[Dirofilariasis in the Nizhny Novgorod Region].

The paper presents the results of clinical, epidemiological, and epizootological analyses of local cases of human dirofilariasis in the Nizhny Novgorod Region, which suggest that natural and climatic changes, namely the abnormally hot summer in 2010-2011 and increasing migratory processes among human beings and animals, open up possibilities for forming foci ofdirofilariasis outside habitats of Dirofilaria repens.

[Electrogastrography in diagnosis of ulcerative pyloroduodenal stenosis].

Skin electrogastrogram was made in 40 healthy controls and 32 patients with ulcerative pyloroduodenal stenosis in fasting condition and after mixed meal. Fasting frequency of gastric bioelectric activity (BA) was similar in the patients and the controls (2.65 +/- 0.

[The blocking action of platelet-activating factor (PAF) on the calcium currents of the atrial fibers in the frog and guinea pig].

The effects of platelet-activating factor (PAF) on the myocardial cell membrane Ca-current (ICa) and Ca-action potential (Ca-AP) were investigated. In double sucrose-gap voltage-clamped frog atrial trabeculae PAF (2 X 10(-7) M) reduced ICa-amplitude to 40-50%; at the same time the IK-amplitude was increased to the same value. These changes of ICa and IK amplitudes were protected by simultaneous action of PAF and PAF antagonist BN 52021 (4 X 10(-6) M).

[Interactions of PAF and its antagonists in the guinea pig atrial myocardium].

The effects of platelet activating factor (PAF) and three its antagonists on the transmembrane intracellular potentials and stimulated (0.5 Hz) contraction amplitude (CA) of the left auricle has been studied. PAF (1-5 X 10(-7) M) was added to the standard Tyrode solution or the same perfusing solution with 15 mM K+, and 6 mM Ca++ (t = 30 degrees C, pH = 7,2).

[Cardiodepressive effect of platelet activating factor].

The cardiodepressive effect of PAF has been studied on the electrical and mechanical activities of isolated auricles of guinea pig. Intracellular resting potential, action potential (AP) and isometric contractions elicited by electrical stimulation (0.5 Hz) were measured.

[Cardiodepressive effect of blood serum in severe forms of purulent infection].

The effect of human blood serum from patients with purulent infections (sepsis, purulent resorptive fever) has been studied on the electrical and mechanical activities of isolated auricles of guinea pig. The intracellular resting potentials (RP), action potentials (AP) and isometric contractions elicited by electrical stimulation (1 Hz) were measured. The patient serum diluted by Tyrode solution (1:1) didn't change RP values and AP amplitude but caused a decrease in the AP plateau phase duration (P less than less than 0.

[Intensification of human myocardial contractile activity as affected by blood serum].

The effect of human serum diluted in Tyrode solution (1:1) on the cardiac contractility has been studied. Fragments of the right auricle myocardium from patients with congenital and acquired heart disease have been used to study serum effect on the contraction force. Myocardial strips were repeatedly stimulated with electrical impulses at a frequency of 0.

[Method for isolating single cardiac cells in the guinea pig using pronase. The role of calcium ions].

A method for isolation of guinea-pig cardiomyocytes with pronase has been developed. The method has been assessed in hearts perfused with solutions containing pronase (1 U/ml) and 200 microM Ca2+. Eighty per cent of the cells released were rod-shaped and 1.

[Effect of staphylococcal toxin and antistaphylococcal gamma-globulin on the electrical and contractile activity of the guinea pig myocardium].

A study was made of the action of staphylococcal toxin (ST) and its combination with antistaphylococcal gamma-globulin (ASGG) on intracellular potentials (rest potential--RP, and action potential--AP), and isometric contractions of guinea-pig auricle. ST (initial concentration 18.10(-2)Lh) diluted with normal Tyrode's solution at 1:1000, 1:100 and 1:10 (spontaneously active preparations), and Tyrode's solution with 13.

[Relationship between the oscillatory contractions and myocardial tonus in patients with heart defects].

Interplay between contraction oscillations and the tone that is seen during rhythmic stimulation was studied in atrial trabeculae of patients with heart diseases. It was disclosed that in 50% of myocardial preparations from patients with rheumatic heart diseases, an increase in the tone (incomplete relaxation) and oscillations appeared at a frequency of 0.2 HZ.

[Effect of cooling on rhythmo-inotropic relations in pathologically altered myocardium].

Fragments of the right atrium auricle from patients with congenital and acquired heart diseases were used to study the effect of the Tyrode solution temperature over the 60-minute cessation of electrical stimulation of the preparations on the recovery of the amplitude of rhythmic contractions after the pause. The lack of stimulation within 34 to 24 degrees C does not lower the contraction amplitude after warming of the preparations and renewal of rhythmic stimulation. The hypothermal pause at a temperature of 10-14 degrees C leads to the development of contractures and suppresses the myocardial contractility.

[Analysis of the changes in duration of the action potentials of the myocardial cells of guinea pigs in local anaphylactic reaction and the effect of histamine].

The relationship between the frequency of the spontaneous activity and the action potential duration (APD) has been studied on the right cardiac auricular appendage of guinea pigs during cardiac anaphylaxis (ovalbumine was used as an antigen, 2.10(-4)--2.10(-5 g/ml) and histamine action (1.

[Mechanism of excitation and contraction uncoupling in frog and guinea pig myocardial fibers during block of slow sodium-calcium channels by compound D-600].

In the experiments performed on the strips of frog's atria and ventricle it was found that rhythmic stimulation facilitated the dissociation of excitation--contraction coupling caused by D-600 compound through the block of calcium channels, i.e. D-600 prevented the increase of tension in the series of contractions or even converted positive staircase into negative one.

[Changes in the electric activity of the myocardial fibers of the guinea pig during local anaphylactic reactions under conditions of inactivation of "rapid" sodium channels].

Changes of electrical activity (intracellular records) of guinea pig heart auriculus were studied during experimental cardiac anaphylaxis (ovalbumine being used as an antigen). Fast Na channels of the myocardial fibers having been depressed by long-standing depolarization in K+-rich (20 mM) Tyrode solutions, only the low-amplitude slow responses to brief stimuli were recorded. Addition of ovalbumine (2.

Possible role of slow sodium-calcium channels in the mechanism of changes in electrical and mechanical activity of guinea pig heart cells in local anaphylaxis (the isoptine effects).

The local anaphylactic reaction and the effects of histamine during blocking of the slow sodium-calcium channels by isoptine were investigated in the spontaneously contracting oracle of the atrium of a guinea pig previously sensitized to egg albumin. Simultaneously with the intracellular recording of the potentials, isometric contractions of the preparation were recorded by means of a mechanotron. The investigation showed that egg albumin (0.