Ecocardiografia em «Cor Triatriatum Dexter»

"Cor triatriatum dexter" (CTD) is an unusual cyanotic cardiac defect in which the right atrium is subdivided into two distinct chambers due to the persistence of the "sinus venosus" valve. Two patients with CTD ho were evaluated and treatment in 1979 and 1992 are described: the first one, had total anomalous pulmonary venous return to the coronary sinus or "cor triatriatum sinister" as preoperative diagnosis based on M-mode echocardiographic findings. The presence of a membrane inside the right atrium was suspected on cineangiogram. The other one had a preoperative diagnosis of CTD. Anatomic relationships and physiological effects were established by two dimensional and Doppler ultrasonography and confirmed at cardiac catheterization and surgery. High resolution two dimensional echocardiography coupled with Doppler ultrasonography has a definite role in the study of this heart defect.

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.

Monitoring Abacavir Bioactivation in Humans: Screening for an Aldehyde Metabolite

The anti-HIV drug abacavir is associated with idiosyncratic hypersensitivity reactions and cardiotoxicity. Although the mechanism underlying abacavir-toxicity is not fully understood, drug bioactivation to reactive metabolites may be involved. This work was aimed at identifying abacavir-protein adducts in the hemoglobin of HIV patients as biomarkers of abacavir bioactivation and protein modification. The protocol received prior approval from the Hospital Ethics Committee, patients gave their written informed consent and adherence was controlled through a questionnaire. Abacavir-derived Edman adducts with the N-terminal valine of hemoglobin were analyzed by an established liquid chromatography-electrospray ionization-tandem mass spectrometry method. Abacavir-valine adducts were detected in three out of ten patients. This work represents the first evidence of abacavir-protein adduct formation in humans. The data confirm the ability of abacavir to modify self-proteins and suggest that the molecular mechanism(s) of some abacavir-induced adverse reactions may require bioactivation.

Transthyretin Amyloidosis: Chaperone Concentration Changes and Increased Proteolysis in the Pathway to Disease

Transthyretin amyloidosis is a conformational pathology characterized by the extracellular formation of amyloid deposits and the progressive impairment of the peripheral nervous system. Point mutations in this tetrameric plasma protein decrease its stability and are linked to disease onset and progression. Since non-mutated transthyretin also forms amyloid in systemic senile amyloidosis and some mutation bearers are asymptomatic throughout their lives, non-genetic factors must also be involved in transthyretin amyloidosis. We discovered, using a differential proteomics approach, that extracellular chaperones such as fibrinogen, clusterin, haptoglobin, alpha-1-anti-trypsin and 2-macroglobulin are overrepresented in transthyretin amyloidosis. Our data shows that a complex network of extracellular chaperones are over represented in human plasma and we speculate that they act synergistically to cope with amyloid prone proteins. Proteostasis may thus be as important as point mutations in transthyretin amyloidosis.

Caracterização da Utilização de Sugamadex no Centro Hospitalar de Lisboa Central - Hospital de S. José

Introdução O sugamadex é uma gama ciclodextrina modificada que forma um complexo com os bloqueadores neuromusculares rocurónio e vecurónio, revertendo o bloqueio neuromuscular (BNM) induzido por estes fármacos1,2,3,4. O sugamadex apresentou valor terapêutico acrescentado em relação aos anticolinesterásicos, nomeadamente à neostigmina, para a reversão do BNM causado pelo rocurónio e vecurónio1,3. No Hospital de São José (HSJ) este medicamento foi introduzido em Outubro de 2010 para a reversão do BNM profundo e nas situações de risco de vida imediato associadas a via aérea difícil com impossibilidade de ventilar e de entubar. A dispensa do sugamadex é efectuada por reposição de stock mediante envio de justificação clínica aos Serviços Farmacêuticos (SF). Objetivo Caracterizar a utilização de sugamadex no HSJ: evolução do consumo, serviços clínicos utilizadores e adequação da utilização clínica face às indicações aprovadas pela Comissão de Farmácia e Terapêutica (CFT). Métodos Pesquisa e análise bibliográfica. Recolha, através da do sistema de gestão integrada do circuito do medicamento, dos dados de consumo desde Outubro de 2010 até Junho de 2015, por semestre e por serviço clínico. Recolha das indicações terapêuticas em que o sugamadex foi administrado, no período acima referido, através da consulta das justificações clínicas. Análise retrospectiva dos dados recolhidos. Resultados Apresentação gráfica dos consumos de sugamadex nos serviços utilizadores no período em estudo. Apresentação gráfica das indicações terapêuticas em que foi administrado, por serviço e no período em estudo. Conclusões O consumo de sugamadex tem um evidente crescimento desde o seu início de utilização. A justificação dominante para a utilização do sugamadex é a curarização residual. Verifica-se um alargamento do âmbito de utilização, face às indicações aprovadas pela CFT. Decorridos cinco anos de utilização, justifica-se uma reavaliação das indicações de utilização no HSJ pela CFT. Bibliografia 1. Chambers D, Paulden M, Paton F, Heirs M, Duffy S, Craig D, et al. Sugammadex for the reversal of muscle relaxation in general anaesthesia: a systematic review and economic assessment. Health Technol Assess 2010;14(39). 2. De Boer HD, Van Egmond J, Driessen JJ, Booij LH. Update on the management of neuromuscular block: Focus on sugammadex. Neuropsychiatr Dis Treat 2007;3:539-44. 3. Relatório avaliação prévia de medicamento para uso humano em meio hospitalar – DCI – Sugamadex (06-05-2010) – Infarmed - acedido a 27/08/2015 www.infarmed.pt. 4. Resumo das Características do Medicamento Bridion® 100 mg/ml solução injectável - acedido a 27/08/2015 www.ema.europa.eu/.