Prevalence of Salmonella Typhi, Staphylococcus aureus and intestinal parasites among male food handlers in Laghouat Province, Algeria

Background: Food-borne diseases are a global public health problem, most especially in developing countries. Food handlers with a low level of  personal hygiene may be colonized or infected by a wide range of enteric pathogenic micro-organisms including intestinal parasites and bacteria.  The aim of this study is to determine the prevalence of Salmonella Typhi, Staphylococcus aureus and intestinal parasites among male food handlers  in Laghouat province, southern Algeria. Methodology: In this cross-sectional study, stool samples and fingernail samples of both hands were collected from 155 randomly selected male  food handlers. Stool specimens were examined by direct wet mount, formalinether concentration, xenic invitro culture and staining methods for  parasitological identification. For bacterial isolation, standard culture media including Hektoen agar, Salmonella-Shigella (SS), Mannitol salt, and  Blood agar plates were used. Conventional biochemical tests were used for identification of S. Typhi and S. aureus. Antimicrobial susceptibility test  (AST) was performed for bacterial isolates by the Kirby-Bauer disk diffusion method. Data analysis was done using Minitab version 19 software, and  Pearson’s Chi-square test was used to determine association between categorical variables. P value < 0.05 was considered statistically significant.   Results: The overall prevalence rate of intestinal parasites among the study subjects was 40% (62/155). Blastocystis spp was the most frequent  parasite isolated (16.8%), followed by Giardia intestinalis (8.4%), Entamoeba histolytica/dispar (7.7%), Entamoeba coli (3.2%), Trichomonas intestinalis  (2.6%) and Endolimax nana (1.3%). Stool cultures revealed 4 (2.6%) positive samples for S. Typhi, and S. aureus was isolated from fingernail contents  of 23 (14.8%) subjects. All S. Typhi isolates were sensitive to imipenem and ciprofloxacin while S. aureus isolates show high sensitivity to  pristinamycin. Hand washing with soap, finger nail status and clinical manifestations were significantly associated with intestinal parasitic infections,  while clinical manifestation was the only factor associated with S. aureus infection. Conclusion: The present study indicates a high prevalence of pathogenic micro-organisms among male food handlers which highlight the important role of food handlers in the spread and transmission of foodborne infections, and thus requires more attention

Cavity optomechanics on a microfluidic resonator with water and viscous liquids

Currently, optical- or mechanical-resonances are commonly used in microfluidic research. However, optomechanical oscillations by light pressure were not shown with liquids. This is because replacing the surrounding air with water inherently increases the acoustical impedance and hence the associated acoustical radiation-losses. Here, we bridge between microfluidics and optomechanics by fabricating hollow bubble resonators with liquid inside and optically exciting 100-MHz vibrations with only mW optical-input power. This constitutes the first time that any microfluidic system is optomechanically actuated. We further prove the feasibility of microfluidic optomechanics on liquids by demonstrating vibrations on organic fluids with viscous-dissipation higher than blood viscosity while measuring density changes in the liquid via the vibration frequency shift. Our device will enable using cavity optomechanics for studying non-solid phases of matter

Atrial arrhythmogenicity in aged Scn5a+/∆KPQ mice modeling long QT type 3 syndrome and its relationship to Na+ channel expression and cardiac conduction

Recent studies have reported that human mutations in Nav1.5 predispose to early age onset atrial arrhythmia. The present experiments accordingly assess atrial arrhythmogenicity in aging Scn5a+/∆KPQ mice modeling long QT3 syndrome in relationship to cardiac Na+ channel, Nav1.5, expression. Atrial electrophysiological properties in isolated Langendorff-perfused hearts from 3- and 12-month-old wild type (WT), and Scn5a+/∆KPQ mice were assessed using programmed electrical stimulation and their Nav1.5 expression assessed by Western blot. Cardiac conduction properties were assessed electrocardiographically in intact anesthetized animals. Monophasic action potential recordings demonstrated increased atrial arrhythmogenicity specifically in aged Scn5a+/ΔKPQ hearts. These showed greater action potential duration/refractory period ratios but lower atrial Nav1.5 expression levels than aged WT mice. Atrial Nav1.5 levels were higher in young Scn5a+/ΔKPQ than young WT. These levels increased with age in WT but not Scn5a+/ΔKPQ. Both young and aged Scn5a+/ΔKPQ mice showed lower heart rates and longer PR intervals than their WT counterparts. Young Scn5a+/ΔKPQ mice showed longer QT and QTc intervals than young WT. Aged Scn5a+/ΔKPQ showed longer QRS durations than aged WT. PR intervals were prolonged and QT intervals were shortened in young relative to aged WT. In contrast, ECG parameters were similar between young and aged Scn5a+/ΔKPQ. Aged murine Scn5a+/ΔKPQ hearts thus exhibit an increased atrial arrhythmogenicity. The differing Nav1.5 expression and electrocardiographic indicators of slowed cardiac conduction between Scn5a+/ΔKPQ and WT, which show further variations associated with aging, may contribute toward atrial arrhythmia in aged Scn5a+/ΔKPQ hearts

What Every Business Student Needs to Know About Information Systems

Whether Information Systems should or should not be part of the core business school curriculum is a recurring discussion in many universities. In this article, a task force of 40 prominent information systems scholars address the issue. They conclude that information systems is absolutely an essential body of knowledge for business school students to acquire as well as a key element of the business school\u27s long-run strategic positioning within the university. Originally prepared in response to draft accreditation guidelines prepared by AACSB International, the article includes a compilation of the concepts that the authors believe to be the core information systems knowledge that all business school students should be familiar with