A fluorogenic, peptide-based probe for the detection of Cathepsin D in macrophages

Supplementary information The online version contains supplementary material available at https://doi.org/10.1038/s42004-023-01035-9Cathepsin D is a protease that is an effector in the immune response of macrophages, yet to date, only a limited number of probes have been developed for its detection. Herein, we report a water soluble, highly sensitive, pH insensitive fluorescent probe for the detection of Cathepsin D activity that provides a strong OFF/ON signal upon activation and with bright emission at 515 nm. The probe was synthesised using a combination of solid and solution-phase chemistries, with probe optimisation to increase its water solubility and activation kinetics by addition of a long PEG chain (5 kDa) at the C-terminus. A BODIPY fluorophore allowed detection of Cathepsin D across a wide pH range, important as the protease is active both at the low pH found in lysosomes and also in higher pH phagolysosomes, and in the cytosol. The probe was successfully used to detect Cathepsin D activity in macrophages challenged by exposure to bacteria.Engineering and Physical Sciences Research Council (EPSRC, UK) for Interdisciplinary Research Collaboration grants EP/R005257/1Medical Research Council SHIELD consortium grant MR/N02995X/

Moving into the red – a near infra-red optical probe for analysis of human neutrophil elastase in activated neutrophils and neutrophil extracellular traps

Neutrophils are the first immune cells recruited for defence against invading pathogens; however, their dysregulated activation and subsequent release of the enzyme human neutrophil elastase is associated with several, inflammation-based, diseases. Herein, we describe a FRET-based, tri-branched (one quencher, three fluorophores) near infrared probe that provides an intense OFF/ON amplified fluorescence signal for specific detection of human neutrophil elastase. The probe allowed selective detection of activated neutrophils and labelling of neutrophil extracellular traps. A tri-branched, FRET-based probe for the detection of hNE was synthesised with emission in the NIR region of the spectrum, where endogenous biomolecules have decreased absorbance, and minimal autofluorescenceUK Research & Innovation (UKRI) Engineering & Physical Sciences Research Council (EPSRC) EP/R005257/1UK Research & Innovation (UKRI) Medical Research Council UK (MRC) MR/N02995X/

Dendrimers as Innovative Radiopharmaceuticals in Cancer Radionanotherapy

Radiotherapy is one of the most commonly used cancer treatments, with an estimate of 40% success that could be improved further if more efficient targeting and retention of radiation at the tumor site were achieved. This review focuses on the use of dendrimers in radionanotherapy, an emerging technology aimed to improve the efficiency of radiotherapy by implementing nanovectorization, an already established praxis in drug delivery and diagnosis. The labeling of dendrimers with radionuclides also aims to reduce the dose of radiolabeled materials and, hence, their toxicity and tumor resistance. Examples of radiolabeled dendrimers with alpha, beta, and Auger electron emitters are commented, along with the use of dendrimers in boron neutron capture therapy (BNCT). The conjugation of radiolabeled dendrimers to monoclonal antibodies for a more efficient targeting and the application of dendrimers in gene delivery radiotherapy are also coveredThis work was financially supported by the Spanish Government (CTQ2015-69021-R, CTQ2012-34790) and the Xunta de Galicia (GRC2014/040) and by the “Institut National de la Santé et de la Recherche Médicale” (INSERM), by the “Axe Vectorisation and Radiothérapies” and the “Réseau Gliome Grand Ouest” (ReGGO) of the“Cancéropôle Grand-Ouest”. The coauthors of this manuscript are also members of the LabEx IRON “Innovative Radiopharmaceuticals in Oncologyand Neurology” as part of the french government program “Investissements d’Avenir”. F.L. thanks the European Commission, Education, Audiovisual and Cultural Executive Agency (EACEA) for an Erasmus Mundus Grant under the NanoFar Joint Doctoral ProgramS

Peripheral Functionalization of Dendrimers Regulates Internalization and Intracellular Trafficking in Living Cells

GATG (gallic acid-triethylene glycol) dendrimers represent appealing nanostructures for biomedical applications. The incorporation of specific ligands and targeting and imaging agents on their surface has resulted in promising tools in diagnosis and drug delivery. With the aim to further explore the versatility of GATG dendrimers in the biomedical field, in this work we study the effect of peripheral substitution on their uptake and intracellular trafficking in living cells. To this end, peripheral groups with different physicochemical properties and biological relevance have been installed on the surface of GATG dendrimers, and their interactions, uptake efficacy, and specificity for certain cell populations studied by confocal microscopy. Finally, this information was used to design a pH-sensitive drug delivery system for the selective release of cargo molecules inside cells after lysosomal localization. These results along with the easy functionalization and modular architecture of GATG dendrimers reveal these systems as promising nanotools in biomedicineThis work was financially supported by the Spanish MICINN (CTQ2009-10963 and CTQ2009-14146-C02-02) and the Xunta de Galicia (10CSA209021PR and CN2011/037). M.F.-V. thanks the Spanish Ministry of Education for a FPU fellowshipS

Evaluación y mejora de la calidad del proceso farmacoterapéutico en un hospital terciario

Objetivo: Mejorar la calidad del proceso farmacoterapéutico mediante la determinación de indicadores de seguridad (errores de medicación) y de eficiencia (tiempos de demora). Material y Métodos: Estudio observacional y prospectivo de junio 2011 a junio 2014 realizado con pacientes que requieren al menos 4 medicamentos en su tratamiento. Los errores de medicación (EM) se identificaron mediante la revisión y la observación directa de cada fase del proceso farmacoterapéutico evaluada. Se obtuvo el valor de los indicadores de seguridad como el porcentaje de EM respecto a las oportunidades de error en cada fase y se comparó con el valor seleccionado como estándar de referencia. Se analizó la relación entre EM por fase y las variables de estudio recogidas. Los indicadores de eficiencia se definieron a través de los tiempos de demora de la prescripción médica y de la validación farmacéutica. Se evalúo el tipo de EM, la gravedad y el riesgo de los mismos. Además en las fases del proceso farmacoterapéutico analizadas se identificaron las causas de los EM y se propusieron diferentes acciones de mejora. Resultados: Se revisaron 516 tratamientos, 4.630 medicamentos, 6.483 dosis preparadas y 3.518 dosis administradas. Del total de 516 pacientes, en 236 pacientes se detectó algún EM, un 45,7%. Se detectaron un total de 379 EM (0,73 EM/paciente). Los indicadores de calidad por fase frente a su valor estándar de referencia fueron: 6,8% vs 2% para la omisión del registro de alergia, 2,1% vs 2% para la prescripción, 0,5% vs 0,5% para la validación, 2,5% vs 4% para la preparación y 3,7% vs 4% para la administración. La proporción de EM de prescripción fue mayor en las áreas quirúrgicas que en las médicas, sin embargo no se encontró relación con el número de médicos prescriptores ni con el número de medicamentos. No hubo relación entre la proporción de EM en la fase de validación y el número de medicamentos prescritos. Sí se relacionó la proporción de EM en la preparación con el número de medicamentos preparados. La proporción de EM en la fase de administración fue mayor en las áreas quirúrgicas que en las médicas, sin embargo no se relacionó con el número de medicamentos administrados. La distribución porcentual por fase de los 379 EM detectados fue: 34,3% administración, 25,9% prescripción, 24,3% preparación, 9,2% validación y 6,3% omisión del registro de alergia. Los EM más frecuentes fueron el método de administración (19%), medicamento omitido (13%), intercambio terapéutico (10%) medicamento erróneo (10%) y la omisión del registro de alergia en el programa de prescripción electrónica del paciente (9%). Las principales causas de EM se debieron a incumplimientos de normas y protocolos de trabajo, el descuido y la falta de destreza en la utilización del programa de prescripción electrónica. La gravedad de más de la mitad de los EM fue de categoría B: el error se produjo pero no llegó al paciente. Asimismo, la gravedad en el 45% de los casos fue de categoría C: el error se produjo, llegó al paciente pero no produjo daño. Un 17% de los EM se consideraron riesgo grave. Los fármacos implicados fueron los antibióticos, antiulcerosos, antiinflamatorios no esteroideos (AINE), antihipertensivo y corticoides. El tiempo de demora de la prescripción médica mostró un valor medio de -41,9 minutos. El tiempo de demora de la validación farmacéutica mostró un valor medio de 50,5 minutos tras la prescripción médica. Entre las acciones de mejora propuestas el desarrollo de acciones de formación continuada dirigida a los profesionales, la actualización de la guía de intercambio terapéutico y de la guía farmacoterapéutica del hospital, el desarrollo de un módulo intercambio terapéutico para incluir en el sistema de prescripción electrónica y la incorporación de tecnología fueron las más importantes. Conclusiones: Los indicadores de seguridad establecidos evidencian una mejora de la calidad del proceso farmacoterapéutico durante el periodo de desarrollo del estudio. La actualización de la guía de intercambio terapéutico y de la guía farmacoterapéutica del hospital, la difusión de notas informativas y la formación de los profesionales en temas de seguridad en el uso del medicamento han sido las mejoras incorporadas durante el periodo de estudio. Por otra parte, para mejorar los indicadores de eficiencia se debe establecer un compromiso compartido entre los profesionales implicados y el equipo directivo del hospital

PEG-dendritic block copolymers for biomedical applications

The incorporation of poly(ethylene glycol) (PEG) chains at the focal point of dendrimers results in customizable platforms where the careful selection of the PEG length, the nature of the peripheral groups, and the structure and generation of the dendritic block entail materials for specific applications in the biomedical field. In this focus article, the synthesis, properties, and biomedical applications of PEG-dendritic block copolymers are discussed with examples in drug and gene delivery, tissue repair, and diagnosisThis work was financially supported by the Spanish MICINN (CTQ2009-10963 and CTQ2009-14146-C02-02) and the Xunta de Galicia (10CSA209021PR and CN2011/037).S

Chitosan hydrophobic domains are favoured at low degree of acetylation and molecular weight

The aggregation of chitosan (CS) has been studied as a function of concentration, degree of acetylation (DA), and degree of polymerization (DP) by means of pyrene fluorescence and rheology. Fluorescence experiments show that aggregation of CS involves hydrophobic domains (HD) which are more favoured as lower the DA and DP. Consistent with these results, the viscosity of CS solutions decreases continuously on increasing DA, in the whole range of DP. These results, which rule out the participation of the acetyl groups in the HD, have been interpreted by the theory of hydrophobic polyelectrolytes in terms of the electrostatic energy of the aggregatesThis work was financially supported by the Spanish Government (CTQ2009-10963 and CTQ2009-14146-C02-02) and the Xunta de Galicia (10CSA209021PR and CN2011/037)S

Stepwise Filtering of the Internal Layers of Dendrimers by Transverse-Relaxation-Edited NMR

The characteristic distribution of transverse relaxation times (T2) within dendrimers (shorter values at the core than the periphery) can be exploited in T2-edited 1D and 2D NMR experiments for the stepwise filtering of internal nuclei according to their topology within the dendritic structure. The resulting filtered spectra, which can be conceived as corresponding to virtual hollow dendrimers, benefit from reduced signal overlap, thus facilitating signal assignment and characterization. The generality of the method as a powerful tool in structural and end-group analysis has been confirmed with various dendritic families and nuclei (1H, 13C, 31P)This work was financially supported by the Spanish Government (CTQ2009-10963, CTQ2012-34790, CTQ2009-14146-C02-02, CTQ2012-33436) and the Xunta de Galicia (10CSA209021PR and CN2011/037). L.F.P. thanks the Portuguese Foundation for Science and Technology (FCT MCTES) for a Ph.D. grant (SFRH/BD/37341/2007)S

Disclosing an NMR-Invisible Fraction in Chitosan and PEGylated Copolymers and Its Role on the Determination of Degrees of Substitution

An unexpected 1H NMR invisible fraction (IF) for chitosan (CS) and CS-g-PEG is reported. The presence of this IF is remarkable considering that solution NMR is recognized as the method of choice for studying structural modifications in CS, including the degrees of acetylation (DA) and substitution (DS). In spite of IF figures as high as 50%, this IF does not interfere in the correct determination of the DA by 1H NMR, pointing to a homogeneous distribution of acetyl groups along the visible and invisible fractions. Quite in contrast, the IF negatively biases the determination of the DS in CS-g-PEG, with relative errors as high as 150% in a broad range of temperatures, pH values, and concentrations. This fact raises concerns about the accuracy of previously reported DS data for CS-g-PEG and many other CS copolymers. Efficient user-friendly conditions have been developed for the correct determination of the DS of CS-g-PEG by depolymerization by nitrous acidThis work was financially supported by the Spanish Government (CTQ2009-10963, CTQ2012-34790, CTQ2009-14146-C02-02, and CTQ2012-33436) and the Xunta de Galicia (10CSA209021PR and CN2011/037)S

In situ nanofabrication of hybrid PEG-dendritic–inorganic nanoparticles and preliminary evaluation of their biocompatibility

An in situ template fabrication of inorganic nanoparticles using carboxylated PEG-dendritic block copolymers of the GATG family is described as a function of the dendritic block generation, the metal (Au, CdSe) and metal molar ratio. The biocompatibility of the generated nanoparticles analysed in terms of their aggregation in physiological media, cytotoxicity and uptake by macrophages relates to the PEG density of the surface of the hybridsC.S.E. and A.G.-F. thank to the European Commission BIOCAPS (316265, FP7/REGPOT-2012-2013.1) and Xunta de Galicia (Agrupamento INBIOMED and Grupo con potencial crecimiento). A.S.-H. and E.F.-M. thank the Spanish Government (CTQ2012-34790) and the Xunta de Galicia (CN2011/037)S