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One of the urgent problems of nursing premature babies is the timely prediction, diagnosis and treatment of anemia, the frequency of which reaches 90%. Of particular importance is the study of reticulocytic blood parameters in deep-premature newborns, since the correct assessment of hemograms is crucial in the management of this category of children. To determine the characteristics of red blood cells and reticulocyte parameters of venous blood hemogram in premature newborns 24-32 weeks of gestation in the dynamics of the neonatal period. 111 newborns were examined at 24-32 weeks of gestation in the early neonatal period (on day 3-7) and at the age of 1 month of life. Along with standard diagnostic procedures, in accordance with current clinical recommendations and standards, 28 parameters of erythrocyte and reticulocyte hemogram parameters were determined for children. Venous blood was examined using an automatic hematological analyzer ADVIA 2120i, Siemens, USA. In deep-premature newborns in the early neonatal period, there is a high activity of erythropoiesis, respectively, the severity of respiratory and metabolic disorders with rejuvenation of reticulocytic subpopulations. Negative values of Delta hemoglobin were found against the background of a decrease in the average amount of hemoglobin in reticulocytes in children 24-27 weeks of gestation, which characterizes the lowest values of iron availability for erythropoiesis in this category of newborns. It is shown that a decrease in reticulocyte counts and normochromia in all examined newborns by the age of one month are accompanied by high levels of immature reticulocyte fraction, while a third of children still have limited iron availability for erythropoiesis.

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OBJECTIVE: To study dynamics of the indicators of the hormonal and psychological status as well as psychological features of significance for the sportive performance under conditions of rehabilitative treatment during training and post-training periods in the child athlete engaged in rhythmic gymnastics. MATERIAL AND METHODS: The study included 42 child athletes at the age from 8 to 15 years engaged in rhythmic gymnastics. The children of the study group (group 1, n=17) received the combined restorative treatment under conditions of regular training while those comprising group 2 group (n=25) were given a similar treatment in the absence of the training load. All athletes underwent clinical and laboratory examination before and after the treatment for the assessment of their psychological status. RESULTS: The study has demonstrated that additional physical activities were responsible for the development of negative changes in the hormonal and psychological spheres of the child athletes. As a result, they experienced the impairment of certain qualities significant for their sportive performance. CONCLUSION: The rehabilitative measures during different periods of the training cycle promote normalization of all parameters of the hormonal, psychological, and physical status of the child athletes; moreover, they improve the adaptive capacity of the children.

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Our previous work has correlated permanent alterations in the rat neurosecretory machinery with epileptogenesis. Such findings highlighted the need for a greater understanding of the molecular mechanisms underlying epilepsy so that novel therapeutic regimens can be designed. To this end, we examined kindling in transgenic mice with a defined reduction of a key element of the neurosecretory machinery: the v-SNARE (vesicle-bound SNAP [soluble NSF attachment protein] receptor), synaptobrevin/vesicle-associated membrane protein 2 (VAMP2). Initial analysis of biochemical markers, which previously displayed kindling-dependent alterations in rat hippocampal synaptosomes, showed similar trends in both wild-type and VAMP2(+/-) mice, demonstrating that kindled rat and mouse models are comparable. This report focuses on the effects that a ~50% reduction of synaptosomal VAMP2 has on the progression of electrical kindling and on glutamate release in hippocampal subregions. Our studies show that epileptogenesis is dramatically attenuated in VAMP2(+/-) mice, requiring both higher current and more stimulations to reach a fully kindled state (two successive Racine stage 5 seizures). Progression through the five identifiable Racine stages was slower and more variable in the VAMP2(+/-) animals compared with the almost linear progression seen in wild-type littermates. Consistent with the expected effects of reducing a major neuronal v-SNARE, glutamate-selective, microelectrode array (MEA) measurements in specific hippocampal subregions of VAMP2(+/-) mice showed significant reductions in potassium-evoked glutamate release. Taken together these studies demonstrate that manipulating the levels of the neurosecretory machinery not only affects neurotransmitter release but also mitigates kindling-induced epileptogenesis.

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The characteristics of somatic health of children's home inmates with the perinatal affections of central nervous system of slight and average severity are analyzed. It is established that these children are characterized by more frequent morbidity and formation of chronic pathology in earlier periods as compared with their coevals from families. They have significantly higher rate of background pathology and more numbers of health disorders falling to 1 child. This testifies to significant impact on the health state of early age children of both perinatal affections of central nervous system and educational conditions.

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Kindling is a model of complex partial epilepsy wherein periodic application of an initially subconvulsive stimulus leads to first limbic and then generalized tonic-clonic seizures. Several laboratories have reported that augmented neurotransmitter release of l-glutamate is associated with the chronically kindled state. Neurotransmitter release requires membrane proteins called SNAREs, which form transmembrane complexes that participate in vesicle docking and are required for membrane fusion. We show here that kindling by entorhinal stimulation is associated with an accumulation of 7S SNARE complexes in the ipsilateral hippocampus. This increase of 7S SNARE complexes appears to begin early in the kindling process, achieves a peak with full kindling, and remains at this level for at least a month following cessation of further kindling stimuli. The increase is focal and permanently limited to the ipsilateral hippocampus despite progression to generalized electrographic and behavioral seizures. It is not seen in animals that receive electroconvulsive seizures, suggesting it is related to the kindling process itself. The duration and focality of increased 7S SNARE complexes with entorhinal kindling suggest that this is an altered molecular process associated with epileptogenesis.

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Our understanding of the molecular mechanisms of membrane trafficking advanced at a rapid rate during the 1990s. As one of the initial protein components of the trafficking machinery to be identified, N-ethylmaleimide sensitive factor (NSF) has served as a reference point in many of these recent studies. This hexameric ATPase is essential for most of the membrane-trafficking events in a cell. Initially, due to its ATPase activity, NSF was thought to be the motor that drove membrane fusion. Subsequent studies have shown that NSF actually plays the role of a chaperone by activating SNAP receptor proteins (SNAREs) so that they can participate in membrane fusion. In this review we will examine the initial characterization of NSF, its role in membrane fusion events, and what new structural information can tell us about NSF's mechanism of action.

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Critical to SNARE protein function in neurotransmission are the accessory proteins, soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein (SNAP), and NSF, that play a role in activation of the SNAREs for membrane fusion. In this report, we demonstrate the depolarization-induced, calcium-dependent phosphorylation of NSF in rat synaptosomes. Phosphorylation of NSF is coincident with neurotransmitter release and requires an influx of external calcium. Phosphoamino acid analysis of the radiolabeled NSF indicates a role for a serine/threonine-specific kinase. Synaptosomal phosphorylation of NSF is stimulated by phorbol esters and is inhibited by staurosporine, chelerythrine, bisindolylmaleimide I, calphostin C, and Ro31-8220 but not the calmodulin kinase II inhibitor, Kn-93, suggesting a role for protein kinase C (PKC). Indeed, NSF is phosphorylated by PKC in vitro at Ser-237 of the catalytic D1 domain. Mutation of this residue to glutamic acid or to alanine eliminates in vitro phosphorylation. Molecular modeling studies suggest that Ser-237 is adjacent to an inter-subunit interface at a position where its phosphorylation could affect NSF activity. Consistently, mutation of Ser-237 to Glu, to mimic phosphorylation, results in a hexameric form of NSF that does not bind to SNAP-SNARE complexes, whereas the S237A mutant does form complex. These data suggest a negative regulatory role for PKC phosphorylation of NSF.

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N-Ethylmaleimide-sensitive factor (NSF) has been shown to be involved in numerous intracellular membrane fusion events of both the regulated and constitutive secretory pathways. Sequence analysis indicates that the NSF subunit contains two nucleotide-binding sites, both with the classical Walker A and B motifs. In this report, we examine the nucleotide binding properties of NSF. The homotrimer contains three high affinity ATP-binding sites with Kd = 30-40 nM for ATP and Kd = 2 microM for ADP. This class of binding sites did not bind AMP, adenine, or GTP. A second class of lower affinity nucleotide binding sites with a Kd = 15-20 microM was also detected. Using various mutant forms of NSF, the high affinity nucleotide-binding sites were localized to the D2 domains and the low affinity sites were localized to the D1 domains. Functionally it is these lower affinity sites in D1 that are crucial for NSF activity. Nucleotide concentration greatly affected the ability of NSF to interact with alpha-SNAP.SNARE (soluble NSF attachment protein-SNAP receptor) complex, suggesting that only when the D1 domain ATP-binding sites are occupied does NSF bind to the alpha-SNAP.SNARE complex.

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A sensitive assay which examines the effects of ATP level on the overall activity of a cell-free translation system in a protein synthesis is described. The translational activity of cell-free system was measured in terms of a rate of protein synthesis directed by the 'test' template. The test template encodes a photoluminescent protein, obelin accumulation was determined from the kinetic curves of obelin. The rate of obelin mRNA translation. Time-dependent nucleotide level measurements were conducted throughout the translation processes. It has been shown that the rate of translation decreases exponentially with the decrease of the ATP level. This fall in the overall translation rate is due in part to the mRNA becoming inactive in the translation process. This is not caused by degradation, this mRNA can be restored for translation in a fresh cell-free system by phenol treatment. The reported results provide evidence that the level of ATP unambiguously determines the translational activity of the system.

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The rat olfactory epithelium contains a specific water-soluble 45-kDa protein. This protein is recognized by anti-peptide antibodies which react with alpha-subunits of the known G-proteins. The 45-kDa protein has been isolated using DEAE-chromatography and gel-exclusion chromatography. The content of 45-kDa protein is about 2% of the total soluble proteins of the olfactory mucosa and it is located at the mucociliary surface. According to photo-affinity labeling, the 45-kDa protein possesses a high affinity to GTP and exhibits low GTP hydrolytic activity. The functions of the 45-kDa protein are discussed.

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Rat olfactory epithelium and ciliar cytosol of olfactory cells contained the water-soluble 45 kDa protein which was revealed by antibodies against a peptide fragment of the alpha-subunits common to the G-proteins. No analogous proteins were found in other rat tissues. According to the photo-affinity labeling, the 45 kDa protein possessed a high affinity to GTP; it also exhibited a low GTP hydrolytic activity.

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The pathological material from 77 surgical patients with purulent infections was assayed microbiologically and the properties of the pathogens were investigated. Multiple antibiotic resistance of the microflora monocultures and associations was shown. The aminoglycoside antibiotics and first of all gentamicin were the most effective.

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The study of the characteristics of the phagocytic activity of peripheral blood neutrophils (the activity and intensity of phagocytosis, the index of its completeness) in the sensitized organism in experimental keratoconjunctivitis caused by Staphylococcus aureus and Escherichia coli has revealed a decrease in the phagocytic function of neutrophils. Still more pronounced suppression of the ingestive and digestive activity of leukocytes has been observed in cases of the combined action of bacterial allergens and benzylpenicillin potassium, which probably accounts for the ineffectiveness of the penicillin treatment of bacterial keratoconjunctivitis.

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The influence of low-frequency ultrasound on the chemotactic, ingestive and digestive activity of peritoneal macrophages in rats was studied. The intraoperative treatment of the peritoneum with ultrasound enhanced chemotactic activity 3.3-fold in comparison with that in the control animals. The digestive function of peritoneal macrophages considerably increased, the stimulation of their ingestive capacity also occurred. The activation of the phagocytic function of macrophages was observed within 7 days after a single sonar treatment. The authors believe that the stimulation of the macrophage system is probably one of the mechanisms of the sanative action of ultrasound which is used at present in purulent surgery.

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Experiments carried out in rats demonstrated that a burn of degree III of 20% of the body surface disturbs considerably the process of lung clearance from bacterial dissemination (5 million bodies of Pseudomonas pyocyanea). Not only decreased but even negative clearance may be observed indicating multiplication of the bacteria in pulmonary tissues for the first 3 days after burn, and intratracheal infection of the animals. Reduced general antibacterial resistance as a result of burn facilitates rapid penetration of P. pyocyanea into the lymph nodes, blood, kidneys, liver, spleen where it is found 6 hours after infection.

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