Kerstin Helfrich

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BACKGROUND Several diagnostic laboratory methods are available for case confirmation of Buruli ulcer disease. This study assessed the sensitivity of various diagnostic tests in relation to clinical presentation of the disease, type of diagnostic specimen, and treatment history. METHODS Swab samples, 3-mm punch biopsy tissue specimens, and surgically(More)
BACKGROUND Since the early 1990s more than 1,800 patients with lesions suspicious for Buruli ulcer disease (BUD) have been reported from Togo. However, less than five percent of these were laboratory confirmed. Since 2007, the Togolese National Buruli Ulcer Control Program has been supported by the German Leprosy and Tuberculosis Relief Association (DAHW).(More)
Purpose. Up to 30% of international travelers are affected by travelers' diarrhea (TD). Reliable data on the etiology of TD is lacking. Sufficient laboratory capacity at travel destinations is often unavailable and transporting conventional stool samples to the home country is inconvenient. We evaluated the use of Hemoccult cards for stool sampling combined(More)
BACKGROUND In a previous study PCR analysis of clinical samples from suspected cases of Buruli ulcer disease (BUD) from Togo and external quality assurance (EQA) for local microscopy were conducted at an external reference laboratory in Germany. The relatively poor performance of local microscopy as well as effort and time associated with shipment of PCR(More)
In accordance with recent WHO recommendations, this study evaluates the sensitivities of PCR and microscopy for fine-needle aspiration (FNA) versus techniques involving swabs and punch biopsy specimens and suggests that FNA can replace punch biopsies for nonulcerative lesions and may serve as an alternative for ulcerative lesions in cases where scarred(More)
Due to increased migration, Chagas disease has become an international health problem. Reliable diagnosis of chronically infected people is crucial for prevention of non-vectorial transmission as well as treatment. This study compared four distinct PCR methods for detection of Trypanosoma cruzi DNA for the use in well-equipped routine diagnostic(More)
Diese Dissertation ist auf dem Hochschulschriftenserver der ULB Bonn unter Abstract Few-body effects play an important role for the understanding of ultracold quantum gases. We make use of an effective field theory approach to investigate various aspects of universal few-body physics close to a Feshbach resonance. That is the regime where the scattering(More)
PURPOSE We report two experiments that address the role of stereopsis in viewing the fundus. METHODS Thirteen observers viewed stereo slides obtained by lateral displacement of a fundus camera. We quantified the capacity of seven clinicians (normal stereopsis) to resolve depth in a model eye viewed monocularly and binocularly. We also compared the ability(More)
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