Electrophysiological characteristics of a population of mushroom body neurons in Apis Mellifera honeybees in kynurenine deficiency.

Electrophysiological methods were used to study the neurophysiological characteristics of mushroom body neurons in snow (laranja) mutant and wild-type bees. The snow (laranja) mutation, which produces a sharp reduction in the activity of the enzyme tryptophan oxygenase, thus creating a deficiency of all kynurenines in the body, modifies the bioelectrical properties of mushroom body neurons. The parameters most dependent on the snow (laranja) mutation and, thus, the level of endogenous kynurenines, were the duration of action potential afterdepolarization recorded from neurons in the calyx and the amplitude of the postsynaptic potential of neurons in the calyx evoked by focal stimulation of the antennal lobes. There was also a tendency to an increase in the spontaneous spike frequency. These data lead to the conclusion that the effect of the mutation is recessive in nature and appears only in homozygotes (bearing two mutant alleles).

Characteristics of neuron activity in the honey bee (Apis mellifera L.) in conditions of kynurenine deficiency.

Neuron activity was studied electrophysiologically in the antennal lobes, mushroom bodies, and cervical connective during ontogenesis (days 1, 3, 7, and 25) in snow(laranija) mutant bees, which suffer kynurenine deficiency, and in wild-type bees. Neuron activity recorded from the cervical connective was found to show the greatest dependence on kynurenine content. Mutation in the structural gene for tryptophan oxygenase, the first and key enzyme in the kynurenine pathway for tryptophan metabolism (KPTM) and which leads to kynurenine deficiency, decreased the frequency of neuron spike activity recorded from the cervical connective. This would appear to be associated with a possible deficiency of glutamic acid; it was independent of the deficiency of kynurenic acid and kynurenine, a point subject to further studies. Clear manifestation of the effect of the mutation requires the presence of two mutant alleles in the bee genome (homozygosity). The effect of the mutation, to inhibit neuron activity in the cerebral ganglion, corresponds to the effect seen previously at the behavioral level. Less clear effects were obtained from recordings of neuron activity from the antennal lobes and mushroom bodies. This may be associated with the complexity of the spectrum of biochemical lesions in different parts of the brain resulting from the mutation.

[Electrophysiological characteristics of a population of mushroom body neurons in Apis mellifera L. honey bee under conditions of kynurenines deficit].

Neurophysiological characteristics of mushroom body neurons were examined by electrophysiological methods in mutants snow(laranja) and wild-type honey bees. Mutation snow(laranja) causes a drastic decrease in the activity of enzyme tryptophane oxygenase that results in deficiency of all kynurenines. It also modifies bioelectrical properties of neurons in the mushroom bodies. The duration of afterdepolarization in spikes recorded from calyx neurons and the amplitude of postsynaptic potentials in these neurons evoked by focal stimulation of antennal lobes were shown to be most dependent on the mutation and, consequently, on the content of endogenous kynurenines. A tendency to an increase in the frequency of spontaneous spikes was also observed. The effect of the mutation on neurophysiological characteristics under study was recessive, i.e. it was observed only in homozygous individuals.

[Neuronal activity in a honey bee (Apis mellifera L.) with kynurenine deficiency]. / Osobennosti neironnoi aktivnosti u medonosnoi pchely (Apis mellifera L.) v usloviiakh defitsita kinureninov.

Neuronal activity of the antennal lobes, mushroom bodies, and cervical connective in wild-type honey bees and snowlaranija mutants was recorded at different stages of the ontogeny (on the 1st, 3rd, 7th, and 25th days). The mutation snowlaranija affects the structural gene of tryptophane oxygenase, the first key exzyme in the kynurenine pathway of tryptophane metabolism, and leads to a deficit of kynurenines. Changes in neuronal activity in nutant bees were most pronounced in the cervical connective. A significant decrease in the pulse rate was revealed only in homozygous but not in heterozygous individuals. This finding is in accordance with previously reported inhibitory effect of the mutation at the behavioral level. Less pronounced effects were obtained when the neuronal activity was recorded in the antennal lobes or mushroom bodies. This may be related to a complex character of biochemical changes in different parts of mutants brain.

[Adrenocortical tumors with neuroendocrine differentiation]. / Adrenokortikal'nye opukholi s neiroéndokrinnoi differentsirovkoi.

18 adrenocortical tumours and 5 pheochromocytomas were studied immunohistochemically. Expression of synaptophysin and chromogranin A was found in cells of cortical adenomas, "frontier" neoplasms and in 20-75% of carcinoma cells, this ultramicroscopically was confirmed by observation of typical neuroendocrine granules. Some groups of cells of cortico-medullary tumours also expressed proteins of neural differentiation (protein S-100).

[Study of myocardial morphology in chronic obstructive bronchitis complicated by pulmonary hypertension based on the results of endomyocardial biopsy]. / Morfologiia miokarda pri khronicheskom obstruktivnom bronkhite, oslozhnennom legochnoi gipertenziei, po rezul'tatam éndomiokardial'noi biopsii.

Endomyocardial biopsy along with right heart catheterization was first performed in 12 patients with chronic obstructive bronchitis complicated by transient or sustained pulmonary hypertension. Light and electron microscopic findings showed signs of severe myocardial dystrophy in 7 patients and prevalent hypertrophy in the remaining patients. Endomyocardial biopsy provided valuable information on the state of the myocardium, yielding evidence for the heretogeneous nature of right ventricular myocardial changes. Two morphological variants of cor pulmonale--hypertrophic and dystrophic--could be identified with regard to the findings.

[Clinico-morphological characteristics of dilated cardiomyopathy]. / Kliniko-morfologicheskie osobennosti dilatatsionnoi kardiomiopatii.

The paper presents the results of a clinicomorphological study of 50 patients with dilated cardiomyopathy. ECG, echocardiography, x-ray revealed atrial fibrillation, parasystole, extrasystole, impairment of intraventricular conduction, symptoms of a focal cicatricial myocardial lesion, high end-systolic and end-diastolic volumes, reduced ejection fraction, marked axial dilatation of the heart. Morphologic evaluation showed diffuse and diffuse microfocal cardiosclerosis, combination of sites of hypertrophic myocardiocytes with dystrophic foci, atrophy, sclerosis. Morphological evidence is available for arrhythmic, cardiomegalic, aneurysmic, infarction-like and pseudovalvular dilated cardiomyopathy.

[Myocardium in chronic obstructive lung diseases]. / Miokard pri khronicheskikh obstruktivnykh zabolevaniiakh legkikh.

The analysis of endomyocardial biopsies (10 specimens) and clinical observations suggests the conclusion: myocardial lesions in OPD patients with pulmonary hypertension are due to metabolic and hemodynamic disturbances. In addition to myocardial hypertrophy, myocardial dystrophy contributes to development of cor pulmonale.

[Clinico-morphological characteristics of pericardial mesothelioma]. / Kliniko-morfologicheskie osobennosti mezoteliomy perikarda.

The authors describe clinical and morphological features of a rare tumor, pericardial mesothelioma. Their findings lead them to a conclusion that the epithelioid cell form (tubular and papillary variants) is the most incident histologic form of this tumor. They emphasize that life-time diagnosis of pericardial mesothelioma is of paramount importance because rational chemotherapy permits prolongation of the patient's survival.

[Mechanisms of lesions of myocardial contractility in infectious-allergic myocarditis]. / Mekhanizmy povrezhdeniia sokratitel'nogo miokarda pri infektsionno-allergicheskom miokardite.

Clinical and morphologic analysis of 63 biopsy specimens and of 23 autopsy specimens has shown the leading role of immune inflammation with the development of delayed and immediate type hypersensitivity in injury to myocardial contractility. It is the immune inflammation that is responsible for disorders in electrolyte metabolism, microcirculation, sympathetic nervous system reactivity.

[The kynurenine pathway of tryptophan metabolism detected in the nervous system of Drosophila melanogaster]. / Kinureninovyi put' obmena triptofana obnaruzhen v nervnoiu sisteme Drosophila melanogaster.

Isolated thoracic ganglia were incubated in physiological solution containing 14C-tryptophan. After this procedure, they were homogenized in a 1 per cent solution of HCL in methanol, and supernatant was subjected to two-dimensional thin layer chromatography in the presence of tryptophan, kynurenine, 3-hydroxy kynurenine, as well as kynurenic, anthranilic and xanthurenic acids. The spots were cut out and counted by liquid scintillation technique. Except tryptophan, only kynurenine and 3-hydroxy kynurenine spots contained notable radioactivity. Therefore, at least the initial stages of kynurenine pathway operate in the nervous system of Drosophila melanogaster. This finding is in accordance with observations of the effects of kynurenines on insect behaviour.

Alternative procedures to aortobifemoral bypass grafting.

The outcome of 175 bypass procedures performed on 174 patients with symptomatic aortoiliac occlusive disease during a five-year period were analyzed. Fifty-nine patients underwent a standard aortofemoral bypass and 116 patients underwent one of three alternative procedures consisting of femoro-femoral, iliofemoral, or axillofemoral bypass. The operative stress, morbidity, mortality and long-term results were compared. Although the aortofemoral group had a higher three-year cumulative patency rate (89% vs 81%), the alternative procedure group had a lower operative mortality (1.8% vs 7%). In addition, the patients in the alternative procedure group were slightly older, had a higher percentage of procedures performed for limb salvage, and had a less optimal run-off status, yet the complication rate was significantly less than that of the aortofemoral group (p less than 0.05). The use of these alternative procedures should be considered for patients with symptomatic aortoiliac disease, who represent a moderate operative risk as well as those in a high risk category.

[Bioenergetics of the myocardiocytes in infectious-allergic myocarditis]. / Bioénergetika miokardiotsitov pri infektsionno-allergicheskom miokardite.

The role of myoglobin in myocardial bio-energetics was analyzed in cases of infectious-allergic myocarditis (38 endomyocardial biopsies and 18 autopsies). Myoglobin content is found to be directly related to the severity of the disease and the degree of circulatory compensation or decompensation. In conditions of progressive muscular cell dystrophy, an abrupt drop in myoglobin, detectable around the A discs, can be seen. In hypertrophic myocardiocytes of compensated circulation, myoglobin is detected as distinctly outlined large and small granules.