60 research outputs found

    Novel systems for bioimaging and photodynamic therapy: BODIPY dyes and silica-based nanocarriers.

    Get PDF
    235 p.En este trabajo se han propuesto nuevos colorantes basados principalmente en la estructura del cromóforo BODIPY, así como nuevos nanosistemas híbridos fotoactivos para su potencial implementación en el campo biomedicina, en particular para bioimagen y terapia fotodinámica del cáncer.Primero, el desarrollo de nuevos biomarcadores fluorescentes se basó en la modificación del cromóforo BODIPY para mejorar su solubiliad en medios acuosos y su selectividad hacia orgánulos específicos de la célula i.e. mitocondria. Para ellos, se añadieron grupos hidrofílicos y biomoleculas especificas, respectivamente. Posteriormente, se estudió la funcionalización del cromóforo BODIPY con el objetivo de lograr fotosensibilizadores con alta producción de oxigeno singlete por un lado mediante la introducción de átomos halogenados y además sistemas ¿-conjugados que desplazan la absorción hacia la región roja dentro de la ventana clínica, o por otro lado anclando grupos dadores de electrones que activen un estado de transferencia de carga intramolecular capaz de modular la capacidad fluorescente junto con la generación de oxígeno singlete, ideal para aplicaciones teranosticas.Además, se sintetizaron tres tipos de nanopartículas esféricas de sílice (no porosas, mesoporosas y ormosil) de entorno a 50 nm de tamaño, que junto con una nanoarcilla sintética (laponita) de unos 100 nm, se utilizaron como trasportadores de colorantes: fluoroforos (principalmente ocluidos en el core) o fotosensibilizadores (unidos covalentemente en la superficie externa). Estos nanosistemas se funcionalizaron además con polietilen glicol y ácido fólico para mejorar su estabilidad en agua y su selectividad hacia células tumorales

    Photosensitizer-Mesoporous Silica Nanoparticles Combination for Enhanced Photodynamic Therapy

    Get PDF
    Mesoporous silica nanoparticles (MSNs) are widely known for their versatile applications. One of the most extended is as drug delivery systems for the treatment of cancer and other diseases. This review compiles the most representative examples in the last years of functionalized MSNs as photosensitizer carriers for photodynamic therapy (PDT) against cancer. Several commercially available photosensitizers (PSs) demonstrated poor solubility in an aqueous medium and insufficient selectivity for cancer tissues. The tumor specificity of PSs is a key factor for enhancing the PDT effect and at the same time reducing side effects. The use of nanoparticles and particularly MSNs, in which PS is covalently anchored or physically embedded, can overcome these limitations. For that, PS-MSNs can be externally decorated with compounds of interest in order to act as an active target for certain cancer cells, demonstrating enhanced phototoxicity in vitro and in vivo. The objective of this review is to collect and compare different nanosystems based on PS-MSNs pointing out their advantages in PDT against diverse types of cancers.We gratefully acknowledge financial support from MCIN/AEI/10.13039/501100011033 (project PID2020-114347RB-C32), and Gobierno Vasco-Eusko Jaurlaritza (project IT1639-22). R.P.-M. thanks UPV/EHU, MIU and NGEU for their postdoctoral contract (MARSA21/71)

    Functionalized Fluorescent Silica Nanoparticles for Bioimaging of Cancer Cells

    Get PDF
    Functionalized fluorescent silica nanoparticles were designed and synthesized to selectively target cancer cells for bioimaging analysis. The synthesis method and characterization of functionalized fluorescent silica nanoparticles (50–60 nm), as well as internalization and subcellular localization in HeLa cells is reported here. The dye, rhodamine 101 (R101) was physically embedded during the sol–gel synthesis. The dye loading was optimized by varying the synthesis conditions (temperature and dye concentration added to the gel) and by the use of different organotriethoxysilanes as a second silica precursor. Additionally, R101, was also covalently bound to the functionalized external surface of the silica nanoparticles. The quantum yields of the dye-doped silica nanoparticles range from 0.25 to 0.50 and demonstrated an enhanced brightness of 230–260 fold respect to the free dye in solution. The shell of the nanoparticles was further decorated with PEG of 2000 Da and folic acid (FA) to ensure good stability in water and to enhance selectivity to cancer cells, respectively. In vitro assays with HeLa cells showed that fluorescent nanoparticles were internalized by cells accumulating exclusively into lysosomes. Quantitative analysis showed a significantly higher accumulation of FA functionalized fluorescent silica nanoparticles compared to nanoparticles without FA, proving that the former may represent good candidates for targeting cancer cells.This research was funded by the Basque Government, grant numbers IT912-16 and IT-1302-19; Ministry of Economy and Competitiveness (MINECO), grant numbers MAT2017-83856-C3-3-P and CTM2016-81130-R; and the University of the Basque Country (UPV/EHU), grant number COLAB19/01

    Red haloBODIPYs as theragnostic agents: The role of the substitution at meso position

    Get PDF
    Three different molecular designs based on BODIPY dye have been proposed as photosensitizers (PSs) for photodynamic therapy (PDT) by the inclusion of halogen atoms (Iodine) at 2,6-positions and with extended conjugation at 3, 5-positions and varying the substitution at meso position. The synthesis is described and their main photophysical features including singlet oxygen production and triplet states were characterized by absorption and fluorescence spectroscopy (steady-state and time-correlated) and nanosecond transient absorption spectroscopy. The results were compared with the commercial Chlorin e6. The three new red-halogen-BODIPYs showed a great balance between singlet oxygen generation (Phi(Delta)>= 0.40) and fluorescence (Phi(fl)>= 0.22) for potential application on PDT, and particularly in theragnosis. In vitro experiments in HeLa cells were done to study their performance and to elucidate the best potential candidate for PDT.This research was funded by the Basque Government, grant numbers IT912-16, IT-1302-19 and IT1639-22. This work is supported by Min-isterio de Ciencia, Innovacion y Universidades-Agencia Estatal de Investigacion (MCI/AEI) , grant numbers MAT2017-83856-C3-2-P and 3-P, PID2020-114347RB-C32, PID2020-114755 GB-C32 and the Uni-versity of the Basque Country (UPV/EHU) , grant number COLAB19/01. R.P.M. thanks UPV/EHU for postdoctoral felowship (DOCREC 20/55) . Open Access funding is provided by University of Basque Country

    Measuring the Burden of Hospitalization in Patients with Parkinson´s Disease in Spain

    Get PDF
    Introduction: This epidemiological survey estimates the hospitalization burden related to Parkinson´s Disease in Spain. Methods: This observational retrospective survey was performed by reviewing data from the National Surveillance System for Hospital Data, which includes more than 98% of Spanish hospitals. All hospitalizations of patients with Parkinson´s disease that were reported from 1997-2012 were analyzed. Codes were selected using the 9th International Classification of Diseases: ICD-9-CM: 332.0. Results: A total of 438,513 hospital discharges of patients with Parkinson´s Disease were reported during the study period. The annual hospitalization rate was 64.2 cases per 100,000. The average length of hospital stay was 10 days. The trend for the annual hospitalization rate differed significantly depending on whether Parkinson´s disease was the main cause of hospitalization (n = 23,086, 1.14% annual increase) or was not the main cause of hospitalization (n = 415,427, 15.37% annual increase). The overall case-fatality rate among hospitalized patients was 10%. The case fatality rate among patient´s hospitalized with Parkinson´s disease as the main cause of hospitalization was 2.5%. The hospitalization rate and case-fatality rate significantly increased with age. The primary causes of hospitalization when Parkinson´s disease was not coded as the main cause of hospitalization were as follows: respiratory system diseases (24%), circulatory system diseases (19%), injuries and poisoning, including fractures (12%), diseases of the digestive system (10%) and neoplasms (5%). The annual average cost for National Health Care System was € 120 M, with a mean hospitalization cost of €4,378. Conclusions: Parkinson´s disease poses a significant health threat in Spain, particularly in the elderly. While hospitalizations due to Parkinson´s Disease are relatively stable over time, the number of patients presenting with Parkinson´s disease as an important comorbidity has increased dramatically. Medical staff must be specifically trained to treat the particular needs of hospitalized patients suffering from Parkinson´s disease as an important comorbidity.Funding sources for study: The cathedra “Evaluación de Resultados en Salud. Rey Juan Carlos University” is sponsored by Abbvie.S

    Functionalization of photosensitized silica nanoparticles for advanced photodynamic therapy of cancer

    Get PDF
    BODIPY dyes have recently attracted attention as potential photosensitizers. In this work, commercial and novel photosensitizers (PSs) based on BODIPY chromophores (haloBODIPYs and orthogonal dimers strategically designed with intense bands in the blue, green or red region of the visible spectra and high singlet oxygen production) were covalently linked to mesoporous silica nanoparticles (MSNs) further functionalized with PEG and folic acid (FA). MSNs approximately 50 nm in size with different functional groups were synthesized to allow multiple alternatives of PS-PEG-FA decoration of their external surface. Different combinations varying the type of PS (commercial Rose Bengal, Thionine and Chlorine e6 or custom-made BODIPY-based), the linkage design, and the length of PEG are detailed. All the nanosystems were physicochemically characterized (morphology, diameter, size distribution and PS loaded amount) and photophysically studied (absorption capacity, fluorescence efficiency, and singlet oxygen production) in suspension. For the most promising PS-PEG-FA silica nanoplatforms, the biocompatibility in dark conditions and the phototoxicity under suitable irradiation wavelengths (blue, green, or red) at regulated light doses (10–15 J/cm2) were compared with PSs free in solution in HeLa cells in vitro

    Red haloBODIPYs as theragnostic agents: The role of the substitution at meso position

    Get PDF
    Three different molecular designs based on BODIPY dye have been proposed as photosensitizers (PSs) for photodynamic therapy (PDT) by the inclusion of halogen atoms (Iodine) at 2,6-positions and with extended conjugation at 3, 5-positions and varying the substitution at meso position. The synthesis is described and their main photophysical features including singlet oxygen production and triplet states were characterized by absorption and fluorescence spectroscopy (steady-state and time-correlated) and nanosecond transient absorption spectroscopy. The results were compared with the commercial Chlorin e6. The three new red-halogen-BODIPYs showed a great balance between singlet oxygen generation (ΦΔ≥0.40) and fluorescence (Φfl≥0.22) for potential application on PDT, and particularly in theragnosis. In vitro experiments in HeLa cells were done to study their performance and to elucidate the best potential candidate for PDT

    Predictive Power of the "Trigger Tool" for the detection of adverse events in general surgery: a multicenter observational validation study

    Get PDF
    Background In spite of the global implementation of standardized surgical safety checklists and evidence-based practices, general surgery remains associated with a high residual risk of preventable perioperative complications and adverse events. This study was designed to validate the hypothesis that a new “Trigger Tool” represents a sensitive predictor of adverse events in general surgery. Methods An observational multicenter validation study was performed among 31 hospitals in Spain. The previously described “Trigger Tool” based on 40 specific triggers was applied to validate the predictive power of predicting adverse events in the perioperative care of surgical patients. A prediction model was used by means of a binary logistic regression analysis. Results The prevalence of adverse events among a total of 1,132 surgical cases included in this study was 31.53%. The “Trigger Tool” had a sensitivity and specificity of 86.27% and 79.55% respectively for predicting these adverse events. A total of 12 selected triggers of overall 40 triggers were identified for optimizing the predictive power of the “Trigger Tool”. Conclusions The “Trigger Tool” has a high predictive capacity for predicting adverse events in surgical procedures. We recommend a revision of the original 40 triggers to 12 selected triggers to optimize the predictive power of this tool, which will have to be validated in future studies

    The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

    Get PDF
    Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

    Dolutegravir twice-daily dosing in children with HIV-associated tuberculosis: a pharmacokinetic and safety study within the open-label, multicentre, randomised, non-inferiority ODYSSEY trial

    Get PDF
    Background: Children with HIV-associated tuberculosis (TB) have few antiretroviral therapy (ART) options. We aimed to evaluate the safety and pharmacokinetics of dolutegravir twice-daily dosing in children receiving rifampicin for HIV-associated TB. Methods: We nested a two-period, fixed-order pharmacokinetic substudy within the open-label, multicentre, randomised, controlled, non-inferiority ODYSSEY trial at research centres in South Africa, Uganda, and Zimbabwe. Children (aged 4 weeks to <18 years) with HIV-associated TB who were receiving rifampicin and twice-daily dolutegravir were eligible for inclusion. We did a 12-h pharmacokinetic profile on rifampicin and twice-daily dolutegravir and a 24-h profile on once-daily dolutegravir. Geometric mean ratios for trough plasma concentration (Ctrough), area under the plasma concentration time curve from 0 h to 24 h after dosing (AUC0–24 h), and maximum plasma concentration (Cmax) were used to compare dolutegravir concentrations between substudy days. We assessed rifampicin Cmax on the first substudy day. All children within ODYSSEY with HIV-associated TB who received rifampicin and twice-daily dolutegravir were included in the safety analysis. We described adverse events reported from starting twice-daily dolutegravir to 30 days after returning to once-daily dolutegravir. This trial is registered with ClinicalTrials.gov (NCT02259127), EudraCT (2014–002632-14), and the ISRCTN registry (ISRCTN91737921). Findings: Between Sept 20, 2016, and June 28, 2021, 37 children with HIV-associated TB (median age 11·9 years [range 0·4–17·6], 19 [51%] were female and 18 [49%] were male, 36 [97%] in Africa and one [3%] in Thailand) received rifampicin with twice-daily dolutegravir and were included in the safety analysis. 20 (54%) of 37 children enrolled in the pharmacokinetic substudy, 14 of whom contributed at least one evaluable pharmacokinetic curve for dolutegravir, including 12 who had within-participant comparisons. Geometric mean ratios for rifampicin and twice-daily dolutegravir versus once-daily dolutegravir were 1·51 (90% CI 1·08–2·11) for Ctrough, 1·23 (0·99–1·53) for AUC0–24 h, and 0·94 (0·76–1·16) for Cmax. Individual dolutegravir Ctrough concentrations were higher than the 90% effective concentration (ie, 0·32 mg/L) in all children receiving rifampicin and twice-daily dolutegravir. Of 18 children with evaluable rifampicin concentrations, 15 (83%) had a Cmax of less than the optimal target concentration of 8 mg/L. Rifampicin geometric mean Cmax was 5·1 mg/L (coefficient of variation 71%). During a median follow-up of 31 weeks (IQR 30–40), 15 grade 3 or higher adverse events occurred among 11 (30%) of 37 children, ten serious adverse events occurred among eight (22%) children, including two deaths (one tuberculosis-related death, one death due to traumatic injury); no adverse events, including deaths, were considered related to dolutegravir. Interpretation: Twice-daily dolutegravir was shown to be safe and sufficient to overcome the rifampicin enzyme-inducing effect in children, and could provide a practical ART option for children with HIV-associated TB
    corecore