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1.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38612828

RESUMO

Biomaterials play an important role in the development of advancing three dimensional (3D) in vitro skin models, providing valuable insights for drug testing and tissue-specific modeling. Commercial materials, such as collagen, fibrin or alginate, have been widely used in skin modeling. However, they do not adequately represent the molecular complexity of skin components. On this regard, the development of novel biomaterials that represent the complexity of tissues is becoming more important in the design of advanced models. In this study, we have obtained aged human decellularized dermal extracellular matrix (dECM) hydrogels extracted from cadaveric human skin and demonstrated their potential as scaffold for advanced skin models. These dECM hydrogels effectively reproduce the complex fibrillar structure of other common scaffolds, exhibiting similar mechanical properties, while preserving the molecular composition of the native dermis. It is worth noting that fibroblasts embedded within human dECM hydrogels exhibit a behavior more representative of natural skin compared to commercial collagen hydrogels, where uncontrolled cell proliferation leads to material shrinkage. The described human dECM hydrogel is able to be used as scaffold for dermal fibroblasts in a skin aging-on-a-chip model. These results demonstrate that dECM hydrogels preserve essential components of the native human dermis making them a suitable option for the development of 3D skin aging models that accurately represent the cellular microenvironment, improving existing in vitro skin models and allowing for more reliable results in dermatopathological studies.


Assuntos
Matriz Extracelular Descelularizada , Envelhecimento da Pele , Humanos , Idoso , Materiais Biocompatíveis/farmacologia , Hidrogéis , Colágeno
2.
Adv Sci (Weinh) ; : e2308561, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38590131

RESUMO

Underwater organisms exhibit sophisticated propulsion mechanisms, enabling them to navigate fluid environments with exceptional dexterity. Recently, substantial efforts have focused on integrating these movements into soft robots using smart shape-changing materials, particularly by using light for their propulsion and control. Nonetheless, challenges persist, including slow response times and the need of powerful light beams to actuate the robot. This last can result in unintended sample heating and potentially necessitate tracking specific actuation spots on the swimmer. To tackle these challenges, new azobenzene-containing photopolymerizable inks are introduced, which can be processed by extrusion printing into liquid crystalline elastomer (LCE) elements of precise shape and morphology. These LCEs exhibit rapid and significant photomechanical response underwater, driven by moderate-intensity ultraviolet (UV) and green light, being the actuation mechanism predominantly photochemical. Inspired by nature, a biomimetic four-lapped ephyra-like LCE swimmer is printed. The periodically illumination of the entire swimmer with moderate-intensity UV and green light, induces synchronous lappet bending toward the light source and swimmer propulsion away from the light. The platform eliminates the need of localized laser beams and tracking systems to monitor the swimmer's motion through the fluid, making it a versatile tool for creating light-fueled robotic LCE free-swimmers.

3.
Biomater Sci ; 12(6): 1549-1557, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38305143

RESUMO

DNA nanotechnology leverages Watson-Crick-Franklin base-pairing interactions to build complex DNA-based nanostructures (DNS). Due to DNA specific self-assembly properties, DNS can be designed with a total control of their architecture, which has been demonstrated to have an impact on the overall DNS features. Indeed, structural properties such as the shape, size and flexibility of DNS can influence their biostability as well as their ability to internalise into cells. We present here two series of simple DNS with small and precise variations related to their length or flexibility and study the influence that these structural changes have on their overall properties as drug nanocarriers. Results indicate that shorter and more flexible DNS present higher stability towards nuclease degradation. These structural changes also have a certain effect on their cell internalisation ability and drug release rate. Consequently, drug-loaded DNS cytotoxicity varies according to the design, with lower cell viability values obtained in the DNS exhibiting faster drug release and larger cell interaction rates. In summary, small changes in the structure of simple DNS can have an influence on their overall capabilities as drug nanocarriers. The effects reported here could guide the design of simple DNS for future therapeutic uses.


Assuntos
Nanoestruturas , Nanoestruturas/química , DNA/química , Nanotecnologia/métodos , Sobrevivência Celular
4.
Biomedicines ; 12(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38397949

RESUMO

BACKGROUND: The objective of this study was to evaluate the association of the presence of conjunctival ultraviolet autofluorescence (CUVAF) with the level and progression of myopia and the impact of reduced sunlight exposure during the COVID-19 pandemic confinement (PC). METHODS: A retrospective observational study was carried out using three cohorts, children (9-17 years old), young adults (18-25 years old), and adults (>40 years old) with myopia (≤0.75D) and at least three annual eye examinations (before and after PC). All participants underwent an automatic objective refraction and CUVAF area analysis. All the participants filled out a questionnaire regarding lifestyle and myopia history. RESULTS: The 298 recruited participants showed that during the PC, children's and young adults' myopia progression rate increased on average by -0.50 and -0.30 D/year, respectively, compared with the pre-pandemic level (p < 0.0001 and p < 0.01). A significantly greater progression was observed in those with low baseline myopia compared to those with moderate or high myopia (p < 0.01). CUVAF shows its protective effect associated with outdoor activity (OA) with regard to the age of onset of myopia and mean diopters (p < 0.01). In fact, although there were no differences in the increase in diopters between children with and without CUVAF during the PC, those who had CUVAF started with lower gains (-0.3 D/year) compared to those who did not (-0.5 D/year; p < 0.05). The myopia treatments (atropine drops, Ortho-K, and MiSight® contact lenses) showed a reduction effect in myopic progression rate post-PC in comparison with non-treated children (p < 0.0001, p < 0.0001 and p < 0.01, respectively). CONCLUSIONS: The strict restriction of OA during PC led to the rate of myopia progression doubling among children and young adults. This progression occurred mainly in children with previously low myopia, and CUVAF, as a biomarker of OA, reflects its potential to provide benefits in the form of recommended behavioral changes to protect against the development of myopia.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38284792

RESUMO

BACKGROUND: Swallowed topical corticosteroids (tC) are common therapy for patients with eosinophilic esophagitis (EoE). Widely heterogeneous results have occurred due to their active ingredients, formulations and doses. OBJECTIVE: To assess the effectiveness of topical corticosteroid therapy for EoE in real-world practice. METHODS: Cross-sectional study analysis of the multicentre EoE CONNECT registry. Clinical remission was defined as a decrease of ≥50% in dysphagia symptom scores; histological remission was defined as a peak eosinophil count below 15 per high-power field. The effectiveness in achieving clinico-histological remission (CHR) was compared for the main tC formulations. RESULTS: Overall, data on 1456 prescriptions of tC in monotherapy used in 866 individual patients were assessed. Of those, 904 prescriptions with data on formulation were employed for the induction of remission; 234 reduced a previously effective dose for maintenance. Fluticasone propionate formulations dominated the first-line treatment, while budesonide was more common in later therapies. A swallowed nasal drop suspension was the most common formulation of fluticasone propionate. Doses ≥0.8 mg/day provided a 65% CHR rate and were superior to lower doses. Oral viscous solution prepared by a pharmacist was the most common prescription of budesonide; 4 mg/day provided no benefit over 2 mg/day (CHR rated being 72% and 80%, respectively). A multivariate analysis revealed budesonide orodispersible tablets as the most effective therapy (OR 18.9, p < 0.001); use of higher doses (OR 4.3, p = 0.03) and lower symptom scores (OR 0.9, p = 0.01) were also determinants of effectiveness. CONCLUSION: Reduced symptom severity, use of high doses, and use of budesonide orodispersible tablets particularly were all independent predictors of tC effectiveness.

6.
United European Gastroenterol J ; 12(1): 122-138, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38050339

RESUMO

BACKGROUND: Management of Helicobacter pylori (H. pylori) infection requires co-treatment with proton pump inhibitors (PPIs) and the use of antibiotics to achieve successful eradication. AIM: To evaluate the role of dosage of PPIs and the duration of therapy in the effectiveness of H. pylori eradication treatments based on the 'European Registry on Helicobacter pylori management' (Hp-EuReg). METHODS: Hp-EuReg is a multicentre, prospective, non-interventionist, international registry on the routine clinical practice of H. pylori management by European gastroenterologists. All infected adult patients were systematically registered from 2013 to 2022. RESULTS: Overall, 36,579 patients from five countries with more than 1000 patients were analysed. Optimal (≥90%) first-line-modified intention-to-treat effectiveness was achieved with the following treatments: (1) 14-day therapies with clarithromycin-amoxicillin-bismuth and metronidazole-tetracycline-bismuth, both independently of the PPI dose prescribed; (2) All 10-day (except 10-day standard triple therapy) and 14-day therapies with high-dose PPIs; and (3) 10-day quadruple therapies with clarithromycin-amoxicillin-bismuth, metronidazole-tetracycline-bismuth, and clarithromycin-amoxicillin-metronidazole (sequential), all with standard-dose PPIs. In first-line treatment, optimal effectiveness was obtained with high-dose PPIs in all 14-day treatments, in 10- and 14-day bismuth quadruple therapies and in 10-day sequential with standard-dose PPIs. Optimal second-line effectiveness was achieved with (1) metronidazole-tetracycline-bismuth quadruple therapy for 14- and 10 days with standard and high-dose PPIs, respectively; and (2) levofloxacin-amoxicillin triple therapy for 14 days with high-dose PPIs. None of the 7-day therapies in both treatment lines achieved optimal effectiveness. CONCLUSIONS: We recommend, in first-line treatment, the use of high-dose PPIs in 14-day triple therapy and in 10-or 14-day quadruple concomitant therapy in first-line treatment, while standard-dose PPIs would be sufficient in 10-day bismuth quadruple therapies. On the other hand, in second-line treatment, high-dose PPIs would be more beneficial in 14-day triple therapy with levofloxacin and amoxicillin or in 10-day bismuth quadruple therapy either as a three-in-one single capsule or in the traditional scheme.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Adulto , Humanos , Inibidores da Bomba de Prótons/uso terapêutico , Metronidazol , Claritromicina/uso terapêutico , Levofloxacino/uso terapêutico , Bismuto , Estudos Prospectivos , Quimioterapia Combinada , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Amoxicilina/uso terapêutico , Tetraciclina , Sistema de Registros
7.
Nanoscale ; 16(3): 1238-1246, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38116590

RESUMO

The desire to continually reduce the lower limits of semiconductor integrated circuit (IC) fabrication methods continues to inspire interest in unimolecular electronics as a platform technology for the realization of future (opto)electronic devices. However, despite successes in developing methods for the construction and measurement of single-molecule and large-area molecular junctions, exercising control over the precise junction geometry remains a significant challenge. Here, host-guest complexes of the wire-like viologen derivative 1,1'-bis(4-(methylthio)-phenyl)-[4,4'-bipyridine]-1,1'-diium chloride ([1][Cl]2) and cucurbit[7]uril (CB[7]) have been self-assembled in a regular pattern over a gold substrate. Subsequently, ligandless gold nanoparticles (AuNPs) synthesized in situ are deposited over the host-guest array. The agreement between the conductance of individual mono-molecular junctions, appropriately chosen as a function of the AuNP diameter, within this array determined by conductive probe atomic force microscope (c-AFM) and true single-molecule measurements for a closely similar host-guest complex within a scanning tunneling microscope break-junction (STM-BJ) indicates the formation of molecular junctions derived from these host-guest complexes without deleterious intermolecular coupling effects.

8.
J Mater Chem A Mater ; 11(43): 23211-23222, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38013915

RESUMO

Proton exchange membrane fuel cells require reduced construction costs to improve commercial viability, which can be fueled by elimination of platinum as the O2 reduction electrocatalyst. The past 10 years has seen significant developments in synthesis, characterisation, and electrocatalytic performance of the most promising alternative electrocatalyst; single metal atoms coordinated to nitrogen-doped carbon (M-N-C). In this Perspective we recap some of the important achievements of M-N-Cs in the last decade, as well as discussing current knowledge gaps and future research directions for the community. We provide a new outlook on M-N-C stability and atomistic understanding with a set of original density functional theory simulations.

9.
Sci Rep ; 13(1): 17585, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845333

RESUMO

Blepharoptosis is a recognized cause of reversible vision loss and a non-specific indicator of neurological issues, occasionally heralding life-threatening conditions. Currently, diagnosis relies on human expertise and eyelid examination, with most existing Artificial Intelligence algorithms focusing on eyelid positioning under specialized settings. This study introduces a deep learning model with convolutional neural networks to detect blepharoptosis in more realistic conditions. Our model was trained and tested using high quality periocular images from patients with blepharoptosis as well as those with other eyelid conditions. The model achieved an area under the receiver operating characteristic curve of 0.918. For validation, we compared the model's performance against nine medical experts-oculoplastic surgeons, general ophthalmologists, and general practitioners-with varied expertise. When tested on a new dataset with varied image quality, the model's performance remained statistically comparable to that of human graders. Our findings underscore the potential to enhance telemedicine services for blepharoptosis detection.


Assuntos
Inteligência Artificial , Blefaroptose , Humanos , Blefaroptose/diagnóstico , Redes Neurais de Computação , Algoritmos , Curva ROC
10.
Sci Rep ; 13(1): 16310, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770602

RESUMO

To evaluate the age-related efficacy and safety of atropine 0.01% eye drops over 2 years for myopia control in a multicentric pediatric Spanish cohort. A non-controlled, interventional, prospective multicenter study was conducted as an extension of the Spanish Group of Atropine Treatment for Myopia Control Study (GTAM 1). Children aged 6-14 years with myopia from - 2.00 to - 6.00 D, astigmatism < 1.50 D and documented annual myopic progression of at least - 0.50 D under cycloplegic examination were recruited. From the original cohort of 105 participants, 92 children who had been receiving atropine 0.01% eye drops once nightly in each eye for 1 year continued their participation in this extended study (GTAM 2). All the patients underwent a standardized quarterly follow-up protocol, which included measurements of best-corrected visual acuity (BCVA), cycloplegic autorefraction, axial length (AL), anterior chamber depth (ACD), and pupil diameter. The study sample was divided into three age groups: 6-8, 9-11, and 12-14 years old. The mean change in cycloplegic spherical equivalent (SE) and axial length (AL) during the 24 months of follow-up was analyzed. Correlations between SE and AL, as well as the distribution of annual progression, were evaluated. Adverse effects were recorded using a specific questionnaire. Finally, 81 children completed the follow-up and were included in the analysis. Over the 2-year period, the mean changes in SE and AL were - 0.88 ± 0.60 D and 0.49 ± 0.25 mm, respectively. Additionally, 51 patients (63%) experienced SE annual progression lower than - 0.50 D. The correlation between the progression of SE and AL during the total period of treatment was mild (r = - 0.36; p < 0.001). There were no differences between the first and the second year of treatment in the progression of SE (- 0.42 ± 0.41 D versus - 0.45 ± 0.39 D; p = 0.69) or AL (0.25 ± 0.16 mm versus 0.23 ± 0.14 mm; p = 0.43). Older patients (12-14 years old) showed less AL progression than younger children (6-8 years old): 0.36 ± 0.18 mm versus 0.59 ± 0.30 mm; p = 0.01. Adverse effects were mild, infrequent, and decreased over time. On average, the myopia progression in control groups from other published biannual studies exceeded that observed in our study. Over 2 years, atropine 0.01% demonstrated a safe treatment for controlling myopia progression in a multicentric cohort of Spanish children. The effect remained stable during this period. Older patients exhibited a more favorable response in terms of AL enlargement. However, further studies are needed to investigate the age-related effect of low-dose atropine in the Caucasian population.


Assuntos
Atropina , Miopia , Humanos , Criança , Adolescente , Atropina/efeitos adversos , Midriáticos/efeitos adversos , Estudos Prospectivos , Administração Tópica , Miopia/tratamento farmacológico , Refração Ocular , Soluções Oftálmicas/uso terapêutico , Progressão da Doença
11.
Chemistry ; 29(62): e202302377, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37605638

RESUMO

Carbon nitride materials (CN) have become one of the most studied photocatalysts within the last 15 years. While CN absorbs visible light, its low porosity and fast electron-hole recombination hinder its photoelectric performance and have motivated the research in the modification of its physical and chemical properties (such as energy band structure, porosity, or chemical composition) by different means. In this Concept we review the utilization of supramolecular crystals as CN precursors to tailor its properties. We elaborate on the features needed in a supramolecular crystal to serve as CN precursor, we delve on the influence of metal-free crystals in the morphology and porosity of the resulting materials and then discuss the formation of single atoms and heterojunctions when employing a metal-organic crystal. We finally discuss the performance of CN photoanodes derived from crystals and highlight the current standing challenges in the field.

12.
Front Bioeng Biotechnol ; 11: 1191327, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545884

RESUMO

The new and unique possibilities that nanomaterials offer have greatly impacted biomedicine, from the treatment and diagnosis of diseases, to the specific and optimized delivery of therapeutic agents. Technological advances in the synthesis, characterization, standardization, and therapeutic performance of nanoparticles have enabled the approval of several nanomedicines and novel applications. Discoveries continue to rise exponentially in all disease areas, from cancer to neurodegenerative diseases. In Spain, there is a substantial net of researchers involved in the development of nanodiagnostics and nanomedicines. In this review, we summarize the state of the art of nanotechnology, focusing on nanoparticles, for the treatment of diseases in Spain (2017-2022), and give a perspective on the future trends and direction that nanomedicine research is taking.

13.
J Clin Med ; 12(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445399

RESUMO

BACKGROUND AND AIMS: Several methods are available to diagnose Helicobacter pylori infection. Our objective was to evaluate the tests used for both the initial diagnosis and the confirmation of eradication after treatment in Europe. METHODS: The European Registry on the management of Helicobacter pylori infection is an international, multicentre, prospective, non-interventional registry aiming to evaluate the management of Helicobacter pylori-infected patients in Europe. Countries with at least 100 cases registered from June 2013 to April 2021, and with a validated diagnostic method were analysed. Data were quality reviewed. RESULTS: A total of 34,920 adult patients from 20 countries were included (mean age 51 years; 61% women). To establish the initial diagnosis, invasive tests were performed in 19,801 (71%) patients, non-invasive in 11,369 (41%), and both in 3437 (12%). The most frequent were histology (n = 11,885; 43%), a rapid urease test (n = 10,636; 38%) and an urea breath test (n = 7577; 27%). According to the age, invasive tests were indicated in 11,179 (77%) ≥50 years, and in 8603 (65%) <50 years. Depending on the country, the use of invasive tests ranged from 29-99% in <50 years to 60-99% in ≥50. Most of the tests used to confirm eradication were non-invasive (n = 32,540; 93%), with the urea breath test being the most frequent (n = 32,540; 78%). In 2983 (9%) post-treatment tests, histology (n = 1887; 5%) or a rapid urease test (n = 1223; 4%) were performed. CONCLUSION: A great heterogeneity was observed for the initial diagnosis and confirmation of the eradication. The reasons for the apparent lack of adherence to the clinical guidelines should be further explored.

14.
Gut ; 72(11): 2031-2038, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37468228

RESUMO

BACKGROUND: The recommended schedule for single capsule bismuth quadruple therapy (scBQT, Pylera) includes a proton pump inhibitor (PPI) two times a day and three scBQT capsules four times a day. Four times a day treatments are inconvenient and reduce adherence. In contrast, adherence improves with three times a day schedules. In clinical practice, many gastroenterologists use four capsule scBQT three times a day. However, the effectiveness and safety of this latter approach remain uncertain. AIM: To assess the effectiveness and safety of scBQT administered three times a day in the patients included in the European Registry on Helicobacter pylori Management (Hp-EuReg). METHODS: All Spanish adult patients registered in the Asociación Española de Gastroenterología Research Electronic Data Capture (REDCap) database from June 2013 to March 2021 receiving 10-day scBQT were analysed. Modified intention-to-treat effectiveness, adherence and the safety of scBQT given three times a day were calculated and compared with the four times a day schedule. A multivariate analysis was performed to determine independent factors predicting cure of the infection. RESULTS: Of the 3712 cases, 2516 (68%) were four times a day and 1196 (32%) three times a day. Mean age was 51 years, 63% were women and 15% had a peptic ulcer. The three times a day schedule showed significantly better overall cure rates than four times a day (1047/1112, 94%; 95% CI 92.7 to 95.6 vs 2207/2423, 91%; 95% CI 89.9 to 92.2, respectively, p=0.002). Adherence and safety data were similar for both regimens. In the multivariate analysis, three times a day dosage, first-line therapy, use of standard or high-dose PPIs and adherence over 90% were significantly associated with cure of the infection. CONCLUSIONS: ScBQT prescribed three times a day was more effective than the traditional four times a day schedule. No differences were observed in treatment adherence or safety.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Bismuto/efeitos adversos , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Quimioterapia Combinada , Metronidazol/uso terapêutico , Inibidores da Bomba de Prótons , Sistema de Registros , Amoxicilina/uso terapêutico
15.
Macromol Biosci ; 23(10): e2300108, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37269065

RESUMO

Mechanical interactions between cells and their microenvironment play an important role in determining cell fate, which is particularly relevant in metastasis, a process where cells invade tissue matrices with different mechanical properties. In vitro, type I collagen hydrogels have been commonly used for modeling the microenvironment due to its ubiquity in the human body. In this work, the combined influence of the stiffness of these hydrogels and their ultrastructure on the migration patterns of HCT-116 and HT-29 spheroids are analyzed. For this, six different types of pure type I collagen hydrogels by changing the collagen concentration and the gelation temperature are prepared. The stiffness of each sample is measured and its ultrastructure is characterized. Cell migration studies are then performed by seeding the spheroids in three different spatial conditions. It is shown that changes in the aforementioned parameters lead to differences in the mechanical stiffness of the matrices as well as the ultrastructure. These differences, in turn, lead to distinct cell migration patterns of HCT-116 and HT-29 spheroids in either of the spatial conditions tested. Based on these results, it is concluded that the stiffness and the ultrastructural organization of the matrix can actively modulate cell migration behavior in colorectal cancer spheroids.

18.
Nat Rev Chem ; 7(3): 184-201, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37117902

RESUMO

The Mo/Fe nitrogenase enzyme is unique in its ability to efficiently reduce dinitrogen to ammonia at atmospheric pressures and room temperature. Should an artificial electrolytic device achieve the same feat, it would revolutionize fertilizer production and even provide an energy-dense, truly carbon-free fuel. This Review provides a coherent comparison of recent progress made in dinitrogen fixation on solid electrodes, homogeneous catalysts and nitrogenases. Specific emphasis is placed on systems for which there is unequivocal evidence that dinitrogen reduction has taken place. By establishing the cross-cutting themes and synergies between these systems, we identify viable avenues for future research.

19.
Adv Mater ; 35(14): e2211022, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36739474

RESUMO

Atomic Fe in N-doped carbon (FeNC) electrocatalysts for oxygen (O2 ) reduction at the cathode of proton exchange membrane fuel cells are the most promising alternative to platinum-group-metal catalysts. Despite recent progress on atomic FeNC O2  reduction, their controlled synthesis and stability for practical applications remain challenging. A two-step synthesis approach has recently led to significant advances in terms of Fe-loading and mass activity; however, the Fe utilization remains low owing to the difficulty of building scaffolds with sufficient porosity that electrochemically exposes the active sites. Herein, this issue is addressed by coordinating Fe in a highly porous nitrogen-doped carbon support (≈3295 m2  g-1 ), prepared by pyrolysis of inexpensive 2,4,6-triaminopyrimidine and a Mg2+ salt active site template and porogen. Upon Fe coordination, a high electrochemical active site density of 2.54 × 1019  sites gFeNC -1  and a record 52% FeNx electrochemical utilization based on in situ nitrite stripping are achieved. The Fe single atoms are characterized pre- and post-electrochemical accelerated stress testing by aberration-corrected high-angle annular dark field scanning transmission electron microscopy, showing no Fe clustering. Moreover, ex situ X-ray absorption spectroscopy and low-temperature Mössbauer spectroscopy suggest the presence of penta-coordinated Fe sites, which are further studied by density functional theory calculations.

20.
Gastroenterol. hepatol. (Ed. impr.) ; 46(2): 102-108, Feb. 2023. mapas, tab, ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-226573

RESUMO

Introducción: La incidencia de la enfermedad inflamatoria intestinal (EII) está aumentando en todo el mundo. Objetivos: Evaluar la incidencia de EII en la comunidad autónoma de Castilla y León y describir las características clínicas de los pacientes al diagnóstico, el tipo de tratamiento recibido y la evolución clínica durante el primer año. Material y métodos: Estudio prospectivo, multicéntrico y poblacional en el que se incluyeron pacientes adultos diagnosticados de EII (enfermedad de Crohn [EC], colitis ulcerosa [CU] o colitis indeterminada [CI]) durante el año 2017 procedentes de 8 centros de Castilla y León. Se incluyeron variables epidemiológicas, clínicas y terapéuticas. Se calculó la incidencia global y por enfermedades. Resultados: Doscientos noventa pacientes fueron diagnosticados de EII (54,5% de CU, 45.2% de EC y 0,3% de CI), con una mediana de seguimiento de 9 meses (rango 8-11). La tasa de incidencia fue de 16,6 casos/100.000 habitantes-año (9/105 casos de CU y 7,5/105 casos de EC), con una proporción CU/EC de 1,2:1. Los pacientes con EC recibieron significativamente más corticoides sistémicos (47% vs. 30%; p=0,002), más tratamiento inmunomodulador (81% vs. 19%; p=0,000), más tratamiento biológico (29% vs. 8%; p=0,000) y mayor necesidad de cirugía (11% vs. 2%; p=0,000). Conclusiones: La incidencia de pacientes con CU en nuestro medio se incrementa, mientras que la de EC se mantiene estable, con una historia natural de la enfermedad peor (uso de corticoides, inmunosupresores, biológicos y cirugía) para los pacientes con EC comparado con los pacientes con CU en el primer año de seguimiento.(AU)


Introduction: The incidence of inflammatory bowel disease (IBD) is increasing worldwide. Objectives: To evaluate the incidence of IBD in Castilla y León describing clinical characteristics of the patients at diagnosis, the type of treatment received and their clinical course during the first year. Materials and methods: Prospective, multicenter and population-based incidence cohort study. Patients aged >18 years diagnosed during 2017 with IBD (Crohn's disease [CD], ulcerative colitis [UC] and indeterminate colitis [IC]) were included from 8 hospitals in Castilla y León. Epidemiological, clinical, and therapeutic variables were registered. The global incidence and disease incidence were calculated.Results290 patients were diagnosed with IBD (54.5% UC, 45.2% CD, and 0.3% IC), with a median follow-up of 9 months (range 8−11). The incidence rate of IBD in Castilla y Leon in 2017 was 16.6 cases per 10,000 inhabitants-year (9/105 UC cases and 7.5/105 CD cases), with a UC/CD ratio of 1.2:1. Use of systemic corticosteroids (47% vs 30%; P=.002), immunomodulatory therapy (81% vs 19%; P=.000), biological therapy (29% vs 8%; P=.000), and surgery (11% vs 2%; p=.000) were significatively higher among patients with CD comparing with those with UC. Conclusions: The incidence of patients with UC in our population increases while the incidence of patients with CD remains stable. Patients with CD present a worse natural history of the disease (use of corticosteroids, immunomodulatory therapy, biological therapy and surgery) compared to patients with UC in the first year of follow-up.(AU)


Assuntos
Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/história , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doença de Crohn , Incidência , Colite Ulcerativa , Gastroenterologia , Gastroenteropatias , Estudos Prospectivos , Estudos Populacionais em Saúde Pública
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