Evaluation of Optical Coherence Tomography as a Means of Identifying Earlier Stage Basal Cell Carcinomas while Reducing the Use of Diagnostic Biopsy.

OBJECTIVE: To determine the diagnostic accuracy of optical coherence tomography for basal cell carcinoma and the proportion of biopsies that could be avoided if optical coherence tomography is used to rule-in surgery. DESIGN: Multicenter, prospective, observational study. SETTING: Dermatology clinics. PARTICIPANTS: Consecutive patients with clinically challenging pink lesions suspicious for basal cell carcinoma. MEASUREMENTS: Clinical, dermoscopic, and optical coherence tomography images were obtained for all subjects. At each stage, the clinician made a diagnosis (pathology + subtype if applicable), and assessed his/her own confidence in the diagnosis. RESULTS: Optical coherence tomography significantly (p<0.01) improved sensitivity and specificity over clinical or dermoscopic evaluation. The percentage of correct diagnoses was 57.4 percent (clinical), 69.6 percent (dermoscopy), and 87.8 percent (optical coherence tomography). Optical coherence tomography significantly increased the certainty of diagnosis; clinicians indicated they were certain (>95% confident) in 17 percent of lesions examined clinically, in 38.6 percent examined with dermoscopy, and in 70 percent examined with optical coherence tomography. With the use of optical coherence tomography in the diagnosis of basal cell carcinoma, more than 1 in 3 patients could avoid a diagnostic biopsy. CONCLUSION: In a population of clinically challenging lesions, optical coherence tomography improved diagnostic certainty by a factor of four over clinical examination alone and improved diagnostic accuracy by 50 percent (57-88%). The addition of optical coherence tomography to other standard assessments can improve the false-positive rate and give a high degree of certainty for ruling in a positive diagnosis for basal cell carcinoma. A reduction of 36 percent in overall biopsies could be achieved by sending high certainty basal cell carcinoma positive optical coherence tomography diagnoses straight to surgery.

A bacterial type III secretion-based delivery system for functional assays of fungal effectors in cereals.

Large numbers of candidate effectors are being identified by genome sequencing of fungal pathogens and in planta expression studies. These effectors are both a boon and a curse for pathogens as they modulate the host cellular environment or suppress defense response to allow fungal growth as well as become targets of plant resistance (R) proteins. Recognition of a fungal effector by a plant R protein triggers a hypersensitive reaction (HR) leading to death of plant cells in and around the infection site, thus preventing further proliferation of the pathogen. Such HR induction has been used as an indicator of effector activity in functional assays of candidate effectors in dicots based on Agrobacterium-mediated transient expression. However, the Agrobacterium assay is not functional in cereal leaves. We therefore have adapted an alternative assay based on effector protein delivery using the type III secretion system (T3SS) of a non-pathogenic Pseudomonas spp. for use in wheat and other cereals. Here, we describe protocols for delivery of effector proteins into wheat and barley cells using the AvrRpm1 T3SS signal in the engineered non-pathogenic Pseudomonas fluorescens strain Effector-to-Host Analyzer (EtHAn). For ease of making expression clones we have generated the GATEWAY cloning compatible vectors. A calmodulin-dependent adenylate cyclase (Cya) reporter protein can be used as an effective marker for fusion protein delivery into wheat and barley by this system.