The detection of early myocardial changes in asymptomatic diabetic individuals by 99mTc - Myoview gated-SPET and heart rate variability measurement.

AIMS: Incidence of early myocardial changes in asymptomatic diabetic individuals is not clearly documented. In the present study, we examined diabetic patients without a history of cardiovascular disease with negative treadmill test and no signs of systolic dysfunction for presence of cardiac autonomic neuropathy established by measurement of heart rate variability (HRV) and (99m)Tc - Myoview gated-SPET. MATERIALS AND METHODS: 47 type I and type II diabetic patients were subjected to prospective study including echocardiography and HRV measurement using the combination of Ewing´s testing and spectral analysis. Subsequently, patients underwent treadmill test and stress myocardial perfusion scintigraphy. Additionally, vascular and metabolic parameters were collected. RESULTS: Treadmill test was negative in all patients. Diastolic dysfunction was found in 10 % of T1DM and 11 % of T2DM patients by echocardiography, whereas none of the patients had systolic dysfunction. SPET confirmed hypoperfusion in 35 % T1DM (p=0.01) and in 60 % T2DM (p=0.001). Diagnosis of cardiac autonomic neuropathy based on Ewing´s testing and HRV examination was established in 60 % of T1DM patients (p=0.001) and 77 % of T2DM patients (p=0.001). In T1DM group, significant association was found between cardiac autonomic neuropathy (CAN) and frequency of hypoglycaemia (p=0.04). No such correlations were found in patients with T2DM. CONCLUSION: The results of the present study show high incidence of myocardial hypoperfusion and cardiac autonomic neuropathy among asymptomatic diabetic patients, whereas the standard diagnostic approaches including treadmill test and echocardiography failed to show any changes. Therefore, we conclude that diabetic heart disease remains underdiagnosed by standard approaches, but could be detected in asymptomatic patients by more sensitive methods, such as HRV measurement and myocardial scintigraphy (Tab. 2, Fig. 2, Ref. 26).

[Adrenomyeloneuropathy as the cause of Addison's disease]. / Adrenomyeloneuropatia ako prícina Addisonovej choroby.

The authors describe adrenoleukodystrophy and adrenomyeloneuropathy found in one family. This disease is a less frequent cause of Addison's disease, but it is very serious from the prognostic aspect. The authors recommend therefore to examine very long chain fatty acid plasma levels in patients with adrenal insufficiency.

Endogenous digoxin-like immunoactivity and diabetes mellitus: facts and hypotheses.

Substances with digoxin- and ouabain-like immunoactivity (DLIA) are specific inhibitors of Na(+)-K(+)-ATPase which increase the total amount of intracellular stored calcium (Ca2+i). In diabetic patients, DLIA levels have been reported to be increased. Although this increase is probably secondary to sodium retention and volume expansion (included in diabetic subjects by hyperinsulinemia and/or diabetic nephropathy), the question arises of whether it has pathophysiological consequences: namely, whether substances with DLIA, via their effect on Na(+)-K(+)-ATPase activity and Ca2+i stores, could in diabetic subjects facilitate development of hypertension and/or modulate insulin sensitivity or insulin secretion. Clinical findings of correlations of DLIA to blood pressure, insulin levels and to degree of insulin resistance, together with experimental findings of decreased Na(+)-K(+)-ATPase activity, increased Ca2+i and decreased Mg2+i in both diabetic and hypertensive subjects, support these hypotheses. However, the issue of whether or not these relations are causative and whether or not defects in intracellular milieu are primary or secondary to non-insulin-dependent diabetes mellitus has not been resolved yet. Moreover, pathogenesis of both diabetes mellitus and hypertension is multifactorial and includes many other factors. Therefore, further efforts should be made to elucidate the exact role of substances with DLIA in diabetes mellitus.

[Hemostasis in patients with diabetes mellitus. II. Tissue factor and the extrinsic blood coagulation inhibitor]. / Hemostáza u chorých s diabetes mellitus. II. Tkanivový faktor a inhibítor vonkajsieho systému koagulácie.

In the submitted pilot study we examined 37 patients suffering from diabetes mellitus without vascular complications and 15 healthy blood donors. The diabetic patients had not, as compared with the blood donors, significantly elevated values of the tissue factor (TF) and tissue factor pathway inhibitor (TFPI). The TFPI levels correlated with other markers of endothelial dysfunction, in particular thrombomodulin (r = 0.452, p < 0.01) and with triacylglycerol and cholesterol levels. They did not correlate with age, the C-peptide level and BMI.

[Insulin resistance and pathogenesis of non-insulin-dependent diabetes mellitus (I)]. / Inzulínová rezistencia a patogenéza non-inzulín-dependentného diabetes mellitus (I. cast').

The authors present a review of current knowledge of insulin mechanism on cellular level and of the defects leading to diminished cellular insulin sensitivity and to development of insulin resistance (IR). Attention is focused primarily on IR in subjects with non-insulin dependent diabetes mellitus (NIDDM) with main stress on the postreceptor level of insulin effect which includes glucose transport, storage (glycogen-synthesis) and glycolysis. The defects of these mechanisms (namely the decrease in glycogen-synthase activity) are considered the main causes of IR in patients with NIDDM. Beside the above mentioned factors the authors discuss some of the less well-known mechanisms that can be found in the background of IR in patients with NIDDM (tissue blood flow, capillary density, transport of insulin across the endothelial barrier, glucose toxicity, role of intracellular calcium and others.

[Renal excretion of calcium in healthy persons]. / Vylucovanie vápnika oblickami u zdravých jednotlivcov.

The authors examined the calcium excretion in a group of 100 healthy subjects (50 men and 50 women) aged 21-40 years. Urine was collected under ambulatory conditions. Calcium excretion was expressed as Ca excretion per minute, Nordin's index, calciuria/GF.1.73 m2 and the renal threshold for calcium. Calcium excretion per minute was significantly lower in women, as compared with men. This significant difference of mean values of calcium excretion per minute persists when the subjects are classified by sex and age groups. Women aged 31-40 years had a significantly lower calciuria/GF.1.73 m2 than men aged 21-30 years and a significantly higher renal threshold for calcium, as compared with men of equal age. If standard conditions of urine collection are respected, the mentioned examination method can be used during ambulatory examinations of patients with impaired calcium and phosphate metabolism. The assessed values of different indicators must be, however, compared with values of healthy subjects of the same age and sex.

[Relation between morphometric indicators in axons of myelinated peripheral nerve fibers and the age of experimental animals]. / Závislost' morfometrických ukazovatel'ov axónov myelinizovaných nervových vlákien periférneho nervu od veku pokusných zvierat.

The authors observed the dependence of morphometric indicators of myelinated nerve fibers on the age of experimental animals. They performed a morphometric analysis of myelinated nerve fibers, namely nervous peroneus communis in male adult white rats of 17, 21, 25 and 31 weeks of age. They discovered that the values of individual morphometric indicators of axons of myelinated nerve fibers (axon perimeter, axon circular diameter, axon area, circular axon area) and their distribution vary in dependence on age of experimental animals. The authors emphasize that observation of experimental alterations of morphometric indicators of myelinated nerve fiber axons requires a comparison of findings in groups of animals with those in control groups of animals of the same age. (Tab. 2, Fig. 4, Ref. 28.)

[Dynamics of digoxin-like immunoactivity during the oral glucose tolerance test in pregnant women]. / Dynamika digoxínu podobnej imunoaktivity pocas OGTT u tehotných zien.

The changes of serum digoxin-like immunoactivity (DLIA) during 75g oral glucose tolerance test (OGTT), were investigated in 25 pregnant women with various glucose tolerance. 13 women had a normal glucose tolerance (NGT), 12 women had an impaired glucose tolerance (IGT) or gestational diabetes mellitus (GDM). Test was performed after 25 week of pregnancy. The results were compared with 9 nonpregnant healthy volunteers (NHV). After an oral glucose challenge, there was observed a significant decrease in serum DLIA (p < 0.01 in 1st hour), in both groups of the pregnant women. In the group of NHV these findings were not found. Our findings suggest a possible relationships between DLIA and glucose tolerance in pregnant women. However, it needs further investigation. (Tab. 1, Fig. 1, Ref. 24.)

[Endogenous digitalis-like substance in relation to glycemia and insulinemia]. / Endogénna substancia podobná digitálisu vo vzt'ahu ku glykémii a inzulinémii.

The digitalis-like substance (DLS), insulin resistance, and hyperglycemia are ascribed important roles in the pathogenesis of essential hypertension. The relationship between DLS and glycemia (insulinemia) was investigated in the present study. The levels of glycemia, insulinemia and DLS were measured during oral glucose load in a group of 18 subjects with various blood pressure values. Fasting levels of glycemia and insulinemia were in each subject within the physiological range and no correlation was found to exist between the fasting levels of DLS and glycemia (insulinemia). One hour after oral glucose load the increase of glycemia and insulinemia was significantly higher in the group of subjects with SBP > 140 and/or DBP > 90 mmHg than in normotensive subjects (p < 0.001). The increase in glycemia (insulinemia) was followed by a decrease of DLS. This contrary trend could be expressed as a significant inverse correlation between the change in plasma DLS and the change in glycemia (r = -0.660 p = 0.0039), and also between the change in plasma DLS and the change insulinemia (r = -0.687 p = 0.0023). These findings are assumed to suggest certain mechanisms involved in the pathophysiology of essential hypertension. (Tab. 3, Fig. 2, Ref. 20.)

[Review of the morphological changes in peripheral nerves in experimental diabetes mellitus]. / Prehl'ad morfologických zmien periférnych nervov pri experimentálnom diabetes mellitus.

A survey of morphological changes of myelinated nerve fibers of peripheral nerves recorded in experimental streptozotocin induced diabetes mellitus in rats is presented. Causes of discordant interpretations of findings are considered and pathogenetic mechanisms involved in morphological changes of myelinated nerve fibers of peripheral nerves observed in this model of diabetes mellitus are discussed. (Ref. 41.)