end-diastolic volume index in patients with CHF (r = 0.665, p <0.0001). These findings suggest that elevated circulating ET-1 is extracted across the failing heart with a significant correlation between the transcardiac gradient of plasma ET-1 and the left ventricular end-diastolic volume index, suggesting that ET receptors are upregulated in the failing ventricle and that the elevated circulating ET-1 might stimulate the process of left ventricular remodeling in patients with severe CHF.

Insufficient secretion of atrial natriuretic peptide at acute phase of myocardial infarction

To investigate the secretion of the plasma levels of atrial natriuretic peptide (ANP) in patients with acute myocardial infarction (AMI), we evaluated the relationship between plasma levels of ANP and pulmonary capillary wedge pressure (PCWP) in 45 consecutive patients during the acute phase of AMI ( approximately 12 h after the attack) (group 1) and compared data with those obtained after 1 mo (group 2). In both groups 1 and 2, plasma ANP levels significantly correlated with PCWP. The slope of the linear regression line between the PCWP and ANP in group 1 was significantly lower, by about one-third, than that in group 2. In addition, we examined changes in ANP levels and left ventricular end-diastolic pressure (LVEDP) over 180 min after AMI induced by injection of microspheres into the left coronary arteries of three dogs. The LVEDP and ANP levels 30 min after AMI were significantly higher than those before; however, despite the persistent high LVEDP during the 180 min after AMI, ANP levels decreased gradually and significantly to 63% of the peak level at 150 min. These findings suggest that the secretion of ANP during the acute phase of myocardial infarction may be insufficient relative to the chronic phase.

[Plasma cardiac natriuretic peptide as a biological marker of recurrence of atrial fibrillation in elderly people]

We designed this study to evaluate the relationship between plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels and recurrence of atrial fibrillation (AF) after direct current cardioversion (DC) and the differences with aging. Fifty patients with mild congestive heart failure (CHF) undergoing elective DC of AF were included in this study (New York Heart Association (NYHA) functional class II: n = 42, III = 8). Patients who failed to show restoration of sinus rhythm or those with mitral valve stenosis were excluded. Before successful DC, we measured plasma levels of ANP and BNP and evaluated left atrial dimension (LAD), left ventricular end-diastolic dimension (LVDd), and left ventricular ejection fraction (EF) by echocardiography. Twenty-one patients had recurrence of AF within 2 months after DC (average 9.05 days). We followed up the other 29 patients for 580.5 days. By Cox stepwise multivariate analysis, history of AF (p = 0.007), low plasma levels of ANP (p = 0.003), and high plasma levels of BNP (p = 0.0003) were found to be independent predictors of recurrent AF. High plasma BNP levels indicating ventricular dysfunction and low plasma ANP levels may be due to atrial histological change such as fibrosis. In these patients, plasma ratios of ANP and BNP (ANP/BNP) less than 0.43 were predictive factors for AF recurrence (sensitivity 70%, specificity 62%), especially in patients who were older than 70 years (sensitivity 100%, specificity 80%). Relatively low plasma ANP level compared to BNP is an independent risk factor of AF recurrence in patients with CHF, especially in elderly patients, suggesting that plasma cardiac natriuretic peptides are important biochemical markers of AF recurrence in elderly patients with CHF.

Characterization of chitinases excreted by Bacillus cereus CH

Bacillus cereus CH was shown to excrete chitinases into the culture supernatant when cultivated in a medium containing 0.2% colloidal chitin, whereas the removal of colloidal chitin resulted in a low activity. After concentration of the culture supernatant by precipitation with ammonium sulfate, the induced chitinases were purified by sequential chromatography. Four different chitinases, A, B1, B2, and B3 with molecular masses of 35, 47, 58, and 64 kDa, respectively, were separated. All chitinases showed similarities in their kinetic parameters when observed with colloidal chitin, including an optimal pH of 5.0-7.5, and an optimal temperature between 50-60 degrees C. Chitinase A hydrolyzed glycol chitin and p-nitrophenyl-di-N-acetyl-beta-chitobioside at similar rates to that of colloidal chitin, whereas group B chitinases hydrolyzed both substrates in much lower rates. From analyses of the reaction products, it is most likely that chitinase A and all group B chitinases hydrolyze the substrates tested in an endo-fashion. However, group B chitinases were distinct from chitinase A in possessing high transglycosylation activity. From amino terminal sequencing, chitinases B1, B2, and B3 were shown to have almost identical sequences, which differed from that of chitinase A. The similarities in the reaction modes and amino terminal sequences among chitinases B1, B2, and B3 suggest that these chitinases may be derived from a presumptive precursor protein through C-terminal processing.

Angiotensin II type 1 receptor antagonist decreases plasma levels of tumor necrosis factor alpha, interleukin-6 and soluble adhesion molecules in patients with chronic heart failure

OBJECTIVES

To evaluate the effects of an angiotensin (Ang II) type 1 receptor antagonist on immune markers in patients with congestive heart failure (CHF).

BACKGROUND

Ang II stimulates production of immune factors via the Ang II type 1 receptor in vitro, and the long-term effects of Ang II type 1 receptor antagonists on plasma markers of immune activation are unknown in patients with CHF.

METHODS

Twenty-three patients with mild to moderate CHF with left ventricular dysfunction were randomly divided into two groups: treatment with Ang II type 1 receptor (candesartan cilexetil) (n = 14) or placebo (n = 9). We measured plasma levels of immune factors such as tumor necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1). We also measured plasma levels of the neurohumoral factors such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) and cyclic guanosine monophosphate (cGMP), a biological marker of ANP and BNP.

RESULTS

Plasma levels of TNFalpha, IL-6, sICAM-1 and sVCAM-1 were increased in the 23 CHF patients compared with normal subjects and significantly decreased after 14 weeks of candesartan cilexetil treatment, but did not change in the placebo group. Plasma levels of BNP, which is a marker of ventricular injury, significantly decreased, and the molar ratio of plasma cGMP to cardiac natriuretic peptides (ANP + BNP) was significantly increased after candesartan cilexetil treatment, but did not change in the placebo group.

CONCLUSIONS

These findings suggest that 14 weeks of treatment with an Ang II type 1 receptor antagonist (candesartan cilexetil) decreased plasma levels of the immune markers such as TNFalpha, IL-6, sICAM-1 and sVCAM-1 and that it improved the biological compensatory action of endogenous cardiac natriuretic peptides in patients with mild to moderate CHF.

Plasma brain natriuretic peptide level as a biochemical marker of morbidity and mortality in patients with asymptomatic or minimally symptomatic left ventricular dysfunction. Comparison with plasma angiotensin II and endothelin-1

AIMS

To evaluate the level of plasma brain natriuretic peptide as a predictor of morbidity and mortality in patients with asymptomatic or minimally symptomatic left ventricular dysfunction.

METHODS

We measured plasma levels of atrial natriuretic peptide, brain natriuretic peptide, norepinephrine, angiotensin II, and endothelin-1 and monitored haemodynamic parameters in 290 consecutive patients with asymptomatic or minimally and newly symptomatic left ventricular dysfunction (functional classes I-II, mean left ventricular ejection fraction=37%). All patients were followed up for a median period of 812 days. The Cox proportional hazards model was used to assess the association of variables with mortality and morbidity.

RESULTS

At the end of the follow-up, 24 patients had suffered cardiac death and 25 had been hospitalized for worsening heart failure during the follow-up period. Among 21 variables such as clinical characteristics, treatment, haemodynamics, and neurohumoral factors, high levels of plasma brain natriuretic peptide (P<0.0001), norepinephrine (P=0.042), left ventricular end-diastolic volume index (P=0.0035), and left ventricular end-diastolic pressure (P=0.033) were shown to be independent predictors of mortality and morbidity by stepwise multivariate analysis. Moreover, only a high level of plasma brain natriuretic peptide (P<0.0001) was shown to be an independent predictor of mortality in these patients.

CONCLUSIONS

These results indicate that a high plasma brain natriuretic peptide level provides information about mortality and morbidity in patients with asymptomatic or minimally symptomatic left ventricular dysfunction.

[Cerebral ischemia in patients with orthostatic syncope--the significance of orthostatic hypotension and large vessel disease in the cervical and intracranial region]

We performed 90 degrees head-up tilting test for 10 minutes in 100 patients (66 men and 34 women) aged 50 years or more suffering from transient orthostatic syncope and measured their systolic blood pressure. Orthostatic hypotension (OH) was found in 51 patients, predominantly in men (38 cases). OH was complicated by large vessel disease (LV) as shown by MR angiography or carotid artery ultrasonography in 19 cases (37.3%). Progressive cerebral ischemia was found more frequently in patients with both OH and LV than in those with OH alone. Within the patients with OH alone, the drop in orthostatic blood pressure was greater in cases where progressive cerebral ischemia was present. In patients with both OH and LV, the minimum orthostatic systolic blood pressure was lower in those with progressive cerebral ischemia. These facts show that the marked drop in orthostatic blood pressure may be related to cerebral ischemic lesions and that the combination of OH and LV may develop cerebral ischemia in older patients with transient orthostatic syncope.

Relationship between endothelin-1 extraction in the peripheral circulation and systemic vascular resistance in patients with severe congestive heart failure

OBJECTIVES

This study was done to determine the spillover and extraction of endothelin-1 (ET-1) in the peripheral circulation, and to evaluate the factors that regulate local ET-1 extraction in the peripheral circulation in patients with congestive heart failure (CHF).

BACKGROUND

The relationship between the spillover and extraction of the ET-1 in the peripheral circulation and systemic vascular resistance (SVR) has not been fully clarified.

METHODS

We measured plasma levels of ET-1 both in femoral artery (FA) and femoral vein (FV) in 93 patients with CHF.

RESULTS

Plasma ET-1 was significantly higher in FV than in FA in New York Heart Association (NYHA) functional class II patients, but there was no difference of ET-1 between FA and FV in functional class III patients. In patients with functional class IV, plasma ET-1 was significantly lower in FV than in FA, and SVR was significantly higher than in patients with NYHA class II or class III. Moreover, a significant positive correlation existed between plasma ET-1 extraction across the lower leg and SVR in these patients. Among the various neurohumoral factors and hemodynamics, plasma levels of ET-1, angiotensin II in the FA showed an independent and significant relationship with the plasma arteriovenous difference of ET-1 in the lower limb.

CONCLUSIONS

Circulating ET-1 is extracted in peripheral circulation in patients with severe CHF, suggesting the possibility of upregulation of ET receptors of vascular beds in the lower limb in these patients. The peripheral extraction of ET-1 correlates with SVR in severe CHF patients and is mainly regulated by the local ET-1 and renin angiotensin systems.

Asymptomatic familial cerebral aneurysms

PURPOSE

We evaluated the prevalence and features of cerebral aneurysms in the family members of people with asymptomatic aneurysms among 8680 participants undergoing magnetic resonance angiography.

METHODS

Of the 8680 participants, 380 had family histories of aneurysms and 8300 did not. The prevalence and features of asymptomatic aneurysms were compared in these two subgroups. In addition, the prevalence in all living first- or second-degree relatives was evaluated in 20 families.

RESULTS

The prevalence of asymptomatic aneurysms was 7.0% (606 of 8680 participants) overall and 10.5% (40 of 380 participants) and 6.8% (566 of 8300 participants) in the subgroups with and without family histories of aneurysms, respectively. The prevalence in the female participants with family histories of aneurysms (12.3%, 28 of 228 participants) was higher than that in the male participants with family histories of aneurysms (7.9%, 12 of 152 participants) (P < 0.0001). Compared with the entire group, this subgroup more commonly showed aneurysms situated at the junction of the internal carotid and posterior communicating arteries (P < 0.0005) and at the middle cerebral artery (P < 0.0001). The prevalence of aneurysms in 115 members of the 20 families was 33.9%. Although the members of 14 families with aneurysmal subarachnoid hemorrhage showed higher prevalence of ruptured and asymptomatic aneurysms (42.1%) than did the members of 6 families with only asymptomatic aneurysms (17.9%), the former had very low prevalence of asymptomatic aneurysms.

CONCLUSION

The prevalence of aneurysms is significantly elevated in family members of people with asymptomatic aneurysms. It is suggested that familial asymptomatic aneurysms are more likely to rupture in families having members with aneurysmal subarachnoid hemorrhage than in those without.

[Anesthetic management for microlaryngeal surgery with high frequency jet ventilation and intravenous application of pentazocine and propofol]

Microlaryngeal surgery was performed with total intravenous anesthesia using pentazocine and propofol in 20 patients. The patients were paralyzed by suxamethonium infusion and ventilated by high frequency jet ventilation via the laryngoscope. In place of the opioid analgesics commonly used in TIVA for microlaryngeal surgery, pentazocine was given. All but one of the patients received pentazocine 15 m.g. intramuscularly as a premedication and then another 15 m.g. intravenously for induction of anesthesia. Average time of surgeries was 33.6 minutes. Average doses of pentazocine and suxamethonium given during surgeries were 369 m.g. and 286 m.g., respectively. This technique allowed stable anesthesia to be achieved with rapid postoperative recovery, without serious complications like intraoperative return of awareness.

Interleukin-6 spillover in the peripheral circulation increases with the severity of heart failure, and the high plasma level of interleukin-6 is an important prognostic predictor in patients with congestive heart failure

OBJECTIVES

We 1) evaluated whether interleukin-6 (IL-6) is produced in the peripheral circulation in patients with congestive heart failure (CHF), 2) estimated the factors for increased IL-6, and 3) clarified the prognostic role of high plasma levels of IL-6 in patients with CHF.

BACKGROUND

Although plasma levels of IL-6 have been reported to increase in patients with CHF, and production of IL-6 in endothelial cells and vascular smooth muscle cells has been postulated from in vitro studies, the origin of the increase of IL-6 in CHF remains unknown. Moreover, the prognostic value of a high plasma level of IL-6, independent of classic neurohumoral factors, remains to be elucidated.

METHODS

A comparison was made of the plasma levels of IL-6 between the femoral artery and the femoral vein in 13 normal subjects and in 80 patients with CHF. In another study, we measured plasma IL-6 in 100 patients with CHF and follow-up data.

RESULTS

Plasma IL-6 levels increased significantly from the femoral artery to the femoral vein in normal subjects and in patients with CHF. Arteriovenous IL-6 spillover in the leg increased with the severity of CHF. Among the hemodynamic variables and the various neurohumoral factors, the plasma norepinephrine (NE) level showed an independent and significant positive relation with the plasma IL-6 level in patients with CHF. Moreover, treatment with beta-adrenergic blocking agents showed an independent and significant negative relation with plasma IL-6 levels. In 100 patients, plasma IL-6 (p < 0.0001), NE (p = 0.0004) and left ventricular ejection fraction (0.015) were significant independent prognostic predictors by Cox proportional hazards analysis.

CONCLUSIONS

Our findings indicate that the IL-6 spillover in the peripheral circulation increases with the severity of CHF and that the increase in plasma IL-6 is mainly associated with the activation of the sympathetic nervous system. High plasma levels of IL-6 can provide prognostic information in patients with CHF, independent of left ventricular ejection fraction and plasma NE, suggesting an important role for IL-6 in the pathophysiology of CHF.

Digitalis increases brain natriuretic peptide in patients with severe congestive heart failure

Ouabain can cause increased secretion of atrial natriuretic peptide (ANP) from atrial cardiocyte culture, but the effects of digitalis in a therapeutic range on the secretion of cardiac natriuretic peptide including ANP and brain natriuretic peptide (BNP), mainly from the ventricle, in patients with congestive heart failure remain to be investigated. Therefore we studied the acute effects of intravenous infusion of a relatively low dose of digitalis or placebo on hemodynamics and neurohumoral factors including the plasma levels of ANP and BNP and cyclic guanosine monophosphate, a second messenger of cardiac natriuretic peptide, in 13 patients with severe congestive heart failure. No significant change in the hemodynamic parameters or neurohumoral factors was observed with placebo. After 1 hour of intravenous administration of deslanoside (0.01 mg/kg), there was a significant decrease of plasma renin activity and angiotensin II, aldosterone, and norepinephrine levels but no significant change of plasma levels of vasopressin and a significant decrease of the pulmonary capillary wedge pressure but no significant change in cardiac index. In addition, plasma levels of ANP (217 +/- 47 vs 281 +/- 70 pg/ml, p < 0.05), BNP (628 +/- 116 vs 689 +/- 132 pg/ml, p < 0.05), and cyclic guanosine monophosphate (9.7 +/- 1.1 vs 10.9 +/- 1.5 pmol/ml, p < 0.05) increased despite the decrease of pulmonary capillary wedge pressure (19.7 +/- 2.3 vs 16.8 +/- 2.3 mm Hg, p < 0.05). These results indicate the acute intravenous low dose of digitalis resulted in a significant increase in plasma levels of ANP, BNP, and cyclic guanosine monophosphate concomitant with the significant decrease of pulmonary capillary wedge pressure, suggesting the acute direct action of digitalis on the cardiac natriuretic peptides released from the heart in patients with severe congestive heart failure.

[Efficacy of MR angiographic original images on surgery for posterior communicating artery aneurysms]

This study evaluated the usefulness of axial source images of magnetic resonance angiography (MRA) on preoperative depiction of surgical topography around posterior communicating artery aneurysms. Twenty patients with posterior communicating artery aneurysms, two ruptured and eighteen unruptured, underwent conventional angiography as well as axial source and projection images obtained by three-dimensional time-of-flight MRA techniques. By comparing the topography based on these angiograms to that confirmed during surgery, we evaluated useful information specific to the source images of MRA. Source images of MRA visualized the posterior communicating artery and the anterior choroidal artery in eighteen cases (90%) and five cases (25%), respectively. The posterior communicating artery was recognized at a higher rate by source images of MRA than by conventional angiography (65%), while the anterior choroidal artery was recognized at a lower rate than by combined angiography (75%). We realized some specific information to the source images of MRA including the topographical relations between the aneurysmal neck and the orifice of the posterior communicating artery, the relations between the aneurysmal dome and the oculomotor nerve and the aneurysmal dome buried into the temporal lobe. The information suggested a satisfactory direction of safe aneurysmal clipping so as not to occlude the posterior communicating artery. It was concluded that the source images of MRA provided additional useful information on surgical topography in 60% of the cases involving posterior communicating artery aneurysms. Although not essential in every case, the information would be beneficial in cases with the aneurysmal dome suspected to be in the temporal lobe or when the surrounding topography can not be clearly understood by angiography.

MR angiography of intracranial aneurysms: a comparison of 0.5 T and 1.5 T

The objective of this paper is to compare the diagnostic efficacy of 3 DFT time-of-flight MR angiography (MRA) at middle-field-strength and high-field-strength in diagnosis of intracranial aneurysms. Thirty-one patients, including 26 patients with angiographically confirmed intracranial aneurysms (n = 28), underwent MRA at 0.5 and 1.5 T. Images were interpreted by six trained observers who were blinded to diagnosis. Twelve projections of MRA of the circle of Willis, by maximum-intensity projection algorithm, were reviewed using continuous confidence-judgement scales. It was found that MRA at 1.5 T was more sensitive than that at 0.5 T in detection of aneurysms. The sensitivity of six observers ranged between 50 and 64% (mean 56%) at 0.5 T, and between 61 and 86 86% (mean 75%) at 1.5 T. In the smaller aneurysms less than 5 mm, the differences between the units became greater. The sensitivity for small aneurysms ranged from 23 to 54% (mean 32%) at 0.5 T, and from 31 to 69% (mean 58%) at 1.5 T. Our conclusion was that high field strength confers higher accuracy in the detection of intracranial aneurysms with MRA with current-generation MR imagers.

Intracranial vascular stenosis and occlusion: MR angiographic findings

PURPOSE

To investigate whether obtaining axial source images from three-dimensional Fourier transform (3DFT) time-of-flight MR angiography improves the detection of intracranial vascular stenosis and occlusion if added to maximum-intensity projection (MIP) images.

METHODS

The angiograms of 103 patients who had MR angiography for evaluation of possible intracranial vascular disease were reviewed retrospectively in a quantitative and nonquantitative fashion. Diameters of vessels on MR angiograms were measured quantitatively by two reviewers using a magnifying loupe and compared with the results from conventional angiograms. Degrees of stenoocclusive disease were categorized into five classes; an artery with stenosis of 50% or greater was considered to be diseased. Another five observers also reviewed the MIP images with and without source images in a blinded fashion by means of nonquantitative visual inspection.

RESULTS

In all, 23 stenoocclusive lesions of 50% or greater were available for review. In the quantitative analysis, with MIP images alone, 14 (78%) of 18 moderate and severe stenoses and four (80%) of five occlusions were identified correctly. The addition of the source images increased the sensitivity to 100% for moderate and severe stenoses and to 100% for occluded vessels. In the visual inspection study, however, no statistically significant differences were found between interpretations of MIP images alone and those of MIP images in combination with source images.

CONCLUSION

In the quantitative study, interpretation of source images rather than MIP images reduced the tendency to overestimate stenosis seen with MR angiography and improved the sensitivity for detecting stenosis of 50% or greater. There was a discrepancy between the quantitative study and visual inspection. Experienced observers had a tendency to underestimate the degree of stenosis.

Intracranial aneurysms: diagnostic accuracy of MR angiography with evaluation of maximum intensity projection and source images

PURPOSE

To determine whether evaluation of source images from magnetic resonance (MR) angiography in addition to maximum-intensity projection (MIP) images improves the detection of aneurysms.

MATERIALS AND METHODS

Conventional and MR angiography were performed in 193 patients with various intracranial vascular lesions or normal findings. Images were evaluated in a blinded manner. Two readings were performed 6 weeks apart by evaluating MIP images with and without source images. Results were evaluated with receiver operating characteristic analysis.

RESULTS

Sensitivity for the detection of aneurysms increased slightly when source images were included. The detection rate of internal carotid artery aneurysms was most improved with the addition of source images. No statistically significant differences in performance were found between the readings with MIP images alone and with source images.

CONCLUSION

Sensitivity may improve with combined reading of nonselective MIP and source images.

Intracranial aneurysms: diagnostic accuracy of three-dimensional, Fourier transform, time-of-flight MR angiography

PURPOSE

To assess the accuracy of three-dimensional, Fourier transform, time-of-flight magnetic resonance (MR) angiography in the identification of intracranial aneurysms.

MATERIALS AND METHODS

MR angiograms of 126 patients (59 male and 67 female patients, aged 12-77 years) with various intracranial vascular lesions were evaluated. Seventy-eight aneurysms, including 60 less than 5 mm in diameter, in 61 patients were depicted at conventional angiography. Eight projection images, as well as one axial collapsed MR angiogram obtained with a maximum-intensity projection algorithm, were used for evaluation.

RESULTS

Sensitivity for the five observers ranged from 58% to 68% (mean, 63%). Higher sensitivity was achieved for anterior communicating and middle cerebral artery aneurysms, while that for internal carotid artery aneurysms was poor. Sensitivities for small and medium aneurysms ranged from 50% to 60% (mean, 56%) and from 77% to 94% (mean, 86%), respectively.

CONCLUSION

MR angiography can depict intracranial aneurysms 5 mm or larger with good accuracy but is less useful for the identification of smaller aneurysms.

Intracranial vascular stenosis and occlusion: diagnostic accuracy of three-dimensional, Fourier transform, time-of-flight MR angiography

PURPOSE

To assess the accuracy of three-dimensional, Fourier transform, time-of-flight magnetic resonance (MR) angiography in the detection of intracranial steno-occlusive diseases.

MATERIALS AND METHODS

One hundred thirty-one patients (62 male and 69 female patients, aged 6-77 years [mean, 53 years 8 months]) underwent MR and conventional angiography for evaluation of possible intracranial vascular disease. A total of 502 arteries were assessed. Eight projections and a collapsed image postprocessed by means of a maximum-intensity projection algorithm were reviewed by five observers in a blinded manner, with conventional angiography as the standard.

RESULTS

A total of 32 steno-occlusive lesions were available for review. Receiver operating characteristic analysis from the pooled data revealed overall sensitivities of 85% and 88% and specificities of 96% and 97% for the internal carotid artery and the middle cerebral artery, respectively.

CONCLUSION

MR angiography is useful as the primary diagnostic tool for evaluating suspected intracranial steno-occlusive disease.

[Volume measurement of the horizontal extraocular muscles using magnetic resonance imaging]

The volume of the horizontal extraocular muscles of 11 normal adults and three patients with ophthalmoplegia was measured using magnetic resonance imaging (MRI). The MRI examinations were carried out with a Signa Advantage, 1.5 tesla superconductive magnetic system manufactured by General Electric. This method employs the spin echo technique with a 3.0 mm gapless slice, a 350 ms. repetition time, and a 17.0 ms. echo time. The MRI films were projected and magnified on Kent paper using an overhead projector. Then the shapes of the horizontal extraocular muscles were traced. The volume of the muscles was measured as the total weight of Kent papers which were cut out from muscle shapes in all the slices. The average volume of the normal medial and lateral rectus muscles was 690 +/- 87 mm3 and 734 +/- 77 mm3, respectively. Two cases with peripheral nerve palsy showed typical atrophy of the paretic muscles. A case with orbital myositis showed typical hypertrophy of the inflamed muscles. This measurement may prove useful in the analysis and evaluation of extraocular muscles, especially in ophthalmoplegia.

[The significance of Gd-DTPA-enhanced MR imaging in endometrial carcinomas]

To evaluate the feasibility of Gd-DTPA-enhanced magnetic resonance (MR) imaging combined with dynamic study in the diagnosis of endometrial carcinomas, we performed MR studies on five healthy volunteers, 17 patients with histologically proved endometrial carcinomas and three patients with atypical hyperplasia of the endometrium. While adenocarcinomas of endometrium were less enhanced than myometrium after Gd-DTPA, clear cell adenocarcinomas became enhanced and isointense to myometrium. The lesions of atypical endometrial hyperplasia were more enhanced than myometrium. Dynamic study using Gd-DTPA offered no further yielding information in those lesions. The results suggest that Gd-DTPA-enhanced MR imaging is an important method in the diagnosis of endometrial carcinomas and differentiation among an adenocarcinoma of the endometrium, a clear cell adenocarcinoma and atypical endometrial hyperplasia.

[MR imaging of optic neuritis using short T1 IR (inversion recovery)]

We evaluated the ability of MRI using short T1 inversion recovery (STIR) to diagnose optic neuritis. Eleven patients with previous or recent attack of optic neuritis were studied with MRI at 0.5 tesla. STIR images revealed high signal regions in 7 of 12 symptomatic and 5 of 10 asymptomatic nerves. Three of five asymptomatic nerves with high intensity were pertinent to the cases with past attack and seemed to reflect the demyelinating change. The other two nerves were pertinent to the cases without past attack and seemed to show occult lesions. We consider that STIR is useful in detection of optic nerve lesions associated with optic neuritis.

Successful extracorporeal lung assist (ECLA) for a patient with severe asthma and cardiac arrest

A 20-year-old male had a severe asthma attack complicated by a cardiac arrest despite maximal conventional therapy including mechanical ventilation. He was treated successfully with emergency veno-arterial Extra-corporeal Lung Assist started after 30 minutes of cardiopulmonary resuscitation. We believe that ECLA is a life-saving measure for intractable asthma and cardiac arrest.

MR imaging of the liver before and after transcatheter hepatic chemo-embolization for hepatocellular carcinoma

Transcatheter chemo-embolization (TCE) in hepatocellular carcinoma (HCC) was performed in 38 patients. The patients were examined by MR imaging before TCE as well as one week and 4 to 5 weeks after TCE. The tumor signal intensity in T2 weighted images increased in 13 cases and decreased in 19 cases after TCE. Increased intensity seemed to reflect intra-tumoral hemorrhage or liquefaction accompanying tumor necrosis. Decreased intensity seemed to reflect coagulation necrosis. In 9 of 18 cases followed over a 2-month period the signal intensity had decreased in both T1 and T2 weighted images. In these patients the tumor showed no recurrence at angiography and the decreased signal seemed to reflect the completion of coagulation necrosis. A hyper- and/or hypointense rim around the tumor appeared in 22 cases. These changes were thought to be perifocal edema or granulation tissue around the tumor. MR imaging was useful in evaluating the necrotic process of the tumor after TCE.

[MRI of lymphedema using short-TI-IR (STIR)]

Thirty four cases with lymphedema of the extremities were examined with MRI at 0.5 tesla. On T1-weighted image, the enlarged subcutaneous tissue and the subcutaneous trabecular structures were seen in all cases. Moreover, the trabecular structures in the enlarged subcutaneous tissue showed low signal intensity on T1-weighted image and high signal intensity on T2-weighted image in all cases. Additionally, in 12 of 15 cases examined by Short-TI-IR (STIR) image, the trabecular structures and fluid collections in the subcutaneous tissue were shown more definitely in high signal intensity than by T2-weighted image. We consider MRI using STIR is to be useful in the evaluation of edematous disease.

[Evaluation of fast MR imaging with suspended respiration in hepatic tumors]

The purpose of this study is to evaluate the possibility of qualitative diagnosis in hepatic tumors by fast magnetic resonance (MR) imaging with suspended respiration using partial flip angle and gradient echo technique at 0.5 T. Fast MR imaging does not replace conventional spin-echo procedures, but is complementary to it. For the analysis of contrast as a function of flip angle, 32 hepatocellular carcinomas (HCCs) of nodular type and 11 hemangiomas were examined with flip angles of 20, 40 and 60 degrees on sagittal images. In general, the lesions showed relatively high and low intensities on the images with flip angles of 20 and 60 degrees, respectively. On the images with flip angle of 40 degrees, signal-to-noise (S/N) ratio was higher, but contrast between tumor and liver was lesser than with that of other angles. The change of contrast-to-noise (C/N) ratio between the flip angles of 20 and 60 degrees in hemangiomas was larger than that in HCCs, significantly. It was useful for evaluation of lesions to observe the change of C/N ratio, and it was necessary for detection of lesions to obtain the images with at least three flip angles. For dynamic MR imaging, 18 HCCs including 5 cases after transcatheter chemoembolization (TCE) and 5 hemangiomas were examined with flip angle of 40 degrees. With employment of Gd-DTPA, S/N ratio and contrast were improved in many cases, and hemodynamics of tumors was able to be observed. It was suggested that dynamic MR imaging was useful especially in evaluation of efficacy of TCE using lipiodol.

[MR imaging of orbital tumors]

Nine cases of pathologically confirmed orbital tumors were evaluated with magnetic resonance imaging (MRI) at 0.5T. Seven cases were examined with orbit-coil using 7-mm-thick sections and two cases were examined with head-coil using 10-mm-thick sections. All lesions were clearly demonstrated on T1-weighted images as low intensity. However, the lesions were indistinct on T2-weighted images because of low contrast between the lesions and surrounding orbital fat and artefact produced by eye movement. Two of three cases with meningioma examined with orbit-coil were clearly discriminated from the optic nerve. Meningioma in the remaining case examined with head-coil was discriminated from the optic nerve by administration of Gd-DTPA. Adenoma of the right lacrimal gland was shown as an enlarged gland on T1-weighted images. Pseudotumors (four cases) showed very low intensity on T1-weighted images. Three cases of four pseudotumors showed low intensity on T2-weighted images. Among them one was moderately low intensity, and histological examination of the lesion showed prominent fibrotic changes. Pseudotumor of the remaining case examined with the head-coil showed same intensity with fat on T2-weighted images. Intraorbital infiltrating foci of chronic lymphocytic leukemia showed low intensity with fat on T1-weighted images, and the same intensity with fat on T2-weighted images. MRI may be useful to discriminate pseudotumor with fibrotic changes (chronic inflammatory lesions) from lymphoma or leukemic infiltration.

[MR imaging of hepatocellular carcinoma following transcatheter hepatic chemo-embolization]

Transcatheter chemo-embolization (TCE) for hepatocellular carcinoma (HCC) was performed on 31 patients, and on 4 of the 31 patients, it was performed twice. The patients were examined by MR both before TCE and after TCE (1 week and 4-5 weeks respectively). On MR images, the change of the tumor signal intensity was classified into 3 groups. In group 1, (G1, 8 cases), obvious change of intensity was seen in the whole tumor. In group 2, (G2, 10 cases), it was seen in some parts of the tumor and in group 3, (G3, 17 cases), only a very slight change of intensity was seen in the whole tumor. In G1 and G2, the rate of AFP decrease was remarkable, but in G3, it was very slight. In G1 and G2, the change of the tumor signal intensity was divided into 2 types on a T2 weighted image. One, is the increase of the intensity, (6 cases). The other, is decrease of intensity, (12 cases). The former seemed to reflect the intra-tumoral hemorrhage accompanying tumor necrosis, the latter, seemed to reflect the coagulation necrosis. The ring of low and high intensity around the tumor appeared anew in 11 cases, and in 2 cases, it increased in size. These changes which have never been recognized on CT images, were thought to be a granulation tissue around the tumor. The influence of the accumulated lipiodol is slight for the change of intensity on the tumor.

[Clinical comparison of 99mTc-diethylenetriaminepentaacetic acid-human serum albumin (99mTc-HSA-D) and 99mTc-human serum albumin (99mTc-HSA) for cardiac blood pool imaging]

99mTc-HSA-D has been developed as a new blood pool scanning agent. Clinical comparison of 99mTc-HSA-D and 99mTc-HSA was made in 16 cases. The activity concentration of 99mTc in blood was measured during 2 hours after the injection in five cases. 99mTc-HSA-D showed higher concentration compared to 99mTc-HSA with the passage of time. Quantitative analysis of contrast between left ventricle and septum was performed on end diastolic frames of gated images 10 minutes after the injection. There was no obvious difference between 99mTc-HSA-D and 99mTc-HSA. The subjective comparison of detectability of lesions between the two agents was performed on three directional gated images. 99mTc-HSA-D was superior to 99mTc-HSA, because the images of the latter deteriorated with the passage of time. On anterior view images 1 hour after the injection, left ventricle/lung and abdominal aorta/background count ratios were greater for 99mTc-HSA-D in many cases. There was no obvious difference in liver/background and kidney/background count ratios between the two agents. Urinary excretion of 99mTc was considerably lesser for 99mTc-HSA-D. The results indicated that 99mTc-HSA-D was superior to 99mTc-HSA for cardiac blood pool imaging.