A novel and functional conjugative transfer system identified in O119:H2 enteropathogenic Escherichia coli (EPEC) strain MB80 by subtractive hybridization is encoded on a large multidrug resistance plasmid, distinct from the well-described EPEC adherence factor (EAF) plasmid. Variants of the MB80 conjugative resistance plasmid were identified in other EPEC strains, including the prototypical O111:NM strain B171, from which the EAF plasmid has been sequenced. This separate large plasmid and the selective advantage that it confers in the antibiotic era have been overlooked because it comigrates with the virulence plasmid on conventional gels.Enteropathogenic Escherichia coli (EPEC) continues to be a major cause of diarrhea and death, predominantly in developing countries (8,22). During infection, EPEC strains attach intimately to the intestinal epithelium and efface the absorptive microvilli, initiating a complex signaling cascade that ultimately leads to diarrhea by mechanisms that are only partially understood (8). These pathogenic effects manifest as an "attaching and effacing" histopathological hallmark, which is conferred by a large chromosomal island called the locus of enterocyte effacement (LEE). The LEE encodes a virulence gene regulator and a type III secretion system and effectors, as well as the intimin adhesin and its translocated receptor. The LEE is present in all EPEC strains, as well as in enterohemorrhaghic E. coli and some animal pathogens (reviewed in references 8 and 22).EPEC strains are classified as being either typical or atypical based on their ability to form densely packed three-dimensional clusters, or microcolonies, a phenotype known as localized adherence (LA). LA is conferred by a large EPEC adherence factor (EAF) plasmid, associated with virulence in epidemiological and volunteer challenge studies, which is present in all typical EPEC strains and absent or altered in atypical EPEC strains (3,16,25,35). The specific virulence factor responsible for LA is an EAF plasmid-encoded bundleforming pilus (Bfp), which also contributes to antigenicity, autoaggregation, and biofilm formation (3,11,15,20). On a separate region of the EAF plasmid are the perABC genes, encoding the plasmid-encoded regulator (a transcriptional activator for the bfp operon and the LEE, as well as its own promoter) and other virulence loci (9, 19). The EAF plasmid and the LEE are believed to have been acquired by different EPEC lineages in separate horizontal events (30).EAF plasmids from two well-studied EPEC strains have been sequenced. The major difference between the EAF plasmids from isolates E2368/69 (of the EPEC1 lineage [30]) and B171 (representing the EPEC2 lineage [30]), is the presence of conjugative transfer (tra) genes on pMAR7, the E2348/69 EAF plasmid (7). The B171 EAF plasmid, pB171, does not contain tra genes (36), even though at least one earlier paper reported conjugative transfer of pB171 (31). Other than with respect to tra genes, the two sequenced EAF plasmids are highly conserved, and low-resol...

Systemic contact dermatitis (SCD) refers to a skin condition where an individual who is cutaneously sensitized to an allergen will subsequently react to that same allergen or a cross-reacting allergen via the systemic route. It occurs to allergens including metals, medications, and foods. There has been recent interest in metal allergy as it relates to the implantation of devices such as orthopedic, dental, cardiac, and gynecologic implants. This review will briefly address all causes of systemic contact dermatitis with a special and expanded focus on metal implant allergy. We present literature on SCD to various metal biomedical devices, patch testing for diagnosis of metal allergy pre and post implantation and treatment.

The gastrointestinal (GI) tract is a common site of melanoma metastases although reports of small bowel intussusception are relatively rare. Most patients with intussusception will be symptomatic and resection will provide significant palliation. In rare instances, patients will have solitary metastases to the small intestine, and resection can provide long-term palliation and chance for cure. We describe a case of a patient with a widely metastatic melanoma who presented with crampy abdominal pain and CT findings of small bowel metastases. Exploration revealed jejunojejunal intussusception and resection provided excellent palliation.

The use of cellular phones has risen exponentially with over 300 million subscribers. Nickel has been detected in cell phones and reports of contact dermatitis attributable to metals are present in the literature. We determined nickel and cobalt content in popular cell phones in the United States. Adults ( > 18 years) who owned a flip phone, Blackberry Ò , or iPhone Ò were eligible. Seventy-two cell phones were tested using SmartPractice's Ò commercially available nickel and cobalt spot tests. Test areas included buttons, keypad, speakers, camera, and metal panels. Of the 72 cell phones tested, no iPhones or Droids Ò tested positive for nickel or cobalt. About 29.4% of Blackberrys [95% confidence interval (CI), 13%-53%] tested positive for nickel; none were positive for cobalt. About 90.5% of flip phones (95% CI, 70%-99%) tested positive for nickel and 52.4% of flip phones (95% CI, 32%-72%) tested positive for cobalt. Our study indicates that nickel and cobalt are present in popular cell phones. Patients with known nickel or cobalt allergy may consider their cellular phones as a potential source of exposure. Further studies are needed to examine whether there is a direct association with metal content in cell phones and the manifestation of metal allergy.

Allergic rhinitis is a costly disease associated with significant morbidity. It impacts the quality of life of millions of individuals, particularly in industrialized nations, and it is on the rise. Lost productivity and total healthcare expenditure exceeds several billion dollars annually in the United States, with an estimate of >$6 billion spent on prescription medications alone. It is also associated with asthma and other atopic conditions, sinusitis, otitis media, and sleep apnea. Primary care physicians should be well adept at recognizing and initiating empiric first-line therapy for chronic rhinitis. Allergen avoidance, topical nasal steroids, and antihistamines may be sufficient for some patients. In most cases, referral to a board-certified allergy specialist for skin testing and targeted management is indicated. It is essential to make sure that patients abstain from using antihistamines at least 1 week prior to reporting to the allergist for skin testing in order to avoid false-negative results. Traditional subcutaneous allergen immunotherapy, when performed by an experienced allergist, affords relief in >75% of cases. The growing armament of treatment options for refractory allergic rhinitis includes oral and sublingual immunotherapy, recombinant allergens, conjugated DNA vaccines, and anti-immunoglobulin E monoclonal antibody.

Allergic contact dermatitis in children is underdiagnosed and undertreated, and its incidence is increasing. Appropriate history taking and the suspicion for allergic contact dermatitis is essential, and patch testing remains the gold standard in diagnosis. Avoidance of the offending allergen, once identified, is the first goal of treatment. Medical therapies include topical corticosteroid and topical immunomodulators. In severe cases, oral corticosteroids or immunomodulators are utilized, although prospective randomized trials for the treatment of this disease in children are lacking. A PubMed literature search was performed to identify publications on allergic contact dermatitis in the pediatric population with the keywords: dermatitis, children, allergic contact dermatitis, pediatrics, contact hypersensitivity, contact allergy, treatment, and management. This review will address the major principles behind the diagnosis and management of this disease in the pediatric population, and highlight useful strategies that may result in improved treatment of this condition.

Here, we demonstrate that high levels of IL-33 and a high IL-33/soluble ST2 ratio correlates with elevated levels of IFN-γ, TNF-α and IL-17α as well as IL-5, demonstrating that IL-33 has pleiotropic effects. However, elevated IL-33 did not significantly impact lipid accumulation in macrophages overall. Given the wide variety of cellular responses regulated by IL-33, further investigation with a larger sample size will allow us to clarify the threshold concentration of IL-33 that leads to optimal cholesterol balance.

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