Effects of orange juice pH on survival, urease activity and DNA profiles of Yersinia enterocolitica and Yersinia pseudotuberculosis stored at 4 degree C.

The objective of this study was to determine the survival, growth rate and possible cellular adaptation mechanisms of Y. pseudotuberculosis and Y. enterocolitica in orange juice under different pH conditions. Yersinia was inoculated in orange juice with adjusted pH levels of 3.9, 4.0, and 7.0 and stored at 4 C for 3, 24, 72 and 168 hours (h). The inter-and intra-species variation is significant to the pH and time of incubation variables (p<0.05). At 3.9 pH the CFU (colony forming units) count decreased significantly.At pH 3.9 and 4.0, Y. enterocolitica and Y. pseudotuberculosis survived for at least 30 days and 15 days, respectively. Yersinia that survived under low pH in orange juice revealed enhanced urease activity within 12 h of incubation. The attachment gene (ail) could not be detected by PCR in Y. enterocolitica from undiluted sample incubated for 24 h or longer. Moreover, the FesI-restriction profile was altered when Y. pseudotuberculosis was stored at pH 4.0 orange juice for 7 days. These results indicate that Yersinia could survive and grow at low pH and the survival mechanisms could also enable the bacteria to survive the stomach pH barrier to cause enteric infection.

Phage Ligands for Identification of Mesenchymal-Like Breast Cancer Cells and Cancer-Associated Fibroblasts.

Epithelial to mesenchymal transition (EMT) is believed to be crucial for primary tumors to escape their original residence and invade and metastasize. To properly define EMT, there is a need for ligands that can identify this phenomenon in tumor tissue and invivo. A phage-display selection screening was performed to select novel binding phage peptides for identification of EMT in breast cancer. Epithelial breast cancer cell line, MCF-7 was transformed to mesenchymal phenotype by TGF-ß treatment and was used for selection. Breast fibroblasts were used for subtractive depletion and breast cancer metastatic cell lines MDA-MB-231, T47D-shNMI were used for specificity assay. The binding peptides were identified, and their binding capacities were confirmed by phage capture assay, phage-based ELISA, immunofluorescence microscopy. The phage peptide bearing the 7-amino acid sequence, LGLRGSL, demonstrated selective binding to EMT phenotypic cells (MCF-7/TGF-ß and MDA-MB-231) as compared to epithelial subtype, MCF-7, T47D and breast fibroblasts (Hs578T). The selected phage was also able to identify metastatic breast cancer tumor in breast cancer tissue microarray (TMA). These studies suggest that the selected phage peptide LGLRGSL identified by phage-display library, showed significant ability to bind to mesenchymal-like breast cancer cells/ tissues and can serve as a novel probe/ligand for metastatic breast cancer diagnostic and imaging.

Metabolic syndrome and obesity among workers at Kanye Seventh-Day Adventist Hospital, Botswana.

INTRODUCTION: Metabolic syndrome and obesity are risk factors for developing type 2 diabetes mellitus and/or cardiovascular disease, especially stroke. There is evidence worldwide of the high prevalence of these pathologies in health care providers. OBJECTIVES: To determine the frequency of metabolic syndrome, overweight, obesity and risk of developing metabolic syndrome in workers at Kanye Seventh-day Adventist Hospital, Kanye, Botswana. METHODS: An observational and cross-sectional study. For the detection of metabolic syndrome, the criteria of the Adult Treatment Panel III were used; for obesity, the body mass index of 150 workers was applied. Data were grouped and analysed according to gender, age and type of work. RESULTS: Thirty-four per cent of the hospital's workers had metabolic syndrome, the same percentage were at high risk of developing metabolic syndrome, 28.7% were obese, and 27.3% were overweight. Female gender was found to be strongly associated with obesity and metabolic syndrome. The age group of 35-54 years was most affected. CONCLUSIONS: There is a high prevalence of obesity and metabolic syndrome among Kanye Seventh-day Adventist Hospital workers. We recommend the implementation of programmes to screen these risk factors by means of routine medical exams and improving the lifestyles of Botswana health care workers. The study findings could be the basis for future research among hospital staff and the general population.