Detection of non-typhoid Salmonella infection by citrus and citrus extracts in Lao PDR

Objective:To know the current state of non-typhoid Salmonella infection in Laos.To examine the usefulness of new screening methods for Salmonella using citrus.Methods:Non-typhoid Salmonella infection of person in Lao PDR was studied in this research(2004-2009).The site was Vientiane capital city in 2004.Research from rural villages locating suburb of Vientiane during 2005-2008 was carried out.Rural villages in Attapu province where ethnic minorities were living was searched for this study in 2009.During this research,to detect Salmonella strain, a new method using citrus and citrus extract named MY phenomenon that observing black ring (MIDO ring) on DHL agar was tried.The slice lemon and lime were used for this trial in 2004. After 2005,disk of ascorbic acid and citric acid were used for the device instead of citrus fruits itself.Results:During this research,65 of 272 human samples(23.9%) were infected with non- typhoid Salmonella.Conclusions:During this study,the method using citrus and citrus extracts was accepted for the detection of Salmonella.This study shows that with citrus and citrus extract, detection of Salmonella is possible using only DHL media.Results suggest that infectious rate of non-typhoid Salmonella was high.

Symbiosis of <i>Salmonella</i>and <i>Escherichia coli</i>by MY Phenomenon

Background: The symbiotic relationship between E. coli and Salmonella was demonstrated using hydrogen sulfide production named MY phenomenon, which is a feature of Salmonella. Methods: In order to confirm the hydrogen sulfide production of Salmonella by iron sulfide formation, deoxycholate-hydrogen sulfate-lactose agar medium having both a sulfur source and an iron source was used. The case where Salmonella was cultured alone was compared with the case co-cultured with E. coli. In the case of culture with Salmonella alone, the MY phenomenon has not occurred. When Salmonella was co-cultured with E. coli, Salmonella cultured near E. coli existing place showed a black color named MY phenomenon. When E. coli was cultured alone, it turned red due to the organic acid produced. However, when E. coli was cultured in the part where Salmonella. is inoculated on the surface of the medium, the MY phenomenon appeared there. Furthermore, hydrogen sulfide production was more active in Salmonella co-existing with E. coli. Conclusion: The study shows an important relation that E. coli is a promoting factor for Salmonella culture by NY phenomenon. The relation suggests that bacterial symbiosis relation exist in bacterial flora.

Detection of Non-Typhoidal Salmonella Using a Mechanism for Controlling Hydrogen Sulfide Production

To know the relation between NaCl concentration and hydrogen sulfide (H2S) production by MY Phenomenon of Salmonella, we developed a method to control H2S production by Salmonella in this study. Desoxycholate-hydrogen sulfide-lactose (DHL) agar was used as the selective medium for Salmonella. Triple sugar iron (TSI) agar was used as the screening medium. Citric acid disks were placed on DHL agar. NaCl was added to both media. After 24 hours incubation, H2S production on DHL agar was stimulated by citric acid, whereas production was suppressed by adding NaCl. The color change in the bottom of the TSI medium was due to the low production of black FeS. The production of FeS was reduced by lower H2S production by Salmonella with an increasing concentration of NaCl from 0.5% to 3%. The inhibition of the black color meant that the color change due to glucose fermentation could be seen clearly in the bottom of the agar. The current method cannot detect glucose fermentation but the addition of more NaCl to the TSI medium allowed the visualization of glucose fermentation by Salmonella. Although H2S production of salmonella was promoted by citrate etc., being controlled by sodium chloride was proved in this study. Thus, we had developed a possibility of novel technique for the detection of Salmonella etc.

Targeting fructose metabolism by glucose transporter 5 regulation in human cholangiocarcinoma

Alterations in cellular metabolism may contribute to tumor proliferation and survival.Upregulation of the facilitative glucose transporter(GLUT)plays a key role in promoting cancer.GLUT5 mediates modulation of fructose utilization,and its overexpression has been associated with poor prognosis in several cancers.However,its metabolic regulation remains poorly understood.Here,we demonstrated elevated GLUT5 expression in human cholangiocarcinoma(CCA),using RNA sequencing data from samples of human tissues and cell lines,as compared to normal liver tissues or a cholangiocyte cell line.Cells exhibiting highexpression of GLUT5 showed increased rates of cell proliferation and ATP production,particularly in a fructose-supplemented medium.In contrast,GLUT5 silencing attenuated cell proliferation,ATP production,cell migration/invasion,and improved epithelialemesenchymal transition(EMT)balance.Correspondingly,fructose consumption increased tumor growth in a nude mouse xenograft model,and GLUT5 silencing suppressed growth,supporting the tumor-inhibitory effect of GLUT5 downregulation.Furthermore,in the metabolic pathways of fructolysis-Warburg effect,the expression levels of relative downstream genes,including ketohexokinase(KHK),aldolase B(ALDOB),lactate dehydrogenase A(LDHA),and monocarboxylate transporter 4(MCT4),as well as hypoxia-inducible factor 1 alpha(HIF1A),were altered in a GLUT5 expression-dependent manner.Taken together,these findings indicate that GLUT5 could be a potential target for CCA therapeutic approach via metabolic regulation.