A Model of Acute Peritonitis.

The biological models used in the study of generalized peritonitis can be subdivided into 5 groups (introduction of foreign bodies, cultures of microorganisms, suspensions of feces, chemicals, and mechanical damage to the gastrointestinal tract) or into 4 groups (introduction of foreign bodies, chemicals, bacterial contamination of the abdominal cavity, and combined methods). After analysis of published reports, the most justified classification of methods of peritonitis modelling is based on the type of peritonitis-inducing agent and the administration route and on the nature of peritonitis developing in the abdominal cavity. The choice of the model maximally close reproducing clinical conditions of peritonitis should be based on the specific objectives of the study, focusing on the etiology, pathogenesis, and severity of the disease course, planned measures aimed at eliminating the process, and other factors.

Simulation of Mechanical and Thermal Wounds of Soft Tissues.

Millions of accidental and surgical injuries of soft tissues are registered annually around the world [5]. Untimely and insufficiently effective treatment of wounds in 50-70% leads to the development of purulent-septic infection and the development of septic conditions and fatal outcomes [1-4], which necessitates thorough study of inflammatory and regenerative processes occurring in the injured soft tissues. Various models of mechanical and thermal damage to soft tissues are proposed for studying the inflammatory and reparative processes, for assessing the therapeutic effects and developing new approaches to wound treatment. However, the developed models do not fully meet the requirements of researchers and are not always simple and uniformly reproducible, close to the course of the pathology in humans, and highly reliable. When choosing the model of mechanical and thermal wounds, the experience of other researchers should be taken into consideration due to the need of actualization and improvement of existing models.

[Dynamics of mortality according to the materials of the forensic medical examination bureau of a particular region]. / Dinamika smertnosti po materialam byuro sudebno-meditsinskoi ekspertizy otdel'no vzyatogo regiona.

OBJECTIVE: To show the dynamics of the structure of deaths of the main types of violent and non-violent death on the material of the thanatological department of a separate regional bureau of forensic medical examination. Among the violent causes are considered: mechanical injury, mechanical asphyxia, transport injury, poisoning. Among the nonviolent causes of death the diseases of circulatory system, pneumonia, infectious and oncological pathology have been studied. The period from 2001 to 2020 was investigated. Dynamic changes over a selected period are most clearly demonstrated by the ratio of numerical data to the original 2001 indicators taken as 100%. The data presented objectively reflecting the dynamics of the number and proportion of certain types of death are only the initial stage of the analysis undertaken. The second step should be the determination of the causes of the identified changes that require an integrated approach including medical, demographic and socio-economic data.

Amplification of Relativistic Electron Bunches by Acceleration in Laser Fields.

Direct acceleration of electrons in a coherent, intense light field is revealed by a remarkable increase of the electron number in the MeV energy range. Laser irradiation of thin polymer foils with a peak intensity of ∼1×10^{20} W/cm^{2} releases electron bunches along the laser propagation direction that are postaccelerated in the partly transmitted laser field. They are decoupled from the laser field at high kinetic energies, when a second foil target at an appropriate distance prevents their subsequent deceleration in the declining laser field. The scheme is established with laser pulses of high temporal contrast (10^{10} peak to background ratio) and two ultrathin polymer foils at a distance of 500 µm. 2D particle in cell simulations and an analytical model confirm a significant change of the electron spectral distribution due to the double foil setup, which leads to an amplification of about 3 times of the electron number around a peak at 1 MeV electron energy. The result verifies a theoretical concept of direct electron bunch acceleration in a laser field that is scalable to extreme acceleration potential gradients. This method can be used to enhance the density and energy spread of electron bunches injected into postaccelerator stages of laser driven radiation sources.

Coulomb-driven energy boost of heavy ions for laser-plasma acceleration.

An unprecedented increase of kinetic energy of laser accelerated heavy ions is demonstrated. Ultrathin gold foils have been irradiated by an ultrashort laser pulse at a peak intensity of 8×10^{19} W/ cm^{2}. Highly charged gold ions with kinetic energies up to >200 MeV and a bandwidth limited energy distribution have been reached by using 1.3 J laser energy on target. 1D and 2D particle in cell simulations show how a spatial dependence on the ion's ionization leads to an enhancement of the accelerating electrical field. Our theoretical model considers a spatial distribution of the ionization inside the thin target, leading to a field enhancement for the heavy ions by Coulomb explosion. It is capable of explaining the energy boost of highly charged ions, enabling a higher efficiency for the laser-driven heavy ion acceleration.

MeV negative ion source from ultra-intense laser-matter interaction.

Experimental demonstration of negative ion acceleration to MeV energies from sub-micron size droplets of water spray irradiated by ultra-intense laser pulses is presented. Thanks to the specific target configuration and laser parameters, more than 10(9) negative ions per steradian solid angle in 5% energy bandwidth are accelerated in a stable and reliable manner. To our knowledge, by virtue of the ultra-short duration of the emission, this is by far the brightest negative ion source reported. The data also indicate the existence of beams of neutrals with at least similar numbers and energies.

[Free amino acids and reducing sugars in the freshwater shrimp Gammarus lacustris (Crustacea, Amphipoda) at the initial stage of preparation to winter season].

A peculiarity of amino acid profile of the cold-resistant freshwater shrimp Gammarus lacustris in the beginning of autumn is a high level of ornithine, the second after alanine (17.0 +/- 1.4 and 22.6 +/- 1.4 micromol/ml of homogenate, respectively). The amount of alanine and ornithine accounts for 39.8% of the total pool of free amino acids and together with lysine and leucine - 55%. Free glucose is the major reducing sugar (6.42 +/- 0.78 micromol/ml).

Directional laser-driven ion acceleration from microspheres.

Laser-driven ion acceleration is capable of generating ion beams of MeV energy exhibiting unique attributes such as ultralow emittance. Research is still focusing on fundamental laser-target interactions to control further beam attributes. In this Letter we present the observation of directional ion acceleration of irradiated spherical targets through proton imaging. This feature, together with an earlier observed quasimonoenergetic proton burst makes spherical targets extremely attractive candidates for high quality, high repetition rate sources of laser accelerated particles.

[Congelation of cryoprotective solutions and cryopreservation of fish sperm].

The influence of additional components and the velocity of cooling on the freezing of cryoprotective solutions has been studied using the cryomicroscopy technique. It was shown that additional components and the rate of cooling of cryoprotective medium fundamentally change the ice area of microparticles and the survival of fish spermatozoa during the freezing-thawing procedure.

Cl- conduction of GABA(A)-receptor complex of synaptic membranes of rat brain cortex after development of chronic epileptization of the brain (pharmacological kindling).

Experiments on Wistar rats showed that basal and muscimol-induced 36Cl- entry into synaptoneurosomes isolated from the brain cortex decreased after kindling (30 mg/kg pentylenetetrazole intraperitoneally for 30 days) in animals with seizure severity score 4-5. Changes in Cl- conduction during kindling are discussed.

[Intraoperative ultrasound diagnosis in the removal of intraocular foreign bodies].

The paper provides a rationale and indications for diascleral removal of foreign bodies from the anterior chamber of the eyeball, by intraoperatively using ultrasound study. The clinical material presents 148 cases of diascleral removal of foreign (49 magnetic and 49 amagnetic) bodes impacted into the tunics of the anterior eye without evident opacities of optical media and without signs of endophthalmitis. The paper provides a pathogenetic rationale for the method that is lowly traumatic and highly effective (foreign bodies being removed in 99.9% of cases) due to the high precision of location of a scleral cut in the projection of foreign body bedding owing to intraoperative sound usage. A model clinical case of fragment removal is also shown in the paper. The specific features of criteria for using the method are described, by taking into account the anatomic characteristics of orbital eyeball location.

Effect of classic convulsants on Cl- conductance of the GABA(A) receptor complex in membranes of cerebral cortex cells at the early stage of kindling.

Muscimol-stimulated Cl- conductance of synaptoneurosomes from the cerebral cortex of Wistar rats increased during the early stage of pharmacological kindling not inducing the seizure response in animals. Picrotoxin, bicuculline, and pentylenetetrazole potentiated inhibition of muscimol-dependent 36Cl- entry into synaptoneurosomes, which attested to increased sensitivity of the GABA(A) receptor/Cl- ionophore complex to classic convulsants.

Cl(-) conduction of GABAA receptor complex of synaptic membranes in the cortex of rats at the middle stage of chronic cerebral epileptization (pharmacological kindling).

Experiments on Wistar rats showed a decrease in basal and muscimol-stimulated 36Cl(-) entry into synaptoneurosomes isolated from the cerebral cortex during the middle stage of kindling (30 mg/kg pentylenetetrazole intraperitoneally for 14 days) characterized by the development of convulsions of higher (2 points) severity in comparison with the previous stage.

Energetic proton acceleration and bunch generation by ultraintense laser pulses on the surface of thin plasma targets.

Energetic proton acceleration from concave targets, the front of which were irradiated with 40 fs laser pulses with an intensity of 10(20)W/cm(2), has been studied as a function of the depth of the concave shape. Three kinds of targets, a triangular concave target, a circular concave target and a parabolic concave target are considered. When the depth of the concave shape was varied, the peak proton energy showed a maximum. The underlying mechanism for the existence of a maximum peak proton energy is presented by tracing the proton trajectory. It is concluded that a parabolic concave target is the best, among the targets considered, for accelerating a proton beam, since a proton beam from a parabolic concave target goes through the strongest electric field.

Cl- conduction of GABA(A) receptor complex on synaptic membranes in rat cortex at the early stage of chronic cerebral epileptization.

Experiments on Wistar rats showed that muscimol-stimulated Cl(-) conduction of synaptoneurosomes, isolated from the cerebral cortex increased after 5-day systemic treatment with subconvulsive doses of pentylene tetrasole during the initial stage of pharmacological pentylene tetrasole kindling, characterized by gradually augmenting convulsive readiness of the brain. This indicates an increase in functional activity of the GABA(A) receptor/Cl(-) ionophore complex.

Electron bunch trapping and compression by an intense focused pulse laser.

A focused short-pulse laser of TEM (1,0)+TEM (0,1) mode has two intensity peaks in the radial direction, so that the transverse ponderomotive force may trap electrons between the two peaks. At the same time the longitudinal ponderomotive force may accelerate electrons at the head of the laser pulse, when the laser is focused. When the electrons move to the laser tail, the laser may diverge and the electron deceleration becomes relatively weak. Our numerical analyses demonstrate that electrons are trapped well by the laser potential well, and that at the same time the acceleration by the longitudinal ponderomotive force induces the electron bunch compression. This trapping and compression mechanism is unique: the electron bunch can be compressed to the scale of the laser pulse length.

[The method of parietal-cavitary sanitation of intestines in complex treatment of acute diffuse peritonitis]. / Metod pristenochno-polostnoi sanatsii kishechnika v kompleksnom lechenii ostrogo rasprostranennogo peritonita.

Experimental investigations carried out in 154 white rats and 24 mongrel dogs have proved pathogenetical effectiveness and safety of using the method of parietal-cavitary sanitation of the intestine in treatment of acute experimental peritonitis. This method used in complex treatment in 28 patients with acute diffuse peritonitis allowed a 1.5-2 times quicker arrest of the syndrome of endogenous intoxication and liquidation of intestinal paresis. Infectious complications were 43% less frequent and the lethality indices were reduced by 9.5% as compared with the results obtained in the control group.

Effect of single injection of pentylenetetrazole in a subconvulsive dose on Cl- conductance of the GABAA-receptor complex.

Muscimol-stimulated Cl(-)conductance in brain cortex synaptoneurosomes from Wistar rats decreased 15 min after single intraperitoneal injection of pentylenetetrazole in a subconvulsive dose. These changes reflected a decrease in functional activity of the GABA(A)-receptor/Cl(-)ionophore complex. Muscimol-stimulated Cl(-)conductance in synaptoneurosomes returned to normal 48 h after pentylenetetrazole administration.

[The condition of the antioxidant system and lipid peroxidation in victims with a severe compound trauma]. / Sostoianie protsessov perekisnogo okisleniia lipidov i antioksidantnoi sistemy u postradavshikh s tiazheloi sochetannoi travmoi.

The study was made of lipid peroxidation (LPO) and antioxidant system (AOS) in 50 victims with a severe compound trauma regarding the patients' condition assessed by APACHE II scale at admission to a critical care unit. It is shown that disorders in the system LPO-AOS depend on severity of the trauma and manifest most obviously in most severe trauma, therefore the degree of LPO-AOS imbalance is a significantly informative criterion of pathobiochemical disturbances. The coefficient K, the indicator of imbalance in the system LPO-AOS, is proposed as a pathogenetically sound criterion of the assessment of the patient's condition severity in the victims with a severe compound trauma.