Immunocorrecting properties of low-frequency ultrasound

The possibility to correct the secondary immunodeficient state by means of two- and three-fold low frequency ultrasound effect on the spleen has been demonstrated on mice of CBA strain. It makes it possible to use low-frequency ultrasound on a large scale in the clinical practice.     

Nerve-blocking properties of antibiotics]

Comparative data on the neuroblocking activity of antibiotics of various groups in acute experiments on albino mice and narcotized cats are presented. It was found that according to the impairments in the neuro-muscle conductivity the drugs were arranged in the following descending order: polymyxin B, neomycin, gentamicin, streptomycin, lincomycin and kanamycin. The streptomycin derivatives were approximately 2 times less toxic than streptomycin. The problems of the mode of action of the antibiotics on conductivity of excitation in the neuro-muscle synapses are discussed.     

The effect of fenazepam on the humoral immune response in secondary immunodeficiency]

A single administration of phenazepam (2.5 mg/kg) enhances the synthesis of antibodies after immunization with different vaccines. Phenazepam restores antibody formation in immunodeficiency induced by intoxication. The immunostimulating effect of phenazepam is linked with an increase in the capacity of macrophages for inducing humoral immune response and a rise in the number of antibody-producing cells in the spleen.     

Effect of penicillin series antibiotics on the properties of Brucella]

Investigation of the properties of antibiotic-resistant variants obtained experimentally from various species of Brucella indicated that benzylpenicillin, ampicillin and ceporin induced significant changes in the main properties of Brucella, i.e. phagolysability, agglutinability, production of brucellacin and hydrogen sulfate, attitude to dyes. Only the nutrient requirements of Brucella did not change when it was grown on synthetic media which is of great importance for investigation of changed Brucella strains.     

Intravenous immunoglobulin for secondary immunodeficiency

Viral and bacterial infections are a serious cause of morbidity and mortality in patients immunocompromised as a result of malignancy, burns, trauma, viral infections or chemotherapy. The development of safe and effective antibody preparations suitable for intravenous use have transformed the lives of patients suffering from forms of primary immunodeficiency characterised by antibody deficiency. However, the role of intravenous immunoglobulin (IV IgG) preparations in the treatment of secondary immunodeficiencies is less clear and although many anecdotal reports exist for the use of IV IgG in various secondary immunodeficiencies (Table 1), there have been few controlled trials of a sufficient size that have demonstrated clear-cut efficacy in many of the suggested new indications.     

Surface-active properties of antibiotics

The critical concentrations of the mycella formation of novobiocin, mithramycin, variamycin, erythromycin, oleandomycin and lincomycin were determined with two methods by changes in the isotherms of the surface tension and in the maximum absorption of rodamine due to the antibiotic concentrations. The results obtained with the two methods were comparable.     

Effect of gamma-irradiation on some biological and physico-chemical properties of polyene antibiotics]

Deep effect of gamma-rays on polyenic antibiotics was studied. It was shown that gamma-radiation induced radiation-chemical oxidation of the substances. The chromatographic analysis showed that the levorin degradation products were identical to the polyenic products of the antibiotic oxidative destruction. As for mycoheptin and amphotericin B, destruction of their molecules to non-polyenic products was observed. It was found that toxicity of the levorin aromatic heptaen did not practically change after gamma-irradiation in high doses. The toxicity of mycoheptin and amphotericin B, non-aromatic heptaens increased after exposure to high doses of gamma-rays.     

Synthesis and antineoplastic properties of anthracycline antibiotics modified by a sugar residue]

The present review (for the previous part, see Bioorganicheskaya Khimia. 1990. V. 16. No 11. P. 1445-1464) describes the most important studies in the chemical modifications of the sugar moiety of anthracycline antibiotics and their analogues during last ten years.     

Effect of tetracycline group antibiotics on the barrier properties of the small intestine epithelium]

The effect of 5 tetracyclines on the barrier and transport properties of the small intestine epithelium was studied. The barrier properties were estimated by a change in the ionic selectivity and conductivity of the epithelium, as well as by enterocyte linkage. The current of the short circuit served the characteristics of the Na transport system state. Dimethylchlortetracycline, methacycline and oxytetracycline in concentrations of 10(-7) g/ml decreased the epithelium conductivity and increased the cell linkage. Tetracycline and methacycline in concentrations of 10(-9) g/ml had an analogous effect. The effect was observed 10--20 minutes after the start of incubation with the substance. No effect on the current of the short circuit was observed within the concentrations of 10(-4) to 10(-9) g/ml. It is suggested that the decreased conductivity and increased linkage are due to adsorption of the tetracycline molecules in the region of close cell contacts.     

Sensitivity of Shigella to antibiotics]

Three hundred and twenty two Shigella cultures isolated from dysentery patients within 1986-1989 were tested with the use of standard paper disks for their sensitivity to levomycetin, streptomycin, tetracycline, monomycin, neomycin, kanamycin, erythromycin, gentamicin, carbenicillin, ampicillin, oxacillin, methicillin and doxycycline. The number of the cultures belonging to Shigella sonnei amounted to 85.1 per cent of the total number of the strains studied. 91.9, 89.5, 87.3, 87.3, 80.1 and 80.1 per cent of the cultures were sensitive to gentamicin, kanamycin, carbenicillin, neomycin, levomycetin and ampicillin, respectively. 99.4 per cent of the isolates were resistant to streptomycin and 97.2 per cent were resistant to tetracycline. The sensitivity to erythromycin remained rather high (70.2 per cent). The overwhelming majority of the Shigella sonnei isolates had multiple resistance.     

Evaluation of lymphocyte differentiation in primary and secondary immunodeficiency diseases

The differentiation status of T and B cells was evaluated in patients with common variable immunodeficiency (CVI), selective IgA deficiency (IgA), X-linked agammaglobulinemia (XLA), and the acquired immune deficiency syndrome (AIDS) with the use of conventional lymphocyte markers and four new monoclonal antibodies that identify lymphocyte subpopulations. These antibodies are HB 4, which identifies a subpopulation of resting B cells; HB 5, which identifies the C3d/EBV receptor on mature B cells; HB 7, which identifies immature B lymphocytes; and HB 10, which reacts with virgin but not activated or memory T cells. T and B cells from the IgA patients typically had normal phenotypic profiles, whereas diverse patterns of lymphocyte maturation were observed in CVI. In 11 of 16 CVI patients, B cells had normal antigenic phenotypes. Although B cells from four other CVI patients had normal frequencies of HB 5 and HB 7 antigen expression, few expressed the HB 4 antigen, suggesting that they were activated. In contrast, a large percentage of B cells from one CVI patient were of an immature phenotype. The expression of the HB 10 antigen by T cells in CVI patients was also variable, being normal in 10 of 16 patients, yet significantly decreased in six others. The vast majority of the limited numbers of IgM B cells from five XLA patients (greater than 100-fold reduction) has an immature phenotype (HB 4-5-7+). Interestingly, the circulating T cells in XLA patients were phenotypically similar to those in normal newborns, suggesting that T cell immaturity or defective T cell activation may occur in these B cell-deficient individuals. Circulating B cells from AIDS patients were mostly HB 7-, with variable expression of the HB 4 antigen and significantly decreased expression of the HB 5 antigen. Most of the T cells from AIDS patients were HB 10-, and thus appeared to be activated.     

Side effects of antibiotics in rheumatic diseases]

Complications due to antibiotic therapy in rheumatic patients subjected to season bicillin prophylaxis in Minsk within 1965--1975 and in patients with extensive collagenoses were studied. Allergic complications mainly ih the form of allergic reactions in the patients treated with bicillin-3 or picillin-5 were observed in 7.8--16.8 per cent of the patients. Within 10 years 52 cases of anaphylactic shock due to the bicillin use were recorded. Side reactions to antibiotics were observed in 16 (17.3 per cent) out of 92 patients with extensive collagenoses. For prophylaxis of the above complications it is recommended to use rational antibiotic therapy in rheumatic patients, strict registration of allergological states in the anamnesis, testing of microbial sensitivity to the antibiotics.