Brain natriuretic peptide is a long-term cardiovascular predictor in carotid endarterectomy.

BACKGROUND: In noncardiac surgery, several biomarkers are known to play a role in predicting long-term complications, such as major adverse cardiovascular events (MACE), myocardial infarction, or death. Carotid endarterectomy (CEA) is considered a low to medium-risk surgery for carotid stenosis aimed at preventing stroke events. Brain natriuretic peptide (BNP) is a biomarker with potential prognostic value regarding MACE. Since its role in patients undergoing CEA is unknown, this study aims to assess the potential role of BNP as a short and long-term predictor of all-cause mortality and MACE in patients undergoing CEA. METHODS: From a prospective database, patients who underwent CEA under regional anesthesia (RA) at a tertiary hospital center were enrolled, and a post hoc analysis was conducted. Patients on which BNP levels were measured up to fifteen days before surgery, and two groups based on the BNP threshold (200 pg/mL) were defined and compared. Kaplan Meier survival curves and adjusted hazard ratios (aHR) were assessed by multivariable Cox regression. The primary outcome was the incidence of long-term MACE and all-cause mortality. Secondary outcomes included the incidence of AMI and AHF. RESULTS: A total of 89 patients were evaluated. The mean age of the cohort was 71.2 ± 8.7 years, with 71 (79.8%) males, and presented a median follow-up of 30 [13.5-46.4] months. BNP > 200 pg/mL has demonstrated positive predictive value for MACE (aHR: 5.569, confidence interval (CI): 2.441-12.7, p < 0.001) and all-cause mortality (aHR: 3.469, CI: 1.315-9.150, p = 0.018). CONCLUSION: BNP has been demonstrated to independently predict long-term all-cause mortality, MACE and AMI following CEA. It serves as a low-cost, ready-to-use biomarker, although further studies are necessary.

Offshore produced water treatment by a biofilm reactor on the seabed: The effect of temperature and matrix characteristics.

In many industrial processes a large amount of water with high salinity is co-produced whose treatment poses considerable challenges to the available technologies. The produced water (PW) from offshore operations is currently being discharged to sea without treatment for dissolved pollutants due to space limitations. A biofilter on the seabed adjacent to a production platform would negate all size restrictions, thus reducing the environmental impact of oil and gas production offshore. The moving bed biofilm reactor (MBBR) was investigated for PW treatment from different oilfields in the North Sea at 10 °C and 40 °C, corresponding to the sea and PW temperature, respectively. The six PW samples in study were characterized by high salinity and chemical oxygen demand with ecotoxic effects on marine algae S. pseudocostatum (0.4%

ECMO for drug-refractory electrical storm without a reversible trigger: a retrospective multicentric observational study.

AIMS: Drug-refractory electrical storm (ES) is a life-threatening medical emergency. We describe the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in drug-refractory ES without a reversible trigger, for which specific guideline recommendations are still lacking. METHODS AND RESULTS: Retrospective observational study in four Iberian centres on the indications, treatment, complications, and outcome of drug-refractory ES not associated with acute coronary syndromes, decompensated heart failure, drug toxicity, electrolyte disturbances, endocrine emergencies, concomitant acute illness with fever, or poor compliance with anti-arrhythmic drugs, requiring VA-ECMO for circulatory support. Thirty-four (6%) out of 552 patients with VA-ECMO for cardiogenic shock were included [71% men; 57 (44-62) years], 65% underwent cardiopulmonary resuscitation before VA-ECMO implantation, and 26% during cannulation. Left ventricular unloading during VA-ECMO was used in 8 (24%) patients: 3 (9%) with intraaortic balloon pump, 3 (9%) with LV vent, and 2 (6%) with Impella. Thirty (88%) had structural heart disease and 8 (24%) had an implantable cardioverter-defibrillator. The drug-refractory ES was mostly due to monomorphic ventricular tachycardia (VT) and ventricular fibrillation (VF) (59%), isolated monomorphic VT (26%), polymorphic VT (9%), or VF (6%). Thirty-one (91%) required deep sedation, 44% overdrive pacing, 36% catheter ablation, and 26% acute autonomic modulation. The main complications were nosocomial infection (47%), bleeding (24%), and limb ischaemia (21%). Eighteen (53%) were weaned from VA-ECMO, and 29% had heart transplantation. Twenty-seven (79%) survived to hospital discharge (48 (33-82) days). Non-survivors were older [62 (58-67) vs. 54 (43-58); P < 0.01] and had a higher first rhythm disorder-to-ECMO interval [0 (0-2) vs. 2 (1-11) days; P = 0.02]. Seven (20%) had rehospitalization during follow-up [29 (12-48) months], with ES recurrence in 6%. CONCLUSIONS: VA-ECMO bridged drug-refractory ES without a reversible trigger with a high success rate. This required prolonged hospital stays and coordination between the ECMO centre, the electrophysiology laboratory, and the heart transplant programme.

The impact of comorbid psychiatric disorders on chronic obstructive pulmonary disease (COPD) hospitalizations: a nationwide retrospective study.

AIMS: To characterize the register of a secondary diagnosis of mental illnesses in all chronic obstructive pulmonary disease (COPD) hospitalizations registered in Portugal from 2008 to 2015 and explore their impact on hospitalization outcomes. METHODS: A retrospective observational study was conducted. Hospitalizations of patients with at least 40 years old, discharged between 2008 and 2015 with a primary diagnosis of COPD (ICD-9-CM codes 491.x, 492.x and 496) were retrieved from a national administrative database. Comorbid psychiatric diagnoses were identified and defined by the HCUP Clinical Classification Software (CCS) category codes 650-670 (excluding 662). Length of hospital stay (LoS), admission type, in-hospital mortality, and estimated hospital charges were analyzed according to psychiatric diagnostic categories using sex and age-adjusted models. RESULTS: Of 66,661 COPD hospitalizations, 25,869 (38.8%) were episodes with a registered psychiatric comorbidity. These were more likely to correspond to younger inpatients (OR = 2.16, 95%CI 2.09-2.23; p < 0.001), to stay longer at the hospital (aOR = 1.08, 95%CI 1.05-1.12; p < 0.001), to incur in higher estimated hospital charges (aOR = 1.37, 95%CI 1.33-1.42; p < 0.001) and to be urgently admitted (aOR = 1.33, 95%CI 1.23-1.44; p < 0.001). After adjustment for age, in-hospital mortality was lower for episodes with psychiatric diagnoses (aOR = 0.90; 95%CI 0.84-0.96; p < 0.001), except for organic and neurodegenerative diseases category and developmental disorders, intellectual disabilities and disorders usually diagnosed in infancy, childhood, or adolescence category. DISCUSSION: These findings corroborate the additional burden placed by psychiatric disorders on COPD hospitalizations, highlighting the importance of individualizing care to address these comorbidities and minimize their impact on treatment outcomes.

Influenza A virus propagation requires the activation of the unfolded protein response and the accumulation of insoluble protein aggregates.

Influenza A virus (IAV) employs multiple strategies to manipulate cellular mechanisms and support proper virion formation and propagation. In this study, we performed a detailed analysis of the interplay between IAV and the host cells' proteostasis throughout the entire infectious cycle. We reveal that IAV infection activates the inositol requiring enzyme 1 (IRE1) branch of the unfolded protein response, and that this activation is important for an efficient infection. We further observed the accumulation of virus-induced insoluble protein aggregates, containing both viral and host proteins, associated with a dysregulation of the host cell RNA metabolism. Our data indicate that this accumulation is important for IAV propagation and favors the final steps of the infection cycle, more specifically the virion assembly. These findings reveal additional mechanisms by which IAV disrupts host proteostasis and uncovers new cellular targets that can be explored for the development of host-directed antiviral strategies.

Use and uptake of technology by people with dementia and their supporters during the COVID-19 pandemic.

OBJECTIVE: This rapid review aims to identify the types of technologies used by people with dementia and their supporters during the COVID-19 pandemic, and the issues which influenced technology adoption within their usual care routines. METHODS: PubMed, PsychInfo, Scopus, and Cochrane COVID reviews were searched to identify peer-review studies published since 2020. A total of 18 studies were included and synthesised thematically. RESULTS: Of these, most were conducted in the community (n = 15) with people with dementia only (n = 11) and involved qualitative methods (n = 11). The majority (n = 12) focused on digital off-the-shelf and low-cost solutions, such as free video conferencing platforms, to access care, socialise or take part in interventions. Whilst often well-accepted and associated with positive outcomes (such as improved social connectedness), lack of digital literacy or support to use technologies, limited access to appropriate technology, individuals' physical, cognitive, or sensory difficulties, were highlighted and likely to threaten the adoption of these solutions. The quality of the evidence was mixed, neither very robust nor easily generalisable which may be attributed to the challenges of conducting research during the pandemic or the need to rapidly adapt to a new reality. CONCLUSION: While COVID-19 has fast-tracked the adoption of technology, its use is likely to continue beyond the pandemic. We need to ensure this technology can leverage dementia support and care and that people with dementia are enabled and empowered to use it.

Os efeitos da pandemia no bem-estar dos enfermeiros brasileiros no combate ao Covid-19: uma revisão de escopo / The effects of the pandemic on the well-being of brazilian nurses in the fight against Covid-19: a scoping review / Los efectos de la pandemia en el bienestar de las enfermeras brasileñas en la lucha contra el Covid-19: a scoping review

Introdução: Estudos indicam que os profissionais de saúde têm alto risco de desenvolver sintomas relacionados à saúde mental, especialmente depressão, ansiedade e estresse. Objetivo: identificar e sintetizar os estudos sobre os preditores relacionados a saúde mental entre enfermeiros que atuam na linha de frente no combate ao COVID- 19. Método: Trata-se de uma revisão de escopo, sem limitação de linguagem e ano, nas bases BVS, PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, CAPES e ProQuest. Foi realizada síntese narrativa. Resultados: A pandemia da COVID-19 trouxe sérios impactos a saúde mental dos profissionais de enfermagem, os achados revelaram cinco temas principais sentimento de insegurança, falta de equipamentos de proteção individual, falta de exames diagnósticos, mudanças no fluxo de atendimento e medo do desconhecido. Existe uma associação significativa entre o bem-estar físico e metal e a produtividade laboral. Conclusão: Destaca-se os desafios enfrentados pelos enfermeiros no combate da COVID-19, mesmo com a repercussões no ambiente de trabalho os enfermeiros ainda padecem de reconhecimento adequado que incluem situações de estresse, ansiedade, depressão e estão diretamente relacionadas à frustração, esgotamento físico e mental, sentimento de impotência e insegurança profissional vivenciados durante a pandemia, principalmente por jovens profissionais sem experiência no cuidado de pacientes críticos.

Introduction: Studies indicate that health professionals are at high risk of developing symptoms related to mental health, especially depression, anxiety and stress. Objective: identify and synthesize studies on mental health-related predictors among nurses who work on the front line in the fight against COVID-19. Method: This is a scope review, without language and year limitations, in the VHL, PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, CAPES and ProQuest databases. Narrative synthesis was performed. Results: The COVID-19 pandemic had serious impacts on the mental health of nursing professionals, the findings revealed five main themes: feeling of insecurity, lack of personal protective equipment, lack of diagnostic tests, changes in the flow of care and fear of the unknown. There is a significant association between physical and mental well-being and labor productivity. Conclusion: The challenges faced by nurses in the fight against COVID-19 are highlighted, even with the repercussions in the work environment, nurses still suffer from adequate recognition and include situations of stress, anxiety and even depression, which are directly related to frustration , physical and mental exhaustion, feeling of helplessness and professional insecurity experienced during the pandemic, especially by young professionals with no experience in caring for critically ill patients.

Introducción: Los estudios indican que los profesionales de la salud tienen un alto riesgo de desarrollar síntomas relacionados con la salud mental, especialmente depresión, ansiedad y estrés. Objetivo: identificar y sintetizar estudios sobre predictores relacionados a la salud mental entre enfermeros que trabajan en primera línea en la lucha contra el COVID-19. Método: Se trata de una revisión de alcance, sin limitaciones de idioma y año, en las bases de datos BVS, PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, CAPES y ProQuest. Se realizó una síntesis narrativa. Resultados: La pandemia de COVID-19 tuvo graves impactos en la salud mental de los profesionales de enfermería, los hallazgos revelaron cinco temas principales: sensación de inseguridad, falta de equipo de protección personal, falta de pruebas diagnósticas, cambios en el flujo de atención y miedo a lo desconocido. Existe una asociación significativa entre el bienestar físico y mental y la productividad laboral. Conclusiones: Se destacan los retos a los que se enfrentan las enfermeras en la lucha contra la COVID-19, aún con las repercusiones en el ámbito laboral, las enfermeras siguen sufriendo un reconocimiento adecuado e incluyen situaciones de estrés, ansiedad e incluso depresión, que están directamente relacionadas con la frustración , el agotamiento físico y mental, la sensación de impotencia y la inseguridad profesional experimentada durante la pandemia, especialmente por profesionales jóvenes sin experiencia en el cuidado de pacientes críticos.

Epilepsy hospitalizations and mental disorders: A Portuguese population-based observational retrospective study (2008-2015).

BACKGROUND: Psychiatric comorbidities are highly frequent in people with epilepsy and were found to be markers of poorer prognosis. These comorbidities increase the use of healthcare resources, including emergency department visits and inpatient care. Despite this, there is little information on healthcare utilization associated with a wide range of comorbid mental disorders in people with epilepsy (PWE). OBJECTIVE: To characterize registered mental disorders among all hospitalizations with a primary diagnosis of epilepsy and to analyze their association with crucial hospitalization outcomes. METHODS: An observational retrospective study was performed using administrative data from hospitalization episodes with epilepsy as the primary diagnosis discharged between 2008 and 2015. Mental disorder categories 650 to 670 from Clinical Classification Software were selected as secondary diagnoses. Mann-Whitney U, Kruskall-Wallis, and Chi-squared tests were used to establish comparisons. For each episode, data regarding hospitalization outcomes was retrieved, including length of stay (LoS), in-hospital mortality (IHM), 8-year period readmissions, and total estimated charges. RESULTS: Overall, 27,785 hospitalizations were analyzed and 33.9% had registered mental disorders, with alcohol-related disorders being the most prevalent (11.7%). For episodes with a concomitant register of a mental disorder, LoS was significantly longer (5.0 vs. 4.0 days, P <0.001), and IHM was higher (2.8% vs. 2.2%, P <0.001), as were readmissions (25.5% vs. 23.7%, P <0.001), and median episodes' charges (1,578.7 vs. 1,324.4 euros, P <0.001). CONCLUSION: Epilepsy-related hospitalizations with registered mental disorders heightened the utilization of healthcare resources, stressing the importance of diagnosing and treating mental disorders in PWE.

Standardized approach for extubation during extracorporeal membrane oxygenation in severe acute respiratory distress syndrome: a prospective observational study.

BACKGROUND: Extubation during extracorporeal oxygenation (ECMO) in severe acute respiratory distress syndrome (ARDS) has not been well studied. Despite the potential benefits of this strategy, weaning from ECMO before liberation from invasive mechanical ventilation remains the most frequent approach. Our aim was to evaluate the safety and feasibility of a standardized approach for extubation during ECMO in patients with severe ARDS. RESULTS: We conducted a prospective observational study to assess the safety and feasibility of a standardized approach for extubation during ECMO in severe ARDS among 254 adult patients across 4 intensive care units (ICU) from 2 tertiary ECMO centers over 6 years. This consisted of a daily assessment of clinical and gas exchange criteria based on an Extracorporeal Life Support Organization guideline, with extubation during ECMO after validation by a dedicated intensive care medicine specialist. Fifty-four (21%) patients were extubated during ECMO, 167 (66%) did not reach the clinical criteria, and in 33 (13%) patients, gas exchange precluded extubation during ECMO. At ECMO initiation, there were fewer extrapulmonary organ dysfunctions (lower SOFA score [OR, 0.88; 95% CI, 0.79-0.98; P = .02] with similar PaO2/FiO2) when compared with patients not extubated during ECMO. Extubation during ECMO associated with shorter duration of invasive mechanical ventilation (7 (4-18) vs. 32 (18-54) days; P < .01) and of ECMO (12 (7-25) vs. 19 (10-41) days; P = .01). This was accompanied by a lower incidence of hemorrhagic shock (2 vs. 11%; P = .05), but more cannula-associated deep vein thrombosis (49 vs. 31%; P = .02) and failed extubation (20 vs. 6%; P < .01). There were no increased major adverse events. Extubation during ECMO is associated with a lower risk of all-cause death, independently of measured confounding (adjusted logistic regression OR 0.23; 95% confidence interval 0.08-0.69, P = .008). CONCLUSIONS: A standardized approach was safe and feasible allowing extubation during ECMO in 21% of patients with severe ARDS, selecting patients who will have a shorter duration of invasive mechanical ventilation, ECMO course, and ICU stay, as well as fewer infectious complications, and high hospital survival.

Combined superior mesenteric artery syndrome and nutcraker syndrome presenting as acute pancreatitis: a case report.

Superior mesenteric artery syndrome designates compression of the third part of the duodenum between the superior mesenteric artery and the aorta. This condition has a low incidence, being more common in thin young women. Nutcracker syndrome is compression of the left renal vein between the superior mesenteric artery and the aorta. Both entities are rare, and their coexistence has been reported in a few cases. Conservative treatment targeting weight gain is sufficient in most cases. An association between the superior mesenteric artery syndrome and acute pancreatitis has rarely been reported. We intend to describe the case of an 18-year-old girl who was admitted to the emergency room with epigastric pain and emesis. Our investigation revealed acute acalculous pancreatitis. During work-up, we discovered superior mesenteric artery syndrome and a compressed left renal vein. The patient is on conservative treatment, and her symptoms have improved.

A síndrome da artéria mesentérica superior designa compressão da terceira parte do duodeno pela artéria mesentérica superior e a aorta. Essa condição tem uma baixa incidência, sendo mais comum em mulheres jovens magras. A síndrome de quebra-nozes resulta da compressão da veia renal esquerda pela artéria mesentérica superior e a aorta. Ambas as entidades são raras, e a sua coexistência foi descrita em poucos casos. Tratamento conservador com o objetivo de ganho ponderal é suficiente na maioria dos casos. A associação entre a síndrome da artéria mesentérica superior e a pancreatite aguda foi raramente relatada. Pretendemos descrever o caso de uma jovem de 18 anos que recorreu ao serviço de urgência com epigastralgia e vômitos. A investigação realizada revelou pancreatite aguda alitiásica. Durante o estudo complementar, foi identificada a síndrome da artéria mesentérica superior, bem como uma veia renal esquerda comprimida. A paciente encontra-se em tratamento conservador, apresentando melhora clínica.

Whey-based diet containing medium chain triglycerides modulates the gut microbiota and protects the intestinal mucosa from chemotherapy while maintaining therapy efficacy.

Cytotoxicity (i.e. cell death) is the core mechanism by which chemotherapy induces its anti-cancer effects. Unfortunately, this same mechanism underpins the collateral damage it causes to healthy tissues. The gastrointestinal tract is highly susceptible to chemotherapy's cytotoxicity, resulting in ulcerative lesions (termed gastrointestinal mucositis, GI-M) that impair the functional capacity of the gut leading to diarrhea, anorexia, malnutrition and weight loss, which negatively impact physical/psychological wellbeing and treatment adherence. Preventing these side effects has proven challenging given the overlapping mechanisms that dictate chemotherapy efficacy and toxicity. Here, we report on a novel dietary intervention that, due to its localized gastrointestinal effects, is able to protect the intestinal mucosal from unwanted toxicity without impairing the anti-tumor effects of chemotherapy. The test diet (containing extensively hydrolyzed whey protein and medium chain triglycerides (MCTs)), was investigated in both tumor-naïve and tumor-bearing models to evaluate its effect on GI-M and chemo-efficacy, respectively. In both models, methotrexate was used as the representative chemotherapeutic agent and the diet was provided ad libitum for 14 days prior to treatment. GI-M was measured using the validated biomarker plasma citrulline, and chemo-efficacy defined by tumor burden (cm3/g body weight). The test diet significantly attenuated GI-M (P = 0.03), with associated reductions in diarrhea (P < 0.0001), weight loss (P < 0.05), daily activity (P < 0.02) and maintenance of body composition (P < 0.02). Moreover, the test diet showed significant impact on gut microbiota by increasing diversity and resilience, whilst also altering microbial composition and function (indicated by cecal short and brained chain fatty acids). The test diet did not impair the efficacy of methotrexate against mammary adenocarcinoma (tumor) cells. In line with the first model, the test diet minimized intestinal injury (P = 0.001) and diarrhea (P < 0.0001). These data support translational initiatives to determine the clinical feasibility, utility and efficacy of this diet to improve chemotherapy treatment outcomes.

Precarious work at a surgical center: implications for the organization and for the health of nursing workers.

OBJECTIVES: to analyze the implications of precarious work for the organization of work and for the health of nursing professionals in a surgical center. METHODS: qualitative, descriptive study in which the interview technique was applied on 30 nursing professionals from a surgical center in a university hospital located in the Southeast region of Brazil. The project was approved by the research ethics committee. Thematic content analysis was applied in the categorization of speeches. RESULTS: precarious work in the surgical center negatively affects the organization of work due to staff turnover, loss of skilled talent, and the need for continuous training of temporary workers. It also affects the quality of care, leading to risks to patient safety and workers' health.Final Considerations: it is important to make work conditions less precarious in order to minimize staff turnover and promote the quality of the service offered and the health of the worker.

Hepatic Coma Secondary to Fontan Conduit Thrombosis.

Introduction: The Fontan procedure is used to treat congenital heart defects and has improved long-term survival. Long-term complications include liver disease due to congestive hepatopathy. Fontan-related cirrhosis can manifest with ascites, gastrointestinal bleeding and encephalopathy. Case description: A 43-year-old man with history of Fontan surgery was admitted with COVID-19 pneumonia. There was rapid clinical and neurological deterioration, with coma and shock. CT imaging showed thrombosis of the Fontan conduit. The patient was successfully subjected to recanalization of the Fontan circulation, with progressive improvement of coma. Discussion: Fontan-associated liver disease is a major complication following the Fontan procedure. Clinicians must be aware of this pathology during patient follow-up. LEARNING POINTS: The Fontan procedure has improved the long-term survival of patients with single ventricle pathology.Fontan-associated liver disease is a result of haemodynamic changes associated with Fontan circulation; complications include hepatic encephalopathy and coma.Patients with Fontan circulation should be evaluated over time in order prevent and treat systemic complications.

Peroxisomes and Viruses: Overview on Current Knowledge and Experimental Approaches.

The general interest in the study of the interplay between peroxisomes and viruses has increased in recent years, with different reports demonstrating that distinct viruses modulate peroxisome-related mechanisms to either counteract the cellular antiviral response or support viral propagation. Nevertheless, mechanistical details are still scarce, and information is often incomplete. In this chapter, we present an overview of the current knowledge concerning the interplay between peroxisomes and different viruses. We furthermore present, compare, and discuss the most relevant experimental approaches and tools used in the different studies. Finally, we stress the importance of further, more detailed, and spatial-temporal analyses that encompass all the different phases of the viruses' infection cycles. These studies may lead to the discovery of novel peroxisome-related cellular mechanisms that can further be explored as targets for the development of novel antiviral therapies.

Tools to Investigate the Peroxisome-Dependent Antiviral Response.

The importance of peroxisomes in the context of viral infections has been increasingly demonstrated in recent years. The discovery that MAVS localizes at peroxisomes and that peroxisomal and mitochondrial MAVS perform complementing functions within the antiviral response has raised the interest in studying the peroxisome-dependent signaling in the context of infection by different viruses. To that end, specific experimental procedures should be applied, taking into consideration the endogenous localization of MAVS at both organelles. The analysis of peroxisomal MAVS activation requires, hence, the preliminar generation and validation of cell lines where MAVS localizes solely at peroxisomes, as well as other specific cellular tools. Here, we present a detailed protocol to analyse the peroxisome-dependent antiviral response, using virus-specific and virus-unspecific stimuli.

Determining the Importance of Peroxisomal Proteins for Viral Infections in Cultured Mammalian Cells.

Peroxisomes have recently been shown to play important roles in the context of viral infections. However, further and more detailed studies should be performed to unravel the specific mechanisms involved. The analysis of the relevance of particular peroxisomal components, such as peroxisomal proteins, for viral infections can be performed by comparing the production of new virus particles in the absence and presence of those specific components. Different methodologies are used to quantify the production of infectious virus particles, depending on the virus, cell type, and the specific characteristics of the viral infection to be analyzed. Here we provide a detailed protocol to study the importance of a putative peroxisomal protein on infection by viruses that induce the death of their host cells. We use the influenza A virus (IAV) infection in A549 cells as a model, and the quantification of the newly produced infectious virus particles is performed by a plaque assay.

The Unusual Aggregation and Fusion Activity of the Antimicrobial Peptide W-BP100 in Anionic Vesicles.

Cationic antimicrobial peptides (CAMPs) offer a promising strategy to counteract bacterial resistance, mostly due to their membrane-targeting activity. W-BP100 is a potent broad-spectrum cecropin-melittin CAMP bearing a single N-terminal Trp, which was previously found to improve its antibacterial activity. W-BP100 has high affinity toward anionic membranes, inducing membrane saturation at low peptide-to-lipid (P/L) ratios and membrane permeabilization, with the unique property of promoting the aggregation of anionic vesicles only at specific P/L ratios. Herein, we aimed to investigate this unusual behavior of W-BP100 by studying its aggregation and fusion properties with negatively-charged large (LUVs) or giant (GUVs) unilamellar vesicles using biophysical tools. Circular dichroism (CD) showed that W-BP100 adopted an α-helical conformation in anionic LUVs, neutralizing its surface charge at the aggregation P/L ratio. Its fusion activity, assessed by Förster resonance energy transfer (FRET) using steady-state fluorescence spectroscopy, occurred mainly at the membrane saturation/aggregation P/L ratio. Confocal microscopy studies confirmed that W-BP100 displays aggregation and detergent-like effects at a critical P/L ratio, above which it induces the formation of new lipid aggregates. Our data suggest that W-BP100 promotes the aggregation and fusion of anionic vesicles at specific P/L ratios, being able to reshape the morphology of GUVs into new lipid structures.