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1.
Artículo en Inglés | MEDLINE | ID: mdl-39058909

RESUMEN

PURPOSE: To determine the rate of genetic testing for familial hyperaldosteronism (FH) in the SPAIN-ALDO Registry and to describe the clinical characteristics of patients with FH. In addition, a literature review of reports of FH cases was performed. METHODS: A retrospective multicenter study of primary aldosteronism (PA) in patients followed in 35 Spanish tertiary hospitals (SPAIN-ALDO Registry). RESULTS: Twenty-five of the 855 patients (3%) with PA included in the registry underwent genetic testing for FH, with complete results available in only 24 patients. However, we found that there were 57 patients who met the criteria for performing a genetic study of PA. Only 8 out of these 57 patients were genetically tested (14.0%), while the reasons to perform a genetic study in the remaining 9 genetically studied cases were quite heterogeneous. A positive result for FH was found only in one case for FH type III (KCNJ5 pathogenic variant). A systematic review of the literature was performed and identified a total of 25 articles reporting 246 patients with FH type I; 12 articles reporting 72 patients with FH type II; 14 articles reporting 29 cases of FH type III and 3 articles reporting 12 patients with FH type IV. CONCLUSION: The genetic study of familial hyperaldosteronism is often scarce in real-world clinical practice, as 86% of patients with criteria to undergo genetic study were not evaluated in our cohort. Nevertheless, FH is an uncommon cause of PA, representing only 0.2% of cases in the SPAIN-ALDO Registry, although its prevalence may be as high as 4% among suspected cases might be studied.

2.
Open Res Eur ; 3: 60, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37645495

RESUMEN

Background: The conservation of the built masonry heritage requires a comprehensive understanding of its geometrical, structural, and material characteristics. Non-destructive techniques are a preferred approach to survey historical buildings, given the cultural value of their fabric. However, currently available techniques are typically operated manually, consuming much time at operational and processing level and thus hindering their use for the on-site inspection of heritage structures. Methods: A novel automated sonic tomography system was designed and built to inspect and obtain information about the inner structure and damage of historic masonry walls. The system consists of a hitting device mounted on a frame that can be placed adjacent to the wall under analysis. The hitting device can move along the surface within the frame area in X, Y and Z directions, generating the sonic wave. The receiving system is a scanning laser vibrometer, able to measure from the distance the displacement of a focused point over time, recording the wave when it reaches the opposite surface. Results: Six stone masonry walls with different interior geometries were constructed at the laboratory by a professional stonemason. The construction of the walls was carefully documented, including the generation of detailed photogrammetric models of each single stone. The system was applied to survey the six masonry walls. Since the inner morphology of the walls is known, the resulting tomographic images could be compared with the ground truth. Conclusions: Automating the inspection allowed to collect thousands of data in a few hours. New software was also developed to automate the processing of the data. Results are expected to highlight the potential of tomography to obtain quantitative information about the interior of heritage structures, while providing new tools that make the implementation of the technique more practical for professionals. Data, software and models have been made publicly available.

3.
Cancers (Basel) ; 14(14)2022 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-35884536

RESUMEN

The etiology of prostate cancer (PCa) remains uncertain, and the role of diet is unclear. We aimed to evaluate the role of diet, through dietary patterns, on PCa, considering tumor aggressiveness and extension. The CAPLIFE study is a population-based case-control study including a total of 428 incident PCa cases and 393 controls aged 40-80 years. Dietary information was collected through a validated food frequency questionnaire. Three dietary patterns were identified through principal component analysis: "Mediterranean," "Western," and "Unhealthy," which were categorized into tertiles according to the control group cutoff points. Tumor aggressiveness and extension was determined. Logistic regression models were used to assess the association between dietary patterns and PCa. High adherence to an unhealthy dietary pattern was associated with higher odds of PCa, ORT3vsT1 = 1.52 (95% CI 1.02-2.27), especially for cases with ISUP 1-2 and localized PCa tumors. This association was not observed with a Western or Mediterranean pattern. In conclusion, adherence to an unhealthy diet appears to be associated with higher odds of PCa, especially for cases with ISUP 1-2 and localized PCa tumors.

4.
Antibiotics (Basel) ; 11(5)2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35625285

RESUMEN

Fluoroquinolones (FQs) are a critical group of antimicrobials prescribed in urological infections as they have a broad antimicrobial spectrum of activity and a favorable tissue penetration at the site of infection. However, their clinical practice is not problem-free of treatment failure, risk of emergence of resistance, and rare but important adverse effects. Due to their critical role in clinical improvement, understanding the dose-response relation is necessary to optimize the effectiveness of FQs therapy, as it is essential to select the right antibiotic at the right dose for the right duration in urological infections. The aim of this study was to review the published literature about inter-individual variability in pharmacological processes that can be responsible for the clinical response after empiric dose for the most commonly prescribed urological FQs: ciprofloxacin, levofloxacin, and moxifloxacin. Interindividual pharmacokinetic (PK) variability, particularly in elimination, may contribute to treatment failure. Clearance related to creatinine clearance should be specifically considered for ciprofloxacin and levofloxacin. Likewise, today, undesired interregional variability in FQs antimicrobial activity against certain microorganisms exists. FQs pharmacology, patient-specific characteristics, and the identity of the local infecting organism are key factors in determining clinical outcomes in FQs use.

5.
Small ; 18(11): e2104420, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35037383

RESUMEN

Biocatalytic cascades are challenging to operate in homogeneous solution, where diffusional mass transport hinders efficient communication between the reactive components. There is great interest in developing devices to perform such transformations in confined environments, which increase the efficiency of the cascaded process by generating high local concentrations of the reactive species. Herein, a bioreactor-nanozyme assembly is introduced for the cascaded aerobic oxidation of N-hydroxy-l-arginine (NOHA) to citrulline in the presence of glucose. The reaction mimics a key step in the nitric oxide synthase oxidation of l-arginine in nature. The system consists of glucose oxidase (GOx)-loaded hemin/G-quadruplex (hemin/G4)-modified ZIF-90 metal-organic framework nanoparticles. The aerobic oxidation of glucose by GOx yields H2 O2 that fuels the hemin/G4-catalyzed oxidation of NOHA into citrulline. The process driven by the bioreactor-nanozyme system is ≈sixfold enhanced compared to the homogeneous mixture of the biocatalysts, due to its operation in the confined environment of the nanoparticles. Extension to a three-step cascade is then demonstrated using a bioreactor composed of ß-galactosidase/GOx-loaded hemin/G4-modified ZIF-90 nanoparticles activating the cascaded oxidation of NOHA to citrulline, in the presence of lactose. Moreover, the bioreactor-nanozyme hybrid is applied as a functional optical sensor of glucose, using fluorescence or chemiluminescence as readout signals.


Asunto(s)
Estructuras Metalorgánicas , Nanopartículas , Arginina , Reactores Biológicos , Hemina
6.
Rev. esp. med. prev. salud pública ; 27(3): 8-13, 2022. graf
Artículo en Español | IBECS | ID: ibc-212831

RESUMEN

Objetivo: Seleccionar las características más relevantes a la hora de predecir una infección de sitio quirúrgico en un paciente sometido a intervención de artroplastia de cadera. Método: Se ha utilizado un método de selección de características basado en Información Mutua (IM) para determinar las variables que mejor predicen la infección de sitio quirúrgico (ISQ) en una cohorte prospectiva de pacientes operados de artroplastia de cadera en el Hospital Universitario Ramón y Cajal entre los años 2010 y 2020. Resultados: La característica más importante para la predicción fue el tiempo postoperatorio (0,98 valor de IM). Todas las ISQ ocurrieron tras el primer ingreso. Conclusiones: Los resultados obtenidos ponen en valor las técnicas de aprendizaje automático para tomar medidas organizativas que reduzcan los días de estancia, y así prevenir la aparición de ISQ, disminuir los costes del proceso clínico y aumentar la seguridad del paciente.(AU)


Objective: Select the most relevant characteristics to predict a surgical site infection in a patient undergoing hip arthroplasty. Methods: Mutual information (MI) method is used to select the characteristics that better predict Surgical Site Infection (SSI) in a prospective cohort of patients who underwent hip arthroplasty between 2010 and 2020 at the Ramón y Cajal University Hospital. Results: The most important characteristic to predict SSI was postoperative time (0.98 MI score). All SSIs occurred after the first admission. Conclusion: The results obtained highlight the value of machine learning techniques to take organizational measures that reduce the days of stay, and thus prevent the appearance of SSIs, reduce the costs of the clinical process and increase patient safety.(AU)


Asunto(s)
Humanos , Infección Hospitalaria , Predicción , Artroplastia de Reemplazo de Cadera , Quirófanos , Infección de la Herida Quirúrgica , Seguridad del Paciente , Factores de Riesgo , Estudios de Cohortes , Medicina Preventiva , Salud Pública , Control de Infecciones
7.
Rev. esp. med. prev. salud pública ; 27(3): 14-20, 2022. graf
Artículo en Español | IBECS | ID: ibc-212832

RESUMEN

Objetivo: Describir la casuística de los pacientes con cultivo positivo para Enterobacterias Productoras de Carbapenemasas (EPC), la complejidad de sus patologías y el consumo de recursos hospitalarios. Método: Estudio observacional retrospectivo en pacientes con diagnóstico de infección/colonización por EPC (2013-2018) en el Hospital Universitario Fundación Alcorcón. Estudio descriptivo de los pacientes y análisis de los recursos consumidos utilizando los Grupos de Diagnóstico Relacionado y la estancia media (EM). Resultados: Se analizan 119 pacientes con edad media de 76,9 años, siendo la localización más frecuente en orina (58,8%) y la carbapenemasa más habitual en enterobacterias la OXA-48 (79,8%). La EM de estos pacientes y el peso medio (PM) fue significativamente superior al de las altas hospitalarias en este período (p<0,05). Conclusiones: Los pacientes que asocian un diagnóstico de EPC incrementan el consumo de recursos hospitalarios triplicando los días de estancia y la complejidad del proceso atendido (aumento del 50% en el PM).(AU)


Objective: Describe case-mix of patients with positive culture for Carbapenemase-Producing Enterobacteriaceae (CPE), complexity of their pathologies and hospital resources consumption. Method: Retrospective observational study in patients with diagnosis of CPE infection/colonization (2013-2018) at Alcorcon University Hospital Foundation. Patient descriptive study and resource consumption analysis using Diagnosis Related Groups (DRG ́s) and mean length of stay (LOS). Results: 119 patients were analyzed. The average age was 76.9 years, the most frequent location was urine (58.8%) and OXA-48 the most common carbapenemase in the enterobacteriaceae (79.8%). The mean LOS of these patients and the DRG relative weight was higher than the patients treated during this period (p<0.05). Conclusions: Patients with diagnosis of CPE associate a greater consumption of hospital resources tripling the LOS and increasing 50% relative weight of DRG.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Anciano , Pacientes , Control de Infecciones , Enterobacteriaceae Resistentes a los Carbapenémicos , Enterobacteriaceae , Monitoreo Epidemiológico , Grupos Diagnósticos Relacionados , Estudios Retrospectivos , Salud Pública , Medicina Preventiva
9.
Med. clín. soc ; 5(2)ago. 2021.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1386218

RESUMEN

RESUMEN La esclerodermia cutánea localizada es una enfermedad crónica del tejido conectivo, etiología desconocida, caracterizada por áreas de piel induradas. Existen varias formas. La Morfea es una enfermedad rara con incidencia de 0,3-3 casos por 100.000 habitantes / año. Más común en mujeres, proporción 4:1 mujer/hombre. Mujer, 21 años acude al Servicio de Dermatología del Hospital de Clínicas por cuadro de 3 años de evolución de mancha roja en cadera de lado derecho que luego se vuelve marrón, aparece luego otra lesión similar en muslo y rodilla derechos con misma evolución, sin desencadenante aparente ni síntomas acompañantes. Al examen físico se observa varias placas hipocrómicas algunas con bordes eritematosos, entre 2-3 cm, límites netos y bordes irregulares distribuidos en muslo derecho. Placas hipercrómicas induradas entre 1-6 cm de diámetro, límites netos, bordes regulares en cadera y muslo derechos, y brazo izquierdo. Piel difícil de plegar. Biopsia de piel compatible con Morfea. Recibe tratamiento con hidroxicloroquina, metotrexate, corticoides tópicos, vitamina A, C, E con respuesta y evolución favorable. Esclerodermia localizada aparece en adultos entre 40- 50 años, en comparación con paciente que afectó segunda década de vida. Tronco como localización más frecuente, característica de la paciente, además en miembros superiores e inferiores. Artralgias se presentan en 44% de casos, coincidentes con la paciente. Aumento del factor reumatoideo, eosinofilia, VSG guían hacia diagnóstico de Morfea en fase activa, no apreciables en el caso. Tratamiento con metotrexate como inmunosupresor es la terapéutica con evolución favorable, así como indican estudios, complementados con hidroxicloroquina y vitaminas A y E.


ABSTRACT Localized scleroderma is a chronic connective tissue disease, unknown etiology, characterized by areas of indurated skin. There are several types. It is a rare disease with an incidence of 0.3-3 cases per 100,000 inhabitants / year. More common in Caucasian women, with a 2-4:1 female/male ratio. Woman, 21 years of age goes to the Dermatology Department of the Hospital de Clínicas for the 3-year history of the red woman on the right who later turns brown, a similar lesion appears on the right leg, apparently not trigger or symptoms companions. On physical examination, several hypochromic plaques were observed, some with erythematous borders, between 2-3 cm, net boundaries and irregular borders distributed in the right thigh. Indurated hyperchromic plates between 1 and 6 cm in diameter, net boundaries, regular edges in red and right thighs, and left side. Skin difficult to fold. Skin biopsy compatible with Morphea. Treated with hydroxychloroquine, methotrexate, topical corticosteroids, vitamin A, C, E with response and favorable evolution. Localized scleroderma appears in adults between 40-50 years, in comparison with the patient who affected the second decade of life. The trunk as the most frequent location, found in the patient, also in the upper and lower limbs. Join pains are presented in 44% of cases. Increase of the rheumatoid factor, eosinophilia, VSG guide to the diagnosis of Morphea in active phase, not appreciable in the case. Treatment with methotrexate as an immunosuppressant is the appropriate therapy, as indicated by studies, supplemented with hydroxychloroquine and vitamins A and E.

10.
J Am Chem Soc ; 143(30): 11510-11519, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-34286967

RESUMEN

The covalent linkage of aptamer binding sites to nanoparticle nanozymes is introduced as a versatile method to improve the catalytic activity of nanozymes by concentrating the reaction substrates at the catalytic nanozyme core, thereby emulating the binding and catalytic active-site functions of native enzymes. The concept is exemplified with the synthesis of Cu2+ ion-functionalized carbon dots (C-dots), modified with the dopamine binding aptamer (DBA) or the tyrosinamide binding aptamer (TBA), for the catalyzed oxidation of dopamine to aminochrome by H2O2 or the oxygenation of l-tyrosinamide to the catechol product, which is subsequently oxidized to amidodopachrome, in the presence of H2O2/ascorbate mixture. Sets of structurally functionalized DBA-modified Cu2+ ion-functionalized C-dots or sets of structurally functionalized TBA-modified Cu2+ ion-functionalized C-dots are introduced as nanozymes of superior catalytic activities (aptananozymes) toward the oxidation of dopamine or the oxygenation of l-tyrosinamide, respectively. The aptananozymes reveal enhanced catalytic activities as compared to the separated catalyst and respective aptamer constituents. The catalytic functions of the aptananozymes are controlled by the structure of the aptamer units linked to the Cu2+ ion-functionalized C-dots. In addition, the aptananozyme shows chiroselective catalytic functions demonstrated by the chiroselective-catalyzed oxidation of l/d-DOPA to l/d-dopachrome. Binding studies of the substrates to the different aptananozymes and mechanistic studies associated with the catalytic transformations are discussed.


Asunto(s)
Aptámeros de Nucleótidos/química , Cobre/química , Carbono/química , Catálisis , Dopamina/química , Estructura Molecular , Oxidación-Reducción , Puntos Cuánticos/química , Tirosina/análogos & derivados , Tirosina/química
11.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670386

RESUMEN

Sequence-specific nucleic acids exhibiting selective recognition properties towards low-molecular-weight substrates and macromolecules (aptamers) find growing interest as functional biopolymers for analysis, medical applications such as imaging, drug delivery and even therapeutic agents, nanotechnology, material science and more. The present perspective article introduces a glossary of examples for diverse applications of aptamers mainly originated from our laboratory. These include the introduction of aptamer-functionalized nanomaterials such as graphene oxide, Ag nanoclusters and semiconductor quantum dots as functional hybrid nanomaterials for optical sensing of target analytes. The use of aptamer-functionalized DNA tetrahedra nanostructures for multiplex analysis and aptamer-loaded metal-organic framework nanoparticles acting as sense-and-treat are introduced. Aptamer-functionalized nano and microcarriers are presented as stimuli-responsive hybrid drug carriers for controlled and targeted drug release, including aptamer-functionalized SiO2 nanoparticles, carbon dots, metal-organic frameworks and microcapsules. A further application of aptamers involves the conjugation of aptamers to catalytic units as a means to mimic enzyme functions "nucleoapzymes". In addition, the formation and dissociation of aptamer-ligand complexes are applied to develop mechanical molecular devices and to switch nanostructures such as origami scaffolds. Finally, the article discusses future challenges in applying aptamers in material science, nanotechnology and catalysis.


Asunto(s)
Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanoestructuras/química , Nanoestructuras/uso terapéutico , Animales , Catálisis , Humanos , Plata/química , Plata/uso terapéutico
12.
J Fish Dis ; 44(7): 993-1004, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33675091

RESUMEN

Piscirickettsia salmonis is the aetiological agent of piscirickettsiosis, a bacterial disease that affects farmed salmonids, causing high mortalities and significant economic losses in the Chilean salmon farm industry. Given the Chilean native fish species Patagonian blenny, Eleginops maclovinus, lives in the vicinity of salmon farms, it is relevant to clarify the epidemiological role that this species could play in the transmission and/or dissemination of this pathogen. This study aimed to evaluate the bidirectional transmission of P. salmonis between the Patagonian blenny and Oncorhynchus mykiss (rainbow trout), via a cohabitation challenge model. The results of this study demonstrated the transmission of the bacteria from Patagonian blennies to rainbow trout, considering the specific mortality in cohabitant rainbow trout, reaching 46%: the necropsy of these specimens, evidencing the characteristic pathological lesions of the disease and the positive results of the qPCR analysis for P. salmonis, in the same individuals. In contrast, no mortalities of Patagonian blenny specimens were recorded in the challenged experimental groups. This study is the first report showing the horizontal transmission of P. salmonis from a native non-salmonid species, such as the Patagonian blenny, to a salmonid species, generating the disease and specific mortality in rainbow trout, using a cohabitation challenge.


Asunto(s)
Infecciones Bacterianas/veterinaria , Enfermedades de los Peces/microbiología , Oncorhynchus mykiss/microbiología , Perciformes/microbiología , Piscirickettsia , Animales , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/mortalidad , Derrame de Bacterias , Enfermedades de los Peces/transmisión , Factores de Tiempo
13.
Chem Soc Rev ; 50(7): 4541-4563, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33625421

RESUMEN

Stimuli-responsive metal-organic framework nanoparticles, NMOFs, provide a versatile platform for the controlled release of drugs and biomedical applications. The porous structure of NMOFs, their biocompatibility, low toxicity, and efficient permeability turn the NMOFs into ideal carriers for therapeutic applications. Two general methods to gate the drug-loaded NMOFs and to release the loads were developed: by one method, the loaded NMOFs are coated or surface-modified with stimuli-responsive gates being unlocked in the presence of appropriate chemical (e.g., ions or reducing agents), physical (e.g., light or heat), or biomarker (e.g., miRNA or ATP) triggers. By a second approach, the drug-loaded NMOFs include encoded structural information or co-added agents to induce the structural distortion or stimulate the degradation of the NMOFs. Different chemical triggers such as pH changes, ions, ATP, or redox agents, and physical stimuli such as light or heat are applied to degrade the NMOFs, resulting in the release of the loads. In addition, enzymes, DNAzymes, and disease-specific biomarkers are used to unlock the gated NMOFs. The triggered release of drugs for cancer therapy, anti-blood clotting, and the design of autonomous insulin-delivery systems ("artificial pancreas") are discussed. Specifically, multi-drug carrier systems and functional NMOFs exhibiting dual and cooperative therapeutic functions are introduced. The future perspectives and applications of stimuli-responsive particles are addressed.


Asunto(s)
Investigación Biomédica , Sistemas de Liberación de Medicamentos , Estructuras Metalorgánicas/química , Nanopartículas/química , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Estructuras Metalorgánicas/síntesis química , Estructuras Metalorgánicas/metabolismo , Nanopartículas/metabolismo
14.
ACS Appl Mater Interfaces ; 13(8): 9520-9541, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33395247

RESUMEN

Sequence-specific nucleic acids recognizing low-molecular-weight ligands or macromolecules (aptamers) have found growing interest for biomedical applications. The present review article summarizes recent applications of aptamers as stimuli-responsive gating units of drug (or dye)-loaded nano- or microcarriers for controlled and targeted drug release. In the presence of cellular biomarkers, the nano-/microcarriers are unlocked by forming aptamer-ligand complexes. Different aptamer-functinalized nano-/microcarriers are presented, including inorganic nanomaterials, metal-organic framework nanoparticles, and soft materials. The chemistries associated with the preparation of the carriers and the mechanisms to unlock the carriers are discussed. Stimuli-responsive gated drug-loaded micro-/nanocarriers hold great promise as functional sense-and-treat materials for the targeted and selective release of drugs.


Asunto(s)
Aptámeros de Nucleótidos/química , Preparaciones de Acción Retardada/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , ADN/química , Liberación de Fármacos , Humanos , Ácidos Nucleicos Inmovilizados/química , Nanopartículas del Metal/química , Estructuras Metalorgánicas/química , Nanotubos de Carbono/química , Neoplasias/tratamiento farmacológico , Puntos Cuánticos/química
15.
Biochemistry ; 60(13): 956-965, 2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32613829

RESUMEN

The covalent linkage of catalytic units to aptamer sequence-specific nucleic acids exhibiting selective binding affinities for substrates leads to functional scaffolds mimicking native enzymes, nucleoapzymes. The binding of the substrates to the aptamer and their structural orientation with respect to the catalytic units duplicate the functions of the active center of enzymes. The possibility of linking the catalytic sites directly, or through spacer units, to the 5'-end, 3'-end, and middle positions of the aptamers allows the design of nucleoapzyme libraries, revealing structure-functions diversities, and these can be modeled by molecular dynamics simulations. Catalytic sites integrated into nucleoapzymes include DNAzymes, transition metal complexes, and organic ligands. Catalytic transformations driven by nucleoapzymes are exemplified by the oxidation of dopamine or l-arginine, hydroxylation of tyrosine to l-DOPA, hydrolysis of ATP, and cholic acid-modified esters. The covalent linkage of photosensitizers to the tyrosinamide aptamer leads to a photonucleoapzyme scaffold that binds the N-methyl-N'-(3-aminopropane)-4,4'-bipyridinium-functionalized tyrosinamide to the aptamer. By linking the photosensitizer directly, or through a spacer bridge to the 5'-end or 3'-end of the aptamer, we demonstrate a library of supramolecular photosensitizer/electron acceptor photonucleoapzymes mimicking the functions of photosystem I in the photosynthetic apparatus. The photonucleoapzymes catalyze the photoinduced generation of NADPH, in the presence of ferredoxin-NADP+-reductase (FNR), or the photoinduced H2 evolution catalyzed by Pt nanoparticles. The future prospects of nucleoapzymes and photonucleoapzymes are discussed.


Asunto(s)
Materiales Biomiméticos/química , ADN Catalítico/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Adenosina Trifosfato/metabolismo , Dominio Catalítico , ADN Catalítico/química , Fármacos Fotosensibilizantes/química , Proteínas del Complejo del Centro de Reacción Fotosintética/química
16.
J Environ Radioact ; 225: 106420, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32950750

RESUMEN

Sub-slab depressurisation systems have proven to effectively mitigate radon entry. A poor understanding of the fluid physics underlying the technique has been shown to lower the success rate substantially. This article describes a study of pressure fields in a sub-slab gravel bed induced by a soil depressurisation system consisting of perforated pipes run under the slab at a depth of 75 cm. The advantage of the approach is that pipes can be laid from outside the building to be protected. The study was conducted on a large-scale experimental facility where the variations in morphology and scope of pressure fields with different pipe combinations could be monitored and characterised. The findings showed that pressure was uniform across the entire area in the gravel bed, whereas the sensors buried in natural soil showed pressure to depend on distance from the source. Pressure transfer to the sub-slab plane was also observed to vary depending on the active pipe. Air-flow resistance studies in the layers of soil lying between the pipes and the gravel delivered different results for each pipe. That finding would appear to be related to the presence of preferential pathways in some parts of the soil. Total pressure when several pipes were activated was observed to be practically the same as the sum of the pressures transferred by each when working separately. The correlation between extraction fan power and pressure generated was also analysed. These and other factors are discussed and analysed from a perspective of the understanding of such highly effective techniques.


Asunto(s)
Monitoreo de Radiación , Radón/análisis , Contaminantes Radiactivos del Suelo/análisis , Suelo
17.
Chem Sci ; 11(21): 5592-5600, 2020 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-32874503

RESUMEN

The spatiotemporal stimulation of liposome-liposome or liposome-membrane fusion processes attracts growing interest as a means to mimic cell-cell interactions in nature and for using these processes for biomedical applications. We report the use of o-nitrobenzyl phosphate functionalized-cholesterol tethered nucleic acid-modified liposomes as functional photoresponsive units for inducing, by NIR-irradiation, spatiotemporal liposome-liposome or liposome-membrane fusion processes. The liposomes are loaded with upconversion nanoparticles (UCNPs) and their NIR irradiation (λ = 980 nm) yields luminescence at λ = 365 nm, providing a localized light-source to deprotect the o-nitrobenzyl phosphate groups and resulting in the fragmentation of the nucleic acid structures. In one system, the NIR-triggered fusion of two liposomes, L1 and L2, is exemplified. Liposome L1 is loaded with UCNPs and Tb3+ ions, and the liposome boundary is functionalized with a cholesterol-tethered, o-nitrobenzyl phosphate caged hairpin nucleic acid structure. Liposome L2 is loaded with 2,6-pyridinedicarboxylic acid, DPA, and its boundary is modified with a cholesterol-tethered nucleic acid, complementary to a part of the caged hairpin, associated with L1. NIR-irradiation of the L1/L2 mixture resulted in the photocleavage of the hairpin structure, associated with L1, and the resulting fragmented nucleic acid associated with L1 hybridized with the nucleic acid linked to L2, leading to the fusion of the two liposomes. The fusion process was followed by dynamic light scattering, and by monitoring the fluorescence of the Tb3+-DPA complex generated upon the fusion of the liposomes and their exchange of contents (fusion efficiency 30%). In a second system, the fusion of the liposomes L1, loaded with UCNPs and doxorubicin (DOX), with HeLa cancer cells functionalized with nucleic acid tethers, complementary to the hairpin units associated with the boundary of L1, and linked to the MUC-1 receptor sites associated with the HeLa cells, through a MUC-1 aptamer unit is exemplified. The effect of DOX-loaded L1/HeLa cell fusion on the cytotoxicity towards HeLa cells is addressed. The NIR UCNP-stimulated cleavage of the o-nitrobenzyl phosphate caged hairpin units associated with L1 leads to the fragmentation of the hairpin units and the resulting nucleic acid tethers hybridize with the nucleic acid-modified HeLa cells, resulting in the liposome-HeLa cell fusion and the release of DOX into the HeLa cells. Selective spatiotemporal cytotoxicity towards HeLa cells is demonstrated (ca. 40% cell killing within two days). The study presents a comprehensive stepwise set of experiments directed towards the development of NIR-driven liposome-liposome or liposome-membrane fusion processes.

18.
Animals (Basel) ; 10(7)2020 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-32660063

RESUMEN

Fin condition is a simple indicator of fish welfare, which anticipates detrimental effects on fish in aquaculture systems. This study evaluated the fin condition of Salmo salar at different abundances of the parasite Caligus rogercresseyi. Fish were exposed to infestation with copepodids and the cohort was allowed to develop to the adult stage. The relative fin index was measured. Significant differences between infested and control fish for both pectoral and anal fins were observed. Moreover, there were significant negative relationships between fin condition and parasite abundances for pectoral, anal, and pelvic fins, suggesting that infestations with C. rogercresseyi could be a possible cause for fin damage in Atlantic salmon. Moreover, this damage was associated with increased stress levels, suggesting that damage can be related to physiological changes on infested fish. According to these results, pectoral fin assessments have the potential to provide information on the welfare of fish with C. rogercresseyi infestation. Determining the causes of poor fin development may improve fish welfare, even when infested by parasites.

19.
Small ; 16(22): e2000880, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32374508

RESUMEN

Microcapsules consisting of hydrogel shells cross-linked by glucosamine-boronate ester complexes and duplex nucleic acids, loaded with dyes or drugs and functionalized with Au nanoparticles (Au NPs) or Au nanorods (Au NRs), are developed. Irradiation of Au NPs or Au NRs results in the thermoplasmonic heating of the microcapsules, and the dissociation of the nucleic acid cross-linkers. The separation of duplex nucleic acid cross-linkers leads to low-stiffness hydrogel shells, allowing the release of loads. Switching off the light-induced plasmonic heating results in the regeneration of stiff hydrogel shells protecting the microcapsules, leading to the blockage of release processes. The thermoplasmonic release of tetramethylrhodamine-dextran, Texas Red-dextran, doxorubicin-dextran (DOX-D), or camptothecin-carboxymethylcellulose (CPT-CMC) from the microcapsules is introduced. By loading the microcapsules with two different drugs (DOX-D and CPT-CMC), the light-controlled dose release is demonstrated. Cellular experiments show efficient permeation of Au NPs/DOX-D or Au NRs/DOX-D microcapsules into MDA-MB-231 cancer cells and inefficient uptake by MCF-10A epithelial breast cells. Cytotoxicity experiments reveal selective thermoplasmon-induced cytotoxicity of the microcapsules toward MDA-MB-231 cancer cells as compared to MCF-10A cells. Also, selective cytotoxicity towards MDA-MB-231 cancer cells upon irradiation of the Au NPs- and Au NRs-functionalized microcapsules at λ = 532 or 910 nm is demonstrated.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Nanotubos , Cápsulas , ADN , Doxorrubicina , Oro , Hidrogeles
20.
J Am Chem Soc ; 142(9): 4223-4234, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32031792

RESUMEN

A method to assemble stimuli-responsive nucleic acid-based hydrogel-stabilized microcapsule-in-microcapsule systems is introduced. An inner aqueous compartment stabilized by a stimuli-responsive hydrogel-layer (∼150 nm) provides the inner microcapsule (diameter ∼2.5 µm). The inner microcapsule is separated from an outer aqueous compartment stabilized by an outer stimuli-responsive hydrogel layer (thickness of ∼150 nm) that yields the microcapsule-in-microcapsule system. Different loads, e.g., tetramethyl rhodamine-dextran (TMR-D) and CdSe/ZnS quantum dots (QDs), are loaded in the inner and outer aqueous compartments. The hydrogel layers exist in a higher stiffness state that prevents inter-reservoir or leakage of the loads from the respective aqueous compartments. Subjecting the inner hydrogel layer to Zn2+-ions and/or the outer hydrogel layer to acidic pH or crown ether leads to the triggered separation of the bridging units associated with the respective hydrogel layers. This results in the hydrogel layers of lower stiffness allowing either the mixing of the loads occupying the two aqueous compartments, the guided release of the load from the outer aqueous compartment, or the release of the loads from the two aqueous compartments. In addition, a pH-responsive microcapsule-in-microcapsule system is loaded with glucose oxidase (GOx) in the inner aqueous compartment and insulin in the outer aqueous compartment. Glucose permeates across the two hydrogel layers resulting in the GOx catalyzed aerobic oxidation of glucose to gluconic acid. The acidification of the microcapsule-in-microcapsule system leads to the triggered unlocking of the outer, pH-responsive hydrogel layer and to the release of insulin. The pH-stimulated release of insulin is controlled by the concentration of glucose. While at normal glucose levels, the release of insulin is practically prohibited, the dose-controlled release of insulin in the entire diabetic range  is demonstrated. Also, switchable ON/OFF release of insulin is achieved highlighting an autonomous glucose-responsive microdevice operating as an "artificial pancreas" for the release of insulin.


Asunto(s)
Cápsulas/química , Portadores de Fármacos/química , Hidrogeles/química , Páncreas Artificial , Compuestos de Cadmio/química , Carbonato de Calcio/química , ADN Catalítico/química , Dextranos/química , Liberación de Fármacos , Colorantes Fluorescentes/química , Glucosa/química , Glucosa Oxidasa/química , Insulina/química , Puntos Cuánticos/química , Rodaminas/química , Compuestos de Selenio/química , Sulfuros/química , Compuestos de Zinc/química
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