Self-assembled multi-ring formations of glutamine and a possible link to erythema gyratum repens

Pathogenesis of annular lesions: Why a ring presentation?

Annular lesions represent a distinct morphology which characterizes many well-known dermatologic conditions. Little is definitively known regarding the pathogenesis of annular lesions, however there a few well-regarded hypotheses. Lesions that clear centrally while enlarging peripherally may result from a local central tissue anergy, or tolerance. The central area in lesions due to dermatophyte infections or subacute cutaneous lupus erythematous may have a central immunity to the antigen that trigged the lesion. The peripheral spread of inflammatory mediators may also contribute to lesions that expand centrifugally. In a highly active immune response, some of the inflammatory mediators may spread to adjacent tissue, which can propagate the inflammatory reaction. The additional hypotheses regarding pathogenesis are disease specific with individual mechanisms having been proposed. This chapter will describe both general and disease specific mechanisms that may contribute to the formation of annular lesions.

Erythema Gyratum Repens Associated With Diffuse B-cell Lymphoma-Report of A Rare Case

Erythema gyratum repens (EGR) is a rare paraneoplastic dermatosis known to be associated with internal malignancy. Herein, we report a case of EGR with diffuse large B-cell lymphoma (DLBCL) in a young farmer who presented with generalized massive lymphadenopathy and wood-grain pattern dermatosis. Lymph node biopsy with immunohistochemistry established the diagnosis of DLBCL. He was managed by the oncologist with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) regimen which alleviated his symptoms considerably after completion of three cycles and was under follow-up.

Experimental verification of nanofluid shear-wave reconversion in ultrasonic fields

Here we present the verification of shear-mediated contributions to multiple scattering of ultrasound in suspensions. Acoustic spectroscopy was carried out with suspensions of silica of differing particle sizes and concentrations in water to find the attenuation at a broad range of frequencies. As the particle sizes approach the nanoscale, commonly used multiple scattering models fail to match experimental results. We develop a new model, taking into account shear mediated contributions, and find excellent agreement with the attenuation spectra obtained using two types of spectrometer. The results determine that shear-wave phenomena must be considered in ultrasound characterisation of nanofluids at even relatively low concentrations of scatterers that are smaller than one micrometre in diameter.