Single-shot dual-wavelength interferometric microscopy.

Interferometric microscopy (IM) can provide complex field information of the biological samples with high spatial and temporal resolution with virtually no photodamage. Measuring wavelength-dependent information in particular has a wide range of applications from cell and tissue refractometry to the cellular biophysical measurements. IM measurements at multiple wavelengths are typically associated with a loss in temporal resolution, field of view, stability, sensitivity, and may involve using expensive equipment such as tunable filters or spatial light modulators. Here, we present a novel and simple design for an interferometric microscope that provides single-shot off-axis interferometric measurements at two wavelengths by encoding the two spectral images at two orthogonal spatial frequencies that allows clean separation of information in the Fourier space with no resolution loss. We demonstrated accurate simultaneous quantification of polystyrene bead refractive indices at two wavelengths.

[What is new in basal cell carcinoma?] / Was gibt es Neues zum Basalzellkarzinom?

BACKGROUND: Basal cell carcinoma (BCC) is the most common skin cancer in fair-skinned individuals. Although lymph node or visceral metastases are observed in less than 0.5 % of all cases, BCC can have a fatal course due to its highly invasive growth pattern. OBJECTIVES: To provide a comprehensive update on diagnosis, treatment, and prevention of BCC. MATERIALS AND METHODS: We review the current literature and recommendations of the German guidelines on treatment and prevention of skin cancer. The most pertinent developments are summarized in this review article. RESULTS: The use of optical coherence tomography and reflectance confocal microscopy can significantly improve the diagnosis of BCC compared with clinical assessment and dermoscopy alone. Mohs micrographic surgery remains the therapeutic gold standard for tumors in the head and facial area and tumors with high-risk features. The application of imiquimod, 5­fluorouracil, or photodynamic therapy should be restricted to low-risk superficial tumors. Topical inhibitors of the sonic hedgehog (SHH) pathway are currently being evaluated in early clinical trials. In contrast, vismodegib and sonidegib have been approved for the systemic treatment of locally advanced and metastatic BCC with good response rates. The most common adverse events of both agents are muscle cramps, dysgeusia, diffuse alopecia, weight loss, and fatigue. In an Australian phase III trial, oral nicotinamide (vitamin B3) reduced the occurrence of new BCC by 20 % in skin cancer patients. CONCLUSIONS: Targeted therapy with SHH inhibitors has improved the prognosis of locally advanced and metastatic BCC, albeit at the cost of a significant number of adverse events.

Optical technologies for cervical neoplasia: update of an NCI program project grant.

Cervical cancer is the second most common cancer in women worldwide and the leading cause of cancer mortality in women in developing countries. In the United States, over $6 billion is spent annually in the evaluation and treatment of low-grade lesions, many of which do not develop into full-blown cancer. In developing countries, however, the chief concern is that cervical cancer goes undetected because of the cost of testing and the lack of resources and trained personnel to screen and diagnose the disease. The goal of the National Cancer Institute Program Project Grant CA82710 is to assess the emerging technologies of fluorescence and reflectance spectroscopy and quantitative cytology and histopathology for the diagnosis of cervical neoplasia. All of these technologies should decrease mortality, morbidity, and the cost of treating cervical cancer.

From micro to nano: recent advances in high-resolution microscopy.

Improving the spatial resolution of optical microscopes is important for a vast number of applications in the life sciences. Optical microscopy allows intact samples and living cells to be studied in their natural environment, tasks that are not possible with other microscopy methods (e.g. electron microscopy). Major advances in the past two decades have significantly improved microscope resolution. By using interference and structured light methods microscope resolution has been improved to approximately 100 nm, and with non-linear methods a ten times improvement has been demonstrated to a current resolution limit of approximately 30 nm. These methods bring together old theoretical concepts such as interference with novel non-linear methods that improve spatial resolution beyond the limits that were previously assumed to be unreachable.