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We report here studies of the consequences of lesioning of the dorsal hippocampus of DBA/C57 F1 mice during training in a complex multiple-choice maze in conditions of free selection. Hippocampectomized (HPC) mice were found to be able to form a four-component food-procuring skill in cyclic form. The main features were linked with the nature of the execution of exploratory activity, behavioral effectiveness, and the extinction of errors. While in controls each of these processes followed a common exponential law, each component in HPC mice had independent dynamics. The main hippocampectomy-associated effects at the stabilization stage consisted not only of a sharp decrease in the time during which a high level of motivation was maintained, but also of difficulty in transferring from unorganized behavior to organized behavior. It is suggested that the hippocampus operates not so much in learning and memory as in the organization of the operative dominant supporting the stability of attention on execution of an acquired skill

The damage of dorsal hippocampus in mice F1 from DBA/2J and C57BL/6J on the learning in conditions of free choice in a complex multialternative maze was studied. It was revealed that the HPC-mice were able to form a 4-links food-getting habit in the cyclic form. The main differences affected the conjugation of the investigate activity, behavioral efficiency and inhibition of mistakes. While these processes developed by the same exponential types in control, this conjugation were absent in HPC-mice. The main defects were found in stage of habit stabilization: motivational state stability reduced sharply and duration of transition from disorganization to organizing behavior increased. It is supposed that the hippocampus involved in learning and memory indirectly because its main role is organization of the dominant state providing the stability of attention for habit realization.

The effects of repeated opilong injections in a dose of 50 microg/kg/day on subsequent learning of Wistar rats have been studied. The substance caused significant anxiolytic and analgesic effects, as the majority of animals could be learned (90% against 40% in control group) despite of painful stimulus preceding to education. Opilong in a small dose displaced a relation of excitatory-inhibit processes to significant prevalence of excitation although the substance was already absent in an organism for a long time. Raised peripheral sensitivity in all rats, provoked by opilong, correlated with CNS hyper excitability, expressed in stressful, neurotic psychoemotional reactions and in the form of active avoidance. The biochemical blood analysis in opilong-induced rats demonstrated the attributes of prethrombosis in the form of fibrinolysis depression and hypercoagulation. A view is expressed, that the neuromediator brain systems can be the basic point of opilong action, that are responsible for the excitatory-inhibit conditions of CNS functioning referred on maintenance of conditioned field stability.

Transplantation of erythroid and bone marrow cells to irradiated mice stimulated exogenous colony formation. Pretreatment of erythroid cells with specific rabbit antiserum to erythroblasts abolished this effect. The reverse transcriptase polymerase chain reaction revealed the presence of mRNA for interleukin-1α, interleukin-1β, interleukin-3, interleukin-6, and granulocyte-macrophage colony-stimulating factor in erythroid cells. Granulocyte-macrophage colony-stimulating factor was found in the conditioned medium from erythroid cells. Thus, erythroid cells stimulated colony-forming activity of bone marrow cells, which was probably mediated via cytokine synthesis (e.g., granulocyte-macrophage colony-stimulating factor).

Effects of repeated piracetam (PIR) injections in a dose of 40 and 250 mg/kg/day on the learning in Water rats were studied. It has been found that character of the effects depends on typological features of the animals. Rats with strong predominance of excitation (choleric type) showed low sensitivity to PIR. Small dose of PIR provoked clear negative effect in rats with relative balance of the basic nervous processes: excitation and inhibition (sanguine and phlegmatic types). Despite of expressed activation of associative process, it complicated integrative activity. Small dose of PIR showed anxiolytic and psycho-stimulant actions only in initially unlearned rats characterized by high level of fear. Large dose of PIR had negative influence on the learning process in all animals, irrespective of typological features. Thus, the results of this study allow to suppose that the individual sensitivity of an animal to action of a pharmacological medication is caused by morpho-functional and neurochemical intraspecific heterogeneity.

Moxifloxacin efficacy was studied in a prospective open controlled incomparable surveillance of 22 patients at the age of 24 to 78 years (the average of 56.6 +/- 15.9 years old) with extended secondary peritonitis that developed before the hospitalization or not later than 48 hours after the hospitalization. Moxifloxacin (Avelox) was used in a dose of 400 mg every 24 hours at first intravenously as infusions and then orally in the same dose. The abdominal infection was severe (APACHE II of 6 to 12, the average of 8.0 +/- 2.2), in 6 (27.3%) patients signs of severe sepsis with polyorganic insufficiency were observed. The intravenous therapy was used for 3 to 7 days (the average of 3.91 +/- 0.92 days) and the oral therapy was used for 2 to 7 days (the average of 4.50 + 1.37 days). The total time of the treatment was 7 to 12 days (the average of 8.45 +/- 1.53 days). The recovery was recorded in 20 out of the 22 patients (90.9%), disappearance of the main signs of peritonitis being observed within 3-5 days of the treatment. Before the treatment 34 microbial strains were isolated. The most frequent pathogens were E.coli (35.4%) and Enterococcus faecalis (20.6%). In the etiological structure of the community-acquired peritonitis gramnegative enterobacteria prevailed (65%). All the isolates (except 1 strain of E. faecalis) were susceptible to moxifloxacin. The pathogen eradication was stated in 17 out of 18 patients (94.4%). Moderate adverse reactions were observed in 3 patients. Moxifloxacin evidently showed high clinical and bacteriological efficacies in the hospitalized patients with complicated intraabdominal infection including severe abdominal sepsis with the syndrome of polyorganic insufficiency. It can be used for monotherapy of patients with secondary extended peritonitis.

The leading pathogens of severe infections in intensive care units were the following: respiratory tract infections--bacteria of the famility of Enterobacteriaceae (33.8%), Pseudomonas spp. (24.9%), Acinetobacter spp. (18.1%), Staphylococcus aureus (16.0%), blood flow infections--coagulase negative staphylococci (33.6%), S. aureus (26.1%), Enterobacteriaceae (17.6%), wound infections--Enterobacteriaceae (35.7%), coagulase negative staphyloccocci (17.8%), Pseudomonas spp. (14.3%). As for various species of Enterobacteriaceae, susceptibility was preserved in 91-100% of the isolates to meropenem, in 72-100% to cefoperazone/sulbactam, in 51-65% to cefepime, in 72-86% to amikacin, and in less than 50% to cephalosporins and fluoroquinolones. As for P.aeruginosa, 28% of the isolates was resistant to all the antibacterials, except polymyxin. The highest susceptibility to cefoperazone/sulbactam and meropenem was revealed in the isolates of Acinetobacter baumannii. Oxacillin resistance was detected in 64.9% of the S.aureus isolates. The oxacillin resistance as a rule was associated with resistance to macrolides, aminoglycosides and fluoroquinolones. As for coagulase negative staphylococci, oxacillin resistance was stated in 75.6% of the isolates. All the isolates of the Staphylococcus spp. preserved their susceptibility to vancomycin and linezolid.

During the 6-year observation period from 1998 to 2003 in Moscow there was recorded in 2000-2001 a decrease in the emergence of Streptococcos pneumoniae resistance to many antibacterials, while during the following years the respective index increased. The above dynamics in the resistance emergence was likely due to a decrease in the use of antibiotics in 1998-1999. In 2003 the rate of resistance to penicillin was 18.6%, 0.4 and 2.1% of the isolates were resistant to amoxicillin and cefotaxime respectively, the rate of resistance to erythromycin reached 19%, 65.4% of the resistant strains showed M phenotype. High rates of resistance were as well observed with respect to tetracycline (40.1%), co-trimoxazole (29.1%) and chloramphenicol (18.6%). Resistance to levofloxacin and moxifloxacin was detected only in rare strains.

Transplantation of erythroid and bone marrow cells to irradiated mice stimulated exogenous colony formation. Pretreatment of erythroid cells with specific rabbit antiserum to erythroblasts abolished this effect. The reverse transcriptase polymerase chain reaction revealed the presence of mRNA for interleukin-1alpha, interleukin-1beta, interleukin-3, interleukin-6, and granulocyte-macrophage colony-stimulating factor in erythroid cells. Granulocyte-macrophage colony-stimulating factor was found in the conditioned medium from erythroid cells. Thus, erythroid cells stimulated colony-forming activity of bone marrow cells, which was probably mediated via cytokine synthesis (e.g., granulocyte-macrophage colony-stimulating factor).

The action of mupirocin as a nasal ointment (Bactroban) was studied on intranasal carriers of the hospital staphylococcal strains. The study included 37 medical workers from different and mainly problem units of the large general hospital. The tolerability of the ointment was good. After the Bactroban use no complications of the patients were recorded. The efficacy of Bacroban by the microbiological criteria in total amounted to 100 per cent. The eradication of methicillin resistant Staphylococcus aureus (MRSA) was observed in 93 per cent of the cases. A decrease of the level of the nasal passages dissemination by MRSA and methicillin resistant coagulase-negative staphylococci (MRSC) up to such low titers as 100 and 90 per cent was stated. No difference in the action of Bactroban on MRSA, MSSA and MRSC was noted. The bacteriological monitoring for 3 to 4 months revealed a change of the staphylococcal strains in 94 per cent of the cases, recolonization by the same staphylococcal strain in 19 per cent, recolonization by some another staphylococcal strains in 33 per cent and no recolonization in 14 per cent. A stable decrease of staphylococcal strains was possible with simultaneous Bactroban sanitation of all the bacterial carriers of the hospital or its isolated unit.

Erythroid nuclear cells have been shown to exert regulatory effects on immunopoiesis. We have reported that some of these influences might be mediated via soluble factors secreted by nuclear erythroid cells. In this report we describe our estimate of the cytokine gene expression in cells isolated from individual erythroid colonies by Reverse transcription-Polymerase chain reaction. We found in erythroid cells, originated from the bone marrow precursors obtained from phenylhydrazine-treated mouse, the expression of the following cytokine genes: IL-1 alpha and IL-1 beta, IL-4, IL-6, GM-CSF, gamma-IFN and TGF-beta. In contrast, the erythroid cells derived from newborn mouse spleen precursor cells expressed IL-1 alpha, IL-1 beta, IL-4, IL-6 and GM-CSF mRNAs but not gamma-IFN and TGF-beta mRNAs. No detectable levels of IL-2, IL-3 and IL-5 mRNAs were expressed in nuclear erythroid cells. These data provide evidence of the expression of mRNAs coding in the set of immunoregulatory cytokines in immature erythroid progenitor cells in mouse.

Fifteen patients with severe hospital infections such as postoperative pneumonia or intraabdominal sepsis were treated with ofloxacin in a dose of 400 mg once a day for 7 to 14 days (11 days at the average). The drug was administered intravenously for the first 3-5 days and then orally till the end of the treatment course. The clinical effect was observed in 14 patients (93 per cent) and the positive bacteriological effect was stated in 11 out of 13 patients (85 per cent). Before the treatment 18 microbial cultures were isolated from the patients. 94 per cent of them was susceptible to ofloxacin. The isolates of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the most frequent. The treatment resulted in the eradication of 15 cultures (83 per cent). The adverse reactions were observed in 3 patients but only in 1 of them they were for certain due to the drug use. All the adverse reactions were insignificant or moderate and did not require the treatment discontinuation. The trials showed that ofloxacin was a highly efficient agent useful in the empirical monotherapy of patients with severe hospital infection.

The efficacy of cefpirome was estimated in the treatment of 12 patients with severe hospital infection in the Municipal Hospital No. 7. The positive clinical effect at the background of the cefpirome use was recorded in 11 patients. The eradication of the primary pathogens was stated in 10 patients. 116 isolates were tested for their susceptibility to cefpirome. 92 per cent of the isolates from outpatients and 79 per cent of the isolates from inpatients proved to be susceptible to the antibiotic. The results of the cefpirome use in the treatment of patients with various infections in 6 hospitals of Moscow were analyzed. The positive clinical effect was observed in 103 out of 111 patients (93 per cent). The eradication of the primary pathogens was recorded in 90 out of 102 patients (88 per cent). In the treatment of the lower respiratory tract infection, urinary tract infection and surgical infection the positive clinical results were stated in 91, 95 and 96 per cent of the cases respectively. Insignificant or moderate side effects of the drug were observed in 17 patients. Discontinuation of the drug use because of the side effects was required in 2 of them. The results showed that the use of cefpirome in the monotherapy of various severe hospital infections was efficient and safe.

The comparative study of the fibronectin-binding capacity of S. aureus and S. epidermidis of clinical etiology was carried out. Fibronectin binding was evaluated by original methods: the indirect hemagglutination test and the passive coagglutination test. In this study the occurrence of S. epidermidis isolates, as well as their level (evaluated by the titer) of fibronectin binding, was shown to be lower than those of S. aureus isolates. Fibronectin-binding representatives of S. epidermidis lost this capacity after storage in semiliquid agar at 4 degrees C for 2 months.