Chronic Effects of Modeled Myocardial Infarction, Thoracic Trauma, and Denervation of Hind Limb on Rheographic Parameters of Rat Femoral Arteries In Situ.

In experiments on narcotized male rats (n=85), the mean electroimpedance Z and peak-to-peak magnitudes (the swing ranges) of passive (ΔZp) and active (ΔZa) pulsatile electroimpedance oscillations of isolated segment of femoral arteries were determined in situ. These rheographic parameters (RP) were measured in intact animals and in those with modeled chronic myocardial infarction, chronic denervation of the right hind leg, as well as in rats subjected to sham operations to mimic denervation or infarction (with thoracic trauma). The rats with modeled myocardial infarction demonstrated decreasing trends of all RP. In sham-operated rats with thoracic trauma, ΔZp increased significantly on postsurgery months 2-4 by 4.3 times in comparison with the control. No essential correlation was found in denervated rats between RP of any femoral artery and severity of neuropathic pain syndrome assessed by autotomy of the operated leg. In these rats, the mean electroimpedance Z of any femoral artery was significantly greater than the control level. They demonstrated especially high values of ΔZp with significant difference between ΔZp of innervated and denervated hind leg. In denervated rats, ΔZa was significantly greater than the control value without significant difference between ΔZa of both femoral arteries. The paradoxically great increase of ΔZp (100- and 50-fold for innervated and denervated legs, respectively) and a significant 3-fold increment of ΔZa in both hind legs provoked by denervation of one of them are discussed in relation to searching for the ways of systemic influences on vascular network in clinics and experiments.

Pelvic Electric Potential as a Marker of Autonomic Dysfunctions and Risk Factor of Neurogenic Arrhythmias in Humans.

Differential high-resolution ECG (V1-V2) and pelvic electric potential measured between the coccyx and perineum were recorded simultaneously in resting supine position in men with autonomic nervous system disorders (N=37). In healthy volunteers (N=23), the effective (rms) value of PEP presented by median and interdecile range was 30 (20-80) µV within the frequency band of 0.03-80 Hz. In patients, the corresponding value was significantly higher: 140 (80-280) µV. In both groups, the amplitude harmonic spectrum of pelvic electric potential decreased monotonically with frequency according to 1/f1.6 law. In some patients (N=16), rare single or grouped high-amplitude impulses (up to 1 mV) of pelvic electric potential with total duration of about 1 sec were observed; of them, some persons (N=7) demonstrated practically one-to-one synchronous relations between these impulses and arrhythmia episodes indicating abnormal activity of the autonomic nervous system as their most probable common cause. The high-amplitude pelvic electric potential impulses were also observed in ECG records as interference signals with an amplitude attaining 50 µV. Thus, high-resolution ECG and pelvic electric potential can reveal the risk of abnormal neurogenic influences on the heart. The data obtained are discussed in relation to diagnostics of the autonomic nervous system disorders, neurogenic arrhythmias, and risk of sudden cardiac death.

[Conformational fluctuations in chloroplasts]. / K voprosu o konformatsionnykh kolebaniiakh khloroplastov.

Characteristic features of conformational changes in chloroplasts have been studied by microfilm technique at BMI-13 installation. The oscillatory character of changes in chloroplast cross-section area in time, determined earlier by the tele-lazer microscopy technique, has been confirmed by our data. When chloroplasts are simultaneously seen in the microscope it is possible to observe their synchronous oscillation. The stationarity check of conformational changes shows that is a non-stationary process in the general case. So it is concluded that the standard technique of analysing accidental non-stationary processes can be used for study of conformational changes in chloroplasts provided that the corresponding parts of their kinetics are selected or trends are eliminated depending on the type of non-stationarity.

[Use of statistical analysis in studying the conformational oscillations of chloroplasts]. / Primenenie statisticheskogo analiza dlia issledovaniia konformatsionnykh kolebanii khloroplastov.

Conformational oscillations of chloroplasts have been studied by the statistic analysis technique. Statistic characteristics of the parameters describing the process of chloroplast cross-section oscillations in time are given. According to the statistic analysis results it can be suggested that conformational oscillations of chloroplasts have the multilevel structure. The suggestions concerning causative factors of that multilevel organization of oscillating process are also advanced.

[Application of autocorrelation analysis to the study of conformational changes in chloroplasts]. / Primenenie avtokorreliatsionnogo analiza dlia issledovaniia konformatsionnykh kolebanii khloroplastov.

The process of conformational oscilations of chloroplasts has been studied using autocorrelation analysis technique. The process is shown to differ from the non-correlated random process of "white noise" type. Four types of autocorrelogram have been obtained which are characteristic of the phone oscilations of chloroplast cross-section area in time. The authors suggest that the different types of autocorrelograms are due to the different possible states of chloroplasts. The periodical components with the frequency of 16; 10--11; 8; 4; 2; 0.5 and 0.3 hertz have been obtained in the kinetics of chloroplast cross-section changes. Two magnitude ranges have been found for the moment of first zero volume in autocorrelation function (ACF): 5--10 and 15--20 shifts. ACF slow attenuation towards zero may be due to quite a good organization of the process of chloroplast conformational oscilations and availability of the well-developed control system of adaptive type.

[Humoral autoimmunity markers in autoimmune endocrine diseases]. / Markery gumoralnogo autoimmuniteta pri autoimmunnykh éndokrinnykh zabolevaniiakh.

To clarify the value of autoantibodies as risk factors of complications in various endocrine abnormalities, the incidence of autoantibodies to thyroid microsomal antigen (ATMA), thyroglobulin, and the surface antigens of the rat islet, adrenal cortex, adenohypophyseal cells and human skin fibroblasts was studied in patients with insulin-dependent mellitus (IDDM), at the onset of the disease and during one-year insulin therapy, non-insulin-dependent diabetes mellitus (NIDDM), Hashimoto thyroiditis, Graves' disease, diabetes associated with thyroidal dysfunction, euthyroid polynodular goiter, Schmidt and polyglandular syndromes and in the population. The antibodies were determined by ELISA. Polyclonal activation of the immune system was found in all abnormalities, except in polyglandular in children. The proportion of patients with more than one type of antibodies was minimal (26.4%) in IDDM and maximal (62.0%) in Graves' disease. Among IDDM patients, polyclonal activation of the immune system was observed more often in women than in men (48.5 vs 8.5%). The persistence of antibodies to fibroblasts in IDDM patients was associated with the development of vascular complications. The latter were observed in 4 of 7 patients who had these antibodies during a year and in none of negative patients. Thus, fibroblast antibodies may have a predicative significance for the development of late diabetic complications. The highest prevalence of these antibodies was discovered in Graves' disease (37.9%) wherein the antibodies may be involved in the development of exophthalmus and pretibial mixedema. Thyroidal dysfunction developed in all IDDM patients with ATMA preserved during a year and in none ATMA-negative patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[The special reaction of photophosphorylation using epsilon ADP--a fluorescent analog of ADP]. / Issledovanie osobennostei reaktsii fotofosforilirovaniia s pomoshch'iu epsilon ADP--fluorestsentnogo analoga ADP.

Photophosphorylation of epsilon ADP in a chloroplast synthetase system reconstituted with CF1 or with CF1 modified by covalently bound epsilon ADP has been studied. The reconstitution of EDTA-treated chloroplasts with CF1 restores the photophosphorylating activity to about 90%. When the CF1 modified by covalently bound epsilon ADP is used for reconstitution the photophosphorylating activity of EDTA-treated chloroplasts is restored to 37%. Based on the results of a photochemical study of the chloroplast ATP-synthetase system reconstituted with CF1 with covalently bound epsilon ADP it may be assumed that the substrate, adenine, participates in proton translocation to inorganic phosphate in the active center of the coupling enzyme during photophosphorylation.

[Properties of epsilon-ATP hydrolysis by CF1-ATPase from pea chloroplasts]. / Osobennosti gidroliza epsilon-ATP CF1-ATPazoi khloroplastov gorokha.

The ATPase activity of CF1 isolated from pea chloroplasts with epsilon-ATP, the fluorescent analog of ATP and ATP used as substrates, in the presence of Mg2+, Ca2+ and sodium sulfite (stimulator of the ATPase activity) was studied. The rate of epsilon-ATP hydrolysis in the presence of Mg2+ is nearly two times as low as that of ATP; an addition of sodium sulfite to the reaction mixture increases the reaction rate without changing the above ratio. The rate of Ca2+-dependent hydrolysis of epsilon-ATP is rather low as compared to that in the presence of Mg2+. epsilon-ADP is a competitive inhibitor of Mg2+-dependent ATPase reaction and inhibits this process in the presence of Ca2+, the inhibition being of a mixed type. Modification of CF1 by covalent binding of epsilon-ADP results in a 70-80% decrease of the Mg2+-dependent ATPase activity, the Ca2+-dependent ATPase activity is changed only insignificantly thereby. The differences in the activation of ATP and epsilon-ATP hydrolyses by Ca2+ and Mg2+ can be accounted for by the existence of two sites in the active center of CF1, which are specific for Mg2+ and Ca2+, respectively. It is concluded that the binding of epsilon-ADP occurs in the Mg2+-dependent ATPase site of the active center.

[Evaluation of changes in free energy of proteins and biomembranes under pH-induced conformational transitions. Coupling membranes of peak chloroplasts]. / Metod otsenki velichiny izmeneniia svobodnoi energii belkov i biomembran pri pH-indutsirovannykh konformatsionnykh perekhodakh. Sopiagaiushchie membrany khloroplastov gorokha.

It was shown that changes in the free energy during pH-induced conformational transitions can be calculated from the buffer spectrum of the biopolymer. These changes are similar to those of the chemical potential of cooperatively protonating groups (delta Go = 2,3 RT (pKt--pKi)Nt) and can be determined independently for each transition of the complex object. Consequently, in case of biomembranes with the ionic strength greater than or equal to 0,1 it is possible to determine not only the maximal efficiency of each transition according to the formula magnitude of delta Go congruent to 2,3 RTNt, but also that of the membrane component which initiates the given transition. Thus, a study of the photo-dependent buffer spectrum of the coupling membranes of chloroplasts showed that in the membrane the ATPase complex performs a reversible conformational transition within the pH region of photophosphorylation with the energy of 100--130 kcal/mol for the coupling factor or 190--260 cal/mol for the chlorophyll.

[Role of the pterin component in light and dark oxygen consumption by chloroplasts]. / Ob uchastii pterinovogo komponenta v svetovom i temnovom pogloshchenii kisloroda khloroplastami.

The effects of ferredoxin and the pterin component from pea chloroplasts on oxygen consumption by pea and spinach chloroplasts in the dark and in the light were studied. In the absence of the pterin component the illuminated chloroplasts from both sources weakly reduce oxygen. An addition of the pterin component produces different effects on oxygen consumption by pea and spinach chloroplasts: the former efficiently reduce oxygen after addition of a single pterin component, while the latter require the presence of ferredoxin as well. The data obtained suggest that in pea chloroplasts there exists a ferredoxin-independent pseudocyclic electron transport mediated by pterin. In spinach chloroplasts this electron transport is ferredoxin-dependent. In the presence of pterins the chloroplasts are capable of carrying out dark reduction of O2, using NADPH and H+ as electron donors.

[Participation of the iron-containing pterine-protein complex in NADP reduction and electron transport]. / Zhelezosoderzhashchii pterin-belkovyi kompleks; uchastie v vosstanovlenii NADP i trans orte elektronov

A factor of protein nature, containing pteridines and iron ions was isolated from pea leaves. The compound was shown capable of activating NADP reduction during chloroplasts illumination in the absence of ferredoxin. The compound was termed "NADP-reducing factor" (NRP). Freshly isolated NRF in combination with the protein possessing the NADP-reductase activity, reduces NADP in the dark. The factor accepts the electron from the reaction site of the first photosystem and activates hydrogen liberation in the systems, containing hydrogenase. A possibility of an existence of an additional site of NADP reduction in chloroplasts is discussed.

[Association of multinodular euthyroid colloid goiter with various genetic markers]. / Ob assotsiatsii mnogouzlovogo kolloidnogo éutireoidnogo zoba s nekotorymi geneticheskimi markerami.

Distribution of blood groups ABO, Rh, P1, and MN was studied in 85 patients with multinodular euthyroid colloid goitre. An association has been revealed between the presence of this disease and MN blood group, as well as the absence of P1 antigen. These results permit us considering MN blood group and P1 antigen absence as factors of risk for multinodular euthyroid colloid goitre.

[Buffer capacity of polyproton substances]. / Bufernaia emkost' poliprotonnykh obdektov.

Mathematical analysis of protolytic properties of a polyelectrolite with arbitrary set of stepwise dissotiation constants is carried out, based on disintegration of summary titration curves and buffer capacity for basic functions. It is demonstrated, that in some cases (for example, investigation of biomembranes and their components) simplified disintegration variants can be used. Buffer titration curve of biopolymers and biomembranes is a "buffer spectrum", the position of bands on the pH scale, their intensity and half-width being determined by the nature of the object (the quantity and quality of hydrophilic groups and the set of its conformation states). Sharp peaks of the buffer spectrum correspond to the conformation transition of the object, and their half-width on the pH scale determines the cooperative degree of each conformation transition. The mathematical analysis described is not specific to the formation of polyprotonic complex, and it can be used in investigation of the complex formation with any monodentant ligand. It is concluded that the method described can be used in the investigation of complex biomembranes and different processes, in which these membranes participate.

[Adenylate kinase activity of phycobilisomes from the blue-green algae Microcystis aerogenosa]. / Adenilatkinaznaia aktivnost' fikobilisom, vydelennykh iz sinezelenoi vodorosli Microcystis aerogenosa.

The phycobilisomes (PBS) from the blue-green algae Microcystis aerogenosa was found to possess the adenylate kinase activity. The enzyme activity of PBS is kept for 2 weeks, reaching its maximum on th 2nd-4th day after PBS isolation from the cells, and is retained after passage of freshly isolated PBS through a column with Sephadex G-25. The adenylate kinase activity of PBS is thermostable, depends on the protein concentration in the sample, undergoes activation by white light and is inhibited by glutaric aldehyde. The enzyme activity is presumably determined by the components of the low molecular weight protein fraction of non-pigment origin, which are constituents of PBS.

[Some peculiarities of the reaction kinetics of ATP hydrolysis by Ca2+-dependent ATPase of chloroplasts]. / Nekotorye osobennosti kinetiki reaktsii gidroliza ATP Ca-zavisimoi ATPazoi Khloroplastov

The dependence of the reaction rate of ATP hydrolysis by CF1-ATPase of chloroplasts on the substrate (CaATP) concentration is of complex nature. It is assumed that such dependence may be due to either conformational changes of the enzyme during the increase in CaATP content in the reaction medium, or consecutive binding of the substrate to its active sites, differing in their affinity to the substrate of the reaction.