Time filter

Source Type

Ahmed S.F.,Research Science Directorate | Shaheen H.I.,Research Science Directorate | Abdel-Messih I.A.,Research Science Directorate | Mostafa M.,Research Science Directorate | And 7 more authors.
Journal of Tropical Pediatrics | Year: 2014

A total of 220 enteroadherent Escherichia coli were identified from 729 Egyptian children with diarrhea using the HEp-2 adherence assay. Enteropathogenic E.coli (EPEC1/438) was common among children <6 months old and provoked vomiting, while diffuse-adhering E.coli (DAEC1/4109) induced diarrheal episodes of short duration, and enteroaggregative E.coli (EAEC1/473) induced mild non-persistent diarrhea. These results suggest that EPEC is associated with infantile diarrhea in Egyptian children. © The Author [2014].

Coutinho-Abreu I.V.,University of Notre Dame | Coutinho-Abreu I.V.,Kansas State University | Mukbel R.,University of Notre Dame | Hanafi H.A.,Research Science Directorate | And 12 more authors.
BMC Ecology | Year: 2011

Background: Sand fly saliva can drive the outcome of Leishmania infection in animal models, and salivary components have been postulated as vaccine candidates against leishmaniasis. In the sand fly Phlebotomus papatasi, natural sugar-sources modulate the activity of proteins involved in meal digestion, and possibly influence vectorial capacity. However, only a handful of studies have assessed the variability of salivary components in sand flies, focusing on the effects of environmental factors in natural habitats. In order to better understand such interactions, we compared the expression profiles of nine P. papatasi salivary gland genes of specimens inhabiting different ecological habitats in Egypt and Jordan and throughout the sand fly season in each habitat.Results: The majority of investigated genes were up-regulated in specimens from Swaymeh late in the season, when the availability of sugar sources is reduced due to water deprivation. On the other hand, these genes were not up-regulated in specimens collected from Aswan, an irrigated area less susceptible to drought effects.Conclusion: Expression plasticity of genes involved with vectorial capacity in disease vectors may play an important epidemiological role in the establishment of diseases in natural habitats. © 2011 Coutinho-Abreu et al; licensee BioMed Central Ltd.

Ahmed S.F.,Research Science Directorate | Klena J.,Research Science Directorate | Husain T.,Research Science Directorate | Monestersky J.,Research Science Directorate | And 2 more authors.
Annals of Clinical Microbiology and Antimicrobials | Year: 2013

Background: Shigella flexneri serotype 1c emerged as a critical isolate from children in Egypt and Pakistan. The pattern of antimicrobial susceptibility (AMS) and resistance genes of this serotype have yet to be characterized.Findings: Sixty nine S. flexneri 1c isolates isolates were identified from both Egypt (n-46) and Pakistan (n = 23) and tested for AMS by disk diffusion method and minimal inhibitory concentrations were also determined. Isolates were genotyped by pulsed field gel electrophoresis (PFGE) and five relevant resistance genes (blaTEM, blaSHV, blaOXA, sulI and sulII) were detected by polymerase chain reaction (PCR) and confirmed by DNA sequencing. High resistance was observed in all isolates for ampicillin (AM >96%); trimethoprim-sulphamethoxazole and tetracycline (>88%). Most AM-resistant isolates from Egypt (70%) harbored blaTEM resistance, while 52% of isolates from Pakistan expressed blaOXA. All isolates were closely related by PFGE, irrespective of source or time of collection. The sulII gene was present in 100% of isolates from pediatric cases in Egypt, 65% of Pakistan isolates, and 53% of isolates from older Egyptian patients.Conclusions: While different Shigella serotypes gathered in specific genotypic groups, 1c serotype isolates formed multiple clusters. Although AMS was considerably high to most commonly used drugs, genetic determinants were variable between countries over time. The data stress the need for a more careful selection of antibiotics in the treatment of shigellosis. © 2013 Ahmed et al.; licensee BioMed Central Ltd.

Geraci N.S.,University of Notre Dame | Mukbel R.M.,University of Notre Dame | Kemp M.T.,University of Notre Dame | Wadsworth M.N.,University of Notre Dame | And 13 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2014

Phlebotomus papatasi sand flies are among the primary vectors of Leishmania major parasites from Morocco to the Indian subcontinent and from southern Europe to central and eastern Africa. Antibody-based immunity to sand fly salivary gland proteins in human populations remains a complex contextual problem that is not yet fully understood. We profiled the immunoreactivities of plasma antibodies to sand fly salivary gland sonicates (SGSs) from 229 human blood donors residing in different regions of sand fly endemicity throughout Jordan and Egypt as well as 69 US military personnel, who were differentially exposed to P. papatasi bites and L. major infections in Iraq. Compared with plasma from control region donors, antibodies were significantly immunoreactive to five salivary proteins (12, 26, 30, 38, and 44 kDa) among Jordanian and Egyptian donors, with immunoglobulin G4 being the dominant anti-SGS isotype. US personnel were significantly immunoreactive to only two salivary proteins (38 and 14 kDa). Using k-means clustering, donors were segregated into four clusters distinguished by unique immunoreactivity profiles to varying combinations of the significantly immunogenic salivary proteins. SGS-induced cellular proliferation was diminished among donors residing in sand fly-endemic regions. These data provide a clearer picture of human immune responses to sand fly vector salivary constituents. Copyright © 2014 by The American Society of Tropical Medicine and Hygiene.

Discover hidden collaborations