We describe a genome-wide gain-of-function screen for regulators of NF-kappaB, and identify Rap1 (Trf2IP), as an essential modulator of NF-kappaB-mediated pathways. NF-kappaB is induced by ectopic expression of Rap1, whereas its activity is inhibited by Rap1 depletion. In addition to localizing on telomeres, mammalian Rap1 forms a complex with IKKs (IkappaB kinases), and is crucial for the ability of IKKs to be recruited to, and phosphorylate, the p65 subunit of NF-kappaB to make it transcriptionally competent. Rap1-mutant mice display defective NF-kappaB activation and are resistant to endotoxic shock. Furthermore, levels of Rap1 are positively regulated by NF-kappaB, and human breast cancers with NF-kappaB hyperactivity show elevated levels of cytoplasmic Rap1. Similar to inhibiting NF-kappaB, knockdown of Rap1 sensitizes breast cancer cells to apoptosis. These results identify the first cytoplasmic role of Rap1 and provide a mechanism through which it regulates an important signalling cascade in mammals, independent of its ability to regulate telomere function.

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Brucellosis is a zoonotic disease endemic to much of the world. It most often presents with nonspecific symptoms and is a well known cause of undulant fever. Focal forms occur less frequently, with osteoarticular complications being the most common. In this study, we describe a rare case of brucellosis presenting as cholecystitis.

We describe an incidental Burkholderia pseudomallei laboratory exposure in Arizona, USA. Because melioidosis cases are increasing in the United States and B. pseudomallei reservoirs have been discovered in the Gulf Coast Region, US laboratory staff could be at increased risk for B. pseudomallei exposure.

Melioidosis, an infection caused by Burkholderia pseudomallei, has a very high risk of mortality when treated, with an even higher risk of fatality if undiagnosed or not treated appropriately. It is endemic to Asia, Australia, South America, and the Caribbean; however, the number of melioidosis cases reported in the United States has been increasing. Therefore, physicians should be aware of this clinical entity and its possible presentations. Mycotic aneurysms due to B. pseudomallei are extremely rare, accounting for ~1%–2% of cases. Here we describe a rare case of melioidosis presenting as a mycotic aneurysm in the United States, highlight the potential for diagnostic challenges and epidemiologic concerns, and provide a review of mycotic aneurysm cases due to B. pseudomallei published to date.

A 58-year-old man with recently diagnosed coccidioidal meningitis presented to the ED with a five-day history of headache, photopsia, blurred vision, and worsening encephalopathy. His coccidioidal meningitis had responded well to fluconazole therapy, but three weeks later, he developed acute symptomatic worsening. Unfortunately, his clinical worsening coincided with Arizona's worst seasonal West Nile Virus (WNV) outbreak. He was ultimately found to have WNV neuroinvasive disease. Concurrent coccidioidal and WNV neuroinvasive diseases have not been described in the literature. Fortunately, he improved quickly to his normal baseline without neurologic deficits with supportive therapy for his WNV neuroinvasive disease and remains on lifelong antifungal therapy for coccidioidal meningitis.

Background Despite the endemic nature of Coccidioides sp. to the American Southwest, the incidence Coccidioides sp. infective endocarditis (CIE) is rare. Following successful treatment of a patient with CIE at our institution, we reviewed the literature to identify trends in disease presentation, patient characteristics, and outcomes. Methods We reviewed all cases of CIE reported since 1938. Details including patient demographics, underlying immunodeficiency, time to diagnosis, treatment, and outcome were collected for analysis of diagnostic challenges and survival. Results Including ours, we identified 11 published cases of CIE. The majority (7) occurred in men. 5 patients were of either African American or Hispanic descent. Of the 10 patients with reported ages, the median age was 35.5 years (range 3 weeks – 61 years). 5 patients had a previous diagnosis of coccidioidomycosis and only 3 had an immunocompromising condition. These comprised pregnancy, heart transplant, and juvenile inflammatory arthritis. Three cases had multi-valvular involvement, but the majority affected the mitral (5) and the aortic (4) valves. Only 2 of the 11 cases involved a prosthetic valve. Of the 8 cases with reported blood cultures, only 2 were positive. Ten of the 11 cases had extra-cardiac disease. Complement fixation (CF) titers were heterogenous with a median of 1:32 and a range of 1:1 to 1:2048. There was no obvious correlation between a patient’s CF titer and their survival. Average time to diagnosis was 3.5 months (range 2.5 – 36 months). Diagnosis was made post-mortem in 4 of the 11 cases. 6 patients (54%) did not survive. Notably, 2 of the fatal cases preceded the discovery of amphotericin B (1969) and 4 occurred prior to the discovery of fluconazole (1990). Of the five patients that survived, four required surgical intervention in addition to azole therapy. Conclusion CIE is a diagnostic and therapeutic challenge. The diagnosis itself is rare, culture incubation times are long, and the symptoms are often non-specific thus delaying definitive therapy. The introduction of azole therapy appears to have had significant impact on rates of survival. Despite this, successful management of CIE still requires concurrent surgical intervention with aggressive, indefinite anti-fungal therapy. Disclosures All Authors: No reported disclosures