Visual detection technique for efficient screening and isolation of Salmonella based on a novel enrichment assay using chromatography membrane.

To detect Salmonella more efficiently and isolate strains more easily, a novel and simple detection method that uses an enrichment assay and two chromogenic reactions on a chromatography membrane was developed. Grade 3 chromatography paper is used as functionalized solid phase support (SPS), which contains specially optimized medium. One reaction for screening is based on the sulfate-reducing capacity of Salmonella. Hydrogen sulfide (H2S) generated by Salmonella reacts with ammonium ferric citrate to produce black colored ferrous sulfide. Another reaction is based on Salmonella C8 esterase that is unique for Enterobacteriaceae except Serratia and interacts with 4-methylumbelliferyl caprylate (MUCAP) to produce fluorescent umbelliferone, which is visible under ultraviolet light. A very low detection limit (10(1) CFU ml(-1)) for Salmonella was achieved on the background of 10(5) CFU ml(-1) Escherichia coli. More importantly, testing with more than 1,000 anal samples indicated that our method has a high positive detection rate and is relatively low cost, compared with the traditional culture-based method. It took only 1 day for the preliminary screening and 2 days to efficiently isolate the Salmonella cells, indicating that the new assay is specific, rapid, and simple for Salmonella detection. In contrast to the traditional culture-based method, this method can be easily used to screen and isolate targeted strains with the naked eye. The results of quantitative and comparative experiments showed that the visual detection technique is an efficient alternative method for the screening of Salmonella spp. in many applications of large-sized samples related to public health surveillance.

LncRNA LINC01116 competes with miR-145 for the regulation of ESR1 expression in breast cancer.

OBJECTIVE: To investigate the biological role and clinical significance of long non-coding RNAs (lncRNA) LINC01116 in breast cancer. MATERIALS AND METHODS: In the public database Gene Expression Omnibus (GEO), the breast cancer data set GSE54002 was screened for differentially expressed lncRNA LINC01116 in breast cancer tissues and paracancerous tissues. Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of LINC01116 in 64 breast cancer tissues and 30 normal breast tissues. Level of LINC01116 and clinicopathological parameters of breast cancer were statistically analyzed. The effect of LINC01116 in breast cancer cells was investigated after knockdown of LINC01116. Luciferase reporter gene was further used to investigate the mechanism of endogenous RNA (ceRNA). RESULTS: Results of GSE54002 showed that the expression of LINC01116 in breast cancer tissues was significantly increased. In clinical samples, the level of LINC01116 in patients with breast cancer was significantly increased, which was correlated with the overall survival, tumor size and tumor node metastasis (TNM) stage in patients, but not correlated with the age, sex and lymph node metastasis (p>0.05). LINC01116 can act as an endogenous sponge and bind directly to miR-145, resulting in the up-regulation of estrogen receptor 1 (ESR1), a target gene of miR-145. CONCLUSIONS: LncRNA LINC01116 is highly expressed in breast cancer and is a new prognostic biomarker in breast cancer. Our study establishes a new link between LINC01116, miR-145 and ESR1.