[Has the era of warfarin terminated?].

Warfarin has for a long time been considered the "gold standard" of oral anticoagulant therapy. Positive effects of this agent are unambiguously supported by accumulated evidence-based data convincingly confirming a decrease in the risk for thrombolytic complications in patients with many diseases of the cardiovascular system: atrial fibrillation, thrombosis of deep veins of extremities, pulmonary artery thromboembolism. However, warfarin has a series of disadvantages complicating its practical application: the necessity of individual adjustment of the dose to maintain the International Normalized Ratio (INR) within the limits of the target values, clinically significant interactions with other drugs and foodstuffs. In this connection, the advent of new oral anticoagulants such as dabigatran, rivaroxaban, and apixaban is associated with great hopes concerning increased efficiency and safety of anticoagulant therapy. However, while the results of large-scale clinical trials are promising, the data on using these agents in real clinical practice suggest that prescription and administration of new oral anticoagulants should be approached with great caution, thoroughly weighing potential risks and benefits. Therefore, switching over the patients with the already adjusted dosage of warfarin and stable values of the INR to new drugs seems hardly advisable.

[X-ray densitometric characteristics of bone mineral density in patients with impaired biliation].

Dual-energy X-ray absorptiometry was used to examine 20 patients with obstructive jaundice, who had undergone external biliary drainage in the first surgical stage. A clinical comparison group comprised 34 patients without hepatobiliary diseases. Bone mineral density was measured in the lumbar spine, proximal femur, and ultradistal antibrachium. Impaired biliation was found to result in bone loss in the early-stage of the disease, which was more marked in the spongy bone. This allows the ultradistal antibrachium to be identified as a main observation area for dual-energy X-ray absorptiometry to make an early diagnosis of mineralization disorders. The integrated T index (Tint) calculated on the basis of the X-ray densitometry of a few skeletal portions may be used to obtain generalized information on bone mineral density.

[An immunological analysis of bacterial persistence in the bone marrow]. / Immunologicheskii analiz bakterial'noi persistentsii v kostnom mozge.

A method for the evaluation of bacterial persistence in the bone marrow in association with particular clonogenic target cells was developed. The method was based on the negative selection of cells expressing microbial antigens after treatment with hyperimmune antiserum specific to a given infective agent and the subsequent quantitation of target cells thus eliminated in appropriate assays. Using this approach, we demonstrated that Mycoplasma arthritidis and L-forms of Streptococcus strain L-406 were capable of persisting in murine bone marrow in close association with CFUs-7 (a subpopulation of hematopoietic stem cells) for at least several months after experimental infection. Francisella tularensis was also found to be capable to express on the CFUs-7 membranes. Persisting microorganisms enhanced both proliferation and migration of CFUs-7.

Biological activities of lipoteichoic acid and peptidoglycan-teichoic acid of Bacillus subtilis 168 (Marburg).

To evaluate the suitability of Bacillus subtilis as a production host of heterologous proteins for pharmaceutical purposes, we assessed the biological activity of this bacterium and its major cell envelope components, lipoteichoic acid (LTA) and peptidoglycan-teichoic acid complex (PG-TA) in several eukaryotic effector assays. LTA and PG-TA were found to be non-toxic for mice and guinea-pigs in a short-term toxicity assay. PG-TA was weakly pyrogenic and weakly mitogenic. Both LTA and PG-TA acted as immunologic adjuvants in mice and when injected in mice, also caused an increase in the number of granulocyte-monocyte colony-forming cells in the bone marrow probably via stimulation of production of granulocyte-macrophage colony-stimulating factor.

[Antigen-nonspecific suppression of the immune response in mice as affected by pertussis vaccine]. / Antigennespetsificheskaia supressiia immunnogo otveta u myshei pod deistviem kokliushnoi vaktsiny.

A study was made of the suppressorgenic action of killed whole-cell pertussis vaccine prepared from B. pertussis strains 475 and 305. Thymic and splenic lymphocytes of CBA mice 3-7 days following intraperitoneal or intravenous inoculation of pertussis vaccine were shown to inhibit in an antigen-nonspecific manner the plaque-forming cell (PFC) production in the adoptive transfer experiments. Suppression of graft-versus-host reaction was also observed, estimated by the survival of irradiated (CBA X C57BL/6) Fl mice, or by measuring the endogenous colony formation. Suppression-mediating cells were found to be susceptible to complement-dependent lysis by the anti-I-Jk alloantiserum against the specific marker of suppressor T cells, antigen I-J. Furthermore, thymocytes of pertussis vaccine-treated mice were shown to inhibit the endogenous colony formation in syngeneic mice irradiated in sublethal dose. Thus, B. pertussis vaccination of CBA mice resulted in appearance of suppressor T cells that exerted various inhibitory activities in several experimental test-systems.