Evidence for Nevirapine Bioactivation in Man: Searching for the First Step in the Mechanism of Nevirapine Toxicity

Despite its efficacy, including in the prevention of vertical transmission, the antiretroviral nevirapine is associated with severe idiosyncratic hepatotoxicity and skin rash. The mechanisms underlying nevirapine toxicity are not fully understood, but drug bioactivation to reactive metabolites capable of forming stable protein adducts is thought to be involved. This hypothesis is based on the paradigm that drug reactive metabolites have the potential to bind to self-proteins, which results in drug-modified proteins being perceived as foreign by the immune system. The aim of the present work was to identify hemoglobin adducts in HIV patients as biomarkers of nevirapine haptenation upon bioactivation. The ultimate goal is to develop diagnostic methods for predicting the onset of nevirapine-induced toxic reactions. All included subjects were adults on nevirapine-containing antiretroviral therapy for at least 1month. The protocol received prior approval from the Hospital Ethics Committees and patients gave their written informed consent. Nevirapine-derived adducts with the N-terminal valine of hemoglobin were analyzed by an established liquid chromatography-electrospray ionization-tandem mass spectrometry method and characterized on the basis of retention time and mass spectrometric fragmentation pattern by comparison with adduct standards prepared synthetically. The nevirapine adducts were detected in 12/13 patient samples, and quantified in 11/12 samples (2.58±0.8 fmol/g of hemoglobin). This work represents the first evidence of nevirapine-protein adduct formation in man and confirms the ability of nevirapine to modify self-proteins, thus providing clues to the molecular mechanisms underlying nevirapine toxicity. Moreover, the possibility of assessing nevirapine-protein adduct levels has the potential to become useful for predicting the onset of nevirapine-induced adverse reactions.

The Role of Propranolol in the Treatment of Infantile Hemangioma

INTRODUCTION: Infantile hemangioma (IH) is one of the most common childhood tumors. There are various medical or surgical therapeutic options, all with suboptimal results. Recently, the successful use of propranolol for involution of IH was described. We report the results of a single-center experience with this therapeutic option. OBJECTIVE: To prospectively assess the efficacy and safety of propranolol in children with infantile hemangioma. METHODS: We performed a prospective analysis of clinical data of all patients with IH referred to a pediatric cardiology center for baseline cardiovascular assessment prior to propranolol therapy. Propranolol was given at a starting dose of 1 mg/kg/day and titrated to a target dose of 2-3 mg/kg/day according to clinical response. Efficacy was assessed through a photograph-based severity scoring scale. Safety was assessed by collecting data regarding significant side effects. RESULTS: Starting in 2010, 30 patients (15 female) were referred for propranolol treatment of IH, at a median age of six months (1-63 months). The mean target propranolol dose was 2.8 mg/kg/day, with a mean duration of therapy of 12 months. All patients experienced significant reduction of IH size and volume. There were no side effects. CONCLUSIONS: In our experience propranolol appears to be a useful and safe treatment option for severe or complicated IH, achieving a rapid and significant reduction in their size. No adverse effects were observed, although until larger clinical trials are completed, potential adverse events should be borne in mind and consultation with local specialists is recommended prior to initiating treatment.

The Support Role in Clinical Supervision of Nursing Students: Determinant in the Development of Emotional Skills

The problematic situation faced by clients, associated to the processes of health and disease, is expressed through emotions that nursing students have to deal with in the course of care and their formative experiences in clinical teaching. Students have learning needs not only to manage emotions in the context of customer care, but also in terms of their own internal world, emotional conflicts, emotional stress and burn-out. With the present literature review, we intend to explore existing evidence regarding the ways in which the nurse supervisor's support towards nursing students potentiates the development of their competences for the performance of emotional labour. These skills prove to be the key in the ability to manage the emotionally intense situations of care practice and the support function of the nursing supervisor contributes to the development of such competences.