Mark Riddle

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Campylobacter jejuni remains a major cause of bacterial diarrhea worldwide and is associated with numerous sequelae, including Guillain Barré Syndrome, inflammatory bowel disease, reactive arthritis, and irritable bowel syndrome. C. jejuni is unusual for an intestinal pathogen in its ability to coat its surface with a polysaccharide capsule (CPS). These(More)
Volunteer challenge with enterotoxigenic Escherichia coli (ETEC) has been used for four decades to elucidate the pathogenesis and immune responses and assess efficacy of various interventions. We performed a systematic review of these studies and a meta-analysis of individual patient-level data (IPD) from a subset of studies using standard methodology. We(More)
BACKGROUND Shigella flexneri 2a lipopolysaccharide 50 is a nasally delivered subunit vaccine consisting of a macromolecular complex composed of LPS, IpaB, IpaC and IpaD. The current study examined vaccine safety and immunogenicity across a dose range and the clinical performance of a new intranasal delivery device. METHODS Volunteers (N=36) were(More)
BACKGROUND Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) symptoms often overlap. In some IBS cases there are subtle inflammatory changes similar to the immune-mediated pathophysiology of IBD, and the risk of both increases after infectious gastroenteritis (IGE). METHODS To evaluate the effect of IBS and IGE on IBD risk utilizing US(More)
BACKGROUND The US CDC estimates over 2 million foodborne illnesses are annually caused by 4 major enteropathogens: non-typhoid Salmonella spp., Campylobacter spp., Shigella spp. and Yersinia enterocoltica. While data suggest a number of costly and morbid chronic sequelae associated with these infections, pathogen-specific risk estimates are lacking. We(More)
We summarize the first major effort to use analytics for preemptive maintenance and repair of an electrical distribution network. This is a large-scale multi-year effort between scientists and students at Columbia and MIT and engineers from Con Edison, which operates the world's oldest and largest underground electrical system. Con Edison's preemptive(More)
BACKGROUND/AIMS Recent studies reveal that acute gastroenteritis can precipitate irritable bowel syndrome (IBS) symptoms leading to the concept of post-infectious IBS. However, the overall contribution of gastroenteritis to the total IBS prevalence is unknown. In this exercise we try to estimate the contribution of gastroenteritis in IBS using the published(More)
BACKGROUND Psychological disorders have been associated with irritable bowel syndrome (IBS) for decades in the absence of other objective etiology. However, such associations are also evident in other chronic diseases with more clearly defined pathogenesis such as ulcerative colitis. In this study, we examined the prevalence and severity of psychological(More)
BACKGROUND Reactive arthritis (ReA) is a recognized sequela of infectious gastroenteritis (IGE). However, the population-based incidence of IGE-related ReA is poorly defined, and the risk of disease has not previously been characterized in a military population. The intent of this study was to provide estimates of the incidence and morbidity associated with(More)