Hypertrophic synapses as a factor of formation of persistent pathological centers in the brain in the late postresuscitation period

Clinical death was modelled on albino rats. Synapses in the molecular layer of the cerebral sensorimotor cortex were investigated 1, 2, 3, 4, 5, 6, 7, 8, and 9 months postresuscitation. The total density of synapses peaked and the number of hypertrophic and perforated contacts increased 4, 7, and 9 months after resuscitation. The role of increased number of hypertrophic and perforated contacts in the pathogenesis of postresuscitation encephalopathy is discussed. Translated fromByuleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129 No. 5, pp. 532–535, May, 2000     

Development of synapses as the basis of their involution

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N ^o 8, pp. 214–217, August, 1993     

New data on the fine structural organization of the subsynaptic zone of the nerve cell

The fine structural organization of the subsynaptic zone of the nerve cell was studied by electron microscopy. This zone of the neuron was shown to be directly connected with special intracellular organelles or microtubules. Their peripheral ends, expanded like funnels, are in close contact with the postsynaptic membrane and apparently merge with its inner osmiophilic layer. These observations definitely show that direct structurally organized connections exist between the synaptic region of the neuron and the deep layers of its cytoplasm. A hypothesis to explain the functional role of these connections is put forward.Laboratory of Development of the Peripheral Nervous System, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 502–505, October, 1977.     

Bradykinin as a factor regulating synaptic input toHelix pomatia neurons

The effect of bradykinin on spontaneous unit activity was studied in the subesophageal ganglion ofHelix pomatia by microiontophoresis. Bradykinin was shown not only to facilitate unit responses to synaptic activation, but also to prolonged action potential generation evoked by this activation. The effects of bradykinin were observed in experiments carried out during the spring.Laboratory of Emotions and Emotional Stress, P. K. Anokhin Institute of Normal Physiology, and Laboratory of Pharmacology of the Nervous System, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 7, pp. 48–50, July, 1979.     

Syngeneity as a factor in cooperation between T- and B-lymphocytes

Effectiveness of cooperation between (CBA x C57BL/6)F₁ thymocytes and CBA bone-marrow cells in the immune response to sheep's red cells was compared with syngeneic combinations of the same cells in culturein vivo. The selectiveness of cooperation between T- and B-lymphocytes of different origin also was investigated in incomplete (CBA x C57BL/6)F₁CBA chimeras obtained with the aid of cyclophosphamide, in which the donors were primed with sheep's red cells and the recipients were either intact or were tolerant to that antigen. F₁ T-cells were shown to cooperate with CBA B-cells 10–50 times less effectively than with syngeneic B-cells. It is postulated that the similar antigenic structure of the cell membrane of T- and B-lymphocytes, acting in conjunction with their physical contact, increases the effectiveness of action of the T-mediator on the B-cellLaboratory of Immunological Tolerance, N. F. Gamaleya Institute of Epidemiology and Microbiology, 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. 81, No. 3, pp. 325–327, March, 1976.     

Lactic acid as a factor in changes of vascular reactivity

Results showing that contractile responses of isolated vascular segments to electrical stimulation are replaced by relaxation if the preparations are contained in a solution with lactic acid are described. Ability to contract is not completely lost under these circumstances but it is manifested only during very strong stimulation. The changes in the character of response to electrical stimulation are connected both with changes in the pH of the solution and with the specific action of the lactic acid.Laboratory of Physiology and Pathophysiology of the Circulation, A. L. Myasnikov Institute of Cardiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR E. I. Chazov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 923–926, August, 1976.     

Homologous antitissue antibodies as a factor inhibiting the development of malignant tumors

Experiments with transplanted and induced tumors showed that the physiological system of autoimmunity (homologous antitissue antibodies) can be used to increase resistance of the host to growth of malignant neoplasms. A method is developed for obtaining a globulin preparation containing normal antitissue antibodies in high titer.Laboratory of Pathological Physiology, P. A. Gertsen Moscow Oncologic Research Institute. Institute of Biophysics, Minstry of Health of the USSR, Moscow. (Presented by Academician N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 468–471, October, 1977.     

Proliferative activity of tumor cells as a prognostic factor in breast cancer

The proliferative activity of 92 breast carcinomas was studied. Statistically significant correlations between the level of proliferative activity and degree of differentiation of tumor cells and nuclear grade were found. Statistically reliable differences in proliferative activity were revealed in the groups of patients under and over 50 years. These facts show that proliferative activity can be used as an individual factor for predicting the aggressiveness of the neoplastic process in patients with breast cancer. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 215–217, August, 1995     

Plasticity and stability of synapse architectonics of the cerebral cortex

Changes in the interneuronal contacts and recombinant changes in the synapse architectonics play an important role in its plasticity. Along with the reorganization of the synapse architectonics, these changes are attended by an increase or decrease in the number of interneuronal contacts. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny Vol., 121, N ^o 3, pp. 321–323, March, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Accumulation of factor stimulating glial proliferation in aging mammalian brain

Extract from the brain of young mice produced weak cytoproliferative effect on cultured glial cells, while brain extract from old mice 3–4- and 30–60-fold stimulated glial proliferation in primary and passaged cell cultures, respectively. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 3, pp. 317–320, March, 2000     

The resistance of cutaneous feline polymodal C-fiber units to tetrodotoxin as revealed by mechanical and thermal stimulation

Mechanical and thermal excitability of cutaneous feline polymodal C-fiber units is maintained under the action of subcutaneous tetrodotoxin injected in concentrations suppressing the mechanosensitivy of A_β-units. A number of features of inhibition and excitation of C-fiber polymodal sensory units can be explained by existence of tetrodotoxinresistant Na channels in their termination. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 10, pp. 369–371, October, 1997     

Fibronectin as a compensating factor in the natural cytotoxicity system in interferon-dependent immunodeficiency

The cytotoxicity of natural killer cells (NK) against³H-uridine-labeled target cells (TC, human erythromyeloleukosis cells K-562) and the intensity of conjugate formation in the NK:TC system in the presence of γ-interferon, C-reactive protein, and human fibronectin are studiedin vitro in 14 patients with multiple sclerosis. It is shown that γ-interferon and C-reactive protein decrease the cytotoxic activity of NK with a simultaneous stimulation of conjugate formation in the NK:TC system. The correlation between the studied parameters becomes weaker. Human fibronectin induces collateral changes in the activity of NK and in the number of effector:target conjugates formed in the natural cytotoxicity reaction. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 67–70, July, 1994     

Escherichia coli strain M17: Analysis of adhesive phenotype as a factor of host colonization and/or pathogenicity

FimH adhesins M₁L and M₁H are differently adapted to colonization of primary normal and secondary pathological niches of humanE. coli. The M^L phenotype is typical and optimal for intestinalE. coli, while M^H phenotype predominates among pathogenic strains and is undersirable for the eubiotic intestinalE. coli strain M17. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 424–428, April, 1999     

Oxidative stress in keratinocytes as an etiopathogenetic factor of psoriasis

A new etiopathogenetic concept of psoriasis is proposed, which considers psoriasis as a typical inflammatory process characterized by increased antioxidant activity and overexpression of apoptotic receptors. Under these conditions, hyperstimulation of germinative layer cells proliferation dramatically accelerates kerationcyte passage towards apoptotic effect of atmospheric oxygen and its reactive species dooming to death cells with enhanced expression of apoptotic receptors. Oxidative stress of nondifferentiated kerationcytes triggers the formation of defective horny layer, the key mechanism of psoriasis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 4, pp. 364–369, April, 2000     

Month of birth and prevalence of atopic dermatitis in schoolchildren: Dry skin in early infancy as a possible etiologic factor

BACKGROUND: Month of birth has been shown to affect later development of allergic diseases. OBJECTIVE: We sought to evaluate the relationship between month of birth and the prevalence of atopic dermatitis (AD) in a large-scale general population of schoolchildren and to elucidate the possible mechanism for this relationship. METHODS: Questionnaire data on the prevalence of allergic diseases were obtained for 33,725 schoolchildren aged 7 to 15 years. In a separate study the water-holding capacity of "uninvolved" skin was compared for children with and without AD. RESULTS: We found striking differences in the prevalence of AD according to the month of birth (chi2 = 34.9, P <.0001). Overall, those born in autumn showed the highest (7.5%), and those born in spring showed the lowest (5.5%), prevalence of AD. There was little or no such tendency for the prevalence of bronchial asthma (chi2 = 17.2, P =.103) and allergic rhinitis (chi2 = 24, P =.01). We found no statistical variation across birth month in the ratio of AD with no other allergic disease/total AD, indicating that this deviation was observed whatever the allergic predisposition of the subjects. In a separate study a significantly lower water-holding capacity of uninvolved skin was observed in children with AD even from early infancy. CONCLUSION: These findings lead us to speculate that the climate in early infancy affects the skin condition and that those born in autumn have dry skin in early infancy, which may ultimately result in a higher prevalence of AD among young schoolchildren. This might be at least one of the "nonallergic" etiologic factors of this complex disease.     

Physiological role of desensitized cholinoceptors in skeletal muscle

The effect of desensitized cholinoceptors on the time course of end-plate currents was evaluated in frog skeletal muscle at a high (physiological) level of acetylcholine secretion in the presence of active acetylcholinesterase, with two-electrode recording of the membrane potential. When the number of cholinoceptors was small so that they did not appreciably affect the amplitude of end-plate currents or the parameters of onequantum responses (miniature currents), the decay of multiquantum currents was significantly accelerated. Moreover, the presence of cholinoceptors drastically reduced the ability of acetylcholinesterase inhibitors to prolong the decay of end-plate currents. It is suggested that desensitized cholinoceptors in a synapse with a physiological level of acetylcholine secretion and active acetylcholinesterase may bind free acetylcholine with high affinity and thus supplement the well-known physiological role of acetylcholinesterase in limiting the reactivation of postsynaptic membrane cholinoceptors Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No. 6, pp. 578–581, June, 1995 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Peculiarities of external respiration as a marker of activity of cell respiratory enzymes in rat brain

Rats with catatonic freezing are characterized by low motor and explorative activity in the open field test and specific pattern of external respiration, so-called strenuous respiration, which is accompanied by a higher activity of the respiratory enzymes succinate dehydrogenase and NADH dehydrogenase in the hippocampus and motor cortex. No dependencies on the brain structure and animal age are noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 138–140, August, 1997     

Morphometric peculiarities of the brain in two-month-old rats as a function of body weight at the age of one month

The brain from 2-month-old rats up to the age of 1 month was studied in litters of different size: 9–13 (control) and 4–6 (reduced) animals. In animals from reduced litters the absolute weight of the brain surpassed that of controls. The maximum brain weight is characteristic of animals from reduced litters with maximum body weight at the age of one month, while the minimal brain mass is found in controls with the minimal body weight. There are no differences in the cortical thickness and neuron density in layers II and V between these two groups. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 115–117, July, 1997     

Role of fibroblasts as the principal factor in differentiation of the epidermis

The role of fibroblasts in the differentiation of the epidermis and its relationships with other somatic cells, specifically, keratinocytes, are studied using a skin equivalent formed from various types of fibroblasts separated from thoracic skin of a healthy donor, apparently healthy skin sites and plaques from a patient with psoriasis, keloids and upper eyelid skin of a normal subject, and keratinocytes separated from the umbilical skin of a newborn. Fibroblasts are shown to be active participants in the differentiation and formation of epidermis specificity. Various types of fibroblasts form a histologically different skin equivalent possessing the specific properties of the epidermis of the skin sites from which they were isolated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 80–84, January, 1996 Presented by R. V. Petrov, Member of the Russian Academy of Medical Sciences     

Structural basis of changes in deformation of synaptic contacts of the sensorimotor and cerebellar cortex in health and acute ischemia

Paramembranous specialized formations of the synaptic cytoskeleton — dense projections and postsynaptic condensation of axospinous synapses of the molecular layer of white rat sensorimotor and cerebellar cortex — in health and acute total ischemia are studied by selective contrast staining with phosphotungstic acid. A direct relationship is revealed between the pattern and degree of deformation of the contact plane, on the one hand, and the postsynaptic condensation and ratio of the volumes of pre- and postsynaptic accumulations of paramembranous filaments, on the other. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 443–445, April, 1995 Presented by L. V. Poluektov, Member of the Russian Academy of Medical Sciences