IOTA-Based Distributed Ledger in the Mining Industry: Efficiency, Sustainability and Transparency.

The paper presents a traceability framework founded upon a methodological approach specifically designed for the integration of the IOTA-based distributed ledger within the mining industry. This framework constitutes an initial stride towards the certification and labelling of sustainable material production. The efficacy of this methodology is subject to real-world evaluation within the framework of the European Commission funded project DIG_IT. Within the architectural framework, the integration of decentralized identifiers (DIDs) and the IOTA network are instrumental in effecting the encryption of data records, with associated hashes securely anchored on the explorer. Recorded environmental parameters, encompassing metrics such as pH level, turbidity, electrical conductivity, and emissions, serve as tangible evidence affirming their adherence to prevailing regulatory standards. The overarching system architecture encompasses a sophisticated Industrial Internet of Things platform (IIoTp), facilitating the seamless connection of data from a diverse array of sensors. End users, including governmental entities, mining managers, and the general public, stand to derive substantial benefits from tailored dashboards designed to facilitate the validation of data for emission compliance.

Índice biespectral y tasa de supresión tras parada cardiaca: ¿son útiles para individualizar planes de escalada terapéutica? / Bispectral index and suppression ratio after cardiac arrest: are they useful as bedside tools for rational treatment escalation plans?

Introducción y objetivos: La disfunción miocárdica contribuye a la mortalidad precoz (24-72 horas) de los supervivientes de parada cardiaca (PC). Actualmente, la decisión de implantar un dispositivo de soporte circulatorio en este contexto se toma con información limitada acerca del potencial de recuperación neurológica (PRN) del paciente, lo que en muchas ocasiones termina en infratratamiento. Por tanto, requerimos de herramientas accesibles y fiables que añadan información sobre el PRN y ayuden a establecer planes individualizados de escalada terapéutica. Métodos: Se recogieron valores de índice biespectral (BIS) y tasa de supresión (TS) en supervivientes de una PC sometidos a control de la temperatura corporal. La función neurológica se evaluó con la escala Cerebral Performance Category (CPC). Resultados: Se incluyeron 340 pacientes. En la primera evaluación neurológica completa, 211 (62,1%) alcanzaron buen pronóstico (CPC 1-2). Los valores de BIS fueron significativamente mayores y los de TS menores, en pacientes con CPC 1-2. Un BIS promedio> 26 en las primeras 12 horas predijo buena evolución neurológica (sensibilidad 89,5%; especificidad 75,8%; AUC=0,869), mientras que una TS promedio> 24 en las primeras 12 horas predijo mala evolución o CPC 3-5 (sensibilidad 91,5%; especificidad 81,8%; AUC=0,906). Los valores horarios de BIS/TS mostraron buena capacidad predictiva (AUC> 0,85) desde la 2.a hora para TS y 4.a para BIS. Conclusiones: El BIS/TS permiten estimar el PRN tras una PC. Este hallazgo puede contribuir a crear conciencia con respecto a evitar la limitación de escalada terapéutica en pacientes potencialmente recuperables.(AU)

Introduction and objectives: Myocardial dysfunction contributes to early mortality (24-72 hours) among survivors of a cardiac arrest (CA). The benefits of mechanical support in refractory shock should be balanced against the patient's potential for neurological recovery. To date, these early treatment decisions have been taken based on limited information leading mainly to undertreatment. Therefore, there is a need for early, reliable, accessible, and simple tools that offer information on the possibilities of neurological improvement. Methods: We collected data from bispectral index (BIS) and suppression ratio (SR) monitoring of adult comatose survivors of CA managed with targeted temperature management (TTM). Neurological status was assessed according to the Cerebral Performance Category (CPC) scale. Results: We included 340 patients. At the first full neurological evaluation, 211 patients (62.1%) achieved good outcome or CPC 1-2. Mean BIS values were significantly higher and median SR lower in patients with CPC 1-2. An average BIS> 26 during first 12hours of TTM predicted good outcome with 89.5% sensitivity and 75.8% specificity (AUC of 0.869), while average SR values> 24 during the first 12hours of TTM predicted poor outcome (CPC 3-5) with 91.5% sensitivity and 81.8% specificity (AUC, 0.906). Hourly BIS and SR values exhibited good predictive performance (AUC> 0.85), as soon as hour 2 for SR and hour 4 for BIS. Conclusions: BIS/SR are associated with patients’ potential for neurological recovery after CA. This finding could help to create awareness of the possibility of a better outcome in patients who might otherwise be wrongly considered as nonviable and to establish personalized treatment escalation plans.(AU)

Impact of the withdrawal of renin-angiotensin-aldosterone inhibitors on mortality in COVID-19 patients.

Background: Chronic use of Angiotensin-converting enzyme (ACE) inhibitors (ACEi) and aldosterone-receptor blockers (ARB) is not associated with worse outcomes in patients with COVID-19. However, evidence on the impact of their discontinuation during hospital admission is scarce. Our aim was to determine whether withdrawal of ACEi, ARB and mineralocorticoid receptor antagonists (MRA) is associated with all-cause mortality in a real-life large cohort of patients with SARS-CoV-2 infection. Methods: Observational cohort study from a large referral center from 1 March 2020 to 20 April 2020. Withdrawal of renin-angiotensin-aldosterone system inhibitors was defined as the absence of any received dose during hospital admission in patients receiving chronic treatment. Prescriptions during admission were confirmed by data from the central pharmacy computerized system. Results: A total of 2042 patients (mean age 68.4±17.6, 57.1% male) with confirmed COVID-19 were included. During a median follow-up of 57 (21-55) days, 583 (28.6%) died. Prior to hospital admission 468 (22.9%), 343 (16.8%) and 83 (4.1%) patients were receiving ACEi, ARB and MRA respectively. During the study period, 216 (46.2%), 193 (56.3%) and 41 (49.4%) were withdrawn from the corresponding drug. After adjusting for age, cardiovascular risk factors, baseline comorbidities and in-hospital COVID-19 dedicated treatment, withdrawal of ACE inhibitors (hazard ration [HR] 1.48 [95% confidence interval -CI- 1.16-1.89]) and MRA (HR 2.01 [95% CI 1.30-3.10]) were shown to be independent predictors of all-cause mortality. No independent relationship between ARB withdrawal and mortality was observed. Conclusion: ACEi and MRA withdrawal were associated with higher mortality. Strong consideration should be given to not discontinuing these medications during hospital admission.

Introdução: O uso crónico de inibidores da ECA (IECA) e de antagonistas dos recetores de aldosterona (ARA) não está associado a resultados piores em doentes com Covid-19. No entanto, a evidência relativa ao impacto da sua retirada durante a admissão hospitalar é escassa. O nosso objetivo foi determinar se a retirada do IECA, ARA e antagonistas dos recetores dos mineralocorticóides (ARM) está associada à mortalidade por todas as causas numa grande coorte real de doentes com infeção por SRA-CoV-2. Métodos: Estudo coorte observacional a partir de um grande centro de referência de 1 de março de 2020 a 20 de abril de 2020. A retirada dos inibidores do sistema RAAS foi definida como a ausência de qualquer dose recebida durante a admissão hospitalar em doentes que recebem tratamento prolongado. As prescrições durante a admissão foram confirmadas por dados do sistema informático da farmácia central. Resultados: Um total de 2042 doentes (idade média de 68,4 ±17,6, 57,1% do sexo masculino) com COVID-19 confirmado foram incluídos. Durante um acompanhamento médio de 57 (21-55) dias, 583 (28,6%) morreram. Conclusão: A retirada do IECA e do ARM foi associada a uma mortalidade mais elevada. Deve ser dada grande atenção para não interromper estes medicamentos durante a admissão hospitalar.

Bispectral index and suppression ratio after cardiac arrest: are they useful as bedside tools for rational treatment escalation plans?

INTRODUCTION AND OBJECTIVES: Myocardial dysfunction contributes to early mortality (24-72 hours) among survivors of a cardiac arrest (CA). The benefits of mechanical support in refractory shock should be balanced against the patient's potential for neurological recovery. To date, these early treatment decisions have been taken based on limited information leading mainly to undertreatment. Therefore, there is a need for early, reliable, accessible, and simple tools that offer information on the possibilities of neurological improvement. METHODS: We collected data from bispectral index (BIS) and suppression ratio (SR) monitoring of adult comatose survivors of CA managed with targeted temperature management (TTM). Neurological status was assessed according to the Cerebral Performance Category (CPC) scale. RESULTS: We included 340 patients. At the first full neurological evaluation, 211 patients (62.1%) achieved good outcome or CPC 1-2. Mean BIS values were significantly higher and median SR lower in patients with CPC 1-2. An average BIS> 26 during first 12 hours of TTM predicted good outcome with 89.5% sensitivity and 75.8% specificity (AUC of 0.869), while average SR values> 24 during the first 12 hours of TTM predicted poor outcome (CPC 3-5) with 91.5% sensitivity and 81.8% specificity (AUC, 0.906). Hourly BIS and SR values exhibited good predictive performance (AUC> 0.85), as soon as hour 2 for SR and hour 4 for BIS. CONCLUSIONS: BIS/SR are associated with patients' potential for neurological recovery after CA. This finding could help to create awareness of the possibility of a better outcome in patients who might otherwise be wrongly considered as nonviable and to establish personalized treatment escalation plans.

Characterization of myocardial injury in a cohort of patients with SARS-CoV-2 infection.

BACKGROUND: Myocardial injury has been identified as a common complication in patients with COVID-19. However, recent research has serious limitations, such as non-guideline definition of myocardial injury, heterogenicity of troponin sampling or very short-term follow-up. Using data from a large European cohort, we aimed to overcome these pitfalls and adequately characterize myocardial damage in COVID-19. METHODS: Consecutive patients with confirmed SARS-CoV-2 infection and available high-sensitive troponin I (hs-TnI), from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied. RESULTS: A total of 918 patients (mean age 63.2 ± 15.5 years, 60.1% male) with a median follow-up of 57 (49-63) days were included. Of these, 190 (20.7%) fulfilled strict criteria for myocardial injury (21.1% chronic, 76.8% acute non-ischemic, 2.1% acute ischemic). Time from onset of symptoms to maximum hs-TnI was 11 (7-18) days. Thrombotic and bleeding events, arrhythmias, heart failure, need for mechanical ventilation and death were significantly more prevalent in patients with higher hs-TnI concentrations, even without fulfilling criteria for myocardial injury. hs-TnI was identified as an independent predictor of mortality [HR 2.52 (1.57-4.04) per 5-logarithmic units increment] after adjusting for multiple relevant covariates. CONCLUSION: Elevated hs-TnI is highly prevalent among patients with SARS-CoV-2 infection. Even mild elevations well below the 99th URL were significantly associated with higher rates of cardiac and non-cardiac complications, and higher mortality. Future research should address the role of serial hs-TnI assessment to improve COVID-19 prognostic stratification and clinical outcomes.

ANTECEDENTES: El daño miocárdico parece una complicación frecuente en pacientes con COVID-19. Sin embargo, la literatura al respecto presenta serias limitaciones, como definiciones incorrectas, heterogeneidad de las determinaciones de troponina o seguimientos cortos. Utilizando datos de una cohorte amplia, el objetivo del trabajo fue caracterizar adecuadamente el daño miocárdico en pacientes con COVID-19 utilizando una metodología adecuada. MÉTODOS: Se estudió a pacientes consecutivos con infección confirmada y determinaciones disponibles de troponina I de alta sensibilidad (hs-TnI), desde el 1 de marzo hasta el 20 de abril del 2020, que hubieran completado al menos un mes de seguimiento o fallecieran durante el periodo de estudio. RESULTADOS: Se incluyó a 918 pacientes (edad 63,2 ± 15,5 años, 60,1% varones) con un seguimiento mediano de 57 (49-63) días. De estos, 190 (20,7%) cumplían criterios estrictos de lesión miocárdica (21,1% crónica, 76,8% aguda no isquémica, 2,1% aguda isquémica). El tiempo desde el inicio de los síntomas hasta la hs-TnI máxima fue de 11 (7-18) días. Los eventos trombóticos y hemorrágicos, las arritmias, la insuficiencia cardíaca, la necesidad de ventilación mecánica y la muerte fueron significativamente más frecuentes en pacientes con concentraciones elevadas de hs-TnI, incluso por debajo del nivel de lesión miocárdica. La hs-TnI resultó un predictor independiente de mortalidad (HR 2,52 [(1,57-4,04] por cada 5 unidades logarítmicas). CONCLUSIÓN: La hs-TnI elevada es altamente prevalente entre los pacientes con COVID-19. Elevaciones leves muy por debajo del límite para definir lesión miocárdica se asociaron con más complicaciones y mayor mortalidad. La determinación protocolizada de hs-TnI en estos enfermos podría mejorar su estratificación pronóstica y los resultados clínicos.

Characterization of myocardial injury in a cohort of patients with SARS-CoV-2 infection / Caracterización de la lesión miocárdica en una cohorte de pacientes infectados por el SARS-CoV-2

Background: Myocardial injury has been identified as a common complication in patients with COVID-19. However, recent research has serious limitations, such as non-guideline definition of myocardial injury, heterogenicity of troponin sampling or very short-term follow-up. Using data from a large European cohort, we aimed to overcome these pitfalls and adequately characterize myocardial damage in COVID-19.MethodsConsecutive patients with confirmed SARS-CoV-2 infection and available high-sensitive troponin I (hs-TnI), from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied.ResultsA total of 918 patients (mean age 63.2±15.5 years, 60.1% male) with a median follow-up of 57 (49–63) days were included. Of these, 190 (20.7%) fulfilled strict criteria for myocardial injury (21.1% chronic, 76.8% acute non-ischemic, 2.1% acute ischemic). Time from onset of symptoms to maximum hs-TnI was 11 (7–18) days. Thrombotic and bleeding events, arrhythmias, heart failure, need for mechanical ventilation and death were significantly more prevalent in patients with higher hs-TnI concentrations, even without fulfilling criteria for myocardial injury. hs-TnI was identified as an independent predictor of mortality [HR 2.52 (1.57–4.04) per 5-logarithmic units increment] after adjusting for multiple relevant covariates.ConclusionElevated hs-TnI is highly prevalent among patients with SARS-CoV-2 infection. Even mild elevations well below the 99th URL were significantly associated with higher rates of cardiac and non-cardiac complications, and higher mortality. Future research should address the role of serial hs-TnI assessment to improve COVID-19 prognostic stratification and clinical outcomes. (AU)

Antecedentes: El daño miocárdico parece una complicación frecuente en pacientes con COVID-19. Sin embargo, la literatura al respecto presenta serias limitaciones, como definiciones incorrectas, heterogeneidad de las determinaciones de troponina o seguimientos cortos. Utilizando datos de una cohorte amplia, el objetivo del trabajo fue caracterizar adecuadamente el daño miocárdico en pacientes con COVID-19 utilizando una metodología adecuada.MétodosSe estudió a pacientes consecutivos con infección confirmada y determinaciones disponibles de troponina I de alta sensibilidad (hs-TnI), desde el 1 de marzo hasta el 20 de abril del 2020, que hubieran completado al menos un mes de seguimiento o fallecieran durante el periodo de estudio.ResultadosSe incluyó a 918 pacientes (edad 63,2±15,5 años, 60,1% varones) con un seguimiento mediano de 57 (49-63) días. De estos, 190 (20,7%) cumplían criterios estrictos de lesión miocárdica (21,1% crónica, 76,8% aguda no isquémica, 2,1% aguda isquémica). El tiempo desde el inicio de los síntomas hasta la hs-TnI máxima fue de 11 (7-18) días. Los eventos trombóticos y hemorrágicos, las arritmias, la insuficiencia cardíaca, la necesidad de ventilación mecánica y la muerte fueron significativamente más frecuentes en pacientes con concentraciones elevadas de hs-TnI, incluso por debajo del nivel de lesión miocárdica. La hs-TnI resultó un predictor independiente de mortalidad (HR 2,52 [(1,57-4,04] por cada 5 unidades logarítmicas).ConclusiónLa hs-TnI elevada es altamente prevalente entre los pacientes con COVID-19. Elevaciones leves muy por debajo del límite para definir lesión miocárdica se asociaron con más complicaciones y mayor mortalidad. La determinación protocolizada de hs-TnI en estos enfermos podría mejorar su estratificación pronóstica y los resultados clínicos. (AU)

Characterization of myocardial injury in a cohort of patients with SARS-CoV-2 infection.

BACKGROUND: Myocardial injury has been identified as a common complication in patients with COVID-19. However, recent research has serious limitations, such as non-guideline definition of myocardial injury, heterogenicity of troponin sampling or very short-term follow-up. Using data from a large European cohort, we aimed to overcome these pitfalls and adequately characterize myocardial damage in COVID-19. METHODS: Consecutive patients with confirmed SARS-CoV-2 infection and available high-sensitive troponin I (hs-TnI), from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied. RESULTS: A total of 918 patients (mean age 63.2±15.5 years, 60.1% male) with a median follow-up of 57 (49-63) days were included. Of these, 190 (20.7%) fulfilled strict criteria for myocardial injury (21.1% chronic, 76.8% acute non-ischemic, 2.1% acute ischemic). Time from onset of symptoms to maximum hs-TnI was 11 (7-18) days. Thrombotic and bleeding events, arrhythmias, heart failure, need for mechanical ventilation and death were significantly more prevalent in patients with higher hs-TnI concentrations, even without fulfilling criteria for myocardial injury. hs-TnI was identified as an independent predictor of mortality [HR 2.52 (1.57-4.04) per 5-logarithmic units increment] after adjusting for multiple relevant covariates. CONCLUSION: Elevated hs-TnI is highly prevalent among patients with SARS-CoV-2 infection. Even mild elevations well below the 99th URL were significantly associated with higher rates of cardiac and non-cardiac complications, and higher mortality. Future research should address the role of serial hs-TnI assessment to improve COVID-19 prognostic stratification and clinical outcomes.

Prediction of thromboembolic events and mortality by the CHADS2 and the CHA2DS2-VASc in COVID-19.

AIMS: Age, sex, and cardiovascular disease have been linked to thromboembolic complications and poorer outcomes in COVID-19. We hypothesize that CHADS2 and CHA2DS2-VASc scores may predict thromboembolic events and mortality in COVID-19. METHODS AND RESULTS: COVID-19 hospitalized patients with confirmed SARS-CoV-2 infection from 1 March to 20 April 2020 who completed at least 1-month follow-up or died were studied. CHADS2 and CHA2DS2-VASc scores were calculated. Given the worse prognosis of male patients in COVID-19, a modified CHA2DS2-VASc score (CHA2DS2-VASc-M) in which 1 point was given to male instead of female was also calculated. The associations of these scores with laboratory results, thromboembolic events, and death were analysed. A total of 3042 patients (mean age 62.3 ± 20.3 years, 54.9% male) were studied and 115 (3.8%) and 626 (20.6%) presented a definite thromboembolic event or died, respectively, during the study period [median follow 59 (50-66) days]. Higher score values were associated with more marked abnormalities of inflammatory and cardiac biomarkers. Mortality was significantly higher with increasing scores for CHADS2, CHA2DS2-VASc, and CHA2DS2-VASc-M (P < 0.001 for trend). The CHA2DS2-VASc-M showed the best predictive value for mortality [area under the receiver operating characteristic curve (AUC) 0.820, P < 0.001 for comparisons]. All scores had poor predictive value for thromboembolic events (AUC 0.497, 0.490, and 0.541, respectively). CONCLUSION: The CHADS2, CHA2DS2-VASc, and CHA2DS2-VASc-M scores are significantly associated with all-cause mortality but not with thromboembolism in COVID-19 patients. They are simple scoring systems in everyday use that may facilitate initial 'quick' prognostic stratification in COVID-19.

Characterization of NT-proBNP in a large cohort of COVID-19 patients.

AIMS: Extensive research regarding the association of troponin and prognosis in coronavirus disease 2019 (COVID-19) has been performed. However, data regarding natriuretic peptides are scarce. N-terminal pro B-type natriuretic peptide (NT-proBNP) reflects haemodynamic stress and has proven useful for risk stratification in heart failure (HF) and other conditions such as pulmonary embolism and pneumonia. We aimed to adequately characterize NT-proBNP concentrations using a large cohort of patients with COVID-19, and to investigate its association with prognosis. METHODS AND RESULTS: Consecutive patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and available NT-proBNP determinations, from March 1st to April 20th, 2020 who completed at least 1-month follow-up or died, were studied. Of 3080 screened patients, a total of 396 (mean age 71.8 ± 14.6 years, 61.1% male) fulfilled all the selection criteria and were finally included, with a median follow-up of 53 (18-62) days. Of those, 192 (48.5%) presented NT-proBNP levels above the recommended cut-off for the identification of HF. However, only 47 fulfilled the clinical criteria for the diagnosis of HF. Patients with higher NT-proBNP during admission experienced more frequent bleeding, arrhythmias and HF decompensations. NT-proBNP was associated with mortality both in the whole study population and after excluding patients with HF. A multivariable Cox model confirmed that NT-proBNP was independently associated with mortality after adjusting for all relevant confounders (hazard ratio 1.28, 95% confidence interval 1.13-1.44, per logarithmic unit). CONCLUSION: NT-proBNP is frequently elevated in COVID-19. It is strongly and independently associated with mortality after adjusting for relevant confounders, including chronic HF and acute HF. Therefore, its use may improve early prognostic stratification in this condition.

Heart failure in COVID-19 patients: prevalence, incidence and prognostic implications.

AIMS: Data on the impact of COVID-19 in chronic heart failure (CHF) patients and its potential to trigger acute heart failure (AHF) are lacking. The aim of this work was to study characteristics, cardiovascular outcomes and mortality in patients with confirmed COVID-19 infection and a prior diagnosis of heart failure (HF). Further aims included the identification of predictors and prognostic implications for AHF decompensation during hospital admission and the determination of a potential correlation between the withdrawal of HF guideline-directed medical therapy (GDMT) and worse outcomes during hospitalization. METHODS AND RESULTS: Data for a total of 3080 consecutive patients with confirmed COVID-19 infection and follow-up of at least 30 days were analysed. Patients with a previous history of CHF (n = 152, 4.9%) were more prone to the development of AHF (11.2% vs. 2.1%; P < 0.001) and had higher levels of N-terminal pro brain natriuretic peptide. In addition, patients with previous CHF had higher mortality rates (48.7% vs. 19.0%; P < 0.001). In contrast, 77 patients (2.5%) were diagnosed with AHF, which in the vast majority of cases (77.9%) developed in patients without a history of HF. Arrhythmias during hospital admission and CHF were the main predictors of AHF. Patients developing AHF had significantly higher mortality (46.8% vs. 19.7%; P < 0.001). Finally, the withdrawal of beta-blockers, mineralocorticoid receptor antagonists and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was associated with a significant increase in in-hospital mortality. CONCLUSIONS: Patients with COVID-19 have a significant incidence of AHF, which is associated with very high mortality rates. Moreover, patients with a history of CHF are prone to developing acute decompensation after a COVID-19 diagnosis. The withdrawal of GDMT was associated with higher mortality.

Infarto agudo de miocardio secundario a infección por Plasmodium ovale / Acute myocardial infarction secondary to infection by Plasmodium ovale

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Antimicrobial activity of commercial calcium phosphate based materials functionalized with vanillin.

Infections represent one of the most frequent causes of arthroplasty revision. Thus, design of new antimicrobial scaffolds to reduce implant rejections, bone infections and associated medical costs is highly desired. In recent years, essential oil components (EOCs) have merged as compounds with significant antimicrobial activity that can be attached to specific surfaces to enhance and prolong their antimicrobial effect. Herein calcium phosphate CaP regenerative materials have been coated with a vanillin derivative to combine its original bone regeneration properties with antimicrobial action of EOCs. Materials in form of microparticles and blocks were prepared and fully characterized. Clonogenic viability tests demonstrated that low concentrations of material (10 mg·mL-1) resulted effective to kill 100% of E. coli DH5α bacteria. Additionally, vanillin containing scaffolds did not display any toxic effect over cells, yet they preserve the ability to express alkaline phosphatase (ALPL), collagen type 1, chain α1 (COL1A1) and bone gamma-carboxyglutamic acid-containing protein or osteocalcin (BGLAP), which are genes typically expressed by osteoblasts. These results demonstrate that commercially available scaffolds can be functionalized with EOCs, achieving antimicrobial activity and open up a new approach for the treatment and prevention of infection. STATEMENT OF SIGNIFICANCE: During the last years, the interest in bone regenerative materials with antibiotic properties has increased, since prosthesis infection is one of the most usual complications in implant surgery. In this work, we report a hybrid system composed by a calcium phosphate material (powders and scaffolds) functionalized with the derivative of an essential oil component (EOC). Our purpose was to provide the calcium phosphate material with antimicrobial activity without harming its bone regenerative capability. The obtained results were encouraging, which opens up the possibility of developing new modified materials for the prevention and treatment of bone infection.

Mesoporous Bioactive Glasses Equipped with Stimuli-Responsive Molecular Gates for Controlled Delivery of Levofloxacin against Bacteria.

An increase of bone diseases incidence has boosted the study of ceramic biomaterials as potential osteo-inductive scaffolds. In particular, mesoporous bioactive glasses have demonstrated to possess a broad application in the bone regeneration field, due their osteo-regenerative capability and their ability to release drugs from the mesoporous structure. These special features have been studied as an option to fight against bone infection, which is one of the most common problems regarding bone regeneration therapies. In this work, a mesoporous bioglass functionalized with polyamines and capped with adenosine triphosphate (ATP) as the molecular gate was developed for the controlled release of the antibiotic levofloxacin. Phosphate bonds of ATP were hydrolyzed in the presence of acid phosphatase (APase), the concentration of which is significantly increased in bone infection due to the activation of bone resorption processes. The solid was characterized and tested successfully against bacteria. The final gated solid induced bacterial death only in the presence of acid phosphatase. Additionally, it was demonstrated that the solid is not toxic against human cells. The double function of the prepared material as a drug delivery system and bone regeneration enhancer confirms the possible development of a new approach in the tissue engineering field, in which controlled release of therapeutic agents can be finely tuned and, at the same time, osteoinduction is favored.

Broadening the antibacterial spectrum of histidine kinase autophosphorylation inhibitors via the use of ε-poly-L-lysine capped mesoporous silica-based nanoparticles.

Two-component systems (TCS) regulate diverse processes such as virulence, stress responses, metabolism and antibiotic resistance in bacteria but are absent in humans, making them promising targets for novel antibacterials. By incorporating recently described TCS histidine kinase autophosphorylation inhibitors (HKAIs) into ε-poly-L-lysine capped nanoparticles (NPs) we could overcome the Gram negative (Gr-) permeability barrier for the HKAIs. The observed bactericidal activity against Gr- bacteria was shown to be due to the enhanced delivery and internalization of the HKAIs and not an inhibitory or synergistic effect of the NPs. The NPs had no adverse effects on mammalian cell viability or the immune function of macrophages in vitro and showed no signs of toxicity to zebrafish larvae in vivo. These results show that HKAIs are promising antibacterials for both Gr- and Gr+pathogens and that NPs are a safe drug delivery technology that can enhance the selectivity and efficacy of HKAIs against bacteria.

Molecular gates in mesoporous bioactive glasses for the treatment of bone tumors and infection.

Silica mesoporous nanomaterials have been proved to have meaningful application in biotechnology and biomedicine. Particularly, mesoporous bioactive glasses are recently gaining importance thanks to their bone regenerative properties. Moreover, the mesoporous nature of these materials makes them suitable for drug delivery applications, opening new lines in the field of bone therapies. In this work, we have developed innovative nanodevices based on the implementation of adenosine triphosphate (ATP) and ε-poly-l-lysine molecular gates using a mesoporous bioglass as an inorganic support. The systems have been previously proved to work properly with a fluorescence probe and subsequently with an antibiotic (levofloxacin) and an antitumoral drug (doxorubicin). The bioactivity of the prepared materials has also been tested, giving promising results. Finally, in vitro cell culture studies have been carried out; demonstrating that this gated devices can provide useful approaches for bone cancer and bone infection treatments. STATEMENT OF SIGNIFICANCE: Molecular-gated materials have recently been drawing attention due to their applications in fields as biomedicine and molecular recognition. For the first time as we are aware, we report herein a new enzymatic responsive molecular-gated device consisting in a mesoporous bioactive glass support implemented with two different molecular gates. Both controlled drug delivery properties and apatite-like phase formation ability of the device have been demonstrated, getting promising results. This approach opens up the possibility of developing new stimuli-responsive tailored bio-materials for bone cancer and infection treatments as well as regenerative bone grafts.

Towards the Development of Smart 3D "gated scaffolds" for on-command delivery.

A new approach towards the design of "gated scaffolds" based on the combination of capped mesoporous silica nanoparticles (MSNs) with porous biomaterials is reported. Using this approach, a 3D gelatin-based scaffold able to selectively deliver cargo in the presence of an APase enzyme is prepared and tested. This new design opens up the possibility of developing new smart biomaterials with advanced drug-delivery features.