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The study on the mutagenic activity of commercial synthetic cationic, anionic, amphoteric and nonionogenic surface active substances with antimicrobial properties demonstrated that they had no mutagenic effect on the microbial test systems, i.e. the histidine-deficient strains of Salmonella typhimurium on direct contact and under conditions of metabolic activation in vitro and in vivo. The cationoactive preparation B Kh-14 with the benzyl radical adjoining the nitrogen atom and linear hydrophobic C13H27 with the amide group having a pronounced antimicrobial effect on gram-positive and gram-negative bacteria and fungi showed no carcinogenic activity in the experiments with its long-term action on the urinary bladder mucosa and skin of rats, guinea-pigs and dogs.  相似文献   
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Background  

The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics.  相似文献   
4.
Various catalytic antibodies or abzymes have been detected recently in the sera of patients with several autoimmune pathologies, where their presence is most probably associated with autoimmunization. Recently we have shown that DNase, RNase, and polysaccharide-hydrolyzing activities are associated with IgGs from the sera of patients with multiple sclerosis (MS). Here we present evidence demonstrating that highly purified MS IgGs (but not Igs from the sera of healthy individuals) catalyze specifically hydrolysis of human myelin basic protein (hMBP). In contrast to many known proteases, IgGs do not hydrolyze many other different proteins. Specific inhibitors of acidic and thiol proteases have no remarkable effect on proteolytic activity of IgGs. However, specific inhibitor of serine (PMSF, AEBSF, and benzamidin) and metal-dependent (EDTA) proteases significantly inhibit activity of proteolytic abzymes. Interestingly, the ratio of serine-like and metal-dependent activities of MS IgGs varied very much from patient to patient. The findings speak in favor of the generation by the immune systems of individual MS patients of a variety of polyclonal anti-MBP IgGs with different catalytic properties.  相似文献   
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The effect on microorganisms of electromagnetic and magnetic fields (EMF, MF), the frequency and intensity of which were similar to natural ones, was studied. They were found to influence the physiology of bacteria. Changes in the rate of proliferation of microbes, in their susceptibility to antibiotic the frequency of formation of recombinants and partial diploids during conjugation of colibacterium were observed during cultivation in these fields.  相似文献   
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Background

The Mongolian gerbils are a good model to mimic the Helicobacter pylori -associated pathogenesis of the human stomach. In the current study the gerbil-adapted strain B8 was completely sequenced, annotated and compared to previous genomes, including the 73 supercontigs of the parental strain B128.

Results

The complete genome of H. pylori B8 was manually curated gene by gene, to assign as much function as possible. It consists of a circular chromosome of 1,673,997 bp and of a small plasmid of 6,032 bp carrying nine putative genes. The chromosome contains 1,711 coding sequences, 293 of which are strain-specific, coding mainly for hypothetical proteins, and a large plasticity zone containing a putative type-IV-secretion system and coding sequences with unknown function. The cag -pathogenicity island is rearranged such that the cag A-gene is located 13,730 bp downstream of the inverted gene cluster cag B- cag 1. Directly adjacent to the cag A-gene, there are four hypothetical genes and one variable gene with a different codon usage compared to the rest of the H. pylori B8-genome. This indicates that these coding sequences might be acquired via horizontal gene transfer. The genome comparison of strain B8 to its parental strain B128 delivers 425 unique B8-proteins. Due to the fact that strain B128 was not fully sequenced and only automatically annotated, only 12 of these proteins are definitive singletons that might have been acquired during the gerbil-adaptation process of strain B128.

Conclusion

Our sequence data and its analysis provide new insight into the high genetic diversity of H. pylori -strains. We have shown that the gerbil-adapted strain B8 has the potential to build, possibly by a high rate of mutation and recombination, a dynamic pool of genetic variants (e.g. fragmented genes and repetitive regions) required for the adaptation-processes. We hypothesize that these variants are essential for the colonization and persistence of strain B8 in the gerbil stomach during inflammation.  相似文献   
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Using a novel approach, we have analyzed 30 parameters characterizing detailed spectrum and fractional content of LPs in plasma of patients with tick-borne encephalitis (TBE). The blood plasma of all TBE patients (30 patients), as compared with that of healthy individuals (120 patients), is characterized by decreased concentrations of many LP subfractions and of the total concentration of all plasma LPs (hypolipoproteinemia). The observed difference in some parameters was statistically significant. Using computer-assisted factor analysis, we have shown that according to these 30 parameters TBE patients are similar to patients with multiple sclerosis and systemic lupus erythematosus. The results provide grounds for using data on blood plasma LPs as additional criteria for diagnosis of TBE.  相似文献   
8.
A comparison of relative levels of autoantibodies (Abs) to both native (n) and denatured (d) DNA in the blood of 55 patients with tick-borne encephalitis (TBE) was carried out. 31% of patients with TBE was shown to have an increased level Abs to nDNA and 40% of patients demonstrate increased level of Abs to dDNA. The percent of TBE patients with increased concentration of anti-nDNA Abs higher then that in patients with multiple sclerosis (18%) and some other autoimmune diseases (6-18%), but comparable with that for patients with systemic lupus erythematosus (38%) and polymyositis (42%). In contrast to patients with systemic lupus erythematosus and multiple sclerosis, the level of Abs to nDNA in patients with TBE is higher than the level of Abs to dDNA. Correlation coefficients of Ab levels to both n- and dDNA were estimated for group of patients in whole and for separate subgroups with different type of disease (temperature reaction, feverishness and meningitis). Analysis of correlation between titres of anti-DNA Abs and three standard biochemical markers of TBE (activity of aspartate- and alanine-aminotransferases, and concentration of whole bilirubin) for 22 patients with TBE was carried out. Statistically significant correlation was revealed only between the level of Abs to nDNA and activities of aspartate- and alanine-aminotransferases, correlation coefficients are equal to +0.44 and +0.48, respectively.  相似文献   
9.
The relative levels of autoantibodies to native and denatured DNA (nDNA and dDNA, respectively) in the blood were compared in 55 patients with tick-borne encephalitis (TBE). Compared to healthy donors, the titers of antibodies (Ab) to nDNA and dDNA were significantly higher in 31% and 40% of TBE patients, respectively. The proportion of patients with an increased concentration of anti-nDNA Ab in the case of TBE (32%) was higher than among patients with multiple sclerosis (18%) and some other autoimmune diseases (6–18%) but comparable with that among patients with systemic lupus erythematosus (38%) and polymyositis (42%). In contrast to the patients with systemic lupus erythematosus and multiple sclerosis, the level of antibodies to nDNA in TBE patients was higher than that of anti-dDNA Ab. The coefficients of correlation between the levels of Ab to nDNA and dDNA were estimated for the entire group of TBE patients and for subgroups with different forms of the disease (temperature reactions, febrile form, and meningeal form). Analysis of correlation between the anti-DNA antibody titers and three standard biochemical markers of TBE (aspartate aminotransferase and alanine aminotransferase activities and total bilirubin) was carried out for 22 patients. A statistically significant correlation was revealed only between the level of Ab to nDNA and the marker enzyme activities, with the respective correlation coefficients being +0.44 and +0.48, respectively.  相似文献   
10.
DNase autoantibodies (Abzs) can be found in the blood of patients with several autoimmune diseases, while the blood of healthy donors or patients with diseases with an insignificant disturbance of the immune status does not contain DNase Abzs. Here we present the first analysis of the DNase Abzs activity in the patients with tick-borne encephalitis (TBE). Several strict criteria have been applied to show that the DNase activity is an intrinsic property of IgGs from the sera of TBE patients but not from healthy donors. The relative activity of IgGs has been shown to vary extensively from patient to patient, but most of the preparations (91%) had detectable levels of the DNase activity. Polyclonal DNase IgGs were not active in the presence of EDTA or after a dialysis against EDTA, but could be activated by several externally added metal ions, with the level of activity decreasing in the order Mn2+ + Ca2+ ≥ Mn2++ Mg2+ ≥ Mn2+ ≥ Mg2+ + Ca2+ ≥ Co2+ ≥ Mg2+ > Ca2+, while K+, Na+, Ni2+, Zn2+, and Cu2+ did not stimulate DNA hydrolysis. Affinity chromatography on DNA-cellulose separated the DNase IgGs into many subfractions with various affinities for DNA and very different levels of the relative activity. Possible reasons for catalytic diversity of polyclonal human Abzs are discussed.  相似文献   
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