[A new mode of brachial plexus block].

This paper describes a new method of brachial plexus block via subclavian access. The method minimizes the risk of pneumothorax, impairments of nerves and vessels and does not require the use of an electrical stimulator. In addition, it prevents catheter migration during continuous analgesia.

[Effect of the bone cement on human fibroblast culture and possible ways of its correction by cytoprotector preparations]. / Osobennosti deistviia kostnogo tsementa na fibroblasty cheloveka v kul'ture i vozmozhnye puti ego korrektsii s pomoshch'iu tsitoprotektornykh preparatov.

The results of in vitro investigation are used to assess the effect of poly(methyl methacrylate) based bone cements (BCs) upon human fibroblast culture. The dose dependent cytotoxic effect of BCs (Polacris) was manifested by the development of oxidative stress and hypoxia (on the cell level) and by a decrease in the cell ability to multiplication. The drugs possessing antihypoxant (mafusol) and antioxidant (erysod) activity, introduced into the incubation medium in clinically adequate doses, significantly reduced the toxic effect of BCs. The maximum positive effect was observed upon a combined administration of both drugs.

[Mechanisms of the optimization of oxygen metabolism under the effects of mafusol and mildronate during emergency implantation of hip prosthesis]. / Mekhanizmy optimizatsii kislorodnogo biudzheta organizma pod vliianiem mafusola i mildronata pri ékstrennom éndoprotezirovanii tazobedrennogo sustava.

The results of using antihypoxants Mafusol and Mildronate in the course of emergency endoprosthesis of the hip joint were analyzed in 41 patients at the age of (80.5 +/- 5.6) years with fractures of the proximal part of the femoral bone. The authors noted optimization of the organism oxygen budget under the influence of the drugs, its physiological mechanisms being deciphered. The protective properties of these drugs manifested themselves in lower consumption of oxygen by the tissues with greater possibilities of its release by oxyhemoglobin as well as in the lessening of intrapulmonary shunting and prevention of the development of metabolic acidosis.

[The study of the Ca2+ role in cytotoxic response of human cells in culture to the action of xenobiotics]. / Issledovanie uchastiia ionov kal'tsiia v toksicheskom deistvii ksenobiotikov na kletki cheloveka v kul'ture.

The role of Ca2+ in mechanisms of cell death, necrosis and apoptosis is diverse and generally recognized. The purpose of this work was to study Ca2+ participation in a cytotoxic response of human cultured cells in the presence of toxic concentrations of cationic antiseptic substance poly(hexamethylene guanidine), anionic surfactant SDS and monomeric methyl methacrylate (a component of bone cement applied in surgery). Human cell line U-937 grown in suspension was used for this study. A fluorescent probe chlortetracycline was used, as an indicator of Ca2+ transport through biologic membranes. Our results show that weakly toxic concentrations of xenobiotics under study, close to the minimum toxic doses, nearly always provoke a fair but statistically significant drop in Ca2+ binding by cells. At the same time, higher toxic doses lead to significant increase in Ca2+ influx. The latter event well compares with the majority of literary data, while the mentioned decrease in Ca2+ influx at low toxic concentrations of xenobiotics presumably correlates with the initial stage of acute cytotoxic response, accompanied by a metabolic activation and enhanced resistance of cells to injuring stimuli, demonstrated by the authors elsewhere. In parallel, a possible effect of Ca(2+)-channel antagonist nifedipine was explored under conditions of cytotoxic response of cell lines U-937, A-549 and human embryonic lung fibroblasts to poly(hexamethylene guanidine). Nifedipine (10 microM) was introduced in the incubation medium simultaneously with the toxic agent, and the cells were further maintained for 5 or 24 h in culture; their viability was monitored with the microtetrasolium test or by assessment of LDH leakage into the incubation medium. The effect of nifedipine proved to be dual, depending on the applied concentration of toxic agent: at low toxic concentrations the improvement of viability could be noticed, while at more pronounced toxic doses aggravation of viability was evident. From our point of view the explanation of this result could be the following. In weakly toxic conditions, as in intact cells, Ca2+ influx is brought about by specific mechanisms, mainly through Ca(2+)-channels, that is why nifedipine partly abolishes Ca(2+)-dependent cytotoxic response. At high concentrations, cell plasma membrane is directly damaged by toxic agent, Ca2+ enters cells mainly non-specifically, so that Ca2+ antagonist cannot protect cell injury. The reason of toxic effect aggravation by nifedipine in these conditions is still waiting for its explanation.

[Cytoprotective effect of antihypoxic and antioxidant preparations on cultured human cells in a model of toxic response]. / Tsitoprotektornoe deistvie antigipoksicheskikh i antioksidantnykh preparatov na kletki cheloveka v kyl'ture pri modelirovanii toksicheskogo otveta.

An oxidative stress is considered to be one of the major mechanisms of cytotoxicity. The purpose of present work was to study effects of some drugs with antihypoxic/antioxidant activity in cultured human lung embryonic fibroblasts under conditions of cytotoxic response, provoked by cationic or anionic antiseptics. The following preparations were under study: Mafusol (Na-fumarate), superoxide dismutase from human erythrocytes (SOD), cytochrome c, alpha-tocopherol and Thioctacid T (lipoate) which were applied at concentrations comparable with those, employed in clinical application. The combinations of the used drugs were also under study. The cytotoxic response was induced by an application of antiseptics into the cell incubation medium in 2-5 fold dilutions up to minimum toxic doses for 2-24 h. The drugs under study were introduced simultaneously with antiseptics. The maximum cytoprotective effect was revealed in the case of combination fumarate-alpha-tocopherol; the combination fumarate plus SOD being the second in effectiveness. When the drugs were introduced separately, the most effective proved to be fumarate, followed by vitamin E and cytochrome c. SOD and lipoate did not reveal any cytoprotective activity in our experimental conditions. The designed model of cytotoxicity in vitro can be considered as a prospective test-system for the screening of cytoprotective drugs and their combinations.

[The enhanced relative intensity of cAMP-dependent protein phosphorylation in stomach tumors]. / Uvelichenie otnositel'noi intensivnosti cAMP-nezavisimogo fosforilirovaniia belkov v opukholiakh zheludka.

The activity of cAMP-dependent histone kinases (HK) and cAMP-independent casein kinases (CK) as well as cAMP level were assessed in gastric mucosa affected by various forms of gastritis as well as in gastric tumor and adjacent normal tissue. CK activity was higher whereas that of HK and cAMP level were lower in tumor and at a distance of 5-20 cm from its edge as compared to gastritis. CK/HK cAMP ratio in adenocarcinoma was 6 times that in normal tissue and 2-2.5 times that in gastritis. The data obtained and those published earlier suggest the relative increase in cAMP-independent protein phosphorylation with respect to its cAMP-dependent counterpart to be characteristic of human tumors.

[Protein kinase activity and cAMP level in gastric mucosa in non-neoplastic diseases]. / Aktivnost' proteinkinaz i soderzhanie cAMP v slizistoi obolochke zheludka pri neopukholevykh zabolevaniiakh.

Activity of cAMP-dependent and -independent protein kinases as well as content of cAMP were studied in biopsy preparations of gastric mucosal membranes obtained from patients with superficial gastritis, erosion, ulcer, adenomatous polyps and ulcer after treatment with laser irradiation. All the patterns studied were similar in preparations of adenomatous polyps and normal mucosal membrane. Activity of cAMP-independent protein kinases was increased under conditions of erosion, ulcer, gastroduodenal reflux and, especially, in ulcer tissue treated with laser. However, the ratio between cAMP-independent and -dependent phosphorylation was increased only in 50% of ulcerous diseases and in gastroduodenal reflux. The equilibrium of cAMP-dependent and -independent phosphorylation was not altered in the other impairments studied even though benign proliferation was stimulated using laser irradiation.