Postradiation disturbances in the cyclic AMP system of lymphocytes of the mouse spleen and thymus

In the early periods after irradiation of muscles in a dose of 800 rad changes in the activity of the enzymes of cyclic AMP metabolism are found in the lymphocytes of the spleen and thymus. The postradiation disturbance of the relative activities of these enzymes leads to changes in the steady-state intracellular cyclic AMP concentration. It is also shown that irradiation reduces the ability of lymphocytes to respond to isoproterenol by accumulating cyclic AMP.Laboratory of Radiation Biophysics, Department of Biophysics, Biological Faculty, M. V. Lomonosov Moscow State University. (Presented by Academician of the Academy of Medical Sciences of the USSR S. E. Severin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 164–167, February, 1978.     

Potentiating action of metabolic products of blood lymphocytes on polymorph vulnerability

The supernatant obtained after culture of sensitized blood lymphocytes with an appropriate allergen (tuberculin) potentiates injury to polymorphs (V. A. Fradkin's index of blood neutrophil injury).Laboratory of Standardization and Control of Infectious and Noninfectious Allergens, L. A. Terasevich State Research Institute of Standardization and Control of Medical Biological Preparations, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado). Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 6, pp. 729–731, June, 1977.     

Electrophoretic separation of lymphocytes from rat spleen and thymus and their response to mitogens in vitro

Electrophoretic mobility (EPM) of lymphocytes from the thymus and spleen of Wistar and August rats was investigated by free flow electrophoresis and the ability of lymphocytes with different surface electric charges to undergo mitogenic transformation under the influence of phytohemagglutinin and concanavalin A was compared. An in vitro culture showed that splenic lymphocytes can be divided into two principal groups depending on their surface charge: cells with high and low mobility respectively. Separation of the thymocytes showed them to be a group of cells consisting of several (8 to 10) fractions differeing in EPM. Ability of the lymphocytes to be stimulated by mitogens was shown to depend on their surface charge. Stimulation of [³H]thymidine incorporation was observed during exposure of splenic lymphocytes with high mobility in an electric field to mitogens. Lymphocytes with low mobility were not stimulated by mitogens. The subpopulation of thymocytes with low EPM was not stimulated by concanavalin A. Rat thymocytes were shown virtually not to react to phytohemagglutinin irrespective of their EPM.Laboratory for Organ and Tissue Transplantation, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kovanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 322–324, September, 1979.     

Inhibition of transformation of phytohemagglutinin-stimulated lymphocytes by neutral SH-dependent splenic proteinase

The effect of neutral SH-dependent splenic proteinase on the intensity of transformation of human peripheral blood lymphocytes was studied. Proteinase (1–10 g ml) was shown to inhibit transformation of phytohemagglutinin (PHA)-stimulated lymphocytes but to have no effect on spontaneous transformation. Proteinase did not change the mitogenic properties of PHA and had no cytotoxic action. Consequently, inhibition of transformation of the stimulated lymphocytes either was the result of the direct action of proteinase on the cell or was connected with the formation of a suppressor factor.Laboratory of Immunogenetics, Institute of Organ and Tissue Transplantation, Ministry of Health of the USSR. Laboratory of Biochemistry and Chemical Pathology of Proteins, Institute of Biological and Medical Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 324–326, September, 1979.     

Spectral moments of mechanomyographic signals recorded with accelerometer and microphone during sustained fatiguing contractions

The aim of this study was to analyse the trends of the first three power spectral moments of the mechanomyogram (MMG) signal recorded by a microphone (MMG_MIC) and an accelerometer (MMG_ACC) during sustained contractions. MMG signals were recorded from the biceps brachii muscle in 14 healthy male subjects during a 3 min isometric elbow flexion at 30% of the maximal voluntary contraction. MMG absolute and normalised root mean square (RMS), mean power frequency (MNF), power spectral variance (Mc₂), and skewness (μ₃) were computed. For both MMG_MIC and MMG_ACC, absolute and normalised RMS and Mc₂ increased while MNF and μ₃ decreased with contraction time (P<0.001). The rates of change of RMS over time were significantly correlated (P<0.001) for MMG_MIC and MMG_ACC but not correlated for spectral moments. The coefficient of variation of RMS was higher for MMG_MIC than for MMG_ACC, while the opposite was observed for μ₃ (P<0.05). It was concluded that higher order spectral moments of the MMG signal change during sustained contraction, indicating a complex modification of the shape of the power spectrum and not just scaling of the bandwidth. This is most likely due to the additional motor unit recruitment with fatigue and to the non-linear summation of motor unit contributions to the signal. Moreover, the characteristics of MMG signals recorded with microphones and accelerometers have important differences, which should be taken into account when comparing results from different studies.Submitted to: Medical and Biological Engineering and Computing     

Immunologic activity of human lymph cells in the blast transformation reaction

The immunologic activity of lymph cells obtained in the course of therapeutic drainage of the thoracic duct was studied in 14 patients with subhepatic jaundice of varied genesis. The blast transformation of lymphocytes reaction showed that lymphocytes from lymph are capable of blast formation when exposed to the action of phytohemagglutinin, antilymphocytic -globulin, and certain bacterial antigens. The highest intensity of the reaction was found in cultures of lymph lymphocytes taken for these purposes on the 2nd–3rd days after the beginning of lymph drainage. In the course of lymphorrhea the ability of stimulated lymph cells to undergo blast formation is reduced. In the period of lymph drainage, no blast formation takes place in stimulated cultures of patients' blood cells. The majority of antigen-sensitive lymphocytes is thus in a reserve state in the lymphoid tissue of the body.Department of Infectious Diseases and Course in Emergency Surgery, V. I. Lenin Kazan' Postgraduate Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 1, pp. 33–35, January, 1980.     

Intravital determination of pH gradient between cytoplasm and lysosomes in human fibroblasts from normal subjects and patients with lysosomal storage diseases

Institute of Biological and Medical Chemistry, Academy of Medical Sciences of the USSR, Moscow, M. V. Lomonosov Moscow State University. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 5, pp. 495–498, May, 1991.     

Apoptosis-inducing protein derived from hepatocyte selectively induces apoptosis in lymphocytes

The liver is where lymphocytes undergo activation-induced cell death (AICD) at the resolution phase of an immune response, which is crucial for homeostasis of the immune system and prevention of autoimmunity. Exploring the machinery of AICD in the liver, we found that a primary culture supernatant of murine hepatocytes had an antiproliferative effect on antigen-stimulated T clone and T lymphoma cells. Biological study showed that the antiproliferation was due to induction of apoptosis in a caspase-dependent manner. The apoptosis-inducing potential was sensitive to trypsin, heat (> 70 degrees ) and acid (< pH 5) treatment but could not be neutralized by anti-tumour necrosis factor-alpha, anti-Fas ligand, or anti-transforming growth factor-beta antibodies. Biochemical study of the isolated and purified apoptosis-inducing component from the supernatant showed that it was a protein with a molecular mass of about 68,000-70,000. It induced apoptotic change in murine T and B cells, and to a lesser degree, in human lymphoid cells, but not in macrophages. Biochemical and biological characteristics distinguish this protein from others that have been reported to induce apoptosis of lymphocytes. The identification of an apoptosis-inducing protein derived from murine hepatocytes, which selectively induces apoptosis in lymphocytes, suggests one possible mechanism for immune suppression in the liver.     

The parental resistance phenomenon and its genetic regulation

Lymphocytes of (CBA×M523)F₁ or (A×M523)F₁ mice, if transplanted into CBA or A recipients irradiated in a dose of 1000 rad, react to test antigens (sheep's red cells,Salmonella typhi Vi-antigen) by the formation of only 1/100–1/1000 of the number of antibody-forming cells formed by syngeneic recipients. An intermediate result was observed after transplantation of the same cells into irradiated M523 recipients. Conversely, lymphocytes of (A×CBA)F₁, (CBA×C57BL/6)F₁, or (A×A.CA)F₁ mice gave an equal immune response in syngeneic recipients and in CBA or A recipients. The ability of M523 lymphocytes or their hybrids to give an immune response to sheep's red cells did not differ from the immuno-reactivity of lymphocytes of other lines either in situ or in a syngeneic adoptive system. Hematopoietic stem cells from (CBA×M523)F₁ mice formed only 40–50% of the number of colonies in the CBA spleen as in the spleen of syngeneic recipients. It is concluded that the M523 mutation interferes with the proliferation and differentiation of hematopoietic cells and lymphocytes in nonsyngeneic irradiated recipients.N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. Research Laboratory of Experimental Biological Models, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR O. V. Baroyan.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 3, pp. 247–250, March, 1979.     

Physiological time series: distinguishing fractal noises from motions

Many physiological signals appear fractal, in having self-similarity over a large range of their power spectral densities. They are analogous to one of two classes of discretely sampled pure fractal time signals, fractional Gaussian noise (fGn) or fractional Brownian motion (fBm). The fGn series are the successive differences between elements of a fBm series; they are stationary and are completely characterized by two parameters, sigma2, the variance, and H, the Hurst coefficient. Such efficient characterization of physiological signals is valuable since H defines the autocorrelation and the fractal dimension of the time series. Estimation of H from Fourier analysis is inaccurate, so more robust methods are needed. Dispersional analysis (Disp) is good for noise signals while bridge detrended scaled windowed variance analysis (bdSWV) is good for motion signals. Signals whose slopes of their power spectral densities lie near the border between fGn and fBm are difficult to classify. A new method using signal summation conversion (SSC), wherein an fGn is converted to an fBm or an fBm to a summed fBm and bdSWV then applied, greatly improves the classification and the reliability of H, the estimates of H, for the times series. Applying these methods to laser-Doppler blood cell perfusion signals obtained from the brain cortex of anesthetized rats gave H of 0.24+/-0.02 (SD, n=8) and defined the signal as a fractional Brownian motion. The implication is that the flow signal is the summation (motion) of a set of local velocities from neighboring vessels that are negatively correlated, as if induced by local resistance fluctuations.     

Effect of Malnutrition on K+ Current in T Lymphocytes

Severe malnutrition in children is frequently associated with infectious diseases. Animal models have been useful for studying the effects of malnutrition. One of the immunosuppressive mechanisms of malnutrition is inhibition of the activation of T lymphocytes. The voltage-dependent K(V) potassium channels are vital for the activation of T lymphocytes. The blockade of K(V) channels inhibits the activation of T lymphocytes. Malnutrition could affect the suitable synthesis of K(V) channels in T lymphocytes, producing changes in the magnitude and/or dependency of the voltage of the K⁺ current. We reported a significant decrease in the K⁺ current and activation to a 20 mV more positive membrane potential in T lymphocytes of rats with severe malnutrition. These results indicate that the diminution in the K⁺ conductance by alteration of K(V) channels in severe malnutrition is one of the mechanisms that inhibit the activation of T lymphocytes.     

Immunocytochemical analysis of interferon-1β production by human monocytes

All-Union Research Institute of Highly Pure Biological Preparations, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. D. Belyakov). Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 9, pp. 278–280, September, 1991.     

Calpains and cathepsin D of the injured myocardium: Role of iodothyronines

Department of Biological Chemistry, Academician I. P. Pavlov Ryazan Medical Institute (Presented by Academician of the Russian Academy of Medical Sciences P. V. Sergeev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 12, pp. 596–598, December, 1992.     

Ability of thermo- and acid-stable serum serine protease inhibitor to inhibit mitogen-stimulated transformation of lymphocytes

The ability of a thermostable and acid-stable serine protease inhibitor from rabbit blood serum (TASPI) to inhibit the transformation of human peripheral blood lymphocytes stimulated by phytohemagglutinin (PHA) or concanavalin A (con A) was demonstrated. The degree of inhibition depends on the concentration of the inhibitor and its specific activity. The maximal degree of inhibition was 50–70%. TASPI has no cytotoxicity. Stronger inhibition of transformation is observed if TASPI is added to the culture 24 h after the addition of PHA. Data on the antiprotease activity of human blood serum, either native or inactivated under different conditions, are given. The results suggest that TASPI participates in the control of the biological activity of lymphoid tissue cells.Laboratory of Immunogenetics, Institute of Transplantation of Organs and Tissues, Ministry of Health of the USSR. Laboratory of Biochemistry and Pathochemistry of Vasoactive Polypeptides, Institute of Biological and Medical Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biology i Meditsiny, Vol. 85, No. 5, pp. 569–572, May, 1978.     

Summation or Axial Slab Average Intensity Projection of Abdominal Thin-section CT Datasets: Can They Substitute for the Primary Reconstruction from Raw Projection Data?

We hypothesized that that the summation or axial slab average intensity projection (AIP) techniques can substitute for the primary reconstruction (PR) from a raw projection data for abdominal applications. To compare with PR datasets (5-mm thick, 20% overlap) in 150 abdominal studies, corresponding summation and AIP datasets were calculated from 2-mm thick images (50% overlap). The root-mean-square error between PR and summation images was significantly greater than that between PR and AIP images (9.55 [median] vs. 7.12, p < 0.0001, Wilcoxon signed-ranks test). Four radiologists independently compared 2,000 test images (PR [as control], summation, or AIP) and their corresponding PR images to prove that the identicalness of summation or AIP images to PR images was not 1% less than the assessed identicalness of PR images to themselves (Wald-type test for clustered matched-pair data in a non-inferiority design). For each reader, both summation and AIP images were not inferior to PR images in terms of being rated identical to PR (p < 0.05). Although summation and AIP techniques produce images that differ from PR images, these differences are not easily perceived by radiologists. Thus, the summation or AIP techniques can substitute for PR for the primary interpretation of abdominal CT.     

Autoaggressive immunocompetent cells in mice in the late stages after irradiation

Lethally irradiated DBA/1 or (C57BL×DBA/1)F₁ mice were injected simultaneously with therapeutically effective doses of isologous bone marrow cells and syngeneic lymphocytes from intact mice (control) or from animals surviving different lengths of time after sublethal irradition. In the control the presence of lymphocytes in the mixed graft did not affect the survival rate of the recipients. Lymphocytes from mice surviving 6–12 months after irradiation in a dose of 600–700 R blocked the therapeutic effect of bone marrow (the killing effect). The intensity of the killing effect depended on the number of lymphocytes transplanted and the number of bone marrow cells in the graft. No killing effect was found if mice surviving 1 month after irradiation were used as donors of the lymphocytes. The results are regarded as evidence of autosensitization of the animal in the late stages after irradiation.Laboratory of Radiation Immunology and Microbiology, Central Roentgeno-Radiological Research Institute, Ministry of Health of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. I. Ioffe.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 4, pp. 454–457, April, 1978.     

Spatial summation by simple cells in the striate cortex of the cat

Summary Spatial summation has been studied in simple cells of the cat's visual cortex by examining the responses to pairs of lines. One line was placed in an ON region of the receptive field; the other was placed in an OFF region. When the luminances of the lines were modulated in anti-phase, the excitatory responses to the individual lines were almost synchronous. A simple cell's overt response to the composite stimulus was usually greater than the sum of the overt responses to the two components. The result could be explained by supposing that the underlying response was the linear sum of the excitatory signals but that an overt response occurred only when the underlying response exceeded a fixed threshold value. This was true even of simple cells which exhibited non-linearities of spatial summation, as judged from the waveforms of their responses to moving sinusoidal gratings. When the two lines were modulated in phase, the excitatory responses occurred in different halves of the temporal cycle. Some cells summed antagonistic signals linearly. The waveforms of their responses to moving sinusoidal gratings also implied linear spatial summation. However, other cells whose responses to moving gratings implied linearity of summation did not, in fact, sum antagonistic signals linearly. The excitatory responses evoked in a receptive field region were weaker than the inhibitory responses that could be evoked in the same region. The remaining cells did not sum antagonistic signals linearly. There was imperfect cancellation, resulting in the generation of ON-OFF response components. The excitatory responses evoked in a receptive field region were stronger than the inhibitory responses that could be evoked in the same region. These cells gave responses to sinusoidal gratings that did imply non-linear spatial summation.