جستجوی مقالات مرتبط با کلیدواژه « Pathogenicity islands » در نشریات گروه « پزشکی »

In Thailand, garlic and turmeric have been used widely as basic spices in Thai food and traditional medicine. Previous studies reported that both of them had antibacterial activities. A few data have shown that extracts from both herbs are type 3 secretion system (T3SS) inhibitors. Therefore, this study aimed to investigate anti-T3SS in garlic and turmeric extracts and identify their specific mechanisms.

Salmonella Typhimurium containing chromosomally infusion between the gene encoding SipA effector protein and strep-tag epitope was used for the determination of anti-T3SS in garlic and turmeric extracts. The mechanism of inhibition was identified by the determination of mRNA expression of T3SS genes with semiquantitative RT-PCR.

Garlic and turmeric extracts contained T3SS inhibitory activity at the concentrations of 100 μg/mL and 75 μg/mL, respectively. These extracts reduced the ability of bacterial invasion into epithelial cell cultures. However, the effective dose of both extracts did not affect bacterial growth or toxic effects on HeLa cells. Moreover, the results from RNA transcriptional levels illustrated that these extracts suppressed the transcription of the T3SS regulation genes.

It may conclude that garlic and turmeric extracts blocked T3S activity for the secretion of effector proteins and bacterial invasion by interfering the expression of the T3SS regulatory cascade. Therefore, the extracts from garlic and turmeric might be potential sources for the development of new anti-T3SS therapeutic agents.

Pathogenic Escherichia coli is responsible for serious diseases; i.e.: Peritonitis, colitis, and urinary tract infections (UTIs) and even cancer, resulting in human morbidity and mortality. Environmental strains are increasingly spreading through food and dairy products, contributing to the pathogenetic burden of E. coli infections. This study was performed to compare phylogeny, virulence factors, pathogenicity islands (PAIs), and pathotypes in- between clinical and environmental E. coli isolates. A total of 105 clinical (72) and environmental (33) E. coli isolates were collected. All isolates were subjected to phylogenetic typing using a new quadruplex polymerase chain reaction (PCR). Wide array of virulence genes (VGs) and PAI markers were assessed for both subtypes, as well as, the distribution of different pathotypes among the phylogenetic groups. Seven phylogenetic groups were detected; clinical isolates were more prevalent in phylogenetic groups B2 (22.2%) and D (23.6%), whereas environmental isolates were in groups A (24.2%) and B1 (60.6%). Majority of VGs were higher in clinical E. coli isolates. Environmental isolates showed higher percentage of some other VGs including; stx2 and hlyA. PAI markers were widespread among both categories, showing high extra-intestinal pathogenic E. coli (ExPEC) PAIs combination in environmental isolates. Enteropathogenic E. coli (EPEC) was the most widespread pathotype in clinical isolates versus enterohemorrhagic E. coli (EHEC) in environmental ones. Escherichia coli pathogenicity armoury was not only confined to clinical isolates, but to environmental ones as well. Therefore, environmental E. coli isolates can serve as reservoirs for transmission of E. coli pathogenicity.