Formation of low molecular weight oligomers from chitin and chitosan stimulated by plasma-assisted processes.

The controlled degradation of solid powders of chitin and chitosan stimulated by electron-beam plasma (EBP) was experimentally studied. Crab shell chitin and chitosan were used as original substances. The non-equilibrium low temperature EBP was generated by injecting an electron beam into a gaseous medium. Chitooligosaccharides with Mw=800-2000Da and polydispersion 1.5-2.5 were formed due to the EBP-treatment of chitin and chitosan. The ß-1,4 glycosidic bounds in original polymers degrade under the action of active oxygen species produced in the EBP. Low molecular weight products of chitosan inhibited the growth of various yeast-like and filamentous fungi at minimum inhibitory concentration 500mcg/ml. By optimizing the treatment conditions and using special techniques of reaction volume formation the 95% yield of chitooligosaccharides was obtained after 2min whereas the conventional chemical hydrolysis usually takes several days. The EBP-stimulated hydrolysis is promising for effective polysaccharides degradation and can be competitive with traditional technologies.

[The experimental evaluation of antiradiation effectiveness of beta-estradiol on survival rates and bone marrow hemopoiesis of X-ray irradiated mice].

The study was aimed at evaluating the radioprotective effectiveness of beta-estradiol following its prophylactic administration in conditions of acute irradiation. Evaluation of the radioprotective efficiency was performed by studying the 30-day survival rate, life expectancy, the structure of irradiated mice death, the bone marrow hematopoiesis using the method of exogenous colony formation. The prophylactic use of beta-estradiol at doses of 20 and 40 mg/kg 5 days before irradiation has been established to protect the exposed mice against radiation death induced by X-rays at doses LD50-90/30, thus increasing their survival rate by 17-58%, and to favor the reduced expression of post radiation disorders of bone marrow hematopoiesis.

[Effect of indometofen on the survival and bone marrow hemopoiesis of mice exposed to acute external gamma- or X-ray irradiation].

The purpose of the study is evaluation of radioprotective effectiveness of indometofen at its prophylactic administration in conditions of acute irradiation. Evaluation of radioprotective efficiency was performed by studying the 30-day survival rate, life expectancy, structure of deathly irradiated mice, and bone marrow hemopoiesis using methods of endogenous and exogenous colony formation. The prophylactic application of indometofen at doses 30 mg/kg for 5 days before irradiation has been observed to protect mice against radiation death induced by gamma or X-ray exposures at doses LD(50-70/30), increasing their survival rate by 16-44%, and reduce severity of post radiation disorders of bone marrow hemopoiesis.

Treatment during primary HIV infection does not lower viral set point but improves CD4 lymphocytes in an observational cohort.

OBJECTIVE: To investigate if early treatment of primary HIV-1 infection (PHI) reduces viral set point and/or increases CD4 lymphocytes. METHODS: Analysis of two prospective multi-centre PHI cohorts. HIV-1 RNA and CD4 lymphocytes in patients with transient treatment were compared to those in untreated patients. Time to CD4 lymphocyte decrease below 350/ microl after treatment stop or seroconversion was calculated using Kaplan-Meier and Cox-PH-regression analyses. RESULTS: 156 cases of PHI were included, of which 100 had received transient HAART (median treatment time 9.5 months) and 56 remained untreated. Median viral load (563000 cop/ml vs 240000 cop/ml; p<0.001) and median CD4 lymphocyte (449/ microl vs. 613/ microl; p<0.01) differed significantly between treated and untreated patients. Median viral load was 38056 copies/ml in treated patients (12 months after treatment stop) and 52880 copies/ml in untreated patients (12 months after seroconversion; ns). Median CD4 lymphocyte change was +60/ microl vs. -86/ microl (p = 0.01). Median time until CD4 lymphocytes decreased to <350/ microl (including all patients with CD4 lymphocytes <500/ microl during seroconversion) was 20.7 months in treated patients after treatment stop and 8.3 months in untreated patents after seroconversion (p<0.01). Cox-PH analyses adjusting for baseline VL, CD4 lymphocytes, stage of early infection and symptoms confirmed these differences. CONCLUSIONS: Treatment during PHI did not lower viral set point. However, patients treated during seroconversion had an increase in CD4 lymphocytes, whereas untreated patients experienced a decrease in CD4 lymphocytes. Time until reaching CD4 lymphocytes <350/ microl was significantly shorter in untreated than in treated patients including patients with CD4 lymphocytes <500/ microl during seroconversion.

[Mental and behavioral disorders in idiopathic focal epileptiform spikes].

Clinical correlates of so-called "benign epileptiform spikes in children", centro-temporal (rolandic) spikes and occipital spikes, have been studied in 200 children, aged 3-17 years, with mental, behavioral and neuropsychological disorders without epileptic seizures (non-paroxysmal epileptic disorders). Centro-temporal spikes prevailing in the left hemisphere were observed in older children and predominantly related to verbal and speech disorders. Occipital spikes were observed in younger children mainly in the right hemisphere being related to non-verbal and neuropsychological disorders. In both groups, a wide spectrum of behavioral and mental disorders including speech as well as visual and functional disorders, attention deficit and hyperactivity, global mental delay, difficulties in study was observed, the disorders being combined in some cases. Clinical symptoms in both types of spikes are thought to be related to their localization in the brain cortex, functional hemisphere asymmetry and peculiarities of the child neurodevelopment. The pathological types presented in the study should be named "idiopathic focal epileptiform spikes in children". In all cases, both children with respective forms of epilepsy and those with epileptiform phenomena being not combined with epileptic seizures should undergo encephalographic, neuropsychological and pediatric examination. Should the respective disturbances be found, children would need a treatment directed to the EEG-controlled inhibition of epileptiform activity. The data obtained suggest that this treatment improves children school adaptation and school results. The drugs of choice are valproic acid (depakine chrono), lamotrigine (lamictal), levetiracetam (keppra).

[A mission to Mars: the prognostic analysis of concurrent psychological problems]. / Polet na Mars: prognosticheskii analiz soputstvuiushchikh psikhologicheskikh problem.

Psychological implications of situations that may take place during a mission to Mars including desynchronosis, fatigue, psychic asthenization, acute mental disorders, interruption of the information flow, unpredicted transformation of the socio-psychological needs, a persistent conflict tension in the crew, errors in manual control of the vehicle, refusal or impossibility to fulfill an operation, difficulties in communication between the crew and ground controllers were analyzed for determination of their causes and consequences, probable starting time, ways and methods of preventing and surmounting each of these situations.

[Psychological aspects of training for and implementation of a piloted expedition to Mars]. / Psikhologicheskie aspekty podgotovki i osushchestvleniia pilotiruemoi ékspeditsii na Mars.

Reviewed are the modern notions of the main psychological concerns regarding a mission to Mars which are maintenance of mental health, high professional reliability, and successful readaptation of the Martian crew on return to Earth. The unprecedent trail-blazing interplanetary mission distinguished by autonomy, long period, international crew and a broad range of tasks to tend will set particularly difficult requirements to the psychological support system. Among them prioritized are purposeful character building and training of future crew members already in childhood and youth. The primary goal is to bring up personality with anthropocosmic thinking as a professional quality that will eventually determine personal and professional reliability. Within the system of psychological support, the central place should be given to monitoring of crew mental heath and behavior, and preventive an corrective measures. The longer Martian day (24 hr. 36 min.) rises the issue of effective adaptation to this factor. Special simulators will be required aboard the vehicle to help the crew refresh skills in manipulation of the dynamic board systems. The program of psychological support to the Martian crew must be thoroughly tested in model studies (Antarctic field, ground-based experiments, orbital flights, Lunar base).

[Intergral criterion and prediction of cosmonauts professional reliability in flight]. / Integral'naia otsenka i prognoz professional'noi nadezhnosti kosmonavtov v polete.

Discussed is the problem of professional reliability of cosmonauts simulating manual docking of transport vehicle SOYUZ-TM to space station MIR during acute adaptation to microgravity. A new concept of cosmonaut's reliability qualification is based on the parameters that characterize the systemic body response to job-related factors: integral efficiency and psychophysiological "cost". Justification is given to the statistic methodology of the change-over from prime job quality indices and the functional state of human to integral. Underlined is the possibility to apply this methodical approach to enhancement of the program of assessment and recovery of the professional reliability of cosmonauts in flight.

[The use of low-frequency ultrasound in the combined therapy of pulmonary tuberculosis patients]. / Primenenie nizkochastotnogo ul'trazvuka v kompleksnoi terapii bol'nykh tuberkulezom legkikh.

The validity of low-frequency ultrasound (LFU) addition to specific therapy of pulmonary tuberculosis (PT) was investigated in 2 groups of PT new cases. The study group (n = 25) received specific therapy and ultrasonic treatment (44 KHz, amplitude 2 microm to the paravertebral region and PT zones). The control group (n = 25) received specific therapy only. The response to treatment was higher in the study group. The findings support validity of low-frequency ultrasound use as an adjuvant in treatment of PT new cases.

[The aspects of psychophysiological analysis of erroneous actions performed by astronauts]. / Nekotorye aspekty psikhofiziologicheskogo analiza oshibochnykh deistvii kosmonavtov.

The experience of manned space missions points to the fact that cosmonaut-operator plays an important role in providing the efficiency and reliability of the crew-spacecraft system. However, the spaceflight factors can have a negative effect on working capacity of crewmembers and give rise to their operational errors. The paper deals with the methodical approach to analysis of the interrelationship of errors and psychophysiological state of cosmonauts as well as the ways of its realization. Described are the system of indices used for expert assessment of the psychophysiological state, peculiarities of work-rest schedule, and intra- and intergroup interaction. Potentialities of this approach are evidenced by results of the analysis of data from one of the MIR missions.

[The organizational problems in the postgraduate and additional professional training of military physicians]. / Nekotorye organizatsionnye voprosy poslevuzovskogo i doponitel'nogo professional'nogo obrazovaniia voennykh vrachei.

In the article materials of social research on problems of postgraduate and additional vocational training are analyzed. Original analytical results are received, which characterize real periodicity and volume of increase of qualification of the military doctors, permit deeper to estimate necessity of perfection of military-medical education, put particular questions, concerning improvements of quality of professional training. Research lead to the conclusion about necessity of further scientific search in this direction.

[Intensification of genomic dactyloscopy by means of hybridization with modified oligonucleotides, forming duplexes with increased stability]. / Intensifikatsiia genomnoi daktiloskopii putem gibridizatsii s modifitsirovannymi oligonukleotidami, obrazuiushchimi dupleksy s povyshennoi stabil'nostiu.

The modified oligodeoxyribonucleotide (m5C-n2A-m5C)5 containing 5-methylcytosine and 2-aminoadenine instead of cytosine and adenine residues, respectively has been used as a hybridisation probe in DNA fingerprinting. The oligonucleotide, due to the substitutions forms more stable duplexes with complementary sequence in DNA than the corresponding nonmodified pentadecanucleotide. The comparison with its natural counterpart displays considerably increased intensity of bands in patterns obtained with modified analog. The use of such analogues can increase sensitivity and shorten time of DNA fingerprinting.