Blood rheology and the low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio in dyslipidaemic and normolipidaemic subjects

The association between blood rheology and the ratio of low-density lipoprotein cholesterol (LDL-C) to high-density lipoprotein cholesterol (HDL-C) was investigated in 142 dyslipidaemic and 253 normolipidaemic subjects. Blood rheology was examined by the microchannel method and fasting serum concentrations of LDL-C, triglyceride and HDL-C were measured. Passage time of whole blood correlated positively with LDL-C concentration, triglyceride concentration and LDL-C/HDL-C ratio, and negatively with HDL-C concentration. Passage time of whole blood was significantly higher in dyslipidaemic and normolipidaemic subjects with LDL-C/HDL-C ratio > 2.0 than in those with ratio < 1.5. Thus, dyslipidaemic subjects had impaired blood rheology, elevated LDL-C and triglyceride concentrations and elevated LDL-C/HDL-C ratio, and reduced HDL-C concentrations. Dyslipidaemic and normolipidaemic subjects with a more elevated LDL-C/HDL-C ratio had greater blood rheology impairment than those with a less elevated ratio. These data suggest that an elevated LDL-C/HDL-C ratio may be helpful in predicting impaired blood rheology.

Influence of thyroid hormones and transforming growth factor-β1 on cystatin C concentrations

Serum cystatin C concentrations are reported to increase in the hyperthyroid state. Serum concentrations of cystatin C and transforming growth factor-β1 (TGF-β1) were measured in patients with thyroid dysfunction, and the effects of 3,5,3'-tri-iodothyronine (T(3)) and TGF-β1 on cystatin C production in human hepatoblastoma (Hep G2) cells were studied. Serum concentrations of cystatin C and TGF-β1 were significantly higher in patients with Graves' disease compared with control subjects. Significantly positive correlations were observed between thyroid hormones and cystatin C, thyroid hormones and TGF-β1, and TGF-β1 and cystatin C in patients with thyroid dysfunction. Serum concentrations of cystatin C and TGF-β1 decreased after treatment for hyperthyroidism. Cystatin C mRNA levels and cystatin C secretion were increased by T(3) and TGF-β1 in cultured Hep G2 cells. These results suggest that serum cystatin C concentrations increase in patients with hyperthyroidism. The mechanisms for this may involve elevation of serum TGF-β1 levels and the stimulatory effects of T(3) and TGF-β1 on cystatin C production.

Clinical features associated with circulating concentration of soluble leptin receptor in patients with diabetes

We aimed to determine if there were any clinical features that were significantly associated with the circulating concentration of soluble leptin receptor (OB-Re) in 67 Japanese subjects with diabetes mellitus. The characteristics evaluated included age, height, body weight, body mass index (BMI), systolic and diastolic blood pressure, duration of diabetes, haemoglobin A1C and blood lipid concentrations, urinary albumin excretion rate, circulating concentrations of leptin, tumour necrosis factor-alpha (TNF-alpha), TNF-alpha receptor 1 and genotypes of the angiotensin-converting enzyme (ACE) gene. We found statistically significant negative correlations between circulating OB-Re concentration and body weight, BMI, diastolic blood pressure, concentrations of leptin and TNF-alpha receptor 1. Serum OB-Re concentration was not associated with any of the other clinical characteristics that were measured, or with the different ACE genotypes. Our results suggest that OB-Re might have an important influence on the biological activity of leptin in diabetic subjects.

Congestive heart failure induced by the combination of atrial fibrillation and tricuspid regurgitation

Atrial fibrillation (AF) and tricuspid regurgitation (TR) may induce congestive heart failure (CHD). Using electrocardiography and echocardiography, we examined the clinical characteristics and haemodynamic findings in 100 patients with AF + TR + CHF, AF + TR, AF or TR. The fractional shortening in all groups with AF was significantly decreased compared with the TR group. The ejection fraction in patients with AF + TR + CHF was significantly lower than in the TR group. Twenty-four of the 72 patients with AF and TR (with or without CHF) were treated, and 13 were monitored for heart rate and severity of TR. Eight months after start of treatment the heart rate and typical symptoms and signs of heart failure had improved significantly in nine patients, but the severity of TR did not change. TR worsened in the remaining four patients but they did not develop CHF. Our results suggest that increased heart rate due to the combination of AF and TR could be responsible for CHF.

Inflammatory cytokines in vitreous fluid and serum of patients with diabetic vitreoretinopathy

To determine whether inflammatory cytokines are increased in proliferative diabetic retinopathy. We measured concentrations of interleukin-6, 8 (IL-6, 8) and tumor necrosis factor (TNF)-alpha by enzyme-linked immunosorbent assay (ELISA) in vitreous and serum from 47 patients with proliferative diabetic retinopathy and 21 patients with vitreous noninflammatory retinopathies. Vitreous concentration of IL-6 were 64.7+/-12.8 pg/ml in proliferative diabetic retinopathy, much greater (P<.005) than in noninflammatory retinopathy (2.8+/-4.5 pg/ml). Amounts of IL-8 in vitreous fluid also were greater in proliferative retinopathy than in noninflammatory retinopathy (34.0+/-11.5 vs. 6.1+/-2.0 pg/ml, P<.005). Concentrations of TNF-alpha in vitreous fluid were not statistically different in proliferative retinopathy from those in noninflammatory retinopathy. In sera, concentrations of IL-6 and IL-8 were not different between proliferative and noninflammatory retinopathy. However, serum TNF-alpha was much greater in proliferative retinopathy than in noninflammatory retinopathy (0.81+/-0.72 vs. 0.09+/-0.00 pg/ml, P<.001). Elevated TNF-alpha in serum then may be diagnostically useful in proliferative diabetic retinopathy. And inflammatory cytokines in vitreous may be pathogenically important in this concentration.

Correlation of circulating interleukin-10 with thyroid hormone in acute myocardial infarction

In patients with acute myocardial infarction (AMI), euthyroid sick syndrome (ESS) has been reported to be linked to increase in interleukin (IL)-6 and activation of its receptors. Recent reports have shown that IL-10, an anti-inflammatory cytokine, also plays a key role in the pathogenesis of AMI. Therefore we investigated the relationship between thyroid state and IL-10 in patients with AMI. We measured thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4), IL-10, and IL-6 in plasma from 20 patients with AMI and 20 healthy controls. All 20 AMI patients showed significantly lower concentrations of FT3 than in controls accompanied by normal or subnormal levels of TSH, characterized ESS. Concentrations of IL- 10 and IL-6 were higher in patients than in controls. Both IL-10 and IL-6 significantly (p<0.05, respectively) correlated with thyroid hormone in patients with AMI. Time course of IL-10, IL-6, and FT3 seemed to be tightly linking. In conclusion, IL-10 and IL-6 appears to affect thyroid hormone homeostasis in patients with AMI.

Type IV collagen serum and vitreous fluid levels in patients with diabetic retinopathy

We compared the levels of type IV collagen (IV-C) in vitreous fluid and serum and the levels of glycosylated haemoglobin in 47 patients with proliferative diabetic retinopathy (DR) and 21 patients with non-inflammatory retinopathies. Levels of IV-C were found to be higher in the vitreous fluid in patients with DR than in patients with non-inflammatory retinopathy (53.2 +/- 14.9 microg/l versus 14.7 +/- 4.5 microg/l). Serum levels were likewise higher in patients with DR (349.7 +/- 106.2 microg/l versus 97.7 +/- 13.1 microg/l) as were glycosylated haemoglobin levels (8.3 +/- 0.3% versus 5.2 +/- 0.4%). In addition, levels of type IV collagen in the vitreous fluid were found to be higher in the patients who had been diabetic for > or = 10 years than in patients who had been diabetic for < 10 years (54.8 +/- 15.5 microg/l versus 16.8 +/- 4.6 microg/l). We conclude that accumulation of vitreous fluid IV-C may relate to high levels of glycosylated haemoglobin and long duration of diabetes. This suggests that the concentration of IV-C in vitreous fluid, and possibly also the serum levels of IV-C, reflects the progression of DR. Further investigation is needed to verify this and to investigate whether or not measuring IV-C levels is a useful means to assess therapeutic effects and/or prognosis of diabetic microangiopathy.

Evaluation of signal-averaged electrocardiography for clinical diagnosis in arrhythmogenic right ventricular dysplasia

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown etiology that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. We investigated the relationship between the electrocardiogram (ECG) appearances and signal-averaged ECG (SAECG) in 7 cases with ARVD, and evaluated the usefulness of SAECG as a screening test to detect patients with ARVD. Compared with the conventional 12-lead ECG, the SAECG detects abnormalities at a higher rate in ARVD patients (57% versus 86%). SAECG was more sensitive as a screening test to detect patients with ARVD than 12-lead ECG.

Circulating interleukin-6 and interleukin-6 receptors in patients with acute and recent myocardial infarction

Interleukin-6 (IL-6), a proinflammatory cytokine, plays a key role in the pathogenesis of coronary artery disease (CAD). We investigated circulating IL-6 and its receptors in patients with CAD. We evaluated 39 Japanese patients with CAD (30 males and 9 females aged 36-79 years), measuring their plasma levels of IL-6 and IL-6 receptors alpha and beta (IL-6R alpha, IL-6R beta). Circulating levels of IL-6, IL-6R alpha and IL-6R beta were measured by an enzyme-linked immunosorbent assay. Blood was sampled immediately after admission and again after 1, 2, 3, 6 and 9 h, then every 12 h for 5 days. Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) were measured on day 3 after symptom onset. Plasma levels of IL-6 and IL-6Rs were significantly increased in 28 patients with acute myocardial infarction (AMI) compared with 15 normal controls. However, neither IL-6 nor IL-6Rs showed an increase in 6 patients with angina pectoris. We observed two peaks for circulating IL-6 in AMI, the first of which showed a significant correlation with ANP as well as BNP. These results may help to explain why the amount of IL-6 produced is closely related to the severity of myocardial dysfunction in patients with CAD.

Circulating interleukin-6 significantly correlates to thyroid hormone in acute myocardial infarction but not in chronic heart failure

To investigate relationships between thyroid states and the cardiac endocrine system, we analyzed thyrotropin (TSH), thyroid hormone, plasma levels of interleukin-6 (IL-6) and brain natriuretic peptide (BNP) in 50 patients with chronic heart failure (CHF), in 30 patients with heart failure from acute myocardial infarction (AMI), and in 15 controls. Plasma levels of IL-6 and BNP in both CHF and AMI were significantly elevated, while free triiodothyronine (FT3) was significantly decreased compared to controls. FT3/free thyroxine (FT4) ratio was significantly decreased in CHF but not in AMI compared to controls. In CHF, diuretic treatment diminished circulating BNP but not IL-6, while diuretic treatment increased FT3/FT4 ratio. In AMI, FT3/FT4 ratio was significantly decreased 72 h compared to 12 h after the onset of AMI, while BNP and IL-6 were significantly increased 72 h compared to 12 h after the onset of AMI. In both CHF and AMI, BNP significantly correlated with FT4. On the other hand, significant correlations between IL-6 and FT3, and between IL-6 and FT3/FT4 ratio were detected in AMI but not in CHF. This preliminary study suggests that IL-6, BNP and thyroid hormone reflect ventricular dysfunction in both acute and chronic heart failure, and that IL-6 significantly relates to circulating thyroid hormone in AMI but not in CHF.

Involvement of circulating interleukin-6 and its receptor in the development of euthyroid sick syndrome in patients with acute myocardial infarction

OBJECTIVE

In patients with acute myocardial infarction (AMI), low triiodothyronine (T(3)) levels with normal or subnormal levels of thyrotropin (TSH), the euthyroid sick syndrome (ESS), have been reported, however, the mechanism of altered thyroid hormone metabolism is unknown. Recent reports have shown that interleukin-6 (IL-6) plays a key role in the pathogenesis of AMI and ESS. This preliminary study investigates the relationship between thyroid states and plasma levels of IL-6, the soluble IL-6 receptor (sIL-6R), and the soluble transducing 130kDa glycoprotein (sgp130) in AMI.

DESIGN AND METHODS

We measured the concentration of TSH, free T(3) (FT(3)), free thyroxine (FT(4)), IL-6, sIL-6R and sgp130 in plasma from 24 patients with AMI and 20 normal controls.

RESULTS

All 24 AMI patients showed significantly lower concentrations of FT(3) with normal or subnormal levels of TSH, and higher concentrations of IL-6 and sIL-6R than controls. IL-6 level was correlated with creatine phosphokinase (CPK) and FT(3) levels but not with FT(4 )or TSH levels in patients with AMI. The time course of IL-6 and FT(3 )concentration seemed to be closely linked. sIL-6R level was correlated with CPK and sgp130 levels, but not with FT(3), FT(4) or TSH levels. FT(4 )level was correlated with sgp130 level.

CONCLUSION

Patients with AMI develop ESS through activation of IL-6 and its receptor system.

Prolongation of QT interval and ventricular septal hypertrophy

Long QT syndrome (LQTS) is a prime example of interplay between molecular biology, cellular physiology, and organ physiology. Both the congenital and acquired forms of LQTS are due to intrinsic and/or acquired abnormalities of the ionic currents responsible for cardiac repolarization. We analyzed the QTc interval, QRS axes and interventricular septal thickness (IVST) in 41 patients who had a prolonged QT interval on routine electrocardiography (ECG) (5 females and 36 males, mean age 65+/-13 years). The QRS axis of patients in the LQTS group (27+/-49 degrees) was significantly lower (p < 0.05) than in the control group (46+/-26 degrees). However, the IVST in the LQTS group (10+/-2 mm) was significantly thicker than in the control group (9+/-1 mm) (p < 0.05), while the WTd was not significantly different. The QTc interval in patients with ventricular septal hypertrophy (IVST > or = 12 min, 478.8+/-7.9 msec) was significantly longer (p < 0.05) than in the normal group (IVST < 12 mm, 472.1+/-17.5 msec). In conclusion, the results of this preliminary study suggest that prolongation of the QT interval on ECG should prompt screening for electrocardiographic evidence of ventricular hypertrophy in patients with this disease.

[Studies on circulating interleukin-6 and thyroid functions in acute myocardial infarction]

The euthyroid sick syndrome is reported to exist in acute myocardial infarction(AMI). Previous reports showed serum levels of triiodothyronine(T3) are low and thyroid stimulating hormone(TSH) is normal or subnormal levels in patients with AMI. However, the mechanism of altered thyroid hormone metabolism is unknown. Interleukin-6(IL-6) is reported to be a key role in the pathogenesis of AMI and euthyroid sick syndrome. We measured circulating TSH, free T3(FT3), free thyroxine (FT4), IL-6, soluble IL-6 receptor, soluble transducing 130-kD glycoprotein, atrial natriuretic peptide(ANP) and brain natriuretic peptide in 25 patients and 32 healthy subjects. Circulating FT3 levels in patients with AMI became lower than in control group(p < 0.05). IL-6 levels were significantly(p < 0.05) higher than those of healthy subjects. The peak levels of IL-6 was 30.5 +/- 46.9 pg/ml at 25-27 hours(the first peak) and 64.4 +/- 24.6 pg/ml at 70-72 hours(the second peak). FT3 was negatively related to IL-6(p < 0.05) and hANP(p < 0.05) in patients with AMI. These results indicate that the lower levels of FT3 show the greater severity of AMI. We conclude that euthyroid sick syndrome occurs in patients with AMI and euthyroid sick syndrome may regulated by IL-6 through suppressed of thyroid function.

Type IV collagen as an early marker for diabetic nephropathy in non-insulin-dependent diabetes mellitus

We measured urinary albumin (U-Alb) and type IV collagen (uIV.C) in spot urine collected from 82 patients with non-insulin-dependent diabetes mellitus (NIDDM) and 205 controls. Eighty-two NIDDM patients that had no increased excretion of either U-Alb or uIV.C were observed for 6 months. Prevalence of increased excretion of U-Alb and uIV.C at 6 months in these patients were 32.9%, and 62.2%, respectively. Increased excretion of uIV.C was detected in 27 patients without microalbuminuria. chi(2) analysis suggested that uIV.C was more sensitive than U-Alb, and that hypertension enhanced increased excretion of both U-Alb and uIV.C. uIV.C was significantly correlated (P<0.01) with U-Alb but not glycosylated hemoglobin A1C (HbA1C) in NIDDM patients. Taken together, uIV.C may be a useful marker for early diabetic nephropathy.

Serum thrombomodulin as a prognostic marker of disseminated intravascular coagulation

Disseminated intra-vascular coagulation (DIC) is associated with severe bleeding tendency and organ failure, the extent of which is thought to be related to the prognosis of DIC patients. Thrombomodulin (TM) is a high-affinity thrombin receptor on vascular endothelial cells. Clinical importance of soluble TM is still controversy as a diagnostic and prognostic indicator in patients with disseminated intravascular coagulation (DIC). We compared plasma levels of TM with fibrin degradation product (FDP) in patients with DIC through the clinical course. The significant elevation of circulating TM in nonsurvivors with DIC compared with survived patients with DIC(TM 3.1+/-1.52 vs 8.1+/-3.89 FU/ml), as well as FDP (12.9+/-12.12 vs 49.8+/-55.42 microg/ml) but the levels of FDP were not different between the two groups. The measurement of circulating TM was a relatively good prognostic marker of patients with DIC.

[Congestive heart failure due to a combination of atrial fibrillation and tricuspid regurgitation: clinical course and echocardiographical analysis]

The combination of atrial fibrillation (Af) and tricuspid regurgitation (TR) may induce the congestive heart failure (HF) due to insufficient output. However, these associations have not been elucidated. We examined the clinical course with echocardiographic data in 119 patients with Af and/or TR and/or HF. Their mean age was 65 +/- 14 years. The patients were classified into 6 groups as follows: Group I contained patients with Af, TR and HF(n = 13); Group II contained patients with Af and TR, without HF(n = 59); Group III contained patients with TR and HF, without Af(n = 15); Group IV contained patients with TR and without AF and HF(n = 15); Group V contained patients with Af and HF, without TR(n = 24); Group VI contained patients with Af and without TR and HF(n = 13). The fractional shortening and ejection fraction in Group I and II were significantly (p < 0.05) decreased compared to Group IV. Moreover, the fractional shortening in Group V was significantly (p < 0.05) lower than in Group IV. Among 72 cases in Group I and II, 24 cases were followed by echocardiography for 2 to 5 years. Eight cases of HF exhibited a no HF state and 1 demonstrated had the HF state. All 9 cases (38%) showed a decreased heart rate and no alternation of TR. Four of the 24 patients (17%) had developed worsened TR and a lowered ejection fraction but none developed them became HF. Therefore, tachycardia may be an accelerative factor for HF due to the combination of Af and TR, not due to the grade of TR.

[The significance of determination of urinary type IV collagen concentrations from a random urine collection in patients with non-insulin dependent diabetes mellitus]

Recently, we have developed a highly sensitive assay system for quantitative measurement of urinary type IV collagen. To obtain a basic evaluation of the assay system we used urine specimens, collected randomly and studied the relation to diabetic nephropathy in patients with non-insulin dependent diabetes mellitus (NIDDM). It was shown that this assay system could measure the samples without concentrating the urine. Urinary sediments which were reported to interfere with the assay could be removed by adding Tris-buffer. In the clinical studies, urinary type IV collagen concentrations were significantly higher in patients with NIDDM regardless of the presence or the absence of albumin. Cases with abnormal values of urinary type IV collagen in the normal albuminuria group were 41.6%, while those with abnormal values of urinary transferrin excretion were 31.0%. Furthermore, among the normal albuminuria group, glycosylated hemoglobin (HbA1c) levels were higher in the groups of abnormal values of urinary type IV collagen than those within the reference values. These results obtained herein suggest that urinary type IV collagen could be a useful marker for the early stage of diabetic nephropathy.