Effective Apixaban removal using hemoadsorption during emergent open-heart surgery: a case report and narrative literature review.

BACKGROUND: The management of hemostasis in patients medicated with apixaban (Eliquis) undergoing emergency cardiac surgery is exceedingly difficult. The body's natural elimination pathways for apixaban prove ineffective in emergency situations, and the impact of hemodialysis is limited. The application of Cytosorb® may attenuate the concentration of apixaban, thereby facilitating the stabilization of these patients. CASE PRESENTATION: An 84-year-old man treated with apixaban, underwent emergency ascending aorta replacement surgery due to an acute type A aortic dissection. To address the challenges induced by apixaban, we integrated Cytosorb® cartridge into the Cardiopulmonary bypass circuit. There was a 63.7% decrease in perioperative apixaban-specific anti-factor Xa activity. The patient's postoperative course was favourable. CONCLUSION: Hemoadsorption with Cytosorb® may offers a safe and feasible approach for reducing apixaban concentration in emergency cardiac surgery, thereby mitigating the risk of hemorrhagic complications.

Hemoperfusion in Cardiac Surgery and ECMO.

Extracorporeal circulation (ECC) such as cardiopulmonary bypass or extracorporeal membrane oxygenation (ECMO) may induce a complex activation of the immune system. To date, strategies to mitigate this activation have failed to translate into meaningful improvement of clinical outcomes. Hemoperfusion is a blood purification technique, which relies on mass separation by a solid agent (hemoadsorption). It can be performed by adding a cartridge filled with adsorptive sorbent in the extracorporeal circuit. These devices have the theoretical advantage to enable the removal of excess pro- and anti-inflammatory molecules. Several studies have demonstrated the feasibility and safety of hemoperfusion during cardiac surgery. They have suggested that the procedure could decrease cytokine levels in situations where they were elevated. However, further studies are required to determine the clinical indications, timing, and duration of hemoperfusion during cardiac surgery. Although a similar rationale can apply to hemoperfusion in ECMO, available data in this situation are even more limited and results are conflicting. In this chapter, we discuss the rationale for hemoperfusion with ECC, how to practically do it, and the current level of evidence supporting this therapy.

O que mudou entre os períodos de pico e de platô durante a primeira onda do SARS-CoV-2? Estudo multicêntrico português em unidades de cuidados intensivos / What changed between the peak and plateau periods of the first COVID-19 pandemic wave? A multicentric Portuguese cohort study in intensive care

RESUMO Objetivo: Analisar e comparar as características de pacientes críticos com a COVID-19, a abordagem clínica e os resultados entre os períodos de pico e de platô na primeira onda pandêmica em Portugal. Métodos: Este foi um estudo de coorte multicêntrico ambispectivo, que incluiu pacientes consecutivos com a forma grave da COVID-19 entre março e agosto de 2020 de 16 unidades de terapia intensiva portuguesas. Definiram-se as semanas 10 - 16 e 17 - 34 como os períodos de pico e platô. Resultados: Incluíram-se 541 pacientes adultos com mediana de idade de 65 [57 - 74] anos, a maioria do sexo masculino (71,2%). Não houve diferenças significativas na mediana de idade (p = 0,3), no Simplified Acute Physiology Score II (40 versus 39; p = 0,8), na pressão parcial de oxigênio/fração inspirada de oxigênio (139 versus 136; p = 0,6), na terapia com antibióticos na admissão (57% versus 64%; p = 0,2) ou na mortalidade aos 28 dias (24,4% versus 22,8%; p = 0,7) entre o período de pico e platô. Durante o período de pico, os pacientes tiveram menos comorbidades (1 [0 - 3] versus 2 [0 - 5]; p = 0,002); fizeram mais uso de vasopressores (47% versus 36%; p < 0,001) e ventilação mecânica invasiva na admissão (58,1% versus 49,2%; p < 0,001), e tiveram mais prescrição de hidroxicloroquina (59% versus 10%; p < 0,001), lopinavir/ritonavir (41% versus 10%; p < 0,001) e posição prona (45% versus 36%; p = 0,04). Entretanto, durante o platô, observou-se maior uso de cânulas nasais de alto fluxo (5% versus 16%; p < 0,001) na admissão, remdesivir (0,3% versus 15%; p < 0,001) e corticosteroides (29% versus 52%; p < 0,001), além de menor tempo de internação na unidade de terapia intensiva (12 versus 8 dias; p < 0,001). Conclusão: Houve mudanças significativas nas comorbidades dos pacientes, nos tratamentos da unidade de terapia intensiva e no tempo de internação entre os períodos de pico e platô na primeira onda da COVID-19.

ABSTRACT Objective: To analyze and compare COVID-19 patient characteristics, clinical management and outcomes between the peak and plateau periods of the first pandemic wave in Portugal. Methods: This was a multicentric ambispective cohort study including consecutive severe COVID-19 patients between March and August 2020 from 16 Portuguese intensive care units. The peak and plateau periods, respectively, weeks 10 - 16 and 17 - 34, were defined. Results: Five hundred forty-one adult patients with a median age of 65 [57 - 74] years, mostly male (71.2%), were included. There were no significant differences in median age (p = 0.3), Simplified Acute Physiology Score II (40 versus 39; p = 0.8), partial arterial oxygen pressure/fraction of inspired oxygen ratio (139 versus 136; p = 0.6), antibiotic therapy (57% versus 64%; p = 0.2) at admission, or 28-day mortality (24.4% versus 22.8%; p = 0.7) between the peak and plateau periods. During the peak period, patients had fewer comorbidities (1 [0 - 3] versus 2 [0 - 5]; p = 0.002) and presented a higher use of vasopressors (47% versus 36%; p < 0.001) and invasive mechanical ventilation (58.1 versus 49.2%; p < 0.001) at admission, prone positioning (45% versus 36%; p = 0.04), and hydroxychloroquine (59% versus 10%; p < 0.001) and lopinavir/ritonavir (41% versus 10%; p < 0.001) prescriptions. However, a greater use of high-flow nasal cannulas (5% versus 16%, p < 0.001) on admission, remdesivir (0.3% versus 15%; p < 0.001) and corticosteroid (29% versus 52%, p < 0.001) therapy, and a shorter ICU length of stay (12 days versus 8, p < 0.001) were observed during the plateau. Conclusion: There were significant changes in patient comorbidities, intensive care unit therapies and length of stay between the peak and plateau periods of the first COVID-19 wave.

Temporary Right Ventricular Assist Device After Redo Aortic Valve Replacement And Heartmate 3tm Implantation - A Case Report.

The implantation of the left ventricular assist device Abbott HeartMate 3TM is being increasingly performed for management of end-stage heart failure. LVAD implantation might be associated with early or late right ventricular dysfunction. When severe, a temporary right ventricular support device may need to be implanted. However, these situations are associated with higher mortality. We report a successful case of temporary right ventricular support following HeartMate 3 implantation.

Septic shock 3.0 criteria application in severe COVID-19 patients: An unattended sepsis population with high mortality risk.

BACKGROUND: Coronavirus disease 2019 (COVID-19) can be associated with life-threatening organ dysfunction due to septic shock, frequently requiring intensive care unit (ICU) admission, respiratory and vasopressor support. Therefore, clear clinical criteria are pivotal for early recognition of patients more likely to need prompt organ support. Although most patients with severe COVID-19 meet the Sepsis-3.0 criteria for septic shock, it has been increasingly recognized that hyperlactatemia is frequently absent, possibly leading to an underestimation of illness severity and mortality risk. AIM: To identify the proportion of severe COVID-19 patients with vasopressor support requirements, with and without hyperlactatemia, and describe their clinical outcomes and mortality. METHODS: We performed a single-center prospective cohort study. All adult patients admitted to the ICU with COVID-19 were included in the analysis and were further divided into three groups: Sepsis group, without both criteria; Vasoplegic Shock group, with persistent hypotension and vasopressor support without hyperlactatemia; and Septic Shock 3.0 group, with both criteria. COVID-19 was diagnosed using clinical and radiologic criteria with a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive RT-PCR test. RESULTS: 118 patients (mean age 63 years, 87% males) were included in the analysis (n = 51 Sepsis group, n = 26 Vasoplegic Shock group, and n = 41 Septic Shock 3.0 group). SOFA score at ICU admission and ICU length of stay were different between the groups (P < 0.001). Mortality was significantly higher in the Vasoplegic Shock and Septic Shock 3.0 groups when compared with the Sepsis group (P < 0.001) without a significant difference between the former two groups (P = 0.713). The log rank tests of Kaplan-Meier survival curves were also different (P = 0.007). Ventilator-free days and vasopressor-free days were different between the Sepsis vs Vasoplegic Shock and Septic Shock 3.0 groups (both P < 0.001), and similar in the last two groups (P = 0.128 and P = 0.133, respectively). Logistic regression identified the maximum dose of vasopressor therapy used (AOR 1.046; 95%CI: 1.012-1.082, P = 0.008) and serum lactate level (AOR 1.542; 95%CI: 1.055-2.255, P = 0.02) as the major explanatory variables of mortality rates (R 2 0.79). CONCLUSION: In severe COVID-19 patients, the Sepsis 3.0 criteria of septic shock may exclude approximately one third of patients with a similarly high risk of a poor outcome and mortality rate, which should be equally addressed.

Structural Characterization of Mycobacterium abscessus Phosphopantetheine Adenylyl Transferase Ligand Interactions: Implications for Fragment-Based Drug Design.

Anti-microbial resistance is a rising global healthcare concern that needs urgent attention as growing number of infections become difficult to treat with the currently available antibiotics. This is particularly true for mycobacterial infections like tuberculosis and leprosy and those with emerging opportunistic pathogens such as Mycobacterium abscessus, where multi-drug resistance leads to increased healthcare cost and mortality. M. abscessus is a highly drug-resistant non-tuberculous mycobacterium which causes life-threatening infections in people with chronic lung conditions such as cystic fibrosis. In this study, we explore M. abscessus phosphopantetheine adenylyl transferase (PPAT), an enzyme involved in the biosynthesis of Coenzyme A, as a target for the development of new antibiotics. We provide structural insights into substrate and feedback inhibitor binding modes of M. abscessus PPAT, thereby setting the basis for further chemical exploration of the enzyme. We then utilize a multi-dimensional fragment screening approach involving biophysical and structural analysis, followed by evaluation of compounds from a previous fragment-based drug discovery campaign against M. tuberculosis PPAT ortholog. This allowed the identification of an early-stage lead molecule exhibiting low micro molar affinity against M. abscessus PPAT (Kd 3.2 ± 0.8 µM) and potential new ways to design inhibitors against this enzyme. The resulting crystal structures reveal striking conformational changes and closure of solvent channel of M. abscessus PPAT hexamer providing novel strategies of inhibition. The study thus validates the ligandability of M. abscessus PPAT as an antibiotic target and identifies crucial starting points for structure-guided drug discovery against this bacterium.

Predictive value of D-dimer in the clinical outcome of severe COVID19 patients: Are we giving it too much credit?

BACKGROUND: COVID-19 is a new form of acute respiratory failure leading to multiorgan failure and ICU admission. Gathered evidence suggests that a 3-fold rise in D-dimer concentrations may be linked to poor prognosis and higher mortality. PURPOSE: To describe D-dimer admission profile in severe ICU COVID19 patients and its predictive role in outcomes and mortality. METHODS: Single-center retrospective cohort study. All adult patients admitted to ICU with COVID19 were divided into 3 groups: (1) Lower-values group (D-dimer levels < 3-fold normal range value [NRV] [500ng/mL]), Intermediate-values group (D-dimer ≥3-fold and <10-fold NRV) and Higher-value group (≥10-fold NRV). RESULTS: 118 patients (mean age 63 years, 73% males) were included (N = 73 Lower-values group, N = 31 Intermediate-values group; N = 11 Higher-values group). Mortality was not different between groups (p = 0.51). Kaplan-Meier survival curves revealed no differences (p = 0.52) between groups, nor it was verified even when gender, age, ICU length of stay, and SOFA score were considered as covariables. CONCLUSIONS: In severe COVID19 patients, the D-dimer profile does not retain a predictive value regarding patients' survivability and should not be used as a surrogate of disease severity.

Development of Inhibitors of SAICAR Synthetase (PurC) from Mycobacterium abscessus Using a Fragment-Based Approach.

Mycobacterium abscessus (Mab) has emerged as a challenging threat to individuals with cystic fibrosis. Infections caused by this pathogen are often impossible to treat due to the intrinsic antibiotic resistance leading to lung malfunction and eventually death. Therefore, there is an urgent need to develop new drugs against novel targets in Mab to overcome drug resistance and subsequent treatment failure. In this study, SAICAR synthetase (PurC) from Mab was identified as a promising target for novel antibiotics. An in-house fragment library screen and a high-throughput X-ray crystallographic screen of diverse fragment libraries were explored to provide crucial starting points for fragment elaboration. A series of compounds developed from fragment growing and merging strategies, guided by crystallographic information and careful hit-to-lead optimization, have achieved potent nanomolar binding affinity against the enzyme. Some compounds also show a promising inhibitory effect against Mab and Mtb. This work utilizes a fragment-based design and demonstrates for the first time the potential to develop inhibitors against PurC from Mab.

Discovery of Novel Inhibitors of Uridine Diphosphate-N-Acetylenolpyruvylglucosamine Reductase (MurB) from Pseudomonas aeruginosa, an Opportunistic Infectious Agent Causing Death in Cystic Fibrosis Patients.

Pseudomonas aeruginosa is of major concern for cystic fibrosis patients where this infection can be fatal. With the emergence of drug-resistant strains, there is an urgent need to develop novel antibiotics against P. aeruginosa. MurB is a promising target for novel antibiotic development as it is involved in the cell wall biosynthesis. MurB has been shown to be essential in P. aeruginosa, and importantly, no MurB homologue exists in eukaryotic cells. A fragment-based drug discovery approach was used to target Pa MurB. This led to the identification of a number of fragments, which were shown to bind to MurB. One fragment, a phenylpyrazole scaffold, was shown by ITC to bind with an affinity of Kd = 2.88 mM (LE 0.23). Using a structure guided approach, different substitutions were synthesized and the initial fragment was optimized to obtain a small molecule with Kd = 3.57 µM (LE 0.35).

Factors associated with immunization against hepatitis B among primary health care professionals.

Introduction: The hepatitis B virus is the cause of one of the major public health problems worldwide. The infection may affect the entire population equally; however, health care professionals are part of a group that is more vulnerable to the disease, since they are exposed to both occupational and daily hazards. Objectives: To investigate the prevalence and factors associated with the immunization of health care professionals against the hepatitis virus type B, in the city of Montes Claros, state of Minas Gerais, Brazil. Methods: This was a cross-sectional and quantitative study, conducted with primary health care professionals. Using a random cluster sampling, 209 medical professionals, nurses, and nursing technicians who were interested in participating in the research were selected. A structured questionnaire was applied, and blood sampling was performed for the analysis of hepatitis B surface antibody titers. Finally, a descriptive and bivariate statistical analysis was conducted. Results: Data have shown that 91.8% of the professionals had complete immunization against the hepatitis B virus, that is, they had taken the three recommended doses of the vaccine. However, 13.9% of the sample, even after vaccination, was non-reactive (titers < 10 IU/mL hepatitis B surface antibody). Most of the professionals (94.3%) had direct contact with needlesticks/sharps at work and none of the participants reported a previous infection by the virus. Conclusions: Although most participants had complete immunization, the total result of individuals who did not obtain seroconversion was eminent, so the importance of the hepatitis B surface antibody test must be disseminated in the context of public health.

Introdução: O vírus da hepatite B é o causador de um dos grandes problemas de saúde pública mundial. A infecção pode acometer toda a população de igual maneira; entretanto, os profissionais de saúde são parte de um grupo mais vulnerável à doença, visto que são expostos tanto ao risco ocupacional quanto ao risco cotidiano. Objetivos: Investigar a prevalência e os fatores associados à imunização de profissionais de saúde contra o vírus da hepatite viral tipo B na cidade de Montes Claros, Minas Gerais, Brasil. Métodos: Tratou-se de um estudo transversal e quantitativo, realizado com profissionais de saúde da atenção primária. Por amostragem aleatória por conglomerado, foram selecionados 209 profissionais médicos, enfermeiros e técnicos de enfermagem que tiveram interesse em participar da pesquisa. Foi aplicado um questionário estruturado, e foi realizada coleta de sangue para análise de títulos de anticorpo contra o antígeno de superfície da hepatite B. Por fim, a análise estatística descritiva e bivariada foi efetuada. Resultados: Os dados evidenciaram que 91,8% dos profissionais tinham imunização completa contra o vírus da hepatite B - ou seja, haviam tomado as três doses preconizadas da vacina. Entretanto, 13,9% da amostra, mesmo após a vacinação, se mostrou não reagente (títulos < 10 UI/mL de anticorpo contra o antígeno de superfície da hepatite B). A maioria (94,3%) dos profissionais tinha contato direto no trabalho com materiais perfurocortantes, e nenhum participante relatou infecção prévia pelo vírus. Conclusões: Apesar do fato de que a maioria dos participantes tinha imunização completa, o resultado total de indivíduos que não obtiveram soroconversão foi eminente, de modo que há de se divulgar a valia do exame de anticorpo contra o antígeno de superfície da hepatite B no contexto de saúde pública.

What changed between the peak and plateau periods of the first COVID-19 pandemic wave? A multicentric Portuguese cohort study in intensive care. / O que mudou entre os períodos de pico e de platô durante a primeira onda do SARS-CoV-2? Estudo multicêntrico português em unidades de cuidados intensivos.

OBJECTIVE: To analyze and compare COVID-19 patient characteristics, clinical management and outcomes between the peak and plateau periods of the first pandemic wave in Portugal. METHODS: This was a multicentric ambispective cohort study including consecutive severe COVID-19 patients between March and August 2020 from 16 Portuguese intensive care units. The peak and plateau periods, respectively, weeks 10 - 16 and 17 - 34, were defined. RESULTS: Five hundred forty-one adult patients with a median age of 65 [57 - 74] years, mostly male (71.2%), were included. There were no significant differences in median age (p = 0.3), Simplified Acute Physiology Score II (40 versus 39; p = 0.8), partial arterial oxygen pressure/fraction of inspired oxygen ratio (139 versus 136; p = 0.6), antibiotic therapy (57% versus 64%; p = 0.2) at admission, or 28-day mortality (24.4% versus 22.8%; p = 0.7) between the peak and plateau periods. During the peak period, patients had fewer comorbidities (1 [0 - 3] versus 2 [0 - 5]; p = 0.002) and presented a higher use of vasopressors (47% versus 36%; p < 0.001) and invasive mechanical ventilation (58.1 versus 49.2%; p < 0.001) at admission, prone positioning (45% versus 36%; p = 0.04), and hydroxychloroquine (59% versus 10%; p < 0.001) and lopinavir/ritonavir (41% versus 10%; p < 0.001) prescriptions. However, a greater use of high-flow nasal cannulas (5% versus 16%, p < 0.001) on admission, remdesivir (0.3% versus 15%; p < 0.001) and corticosteroid (29% versus 52%, p < 0.001) therapy, and a shorter ICU length of stay (12 days versus 8, p < 0.001) were observed during the plateau. CONCLUSION: There were significant changes in patient comorbidities, intensive care unit therapies and length of stay between the peak and plateau periods of the first COVID-19 wave.

OBJETIVO: Analisar e comparar as características de pacientes críticos com a COVID-19, a abordagem clínica e os resultados entre os períodos de pico e de platô na primeira onda pandêmica em Portugal. MÉTODOS: Este foi um estudo de coorte multicêntrico ambispectivo, que incluiu pacientes consecutivos com a forma grave da COVID-19 entre março e agosto de 2020 de 16 unidades de terapia intensiva portuguesas. Definiram-se as semanas 10 - 16 e 17 - 34 como os períodos de pico e platô. RESULTADOS: Incluíram-se 541 pacientes adultos com mediana de idade de 65 [57 - 74] anos, a maioria do sexo masculino (71,2%). Não houve diferenças significativas na mediana de idade (p = 0,3), no Simplified Acute Physiology Score II (40 versus 39; p = 0,8), na pressão parcial de oxigênio/fração inspirada de oxigênio (139 versus 136; p = 0,6), na terapia com antibióticos na admissão (57% versus 64%; p = 0,2) ou na mortalidade aos 28 dias (24,4% versus 22,8%; p = 0,7) entre o período de pico e platô. Durante o período de pico, os pacientes tiveram menos comorbidades (1 [0 - 3] versus 2 [0 - 5]; p = 0,002); fizeram mais uso de vasopressores (47% versus 36%; p < 0,001) e ventilação mecânica invasiva na admissão (58,1% versus 49,2%; p < 0,001), e tiveram mais prescrição de hidroxicloroquina (59% versus 10%; p < 0,001), lopinavir/ritonavir (41% versus 10%; p < 0,001) e posição prona (45% versus 36%; p = 0,04). Entretanto, durante o platô, observou-se maior uso de cânulas nasais de alto fluxo (5% versus 16%; p < 0,001) na admissão, remdesivir (0,3% versus 15%; p < 0,001) e corticosteroides (29% versus 52%; p < 0,001), além de menor tempo de internação na unidade de terapia intensiva (12 versus 8 dias; p < 0,001). CONCLUSÃO: Houve mudanças significativas nas comorbidades dos pacientes, nos tratamentos da unidade de terapia intensiva e no tempo de internação entre os períodos de pico e platô na primeira onda da COVID-19.

A fragment-based approach to assess the ligandability of ArgB, ArgC, ArgD and ArgF in the L-arginine biosynthetic pathway of Mycobacterium tuberculosis.

The L-arginine biosynthesis pathway consists of eight enzymes that catalyse the conversion of L-glutamate to L-arginine. Arginine auxotrophs (argB/argF deletion mutants) of Mycobacterium tuberculosis are rapidly sterilised in mice, while inhibition of ArgJ with Pranlukast was found to clear chronic M. tuberculosis infection in a mouse model. Enzymes in the arginine biosynthetic pathway have therefore emerged as promising targets for anti-tuberculosis drug discovery. In this work, the ligandability of four enzymes of the pathway ArgB, ArgC, ArgD and ArgF is assessed using a fragment-based approach. We identify several hits against these enzymes validated with biochemical and biophysical assays, as well as X-ray crystallographic data, which in the case of ArgB were further confirmed to have on-target activity against M. tuberculosis. These results demonstrate the potential for more enzymes in this pathway to be targeted with dedicated drug discovery programmes.

Targeting Mycobacterium tuberculosis CoaBC through Chemical Inhibition of 4'-Phosphopantothenoyl-l-cysteine Synthetase (CoaB) Activity.

Coenzyme A (CoA) is a ubiquitous cofactor present in all living cells and estimated to be required for up to 9% of intracellular enzymatic reactions. Mycobacterium tuberculosis (Mtb) relies on its own ability to biosynthesize CoA to meet the needs of the myriad enzymatic reactions that depend on this cofactor for activity. As such, the pathway to CoA biosynthesis is recognized as a potential source of novel tuberculosis drug targets. In prior work, we genetically validated CoaBC as a bactericidal drug target in Mtb in vitro and in vivo. Here, we describe the identification of compound 1f, a small molecule inhibitor of the 4'-phosphopantothenoyl-l-cysteine synthetase (PPCS; CoaB) domain of the bifunctional Mtb CoaBC, and show that this compound displays on-target activity in Mtb. Compound 1f was found to inhibit CoaBC uncompetitively with respect to 4'-phosphopantothenate, the substrate for the CoaB-catalyzed reaction. Furthermore, metabolomic profiling of wild-type Mtb H37Rv following exposure to compound 1f produced a signature consistent with perturbations in pantothenate and CoA biosynthesis. As the first report of a direct small molecule inhibitor of Mtb CoaBC displaying target-selective whole-cell activity, this study confirms the druggability of CoaBC and chemically validates this target.

Inhibiting Mycobacterium tuberculosis CoaBC by targeting an allosteric site.

Coenzyme A (CoA) is a fundamental co-factor for all life, involved in numerous metabolic pathways and cellular processes, and its biosynthetic pathway has raised substantial interest as a drug target against multiple pathogens including Mycobacterium tuberculosis. The biosynthesis of CoA is performed in five steps, with the second and third steps being catalysed in the vast majority of prokaryotes, including M. tuberculosis, by a single bifunctional protein, CoaBC. Depletion of CoaBC was found to be bactericidal in M. tuberculosis. Here we report the first structure of a full-length CoaBC, from the model organism Mycobacterium smegmatis, describe how it is organised as a dodecamer and regulated by CoA thioesters. A high-throughput biochemical screen focusing on CoaB identified two inhibitors with different chemical scaffolds. Hit expansion led to the discovery of potent and selective inhibitors of M. tuberculosis CoaB, which we show to bind to a cryptic allosteric site within CoaB.

Cytosorb® hemoadsorption of apixaban during emergent cardio-pulmonary bypass: a case report.

BACKGROUND: Peri-operative coagulation management of patients receiving apixaban, a new oral anticoagulant, is difficult. The CytoSorb® hemoadsorption device might represent a therapeutic option to reduce apixaban's pharmacological and inflammatory effects during high-risk surgery. CASE PRESENTATION: An 83-year-old woman treated with Apixaban underwent emergent redo mitral valve replacement for prosthetic valve endocarditis. A CytoSorb® cartridge was added to the cardio-pulmonary bypass (CPB) circuit. Apixaban-specific anti-factor Xa activity (AFXaA) were measured peri-operatively. After 100 minutes of CPB, a 50% AFXaA rate decrease was observed as compared to pre-CPB values. Furthermore, we noticed 39% and 44% reductions of AFXaA levels in comparison to the expected levels in patients with normal or altered renal function, respectively. CONCLUSION: Insertion of a CytoSorb® cartridge in the CPB was safe and associated with rapid correction of Apixaban-associated anticoagulation.

Atmospheric particulate matter from an industrial area as a source of metal nanoparticle contamination in aquatic ecosystems.

Air pollution legislation and control worldwide is based on the size of particulate matter (PM) to evaluate the effects on environmental and human health, in which the small diameter particles are considered more dangerous than larger sizes. This study investigates the composition, stability, size and dispersion of atmospheric settleable particulate matter (SePM) in an aqueous system. We aimed to interrogate the changes in the physical properties and characteristics that can contribute to increased metal uptake by aquatic biota. Samples collected in an area influenced by the steel and iron industry were separated into 8 fractions (425 to ≤10 µm) and analysed physically and chemically. Results from ICP-MS and X-ray showed that the PM composition was mainly hematite with 80% of Fe, followed by Al, Mn and Ti. Among 27 elements analysed we found 19 metals, showing emerging metallic contaminants such as Y, Zr, Sn, La, Ba and Bi. Scanning electron microscopy (SEM) showed that SePM fractions are formed by an agglomeration of nanoparticles. Furthermore, dynamic light scattering (DLS), zeta potential and nanoparticle tracking analysis (NTA) demonstrated that SPM were dissociated in water, forming nanoparticles smaller than 200 nm, which can also contribute to water pollution. This study highlights that SePM contamination may be substantially higher than expected under that allowed in atmospheric regulatory frameworks, thereby extending their negative effect to water bodies upon settling, which is an underexplored area of our knowledge. We therefore provide important insights for future investigations on safety regulations involving SePM in the environment, indicating the need to revise the role of SePM, not solely associated with air pollution but also considering their deleterious effects on water resources.

Trophic transfer of emerging metallic contaminants in a neotropical mangrove ecosystem food web.

Emerging metallic contaminants (EMCs) are of concern due their presence in aquatic ecosystems and the lack of environmental regulations in several countries. This study verifies the presence of EMCs in two neotropical mangrove estuarine ecosystems (Espírito Santo Brazil) by evaluating abiotic and biotic matrices across six trophic levels (plankton, oyster, shrimp, mangrove trees, crabs and fish) and hence interrogates the trophic transfer of these elements and their possible input sources. Using the oyster Crassostrea rhizophorae as a biomonitor, ten EMCs (Bi, Ce, La, Nb, Sn, Ta, Ti, W, Y and Zr) were determined. Bi input was from iron export and pelletizing industries; Ce, La and Y inputs were mainly associated with solid waste from steel production, while Zr, Nb and Ti were related to atmospheric particulate matter emissions. EMCs were detected at various trophic levels, showing biomagnification for most of them in the Santa Cruz estuary but biodilution in Vitória Bay. These contrasting results between the estuaries could be attributed to different pollution degrees, needing further research to be fully understood. This is the first report demonstrating EMCs trophic pathways in situ, constituting an essential baseline for future research and safety regulations involving EMCs in the environment.

Fragment-based discovery of a new class of inhibitors targeting mycobacterial tRNA modification.

Translational frameshift errors are often deleterious to the synthesis of functional proteins and could therefore be promoted therapeutically to kill bacteria. TrmD (tRNA-(N(1)G37) methyltransferase) is an essential tRNA modification enzyme in bacteria that prevents +1 errors in the reading frame during protein translation and represents an attractive potential target for the development of new antibiotics. Here, we describe the application of a structure-guided fragment-based drug discovery approach to the design of a new class of inhibitors against TrmD in Mycobacterium abscessus. Fragment library screening, followed by structure-guided chemical elaboration of hits, led to the rapid development of drug-like molecules with potent in vitro TrmD inhibitory activity. Several of these compounds exhibit activity against planktonic M. abscessus and M. tuberculosis as well as against intracellular M. abscessus and M. leprae, indicating their potential as the basis for a novel class of broad-spectrum mycobacterial drugs.