A patient who developed toe necrosis due to poor blood circulation after an interdigital tick bite

A 71-year-old female had worked on a farm in the mountains and noticed itching of the left 3rd toe. She visited a local hospital due to a color change to purple in this area. Attachment of a tick was observed between the left 2nd and 3rd toes, and it was extracted. However, due to persistent pain, she was referred to our department of cardiovascular medicine for close examination and treatment. Lower extremity angiography showed that vascular visualization was poor in the area supplied by the arteries distal to the tick bite site, but the other blood vessels of the toe were clearly visualized. Toe amputation was performed and pathological examination of a surgical specimen revealed that most blood vessels near the necrosis were occluded by thrombi. We speculated that tick bite reactions were associated with thrombogenic vasculopathy. This report shows a patient who developed toe necrosis due to poor blood circulation after an interdigital tick bite.

Comparison of chronic-stage histopathological findings among 3 coronary stents implanted in the same patient

A 73-year-old woman suffering from anterior thoracic pain on exertion presented to our hospital. We performed coronary angiography and noted three stenotic legions in each coronary artery. For each angiographic finding, we implanted a bare metal stent (BMS), sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) into the right coronary artery, left anterior descending and left circumflex coronary arteries, respectively. Nine months later, she died of lung disease, and we could compare the histopathological findings among the three coronary stents. In the drug-eluting stents, very thin intima, infiltration of inflammatory cells, and fibrin deposition were observed, while thick intima and no inflammatory findings were observed in the BMS. Fibrin deposition was more marked in the PES than in the SES. This report shows marked differences in the subsequent pathological course among three stents in the same patient.

Elevated concentrations of pentraxin 3 are associated with coronary plaque vulnerability

BACKGROUND

Inflammation is a critical contributing factor to the development and progression of atherosclerosis. Pentraxin 3 (PTX3) is produced abundantly in atherosclerotic lesions while C-reactive protein (CRP) is mainly produced in the liver. In this study, we investigated whether plasma levels of PTX3 might be a sensitive marker both for the severity of coronary artery disease and vulnerable plaques. Next, we determined whether assays for inflammatory molecules can be used to monitor the therapeutic effects of telmisartan on stabilization of vulnerable atherosclerotic plaques.

METHODS AND RESULTS

We measured PTX3 concentrations in the peripheral and coronary sinus plasma of 40 patients with angina pectoris (AP) and 20 control subjects. Next, in 28 patients with AP, we determined the correlation between levels of inflammatory molecules and the computed tomography (CT) density of plaques as a quantitative index of plaque vulnerability. There was no significant difference in peripheral plasma PTX3 concentrations between patients with AP and control subjects, while coronary sinus plasma PTX3 concentrations were significantly higher in AP patients than control subjects. The concentrations of PTX3 in coronary sinus and peripheral plasma correlated with Gensini scores as an index of severity of coronary atherosclerosis. Interestingly, there was a significantly negative correlation between plasma PTX3 concentrations and CT density (r=-0.67, p<0.01). On the other hand, CT density did not correlate with the peripheral plasma concentrations of monocyte chemoattractant protein-1 (MCP-1) or high-sensitivity CRP (hsCRP). Furthermore, telmisartan treatment for 6 months decreased plasma concentrations of PTX3 but not those of MCP-1 or hsCRP in 12 patients with essential hypertension. Multivariate regression analysis revealed that changes in PTX3 levels were independent of blood pressure changes.

CONCLUSIONS

PTX3 is likely more specific than hsCRP as an indicator of coronary plaque vulnerability that could lead to plaque rupture.

Effect of low-dose (1 mg/day) pitavastatin on left ventricular diastolic function and albuminuria in patients with hyperlipidemia

The aim of the present study was to evaluate the factors that modulate the protective action of statins on cardiorenal function, regardless of the lipid-lowering effect. To treat abnormal serum lipid profiles, low-dose pitavastatin (1.0 mg/day) was administered to 65 hyperlipidemic patients. The exclusion criteria included left ventricular ejection fraction <40% and apparent renal disease. Age- and gender-matched patients with hyperlipidemia (n = 40) served as the controls. After 12 to 16 weeks of pitavastatin treatment, pitavastatin had decreased low-density lipoprotein cholesterol (from 143.5 ± 31.4 to 98.2 ± 19.4 mg/dl, p <0.01), triglycerides (from 157.7 ± 57.2 to 140.5 ± 60.7 mg/dl, p <0.01), E/e' (from 10.8 ± 6.2 to 9.0 ± 4.5, p <0.05), a parameter of left ventricular diastolic function, and albuminuria (from 47.6 ± 55.9 to 28.5 ± 40.0 mg/g creatinine, p <0.01). Furthermore, pitavastatin decreased serum transforming growth factor-β1 (from 709 ± 242 to 550 ± 299 pg/ml, p <0.01), urinary 8-hydroxy-2'-deoxyguanosine (from 6.6 ± 4.1 to 5.0 ± 3.1 μg/g creatinine, p <0.01), an oxidative stress marker, and increased urinary nitrate and nitrite (from 22.5 ± 14.6 to 29.4 ± 27.6 nmol/g creatinine, p <0.05). No such changes were observed in the controls. Multiple regression analysis in the pitavastatin group revealed the effect of pitavastatin on cardiorenal function was associated with suppression of oxidative stress, but not on low-density lipoprotein cholesterol reduction. In conclusion, pitavastatin decreases E/e' and albuminuria, which is associated with suppression of oxidative stress.

Ventricular tachycardia in cardiac sarcoidosis controlled by radiofrequency catheter ablation

We report a case of a 78-year-old woman with cardiac sarcoidosis with a history of syncope and palpitation. Further assessment with echocardiography, gadolinium-enhanced cardiovascular magnetic resonance (CMR) and histology led to a diagnosis of cardiac sarcoidosis. As the patient suffered from ventricular tachycardia (VT) despite active corticosteroid therapy, an implantable cardioverter-defibrillator (ICD) was positioned. She was also administered a beta blocker, but an electrical storm appeared every several days requiring ICD therapy. The drug-refractory VT was finally controlled with a catheter ablation session, during which we could detect the VT focus in the right ventricular outflow tract next to the aneurysm by using an electroanatomic mapping system (CARTO). Referring to echocardiographic and CMR images proved very useful in detecting the aneurysm using the CARTO system.

Diagnostic utility of cardiac magnetic resonance for detection of cardiac involvement in female carriers of Duchenne muscular dystrophy

BACKGROUND

Cardiac involvement is a recognised complication in female carriers of Duchenne muscular dystrophy (DMD). Since segmental or global left ventricle (LV) wall motion abnormalities in DMD carriers can arise even without apparent muscle weakness, it is difficult to differentiate cardiac involvement of a DMD carrier from other heart diseases in a non-invasive manner. Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) enables assessment of regional wall motion abnormality and myocardial damage with high spatial resolution.

OBJECTIVE

To assess the utility of CMR for detection of myocardial damage in female carriers of DMD.

METHODS AND RESULTS

Gadolinium-enhanced CMR was performed in seven female DMD carriers. Physical examination, electrocardiography, chest radiograph, measurements of total creatinine kinase and brain natriuretic peptide levels, and two-dimensional echocardiography were also performed. Four (57%) of the seven carriers had LGE, and LGE was frequently observed at the subepicardial layer in the inferolateral segment. Two carriers had a focal LGE at the LV inferolateral wall without LV dilation or wall motion abnormalities.

CONCLUSION

CMR findings of DMD carriers were characterised by subepicardial LGE, which was localised at inferolateral segments. CMR may be a useful modality for detecting cardiac involvement in DMD carriers.

Ezetimibe ameliorates metabolic disorders and microalbuminuria in patients with hypercholesterolemia

AIM

Ezetimibe, an inhibitor of Niemann-Pick C1-like 1 protein, has been shown to reduce the intestinal absorption of cholesterol. We investigated whether it also has beneficial effects on metabolic disorder and/or renal insufficiency in patients with hypercholesterolemia.

METHODS

Ezetimibe was administered to 38 Japanese patients with hypercholesterolemia to obtain appropriate low-density lipoprotein cholesterol (LDL-chol) levels. Age- and sex-matched patients with hypercholesterolemia (n=38) were the controls. We evaluated the effects of ezetimibe before and 4 to 8 weeks after ezetimibe treatment.

RESULTS

Ezetimibe significantly decreased LDL-chol levels and metabolic syndrome-related factors, including body weight, waist circumference, blood pressure; homeostasis model assessment insulin resistance (HOMA-IR), and urinary albumin excretion, were significantly reduced. In addition, it decreased the level of high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor (TNF)-alpha, the urinary excretion of 8-hydroxy-2'-deoxyguanosine, a parameter of oxidative stress, and increased the urinary excretion of nitrate and nitrite (NOx). In the controls we observed no such changes. Excepting the decrease in the serum TNF-alpha level, the effects of ezetimibe were not correlated with decreased LDL-chol levels.

CONCLUSION

Ezetimibe ameliorated the status of metabolic syndrome and microalbuminuria, reduced inflammation and oxidative stress, and increased nitric oxide bioavailability in a LDL-chol reduction-dependent and -independent manner.

Congenital ventricular aneurysm as an unexpected complication of monomorphic premature ventricular contractions

Congenital ventricular diverticulum (CVD) in adults is a rare cardiac malformation, which includes fibrous type congenital ventricular aneurysm (CVA). CVA is often clinically asymptomatic and shows no abnormality in the electrocardiogram or chest X-ray. However, some cases of sudden death resulting from ventricular tachycardia, cardiac embolism or ventricular rupture have been reported. Therefore, physicians should perform further cardiac imaging studies to detect a CVA if ventricular arrhythmia originating from the left ventricle is observed. Here, we report two successfully followed cases of CVA which were diagnosed from premature ventricular contractions.

Bosentan ameliorated exercise-induced pulmonary arterial hypertension complicated with systemic sclerosis

Pulmonary arterial hypertension (PAH) is a frequent complication in patients with systemic sclerosis. Bosentan is used in patients with symptomatic PAH; however, it has not been established whether or not bosentan ameliorates the progression of PAH in patients with no PAH-related symptoms. We present a case of systemic sclerosis with no PAH-related symptoms in which bosentan ameliorated exercise-induced PAH evaluated by 6-minute walk stress echocardiography, brachial flow-mediated dilation, and skin temperature of hands and feet. The results suggest that administration of bosentan in patients with early-stage PAH ameliorates pulmonary arterial vasodilatation through improvement of endothelial function.

Functional analysis of neurosteroidal oestrogen using gene-disrupted and transgenic mice

The brain aromatase (oestrogen synthase) hypothesis predicts that oestrogen plays important roles in both sexual behaviours and brain sexual differentiation. To elucidate the functions of oestrogen in the brain, we generated aromatase knockout (ArKO) mice, which showed undetectable oestrogen and enhanced androgen levels in blood. These ArKO mice exhibited an enhanced appetite and disorders in sexual motivation, sexual partnership preference, sexual performance, aggressive behaviour, parental behaviour, infanticide behaviour and exploratory (anxiety) behaviour. We characterised the brain-specific promoter of the mouse aromatase gene, and identified several crucial cis-acting elements and the minimal essential promoter region for brain-specific expression. Next, we introduced a transgene of human aromatase, controlled by the minimal promoter region, into the ArKO mouse. The resulting mouse (ArKO/hArom), whose preoptic area, hypothalamus and amygdala were exposed to oestrogens only in the perinatal period, and then to enhanced androgens and no oestrogens in adulthood, showed near recovery from behavioural disorders. These results suggest that local oestrogens acting in specific brain regions are involved in the organisation of sex-specific neural networks during the perinatal period. Finally, we examined effects of oestrogens on gene expression within specific brain regions in mice during the perinatal period using DNA microarray analysis. This assay revealed both up-regulated and down-regulated brain-specific genes, including those related to neuronal function. Specifically, genes involved in energy metabolism, cell proliferation/apoptosis and secretory/transport system were altered in ArKO mice compared to wild mice. These results suggest that brain oestrogens participate in the sexual differentiation of the brain by influencing gene expression.

Assessment of abnormal left atrial relaxation by transesophageal pulsed Doppler echocardiography of pulmonary venous flow velocity

BACKGROUND

Several studies on left ventricular relaxation have been undertaken in the past; however, left atrial (LA) relaxation has not been fully evaluated.

HYPOTHESIS

The purpose of this study was to assess abnormalities in LA relaxation by evaluating pulmonary venous flow velocity and interatrial septal motion using transesophageal echocardiography.

METHODS

The subjects were 56 untreated patients in sinus rhythm, including 25 with previous myocardial infarction, 9 with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy, as well as 11 with chest pain syndrome as controls. Peak first systolic velocity (PVS1), peak atrial systolic velocity (PVA), and their time-velocity integrals (PVS1-I and PVA-I, respectively) were calculated from the pulmonary venous flow velocity.

RESULTS

The PVS1 and PVS1-I correlated negatively with the maximum LA dimension and mean pulmonary capillary wedge pressure, and correlated positively with the amplitude of the interatrial septal motion during LA relaxation and percent fractional LA relaxation. The PVA and PVA-I did not correlate with the mean pulmonary capillary wedge pressure. There was a weak positive correlation between PVA and PVS1, and a close positive correlation between the ratio of PVA to PVS1 and mean pulmonary capillary wedge pressure. Multiple regression analysis indicated that the PVS1 was most closely related to percent fractional LA relaxation, followed by mean pulmonary capillary wedge pressure.

CONCLUSION

The PVS1 determined from the pulmonary venous flow velocity is closely related to parameters of LA relaxation which may be determined by transesophageal M-mode echocardiography, and the ratio of PVA to PVS1 is useful for noninvasive evaluation of LA pressure.

Evaluation of left atrial filling using systolic pulmonary venous flow velocity measurements in patients with atrial fibrillation

BACKGROUND

The pattern of pulmonary venous flow velocity is useful for understanding the hemodynamic relationship between the left atrium and left ventricle in patients with a variety of diseases, and the systolic flow wave, in particular, is considered a clinically important parameter that reflects left atrial filling.

HYPOTHESIS

The study was undertaken to determine whether systolic pulmonary venous flow velocity patterns can be used to evaluate left atrial filling in patients with atrial fibrillation.

METHODS

We performed transesophageal pulsed Doppler echocardiography and cardiac catheterization in 34 patients with chronic atrial fibrillation (10 with hypertrophic cardiomyopathy, 5 with dilated cardiomyopathy, 7 with previous myocardial infarction, and 12 with isolated atrial fibrillation) and 15 normal controls in sinus rhythm.

RESULTS

Mean pulmonary capillary wedge pressure, V-wave height in the pulmonary capillary wedge pressure curve, and left ventricular end-diastolic pressure were significantly higher in the hypertrophic cardiomyopathy and dilated failing heart (previous myocardial infarction and dilated cardiomyopathy) groups than in the isolated atrial fibrillation and normal groups. The peak velocity and time-velocity integral of the systolic pulmonary venous flow velocity, and percent left atrial emptying fraction were significantly lower in the dilated failing heart group than in the isolated atrial fibrillation, hypertrophic cardiomyopathy, and normal groups. The peak velocity and time-velocity integral of the systolic pulmonary venous flow velocity, percent left atrial emptying fraction, and V-wave height were comparatively constant when the preceding R-R intervals were relatively stable in the isolated atrial fibrillation group and in 4 of the 10 patients with hypertrophic cardiomyopathy. However, changes in these variables correlated with the preceding R-R interval in all patients with dilated failing hearts and in 6 of the 10 patients with hypertrophic cardiomyopathy.

CONCLUSION

Transesophageal pulsed Doppler echocardiographic measurements of systolic pulmonary venous flow velocity are valid indicators of left atrial filling in patients with atrial fibrillation.

Acute myocardial infarction in a patient with essential thrombocythemia who underwent successful stenting--a case report

Essential thrombocythemia (ET) can cause systemic vascular thrombosis, but involvement of coronary arteries in the setting of ET is rare. This report describes a case of acute myocardial infarction (MI) in a patient with ET. A 67-year-old man with ET complained of severe acute chest pain. Emergent coronary angiography revealed subtotal thrombotic occlusion of the left main trunk (LMT) coronary artery. Coronary angioplasty and stenting were performed successfully. Coronary angiography 4 weeks later revealed no significant restenosis. The patient has done well after primary coronary stenting with the use of only an antiplatelet agent to treat the thrombocythemia.

Risk factors for postoperative delirium in patients undergoing head and neck cancer surgery

This study was carried out to determine risk factors for delirium after major head and neck cancer surgery. The postoperative experience of 38 patients who underwent major head and neck cancer surgery and were managed in the high care unit was retrospectively examined by reviewing their medical records. Delirium was defined as confusion and abnormal behavior that interfered with postoperative recovery. Postoperative delirium occurred in 10 patients (26.3%) who all had stage IV cancer, flap reconstruction, an operative time of more than 10 h, blood transfusion of more than 4 units or infusion of more than 5000 ml, which together suggested the risk of delirium increased significantly with extensive surgery. Delirium occurred less frequently in patients with minor tranquilizer use for postoperative sleep disorder. Multivariative analyses showed an operative time of >10 h and no use of minor tranquilizer as significant factors for increasing the incidence of delirium, with odds ratios (95% confidence interval) of 11.4 (1.5-83.8) and 9.8 (1.5-66.0), respectively.

Phenotypic screening for pharmaceuticals using tissue constructs

Compounds can be screened for pharmaceutical activity either by detecting interactions with specified target molecules such as receptors or enzymes (molecular screening) or observing effects on the structure or physiological activities of cells or tissues (phenotypic screening). Screening at the molecular level has been greatly enhanced by fluorescence methods. Especially the combination of confocal detection with measurements of the amplitudes and time courses of fluorescence fluctuations have reduced sample volumes to < microliters and have increased throughputs to >100000 compounds per day. Screening at the molecular level, however, does not provide information about the effects of test compounds on cellular functions. Phenotypic screening, although much slower than molecular screening, does provide information about effects on cell or tissue structure or function and therefore can be used to eliminate at an early stage compounds that are toxic or do not produce the desired cellular response. Tissue constructs reconstituted using cells of specified types and defined extracellular matrix components provide test systems for detecting the effects of test compounds on cellular mechanical functions such as the development of contractile force and on cell and matrix structure and stiffness. For example, constructs based on vascular smooth muscle cells provide information about effects on cellular contractile force that can be used to identify agents that control blood pressure. Tissue constructs that mimic skeletal, smooth and heart muscles and connective tissues have been produced and can be used to study mechanical and structural responses to active compounds.

Atrial electrophysiologic abnormalities in patients with Wolff-Parkinson-White syndrome but without paroxysmal atrial fibrillation

BACKGROUND

Paroxysmal atrial fibrillation (PAF) frequently occurs in patients with Wolff-Parkinson-White (WPW) syndrome.

HYPOTHESIS

The purpose of this study was to analyze the atrial electrophysiologic abnormalities and vulnerability to develop atrial fibrillation (AF) in patients with WPW syndrome but with no previous history of PAF.

METHODS

We investigated atrial electrophysiologic abnormalities and vulnerability to AF in patients with WPW syndrome but without PAF. An electrophysiologic study was performed in 28 patients with WPW syndrome, 23 with atrioventricular nodal reentrant tachycardia (AVNRT) and 25 with other arrhythmias (control), all of whom had no history of PAF. The following atrial excitability parameters were assessed: effective refractory period (ERP), spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation (%MAF; A2/A1 x 100), wavelength index (WLI; ERP/A2), and inducibility of AF.

RESULTS

The ERP tended to be shorter in patients with WPW syndrome and in those with AVNRT than in the control group. The %MAF increased (154 +/- 33 vs. 137 +/- 23%, p < 0.05) and WLI decreased (2.7 +/- 0.8 vs. 3.4 +/- 1.0, p < 0.05) significantly in patients with WPW syndrome compared with the control group; however, these parameters in patients with AVNRT showed intermediate values. Atrial fibrillation was more inducible in patients with WPW syndrome (4/28 [14.3%]) than in those with AVNRT (4.3% [1/23]) and the control group (0/25 [0%]). With respect to patients with WPW syndrome and with and without inducible AF, the %MAF increased (195 +/- 23 vs. 148 +/- 30%, p < 0.01) and the WLI decreased (2.2 +/- 0.3 vs. 2.9 +/- 0.9, p < 0.05) in subjects with inducible AF.

CONCLUSIONS

Atrial electrophysiologic abnormalities, especially atrial conduction delays, are more prominent in patients with WPW syndrome, even if they had no previous history of PAF. These abnormalities may play an important role in determining the vulnerability to AF.

Potential application of tissue Doppler imaging to assess regional left ventricular diastolic function in patients with hypertrophic cardiomyopathy: comparison with 123I-beta-methyl iodophenyl pentadecanoic acid myocardial scintigraphy

BACKGROUND

Tissue Doppler imaging (TDI) has been utilized to evaluate left ventricular myocardial dysfunction in patients with hypertrophic cardiomyopathy (HCM); however, no clear explanation for the abnormality of TDI variables has been forthcoming.

HYPOTHESIS

Peak negative myocardial velocity gradient (MVG) derived from TDI may correlate with a disorder of fatty acid metabolism in patients with HCM.

METHODS

Tissue Doppler imaging and 123I-beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP) myocardial scintigraphy were performed in 15 patients with asymmetric septal hypertrophy (mean age 47 +/- 18 years) and in 12 healthy controls (mean age 43 +/- 10 years).

RESULTS

In early 123I-BMIPP images, accumulation defects were observed in the ventricular septum in 12 patients and in the posterior wall in 8 patients with HCM. Peak negative MVG in the ventricular septum (1.1 +/- 0.5 vs. 2.8 +/- 0.5, p < 0.0001) and posterior wall (5.2 +/- 1.4 vs. 6.7 +/- 0.8, p < 0.01 ) was significantly lower in the HCM group than in the controls; also, these parameters were significantly lower in patients with than in those without a defect in the region in question. The peak negative MVG in the ventricular septum and posterior wall correlated inversely with the washout rate in all subjects.

CONCLUSIONS

Peak negative MVG according to TDI is related to disorder of fatty acid metabolism in the regional left ventricular myocardium of patients with HCM.

A patient with sustained ventricular tachycardia: identification of a responder to amiodarone using signal-averaged electrocardiogram

A 75-year-old man suffered sustained ventricular tachycardia with syncopal attack. Ventricular tachycardias appeared repeatedly, and an electrical defibrillator was used after an anti-arrhythmic drug, such as lidocaine or mexiletine, proved ineffective. The tachycardias had multiple origins, and the signal-averaged electrocardiogram (SAECG) showed ventricular late potential before the administration of amiodarone. After administration, the filtered QRS and duration of the late potential increased, but the recurrence of tachycardias was suppressed. The reason for this is thought to be that amiodarone blocked the sodium channel and delayed conduction, consequently blocking reentry, because amiodaron has antiarrhymic properties with a prolongation of refractoriness and minimal effect on conduction velocity in ventricular myocardium, and inhibits sympathetic activity, and blocks L-type calcium channel besides the depression of the fast sodium channel. In this case, SAECG predicted to some degree whether or not this patient's ventricular tachycardia would respond to amiodarone.

Age-related changes in the electrophysiologic properties of the atrium in patients with no history of atrial fibrillation

Although atrial fibrillation is a common arrhythmia, especially in the elderly, little is known about age-related changes in the electrophysiologic properties of the atrium. The aim of this study was to analyze the effect of aging on atrial vulnerability to atrial fibrillation. An electrophysiologic study was performed in 45 patients with no history of atrial fibrillation, Wolff-Parkinson-White syndrome, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiologic function (15 females; mean age, 52 +/- 18 years; range, 14 to 84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation (A2/A1 x 100), effective refractory period, wavelength index (ERP/A2), and inducibility of atrial fibrillation. Atrial fibrillation was induced in 9 patients. Percent maximum atrial fragmentation was greater (176 +/- 36 vs 137 +/- 26%, P < 0.001) and wavelength index was shorter (2.4 +/- 0.4 vs 3.2 +/- 0.9, P < 0.01) in the patients with than without inducible atrial fibrillation. However, age was similar in patients with and without inducible atrial fibrillation (47 +/- 11 vs 53 +/- 19 years, P = 0.36). Percent maximum atrial fragmentation and effective refractory period directly correlated with age (r = 0.32, P < 0.05 and r = 0.45, P < 0.001, respectively). On the other hand, wavelength index (3.1 +/- 0.9) did not correlate with age (r = -0.05, P = 0.77). This study suggests that the mechanism triggering atrial fibrillation may be very well different between older and younger patients with atrial fibrillation, because younger patients have no marked substrate for atrial fibrillation.

Relation of age and sex to atrial electrophysiological properties in patients with no history of atrial fibrillation

Although atrial fibrillation is a common arrhythmia, especially in elderly men, little is known about age related changes in atrial electrophysiological properties or gender differences. The aim of this study was to analyze the effects of aging on vulnerability to atrial fibrillation and assessed gender differences in those age related changes. An electrophysiological study was performed on 73 patients with no history of atrial fibrillation, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiological function, including 25 women (mean age 49 +/- 18 years; range 12-84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation (A2/A1 x 100), effective refractory period, wavelength index (effective refractory period/A2), and inducibility of atrial fibrillation. There were no significant differences in percent maximum atrial fragmentation (143 +/- 28 vs 142 +/- 35%), effective refractory period (241 +/- 39 vs 238 +/- 50 ms), wavelength index (2.9 +/- 0.8 vs 3.1 +/- 0.9), induction of atrial fibrillation (10 [21%] vs 7 [28%]), or age (50 +/- 17 vs 49 +/- 20 years) between men and women. Age was not statistically different between those patients with and without induction of atrial fibrillation in men (48 +/- 14 vs 50 +/- 18 years) and women (48 +/- 18 vs 49 +/- 21 years). Percent maximum atrial fragmentation and effective refractory period were directly correlated with age in men (r = 0.35, P = 0.01; r = 0.46, P < 0.001, respectively) and women (r = 0.42, P = 0.04; r = 0.45, P = 0.02, respectively), though wavelength index did not correlate with age in men (r = -0.04) or women (r = -0.04) with no history of atrial fibrillation. Considering these findings, the authors conclude that the mechanism triggering atrial fibrillation may be different between older and younger patients with atrial fibrillation, because younger patients who have no marked substrate for atrial fibrillation may need many trigger beats to induce atrial fibrillation.

Prognostic value of the atrial systolic mitral annular motion velocity in patients with left ventricular systolic dysfunction

BACKGROUND

Transmitral flow velocity variables are powerful predictors of poor prognosis in patients with left ventricular (LV) systolic dysfunction. However, these variables may not accurately reflect the severity of pulmonary congestion. This study was designed to determine whether the peak atrial systolic mitral annular motion velocity (MA-Aw) measured by pulsed Doppler tissue imaging can predict cardiac death or hospitalization for worsening heart failure in patients with LV systolic dysfunction.

METHODS

MA-Aw was recorded in 96 patients with LV systolic dysfunction who were followed up for 29 +/- 10 months. All patients underwent Doppler echocardiography on entry into the study, and cardiac catheterization was performed in 45 patients. Patients were divided into 3 groups on the basis of the ratio of early (E) to late (A) diastolic filling (E/A) of the transmitral flow velocity: group 1 (n=31; E/A < 1); group 2 (n=37; 1 < or = E/A < 2); and group 3 (n=28; E/A > or = 2).

RESULTS

During follow-up, 36 patients (38%) died of cardiac causes and 34 (35%) were hospitalized for worsening heart failure. There were 2 cardiac deaths (6%) in group 1, 14 (39%) in group 2, and 20 (56%) in group 3. The MA-Aw correlated closely with the mean pulmonary capillary wedge pressure. Univariate Cox model analysis showed that MA-Aw < or = 5 cm/s was the most powerful predictor of cardiac death or hospitalization for worsening heart failure compared with clinical, hemodynamic, and the other echocardiographic variables. Furthermore, MA-Aw < or = 5 cm/s was clearly discernible as a good predictor of cardiac mortality on multivariate Cox model and as assessed by Kaplan-Meier method.

CONCLUSION

The MA-Aw obtained by pulsed Doppler tissue imaging is a sensitive index of pulmonary congestion in patients with LV systolic dysfunction. It is a simple and noninvasive outcome measure and can be used to monitor treatment.

The role of short- and long-axis function in determining late diastolic left ventricular filling in patients with hypertension: assessment by pulsed Doppler tissue imaging

Left ventricular (LV) wall motion velocity during atrial systole is mediated by both transmitral flow and LV myocardial compliance at end-diastole. LV wall distensibility along the long- and short-axis during atrial systole and late diastolic LV filling may vary according to the remodeling of LV morphology. We measured LV wall motion velocities along the long and short axes using pulsed Doppler tissue imaging in 127 patients with hypertension to evaluate the relationship between the hemodynamic changes and LV morphology and to determine the role of both long- and short-axis function in late diastolic LV filling. Participants were classified into 3 groups according to LV dimension and end-diastolic wall thickness determined by M-mode echocardiography: group A (n = 62) without LV dilation or hypertrophy, group B (n = 55) with LV hypertrophy, and group C (n = 10) with LV dilation and systolic dysfunction. The time constant of the LV pressure decay during isovolumic diastole and the LV end-diastolic pressure were longest and greatest, respectively, in group C, compared with groups B and A. There were no significant differences in active left atrial emptying volume during atrial contraction determined by computerized echocardiographic 3-dimensional reconstruction among patient and control groups. The peak atrial systolic motion velocity of the LV posterior wall along the long axis was significantly lower in groups B and C, particularly in the latter group, than in group A. The peak atrial systolic motion velocity of the LV posterior wall along the short axis was greatest in group B and was lowest in group C compared with the other groups, respectively. The peak atrial systolic motion velocity of the LV posterior wall was greater along the long axis than the short axis in group A, but was less than the short axis in group B. In conclusion, the long- and short-axis function of the LV wall during atrial systole varies in patients with hypertension according to the severity of hemodynamic and morphologic abnormalities. The degree of LV wall expansion along the short axis is an important factor resulting from the atrial kick, and a determinant of its effectiveness.

Early systolic mitral annular motion velocities responses to dobutamine infusion predict myocardial viability in patients with previous myocardial infarction

OBJECTIVE

This study was undertaken for the determination of the correlation between myocardial viability and regional systolic mitral annular motion velocity (MAV) response to dobutamine stress in patients with previous myocardial infarction (MI) with pulsed tissue Doppler scan imaging.

METHODS

The study included 45 patients (mean age, 65 +/- 12 years) with previous MI with 1 major coronary lesion and 30 healthy individuals (mean age, 61 +/- 14 years). 99mTc-methoxyisobutylisonitrile scintigraphy was performed to divide the patients into 2 groups: the viability (+) group (n = 25) and the viability (-) group (n = 20). Dobutamine was infused (at 2, 5, 10, and 20 microg/kg/min), and the peak first and second systolic MAVs (Sw1 and Sw2, respectively) were measured at the level of the mitral annulus corresponding to the infarct regions in the MI group and to the 6 mitral annular sites in the control group. In addition, the left ventricular wall motion score index (WMSI) was determined with 2-dimensional echocardiography.

RESULTS

At baseline, the WMSI was significantly greater and the mean Sw1 and Sw2 were significantly lower in both the viability (+) and (-) groups than in the control group, but there were no significant differences between the viability (+) and (-) groups. After dobutamine infusion, the WMSI improved only in the viability (+) group. The mean Sw1 and Sw2 increased significantly with 2 microg/kg/min and 5 microg/kg/min of dobutamine, respectively, in the viability (+) group. With an increase in Sw1 of 2.0 cm/s or more with 5 microg/kg/min of dobutamine, viable myocardium was detected, with a sensitivity of 92% and a specificity of 90%. There were no significant increases in Sw1 or Sw2 in the viability (-) group with dobutamine infusion.

CONCLUSION

Viable left ventricular myocardium is identified with peak early systolic MAV during dobutamine infusion.

Effects of angiotensin II type 1 receptor antagonist (candesartan) in preventing fatal ventricular arrhythmias in dogs during acute myocardial ischemia and reperfusion

Fatal arrhythmias may be prevented by long-term oral administration of angiotensin-converting enzyme (ACE) inhibitors or angiotensin II type 1 (AT 1 ) receptor antagonists. However, there have been no studies evaluating the electrophysiologic changes that occur with the acute administration of AT 1 receptor antagonists during acute myocardial ischemia and reperfusion. This study aimed to evaluate the ability of candesartan to prevent fatal arrhythmias during acute myocardial ischemia and reperfusion. The left anterior descending (LAD) coronary artery was ligated for 10 min and then reperfused for 10 min in 45 adult mongrel dogs. Candesartan (1 mg/kg) or saline was administered intravenously 10 min before ligation of the LAD coronary artery (candesartan group [n = 20] and control group [n = 25], respectively). Changes in ventricular effective refractory period (ERP) and intramyocardial conduction time (ICT) in the risk area were compared during LAD occlusion and reperfusion. Ischemia-induced shortening of ERP was inhibited in the candesartan group compared with the control. There was a 4.7 +/- 5.8% increase in ERP in the candesartan group, compared with a 11.5 +/- 6.3% shortening in the control group (p < 0.01). Prolongation of ICT was inhibited in the candesartan group compared with the control group during both ischemia and reperfusion (maximal prolongation of ICT: 0.1 +/- 3.0% vs. 37.7 +/- 9.6%, respectively; p < 0.01). Incidence of ventricular fibrillation was lower in the candesartan group than in the control group (25% [5/20] vs. 72% [18/25], respectively; p < 0.01). Candesartan suppresses changes in ERP and ICT during acute myocardial ischemia and reperfusion, suggesting that candesartan can prevent the development of fatal arrhythmias.

Characteristic changes of stress protein expression in streptozotocin-induced diabetic rats

Stress proteins (heat shock proteins, HSP) play essential roles in folding, assembly and translocation of polypeptides and also in maintenance of the integrity of polypeptides as molecular chaperones. Since long-lasting hyperglycemia causes modification of cellular proteins, it is possible that expression of molecular chaperones may be altered during the course of diabetes. Here, we examined the cellular levels of stress proteins such as HSP105, HSP90 and HSC70/HSP70 in various tissues of streptozotocin-induced diabetic rats. In comparison to controls, the levels of HSC70 were markedly decreased in the liver but not in the brain, adrenal gland and pancreas of diabetic rats. The levels of HSP105 and HSP90 were not significantly changed in these tissues of diabetic rats. Furthermore, the induction of HSP70 as well as HSC70 by hyperthermia was significantly reduced in the liver and adrenal gland of diabetic rats. These results suggested that the expression and induction of HSC70/HSP70 may be altered during the course of diabetic disease and may result in impairment of the cytoprotective ability of diabetic rats.

Genetic and epigenetic events in human hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is the most frequently occurring liver carcinoma world-wide. Clinical and molecular medical analyses have produced a considerable amount of information about liver carcinogenesis. Loss of heterozygosity (LOH) analyses have revealed several chromosomal loci harboring potential tumor suppressors. These data support the idea that deletion or inactivation of tumor suppressors including RB, p53, BRCA2, E-cadherin and other candidate genes seem to be common events in HCC development. Factors associated with cell cycle regulation via the Wnt- and MAPK/ERK signaling pathways are frequently deregulated in hepatocarcinogenesis. Aberrant activation of telomerase also occurs in precancerous as well as cancerous lesions in HCC patients. To characterize the wide variety of genetic events that occur in HCC, mRNA expression has been compared in HCC and non-cancerous liver tissues, and several differentially expressed genes have been identified. Hepatitis B and C viruses are the main risk factors for HCC, and indeed some accessory functions of viral products seem to contribute to tumor development; however, whether they have a direct carcinogenic effect has not yet been established.

Enhanced expression of S8, L12, L23a, L27 and L30 ribosomal protein mRNAs in human hepatocellular carcinoma

Differential display (DD) analysis using surgically resected human hepatocellular carcinoma (HCC) and adjacent non-tumorous liver tissues was performed. We identified 5 cDNAs up-regulated in human hepatocellular carcinoma, encoding S8, L12, L23a, L27 and L30 ribosomal protein mRNAs. Northern blot analysis, using total RNAs from thirteen pairs of HCC and abjacent non-tumorous liver tissues demonstrated that these mRNA levels were up-regulated along with the histological grading of tumors. The expression of these mRNAs was also high in three human HCC cell lines (HuH-7, HepG2 and HLF), irrespective of the growth state. These results suggest that activation of these genes is an important manifestation of HCC phenotypes.

Enhanced expression of mRNAs of antisecretory factor-1, gp96, DAD1 and CDC34 in human hepatocellular carcinomas

To identify differentially expressed genes in hepatocarcinogenesis, we performed differential display analysis using surgically resected hepatocellular carcinoma (HCC) and adjacent non-tumorous liver tissues. We identified four cDNA fragments upregulated in HCC samples, encoding antisecretory factor-1 (AF), gp96, DAD1 and CDC34. Northern blot analysis demonstrated that these mRNAs were expressed preferentially in HCCs compared with adjacent non-tumorous liver tissues or normal liver tissues from non-HCC patients. The expression of these mRNAs was increased along with the histological grading of HCC tissues. These mRNA levels were also high in three human HCC cell lines (HuH-7, HepG2 and HLF), irrespective of the growth state. We also demonstrate that sodium butyrate, an inducer of differentiation, downregulated the expression of AF and gp96 mRNAs, supporting in part our pathological observation. Immunohistochemical analysis revealed that gp96 and CDC34 proteins were preferentially accumulated in cytoplasm and nuclei of HCC cells, respectively. Overexpression of these genes could be an important manifestation of HCC phenotypes and should provide clues to understand the molecular basis of hepatocellular carcinogenesis.

Use of serial analysis of gene expression (SAGE) technology

Serial analysis of gene expression, or SAGE, is an experimental technique designed to gain a direct and quantitative measure of gene expression. The SAGE method is based on the isolation of unique sequence tags (9-10 bp in length) from individual mRNAs and concatenation of tags serially into long DNA molecules for a lump-sum sequencing. The SAGE method can be applied to the studies exploring virtually any kinds of biological phenomena in which the changes in cellular transcription are responsible. SAGE is a highly competent technology that can not only give a global gene expression profile of a particular type of cell or tissue, but also help us identify a set of specific genes to the cellular conditions by comparing the profiles constructed for a pair of cells that are kept at different conditions. In this review, we present an outline of the original method, several studies achieved by using the method as a major strategic tool, technological difficulties and intrinsic problems that emerged, and improvements and modifications of the method to cope with these drawbacks. We then present our modified SAGE procedure that generates longer sequence tags (14 bp) rather in detail, and the profile (80K profile) derived from HeLa cells that is composed of 80000 tags obtained from a single library. In addition, a series of smaller profiles (2, 4, 10, 20 and 40K) was made by dividing the 80K profile. When we compared these smaller profiles with respect to tag counts for a number of genes, it became apparent that counts of most gene tags increase stably and constantly as the size of profiles increase, while several genes do not. This may be another problem we have to keep in mind, when the profiles are compared for the identification of 'specific genes'.

Effect of cilnidipine on left ventricular diastolic function in hypertensive patients as assessed by pulsed Doppler echocardiography and pulsed tissue Doppler imaging

The purpose of the present study was to examine the mechanisms of improvement in left ventricular (LV) diastolic function in hypertensive patients treated with cilnidipine, a new and unique calcium antagonist that has both L-type and N-type voltage-dependent calcium channel blocking actions, using pulsed Doppler echocardiography and pulsed tissue Doppler imaging. The study comprised 35 untreated patients with essential hypertension (19 men and 16 women; mean age 65+/-10 years). The peak early diastolic and atrial systolic transmitral flow velocities (E and A, respectively) and their ratio (E/A), and the peak early diastolic and atrial systolic motion velocities (Ew and Aw, respectively) of the LV posterior wall and their ratio (Ew/Aw) were determined in all patients before and after 1, 3 and 6 months on cilnidipine (10 mg/day). One month: Systolic and diastolic blood pressures were significantly decreased. E and E/A were significantly increased, whereas there were no significant changes in Ew and Ew/Aw. Three months: Ew and Ew/Aw were significantly increased compared to those before and 1 month after cilnidipine. Six months: E and E/A were significantly increased compared with before and 3 months after cilnidipine, and Ew and Ew/Aw were significantly increased compared with before cilnidipine. Moreover, the LV mass index was significantly decreased compared to that before cilnidipine. In summary, changes in LV diastolic performance in patients with essential hypertension following cilnidipine treatment were biphasic with an initial increase in early diastolic transmitral flow velocity and a later increase in early diastolic LV wall motion velocity. The initial and later changes can be related to an acute change in afterload and a later improvement in LV relaxation.

Effects of cytochalasin D and latrunculin B on mechanical properties of cells

Actin microfilaments transmit traction and contraction forces generated within a cell to the extracellular matrix during embryonic development, wound healing and cell motility, and to maintain tissue structure and tone. Therefore, the state of the actin cytoskeleton strongly influences the mechanical properties of cells and tissues. Cytochalasin D and Latrunculin are commonly used reagents that, by different mechanisms, alter the state of actin polymerization or the organization of actin filaments. We have investigated the effect of a wide range of Cytochalasin D and Latrunculin B concentrations (from 40 pM to 10 microM) on the mechanical properties of the cells within fibroblast populated collagen matrices. Contractile force and dynamic stiffness were measured by uniaxial stress-strain testing. The range of effective concentrations of Cytochalasin D (200 pM-2 microM) was broader than that of Latrunculin B (20 nM-200 nM). Activating the cells by serum did not change the effective range of Cytochalasin D concentrations but shifted that of Latrunculin B upward by tenfold. Simple mathematical binding models based on the presumed mechanisms of action of Cytochalasin D and Latrunculin B simulated the concentration-dependent mechanical changes reasonably well. This study shows a strong dependence of the mechanical properties of cells and tissues on the organization and degree of polymerization of actin filaments.

Expression of intercellular adhesion molecule-1 induced by high glucose concentrations in human aortic endothelial cells

We examined the effects of high glucose concentrations on the expression of adhesion molecules in human aortic endothelial cells. Expression levels of both mRNA and protein of intercellular adhesion molecule-1 (ICAM-1) were increased after incubation of endothelial cells with 30 mM glucose for 24 h. The effect of glucose on ICAM-1 was concentration dependent, partially attributable to osmolarity, and enhanced by glycated-collagen. Staurosporine (10 nM), epalrestat (10 microM) suppressed the expression of ICAM-1 mRNA and protein induced by high glucose to variable extents. Aminoguanidine (50 mM) suppressed the expression of ICAM-1 protein. It is thought that soluble ICAM-1 protein is produced by shedding in human aortic endothelial cells because RNA for the soluble form of ICAM-1 formed by variant splicing has not been detected. These results show that glucose is an important determinant of ICAM-1 expression in endothelial cells, and suggest that ICAM-1 molecules induced by hyperglycemia may contribute to the development of atherosclerosis in diabetes mellitus.