FEATURES OF HEMODYNAMICS IN VERTEBROBASILAR ARTERIAL SYSTEM IN YOUNG PEOPLE, DEPENDING ON BIOMECHANICAL DISORDERS OF THE MUSCULOSKELETAL SYSTEM.

In order to study the features of hemodynamics in the vertebral artery (VA), depending on the biomechanical disorders of the cervical spine (CS) and the musculoskeletal system as a whole 105 patients (53 females and 52 males, mean age - 38±5,9 years) having signs of the Vertebrobasilar insufficiency on the background of biomechanical disorders of the CS and the locomotor system as a whole were examined. The control group included 50 practically healthy persons (25 females and 25 males, mean age - 37±5,6 years). Physical examination included a clinical-neurological, vertebro-neurological examination (visual assessment of violations of statics and dynamics of the musculoskeletal system, measuring the craniovertebral angle (CVA) using a photogrammetric method, manual diagnostics for the detection of muscular-tonic syndromes and musculoskeletal dysfunction) and Doppler ultrasound of extra- and intracranial segments of VA. It was revealed the relationship between the violation of hemodynamics in vertebrobasilar system and pathobiomechanical changes of the musculoskeletal system in patients of young age. The leading pathogenetic role in the onset of hemodynamic disorders in VA belongs to a non-optimal static stereotype in the cervical region in the form of displacement of the regional center of gravity forward with the formation of a forward head position. It was revealed a positive correlation between the value of CVA and the degree of mobility of the craniovertebral transition by A. Stoddart (r = +0.79, p <0.05) and also - a negative correlation between CVA value and the level of blood flow reduction in VA during functional rotational tests (r=-0,69, p<0,05).

Inhibition of oxidative stress in brain during rat adjuvant arthritis by carnosine, trolox and novel trolox-carnosine.

Carnosine (CARN) is an anti-glycating agent able to quench superoxide, and to neutralize 4-hydroxynonenal. Trolox-carnosine (CARN-T) was synthesized because of its resistance against degradation and to improve CARN antioxidant capacity. We evaluated the impact of trolox (TRO), CARN and its derivative CARN-T on oxidative stress (OS) in brain during rat adjuvant arthritis (AA). The experiments were done on healthy, control arthritic and arthritic animals with administration of CARN 150 mg/kg b.w., TRO 41 mg/kg b.w. and CARN-T 75 mg/kg b.w. in a daily dose during 28 days. Antioxidants did not affect the body weight on day 14, but on day 28 TRO enhanced the weight reduction. On day 14 and 28 CARN-T and TRO reduced arthritic score. IL-1beta, MCP-1 and MMP-9 were measured in plasma on day 14. MCP-1 was decreased by CARN-T and TRO. All antioxidants reduced IL-1beta and MMP-9 levels. Malondialdehyde, 4-hydroxynonenal and protein carbonyls were increased in brain. CARN, CARN-T and TRO prevented higher lipid and protein oxidation in brain. CARN and CARN-T caused no weight reduction like TRO that has an advantage in inflammatory arthritis. Moreover the antioxidants administered had a similar therapeutic effects on arthritic score, markers of inflammation in plasma and OS in brain.

[Experimental study on the effect of low molecular DNA from salmon milt in pseudotuberculosis infection]. / Izuchenie deistviia nizkomolekuliarnoi DNK iz molok lososevykh ryb pri psevdotuberkuleznoi infektsii v éksperimente.

The effect of low molecular DNA from salmon milt (nDNA) in experimental pseudotuberculosis in mice was studied. When nDNA was admiministered orally, dissemination of the organs by Yersinia pseudotuberculosis lowered and the survival of the animals infected with 100-percent lethal dose of the bacteria increased. nDNA decreased contamination of the epithelial cells by the microbe in vitro and prevented the lethal effect of the Y. pseudotuberculosis toxins on the mice.

In search of an elusive hard threshold: a test of observer's ability to order sub-threshold stimuli.

The contrast transducer function (d' vs. contrast) for sine gratings was claimed to come up from some non-zero contrast value rather than from the origin. This implies that there is a point (a hard threshold) on the grating contrast axis below which observers could not distinguish between presentations containing gratings and those containing a homogeneous field. We studied the ability to order sub-threshold square wave gratings and found, to the contrary, that observers were able to do this no matter how low the contrasts. At the same time, the observers failed to order the sub-threshold gratings when they were of the same contrast. The latter is inconsistent with signal detection theory which predicts that an observer's judgements are based on the same ordered set of sensory states irrespective of whether the stimuli differ or are the same. On the other hand, these data can be reconciled with the notion of a threshold if the latter is thought of as a fuzzy rather than a sharp margin on the contrast axis.

[Non-invasive estimation of the temperature gradient of internal living tissue layers by ultrasound method]. / Neinvazivnaia otsenka gradienta temperatur vnutrennikh sloev zhivykh tkanei ul'trazvukovym metodom.

The paper deals with the designing of equipment for telecontrol of changes in the temperature of the internal layers of objects, which cannot be measured by contact methods. The bases for this are an analysis of the ultrasound oscillations reflected from the internal heterogeneities of the environment, as well as restoration of the pattern of a pressure propagation velocity along the sounding beam. The feasibility of telecontrol of temperature is analyzed by using the boundary integrated equations. A procedure is proposed on the basis of the difference-phase method for estimating the velocity of propagation of reflected signals. Requirements for the equipment and algorithms for processing the signals observed are formulated. Ways for further studies are directed.

[Use of immunomodulators isolated from marine invertebrates for reducing the toxic effects of thermostable toxin and lipopolysaccharides from Yersinia pseudotuberculosis on a macroorganism]. / Ispol'zovanie immunomoduliatorov iz morskikh bespozvonochnykh dlia snizheniia toksicheskogo deistviia termostabil'nogo toksina i lipopolisakkharidov Yersinia pseudotuberculosis na makroorganizm.

The possibility to use immunomodulators isolated from marine invertebrates for the lowering of the toxic effects caused by Yersinia pseudotuberculosis thermoresistant toxin and lipopolysaccharide was investigated. Effects were evaluated by the animals survival rate in per cent and mice average lifetime after toxin lethal dose injection. It was shown that polypeptide gangleen when compared to timalin as well as glycanes mitilane and strombus had dose-dependent protective effect. These substances increased animals survival rate to 15-17 per cent and prolonged life period for about two times when compared to control group. These results demonstrates the possibility to use investigated immunomodulators is clinical practice at the treatment of the patients with pseudotuberculosis.

[Effect of peptide immunomodulator gangleen on the activity of Yersinia pseudotuberculosis thermostable toxin in oxidant and antioxidant systems of human leukocytes]. / Korrektsiia vozdeistviia termostabil'nogo toksina Yersinia pseudotuberculosis na okislitel'nuiu i antiokislitel'nuiu sistemy leikotsitov krovi cheloveka immunomoduliatorom peptidnoi prirody gangliinom.

The ability to correct activity of Y. pseudotuberculosis thermoresistant toxin on antioxidative enzymes and on active oxygen forms in neurophiles and mononuclears was investigated. Toxin at concentration 0.5 and 2.5 mcg/ml did not change O2- production and activity of superoxidedismutase (SOD) and glutathione peroxidase (GP), but significantly enhanced catalase and glutathiont reductase (GR) activity. Gangleen at concentration 0.0002-0.2 mcg/ml, when added to incubation medium with toxin, stimulated production of active oxygen forms and activity of SOD, catalase, GP in both types of leucocytes, but decreased activity of GR in mononuclears. The results of investigation proves the ability to use gangleen in correction of immune system disorders caused by Y. pseudotuberculosis thermoresistant toxin.

High-spatial-frequency tritanopia: S-filling-in or S-filtering-out?

It has long been an accepted fact that a small test field presented against a large background may change its colour appearance because the test-field background contrast is attenuated by the receptor colour channels unequally (Willmer, 1944 Nature 153 774-775; Hartridge, 1947 Philosophical Transactions of the Royal Society of London, Series B 232 519-671). Such an effect is usually called small-field tritanopia. However, as shown in the present report, a similar colour illusion can be achieved with a large test field as well, provided its spatial-frequency content is high enough to reveal the differential drop of contrast sensitivity for the receptor colour channels (high-spatial-frequency tritanopia). A few demonstrations are presented which show that a traditional explanation of high-spatial-frequency tritanopia (including small-field tritanopia), based on the hypothetical process of filling-in, is not correct. An alternative account, based on spatial filtering within the receptor colour channels, is put forward.

The role of vergence in the perception of distance: a fair test of Bishop Berkeley's claim.

Binocular eye movements were measured while subjects perceived the wallpaper illusion in order to test the claim made by Bishop Berkeley in 1709 that we perceive the distance of nearby objects by evaluating the vergence angles of our eyes. Four subjects looked through a nearby fronto-parallel array of vertical rods (28-35 cm away) as they binocularly fixated a point about 1 meter away. The wallpaper illusion was perceived under these conditions, i.e. the rods appeared farther away than their physical location. We found that although binocular fixation at an appropriate distance was needed to begin perceiving the wallpaper illusion (at least for naive observers), once established, the illusion was quite robust in the sense that it was not affected by changing vergence. No connection between the apparent localization of the rods and vergence was observed. We conclude that it is unlikely that vergence, itself, is responsible for the perceived distance shift in the wallpaper illusion, making it unlikely that vergence contributes to the perception of distance as Bishop Berkeley suggested. We found this to be true even when vergence angles were relatively large (more than 2 deg), the region in which the control of vergence eye movements has been shown to be both fast and effective.

[Use of a nebulizer as a new method of drug administration in treating dyspnea attacks in patients with bronchial asthma]. / Ispol'zovanie nebulaizera kak novogo metoda dostavki lekarstvennykh preparatov dlia kupirovaniia pristupov udush'ia u bol'nykh bronkhial'noi astmoi.

AIM: To try nebulizer for delivery of berodual solution to cope with asphyxia attacks in bronchial asthma (BA) patients. MATERIALS AND METHODS: Nebulizer was used in 86 patients suffering from bronchial asthma (BA) of different severity treated with standard therapy. Berodual inhalations (1 ml solution) were performed by means of nebulizer Pari Boy. Heart rate, respiratory movements rate, peak flowmetry were evaluated before and after the inhalations. RESULTS: One inhalation was enough for arrest of asphyxia in 70 patients (81.4%), two inhalations relieved the attack in 9 patients (10.46%), 7 patients (8.14%) needed intravenous infusion of euphylline solution for a complete attack arrest. Side effects were not registered. CONCLUSION: Berodual solution inhalations via nebulizer proved clinically and cost effective.

Lightness induction revisited.

Lightness induction is the classical visual phenomenon whereby the lightness of an object is shown to depend on its immediate surround. Despite the long history of its study, lightness induction has not yet been coherently and satisfactorily explained in all its variety. The two main theories that compete to explain it descend (i) from H von Helmholtz, who believed that lightness induction originates from some central mechanisms that take into account the whole viewing situation, with particular stress upon the apparent illumination of the object; and (ii) E Hering who argued in favour of more peripheral sensory mechanisms based on local luminance contrast. The balance between these theories has recently been shifted towards Helmholtz's position by E H Adelson who has provided additional evidence that lightness induction depends on perceptual interpretation and, particularly, on apparent transparency. I challenge Adelson's conclusions by introducing modified versions of his tile pattern that use luminance gradients. In the first of these new demonstrations there is a strong lightness induction even though no apparent transparency is experienced. In the second there is a clear impression of transparent strips, yet no lightness induction is present. And the third shows that breaking up the Adelson tile pattern, while it affects neither the impression of transparency nor the type of grey-level junctions, makes the lightness-induction effect vanish. This implies that Adelson's illusion can be accounted for by neither local contrast, nor the apparent transparency, nor the type of grey-level junctions. Presented here is an alternative look at lightness induction as a phenomenon of the pictorial (as contrasted to natural) vision, which rests on the lightness-shadow invariance, much as Gregory's 'inappropriate constancy scaling' theory of geometrical illusions rests on the apparent size-distance invariance.

On derivation of spectral sensitivities of the human cones from trichromatic colour matching functions.

Despite the recent advance made by using the direct methods of retinal densitometry, microspectrophotometry and suction electrophysiology, the psychophysical approach based on colour matching data still remains an important source of accurate information about the spectral sensitivity of the cone photoreceptors in the human visual system. However, the commonly used technique of estimating cone sensitivities, based on the assumption that dichromacy is caused by the lack of one of the three types of the cone photoreceptors, requires the colour matching functions not only from trichromatic observers but from dichromats as well. Here we evaluate an alternative approach, originally put forward by Bongard and Smimov, that derives cone spectral sensitivities from colour matching functions only; without resorting to colour deficiency or any other data. When applied to CIE standard colour matching functions, this method yields curves of spectral sensitivities that are close to the classical Smith-Pokorny fundamentals, though the long-wave cone is shifted towards the short-wave region of the spectrum by 5 nm, as compared with Smith and Pokorny's results.

[The chronocorrection of disorders in the blood coagulation rhythm with kurantil in patients with decompensated rheumatic heart defects]. / Khronokorrektsiia narushenii ritma gemokoaguliatsii kurantilom u bol'nykh s dekompensirovannymi revmaticheskimi porokami serdtsa.

The circadian pattern of hemocoagulation was studied in patients with decompensated rheumatic heart disease (DRHD) concurrent with stages I-II circulatory failure (CF) during complex treatment or medical treatment with disaggregants. Biorhythmological studies demonstrated that in patients with DRHD and CF chronotherapy with curantyl had some advantages over the traditional therapy during complex drug therapy. In these patients, the chronopatterns of circadian rhythms of hemocoagulative parameters tended to normalize under the influence of curantyl chronotherapy, by diminishing the signs of external desynchronization. Advantages of chronotherapy over the traditional treatment found in patients with DRHD and stages I-II CF, as manifested by its clinical effect in shorter periods (on days 4-5) when small daily and course doses of the drug were used. Based on the biorhythmological studies of hemostatic parameters, a method of curantyl chronotherapy was developed for patients with DRHD and stages I-II CF, which may optimize the therapeutical process in patients with this abnormality.

Convexity of a set of subthreshold stimuli implies a peak detector.

It has been shown that for every model of detection (whether single- or multi-channel, with linear or non-linear channels, and whatever decision rule), provided that it predicts a convex set of subthreshold stimuli, there is a psychophysically equivalent peak detector made up of a collection of linear analysers followed by a maximum-output decision rule. In this paper, the equivalent peak detector representations of some widely accepted detection models are calculated. The calculations rest on a general technique for deriving, from a given model, a formula which specifies the analyser most sensitive to any given stimulus.

On cardinal directions in spatial pattern space and falsifying multi-channel detection models.

It has been generally recognised that in its early stages the human visual system comprises a set of independent subsystems, or channels, acting in parallel. There is general agreement that the receptive fields of neurones constituting the channels overlap considerably, making the task of selectively stimulating individual channels nontrivial. Since such a task is important for estimating the spatio-temporal characteristics of these channels, a method for determining a set of spatial patterns which stimulate multiple channels independently, irrespective of how their receptive fields overlap, is presented here. As an example such patterns were calculated for Wilson and Bergen's model (Wilson and Bergen, 1979, Vision Res. 19, 19-32). Using the modification of the subthreshold summation technique (Logvinenko, 1995, Biol. Cybernet. 73, 547-552) it is shown that in reality these stimuli are not processed independently. It follows that Wilson and Bergen's model involves a set of channels which is inappropriate or incomplete or both.

On deriving analyser characteristics from summation-at-threshold data.

It has been proved that a detection process may be accounted for by a simple two-state model consisting of a collection of linear analysers followed by a maximum-output decision rule provided that a set of all threshold stimuli is convex. A non-parametrical method to identify the analysers constituting such a model is proposed.

[The cholesterol esterase activity of the blood monocytes and alveolar macrophages in patients with chronic bronchitis]. / Aktivnost kholesterinésterazy monotsitov krovi i al'veoliarnykh makrofagovu bol'nykh khronicheskim bronkhitom.

The activity of cholesterol esterase (CE) in blood monocytes and alveolar macrophages (AMF) of bronchoalveolar fluid (BAF) according to Brecher et al., cell composition of endobronchial cytogram were investigated in 32 patients with chronic bronchitis (CB) and control subjects. In CB sufferers CE activity in AMF was inhibited, while in monocytes it was elevated reaching maximal values in purulent bronchopulmonary CB. Determination of CE activity in AMF and peripheral blood monocytes in CB may serve an additional diagnostic indicator of impaired lipid metabolism and suggests new approaches to investigation of CB pathogenesis.

Convergence as a cue for distance.

Binocular eye movements were measured in subjects experiencing the wallpaper illusion. It was found that a physical displacement of the fixation point by more than 1 m out of the plane of apparent localisation of the strips had no influence on the illusory location of these strips. Hence, illusory localisation in the wallpaper illusion is independent of the actual magnitude of the subject's convergence angle, once the illusion has come into existence. This result suggests that convergence does not serve as a source of information about apparent distance, at least in the wallpaper illusion.

Trade-off between achromatic colour and perceived illumination as revealed by the use of pseudoscopic inversion of apparent depth.

The albedo hypothesis was tested under apparent transformations of perceived illumination and achromatic colour induced by pseudoscopic inversion of apparent depth. Looking through a pseudoscope made a cone attached to a vertical white screen look like a conical hole in the screen. This in turn caused the shadow which the now 'invisible' cone cast on the screen to change its appearance and to look like a darkly pigmented area. The darkness of the shadow before the pseudoscopic reversal and greyness of colour afterwards were measured by means of psychophysical scales for darkness and greyness set by the bisection method. Contrast of the shaded area was varied from 0.17 to 0.96 in 7 steps, the mean illuminance of the screen having been maintained at 40 1x. Although the albedo hypothesis in its classical form was not confirmed, it was found that darkness of shadow varied linearly in inverse proportion to greyness of colour within the entire contrast range. This is in agreement with the hypothesis that achromatic colour and perceived illumination are inversely proportional to each other while the retinal illumination is constant.

[The characteristics of the fetal-maternal-placental blood flow in habitual abortion]. / Osobennosti plodovo-matochno-platsentarnogo krovotoka pri privychnom nevynashivanii beremennosti.

Dopplerometry of uterofetoplacental blood flow in 59 women at pregnancy terms of 24 to 40 weeks with a history of habitual abortions revealed disordered blood flow in approximately 60% of cases. Pathologic shifts first develop in a fetus as a rule. Moderate disorders of the uterofetoplacental blood flow in women with a history of habitual abortions do not result in the majority of cases in chronic disorders of fetal status, whereas marked disorders of blood flow often lead to fetal intrauterine suffering.