Application of ultrafast gold luminescence to measuring the instrument response function for multispectral multiphoton fluorescence lifetime imaging.

When performing multiphoton fluorescence lifetime imaging in multiple spectral emission channels, an instrument response function must be acquired in each channel if accurate measurements of complex fluorescence decays are to be performed. Although this can be achieved using the reference reconvolution technique, it is difficult to identify suitable fluorophores with a mono-exponential fluorescence decay across a broad emission spectrum. We present a solution to this problem by measuring the IRF using the ultrafast luminescence from gold nanorods. We show that ultrafast gold nanorod luminescence allows the IRF to be directly obtained in multiple spectral channels simultaneously across a wide spectral range. We validate this approach by presenting an analysis of multispectral autofluorescence FLIM data obtained from human skin ex vivo.

Phototherapy in the treatment of acne vulgaris: what is its role?

Acne vulgaris is a common dermatosis affecting 80% of the population. To date, different treatments have been used to manage this condition. Antibacterials and retinoids are currently the mainstay of treatment for acne, but their success rate varies. Phototherapy is emerging as an alternative option to treat acne vulgaris. Studies examining the role of different wavelengths and methods of light treatment have shown that phototherapy with visible light, specifically blue light, has a marked effect on inflammatory acne lesions and seems sufficient for the treatment of acne. In addition, the combination of blue-red light radiation seems to be superior to blue light alone, with minimal adverse effects. Photodynamic therapy has also been used, even in nodular and cystic acne, and had excellent therapeutic outcomes, although with significant adverse effects. Recently, low energy pulsed dye laser therapy has been used, and seems to be a promising alternative that would allow the simultaneous treatment of active acne and acne scarring. Further studies are needed to clarify the role of phototherapy as a monotherapy or an adjuvant treatment in the current management of acne vulgaris.

Langerhans' cell histiocytosis in an adult patient manifested as recurrent skull lesions and Diabetes Insipidus.

We describe a 57-year old female with the diagnosis of skull and meningeal Langerhans' cell histiocytosis who was treated with the combination of azathioprine and methotrexate. Although the skull lesions improved considerably on this regimen, the patient developed diabetes insipidus while the anterior pituitary function remained intact.