[Analysis of international programs of the hygienic monitoring of foodborne pathogens].

The article gives an overview of information international networks of monitoring the microbiological food safety in the world. The most famous are the European Network of Food Safety (EFSN), Global network for disease surveillance, Foodborne (GFN), International Network for the determination of molecular subtypes of bacterial food patogens (PulseNet), International Network of Food Safety (INFOSAN). The network EFSN is engaged development of information database and of warning systems to assess food safety. GFN supervises of foodborne pathogens (Salmonella, Campylobacter, E. coli, S. typhi, Shigella, Listeria monocytogenes, C. botulinum) in food, biomaterials, samples of products from centers of infection. PulseNet International is a network of National and regional laboratory networks dedicated to tracking foodborne infections world-wide. Each PulseNet laboratory utilizes standardized genotyping methods and sharing information in real-time. The resulting surveillance provides early warning of foodborne disease outbreaks. The International Food Safety Authorities Network (INFOSAN) is a global network emergency contact points for communication between the INFOSAN secretariat and national food safety authorities. In Russia, the contact point in the International Network INFOSAN is Rospotrebnadzor. Microbiological food safety is estimated by testing the finished product. This measure does not reflect the level and range of microbial contamination of food, does not provide a forecast of diseases caused by food. In conclusion, reported the need for the organization of monitoring of microbial food contaminants in Russia.

[Toxicological sanitary characterization of silver nanoparticles introduced in gastrointestinal tract of rats].

Water suspensions of silver nanoparticles were introduced intragastrically to growing male Wistar rats daily for 28 days. There were studied animals mass gain, relative masses of viscera, intestinal barrier resistance against protein macromolecules, DNA oxidative damage, tissue non-protein thiol levels, first and second phase of xenobiotic detoxication system activity, lysosomal membranes stability in liver together with routine blood biochemical and hematological indices and caecal's microbiocenose state. The data testifying to possible toxic risks, connected with reaction of silver's nanoparticles is obtained.

[Detection of bacteria genus Campylobacter in poultry products by PCR method].

Researches on method PCR adaptation for detection Campylobacter spp. in poultry meat with use of two devices and kits and its comparison with a bacteriological method under characteristics of specificity and the bottom limit of definition are carried out. Higher efficiency of detection of Campylobacters to PCR in real time, than a bacteriological method, and also suitability for the purposes of the foods control of the kits intended initially for clinical diagnostics is shown. It is specified on necessity of a stage of bacteria enrichment before PCR up to a level above 10(5) CFU/g.

[Campylobacter in stool of patients with irritable bowel syndrome].

AIMS: According to recent studies prevalence of IBS among patients suffered from of acute enteric infection (AEI) reaches 30%, and 25% of them were accounted to Campylobacter infection. We studied the prevalence of Campylobacter in a feces of Russian IBS patients. METHODS: Fecal samples received from 39 patients with different types of IBS were studied. Campylobacter were detected by three different methods: culture, real time PCR with the C. jejuni-specific primers and ELISA. RESULTS: Only 7 patients from 39 reported about AEI in the past. C. jejuni in a stool was found in 2 (5%) patients: in the first patient by all three methods and in second one by PCR only. The first patient noted that she suffered from AEI 30 years ago. After two weeks confirmatory testing was positive only in the first patients, in the second one the tests were negative. CONCLUSIONS: C. jejuni in a stool was detected in 5% of patients with IBS. Further studies of a microbiota of an intestine in IBS patients using the combination of reliable microbiological and molecular techniques are badly needed.

Tolerance to antimicrobial agents and persistence of Escherichia coli and cyanobacteria.

Bacterial persistence is the tolerance of a small part of a cell population to bactericidal agents, which is attained by a suppression of important cell functions and subsequent deceleration or cessation of cell division. The growth rate is the decisive factor in the transition of the cells to the persister state. A comparative study of quickly growing Escherichia coli K-12 strain MC 4100 and cyanobacteria Synechocystis sp. PCC 6803 and Anabaena variabilis ATCC 29413 growing slowly was performed. The cyanobacterial cells, like E. coli cells, differed in sensitivity to antimicrobial substances depending on the growth phase. Carbenicillin inhibiting the synthesis of peptidoglycan, a component of the bacterial cell wall, and lincomycin inhibiting the protein synthesis gave rise to nucleoid decay in cells from exponential cultures of Synechocystis 6803 and did not influence the nucleoids in cells from stationary cultures. Carbenicillin suppressed the growth of exponential cultures and had no effect on cyanobacterial stationary cultures. A suppression of Synechocystis 6803 growth in the exponential phase by lincomycin was stronger than in the stationary phase. Similar data were obtained with cyanobacterial cells under the action of H2O2 or menadione, an inducer of reactive oxygen species production. Slowly growing cyanobacteria were similar to quickly growing E. coli in their characteristics. Persistence is a characteristic feature of cyanobacteria.