Nearly free silanols drive the interaction of crystalline silica polymorphs with membranes: Implications for mineral toxicity

Crystalline silica (CS) is a well-known hazardous material that causes severe diseases including silicosis, lung cancer, and autoimmune diseases. However, the hazard associated to crystalline silica is extremely variable and depends on some specific characteristics, including crystal structure and surface chemistry. The crystalline silica polymorphs share the SiO(2) stoichiometry and differentiate for crystal structure. The different crystal lattices in turn expose differently ordered hydroxyl groups at the crystal surface, i.e., the silanols. The nearly free silanols (NFS), a specific population of weakly interacting silanols, have been recently advanced as the key surface feature that governs recognition mechanisms between quartz and cell membrane, initiating toxicity. We showed here that the nearly free silanols occur on the other crystalline silica polymorphs and take part in the molecular interactions with biomembranes. A set of crystalline silica polymorphs, including quartz, cristobalite, tridymite, coesite, and stishovite, was physico-chemically characterized and the membranolytic activity was assessed using red blood cells as model membranes. Infrared spectroscopy in highly controlled conditions was used to profile the surface silanol topochemistry and the occurrence of surface nearly free silanols on crystalline silica polymorphs. All crystalline silica polymorphs, but stishovite were membranolytic. Notably, pristine stishovite did not exhibited surface nearly free silanols. The topochemistry of surface silanols was modulated by thermal treatments, and we showed that the occurrence of nearly free silanols paralleled the membranolytic activity for the crystalline silica polymorphs. These results provide a comprehensive understanding of the structure-activity relationship between nearly free silanols and membranolytic activity of crystalline silica polymorphs, offering a possible clue for interpreting the molecular mechanisms associated with silica hazard and bio-minero-chemical interfacial phenomena, including prebiotic chemistry

Disease-modifying treatments for patients with multiple sclerosis in Spain

Esclerosis múltiple; Polifarmacia; Interacciones medicamentosasEsclerosi múltiple; Polifarmàcia; Interaccions medicamentosesMultiple sclerosis; Polypharmacy; Drug interactionsLa esclerosis múltiple es una enfermedad desmielinizante crónica del sistema nervioso central y discapacitante a largo plazo. Existen diferentes tratamientos modificadores de la enfermedad. Estos pacientes, a pesar de ser generalmente jóvenes, tienen una elevada comorbilidad y riesgo de polimedicación por su compleja sintomatología y discapacidad. Objetivo principal determinar el tipo de tratamiento modificador de la enfermedad en los pacientes atendidos en servicios de farmacia de hospitales españoles. Objetivos secundarios Conocer los tratamientos concomitantes, determinar la prevalencia de la polifarmacia, identificar la prevalencia de interacciones y analizar la complejidad farmacoterapéutica. Método estudio observacional, transversal y multicéntrico. Se incluyeron todos los pacientes con diagnóstico de esclerosis múltiple y tratamiento modificador de la enfermedad activo a los que se atendió en las consultas de pacientes externos o en los hospitales de día durante la segunda semana de febrero 2021. Se recogieron: el tratamiento modificador, las comorbilidades y los tratamientos concomitantes para determinar el patrón de multimorbilidad, polifarmacia, complejidad farmacoterapéutica (Medication Regimen Complexity Index) e interacciones medicamentosas. Resultados se incluyeron 1.407 pacientes de 57 centros de 15 Comunidades Autónomas. La forma de presentación de la enfermedad más frecuente fue la forma remitente recurrente (89,3%). El tratamiento modificador de la enfermedad más prescrito fue dimetilfumarato (19,1%), seguido de teriflunomida (14,0%). De los tratamientos modificadores parenterales, los 2 más prescritos fueron el acetato de glatiramero y el natalizumab con un 11,1 y 10,8% respectivamente. El 24,7% de los pacientes tenían una comorbilidad y el 39,8% al menos 2 comorbilidades. El 13,3% pertenecía al menos a uno de los patrones definidos de multimorbilidad y el 16,5% pertenecían a 2 o más patrones. Los tratamientos concomitantes prescritos fueron los psicofármacos (35,5%), los antiepilépticos (13,9%) y los antihipertensivos y fármacos para enfermedades cardiovasculares (12,4%). La presencia de la polifarmacia fue del 32,7% y de la polifarmacia extrema el 8,1%. La prevalencia de interacciones fue del 14,8%. La mediana de complejidad farmacoterapéutica fue de 8,0 (IQR: 3,3 – 15,0). Conclusiones se ha descrito el tratamiento modificador de la enfermedad de los pacientes con esclerosis múltiple atendidos en los servicios de farmacia españoles y se ha caracterizado los tratamientos concomitantes, la prevalencia de polifarmacia, las interacciones, y su complejidad farmacoterapéutica.Multiple sclerosis is a chronic demyelinating disease of the central nervous system and long-term disabling. Different disease-modifying treatments are available. These patients, despite being generally young, have high comorbidity and risk of polymedication due to their complex symptomatology and disability. Objective primary To determine the type of disease-modifying treatment in patients seen in Spanish hospital pharmacy departments. Secondary objectives To determine concomitant treatments, determine the prevalence of polypharmacy, identify the prevalence of interactions and analyse pharmacotherapeutic complexity. Method Observational, cross-sectional, multicentre study. All patients with a diagnosis of multiple sclerosis and active disease-modifying treatment who were seen in outpatient clinics or day hospitals during the second week of February 2021 were included. Modifying treatment, comorbidities and concomitant treatments were collected to determine multimorbidity pattern, polypharmacy, pharmacotherapeutic complexity (Medication Regimen Complexity Index) and drug-drug interactions. Results 1,407 patients from 57 centres in 15 autonomous communities were included. The most frequent form of disease presentation was the relapsing remitting form (89.3%). The most prescribed disease-modifying treatment was dimethyl fumarate (19.1%), followed by teriflunomide (14.0%). Of the parenteral disease-modifying treatments, the two most prescribed were glatiramer acetate and natalizumab with 11.1% and 10.8%. 24.7% of the patients had one comorbidity and 39.8% had at least 2 comorbidities. 13.3% belonged to at least one of the defined patterns of multimorbidity and 16.5% belonged to 2 or more patterns. The concomitant treatments prescribed were psychotropic drugs (35.5%); antiepileptic drugs (13.9%) and antihypertensive drugs and drugs for cardiovascular pathologies (12.4%). The presence of polypharmacy was 32.7% and extreme polypharmacy 8.1%. The prevalence of interactions was 14.8%. Median pharmacotherapeutic complexity was 8.0 (IQR: 3.3 -- 15.0). Conclusions We have described the disease-modifying treatment of patients with multiple sclerosis seen in Spanish pharmacy services and characterised concomitant treatments, the prevalence of polypharmacy, interactions, and their complexity

Nearly free silanols drive the interaction of crystalline silica polymorphs with membranes: Implications for mineral toxicity

Crystalline silica (CS) is a well-known hazardous material that causes severe diseases including silicosis, lung cancer, and autoimmune diseases. However, the hazard associated to crystalline silica is extremely variable and depends on some specific characteristics, including crystal structure and surface chemistry. The crystalline silica polymorphs share the SiO2 stoichiometry and differentiate for crystal structure. The different crystal lattices in turn expose differently ordered hydroxyl groups at the crystal surface, i.e., the silanols. The nearly free silanols (NFS), a specific population of weakly interacting silanols, have been recently advanced as the key surface feature that governs recognition mechanisms between quartz and cell membrane, initiating toxicity. We showed here that the nearly free silanols occur on the other crystalline silica polymorphs and take part in the molecular interactions with biomembranes. A set of crystalline silica polymorphs, including quartz, cristobalite, tridymite, coesite, and stishovite, was physico-chemically characterized and the membranolytic activity was assessed using red blood cells as model membranes. Infrared spectroscopy in highly controlled conditions was used to profile the surface silanol topochemistry and the occurrence of surface nearly free silanols on crystalline silica polymorphs. All crystalline silica polymorphs, but stishovite were membranolytic. Notably, pristine stishovite did not exhibited surface nearly free silanols. The topochemistry of surface silanols was modulated by thermal treatments, and we showed that the occurrence of nearly free silanols paralleled the membranolytic activity for the crystalline silica polymorphs. These results provide a comprehensive understanding of the structure-activity relationship between nearly free silanols and membranolytic activity of crystalline silica polymorphs, offering a possible clue for interpreting the molecular mechanisms associated with silica hazard and bio-minero-chemical interfacial phenomena, including prebiotic chemistry

Extending the pool of compatible peptide hydrogels for protein crystallization

Short-peptide supramolecular (SPS) hydrogels are a class of materials that have been found to be useful for (bio)technological applications thanks to their biocompatible nature. Among the advantages reported for these peptides, their economic a ordability and easy functionalization or modulation have turned them into excellent candidates for the development of functional biomaterials. We have recently demonstrated that SPS hydrogels can be used to produce high-quality protein crystals, improve their properties, or incorporate relevant materials within the crystals. In this work, we prove that hydrogels based on methionine and tyrosine are also good candidates for growing high-quality crystals of the three model proteins: lysozyme, glucose isomerase, and thaumatin.This study was supported by projects BIO2016-74875-P and FIS2017-85954-R (Ministerio de Economía, Industria y Competitividad, MINECO, and Agencia Estatal de Investigación, AEI, Spain, cofunded by Fondo Europeo de Desarrollo Regional, FEDER, European Union)

Disease-modifying treatments for patients with multiple sclerosis in Spain

[spa] La esclerosis múltiple es una enfermedad desmielinizante crónica del sistema nervioso central y discapacitante a largo plazo. Existen diferentes tratamientos modificadores de la enfermedad. Estos pacientes, a pesar de ser generalmente jóvenes, tienen una elevada comorbilidad y riesgo de polimedicación por su compleja sintomatología y discapacidad. Objetivo principal: determinar el tipo de tratamiento modificador de la enfermedad en los pacientes atendidos en servicios de farmacia de hospitales españoles. Objetivos secundarios: Conocer los tratamientos concomitantes, determinar la prevalencia de la polifarmacia, identificar la prevalencia de interacciones y analizar la complejidad farmacoterapéutica. Método: estudio observacional, transversal y multicéntrico. Se incluyeron todos los pacientes con diagnóstico de esclerosis múltiple y tratamiento modificador de la enfermedad activo a los que se atendió en las consultas de pacientes externos o en los hospitales de día durante la segunda semana de febrero 2021. Se recogieron: el tratamiento modificador, las comorbilidades y los tratamientos concomitantes para determinar el patrón de multimorbilidad, polifarmacia, complejidad farmacoterapéutica (Medication Regimen Complexity Index) e interacciones medicamentosas. Resultados: se incluyeron 1.407 pacientes de 57 centros de 15 Comunidades Autónomas. La forma de presentación de la enfermedad más frecuente fue la forma remitente recurrente (89,3%). El tratamiento modificador de la enfermedad más prescrito fue dimetilfumarato (19,1%), seguido de teriflunomida (14,0%). De los tratamientos modificadores parenterales, los 2 más prescritos fueron el acetato de glatiramero y el natalizumab con un 11,1 y 10,8% respectivamente. El 24,7% de los pacientes tenían una comorbilidad y el 39,8% al menos 2 comorbilidades. El 13,3% pertenecía al menos a uno de los patrones definidos de multimorbilidad y el 16,5% pertenecían a 2 o más patrones. Los tratamientos concomitantes prescritos fueron los psicofármacos (35,5%), los antiepilépticos (13,9%) y los antihipertensivos y fármacos para enfermedades cardiovasculares (12,4%). La presencia de la polifarmacia fue del 32,7% y de la polifarmacia extrema el 8,1%. La prevalencia de interacciones fue del 14,8%. La mediana de complejidad farmacoterapéutica fue de 8,0 (IQR: 3,3 – 15,0). Conclusiones: se ha descrito el tratamiento modificador de la enfermedad de los pacientes con esclerosis múltiple atendidos en los servicios de farmacia españoles y se ha caracterizado los tratamientos concomitantes, la prevalencia de polifarmacia, las interacciones, y su complejidad farmacoterapéutica[eng] Multiple sclerosis is a chronic demyelinating disease of the central nervous system and long-term disabling. Different disease-modifying treatments are available. These patients, despite being generally young, have high comorbidity and risk of polymedication due to their complex symptomatology and disability. Objective primary: To determine the type of disease-modifying treatment in patients seen in Spanish hospital pharmacy departments. Secondary objectives: To determine concomitant treatments, determine the prevalence of polypharmacy, identify the prevalence of interactions and analyse pharmacotherapeutic complexity. Method: Observational, cross-sectional, multicentre study. All patients with a diagnosis of multiple sclerosis and active disease-modifying treatment who were seen in outpatient clinics or day hospitals during the second week of February 2021 were included. Modifying treatment, comorbidities and concomitant treatments were collected to determine multimorbidity pattern, polypharmacy, pharmacotherapeutic complexity (Medication Regimen Complexity Index) and drug-drug interactions. Results: 1,407 patients from 57 centres in 15 autonomous communities were included. The most frequent form of disease presentation was the relapsing remitting form (89.3%). The most prescribed disease-modifying treat-ment was dimethyl fumarate (19.1%), followed by teriflunomide (14.0%). Of the parenteral disease-modifying treatments, the two most prescribed were glatiramer acetate and natalizumab with 11.1% and 10.8%. 24.7% of the patients had one comorbidity and 39.8% had at least 2 comorbidities. 13.3% belonged to at least one of the de-fined patterns of multimorbidity and 16.5% belonged to 2 or more patterns. The concomitant treatments pre-scribed were psychotropic drugs (35.5%); antiepileptic drugs (13.9%) and antihypertensive drugs and drugs for cardiovascular pathologies (12.4%). The presence of polypharmacy was 32.7% and extreme polypharmacy 8.1%. The prevalence of interactions was 14.8%. Median pharmacotherapeutic complexity was 8.0 (IQR: 3.3 - 15.0). Conclusions: We have described the disease-modifying treatment of patients with multiple sclerosis seen in Spanish pharmacy services and characterised concomitant treatments, the prevalence of polypharmacy, interac-tions, and their complexity

Surface properties of europium-containing phosphate nanoparticles as candidates for bioimaging application

XLVII National meeting of the Physical Chemistry Division of the Italian Chemistry Society. Rome, July 1-4 201

Pilot studies of surface features of europium containing phosphate nanoparticles as candidates for bioimaging applications

6th International Conference Nanobiophysics: fundamental and applied aspects, Kyiv, Ukraine, October 1-4, 2019Horizon 2020, H2020-MSCA-RISE-2015, 690853 (2016-2019), >The influence of asymmetry and curvature of the cell membrane on the functioning of membrane proteins and transport of therapeutic compounds>; - NATO SPS 985291 (2017-2019), “A novel method for the detection of biohazards” (985291 SPS); - Sensor project 11/1 2019: (2018-2022), “Development of 2Dmaterials and >smart> sensors for medical and biological purposes”

Top-Down Preparation of Nanoquartz for Toxicological Investigations

Occupational exposure to quartz dust is associated with fatal diseases. Quartz dusts generated by mechanical fracturing are characterized by a broad range of micrometric to nanometric particles. The contribution of this nanometric fraction to the overall toxicity of quartz is still largely unexplored, primarily because of the strong electrostatic adhesion forces that prevent isolation of the nanofraction. Furthermore, fractured silica dust exhibits special surface features, namely nearly free silanols (NFS), which impart a membranolytic activity to quartz. Nanoquartz can be synthetized via bottom-up methods, but the surface chemistry of such crystals strongly differs from that of nanoparticles resulting from fracturing. Here, we report a top-down milling procedure to obtain a nanometric quartz that shares the key surface properties relevant to toxicity with fractured quartz. The ball milling was optimized by coupling the dry and wet milling steps, using water as a dispersing agent, and varying the milling times and rotational speeds. Nanoquartz with a strong tendency to form submicrometric agglomerates was obtained. The deagglomeration with surfactants or simulated body fluids was negligible. Partial lattice amorphization and a bimodal crystallite domain size were observed. A moderate membranolytic activity, which correlated with the number of NFS, signaled coherence with the previous toxicological data. A membranolytic nanoquartz for toxicological investigations was obtained