Pharmacogenomics, CYP2D6, and tamoxifen: A survey of the reasons sustaining european clinical practice paradigms

Tamoxifen is a drug that is often used in the clinical management of breast cancer. CYP2D6 is a key metabolizing enzyme that is involved in the conversion of tamoxifen to its active drug metabolites. CYP2D6 has several alleles that metabolize tamoxifen and other drugs at different rates that can alter therapeutic impact, a characteristic that renders it one of the most studied enzymes in the field of pharmacogenetics. Background and objectives: Portugal has no implemented measures based on pharmacogenomics analysis prior to therapy that might function as a cultural sample control when analyzing the individual and economic factors present in clinical practice paradigms. Therefore, we aim to investigate the impact of CYP2D6 genotyping of the tamoxifen metabolizing enzymes in the clinical management of breast cancer patients. Materials and Methods: Qualitative/quantitative studies regarding the impact of pharmacogenomics in breast cancer; personal interviews in different Portuguese laboratories within hospital setting using a survey. Analysis of data through interviews to management board and/or decision makers from major oncological centers. Results: Reasons for common adoption of pharmacogenomics practice are contradictory and based both in economic factors and cultural/clinical bias. Conclusions: This research study identifies specific cultural and/or clinical bias that act as obstacles to pharmacogenomic implementation and proposes viable courses of action that might bring about change in cultural/medical habits.This research was partially support by UID/BIM/04293/2013 and UID/EQU/0470/2019

Changes in the biophysical properties of the cell membrane are involved in the response of neurospora crassa to staurosporine

Neurospora crassa is a non-pathogenic filamentous fungus widely used as a multicellular eukaryotic model. Recently, the biophysical properties of the plasma membrane of N. crassa conidia were thoroughly characterized. They evolve during conidial germination at a speed that depends on culture conditions, suggesting an important association between membrane remodeling and the intense membrane biogenesis that takes place during the germinative process. Staurosporine (STS) is a drug used to induce programmed cell death in various organisms. In N. crassa, STS up-regulates the expression of the ABC transporter ABC-3, which localizes at the plasma membrane and pumps STS out. To understand the role of plasma membrane biophysical properties in the fungal drug response, N. crassa was subjected to STS treatment during early and late conidial development stages. Following 1 h treatment with STS, there is an increase in the abundance of the more ordered, sphingolipid-enriched, domains in the plasmamembrane of conidia. This leads to higher fluidity in othermembrane regions. The global order of the membrane remains thus practically unchanged. Significant changes in sphingolipid-enriched domains were also observed after 15min challenge with STS, but they were essentially opposite to those verified for the 1 h treatment, suggesting different types of drug responses. STS effects on membrane properties that are more dependent on ergosterol levels also depend on the developmental stage. There were no alterations on 2 h-grown cells, clearly contrasting to what happens at longer growth times. In this case, the differences were more marked for longer STS treatment, and rationalized considering that the drug prevents the increase in the ergosterol/glycerophospholipid ratio that normally takes place at the late conidial stage/transition to the mycelial stage. This could be perceived as a drug-induced development arrest after 5 h growth, involving ergosterol, and pointing to a role of lipid rafts possibly related with an up-regulated expression of the ABC-3 transporter. Overall, our results suggest the involvement of membrane ordered domains in the response mechanisms to STS in N. crassa. Neurospora crassa is a non-pathogenic filamentous fungus widely used as a multicellular eukaryotic model. Recently, the biophysical properties of the plasma membrane of N. crassa conidia were thoroughly characterized. They evolve during conidial germination at a speed that depends on culture conditions, suggesting an important association between membrane remodeling and the intense membrane biogenesis that takes place during the germinative process. Staurosporine (STS) is a drug used to induce programmed cell death in various organisms. In N. crassa, STS up-regulates the expression of the ABC transporter ABC-3, which localizes at the plasma membrane and pumps STS out. To understand the role of plasma membrane biophysical properties in the fungal drug response, N. crassa was subjected to STS treatment during early and late conidial development stages. Following 1 h treatment with STS, there is an increase in the abundance of the more ordered, sphingolipid-enriched, domains in the plasmamembrane of conidia. This leads to higher fluidity in othermembrane regions. The global order of the membrane remains thus practically unchanged. Significant changes in sphingolipid-enriched domains were also observed after 15min challenge with STS, but they were essentially opposite to those verified for the 1 h treatment, suggesting different types of drug responses. STS effects on membrane properties that are more dependent on ergosterol levels also depend on the developmental stage. There were no alterations on 2 h-grown cells, clearly contrasting to what happens at longer growth times. In this case, the differences were more marked for longer STS treatment, and rationalized considering that the drug prevents the increase in the ergosterol/glycerophospholipid ratio that normally takes place at the late conidial stage/transition to the mycelial stage. This could be perceived as a drug-induced development arrest after 5 h growth, involving ergosterol, and pointing to a role of lipid rafts possibly related with an up-regulated expression of the ABC-3 transporter. Overall, our results suggest the involvement of membrane ordered domains in the response mechanisms to STS in N. crassa.Fundação para a Ciência e a Tecnologia (FCT), Portugal, is acknowledged for grants PTDC/BBB-BQB/6071/2014, UID/Multi/00612/2013, IF/00317/2012, and PT2020 referring to research unit 4293. FS acknowledges Ph.D. scholarship SFRH/BD/108031/2015, also from FCT

Sea level changes along the Indian coast: Observations and projections

Sea level changes can be of two types: (i) changes in the mean sea level and (ii) changes in the extreme sea level. The former is a global phenomenon while the latter is a regional phenomenon. Estimates of mean sea level rise made from past tide gauge data at selected stations along the coast of India indicate a rise of slightly less than 1 mm/year; however these estimates need to be corrected by including the rates of vertical land movements, whose measurements are not available at present. Simulation results of a regional climate model, HadRM2, were analysed for the northern Indian Ocean to provide the future scenarios of the occurrence of tropical cyclones in the Bay of Bengal for the period 2041-60. This model simulations consist of a control run with concentration of CO2 kept constant at 1990 levels and a perturbed run with transient increase in the concentrations of CO2 (GHG) according to the IS92a scenario for the period 2041-2060. The simulation results show increase in frequencies of tropical cyclones in the Bay, particularly intense events during the postmonsoon period, for the increased GHG run. A storm surge model was used to compute the surges associated with the cyclones generated by the climate model. The storm surge model was forced by the wind field from HadRM2 over the model domain and tides prescribed along the open boundary from a global tidal model. The frequency of high surges is found to be higher in the model run forced by winds from increased GHG run than in the model run forced by winds from the control run

Sickle Cell Disease and Cerebrovascular Stroke: A Preventable Event

Introdução: Na criança, a etiologia do acidente vascular cerebral (AVC) é conhecida em 75% dos casos, sendo a anemia de células falciformes (ACF) a mais frequente na criança de raça negra. O interesse deste caso clínico reside na forma de apresentação pouco habitual e curso evitável. Caso clínico: Criança de raça negra com 27 meses de idade, sem antecedentes relevantes, admitida por sinais neurológicos focais de instalação súbita. A tomografia computorizada cranio-encefálica e ressonância magnética evidenciaram lesão isquémica aguda extensa e alterações compatíveis com AVC silencioso prévio. Analiticamente apresentava anemia normocítica, muitos drepanocitos de formação espontânea e 87% de hemoglobina S. Neste contexto, foi submetida a transfusão-permuta. Conclusão: O AVC como complicação da ACF pode acontecer em idades precoces e surgir como quadro inaugural. Pensamos que se justifica divulgar o rastreio pré-natal e realizar um estudo da relação custo-benefício para a implementação de um rastreio neonatal desta patologia em Portugal

Injury to the Superior Gluteal Artery during Intramedullary Fixation of a Proximal Femoral Fracture - A Case Report

Proximal femoral fractures represent a health problem of global proportions. Iatrogenic vascular lesion in the treatment of these fractures is an unusual potentially lethal complication, reported in only 0.2% of trochanteric fractures treated with intramedullary implants. Superior gluteal artery injury is extremely rare, with only two cases reported in literature.info:eu-repo/semantics/publishedVersio

Fluorometric Liposome Screen for Inhibitors of a Physiologically Important Bacterial Ion Channel

The bacterial K+ homeostasis machinery is widely conserved across bacterial species, and different from that in animals. Dysfunction in components of the machinery has an impact on intracellular turgor, membrane potential, adaptation to changes in both extracellular pH and osmolarity, and in virulence. Using a fluorescence-based liposome flux assay, we have performed a high-throughput screen to identify novel inhibitors of the KtrAB ion channel complex from Bacillus subtilis, a component of the K+ homeostasis machinery that is also present in many bacterial pathogens. The screen identified 41 compounds that inhibited K+ flux and that clustered into eight chemical groups. Many of the identified inhibitors were found to target KtrAB with an in vitro potency in the low µM range. We investigated the mechanisms of inhibition and found that most molecules affected either the membrane component of the channel, KtrB alone or the full KtrAB complex without a preference for the functional conformation of the channel, thus broadening their inhibitory action. A urea derivative molecule that inhibited the membrane component of KtrAB affected cell viability in conditions in which KtrAB activity is essential. With this proof-of-concept study, we demonstrate that targeting components of the K+ homeostasis machinery has the potential as a new antibacterial strategy and that the fluorescence-based flux assay is a robust tool for screening chemical libraries.This work was supported by FEDER funds through COMPETE 2020-POCI, Portugal 2020, and FCT – Fundação para a Ciência e a Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior: POCI-01-0145-FEDER-029863 (PTDC/BIA-BQM/29863/2017), and by “Fundação Luso-Americana para o Desenvolvimento” FLAD Life Science 2020 awarded to JM-C. We acknowledge FCT fellowship SFRH/BPD/105672/2015 and contract DL 57/2016/CP1355/CT0026 awarded to AF, fellowship SFRH/BPD/107785/2015 to AP, and fellowship SFRH/BD/123761/2016 to CT-D

Modelling and analysis of time dependent processes in a chemically reactive mixture

In this paper, we study the propagation of sound waves and the dynamics of local wave disturbances induced by spontaneous internal fluctuations in a reactive mixture. We consider a non-diffusive, non-heat conducting and non-viscous mixture described by an Eulerian set of evolution equations. The model is derived from the kinetic theory in a hydrodynamic regime of a fast chemical reaction. The reactive source terms are explicitly computed from the kinetic theory and are built in themodel in a proper way. For both time-dependent problems, we first derive the appropriate dispersion relation, which retains the main effects of the chemical process, and then investigate the influence of the chemical reaction on the properties of interest in the problems studied here. We complete our study by developing a rather detailed analysis using the Hydrogen–Chlorine system as reference. Several numerical computations are included illustrating the behavior of the phase velocity and attenuation coefficient in a low-frequency regime and describing the spectrum of the eigenmodes in the small wavenumber limit.The paper is partially supported by the Research Centre of Mathematics of the University of Minho, with the Portuguese Funds from the Foundation for Science and Technology (FCT) through the Project UID/MAT/00013/2013. We wish to thank the anonymous Referees for their valuable comments and suggestions that helped us to improve the paper.info:eu-repo/semantics/publishedVersio

Skin Disease in Liver and Kidney Transplant Recipients Referred to the Department of Dermatology and Venereology

Introdução: Foram descritas várias doenças cutâneas em doentes transplantados, em relação com a terapêutica imunossupressora instituída. Pretendemos caracterizar o espectro clínico das patologias dermatológicas e comparar os diagnósticos entre os doentes transplantados hepáticos e os doentes transplantados renais. Material e Métodos: Estudo descritivo e retrospectivo através da consulta de processos clínicos de todos os doentes submetidos a transplante hepático ou renal entre 2000 - 2010 referenciados à Consulta de Dermatologia e Venereologia. Resultados: Observámos 319 doentes transplantados (23,5%) e apurámos 410 diagnósticos (230 na sub-população com transplante hepático e 180 na sub-população com transplante renal), divididos em quatro grupos: 1) infecções cutâneas; 2) cancro cutâneo ou lesões precursoras; 3) manifestações cutâneas relacionadas com efeitos secundários de fármacos; 4) outras patologias dermatológicas não iatrogénicas. As infecções cutâneas foram as mais observadas (42,2%), em média 32,7 meses após o transplante. Este grupo incluiu 20,5% de infecções fúngicas, 12,7% virais e 8,5% bacterianas. Identificámos patologia tumoral e lesões precursoras em 11,7% dos casos, em média 44,8 meses após o transplante e assumindo maior importância na sub-população com transplante renal (20,6% vs 4,8% nos transplantados hepáticos; P < 0,001). Os transplantados renais apresentaram predomínio de carcinomas espinocelulares (CEC) sobre os casos de carcinomas basocelulares (CBC), numa razão CEC:CBC de 1,3:1 mas nos transplantados hepáticos verificou-se uma razão CBC: carcinomas de 3,5:1. Ocorreram efeitos secundários de fármacos em 10,5% dos casos e outras patologias dermatológicas não iatrogénicas em 35,6%. Discussão: Apesar da patologia tumoral ser a mais referida na literatura, as infecções cutâneas foram as mais observadas na nossa amostra. As diferenças significativas entre as duas sub-populações estudadas podem estar relacionadas com o maior grau de imunossupressão a que os doentes transplantados renais estão sujeitos. Conclusão: Dada a elevada frequência de patologia cutânea nestes doentes é essencial incluir o acesso a consultas de Dermatologia e Venereologia nos cuidados multi-disciplinares pós-transplante

Major CD4 T-Cell Depletion and Immune Senescence in a Patient with Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) results from primary defects in phagocytic reactive oxygen species (ROS) production. T-cell evaluation is usually neglected during patients’ follow-up, although T-cell depletion has been reported in CGD through unknown mechanisms. We describe here a 36-year-old patient with X-linked CGD with severe CD4 T-cell depletion <200 CD4 T-cells/μl, providing insights into the mechanisms that underlie T-cell loss in the context of oxidative burst defects. In addition to the typical infections, the patient featured a progressive T-cell loss associated with persistent lymphocyte activation, expansion of interleukin (IL)-17-producing CD4 T-cells, and impaired thymic activity, leading to a reduced replenishment of the T-cell pool. A relative CD4 depletion was also found at the gut mucosal level, although no bias to IL-17-production was documented. This immunological pattern of exhaustion of immune resources favors prompt, potentially curative, therapeutic interventions in CGD patients, namely, stem-cell transplantation or gene therapy. Moreover, this clinical case raises new research questions on the interplay of ROS production and T-cell homeostasis and immune senescence