Molecular Diagnostics of Staphylococcus aureus (original) (raw)

2010, NATO Science for Peace and Security Series A: Chemistry and Biology

Then the attention was concentrated on the possible and more diffuse agents which may contaminate the food, the water and the environment and the possible methods which may be sufficient precise, rapid and easy to use on a large number of person and samples. Dr. Coenye elaborated a fast method consisting in solid-phase cytometry which permits to analyse many samples and gives the possibility to visualise few bacteria or other kind of cells also if they are in small number. The analysis was made on air samples, on water and food samples. As regards the water possible contamination of the source in relation to the particular structure of the soil was suggested by Vardanyan and Aginian. Then the study was divided in four sectors of possible contaminant: bacteria especially the more diffuse, virus, parasites and pollutants. Of each the possible way of diffusion, the consequent diseases and the more modern and safe methods used for diagnosis were presented and discussed in view of the results obtained. presence and also some chemical treatment can limit the development of these bacteria. The experiments therefore showed that the ham is practically safe as regard a possible contamination from this bacterium which is common in pig skin. The second section is dedicated to virus infection. Hepatitis B is taken in consideration for his consequence and since it is easy to diffuse not only through blood, but also through contaminated instruments, sexual contacts and to the infants from infected mother. The diagnosis is fundamental in order to prevent the diffusion, since the disease tends to be chronic and causes cirrhosis. Vaccination could prevent the illness. Another emergent viral hepatitis is that causes by E virus, a single stranded RNA virus, which is endemic in many areas like North America and Asia. It can be transmitted via the faecal-oral route, water and also food. This virus causes acute hepatitis and it is important to distinguish it from other kind of viral hepatitis. The pathogenesis of hepatitis E is not well known and the diagnosis is actually mainly serological even if a molecular method represents that preferable to be developed. Another emergent disease is due to Dengue viruses which may cause infections similar to a simple flu up to more severe syndromes like haemorrhagic fever or dengue shock syndrome. The genome of Dengue virus is formed by RNA of approximately 11 kb in length, composed by three structural genes and seven non structural protein. Since this virus does not give origin to a specific disease, it is necessary to make a precise diagnosis; at moment many methods exist, like immunological text and the authors in their article make a comparison between them. In the third section parasites have been taken in consideration an infection which can be transmitted mainly from food either vegetable or animal including fishes. A complete review of the possible parasites contamination and especially of some emerging or re-emerging ones is presented in the paper of Dei Cas and others. They first take in consideration the difference between the various geographical areas underlined the fact that these infections affect more than three millions of people in the area in which the people live with less than $2 per day. These infections are also responsible of mental and physical underdevelopment of Africa children. The most diffuse are Cryptosporidium and Giardia intestinalis which may be transmitted with the faeces of cat or domestic dog. Less diffuse but equally important for the pathological consequences are Trypanosoma cruzi and Toxoplasma gondii which are diffuse also in America and Europe. The presence of some parasites, like Diphyllibotrium, in fishes favours the contamination especially when are used not cooked such sushi or marinated fishes infected with larval plerocercoids. The diffusion is mainly in the freshwaters and in Europe especially in Switzerland and in Italian, French Alpine lake region. Schistosoma haematobium which seems responsible of urinary bladder carcinoma and S. japonicum and S. mansoni which are linked to hepatic and colorectal carcinoma. Since the way of diffusion is not well known a possible presence of parasites and the relative consequence may represent a risk. Biological pollutant are due to fungi toxic metabolites which can contaminate foods are known as micotoxins. These products are not necessary for the fungi growth and they can be present in the environment as well as in foods. Their effect on the human health depend not only by its characteristic, but also by the immune system of each person. A biosensor system is developed in order to evaluate contaminants in very simple and quick way. The results are compared with standard methods such as HPLC and ELISA. In conclusion, our analysis includes a large spectrum of diffuse contaminants which may spread mainly with foods and can be the causes of many pathologies some of them could be very severe. The development of quick and un-expensive new methods represent an help for diagnostic purposes since in many case it is necessary to analyse a large number of samples. The use of some of them to prevent bio-terrorist attack may interest a large number of people in the same time or may in some cases be responsible of chronic diseases with high mortality. It is easy to Part I Bioterrorism Prevention 3 M.V. Magni (ed.), Detection of Bacteria, Viruses, Parasites and Fungi,