Hydroxyzine-induced priapism

Priapism is a severe urologic condition requiring emergency management. Ischemic priapism is the most common subtype which is characterized by a long-lasting, painful, and rigid erection which can be caused by medications with alpha-adrenergic properties such as hydroxyzine. Typically, medication-induced priapism is reported at therapeutic doses and few case reports exist implicating medication overdose as the cause. We report a case of a patient taking hypercompliant doses of hydroxyzine hydrochloride for worsening insomnia (200-600 mg), including the night before admission. Blood-gas analysis of blood from the right corpora was completed and revealed a pH of 6.736, pCO2 of 147, HCO3 of 18.6 and a base excess of 17.7. The patient required aspiration and 560 μg of intracavernosal phenylephrine to achieve sustained detumescence. Emergency physicians should be aware of this risk as priapism is a medical emergency and this is the first report with hydroxyzine after an intentional overdose to our knowledge

Two-Photon Absorption in CdSe Colloidal Quantum Dots Compared to Organic Molecules

We discuss fundamental differences in electronic structure as reflected in one- and two-photon absorption spectra of semiconductor quantum dots and organic molecules by performing systematic experimental and theoretical studies of the size-dependent spectra of colloidal quantum dots. Quantum-chemical and effective-mass calculations are used to model the one- and two-photon absorption spectra and compare them with the experimental results. Currently, quantum-chemical calculations are limited to only small-sized quantum dots (nanoclusters) but allow one to study various environmental effects on the optical spectra such as solvation and various surface functionalizations. The effective-mass calculations, on the other hand, are applicable to the larger-sized quantum dots and can, in general, explain the observed trends but are insensitive to solvent and ligand effects. Careful comparison of the experimental and theoretical results allows for quantifying the range of applicability of theoretical methods used in this work. Our study shows that the small clusters can be in principle described in a manner similar to that used for organic molecules. In addition, there are several important factors (quality of passivation, nature of the ligands, and intraband/interband transitions) affecting optical properties of the nanoclusters. The larger-size quantum dots, on the other hand, behave similarly to bulk semiconductors, and can be well described in terms of the effective-mass models