Cutaneous involvement in relapsed multiple myeloma.

Cutaneous involvement in multiple myeloma with extramedullary disease is rare. We report the case of a refractory multiple myeloma patient who developed a cutaneous lesion. Histopathology revealed dermal immature plasma cell infiltrate with a lack of CD138 expression.

Severe erosive gingivostomatitis in a patient treated by vedolizumab.

Vedolizumab is a humanized monoclonal antibody that binds to the human a4β7 integrin and is approved for use in inflammatory bowel diseases. We describe a patient with severe, refractory erosive gingivostomatitis, which appeared a few days after the first dose of vedolizumab and resolved after discontinuation of the drug. We believe the gingivostomatitis to be a direct side effect of vedolizumab, rather than an extraintestinal manifestation of the underlying inflammatory bowel diseases.

Precision Measurements in Few-Electron Molecules: The Ionization Energy of Metastable ^{4}He_{2} and the First Rotational Interval of ^{4}He_{2}^{+}.

Molecular helium represents a benchmark system for testing ab initio calculations on few-electron molecules. We report on the determination of the adiabatic ionization energy of the a ^{3}Σ_{u}^{+} state of He_{2}, corresponding to the energy interval between the a ^{3}Σ_{u}^{+} (v^{''}=0, N^{''}=1) state of He_{2} and the X^{+} ^{2}Σ_{u}^{+} (v^{+}=0, N^{+}=1) state of He_{2}^{+}, and of the lowest rotational interval of He_{2}^{+}. These measurements rely on the excitation of metastable He_{2} molecules to high Rydberg states using frequency-comb-calibrated continuous-wave UV radiation in a counterpropagating laser-beam setup.

Fundamental vibration frequency and rotational structure of the first excited vibrational level of the molecular helium ion ( ).

The term values of the rotational levels of the first excited vibrational state of the electronic ground state of with a rotational quantum number ≤ 13 have been determined with an accuracy of 1.2 × 10 cm (∼35 MHz) by multichannel-quantum-defect-theory-assisted Rydberg spectroscopy of metastable He. Comparison of the experimental term values with the most accurate results for available in the literature [W.