الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Gastrointestinal diseases of infectious origin usually arise upon ingestion of contaminated foods or water and can have a wide number of etiological agents, known as enteric pathogens. Among them, the genus Salmonella is of particular clinical relevance in both developed and developing countries.
from September 2016, the prevalence of Salmonella spp were investigated in 148 food and patients stools samples from the Ministry of Health Laboratory and from the patients stool along their courses at Health Insurance Hospitals and local markets, Egypt. The molecular investigation of Salmonella serovars (typhimurium, Enteritidis, Newport, Derby, Senftenberg and Virchow) widely refer to that occurrence of invA, avrA and stn within the most virulence genes associated with Salmonella pathogenicity islands (SPIs).
The total RNA concentrations were significantly increased from zero to 9.82 μg/μl by temperature increasing. However, the growth at 5°C has shown RNA considerable stabilized in total RNA concentrations as 1.1 μg/μl,
The integrity between the total RNA concentrations and growth rates were calculated to achieve the increasing levels of RNA activity by temperature elevation during S. typhimurium growth. Almost 4 fold up-regulation in stn target gene on the exponential phase, while an increasing by 2 fold was observed for it on stationary phase at room temperature. Also, considerable up-regulation was observed by 5 and 9 fold on exponential phase throughout at 35 and 40°C, respectively of exposure temperature after that down-regulation was observed by 3 and 7-fold on stationary phase at 35 and 40°C, respectively during exposure period. As expected, the differential expression of stn gene wasn’t detectible within the pattern of target genes by comparison with house keeping gene control (Ct) values at -20°C and did not show any significance difference at 5°C, this data confirmed that stn gene was consistent across the triggered by exposure of low temperature. Almost seven fold up-regulation in stn genes on the exponential phase, whereas four fold up-regulation was obtained on stationary phase of the growth at room temperature. Also, considerable up-regulation
was observed by 9 and 13-fold on exponential phase of growth throughout 35 and 40°C, respectively of exposure temperature after that down-regulation was observed by 5 and 9-fold on stationary phase of growth at 35 and 40°C, respectively during exposure period.
On other side, the differential expression of stn gene wasn’t detectible within the pattern of target genes by comparison with house keeping gene control (Ct) values at -20°C and did not show any significance difference at 5°C, this repeated data confirmed that stn gene was consistent across the triggered by exposure of low temperature. Almost 13-fold up-regulation in stn genes was observed on the exponential phase, whereas 9-fold increase was observed for them on stationary phase of growth at room temperature. Also, considerable up-regulation was observed by 17 and 21-fold on exponential phase throughout 35 and 40°C, respectively of exposure temperature after that down-regulation was observed by 10 and 15-fold on stationary phase at 35 and 40°C, respectively during exposure period. The expression pattern of stn gene of S. typhimurium was similar when contact with animal cells (RBCs) and (IEC-6) at various temperature. Moreover, it remained up-regulated from 12 to 24 h of growth (exponential phase) and sometimes elongated to more than 24 h (stationery phase), thereafter down regulation was observed after 36 h (decline phase) of growth. The up-regulated expression values were significally increased when contact with (RBCs) and approximately duplicated when contact with (IEC-6) as indication for the specificity of Salmonella with these type of animal cells which to be similar to the in nature vivo condition.